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Life Sciences, Molecular Biology; CRISPR system; yeast; gene edition
Online: 2 December 2018 (10:13:38 CET)
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This review summarizes the use of CRISPR system in yeasts, identifying advantages and disadvantages of its applications. 39 articles were evaluated including 12 articles that discussed the advantages of new CRISPR systems that improved the initial system, and another 27 were evaluated, among these: three were applications in Cryptococcus neoformans, four in candida sp., three in Schizosaccharomyces pombe, nine in Saccharomyces cerevisiae, four in Yarrowia lipolytica, and four in industrially important yeasts such as Pichia pastoris and Saccharomyces pastorianus. It was concluded that the CRISPR system is one of the most versatile genetic editing systems available nowadays. It can be applied in different organisms for several effects including gene knock-outs, performing point mutations, gene expression, or even applying multiple edition operations in several genes. However, we recognize that numerous studies lack a control group of the mutated strains, which leaves many questions unanswered. For instance, the extent and precision of this techniques, it also represents a risk to biosecurity standards. Therefore, this review shows the compilation of CRISPR system information, which could be used to generate different alternatives in the industry and clinical fields.
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Life Sciences, Molecular Biology; DISC1, neurodevelopment, synapse, CRMP-2, MUNC18, syntaxin, NECAP1, proteomics
Online: 19 November 2018 (12:25:42 CET)
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A balanced chromosomal translocation disrupting DISC1 (Disrupted in Schizophrenia 1) gene has been linked to psychiatric diseases, such as major depression, bipolar disorder and schizophrenia. Since the discovery of this translocation, many studies have focused on understating the role of the truncated isoform of DISC1, hypothesizing that the gain of function of this protein could be behind the neurobiology of mental conditions, but not so many studies have focused in the mechanisms impaired due to its loss of function. For that reason, we perform an analysis on the cellular proteome of primary neurons in which DISC1 was knocked down with the goal of identifying relevant pathways directly affected by DISC1 loss of function. Using an unbiased proteomic approach, we found that the expression of 31 proteins related to neurodevelopment (e.g. CRMP-2, stathmin) and synaptic function (e.g. MUNC-18, NCS-1) is regulated by DISC1 in primary mouse neurons. Hence, this study reinforces the idea that DISC1 is a unifying regulator of both neurodevelopment and synaptic function, thereby providing a link between these two key anatomical and cellular circuitries.
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Life Sciences, Molecular Biology; cystic fibrosis; gene therapy; gene targeting; gene integration
Online: 19 November 2018 (10:14:02 CET)
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Cystic Fibrosis (CF) is an inherited monogenic disorder, amenable to gene based therapies. Because CF lung disease is currently the major cause of mortality and morbidity, and lung airway is readily accessible to gene delivery, the major CF gene therapy effort at present is directed to the lung. Although airway epithelial cells are renewed slowly, permanent gene correction through gene editing or targeting in airway stem cells is needed to perpetuate the therapeutic effect. Transcription activator-like effector nuclease (TALEN) has been utilized widely for a variety of gene editing applications. The stringent requirement for nuclease binding target sites allows for gene editing with precision. In this study, we engineered helper-dependent adenoviral (HD-Ad) vectors to deliver a pair of TALENs together with donor DNA targeting the human AAVS1 locus. With homology arms of 4 kb in length, we demonstrated precise insertion of either a LacZ reporter gene or a human CFTR minigene into the target site. Using the LacZ reporter, we determined the efficiency of gene integration to be about 5%. In the CFTR vector transduced cells, we have detected both CFTR mRNA and protein expression by qPCR and Wetern analysis, respectively. We have also confirmed CFTR function correction by flurometric Image Plate Reader (FLIPR) and iodide efflux assays. Taking together, these findings suggest a new direction for future in vitro and in vivo studies in CF gene editing.
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Life Sciences, Molecular Biology; RNA modification; tRNA methyltransferase; tRNA modification; methylase
Online: 16 November 2018 (07:31:19 CET)
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More than 90 different modified nucleosides have been identified in tRNA. Among the tRNA modifications, the 7-methylguanosine (m7G) modification is found widely in eubacteria, eukaryotes, and a few archaea. In most cases, the m7G modification occurs at position 46 in the variable region and is a product of tRNA (m7G46) methyltransferase. The m7G46 modification forms a tertiary base pair with C13-G22, and stabilizes the tRNA structure. Recently, we have proposed a reaction mechanism for eubacterial tRNA m7G methyltransferase (TrmB) based on the results of biochemical studies and previous biochemical, bioinformatic, and structural studies by others. However, an experimentally determined mechanism of methyl-transfer remains to be ascertained. The physiological functions of m7G46 in tRNA have started to be determined over the past decade. To be able to better respond to diseases and infections in which the m7G modification is considered to be involved, it is still necessary to further understand the catalytic mechanism of AdoMet and/or the tRNA bound form of m7G methyltransferases. In this review, information of tRNA m7G modifications and tRNA m7G methyltransferases are summarized and the differences in reaction mechanism between tRNA m7G methyltransferase and rRNA or mRNA m7G methylation enzyme are discussed.
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Life Sciences, Molecular Biology; sequencing technologies; NGS; genome research; genome assembly; variant calling; RNA-Seq; transcriptome assembly; bioinformatics; molecular biology; education
Online: 13 November 2018 (10:22:06 CET)
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Combined awareness about the power and limitations of bioinformatics and molecular biology enables advanced research based on high-throughput data. Despite an increasing demand for scientists with a combined background in both fields, the education in dry lab and wet lab is often separated. This work describes an example of integrated education with focus on genomics and transcriptomics. Participants learn computational and molecular biology methods in the same practical course. Peer-review is applied as a teaching method to foster cooperative learning of students with heterogeneous backgrounds. Evaluation results indicate acceptance and appreciation of this approach.
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Life Sciences, Molecular Biology; astrocytes; glutamine; SN1 (SNAT3); Sp1; protein kinase C; ammonia; transport
Online: 12 November 2018 (10:02:12 CET)
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The involvement of astrocytic SN1 (SNAT3) transporter in ammonia-induced L-glutamine retention was recently documented in mouse cultured astrocytes. Here we investigated the involvement of specificity protein 1 (Sp1) transcription factor in SN1 regulation in ammonium chloride (“ammonia”)-treated astrocytes. Sp1 expression and its cellular localization were determined using real-time qPCR, Western blot and confocal microscopy, respectively. Sp1 binding to Snat3 promoter was analyzed by chromatin immunoprecipitation. Ammonia-induced Sp1 regulatory role in SN1-mediated [3H]glutamine transport was verified using siRNA and mithramycin A. The involvement of protein kinase C (PKC) isoforms in Sp1 level/phosphorylation status was verified using siRNA technology. Sp1 translocation to the nuclei and its enhanced binding to Snat3 promoter, along with Sp1 dependence of system N-mediated [3H]glutamine transport were observed in astrocytes upon ammonia exposure. Ammonia decreased the level of phosphorylated Sp1, and the effect was reinforced by long-term incubation with PKC modulator, phorbol 12-myristate 13-acetate, a treatment likely to dephosphorylate Sp1. Furthermore, silencing of PKCδ isoform abolished the increase of Sp1 level by ammonia. Collectively, the results demonstrate the regulatory role of Sp1 in regulation of SN1 expression and activity in ammonia-treated astrocytes and implicate altered Sp1 phosphorylation status in this capacity.
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Life Sciences, Molecular Biology; hypobaric hypoxia; myocardium; interstitial space; fibroblasts; fibrosis; succinic acid; rats
Online: 12 November 2018 (05:16:27 CET)
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The myocardial extracellular matrix is not a passive entity, but rather a complex and dynamic microenvironment which represents an important structural and signaling system within the myocardium. Understanding the fundamental role of hypoxia and peroxidation in the genesis of many cardiovascular diseases has stimulated the development of strategies that can enhance the energy-producing functions of cells. Revealing the alterations in cardiac metabolism and function associated with sustained exposure to high altitude advances our understanding of hypoxia-related disease. The study was conducted on 26 adult males of Wistar rats weighing 220–310 g, divided into 3 groups. The first control group consisted of 6 intact animals, the second group included 10 rats which were exposed to hypobaric hypoxia without medication for 30 days. Third group was composed of 10 rats, which were medicated by succinic acid solution which was injected intraperitoneally once a day at the rate of 0.5 mL/100 g of animal body weight 15 minutes before hypoxic exposure for 30 days. Fibrosis in the myocardium inevitably leads to increased myocardial stiffness, resulting in systolic and diastolic dysfunction, neurohormonal activation and, ultimately, heart failure Changes in cardiac highenergy phosphate metabolism may underlie the myocardial dysfunction caused by hypobaric hypoxia. Reduced oxygen delivery by microvascular damage, increased perivascular fibrosis associated with reduced cellular oxygen availability may contribute to contractile failure. Succinic acid combined with inosine acts as a high-energy phosphate reserve, to maintain adenosine triphosphate at levels sufficient to support contractile function.
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Life Sciences, Molecular Biology; Inonotus Obliquus, Melanogenesis, B16F10, Tyrosinase, MITF
Online: 9 November 2018 (13:36:36 CET)
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Melanogenesis is a biosynthetic pathway for producing of the pigment melanin in human skin. Tyrosinase, a key enzyme, catalyzing is the first step in melanogenesis and the downregulation of the tyrosinase enzyme activity is the most reported method for anti-melanogenesis. According to the hyperpigmentation as an important issue in cosmetic industry, there is a big demand for melanogenesis inhibitors. In the present study, we identified the anti-melanogenic effect of Inonotus Obliquus in α-MSH-induced B16F10 mouse melanoma cells as a new inhibitor. Comparing with control and Inonotus Obliquus extracts treated B16F10, we identified melanin contents, tyrosinase activity, tyrosinase mRNA and protein expression, MITF activity using a constructed plasmid. As shown in these results, we demonstrated that Inonotus Obliquus extracts down-regulated melanin synthesis using down-regulating activity and expression of tyrosinase which is key enzyme to produce melanin. In addition, we revealed expression of tyrosinase is regulated by MITF through repressing MITF transcriptional activity. Inonotus Obliquus extracts has potential to repress melanogenesis and decreased of hyperpigmentation and to use as cosmetic ingredient.
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Life Sciences, Molecular Biology; quercetogetin (QUE); anti-inflammatory; inducible nitric oxide synthase (iNOS); cyclooxygenase-2 (COX-2); MAPK; NF-κB
Online: 9 November 2018 (03:31:28 CET)
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Citrus peel has been used in Asian traditional medicine for the treatment of cough, asthma, and bronchial disorders. However, the anti-inflammatory effect of quercetogetin (QUE), a polymethoxylated flavone isolated from the peel of citrus unshui is poorly understood. We investigated the anti-inflammatory effect and the molecular mechanisms of QUE in lipopolysaccharide (LPS)-induced RAW264.7 cells. QUE inhibited the production of NO and prostaglandin E2 by suppressing the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at both the mRNA and protein levels. QUE suppressed the production of proinflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. QUE also inhibited the translocation of the nuclear factor kappa B subunit, p65, into the nucleus by interrupting the phosphorylation of IκB-α in LPS-induced RAW 264.7 cells. Based on the finding that QUE significantly decreased p-ERK protein expression in LPS-induced RAW264.7 cells, we confirmed that suppression of the inflammatory process by QUE was mediated through the MAPK pathway. This is the first report on the strong anti-inflammatory effects of QUE, which is a compound that can potentially be used as a therapeutic agent for inflammatory diseases.
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Life Sciences, Molecular Biology; B cells, RNA splicing, ER stress, unfolded protein response, RIDD
Online: 8 November 2018 (14:19:16 CET)
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Endo-reticular stress induces the unfolded protein response including a highly conserved set of genes crucial for cell survival against a variety of onslaughts. Among the activated stress response genes is Ire1, which undergoes auto-phosphorylation and acquires a regulated Ire1-dependent mRNA decay activity. Ire1P non-canonically splices the mRNA for Xbp1 in the cytoplasm. This spliced Xbp1 serves as mRNA encoding a transcription factor for unfolded protein response genes. Meanwhile the mRNA decay function of Ire1P degrades other cellular mRNAs and can cause changes to the translation machinery by altering regulators in a cell specific manner. Naïve splenic B cells differentiate into Antibody Secreting Cells and activate Ire1 phosphorylation early on after LPS stimulation, within 18 hrs. When Ire1 is activated in B cells, in addition to Xbp1 splicing, there are large-scale changes in mRNA; inhibition of the mRNA degradation function of Ire1 both reduces the number and changes the type of genes involved in altered splicing patterns, including factors for snRNA transcription. Some of the splicing changes seen at 18 hrs after LPS persist into the late stages of antibody secretion, up to 72 hrs, while others are supplanted by new splicing changes introduced by the induction of ELL2, a transcription elongation factor. ELL2 changes mRNA processing patterns and is necessary for Immunoglobulin secretion. RNA splicing patterns in antibody secreting cells are thus shaped by endo-reticular stress, ELL2 induction, and are associated with changes in the levels of snRNAs.
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Life Sciences, Molecular Biology; Boswellia serrata Roxb.; Curcuma longa L.; intestinal bowel diseases (IBD); Caco-2; PBMC; HMC-1.1; mast cells; cytokines; trans epithelial electrical resistance (TEER); reactive oxygen species (ROS)
Online: 8 November 2018 (04:53:46 CET)
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Inflammatory bowel diseases, which consist of chronic inflammatory conditions of the colon and the small intestine, are considered a global disease of our modern society. Recently, the interest toward the use of herbal therapies for the management of inflammatory bowel diseases has increased because of their effectiveness and favorable safety profile, compared to conventional drugs. Boswellia serrata Roxb. and Curcuma longa L. are amongst the most promising herbal drugs, however, their clinical use in inflammatory bowel diseases is limited and little is known on their mechanism of action. The aim of this work was to investigate the effects of two phytochemically characterized extracts of B. serrata and C. longa in an in vitro model of intestinal inflammation. Their impact on cytokine release and reactive oxygen species production, as well as the maintenance of the intestinal barrier function and on intestinal mucosa immune cells infiltration, has been evaluated. The extracts showed a good protective effect on the intestinal epithelium at 1 µg/ml, with TEER values increasing by approximately 1.5 fold, compared to LPS-stimulated cells. C. longa showed an anti-inflammatory mechanism of action, reducing IL-8, TNF-α and IL-6 production by approximately 30%, 25% and 40%, respectively, compared to the inflammatory stimuli. B. serrata action was linked to its antioxidant effect, with ROS production being reduced by 25%, compared to H2O2-stimulated Caco-2 cells. C. longa and B. serrata resulted to be promising agents for the management of inflammatory bowel diseases by modulating in vitro parameters which have been identified in the clinical conditions.
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Life Sciences, Molecular Biology; biostimulation; stress tolerance; elicitors; corona; hormesis; nutritional quality; growth promoters
Online: 6 November 2018 (05:01:51 CET)
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Biostimulants are materials that when applied in small amounts are capable of promoting plant growth. Nanoparticles (NPs) and nanomaterials (NMs) can be considered as biostimulants since, in specific ranges of concentration, generally in small levels, they increase the plant growth. Pristine NPs and NMS have a high density of surface charges capable of unspecific interactions with the surface charges of the cell walls and membranes of plant cells. In the same way, the functionalized NPs and NMS, and the NPs and NMs with a corona formed after the exposition to natural fluids such as water, soil solution, or the interior of organisms, presents a high density of surface charges that interact with specific charged groups in cell surfaces. The magnitude of the interaction will depend on the materials adhered to the corona, but the high-density charges located in a small volume causes an intense interaction capable of disturbing the density of surface charges of cell walls and membranes. The electrostatic disturbance can have an impact on the electrical potentials of the outer and inner surfaces, as well as on the transmembrane electrical potential, modifying the activity of the integral proteins of the membranes. The extension of the cellular response can range from biostimulation to cell death and will depend on the concentration, size, and the characteristics of the corona.
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Life Sciences, Molecular Biology; prefrontal cortex aging; meta-analysis of transcriptomic; synapsis aging; reactive astrogliosis
Online: 31 October 2018 (05:02:17 CET)
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Prefrontal cortex (PFC) is one of the brain regions with more prominent changes in human aging. The molecular processes related to the aging cognitive decline and mood changes are not completely understood. In order to improve our knowledge, we integrated transcriptomic data of four studies of human PFC from old people -58-80 years old- compared with young people -20-40 years old- using a meta-analytic approximation combined with molecular signature analysis. We identified 1816 differentially expressed genes -561 up-regulated and 1256 down-regulated. Pathway analysis revealed down-regulation of synaptic genes with conservation of gene expression of other neuronal regions. Additionally, we identified up-regulation of markers of astrogliosis with transcriptomic signature compatible with A1 neurotoxic astrocytes and A2 neuroprotective astrocytes. Response to interferon is related to A1 astrocytes and the A2 phenotype is mediated in aging by activation of SHH pathway and up-regulation of metallothioneins I and genes of the family EZR -ezrin, radixin, and moesin-. The main conclusions of our study are the confirmation that in aged PFC there is a global dysfunction of the synapses and we reported for the first time opposite phenotypes of astrogliosis because of brain aging.
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Life Sciences, Molecular Biology; beta-lapachone; Breast cancer stem cell; DLGAP5; Mammosphere; NQO1
Online: 30 October 2018 (09:14:35 CET)
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Background: Cancer stem cells (CSCs) exhibit self-renewal activity and give rise to other cell types in tumors. Due to the infinite proliferative potential of CSCs, drugs targeting these cells are necessary to completely inhibit cancer development. beta-lapachone (bL) has been widely used to treat cancer development, but its effect on cancer stem cells remain elusive. Thus, we investigated the effect of bL on mammosphere formation using breast cancer stem cell (BCSC) marker positive cells, MDA-MB-231. Methods: MDA-MB-231 Cells, which is negative for NQO1 expression, was constructed to stably express NQO1(NQO1 stable cells) to see the effect of bL. The effect of bL on cells were evaluated by wound healing and Transwell cell culture chambers, and ALDEFLUOR assay. Results: Here, we show that bL inhibited the proliferative ability of mammosphere derived from BCSC marker-positive cells, MDA-MB-231, in an NQO1-dependent manner. bL treatment efficiently downregulated expression level of BCSC markers CD44, ALDH1A1, and DLGAP5 that recently identified as a stem cell proliferation marker in both cultured cells and mammosphered cells. Moreover, bL efficiently downregulates cell proliferation and migration activities. Conclusions: These results strongly suggest that bL could be a therapeutic agent targeting breast cancer stem cells with proper NQO1 expression.
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Life Sciences, Molecular Biology; peptidylprolyl isomerase; chaperone; immunophilin; extremophile; intrinsic disorder
Online: 26 October 2018 (05:20:51 CEST)
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The dual-family peptidylprolyl cis-trans isomerases (immunophilins) represent naturally occurring chimera of classical FK506-binding protein (FKBP) and cyclophilin (CYN), connected by a flexible linker, and are found exclusively in monocellular organisms. The modular builds of these molecules represent two distinct types: CYN-(linker)-FKBP and FKBP-3TPR-CYN. Abbreviated respectively as CFBP and FCBP, the two classes also exhibit distinct organism preference, the CFBP being found in prokaryotes, and FCBP, in eukaryotes. This review summarizes the mystery of these unique class of prolyl isomerases, focusing on their host organisms, potential physiological role, and likely routes of evolution.
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Life Sciences, Molecular Biology; biogenesis; microRNAs; ribosomal RNA-derived fragment (rRF); ribosomes; small ribosomal RNA (srRNA); ribosomal DNA (rDNA); small RNAs
Online: 25 October 2018 (05:59:58 CEST)
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The advent of RNA-sequencing (RNA-Seq) technologies has markedly improved our knowledge and expanded the compendium of small non-coding RNAs, most of which derive from the processing of longer RNA precursors. In this review article, we will discuss about the biogenesis and function of small non-coding RNAs derived from eukaryotic ribosomal RNA (rRNA), called rRNA fragments (rRFs), and their potential role(s) as regulator of gene expression. This relatively new class of ncRNAs remained poorly investigated and underappreciated until recently, due mainly to the a priori exclusion of rRNA sequences—because of their overabundance—from RNA-Seq datasets. The situation surrounding rRFs resembles that of microRNAs (miRNAs), which used to be readily discarded from further analyses, for more than five decades, because we could not believe that RNA of such a short length could bear biological significance. As if we had not yet learned our lesson not to restrain our investigative, scientific mind from challenging widely accepted beliefs or dogmas, and from looking for the hidden treasures in the most unexpected places.
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Quante Singleton,
Kumar Vaibhav,
Molly Braun,
Andrew Khayrullin,
Bharati Mendhe,
Ravindra Kolhe,
Helen Kaiser,
Mohamed E. Awad,
Tunde Fariyike,
Ranya Elsayed,
Mohammed Elsalanty,
Carlos M. Isales,
Yutao Liu,
Mark W. Hamrick,
Krishnan M. Dhandapani,
Sadanand Fulzele
Life Sciences, Molecular Biology; extracellular vesicles, EVs , traumatic brain injury, bone loss, TBI
Online: 23 October 2018 (08:56:08 CEST)
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Traumatic brain injury (TBI) is a major source of worldwide morbidity and mortality. Patients suffering from TBI exhibit a higher susceptibility to bone loss and an increased rate of bone fractures; however, the underlying mechanisms remain poorly defined. Herein, we observed significantly lower bone quality and elevated levels of inflammation in bone and bone marrow niche after controlled cortical impact-induced TBI in in-vivo CD-1 mice. Further, we identified dysregulated NFB signaling, an established mediator of osteoclast differentiation and bone loss, within the bone marrow niche of TBI mice. Ex vivo studies revealed increased osteoclast differentiation in bone marrow-derived cells from TBI mice, as compared to sham injured mice. Finally, we found bone marrow derived extracellular vesicles (EVs) from TBI mice enhanced the colony forming ability and osteoclast differentiation efficacy of bone marrow cells and activated NFB signaling genes in bone marrow-derived cells. Taken together, we provide evidence that TBI-induced inflammatory stress on bone and the bone marrow niche may activate NFB leading to accelerated bone loss. Targeted inhibition of these signaling pathways may reverse TBI-induced bone loss and reduce fracture rates.
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Life Sciences, Molecular Biology; Sinapis alba L.; Sinapis nigra L.; ultrasound-assisted extraction; antiproliferative; proapoptotic; antimicrobial.
Online: 22 October 2018 (16:04:24 CEST)
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High Brassicaceae consumption reduces the risk of developing several cancer types, probably due to their glucosinolate amount. Extracts from Sinapis nigra L. and Sinapis alba L. have been obtained from leaves and seeds under different conditions using ethanol/water mixtures because well accepted by food industry. The EtOH/H2O 8:2 mixture gives better yields in glucosinolate amounts from grinded seeds, mainly sinalbin in S. alba and sinigrin in S. nigra. The highest antiproliferative activity in both non-tumour and tumour cell lines was induced by S. alba seeds extract. To evaluate whether Sinapis spp effect was only due to glucosinolate content or it was influenced by the extracts’ complexity, cells were treated with extracts or glucosinolates, in the presence of myrosinase. Pure sinigrin did not modify cell proliferation, while pure sinalbin was less effective than the extract. The addition of myrosinase increased the antiproliferative effects of the S. nigra extract and sinigrin. Antiproliferative activity was correlated to MAPKs modulation, which was cell and extract-dependent. Cell-cycle analysis evidenced a proapoptotic effect of S. alba on both tumour cell lines and of S. nigra only on HCT 116. Both extracts showed good antimicrobial activity in disc diffusion tests and on ready-to-eat fresh salad. These results underline the potential effects of Sinapis spp in chemoprevention and food preservation.
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Zhi-Qiang Qin,
Jing Xu,
Ting Feng,
Shan Lv,
Yin-Jun Qian,
Li-Juan Zhang,
Yin-Long Li,
Chao lv,
Robert Bergquist,
Shi-Zhu Li,
Xiao-Nong Zhou
Life Sciences, Molecular Biology; Schistosoma japonicum; Oncomelania hupensis; snail; 28S ribosomal DNA; PCR; loop-mediated isothermal amplification (LAMP); pooled samples; China
Online: 22 October 2018 (12:30:26 CEST)
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Schistosoma infection in snails can be monitored by microscopy or indirectly by sentinel mice. As both these approaches sometimes miss infections, more sensitive tests are needed, particularly in low-level transmission settings. In this study, the loop-mediated isothermal amplification (LAMP) technique, designed to detect a specific 28S ribosomal S. japonicum gene with high sensitivity, was compared to microscopy using snail samples from 51 areas endemic for schistosomiasis in five Chinese provinces. The results were compared with those by polymerase chain reaction (PCR) adding DNA sequencing as a reference when needed. The testing of pooled snail samples showed that a dilution factor of 1/50, i.e., one infected snail plus 49 non-infected ones, would still result in a positive reaction after the recommended number of amplification cycles. Testing a total of 232 pooled samples, emanating from 4,006 snail specimens, with the LAMP assay showed a 6.5% rate of infection, while traditional microscopy found only 0.04% positive samples in the same materials. Parallel PCR analysis confirmed the diagnostic accuracy of the LAMP assay, with DNA sequencing even giving LAMP a slight lead. Microscopy and the LAMP test were carried out at local schistosomiasis-control stations demonstrating that the potential of the latter assay to serve as a point-of-care (POC) test with results available within 60–90 minutes, while the more complicated PCR test had to be carried out at the National Institute of Parasitic Diseases (NIPD) in Shanghai, China. In conclusion, LAMP was found to be clearly superior to microscopy and as good as, or better, than PCR. Application of LAMP testing would be useful for surveillance and risk prediction as it requires less time than other techniques and can be used under field conditions, which improves and accelerates schistosomiasis control.
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Life Sciences, Molecular Biology; CTCF; tumour suppressor gene; haploinsufficiency; zinc finger; CRISPR/Cas9; cancer; endometrial cancer; gene editing
Online: 19 October 2018 (11:29:01 CEST)
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CCCTC-binding factor (CTCF) is a conserved transcription factor that performs diverse roles in transcriptional regulation and chromatin architecture. Cancer genome sequencing reveals diverse acquired mutations in CTCF, which we have shown, functions as a tumour suppressor gene. While CTCF is essential for embryonic development, little is known of its absolute requirement in somatic cells and the consequences of CTCF haploinsufficiency. We examined the consequences of CTCF depletion in immortalised human and mouse cells using shRNA knockdown and CRISPR/Cas9 genome editing and examined the growth and development of heterozygous Ctcf (Ctcf+/-) mice. We also analysed the impact of CTCF haploinsufficiency by examining gene expression changes in CTCF-altered endometrial carcinoma. Knockdown and CRISPR/Cas9-mediated editing of CTCF reduced the cellular growth and colony-forming ability of K562 cells. CTCF knockdown also induced cell cycle arrest and a pro-survival response to apoptotic insult. However, in p53 shRNA-immortalised Ctcf+/- MEFs we observed the opposite: increased cellular proliferation, colony formation, cell cycle progression and decreased survival after apoptotic insult compared to wild type MEFs. CRISPR/Cas9-mediated targeting in Ctcf+/- MEFs revealed a predominance of in-frame microdeletions in Ctcf in surviving clones, however protein expression could not be ablated. Examination of CTCF mutations in endometrial cancers showed locus-specific alterations in gene expression due to CTCF haploinsufficiency, in concert with downregulation of tumour suppressor genes and upregulation of estrogen-responsive genes. Depletion of CTCF expression imparts a dramatic negative effect on normal cell function. However, CTCF haploinsufficiency can have growth-promoting effects consistent with known cancer hallmarks in the presence of additional genetic hits. Our results confirm the absolute requirement for CTCF expression in somatic cells and provide definitive evidence of CTCF’s role as a haploinsufficient tumour suppressor gene. CTCF genetic alterations in endometrial cancer indicate that gene dysregulation is a likely consequence of CTCF loss, contributing to, but not solely driving cancer growth.
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Life Sciences, Molecular Biology; microRNA; mouth neoplasms; expression profile; microarray analysis.
Online: 15 October 2018 (17:59:55 CEST)
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MicroRNAs are small non-coding RNAs that are implicated in several physiological processes such as cell development, proliferation, differentiation, apoptosis, immune response and angiogenesis. In the last couple of decades, several studies on miRNA profiling in OSCC have tried to associate miRNAs with clinical characteristics such as relapse, metastasis, and survival, however, the results have been found to vary considerably, sometimes even being contradictory. The main objective of our study was to analyse and verify miRNA expression in oral squamous cell carcinoma in a Spanish population. Second, we attempted to associate the identified deregulated miRNAs with molecular pathways. 8 Oral Squamous Cell Carcinoma patients and 8 healthy control samples were analysed by a microarray Affymetrix® miRNA 4.1 array plate and validated with 8 more cases using RT-qPCR. Deregulated miRNAs were studied using Diana Tools miRPath 3.0 to associate miRNA targets with molecular pathways. Microarray analysis identified 80 deregulated miRNAs (35 over-expressed and 45 under-expressed). Only miR-497-5p and miR-4417 maintained its deregulated expression after validation with qPCR. Among the molecular pathways in which deregulated miRNAs could be implicated, the most statistically significant pathway was ‘proteoglycans in cancer’. No relationship was found between miR-497-5p or miR-4417 expression and clinical or pathological parameters except of nodular affectation (high miR-4417 expression in patients with nodular affectation, p = 0.035) and radiotherapy (diminished miR-497-5p expression in patients who needed radiotherapy, p = 0.05). We have verified the altered expression of miR-497-5p and miR-4417 in Oral Squamous Cell Carcinoma samples and related the deregulated miRNAs with the ‘proteoglycans in cancer’ pathway.
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Life Sciences, Molecular Biology; protein dynamics; coarse-grained simulation; Monte-Carlo dynamics; structural flexibility; large-scale dynamics; elastic network model;
Online: 15 October 2018 (17:10:57 CEST)
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Fluctuations of protein three-dimensional structures and large-scale conformational transitions are crucial for the biological function of proteins and their complexes. Experimental studies of such phenomena remain very challenging and therefore molecular modeling can be a good alternative or a valuable supporting tool for the investigation of large molecular systems and long-time events. In this mini-review, we present two alternative approaches to the coarse-grained (CG) modeling of dynamic properties of protein systems. We discuss two CG representations of polypeptide chains used for Monte Carlo dynamics simulations of protein local dynamics and conformational transitions and, on other hand, highly simplified structure-based Elastic Network Models of protein flexibility. In contrast to classical Molecular Dynamics the modeling strategies discussed here allow quite accurate modeling of much larger systems and longer time dynamic phenomena. We briefly describe the main features of these models and outline some of their applications, including modeling of near-native structure fluctuations, sampling of large regions of the protein conformational space, or possible support for the structure prediction of large proteins and their complexes.
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Life Sciences, Molecular Biology; red yeast rice; berberis aristate; morus alba; PCSK9
Online: 15 October 2018 (07:49:55 CEST)
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Proprotein convertase subtilisin/kexin type 9 (PCSK9) is the key regulator of low-density lipoprotein cholesterol (LDL-C) plasma levels. We previously observed that treatment of dyslipidemic subjects with nutraceutical combination containing red yeast rice (monacolin K 3.3 mg), Berberis aristata cortex extract (Berberine 531.25 mg) and Morus alba leaves extract (1-deoxynojirimycin 4 mg) (LopiGLIK®) did not alter the plasma PCSK9 levels. Thus, the aim of the present study was to investigate the effect of these three components on PCSK9 expression in HepG2 cell line in relationship to their effects on LDL-C cellular uptake. HepG2 cell line were incubated with Berberis aristata cortex extract (BCE), red yeast rice (RYR) and Morus alba leaves extract (MLE) alone or in combination for 24 h. RYR (50 µg/mL) increased PCSK9 protein expression (WB and ELISA assays), PCSK9 mRNA and its promoter activity. BCE (40 µg/mL) reduced PCSK9 expression, mRNA levels and promoter activity. MLE determined a concentration-dependent inhibition of PCSK9 at mRNA and protein levels, with a maximal reduction at 1 mg/mL; no significant changes in PCSK9 promoter activity were found. MLE also downregulates the expression of fatty acid synthase and HMG-CoA reductase mRNA levels. The combination of RYR, BCE and MLE reduced PCSK9 at mRNA, protein, and promoter activity. Finally, this combination induced the LDL receptor and LDL-C uptake by HepG2 cells. In conclusion, the positive effect of MLE on PCSK9 supports the rational of using this nutraceutical combination to control hyperlipidemic conditions.
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Life Sciences, Molecular Biology; children, immunology, miRNA, partial remission phase, type 1 diabetes
Online: 5 October 2018 (09:29:15 CEST)
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The objective of this study was to identify circulating miRNAs affected by disease duration in newly diagnosed children with type 1 diabetes. Forty children and adolescents from The Danish Remission Phase Cohort were followed with blood samples drawn at 1, 3, 6, 12 and 60 months after diagnosis. Pancreatic autoantibodies were measured at each visit. Cytokines were measured only the first year. miRNA expression profiling was performed by RT-qPCR and quantified for 179 human plasma miRNAs. The effect of disease duration was analyzed by mixed models for repeated measurements, adjusted for sex and age. Eight miRNAs (hsa-miR-10b-5p, hsa-miR-17-5p, hsa-miR-30e-5p, hsa-miR-93-5p, hsa-miR-99a-5p, hsa-miR-125b-5p, hsa-miR-423-3p and hsa-miR-497-5p) were found to significantly change expression (adjusted p-value < 0.05) with disease progression. Three pancreatic autoantibodies ICA, IA-2A, GADA65 and 4 cytokines IL-4, IL-10, IL-21, IL-22 were associated with the miRNAs at different time points. Pathway analysis revealed association with various immune-mediated signaling pathways. Eight miRNAs, involved in immunological pathways changed expression levels during the first five years after diagnosis in children with type 1 diabetes, and were associated with variations in cytokine and pancreatic antibodies, suggesting a possible effect on the immunological processes in the early phase of the disease.
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Life Sciences, Molecular Biology; Unfolded protein response; ER morphology; Mitochondria-associated ER membrane; ER-PM contact sites
Online: 2 October 2018 (13:41:17 CEST)
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The function of the endoplasmic reticulum (ER) can be impaired by the alternation of the extra- and intracellular environment such as disruption of calcium homeostasis, expression of mutated proteins and oxidative stress. In response to disruptions to ER homeostasis, eukaryotic cells activate canonical branches of signal transduction cascades, collectively termed the unfolded protein response (UPR). The UPR attempts to recover the protein folding capacity and avoid irreversible cellular damage. Additionally, the UPR has been shown to play unique physiological roles in the regulation of diverse cellular events, including cell differentiation and development and lipid biosynthesis. Recent studies have indicated that these important cellular events are also regulated by contact and communication among organelles. These reports suggest strong involvement among the UPR, organelle communication and regulation of cellular homeostasis. However, the precise mechanisms for the formation of contact sites and the regulation of its dynamics by UPR remain unresolved. In this review, we summarized the current understanding of how the UPR regulates morphological changes to the ER and the formation of contact sites between the ER and other organelles. We also review how UPR-dependent connections between the ER and other organelles affect cellular and physiological functions.
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Life Sciences, Molecular Biology; Unfolded protein response; ER morphology; Mitochondria-associated ER membrane; ER-PM contact sites
Online: 26 September 2018 (15:44:54 CEST)
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The function of the endoplasmic reticulum (ER) can be impaired by the alternation of the extra- and intracellular environment such as disruption of calcium homeostasis, expression of mutated proteins and oxidative stress. In response to disruptions to ER homeostasis, eukaryotic cells activate canonical branches of signal transduction cascades, collectively termed the unfolded protein response (UPR). The UPR attempts to recover the protein folding capacity and avoid irreversible cellular damage. Additionally, the UPR has been shown to play unique physiological roles in the regulation of diverse cellular events, including cell differentiation and development and lipid biosynthesis. Recent studies have indicated that these important cellular events are also regulated by contact and communication among organelles. These reports suggest strong involvement among the UPR, organelle communication and regulation of cellular homeostasis. However, the precise mechanisms for the formation of contact sites and the regulation of its dynamics by UPR remain unresolved. In this review, we summarized the current understanding of how the UPR regulates morphological changes to the ER and the formation of contact sites between the ER and other organelles. We also review how UPR-dependent connections between the ER and other organelles affect cellular and physiological functions.
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Life Sciences, Molecular Biology; Dormant origins; replicative stress; replication timing; DNA damage; genome instability; cancer
Online: 21 September 2018 (16:00:30 CEST)
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Maintenance of the human chromosomes stability requires a tight regulation of DNA replication to duplicate once and only once the entire genome of a single cell. In mammalians cells, origin activation is controlled in space and time by a cell specific and robust program called replication timing. About 100 000 of potential origins are loaded onto the chromatin at the G1 phase but only 20-30% are selected and active during the replication of a given cell. When the replication fork is slowed down by exogenous or endogenous sources, the cell need to activate more origins to complete the replication on time. Thus, the large choice of origins that can be activated may be a key player in the protection of the genome. The aim of this review is to discuss about the role of these dormant origins as housekeepers of the human genome in response to replicative stress.
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Life Sciences, Molecular Biology; Oxidative stress; blackcurrant; biofunctional cookie; simulated digestion; bioactive metabolites; inflammatory cytokines
Online: 17 September 2018 (15:05:44 CEST)
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The improved understanding of the underlying mechanisms of oxidative damage and/or chronic diseases is of high priority in dietary research. Although the chemical extraction of biofunctional molecules from different fruits and cereals have been studied extensively, the impact of food processing and digestion on bioactivity has not been studied systematically. The aim of this study was to investigate the biofunctional potential of blackcurrant powder incorporated into wholemeal wheat and barley cookies in after simulated in vitro digestion. The incorporation of blackcurrant significantly (p<0.05) increased the total phenolic content (about 60 %), significantly improved oxygen radical absorbance capacity (about 25 %) of the cookie digesta. Additionally cellular antioxidant and anti-proliferative activity (lowest EC₅₀ value 1.02 mg/mL) on human liver cancer cell model, HepG2 was significantly enhanced. Bioactive metabolites of blackcurrant incorporated cookies were significantly supressed the inflammatory cytokine genes IL-1β (about 3-fold), IL-6 (about 0.5-fold) and NF-kB (about 2-fold) regulation and upregulated satiety gene NUCB-2/Nesfatin-1 (about 5-fold) compare with wholemeal wheat and barley control cookies. The exerted synergistic effects of this study suggest that there may be a new and effective option to prevent and control chronic diseases in human.
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Life Sciences, Molecular Biology; breast cancer; metastasis; Notch; Jagged-1; Dll4
Online: 17 September 2018 (11:54:19 CEST)
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Metastasis is a major cause factor for breast cancer (BC)-associated mortality. During the metastatic process, disseminated tumor cells (DTCs) detach from the primary sites, and enter the bloodstream and establish the secondary colonies. Recent studies have provided substantial evidence for the importance of Notch signaling in BC metastasis. Therefore, this review focuses on the mechanisms by which Notch contributes to the origin of BC DTCs, increases their motility, regulates their intravasation and extravasation, protects them from host surveillance, and finally facilitates colonization. Identification of the mechanisms underlying Notch-related BC metastasis will lead to the development of novel Notch-targeted therapeutic strategies to reduce metastasis and significantly improve outcomes.
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Life Sciences, Molecular Biology; Keywords: 1; genome 2; epigenetics 3; neurodevelopmental disorders; 4; chromosome anomalies; 5; retrotransposon; 6; chromosome rearrangement; 7; neurologic disease; 8; birth defects; 9; development 10; infection
Online: 15 September 2018 (18:07:03 CEST)
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Abstract: The purpose of this study was to understand the role of infection in the origin of chromosomal anomalies linked to neurodevelopmental disorders. In patients with neurodevelopmental disorders, DNA’s from viruses and bacteria including known teratogens were tested against chromosome anomalies known to cause the disorders. Results support a theory that parental infections disrupt elaborate multi-system gene coordination needed for neurodevelopment. Genes essential for neurons, lymphatic drainage, immunity, circulation, angiogenesis, barriers, structure, and chromatin activity were all found close together in polyfunctional clusters that were deleted in neurodevelopmental disorders. These deletions account for immune, circulatory, and structural deficits that accompany neurologic deficits. In deleted clusters, specific and repetitive human DNA matched infections and passed rigorous artifact tests. In some patients, epigenetic driver mutations were found and may be functionally equivalent to deleting a cluster or changing topologic chromatin interactions because they change access to large chromosome segments. In three families, deleted DNA sequences were associated with intellectual deficits and were not included in any database of genomic variants. These sequences were thousands of bp and unequivocally matched foreign DNAs. Analogous homologies were also found in chromosome anomalies of a recurrent neurodevelopmental disorder. Viral and bacterial DNAs that match repetitive or specific human DNA segments are thus proposed to interfere with highly active break repair during meiosis, and sometimes delete polyfunctional clusters, and disable epigenetic drivers. Mis-repaired gametes produce zygotes containing rare chromosome anomalies which cause neurologic disorders and accompanying non-neurologic signs. Neurodevelopmental disorders may be examples of assault on the human genome by foreign DNA with some infections more likely tolerated because they resemble human DNA segments. Further tests of this model await new technology.
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Anna Picca,
Giuseppe Sirago,
Vito Pesce,
Angela Maria Serena Lezza,
Riccardo Calvani,
Maurizio Bossola,
Emanuele Rocco Villani,
Francesco Landi,
Christiaan Leeuwenburgh,
Christy Carter,
Roberto Bernabei,
Emanuele Marzetti
Life Sciences, Molecular Biology; mitochondrial quality control, mitochondrial biogenesis, mitochondrial dynamics, mitophagy, mtDNA, TFAM binding, oxidative lesions, mtDNA damage, cardioprotection, peroxiredoxin
Online: 13 September 2018 (11:36:07 CEST)
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Mitochondrial dysfunction is relevant mechanism in cardiac aging. Here, we investigated the effects of late-life enalapril administration at non-antihypertensive dose on mitochondrial genomic stability, oxidative damage, and mitochondrial quality control (MQC) signaling in the heart of aged rats. The protein expression of selected mediators (i.e., mitochondrial antioxidant enzymes, energy metabolism, mitochondrial biogenesis, dynamics, and autophagy) was measured in old rats randomly assigned to receive enalapril (n=8) or placebo (n=8) from 24 to 27 months of age. We also assessed mitochondrial DNA (mtDNA) content, citrate synthase activity, oxidative lesions to protein and mtDNA (i.e., carbonyls and abundance of mtDNA4834 deletion), and mitochondrial transcription factor A (TFAM) binding to specific mtDNA regions. Enalapril attenuated cardiac hypertrophy and oxidative stress-derived damage (mtDNA oxidation, mtDNA4834 deletion, and protein carbonylation), while increasing mitochondrial antioxidant defenses. TFAM binding to mtDNA regions involved in replication and deletion generation was increased following enalapril administration. Increased mitochondrial mass as well as mitochondriogenesis and autophagy signaling was found in enalapril-treated rats. Late-life enalapril administration mitigates age-dependent cardiac hypertrophy and oxidative damage, while increasing mitochondrial mass and modulating MQC signaling. Further analyses are needed to conclusively establish whether enalapril may offer cardioprotection during aging.
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Life Sciences, Molecular Biology; Suprachiasmatic nucleus (SCN); Circadian clock; Soleus Muscle (SM); Brown adipose tissue (BAT); liver; 6-meal feeding; Respiratory exchange ratio (RER); Clock genes; metabolic genes; Shift work.
Online: 11 September 2018 (14:21:48 CEST)
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Restricted feeding is well known to affect expression profiles of both clock and metabolic genes. However, it is unknown whether these changes in metabolic gene expression result from changes in the molecular clock or in feeding behavior. Here we eliminated the daily rhythm in feeding behavior by providing 6-meals evenly distributed over the light/dark-cycle. Animals on this 6-meals-a-day feeding schedule retained the normal day/night difference in physiological parameters including body temperature and locomotor activity. The daily rhythm in respiratory exchange ratio (RER), however, was significantly phase-shifted through increased utilization of carbohydrates during the light phase and increased lipid oxidation during the dark phase. This 6-meals-a-day feeding schedule did not have a major impact on the clock gene expression rhythms in the master clock but did have mild effects on peripheral clocks. By contrast, genes involved in glucose and lipid metabolism showed differential expression. Concluding, eliminating the daily rhythm in feeding behavior in rats does not affect the master clock and only mildly affects peripheral clocks, but disturbs metabolic rhythms in liver, skeletal muscle and brown adipose tissue in a tissue-dependent manner. Thereby a clear daily rhythm in feeding behavior strongly regulates timing of peripheral metabolism, separately from circadian clocks.
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Life Sciences, Molecular Biology; nucleolus; RRN3; I-kappaB; stress; aspirin; CDK4; RelA; p65; cancer; neurodegenerative disorders
Online: 4 September 2018 (04:49:10 CEST)
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Nucleoli are emerging as key sensors of cellular stress and regulators of the downstream consequences on proliferation, metabolism, senescence and apoptosis. NF-kB signalling is activated in response to a similar plethora of stresses, which leads to modulation of cell growth and death programs. Although these pathways are distinct, it is increasingly apparent that they converge at multiple levels. Exposure of cells to certain insults causes a specific type of nucleolar stress that is characterised by degradation of the PolI complex component, TIF-IA, and increased nucleolar size. Recent studies have shown that this atypical nucleolar stress lies upstream of cytosolic IkB degradation and NF-kB nuclear translocation. Under these stress conditions, the RelA component of NF-kB accumulates within functionally altered nucleoli to trigger a nucleophosmin dependent, apoptotic pathway. In this review, we will discuss these points of crosstalk and their relevance to the anti-tumour mechanism of aspirin and small molecule CDK4 inhibitors. We will also briefly discuss how NF-kB-nucleoli crosstalk may be more broadly relevant to the regulation of cellular homeostasis and how it may be exploited for therapeutic purpose.
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Life Sciences, Molecular Biology; Proteostasis, translation, neurodegeneration, mtUPR, UPR, stress granules, ATF4
Online: 3 September 2018 (11:54:16 CEST)
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The tremendous diversity and complexity of proteins invariably results in protein misfolding, to which cells have evolved numerous mechanisms of mitigating. Degrading misfolded proteins is perhaps the most intuitive strategy, but also critical to managing proteostasis are the elaborate mechanisms of translational control. Attenuated rates of translation ameliorate protein misfolding by downregulating the flux of new protein and conserving ATP. Loss of translational control, particularly in neurons, constitutes a major proteostatic dysfunction capable of causing or exacerbating neurodegeneration, while interventions aimed at downregulating protein synthesis are generally neuroprotective. In this review, I examine the critical neuronal signaling networks employed to control translation with an emphasis on current research. This includes the Unfolded Protein Response (UPR), the mitochondrial UPR (mtUPR), mTORC1 signaling, and stress granule formation.
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Life Sciences, Molecular Biology; SIRT6, Diabetes, Gluconeogenesis, Cancer, Aging, Heart Disease, Pharmacological SIRT6 Inhibitor, Cardiac Hypertrophy, Tumorigenesis, Neurodegeneration, Neurodegenerative Diseases, AD
Online: 29 August 2018 (13:04:23 CEST)
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SIRT6 is a NAD+ dependent enzyme and stress response protein that has sparked the curiosity of a plethora of researchers in different branches of the biomedical sciences. A unique member of the known Sirtuin family, SIRT6 has several different functions in several different molecular pathways related to DNA repair, glycolysis, gluconeogenesis, tumorigenesis, neurodegeneration, cardiac hypertrophic responses and so on. Only in recent times however did the potential usefulness of SIRT6 come to light as we learned more about its biochemical activity, regulation, biological roles and structure [1]. Even until very recently, SIRT6 was known more for chromatin signaling but being a nascent topic of study, more information has been ascertained and its potential involvement in major human diseases namely, diabetes, cancer, neurodegenerative diseases and heart disease has been demonstrated. It is pivotal to explore the mechanistic workings of SIRT6 since future research may hold the key to engendering strategies, involving SIRT6, that may have significant implications for human health and expand upon possible treatment options. In this review, we are primarily concerned with exploring the latest understanding of SIRT6 and how it can alter the course of several life-threatening diseases that cripple today’s society such as processes related to aging, cancer, neurodegenerative diseases, heart disease and diabetes. In addition, SIRT6 has shown to be involved in liver disease, inflammation and bone related issues but more emphasis is given to the former. Lastly, any recent promising pharmacological investigations and study of potential therapeutic targets are also delineated in this review.
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Life Sciences, Molecular Biology; epigenetics, rehabilitation, DNA methylation, histone modification, HDAC, exercise, health span, heart failure, neurodegeneration, cancer, lung fibrosis, bone formation.
Online: 27 August 2018 (15:58:21 CEST)
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A large body of evidence reports about the positive effects of physical activity in pathophysiological conditions associated with aging. Physical exercise, alone or in combination with other medical therapies, unquestionably causes reduction of symptoms in chronic non-transmissible diseases often leading to significant amelioration or complete healing. The molecular basis of this exciting outcome, however, remain largely obscure. Epigenetics, exploring at the interface between environmental signals and the remodelling of chromatin structure, promises to shed light on this intriguing matter possibly contributing to the identification of novel therapeutic targets. In this review, we shall focalize on the role of sirtuins (Sirts) a class III histone deacetylases (HDACs) which function has been frequently associated, often with a controversial role, to the pathogenesis of aging-associated pathophysiological conditions including cancer, cardiovascular, muscular, neurodegenerative, bones and respiratory diseases. Numerous studies, in fact, demonstrate that Sirt-dependent pathways are activated upon physical and cognitive exercises linking mitochondrial function, DNA structure remodelling and gene expression regulation to designed medical therapies leading to tangible beneficial outcomes. However, in similar conditions, other studies assign to sirtuins a negative pathophysiological role. In spite of this controversial effect, it is doubtless that studying sirtuins in chronic diseases might lead to an unprecedented improvement of life quality in the elderly.
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Life Sciences, Molecular Biology; osteoarthritis; RNA-seq; STR/ort; C57BL/6; MRL/MpJ; ACL injury; PTOA; regeneration; inflammation; B4galnt2
Online: 14 August 2018 (05:47:38 CEST)
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Injuries to the anterior cruciate ligament (ACL) often result in post-traumatic osteoarthritis (PTOA). To better understand the molecular mechanisms behind PTOA development following ACL injury, we profiled ACL injury-induced gene expression changes in knee joints of three mouse strains with varying susceptibility to OA: STR/ort (highly susceptible), C57BL/6 (moderately susceptible) and super-healer MRL/MpJ (not susceptible). Right knee joints of the mice were injured using a non-invasive tibial compression injury model that closely mimics ACL rupture in humans and global gene expression was quantified before and at 1-day, 1-week, and 2-weeks post-injury using RNA-seq. Following injury, STR/ort displayed severe cartilage degeneration while MRL/MpJ had little cartilage damage. Gene expression analysis suggested that prolonged inflammation and elevated catabolic activity in STR/ort injured joints, compared to the other two strains may be responsible for the severe PTOA phenotype observed in this strain. MRL/MpJ had the lowest expression values for several inflammatory cytokines and catabolic enzymes activated in response to ACL injury. Furthermore, we identified several genes highly expressed in MRL/MpJ compared to the other two strains including B4galnt2 and Tpsab1 which may contribute to enhanced healing in the MRL/MpJ. Overall, this study has increased our knowledge of early molecular changes associated with PTOA development.
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Jessica Maiuolo,
Micaela Gliozzi,
Vincenzo Musolino,
Miriam Scicchitano,
Cristina Carresi,
Federica Scarano,
Francesca Bosco,
Saverio Nucera,
Stefano Ruga,
Maria Caterina Zito,
Rocco Mollace,
Ernesto Palma,
Massimo Fini,
Carolina Muscoli,
Vincenzo Mollace
Life Sciences, Molecular Biology; brain blood barrier; endothelial dysfunction; neurodegeneration
Online: 13 August 2018 (08:59:21 CEST)
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The main neurovascular unit of the Blood Brain Barrier (BBB) consists of a cellular component, which includes endothelial cells, astrocytes, pericytes, microglia, neurons and oligodendrocytes, as well as a non-cellular component resulting from the extracellular matrix. The endothelial cells are the major vital component of the BBB able to preserve the brain homeostasis; these cells are situated along the demarcation line between the bloodstream and the brain. Therefore, an alteration or the progressive disruption of the endothelial layer may clearly impair the brain homeostasis. The proper functioning of the brain endothelial cells is generally ensured by two elements: 1) the presence of junction proteins; 2) the preservation of a specific polarity involving an apical-luminal and a basolateral-abluminal membrane. In view of the above, this review intends to identify the molecular mechanisms underlying BBB function and their changes occurring in early stages of neurodegenerative processes in order to develop novel therapeutic strategies aimed to counteract neurodegenerative disorders.
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Life Sciences, Molecular Biology; cryptotanshinone; NSCLC; cell cycle arrest; apoptosis; PI3K/Akt/GSK3β
Online: 2 August 2018 (09:05:32 CEST)
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Cryptotanshinone (CTT) is a natural product and a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miltiorrhiza bunge. Notably, CTT has a variety of anti-cancer actions, including the activation of apoptosis, anti-proliferation, and a reduction in angiogenesis. We further investigated the anti-cancer effects of CTT in A549 and H460 which are NSCLC cell lines. CTT treatment in NSCLC cells reduced cell growth through PI3K/Akt/GSK3β pathway inhibition, G0 / G1 cell cycle arrest, and the activation of apoptosis. CTT induced increase of Bax and cleavage of apoptosis-related signaling such as caspase-3, caspase-9, poly-ADP-ribose polymerase (PARP), and Bax, as well as inhibition of anti-apoptosis related signaling such as Bcl-2, survivin, and cellular-inhibitor of apoptosis protein 1 and 2 (cIAP-1 and -2). It also induced G0/G1 phase cell cycle arrest by decreasing the expression of cyclin A, cyclin D, cyclin E, Cdk 2, and Cdk 4. In addition, CTT reduced the protein expression of the PI3K/Akt/GSK3β signaling pathway related to cell proliferation. These results highlight the latent potential of CTT as natural therapeutic agent for NSCLC.
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Life Sciences, Molecular Biology; spinal cord injury; inflammation; plasma
Online: 20 July 2018 (12:49:20 CEST)
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While over half of all spinal cord injuries (SCIs) occur in the cervical region, the majority of preclinical studies have focused on models of thoracic injury. However, these two levels are anatomically distinct—with the cervical region possessing a greater vascular supply, grey-white matter ratio and sympathetic outflow relative to the thoracic region. As such, there exists a significant knowledge gap in the secondary pathology at these levels following SCI. In this study, we characterized the systemic plasma markers of inflammation over time (1, 3, 7, 14, 56 days post-SCI) after moderate-severe, clip-compression cervical and thoracic SCI in the rat. Using high-throughput ELISA panels, we observed a clear level-specific difference in plasma levels of VEGF, leptin, IP10, IL18, GCSF, and fractalkine. Overall, cervical SCI had reduced expressions of both pro- and anti-inflammatory proteins relative to thoracic SCI, likely due to sympathetic dysregulation associated with higher level SCIs. However, contrary to the literature, we did not observe level-dependent splenic atrophy with our incomplete SCI model. This is the first study to compare the systemic plasma-level changes following cervical and thoracic SCI using level-matched and time-matched controls. The results of this study provide the first evidence in support of level-targeted intervention and also challenge the phenomenon of high SCI-induced splenic atrophy in incomplete SCI models.
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Life Sciences, Molecular Biology; MicroRNA; osteoprotegerin (OPG); orthodontic tooth movement (OTM); miR-3198; mechanical stresses; periodontal ligament cells (PDL cells); compression; tension
Online: 18 July 2018 (08:58:19 CEST)
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Background: Osteoclastic bone resorption in the compression zone of periodontal ligament (PDL) plays a role in orthodontic tooth movement, and is regulated by the balance of RANKL and OPG. Compression downregulates OPG, conversely, tension upregulates OPG in PDL cells. However, the regulatory mechanism of OPG expression in PDL cells under different mechanical stresses remains unclear. Methods: To study microRNA (miRNA) expression profiles, compression (2g/cm2) or tension (15%-elongation) was applied to immortalized human PDL (HPL) cells, and miRNA was extracted. The miRNA expression was analyzed using a human miRNA microarray, and the changes of the miRNA expression were confirmed by real-time RT-PCR. In addition, miR-3198-mimic and -inhibitor were transfected into HPL cells to understand the resulting OPG expression and production. Results: Certain miRNAs were expressed differentially under compression and tension. Some miRNAs including miR-3198 were upregulated only by compression. Real-time RT-PCR confirmed that compression induced miR-3198, but tension reduced it, in HPL cells. miR-3198-inhibitor upregulated and miR-3198-mimic reduced OPG in HPL cells. miR-3198-inhibitor rescued the compression-mediated downregulation of OPG. On the other hand, miR-3198-mimic reduced OPG expression under tension. Conclusion: We conclude that miR-3198 is upregulated by compression and is downregulated by tension, suggesting that miR-3198 downregulates OPG in response to mechanical stress.
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Life Sciences, Molecular Biology; PCR, recombination, cloning, engineering, biotechnology, synthetic biology, synthetic nucleotide, plasmids, repository, minimalism, Escherichia coli, mutagenesis
Online: 16 July 2018 (12:52:38 CEST)
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Minimal plasmids play an essential role in many intermediate steps in molecular biology. They can for example be used to assemble building blocks in synthetic biology or be used as intermediate cloning plasmids that are ideal for PCR-based mutagenesis methods. A small backbone also opens up for additional unique restriction enzyme cloning sites. Here we describe the generation of a ~1kb fully functional cloning plasmid with an extended multiple cloning site (MCS). To our knowledge, this is the smallest high-copy cloning vector ever described.
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Life Sciences, Molecular Biology; tau protein amyloids; Alzheimer’s disease; tauopathy
Online: 16 July 2018 (10:49:49 CEST)
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Abnormal filamentous aggregates formed by tangled tau protein turn out to be classic amyloid fibrils, meeting all criteria defined under the fuzzy oil drop model in the context of amyloid characterization. The model recognizes amyloids as linear structures where local hydrophobicity minima and maxima propagate in an alternating manner along the fibril’s long axis. This distribution of hydrophobicity differs greatly from the classic monocentric hydrophobic core observed in globular proteins. Rather than becoming a globule, the amyloid instead forms a ribbonlike (or cylindrical) structure, which can be thought of as a distorted spherical micelle, which in limit form appears to be the ribbon-like micelle.
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Life Sciences, Molecular Biology; molecular dynamics simulation; 17β-estradiol; DNA-aptamer; GROMACS; modeling
Online: 12 July 2018 (11:29:54 CEST)
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Micro-pollutants such as 17β-Estradiol (E2) have been detected in different water resources and their negative effects on the environment and organisms have been observed. Aptamers are established as a possible detection tool, but the underlying ligand binding is largely unexplored. In this study, a previously described 35-mer E2-specific aptamer was used to analyse the binding characteristics between E2 and the aptamer with a MD simulation in an aqueous medium. Because there is no 3D structure information available for this aptamer, it was modeled using coarse-grained modeling method. The E2 ligand was positioned inside a potential binding area of the predicted aptamer structure, the complex was used for an 25 ns MD simulation, and the interactions were examined for each time step. We identified E2-specific bases within the interior loop of the aptamer and also demonstrated the influence of frequently underestimated water-mediated hydrogen bonds. The study contributes to the understanding of the behavior of ligands binding with aptamer structure in an aqueous solution. The developed workflow allows generating and examining further appealing ligand-aptamer complexes.
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Life Sciences, Molecular Biology; HIF; NF-kappaB; EPAS1; LIGHT; TNFSF14; p52; NIK; ChIP
Online: 2 July 2018 (09:53:29 CEST)
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Non-canonical NF-kB signalling plays important roles in development and function of the immune system but also is deregulated in a number of inflammatory diseases. Although, NF-kB and HIF crosstalk has been documented, this has only been described following canonical NF-kB stimulation, involving RelA/p50 and the HIF-1 dimer. Here we report that the non-canonical inducer TNFSF14/LIGHT leads to HIF induction and activation in cancer cells. We demonstrate that only HIF-2a is induced at the transcriptional level following non-canonical NF-kB activation, via a mechanism dependent on the p52 subunit. Furthermore, we demonstrate that p52 can bind to the HIF-2a gene in cells. These results indicate that non-canonical NF-kB can lead to HIF signalling implicating HIF-2a as one of the downstream effectors of this pathway in cells.
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Life Sciences, Molecular Biology; α-synuclein; amyloid fibrils; fibrillogenesis; thioflavin T; equilibrium microdialysis; binding parameters; structural polymorphism
Online: 28 June 2018 (10:50:40 CEST)
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In this work α-synuclein amyloid fibrils, formation of which is a biomarker of the Parkinson’s disease, were investigated with the use of fluorescent probe thioflavin T (ThT). Experimental conditions of the protein fibrillogenesis were chosen so that a sufficient number of continuous measurements can be performed to characterize and analyze all stages of this process. The reproducibility of fibrillogenesis and the structure of the obtained aggregates (that is a critical point for their further investigation) were proved using a wide range of physical-chemical methods. For determination of ThT—α-synuclein amyloid fibrils binding parameters sample and reference solutions were prepared with the use of equilibrium microdialysis. By absorption spectroscopy of these solutions ThT—fibrils binding mode with the binding constant about 104 M−1 and stoichiometry of ThT per protein molecule about 1:8 was observed. Fluorescence spectroscopy of the same solutions with the subsequent correction of the recorded fluorescence intensity on the primary inner filter effect allowed to determine another mode of ThT binding to fibrils with the binding constant about 106 M−1 and stoichiometry about 1:2500. Analysis of photophysical characteristics of the dye molecules bound to the sites of different binding modes allowed to assume the possible localization of these sites. Obtained differences in the ThT binding parameters to amyloid fibrils formed from α-synuclein and other amyloidogenic proteins, as well as in the photophysical characteristics of the bound dye, confirmed the hypothesis of amyloid fibrils polymorphism.
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Life Sciences, Molecular Biology; Kummerowia striata; anti-oxidant activity; melanin synthesis; p-coumaric acid; quercetin
Online: 21 June 2018 (14:44:02 CEST)
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Kummerowia striata is a traditional medicine used for the therapy of inflammation-related diseases. Herein, we investigated the anti-melanogenic and antioxidant activities of an ethanolic extract of K. striata (EKS) using a number of in vitro and cell culture model systems. The anti-melanogenic effect was assessed in B16F10 melanoma cells based on melanin synthesis and in vitro tyrosinase inhibitory activity and the anti-oxidant activity assays were performed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2ʹ-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS); EKS exhibited strong anti-oxidant activities in both the assays. The expression of tyrosinase, tyrosinase-related protein 1, tyrosinase-related protein 2, and microphthalmia-associated transcription factor was decreased in a dose-dependent manner at mRNA and protein levels upon treatment with EKS. Notably, EKS did not affect the cell viability at all the EKS concentrations used in this study, indicating that EKS-mediated inhibition of melanin synthesis is not accompanied with cytotoxicity. Collectively, our findings demonstrate, for the first time, that EKS possesses anti-melanogenic and anti-oxidant activities, and suggest that further evaluation and development of EKS as a functional supplement or cosmetic might be useful for skin whitening and for reduction wrinkles.
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Life Sciences, Molecular Biology; ovarian cancer; cancer stem cells; signaling, chemoresistance, metastasis
Online: 15 June 2018 (15:14:22 CEST)
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Ovarian cancer is the most lethal gynecological malignancy. Poor overall survival, particularly for patients with high grade serous (HGS) ovarian cancer, are often attributed to late stage at diagnosis and relapse following chemotherapy. HGS ovarian cancer is a heterogenous disease in that few genes are consistently mutated between patients. Additionally, HGS ovarian cancer is characterized by high genomic instability. For these reasons personalized approaches may be necessary for effective treatment and cure. Understanding the molecular mechanisms that contribute to tumor metastasis and chemoresistance are essential to improve survival rates. One favored model for tumor metastasis and chemoresistance is the cancer stem cell (CSC) model. CSCs are cells with enhanced self-renewal properties that are enriched following chemotherapy. Elimination of this cell population is thought to be a mechanism to increase therapeutic response. Therefore, accurate identification of stem cell populations that are most clinically relevant is necessary. While many CSC identifiers (ALDH, OCT4, CD133, and side population) have been established, it is still not clear which population(s) will be most beneficial to targeted in patients. Therefore, there is a critical need to characterize CSCs with reliable markers and find their weaknesses that will make the CSCs amenable to therapy. Many signaling pathways are implicated for their roles in CSC initiation and maintenance. Therapeutically targeting pathways needed for CSC initiation or maintenance may be an effective way of treating HGS ovarian cancer patients. In conclusion, the prognosis for HGS ovarian cancer may be improved by combining CSC phenotyping with targeted therapies for pathways involved in CSC maintenance.
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Life Sciences, Molecular Biology; Clostridium botulinum; botulinum neurotoxin; serotype F; subtype; VAMP-2; synaptobrevin; Zn2+ protease
Online: 15 June 2018 (05:32:49 CEST)
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In the recent past about 40 botulinum neurotoxin (BoNT) subtypes belonging to serotypes A, B, E, and F pathogenic to humans were identified among hundreds of independent isolates. BoNTs are the etiological factors of botulism and represent potential bioweapons, but are also recognized pharmaceuticals for efficient counteraction of hyperactive nerve terminals in a variety of human diseases. The detailed biochemical characterization of subtypes as the basis for development of suitable countermeasures and possible novel therapeutic applications is lagging behind the increase in new subtypes. Here we report the primary structure of a ninth subtype of BoNT/F. Its amino acid sequence diverges by at least 8.4% at the holotoxin and 13.4% on the enzymatic domain level from all other known BoNT/F subtypes. We found that BoNT/F9 shares the scissile Q58/K59 bond in its substrate vesicle associated membrane protein 2 with the prototype BoNT/F1. Comparative biochemical analyses of four BoNT/F enzymatic domains showed that the catalytic efficiencies decrease in the order F1 > F7 > F9 > F6 and vary by up to factor eight. KM values increase in the order F1 > F9 > F6 ≈ F7, whereas kcat decreases in the order F7 > F1 > F9 > F6. Comparative substrate scanning mutagenesis studies revealed a unique pattern of crucial substrate residues for each subtype. Based upon structural coordinates of F1 bound to an inhibitor polypeptide the mutational analyses suggest different substrate interactions in the substrate binding channel of each subtype.
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Life Sciences, Molecular Biology; miR-29a; cholestasis; apoptosis; ER stress; toll like receptors; epigenetics
Online: 11 June 2018 (14:03:48 CEST)
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Both fibrosis and cirrhosis of the liver are the end results of most kinds of chronic liver damage and present a common but difficult clinical challenge throughout the world. The inhibition of the fibrogenic, proliferative, and migratory effects of hepatic stellate cells (HSCs) has become an experimental therapy for preventing and even reversing hepatic fibrosis. Furthermore, a complete understanding of the function of non-coding RNA-mediated epigenetic mechanisms in HSC activation may improve our perception of liver fibrosis pathogenesis. This review focuses on an evolving view of molecular mechanisms in which HSC activation by miR-29a signaling may moderate their profibrogenic phenotype, thus supporting the use of miR-29a agonists as a potential therapy for treating liver fibrosis in the future.
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Simone Pippa,
Cecilia Mannironi,
Valerio Licursi,
Luca Bombardi,
Gianni Colotti,
Enrico Cundari,
Adriano Mollica,
Antonio Coluccia,
Valentina Naccarato,
Giuseppe La Regina,
Romano Silvestri,
Rodolfo Negri
Life Sciences, Molecular Biology; histone demethylase inhibitors; DNA damage; epigenetic drugs; breast cancer
Online: 8 June 2018 (12:29:10 CEST)
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Background: KDM5 enzymes are H3K4 specific histone demethylases involved in transcriptional regulation and DNA repair. These proteins are over-expressed in different kinds of cancer, including breast, prostate and bladder carcinoma, with positive effects on cancer proliferation and chemo-resistance. For these reasons, these enzymes are potential therapeutic cancer targets. Methods: In the present study, we analyzed the effects of three different inhibitors of KDM5 enzymes in MCF-7 breast cancer cells over-expressing JARID1B. In particular we tested H3K4 demethylation (western blot); target gene transcription (RNAseq and real time PCR); radio-sensitivity (citoxicity and clonogenic assays) and damage accumulation (kinetics of H2AX phosphorylation). Results: we show that two compounds with completely different chemical structure can selectively inhibit KDM5 enzymes and that both compounds are capable of increasing sensitivity of breast cancer cells to ionizing radiation and H2AX phosphorylation. Conclusions: These findings confirm the involvement of H3K4 specific demethylases in DNA damage signaling and repair and suggest new strategies for the therapeutic use of their inhibitors.
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Life Sciences, Molecular Biology; feed-forward loop (FFL); cAMP receptor protein (CRP); transcriptional factor (TF).
Online: 6 June 2018 (16:00:56 CEST)
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The feed-forward loop (FFL) is an important and basic network motif to understand specific biological functions. Cyclic-AMP (cAMP) receptor protein (CRP), a transcription factor (TF), mediates catabolite repression and regulates more than 400 genes in response to changes in intracellular concentrations of cAMP in Escherichia coli. CRP participates in some FFLs like araBAD and araFGH operons and adapt to fluctuating environmental nutrients thus enhancing the survivability of E. coli. Although computational simulations have been used to explore the potential functionality of FFLs, a comprehensive study of the functions of all structural types based on in vivo data is lacking. Also, the regulatory role of CRP-mediated feed-forward loops (CRP-FFLs) remain unclear to date. Using EcoCyc and RegulonDB, we identified 393 CRP-FFLs in the E. coli. Dose-response genomic microarray of E. coli revealed dynamic gene expression of each target gene of CRP-FFLs in response to a range of cAMP dosages. All eight types of FFLs were present in CRP regulon with various expression patterns of each CRP-FFL, that were further divided into five functional groups. Microarray and reported regulatory relationships identified 202 CRP-FFLs which were directly regulated by CRP in these eight types of FFLs. Interestingly, 30% (147/482) of genes were directly regulated by CRP and CRP-regulated TFs, indicating that these CRP-regulated genes were also regulated by other CRP-regulated TFs responding to environmental signals through CRP-FFLs. Furthermore, we applied gene ontology annotation to reveal the biological functions of CRP-FFLs.
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Life Sciences, Molecular Biology; long noncoding RNA; MALAT1; UCA1; NRON; Z probe; colorectal cancer; pancreatic cancer; breast cancer
Online: 6 June 2018 (13:05:30 CEST)
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Formalin-Fixed Paraffin Embedded (FFPE) tissues are a valuable resource in studying different markers and mechanistic molecules (protein, DNA and RNA) in order to understand the etiology of different cancers as well as many other diseases. Degradation and modification of RNA is the major challenge in utilizing FFPE tissue samples in medical research. Recently, non-protein coding transcripts long non-coding RNAs (lncRNAs), have gained significant attention due to their important biological actions and potential involvement in cancer. There is no validated method except qRTPCR or RNAseq to evaluate and study lncRNA expression. We have standardized and are reporting a sensitive Z probe based in situ hybridization method to identify, localize and quantitate lncRNA in FFPE tissues. This assay is sensitive to single transcript and localizes lncRNA in individual cells within tumor. We have characterized a tumor suppressor lncRNA-NRON (non coding repressor of NFAT), which is scarcely expressed, a moderately expressed oncogeneic lncRNA UCA1 (urothelial cancer associated 1), and a highly studied and expressed lncRNA MALAT1 (metastasis associated lung adenocarcinoma transcript1) in different cancers. High MALAT1 staining was found in colorectal, breast and pancreatic cancer. MALAT1 expression increased with the progression of the stage in colorectal cancer and invasiveness in breast cancer.
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Life Sciences, Molecular Biology; abies beshanzuensis; ITS variation; structure; molecular phylogeny
Online: 24 May 2018 (10:40:55 CEST)
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Abies beshanzuensis, an extremely endangered species, attracts serious concerns on genetic diversity recovery and population protection. However, little genetic information was known about it till now. In this study, intra-/intergenomic ITS variation, secondary structure, and molecular phylogeny of A.beshanzuensis were determined by nrDNA-ITS marker, and results indicated that, ITS region featured rich polymorphism in ITS1 and highly conservative in 5.8S/ITS2 among intra-/inter-genome, implying rich genetic diversities and the occurrence of non-concerted evolution in ITS region. Predicated 5.8S structure possessed Helices-Loops with 3 motifs (M1/M2/M3) and 5 helices B4-B8, and ITS2 could form conservative Clover-like structure with 5 ribotypes, manifesting genetically structural generalities and individualities. Thirteen ITS pseudogenes were also identified from 76 samples (or clones). Molecular phylogeny revealed that, A.beshanzuensis shared genetically closer relationships with A.fanjingshanensis, A.chensiensis, A.yuanbaoshanensis among genus Abies. The available original data provided rich genetic information on ITS sequence, structure and molecular phylogeny of A.beshanzuensis, which not only updated the databases of ITS sequences as well as secondary structures essential for phylogenetic reference and DNA barcoding analyses, but also contributed to deep exploration of population diversities, origin and evolution as well theoretical direction for population recovery and protection of A.beshanzuensis.
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Life Sciences, Molecular Biology; fibrillin; cucumber; genome-wide; gene expression; high light stress
Online: 24 May 2018 (05:24:00 CEST)
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Fibrillin (FBN) is a plastid lipid-associated protein found in photosynthetic organisms from cyanobacteria to plants. In this study, 10 CsaFBN genes were identified in genomic DNA sequences of cucumber (Chinese long and Gy14) through database searches using the conserved domain of FBN and the 14 FBN genes of Arabidopsis. Phylogenetic analysis of CsaFBN protein sequences showed that there was no counterpart of Arabidopsis and rice FBN5 in the cucumber genome. FBN5 is essential for growth in Arabidopsis and rice; its absence in cucumber may be because of incomplete genome sequences or that another FBN carries out its functions. Among the 10 CsaFBN genes, CsaFBN1 and CsaFBN9 were the most divergent in terms of nucleotide sequences. Most of the CsaFBN genes were expressed in the leaf, stem, and fruit. CsaFBN4 showed the highest mRNA expression levels in various tissues, followed by CsaFBN6, CsaFBN1, and CsaFBN9. High-light stress combined with low temperature decreased photosynthetic efficiency and highly induced transcript levels of CsaFBN1, CsaFBN6, and CsaFBN11, which decreased after 24 h treatment. Transcript levels of the other seven genes were changed only slightly. This result suggests that CsaFBN1, CsaFBN6, and CsaFBN11 may be involved in photoprotection under high-light conditions at low temperature.
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Life Sciences, Molecular Biology; Vezf1; angiogenesis; vascular biology; endothelial cells; MSS31, tube formation, small molecule inhibitors computational modeling.
Online: 15 May 2018 (08:08:15 CEST)
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Discovery of inhibitors for endothelial-related transcription factors can contribute to the development of angiogenic therapies that treat diseases ranging from cardiovascular to cancer. The role of transcription factor Vezf1 in vascular development and regulation of angiogenesis has been defined by several earlier studies. Through construction of a computational model for Vezf1, work here has identified a novel small molecule drug capable of inhibiting Vezf1 from binding to its cognate DNA binding site. Using structure-based design and virtual screening of the NCI Diversity Compound Library, 12 shortlisted compounds were tested for their ability to interfere with the binding of Vezf1 to DNA using electrophoretic gel mobility shift assays. We identified one compound, T4, which has an IC50 of 20uM. Using murine endothelial cells, MSS31, we tested the effect of T4 on endothelial cell viability and angiogenesis by using tube formation assay. Our data show that addition of T4 in cell culture medium does not affect cell viability at concentrations lower or equal to its IC 50 but strongly inhibits the network formation by MSS31 in the tube formation assays. Given its potential efficacy, this inhibitor has significant therapeutic potential in several human diseases raging from wound healing to cancer.
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Life Sciences, Molecular Biology; citrus breeding; diversity; genetic similarity; Lime; molecular markers; PCR
Online: 9 May 2018 (11:05:37 CEST)
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Acid lime [Citrus aurantifolia (Christm.) Swingle] is a fruit crop, enriched with high commercial value and is cultivated in 60 out of 75 districts representing all geographical landscapes of Nepal. Lack of high yielding cultivars is probably one of the main reason for its extremely reduced productivity which warrants a deep understanding of genetic diversity in existing germplasm. Hereby, we aim to access the genetic diversity of acid lime germplasm cultivated at 3-different ecological gradients of eastern Nepal employing PCR-based Inter-Simple Sequence Repeats markers (ISSR). Altogether, 21 polymorphic ISSR markers were used to assess the genetic diversity in 60 acid lime cultivars sampled from different geographical locations. Analysis of binary data matrix was performed on the basis of bands obtained, scoring of the data was done accordingly, and principal coordinate analysis and phenogram were constructed using different computer algorithms. ISSR profiling yielded 234 amplicons, of which 87.18% were found to be polymorphic. The number of amplified fragments ranged from 7-18 with amplicon size ranging from 250-3200 bp. The NTSYS based Cluster analysis using UPGMA algorithm taking Dice Similarity coefficient separated 60 accessions into 2-major and 3-minor clusters. The genetic diversity analysis revealed the highest for Terai and the lowest for High-hill zone. Cluster I comprised of accessions from High-hill and Mid-hill regions revealing the close genetic relationship, whereas cluster II comprised of accessions from all three agro-ecological zones and the exotic varieties. Furthermore, our results revealed the accessions harvested from different geographical gradients were not genetically distinct, but highest diversity was observed in Terai accessions in comparison to the regions belonging to the High and Mid-hills. Thus, our data indicate that the ISSR provides a better option for evaluating the genetic diversity of Nepalese Acid Lime cultivars and furnished significant information, assisting parental selection in current and future breeding programs and germplasm conservation which ultimately may help to provide a technological breakthrough for the farmers of the developing country like Nepal.
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Life Sciences, Molecular Biology; Fusarium head blight; deoxynivalenol; cytotoxicity; Caenorhabditis elegans; RNAseq
Online: 29 April 2018 (10:40:16 CEST)
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Deoxynivalenol (DON) is a mycotoxin produced by Fusarium spp. that causes Fusarium head blight (FHB) disease in cereal crops. Ingestion of food contaminated with DON poses serious human health complications. However, the DON cytotoxicity has been mostly deduced from animal studies. In this study, we used the nematode Caenorhabditis elegans (C. elegans) as a tractable animal model to dissect the toxic effect of DON. Our results indicate that DON reduces the fecundity and lifespan of C. elegans. The real-time RT-PCR analysis showed that DON upregulates innate immunity-related genes including C17H12.8 and K08D8.5 encoding PMK-1 (mitogen activated protein kinase-1)-regulated immune effectors, and F35E12.5 encoding a CUB-like domain-containing protein. Furthermore, our RNAseq data demonstrate that out of ~ 17,000 C. elegans genes, 313 are upregulated and 166 were downregulated by DON treatment. Among the DON-upregulated genes, several are ugt genes encoding UDP-glucuronosyl transferase (UGTs) which are known to be involved in chemical detoxification. The three upregulated genes, F52F10.4 (oac-32), C10H11.6 (ugt-26) and C10H11.4 (ugt-28) encoding the O-acyltransferase homolog, UGT26 and UGT 28, respectively, are shown to contribute to DON tolerance by RNAi bacterial feeding experiment. The results of this study provide insights to the targets of DON cytotoxicity and potential mitigation measures.
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Life Sciences, Molecular Biology; myocardial infarction; heart attack; gene set enrichment analysis; protein-protein interaction network; bioinformatics; systems biology; in silico study
Online: 26 April 2018 (10:22:31 CEST)
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Myocardial infarction, more commonly known as heart attack, is a huge health problem around the world. It is a result of inadequate blood supply to certain parts of the heart and death of heart muscle cells in that region. Although it has been around for a long time, newer and newer ways of probing myocardial infarction is being followed. Bioinformatics and Systems Biology are relatively recent fields to try to give new insights into myocardial infarction. Following the footsteps of others, this in silico study has tried to chime in on the investigation into myocardial infarction. The study began with the gene expression omnibus dataset uploaded to the NCBI from a whole-genome gene expression analysis carried out at Mayo Clinic in Rochester, Minnesota. From the dataset, differentially expressed genes following first-time myocardial infarction were identified and classified into up-regulated and down-regulated ones. Gene Set Enrichment Analysis (GSEA) was carried out on the up-regulated genes which were statistically significant and corresponded with the NCBI generated annotations. Protein-Protein Interaction Network for these genes was constructed. GSEA revealed 5 transcription factors, 5 microRNAs and 3 pathways significantly associated with them. From the Protein-Protein Interaction Network, 6 key proteins (hub nodes) have been identified. These 6 proteins may open a new window of opportunity for the discovery/design of new drugs for mitigating the damage caused by myocardial infarction.
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Life Sciences, Molecular Biology; Alzheimer’s disease (AD); amyloid precursor protein (APP); familial AD (FAD); sporadic AD (SAD); BACE1 inhibitors; APP-independent generation of beta amyloid
Online: 6 April 2018 (15:16:08 CEST)
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The present article analyzes the results of recent clinical trials of beta secretase inhibition in sporadic Alzheimer’ disease (SAD), considers the striking dichotomy between successes in tests of BACE1 inhibitors in healthy subjects and familial AD (FAD) models versus persistent failures of clinical trials and interprets it as a confirmation of key predictions for a mechanism of APP-independent, beta secretase inhibition-resistant production of beta amyloid in SAD, previously proposed by us. In the light of this concept, FAD and SAD should be regarded as distinctly different diseases as far as beta-amyloid generation mechanisms are concerned, and whereas beta secretase inhibition would be neither applicable nor effective in treatment of SAD, the BACE1 inhibitor(s) deemed failed in SAD trials could be perfectly suitable for treatment of FAD. Moreover, targeting the aspects of AD other than cleavages of the APP by beta and alpha secretases should have analogous impacts in both FAD and SAD.
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Life Sciences, Molecular Biology; CREBH; SREBP; LXRα; PPARα; lipid metabolism; transcription; FGF21
Online: 28 March 2018 (08:06:15 CEST)
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The cyclic AMP-responsive element-binding protein H (CREBH, encoded by CREB3L3) is a membrane-bound transcriptional factor that primarily localizes in the liver and small intestine. CREBH governs triglyceride metabolism in the liver, which mediates the changes in gene expression governing fatty acid oxidation, ketogenesis, and apolipoproteins upregulating LPL activity. A deficiency of CREBH in mice leads to severe hypertriglyceridemia. CREBH, in synergy with PPARα, has a crucial role in upregulating Fgf21 expression, which is implicated in metabolic homeostasis. CREBH binds to and functions as a co-activator for both PPARα and LXRα in regulating gene expression of lipid metabolism. Furthermore, intestinal CREBH in overexpression reduces cholesterol absorption and suppresses high-cholesterol diet-induced fatty liver. Conversely, a deficiency of CrebH in mice fed on various high-fat diets leads to severe fatty liver. Thus, CREBH could be a therapeutic target in the treatment of metabolic diseases.
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Life Sciences, Molecular Biology; hypoxia; chromatin; transcriptional repression; repressor complexes; JmjC; histone methylation; HIF
Online: 1 March 2018 (06:36:57 CET)
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Hypoxia, or reduced oxygen availability, has been studied extensively for its ability to activate specific genes. Hypoxia induced gene expression is mediated by the HIF transcription factors, although not exclusively so. Despite the great knowledge on the mechanisms by which hypoxia activates genes, much less is known about how hypoxia promotes gene repression. In this review, we discuss the potential mechanisms underlying hypoxia-induced transcriptional repression responses. We highlight HIF-dependent and independent mechanisms, but also the potential roles of dioxygenases with functions at the nucleosome and DNA level. Finally, we discuss recent evidence regarding the involvement of transcriptional repressor complexes in hypoxia.
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Life Sciences, Molecular Biology; ark shell; transcriptome; growth; metabolism; differentially expressed genes
Online: 1 March 2018 (04:47:45 CET)
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To understand the molecular mechanism associated with growth variability in bivalves, the Solexa/Illumina technology was employed to analyze the transcriptomic profiles of extreme growth rate differences (fast- VS. slow-growing individuals) in one full-sib family of the ark shell Scapharca subcrenata. De novo assembly of S. subcrenata transcriptome yielded 276,082,016 raw reads, which were assembled into 98,502 unique transcripts by Trinity strategy. A total of 6,357 differentially expressed genes (DEGs) were obtained between fast- and slow-growing individuals, with 580 up-regulated expression and 5777 down-regulated expression. Functional annotation revealed that the largest proportion of DEGs were classified to the large or small subunit ribosomal protein, all of which showed significantly lower expression levels in fast-growing group than those in slow-growing group. GO enrichment analysis identified the maximum of DEGs to biological process, followed by molecular function and cellular component. Most of the top enriched KEGG pathways were related to energy metabolism, protein synthesis and degradation. These findings reveal the link between gene expression and contrasting phenotypes in ark shells, which support that fast-growing individuals may be resulted from decreased energy requirements for metabolism maintenance, accompanying with greater efficiency of protein synthesis and degradation in bivalves.
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Life Sciences, Molecular Biology; spermine; cyclooctaoxygen; DNA; selenium; glyphosate; AMPA
Online: 4 December 2017 (13:03:14 CET)
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Oxygen exists in two gaseous and six solid allotropic modifications. An additional allotropic modification of oxygen, the cyclooctaoxygen, was predicted to exist in 1990. The first synthesis and characterization of cyclooctaoxygen as its sodium crown complex, isolated in the form of three cytosine nucleoside hydrochloride complexes, was reported in 2016. Cyclooctaoxygen sodium was synthesized from atmospheric oxygen, or catalase effect-generated oxygen, under catalysis of cytosine nucleosides and either ninhydrin or eukaryotic low-molecular weight RNA. The cationic cyclooctaoxygen sodium complex was shown to bind RNA and DNA, to associate with single-stranded DNA and spermine phosphate, and to be essentially non-toxic to cultured mammalian cells at 0.1–1.0 mM concentration. We postulated that cyclooctaoxygen is formed in most eukaryotic cells from dihydrogen peroxide in a catalase reaction catalysed by cytidine and RNA. A molecular biological model was deduced for a first epigenetic shell of eukaryotic euchromatin. This model incorporates an epigenetic explanation for the interactions of the essential micronutrient selenium (as selenite) with eukaryotic euchromatin. The sperminium phosphate/cyclooctaoxygen sodium complex is calculated to cover the actively transcribed regions (2.6%) of bovine lymphocyte interphase genome. Cyclooctaoxygen seems to be naturally absent in hypoxia-induced highly condensed chromatin, taken as a model for eukaryotic metaphase/anaphase/early telophase mitotic chromatin. We hence propose that the cyclooctaoxygen sodium-bridged spermine phosphate and selenite coverage serves as an epigenetic shell of actively transcribed gene regions in eukaryotic ‘open’ euchromatin DNA. The total herbicide glyphosate (ROUNDUP) and its metabolite (aminomethyl)phosphonic acid (AMPA) are proved to represent ‘epigenetic poisons’, since they both selectively destroy the cyclooctaoxygen sodium complex. This definition is of reason, since the destruction of cyclooctaoxygen is sufficient to bring the protection shield of human euchromatin into collateral epigenetic collapse.
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Kai-Wen Hsu,
Chien-Yu Huang,
Ka-Wai Tam,
Chun-Yu Lin,
Li-Chi Huang,
Ching-Ling Lin,
Wen-Shyang Hsieh,
Wei-Ming Chi,
Yu-Jia Chang,
Po-Li Wei,
Chia-Hwa Lee
Life Sciences, Molecular Biology; non-invasive apoptosis detection sensor; breast cancer; HDACi
Online: 1 December 2017 (12:08:13 CET)
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Breast cancer is the most common malignancies in women and the second leading cause of cancer death in women. Triple negative breast cancer (TNBC) subtype is a breast cancer subset without ER, PR and HER2 expression, limiting treatment options and presenting a poorer survival rate. Thus, we investigated whether HDACi would be used as potential anti-cancer therapy on breast cancer cells. In this study, we found TNBC and HER2-enrich breast cancers are extremely sensitive to Panobinostat, Belinostat of HDACi via experiments of cell viability assay, apoptotic marker identification and flow cytometry measurement. On the other hand, we developed a bioluminescence based live cell non-invasive apoptosis detection sensor (IADS) detection system to evaluate the quantitative and kinetic analyses of apoptotic cell death by HDAC treatment on breast cancer cells. In addition, the use of HDACi may also be accompanied with chemotherapeutic agent such as doxorubicin to synergic drug sensitivity on TNBC cell (MDA-MB-231), but not in breast normal epithelia cells (MCF-10A), providing therapeutic benefits against breast tumor in clinic.
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Life Sciences, Molecular Biology; mitochondria; proteolysis; protein half-life; ubiquitin
Online: 27 November 2017 (09:18:27 CET)
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The mitochondrial network is a dynamic organization within eukaryotic cells that participates in a variety of essential cellular processes, such as ATP synthesis, central metabolism, apoptosis and inflammation. The mitochondrial network is balanced between rates of fusion and fission that respond to pathophysiologic signals to coordinate appropriate mitochondrial processes. Mitochondrial fusion and fission are regulated by proteins that either reside or translocate to the inner or outer mitochondrial membranes or are soluble in the inter-membrane space. Mitochondrial fission and fusion are performed by GTPases on the outer and inner mitochondrial membranes with the assistance of other mitochondrial proteins. Due to the essential nature of mitochondrial function for cellular homeostasis regulation of mitochondrial dynamics is under strict control. Some of the mechanisms used to regulate the function of these proteins are post-translational proteolysis and/or turnover and this review will discuss these mechanisms required for correct mitochondrial network organization.
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Life Sciences, Molecular Biology; posttranscriptional regulation; Saccharomyces cerevisiae; nonsense mediated decay; NMD; splicing; 4-thiouracil; 4sU; rpb1-1; exponential decay
Online: 9 November 2017 (03:24:17 CET)
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The turnover of the RNA molecules is determined by the rates of transcription and RNA degradation. Several methods have been developed to study mRNA turnover since the beginnings of molecular biology. Here we summarize the main methods to measure RNA half-life: transcription inhibition, gene control and metabolic labelling. These methods were used to detect the cellular activity of the mRNAs degradation machinery, including the exo-ribonuclease Xrn1 and the exosome. Less progress has been made in the study of the differential stability of mature RNAs because the different methods have often yielded inconsistent results so that an mRNA considered to be stable can be classified as unstable by another method. Recent advances in the systematic comparison of different method variants in yeast have permitted the identification of the least invasive methodologies that reflect half-lives the most faithfully, which is expected to open the way for a consistent quantitative analysis of the determinants of mRNA stability.
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Life Sciences, Molecular Biology; Bioinformatics; Ionizing radiation; Microarrays; Radiation-induced bystander effects; Transcriptomics
Online: 6 November 2017 (15:02:00 CET)
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Ionizing radiation-induced bystander effects (RIBE) encompass a number of effects with potential for a plethora of damages in adjacent non-irradiated tissue. The cascade of molecular events is initiated in response to the exposure to ionizing radiation (IR), something that may occur during diagnostic or therapeutic medical applications. In order to better investigate these complex response mechanisms, we employed a unified framework integrating statistical microarray analysis, signal normalization and translational bioinformatics functional analysis techniques. This approach was applied to several microarray datasets from Gene Expression Omnibus (GEO) related to RIBE. The analysis produced lists of differentially expressed genes, contrasting bystander and irradiated samples versus sham-irradiated controls. Furthermore, comparative molecular analysis through BioInfoMiner, which integrates advanced statistical enrichment and prioritization methodologies, revealed discrete biological processes, at the cellular level. For example, negative regulation of growth, cellular response to Zn2+- Cd2+, Wnt and NIK/NF-kappaB signalling, which refine the description of the phenotypic landscape of RIBE. Our results provide a more solid understanding of RIBE cell-specific response patterns, especially in the case of high-LET radiations like α-particles and carbon-ions.
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Life Sciences, Molecular Biology; WNT pathway; porcupine inhibitor ETC-1922159; sensitivity analysis; colorectal cancer; unknown biological hypotheses; combinatorial search space; support vector ranking; DNA repair and genomic stability factor RAD51
Online: 1 November 2017 (05:08:04 CET)
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DNA repair helps in maintaining the proper and healthy functioning for the cells in the human body. Failure in DNA repair process can lead to aberrations as well as tumorous stages. There are various types of damages that a DNA can go through, one of which is the DNA double strand breaks (DSB) that can be repaired via homologous recombination (HR). RAD51 plays a central role in HR and has been implicated as a negative/poor prognostic marker for colorectal adenocarcinoma, with high expression in colorectal cancer. Mechanistically, RAD51AP1 facilitates RAD51 during the repairing process by binding with RAD51 via two DNA binding sites, thus helping in the D-loop formation in the HR process. Often, in biology, we are faced with the problem of exploring relevant unknown biological hypotheses in the form of myriads of combination of factors that might be affecting the pathway under certain conditions. For example, RAD51AP1-XRCC2 is one such 2nd order combination whose relation needs to be tested under the influence recently developed Porcupine-WNT inhibitor ETC-1922159. The x-ray repair cross complementing XRCC family is known to work as a mediator or stabilizer for RAD51 during the HR process. The inhibitor is known to suppress Porcupine and thus inhibit a range of oncogenes known to be directly or indirectly affected by the Wnts. In a recent unpublished work in bioRxiv, we had the opportunity to rank these unknown biological hypotheses for down regulated genes at 2nd order level after the drug was administered. The in silico observations showed that the combination of RAD51AP1-XRCC2 was assigned a relatively lower rank, thus validating the pipeline's efficacy with the confirmed wet lab experiment that indicate that both RAD51AP1 and XRCC2 were down regulated after treatment in cancer cells. Here, we take one step further by in silico analysis of the 3rd order combinations of RAD51-X-X & RAD51AP1-X-X (X can be known or unknown factor), from a range of 100 randomly picked down regulated genes after ETC-1922159 treatment. The pipeline uses the density based HSIC (Hibert Schmidth Information Criterion) sensitivity index with an rbf (radial basis function) kernel, which is known to be highly effective in sensitivity analysis. Various unknown/unexplored/untested RAD51/RAD51AP1 related 3rd order biological hypotheses emerge some of which are confirmed in wet lab, while others need to be tested.
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Life Sciences, Molecular Biology; Tree of Life; origins of species; cellular lineage escape; endogenous compartmentation; proto-organelles; eukaryogenesis; origins of sex; syntrophic biofilms; endosymbiosis
Online: 24 October 2017 (04:27:17 CEST)
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This article reevaluates the Woesean concept of crossing a ‘Darwinian threshold’ from pre-genomic communality, as prevailing in an ancestral ‘progenote’ state, to vertically stable lineages of autonomous and self-similar cells. This transition from collective trunk-line evolution to Darwinian speciation is dependent on the generation of modular organismal genomes. The same general principle should be valid at subcellular levels, allowing the emergence of semi-autonomous genomic agents, such as viruses and plasmid-carrying endogenous vesicles with organelle-like properties. As compartmentalized agents of endogenous nature could start with smaller genomes than those required for fully autonomous cells, it is conjectured that stable subcellular lineages emerged earlier than their cellular counterparts. Referring to the recent ‘pre-endosymbiont hypothesis’, it is proposed that free-living bacteria (the first ‘prokaryote’ cells) arose by ‘lineage escape’ from plasmid-bearing organelle-like compartments, evolving inside the internally complexifying ‘paracells’ of the progenote community. The double-membrane envelopes of diderm bacteria may have resulted from cell-biological processes facilitating cellular lineage escape. The later emergence of archaeal cells (resembling bacteria in ‘prokaryote’ appearance with unichromosomal genomes) and eukaryotic organisms (with compartmented cells and multichromosal genomes) can also be interpreted in terms of this modified progenote hypothesis. Conceivably, the multichromosomal genomes of eukaryotes were bundled in endogenous nuclear compartments to organize a ‘nuclear-cytoplasmic lineage’, which became vertically stable by perfecting mitosis/meiosis-like divisions and yet retained some intra-species population confluence by sexual division-fusion cycles.
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Life Sciences, Molecular Biology; WNT pathway; porcupine inhibitor ETC-1922159; sensitivity analysis; colorectal cancer; unknown biological hypotheses; combinatorial search space; support vector ranking
Online: 18 October 2017 (05:58:17 CEST)
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WNT10B belongs to the family of WNT proteins that are implicated in a range of phenomena that are affected by the Wnt signaling pathway. Recent studies have shown that WNT10B plays a role in colorectal cancer. WNTs have been found to directly affect the stemness of the tumor cells via regulation of ASCL2. Switching off the ASCL2 literally blocks the stemness process of the tumor cells and vice versa. Furthermore, recent findings suggest BVES to be highly suppressed in malignancies and in vitro deletions of BVES show higher Wnt signaling activity to induce stem- ness. WNT10B was found to be highly expressed in such cases. Often, in biology, we are faced with the problem of exploring relevant unknown biological hypotheses in the form of myriads of combination of factors that might be affecting the pathway under certain conditions. For example, WNT10B-ASCL2 is one such 2nd order combination whose relation needs to be tested under the influence of recently developed porcupine-WNT inhibitor ETC-1922159. The inhibitor is known to suppress PORCN (porcupine) and thus inhibit a range of oncogenes known to be directly or indirectly affected by the Wnts. In a recent unpublished work in bioRxiv, Sinha 1, we had the opportunity to rank these unknown biological hypotheses for down regulated genes at 2nd order level after the drug was administered. The in silico observations showed that the combination of WNT10B-ASCL2 was assigned a relatively lower rank, thus validating the pipeline’s efficacy with the confirmed wet lab experiment that indicate that both WNT10B and ASCL2 were down regulated after treatment in cancer cells. Here, we take one step further by in silico analysis of the 3rd order combinations of WNT10B-X-X (X can be known or unknown factor), from a range of 100 randomly picked down regulated genes after ETC-1922159 treatment. The pipeline uses the density based HSIC (Hilbert Schmidt Information Criterion) sensitivity index with an rbf (ra- dial basis function) kernel, which is known to be highly effective in sensitivity analysis. Various unknown/unexplored/untested 3rd order biological hypotheses emerge some of which are con- firmed in wet lab, while others need to be tested. The potential of such ranking is indispensable in the current era of search in a vast combinatorial forest.
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Life Sciences, Molecular Biology; lentinula edodes; Lp16-PSP; acute promyeloid leukemia; extrinsic and lntrinsic apoptotic pathway; G1 phase cell cycle arrest
Online: 25 September 2017 (08:53:12 CEST)
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Lp16-PSP from Lentinula edodes strain C91-3 has been reported previously in our laboratory to have selective cytotoxic activity against a panel of human cell lines. Herein, we have used several parameters in order to characterize the Lp16-PSP-induced cell death using HL-60 as model cancer. The results of phase contrast microscopy, nuclear examination, DNA fragmentation detection and flow cytometry revealed that high doses of Lp16-PSP resulted in the induction of apoptosis in HL-60 cells. The colorimetric assay showed the activation of caspase-8, -9 and -3 cascade highlighting the involvement of Fas/FasL-related pathway. Whereas, western blot revealed the cleavage of caspase-3, increased expression of Bax, the release of cytochrome c and decreased expression of Bcl-2 in a dose-dependent manner, suggesting the intrinsic pathway might be involved in Lp16-PSP-induced apoptosis either. Low doses of Lp16-PSP resulted in the anchorage-independent growth inhibition, induction of G1 phase arrest accompanied by the increased expression of p21WAF1/CIP1 along with the decreased expression of cyclin D, E, and cdk6. Our findings suggest that induction of apoptosis and p21WAF1/CIP1 mediated G1 arrest might be one of the mechanisms of the action of Lp16-PSP, however, further investigations on multiple leukemia cell lines and in vivo models are of ultimate need.
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Life Sciences, Molecular Biology; ischemia-reperfusion injury (IRI), ω3-PUFA, AMP-activated protein kinase (AMPK), autophagy
Online: 4 August 2017 (12:56:08 CEST)
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Regulated autophagy is involved in the repair of renal ischemia-reperfusion injury (IRI). ω3-Polyunsaturated fatty acids (ω3-PUFAs) show protective effects against various renal injuries. It was recently reported that ω3-PUFAs regulate autophagy. We assessed whether ω3-PUFAs attenuated IR-induced acute kidney injury (AKI) and evaluated associated mechanisms. C57Bl/6 background fat-1 mice and wild-type mice (wt) were divided into four groups: wt sham (n = 10), fat-1 sham (n = 10), wt IRI (reperfusion 35 min after clamping both the renal artery and vein; n = 15), and fat-1 IRI (n = 15). Kidneys and blood were harvested 24 h after IRI. Renal histological and molecular data were collected. The kidneys of fat-1 mice showed better renal cell survival, renal function, and pathological damage than those of wt mice after IRI. In addition, fat-1 mice showed less oxidative stress and autophagy impairment; greater amounts of LC3, Beclin-1, and Atg7; lower amounts of p62; and higher levels of renal cathepsin D and ATP6E than wt kidneys. They also showed more AMPK activation, which resulted in the inhibition of phosphorylation of the mammalian target of rapamycin (mTOR). Collectively, ω3-PUFAs in fat-1 mice contributed to AMPK mediated autophagy activation, leading to a renoprotective response.
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Life Sciences, Molecular Biology; Rifampicin; insertion; biological cost; M. tuberculosis; resistance; structural bioinformatics
Online: 27 July 2017 (11:07:55 CEST)
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Rifampicin is one of the most important chemotherapeutic agents used in the treatment of tuberculosis. M. tuberculosis clinical strains resistant to rifampicin harbor mainly mutation in an 81-base pair region of rpoB. These mutations mainly consist of single amino acid substitutions. However insertions also can be related with rifampicin resistance strains. Herein, we described an insertion of 12 nucleotides in clinical isolates of M. tuberculosis resistant to rifampicin, all obtained from inmates. To evaluate the importance this insertion in surviving and drug resistance, it were carried out fitness experimental assays as well as in silico studies of 3D structural models, molecular docking simulations and virtual screening. The medical records of the seven patients showed all were previously treated to tuberculosis. Growth curves shown that the insertion determines a biological cost when compared to wild type rpoB and katG; or the double mutated rpoB S531L and katG S315T. From docking and molecular dynamics simulations it can be inferred that the insertion does not affect the process of synthesis of RNA transcripts. On the other hand, in the mutant RNAP-RIF complex rifampicin confirmed a low affinity interaction for the mutant form. Interesting, virtual screening for potential inhibitors for wtRNAP and mRNAP using a library of 1446 compounds approved by the FDA showed that the best ligands were mainly compounds with antibiotic activity, although the targets involved in the pharmacological action are other than RNAP. In conclusion, seven strains of M. tuberculosis RIF resistant that present an insertion of four amino acids in RNA polymerase showed by growth curve assays, a biological cost. Further, bioinformatics tools had characterized the putative drug resistance dynamic as well as the maintenance of RNA polymerase activity.
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Life Sciences, Molecular Biology; TGF-β; gastric cancer; microenvironment
Online: 14 July 2017 (11:59:25 CEST)
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Gastric cancer is an intractable disease with a high incidence of peritoneal dissemination and obstructive symptoms (e.g. ileus, jaundice, and hydronephrosis) arising from accompanying marked fibrosis. Microenvironmental interactions between cancer cells and stromal cells are the suggested cause of the disease. Transforming growth factor (TGF-β) is an intriguing cytokine exhibiting dual roles in malignant disease, acting as an important mediator of cancer invasion, metastasis, and angiogenesis as well as exhibiting antitumor functions. Moreover, the TGF-β pathway contributes to the generation of a favorable microenvironment for tumor growth and metastasis throughout the steps of carcinogenesis. Among these effects, TGF-β induces the epithelial-to-mesenchymal transition with prometastatic functions, contributes to the conversion of stromal cells to carcinoma-associated fibroblasts, and suppresses the function of immune cells, which compromises the antitumor immune response, leading to cancer progression and stromal fibrosis. In this review, we address the role of the essential TGF-β signaling pathway in the regulation of the activities of components of the tumor microenvironment of gastric cancer and how this contributes to tumor progression and stromal fibrosis. We then explore the potential to optimize therapy that inhibits TGF-β signaling in the preclinical and clinical settings of gastric cancer.
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Life Sciences, Molecular Biology; Specnvezhenide; osteoarthritis; chondrocyte; NF-κB; wnt/β-catenin
Online: 16 June 2017 (04:20:07 CEST)
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As a chronic disease, osteoarthritis (OA) leads to degradation of both cartilage and subchondral bone, of which the development is related to proinflammatory cytokines like interleukin-1β. In the present study, the anti-inflammatory effect of Specnvezhenide in osteoarthritis and mechanism of it was studied in vitro and in vivo. The results showed that Specnvezhenide decreases interleukin-1β-induced expression of matix-degrading enzymes and reduces the activation of NF-κB and wnt/β-catenin pathways in vitro. Furthermore, Specnvezhenide treatment prevents the degeneration of both cartilage and subchondral bone in rats OA model. As conclusion, to the best of our knowledge, we report firstly that Specnvezhenide decreases interleukin-1β-induced inflammation on rat chondrocytes by inhibiting activation of NF-κB and wnt/β-catenin pathways, and has therapeutic potential in OA treatment.
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Life Sciences, Molecular Biology; gibberellin; photoperiod; mutant; floral induction; flowering time
Online: 2 June 2017 (07:45:32 CEST)
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Flower bud formation and flowering in chrysanthemum occur under short day conditions (SD), but the molecular basis for the switch to reproductive growth is less well understood than in model plants. Here, a spontaneous mutant able to flower under long days is described. In an attempt to reveal the pathway(s) involved in the formation of flower buds under contrasting daylengths, transcriptome sequencing was carried out in plants grown both under SD and under long day conditions (LD). A number of differentially transcribed genes involved in the various known flowering pathways were identified. Both circadian clock genes and CmFTL3 were up-regulated under SD, thereby inducing floral bud formation and flowering. The gibberellin (GA) signalling pathway-related genes GA20ox and GID1 were up-regulated in the mutant under LD, while the catabolic gene GA2ox and GAI was down-regulated, thereby inducing the transcription of CmFTL1, SOC1 and LFY. The GA content of the leaf was higher in the mutant than in the wild type under LD. When treated with GA, the mutant flowered earlier under both SD and LD, but there was no other detectable phenotype difference between the two lines. The indication was that the photoperiod pathway majorly regulates flower bud formation and flowering time in chrysanthemum under SD. GA signalling pathway only plays a subsidiary role for flowering. However, the GA signalling pathway predominated for flowering under LD.
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Life Sciences, Molecular Biology; ABCC transporter; lateral roots; Triticum aestivum; auxin; transport inhibition
Online: 8 May 2017 (07:48:20 CEST)
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TaABCC13 is member of wheat ABCC subclass of transporters. The RNAi mediated silencing of this transporter in wheat results in lowering of seed phytic acid level and other developmental defects. In addition to that, wheat ABCC13 was involved in cadmium detoxification as evident by the complementation assays in yeast. The appearance of early lateral roots in these transgenic seedlings speculated the possibility for studying the role of localized auxin-mediated effects. In the current study, firstly, the expression of auxin related genes was studied in the transgenic roots. Enhanced expression of genes pertaining to either auxin biosynthesis or its transport was observed in transgenic wheat seedling roots suggesting the direct effect of the hormone. Further, the early emergence of lateral roots in transgenic wheat seedlings was affected due to the presence of auxin-transport inhibitor suggesting the direct effect of hormones in root development. In conclusion, herein we provide the novel evidence for the auxin mediated regulation of lateral root emergence in TaABCC13:RNAi seedlings.
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Life Sciences, Molecular Biology; fusion proteins; protein therapeutics; ricin; pokeweed antiviral protein; protein engineering; immunotoxins; ribosome-inactivating proteins.
Online: 1 May 2017 (10:51:21 CEST)
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Fusion protein therapeutics engineering is advancing to meet the need for novel medicine. Herein, we further characterize the development of novel RTA & PAP-S1 antiviral fusion proteins. In brief, RTA/PAP-S1 and PAP-S1/RTA fusion proteins were produced in both cell free and E. coli in vivo expression systems, purified by His-tag affinity chromatography, and protein synthesis inhibitory activity assayed by comparison to the production of a control protein, CalmL3. Results showed that the RTA/PAP-S1 fusion protein is amenable to standardized production and purification and has both increased potency and less toxicity compared to either RTA or PAP-S1 alone. Thus, this research highlights the developmental potential of novel fusion proteins with reduced cytotoxic risk and increased potency.
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Life Sciences, Molecular Biology; water bridging; dipole waves; coherent states; polymerase chain reaction; DNA amplification; DNA transduction; enzyme catalytic activity; fractal-like self-similarity
Online: 25 April 2017 (04:24:21 CEST)
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We discuss the role of water bridging the DNA-enzyme interaction by resorting to recent 1 results showing that London dispersion forces between delocalized electrons of base pairs of DNA 2 are responsible for the formation of dipole modes that can be recognized by Taq polymerase. 3 We describe the dynamical origin of the high efficiency and precise targeting of Taq activity in 4 PCR. The spatiotemporal distribution of interaction couplings, frequencies, amplitudes, and phase 5 modulations comprise a pattern of fields instantiating the electromagnetic image of DNA in its 6 water environment, which is what the polymerase enzyme actually recognizes at long range. The 7 experimental realization of PCR amplification, achieved through replacement of the DNA template 8 by the treatment of pure water with electromagnetic signals recorded from viral and bacterial DNA 9 solutions, is found consistent with the gauge theory paradigm of quantum fields.
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Life Sciences, Molecular Biology; Lynch syndrome; segregation analysis; MSH6 gene; hereditary colorectal cancer; oligogenic model
Online: 5 April 2017 (03:04:02 CEST)
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Background: Lynch syndrome, the most frequent form of hereditary colorectal cancer and involves mutations in mismatch repair genes. The aim of this study was to identify mutations in MSH6 from 97 subjects negative for mutations in MLH1 and MSH2. Methods: By direct sequencing, we identified 27 MSH6 variants, of which, nine were novel. To verify the pathogenicity of these novel variants we performed in silico and segregation analyses. Results: Three novel variants were predicted by in silico analysis as damaging mutations and segregated with the disease phenotype. While, a novel frameshift deletion variant that was predicted to yield a premature stop codon, did not segregate with the LS phenotype in 3 of 4 cases in the family. Interestingly, another frame-shift variant identified in this study, already described in the literature, also did not segregate with the LS phenotype in 1 of 2 affected subjects in the family. In all affected subjects of both families, no mutation was detected in other MMR genes. Therefore, it is expected that within these families other genetic factors contribute to the disease either alone or in combination with MSH6 variants. Conclusion: We conclude that caution should be exercised in counseling for MSH6-associated LS family members.
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Life Sciences, Molecular Biology; NF-кB, Hypoxia, Inflammation, IKK, PHDs, Cancer, TAK1, FIH
Online: 31 March 2017 (17:21:52 CEST)
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Cancer is often characterised by the presence of hypoxia and inflammation. Paramount to the mechanisms controlling cellular responses under such stress stimuli, are the transcription factor families of Hypoxia Inducible Factor (HIF) and Nuclear Factor of kappa-light-chain-enhancer of activated B cells (NF-кB). Although, a detailed understating of how these transcription factors respond to their cognate stimulus is well established, it is now appreciated that HIF and NF-кB undergo extensive crosstalk, in particular in pathological situations such as cancer. Here, we focus on the current knowledge on how HIF is activated by inflammation and how NF-кB is modulated by hypoxia. We summarise the evidence for the possible mechanism behind this activation and how HIF and NF-кB function impacts cancer, focusing on colorectal, breast and lung cancer. We discuss possible new points of therapeutic intervention aiming to harness the current understanding of the HIF-NF-кB crosstalk.
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Life Sciences, Molecular Biology; genetic code; tRNA dimers; self-reference; modularity; error-compensation; metabolism chronology; protein stability; punctuation system
Online: 17 March 2017 (04:55:46 CET)
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The proposal that the genetic code was formed on the basis of protein synthesis directed by tRNA dimers is reviewed and updated. The tRNAs paired through the anticodon loops are an indication on the process. Dimers are considered mimics of the ribosomes – structures that hold tRNAs together and facilitate the transferase reaction, and of the translation process – anticodons are at the same time codons for each other. The primitive protein synthesis system gets stabilized when the product peptides are able to bind the producers therewith establishing a self-stimulating production cycle. The chronology of amino acid encoding starts with Glycine and Serine, indicating the metabolic support of the Glycine-Serine C1-assimilation pathway, which is also consistent with evidence on origins of bioenergetics mechanisms. Since it is not possible to reach for substrates simpler than C1 and compounds in the identified pathway are apt for generating the other central metabolic routes, it is considered that protein synthesis is the beginning and center of a succession of sink-effective mechanisms that drive the formation and evolution of the metabolic flow system. Plasticity and diversification of proteins construct the cellular system following the orientation given by the flow and implementing it. Nucleic acid monomers participate in bioenergetics and the polymers are conservative memory systems for the synthesis of proteins. Protoplasmic fission is the final sink-effective mechanism, part of cell reproduction, guaranteeing that proteins don’t accumulate to saturation, which would trigger inhibition.
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Life Sciences, Molecular Biology; glucose transporter; GLUTs; chicken; avian; mammal; phylogenetic analysis
Online: 15 March 2017 (08:34:06 CET)
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The GLUT members belong to a family of glucose transporter proteins that facilitate glucose transport across the cell membrane. The mammalian GLUT family consists of thirteen members (GLUTs 1-12 and HMIT). Humans have a recently duplicated GLUT member, GLUT14. Avians express the majority of GLUT members. The arrangement of multiple GLUTs across all somatic tissues signifies the important role of glucose across all organisms. Defects in glucose transport have been linked to metabolic disorders, insulin resistance and diabetes. Despite the essential importance of these transporters, our knowledge regarding GLUT members in avians is fragmented. It has been clear that there are no chicken orthologs of mammalian GLUT4 and GLUT7. Our examination of GLUT members in the chicken revealed that some chicken GLUT members do not have corresponding orthologs in mammals. We review the information regarding GLUT orthologs and their function and expression in mammals and birds, with emphasis on chickens and humans.
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Life Sciences, Molecular Biology; miRNAs; pre-miRNAs sequencing; Abelmoschus esculentus; Next generation sequencing; non-model plant
Online: 14 March 2017 (10:15:14 CET)
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MicroRNAs (miRNAs) are crucial regulatory RNAs, originated from hairpin precursors. For the past decade, researchers are focusing extensively on miRNA profiles in various plants. However studies on precursor miRNAs (pre-miRNAs) global profiling stay static even in model plants. Here, for the first time in a non-model plant, Abelmoschus esculentus with negligible genome information, we are reporting the global profiling to characterize the miRNAs and their associated pre-miRNAs by applying next generation sequencing approach. Preliminarily we performed sRNA (small RNA) sequencing with five biological replicates of leaf samples to attain 207,285,863 reads and data analysis using miRPlant keyed out 128 known and 845 novel miRNA candidates. With the objective to seize their associated hairpin precursors, we accomplished pre-miRNA sequencing to attain 83,269,844 reads. The paired end reads are merged, adaptor trimmed and the resulting 40-241 nt (nucleotide) sequences were picked out for analysis by using perl scripts from miRGrep tool and in-house built shell script for Minimum Fold Energy Index (MFEI) calculation. Applying stringent criteria of dicer cleavage pattern and perfect stem loop structure revealed precursors for 57 known miRNAs of 15 families and 18 novel miRNAs. Quantitative Real Time (qRT) PCR was performed to determine the expression of selected miRNAs.
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Life Sciences, Molecular Biology; ovarian cancer; melatonin; angiogenesis; VEGF; VEGFR; HIF-1α
Online: 6 March 2017 (06:34:02 CET)
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Angiogenesis is a hallmark of ovarian cancer (OC) it promotes rapid cell growth and the associated metastasis. Identifying new bioactive compounds to target angiogenesis may provide valuable paradigms as therapeutic strategies. Melatonin is a well-characterized indoleamine that possesses important anti-angiogenic properties in a set of aggressive solid tumors. Herein, we evaluated the role of melatonin therapy on the angiogenic signaling pathway in OC of an ethanol-preferring rat model that mimics the same pathophysiological conditions occurring in women. OC was chemically induced with a single injection of 7,12-dimethylbenz(a)anthracene (DMBA) under the ovarian bursa. After the rats developed serous papillary OC, half of the animals received i.p. injections of melatonin (200 µg/100 g body weight/day) for 60 days. Serum levels of melatonin were higher following therapy, and the expression of its receptor MT1R was significantly increased in OC-bearing rats, regardless of ethanol intake. TGFB1, a transforming growth factor-beta1, was reduced only after melatonin treatment. Importantly, vascular endothelial growth factor (VEGF) was severely reduced after melatonin therapy in animals given or not given ethanol. Conversely, the levels of VEGF receptor 1 (VEGFR1) was diminished after ethanol consumption, regardless of melatonin therapy, and VEGFR2 was only reduced following melatonin. Hypoxia-inducible factor (HIF)-1α was augmented with ethanol consumption, and notably, melatonin significantly reduced their levels. Collectively, our results suggest that melatonin attenuates angiogenesis in OC of an animal model of ethanol consumption; this provides a possible complementary therapeutic opportunity for concurrent OC chemotherapy.
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Life Sciences, Molecular Biology; fructose; obesity; liver; aerobic exercise; strength exercise; combined exercise
Online: 28 February 2017 (12:02:06 CET)
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Fructose consumption has been growing exponentially and, concomitant with this, the increase in the incidence of obesity and associated complications has followed the same behavior. Studies indicate that fructose may be a carbohydrate with greater obesogenic potential than other sugars. In this context, the liver seems to be a key organ for understanding the deleterious health effects promoted by fructose consumption. Fructose promotes complications in glucose metabolism, accumulation of triacylglycerol in the hepatocytes and alterations in the lipid profile, which, associated with an inflammatory response and alterations in the redox state, will imply a systemic picture of insulin resistance. However, physical exercise has been indicated for the treatment of several chronic diseases. In this review, we show how each exercise protocol (aerobic, strength or a combination of both) promote improvements in the obesogenic state created by fructose consumption as an improvement in the serum and liver lipid profile (HDL increase and decrease TG and LDL levels) and a reduction of markers of inflammation caused by an excess of fructose. Therefore, it is concluded that the practice of aerobic physical exercise, strength or a combination of both is essential for attenuating the complications developed by the consumption of fructose.
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Life Sciences, Molecular Biology; alfalfa; drought; microRNA; small RNA; differential expression
Online: 23 February 2017 (09:50:07 CET)
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Alfalfa, an important legume forage, is an ideal crop for sustainable agriculture and a potential bioenergy plant. Drought, one of the most common environmental stresses, substantially affects plants’ growth, development and productivity. MicroRNAs (miRNAs) are newly discovered gene expression regulators that have been linked to several plant stress responses. To elucidate the role of miRNAs in drought stress regulation of alfalfa, a high-throughput sequencing approach was used to analyze 12 small RNA libraries comprising of 4 samples, each with 3 biological replicates. We identified 348 known miRNAs, belonging to 80 miRNA families, from the 12 libraries and 281 novel miRNAs using Mireap software. 18 known miRNAs in roots and 12 known miRNAs in leaves were screened out as drought-responsive miRNAs. Except for miR319d and miR157a which were upregulated under drought stress, the expression pattern of drought-responsive miRNAs were different between roots and leaves in alfalfa. This is the first study discovering miR157a, miR1507, miR3512, miR3630, miR5213, miR5294, miR5368 and miR6173 are drought-responsive miRNAs. Target transcripts of drought-responsive miRNAs were computationally predicted. All 447 target genes for the known miRNAs were predicted using an online tool. This study provides a significant insight on understanding drought-responsive mechanisms of alfalfa.
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Life Sciences, Molecular Biology; blunt snout bream; high carbohydrate; transcriptome; metabolomics; insulin resistance; fatty liver disease
Online: 26 January 2017 (03:52:10 CET)
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A high intake of carbohydrates, associated with obesity, is one of the major causes of fatty liver disease in humans. This study investigated how high carbohydrate intake induces fatty liver disease in Blunt snout bream (Megalobrama amblycephala). Blunt snout bream were fed a high-carbohydrate diet (HCBD) for 60 days. Their growth indices were evaluated, and the transcriptomes, metabolites, biochemistry, and histology of their blood and livers were analyzed. The final weight, weight gain, specific growth rate, and feed conversion ratio were all higher in the HCBD group than in the control group, but not significantly so (P > 0.05). The hepatosomatic index (HSI) differed significantly in the two groups (P < 0.05), and the metabolomics results showed that a high carbohydrate intake induced significant increases in plasma α/β-glucose, succinate, and tyrosine, which could increase hepatic glycogen and triglyceride. Low levels of betaine were also found in the livers of the HCBD group. The histology and blood biochemistry results suggested abnormal liver, with excessive lipid accumulation and liver damage. A transcriptome analysis and quantitative reverse transcription–PCR (RT–qPCR) indicated that the expression of the factors INSR, IRS, PI3K, PDK, AKT, ACC, IL6, AP1, ChREBP-MLX, PEPCK, and FBP in the insulin signaling pathway was significantly upregulated and that of SOCS3, GSK3β, and AMPK significantly downregulated in the HCBD. This pattern is associated with the nonalcoholic fatty liver disease (NAFLD) pathway. This study extends our understanding of how high carbohydrate causes increased fat deposition in the liver, enhanced glycolysis (α/β-glucose) in the plasma, and reduced betaine in the liver. This leads to activation of hepatocyte insulin resistance and lipogenesis by regulating the expression of genes related to fatty liver disease.
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Life Sciences, Molecular Biology; aldo-keto reductases; cigarette smoke; smokeless tobacco products; nicotine; oral cavity cells; xenobiotic metabolism
Online: 25 January 2017 (04:20:07 CET)
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Smoking has been established as a major risk factor for developing oral squamous cell carcinoma (OSCC), but less attention has been paid to the effects of smokeless tobacco products. Our objective is to identify potential biomarkers to distinguish the biological effects of combustible tobacco products from those of non-combustible using oral cell lines. Normal human gingival epithelial cells (HGEC), non-metastatic (101A) and metastatic (101B) OSCC cell lines were exposed to different tobacco product preparations (TPPs) including cigarette smoke total particulate matter (TPM), whole-smoke conditioned media (WS-CM), smokeless tobacco extract in complete artificial saliva (STE), or nicotine (NIC) alone. We performed microarray-based gene expression profiling and found 3456 probe sets from 101A, 1432 probe sets from 101B, and 2717 probe sets from HGEC to be differentially expressed. Gene Set Enrichment Analysis (GSEA) revealed xenobiotic metabolism and steroid biosynthesis were the top two pathways that were upregulated by combustible but not by non-combustible TPPs. Notably, aldo-keto reductase genes, AKR1C1 and AKR1C2, were the core genes in the top enriched pathways and were statistically upregulated more than 8 fold by combustible TPPs. Our qRT-PCR results statistically support AKR1C1 as a potential biomarker for differentiating the biological effects of combustible from non-combustible tobacco products.
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Songzi Zhang,
Huizhu Liu,
Yuxia Liu,
Jie Zhang,
Hongbo Li,
Weili Liu,
Guohong Cao,
Pan Xu,
Jinjin Zhang,
Changjun Lv,
Xiaodong Song
Life Sciences, Molecular Biology; idiopathic pulmonary fibrosis; miR-30a; TET1; Drp-1
Online: 16 January 2017 (04:44:44 CET)
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Several recent studies have indicated that miR-30a plays critical roles in various biological processes and diseases. However, the mechanism of miR-30a participation in the regulation of idiopathic pulmonary fibrosis (IPF) is ambiguous. Our previous study demonstrated that miR-30a may function as a novel therapeutic target for lung fibrosis by blocking mitochondrial fission, which is dependent on dynamin-related protein-1 (Drp-1). However, the regulatory mechanism between miR-30a and Drp-1 has yet to be investigated. In addition, whether miR-30a can act as a potential therapeutic has not been verified in vivo. In this study, the miR-30a expression in IPF patients was evaluated. Computational analysis and a dual luciferase reporter system assay were used to identify the target gene of miR-30a, and cell transfection was used to confirm this relationship. Ten-eleven translocation 1 (TET1) was validated as a direct target of miR-30a, and the transfection of miR-30a mimic/inhibitor significantly reduced/increased the expression of TET1 protein. Further experiment verified that the interference on TET1(siRNA) could inhibit the hydroxymethlation of the Drp-1 promoter. Finally, miR-30a agomir was designed and applied to identify and validate the therapeutic effect of miR-30a in vivo. Our study demonstrated that miR-30a could inhibit the TET1 expression by base pairing with complementary sites in the 3′ untranslated region to regulate the hydroxymethlation of the Drp-1 promoter. Furthermore, miR-30a could act as a potential therapeutic target for IPF.
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Life Sciences, Molecular Biology; cancer; microRNA; gene therapy; oncogene; tumor suppressor gene
Online: 9 January 2017 (10:24:03 CET)
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MicroRNAs (miRNAs) are a kind of conserved small non-coding RNAs that participate in regulating gene expression by targeting multiple molecules. Early studies have shown that the expression of miRNAs changes significantly in different tumor tissues and cancer cell lines. It is well acknowledged that such variation is involved in almost all biological processes, including cell proliferation, mobility, survival and differentiation. Increasing experimental data indicate that miRNA dysregulation is a biomarker of several pathological conditions including cancer, and that miRNA can exert a causal role, as oncogenes or tumor suppressor genes, in different steps of the tumorigenic process. Anticancer therapies based on miRNAs are currently being developed with a goal to improve outcomes of cancer treatment. In our present study, we review the function of miRNAs in tumorigenesis and development, and discuss the latest clinical applications and strategies of therapy targeting miRNAs in cancer.
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Life Sciences, Molecular Biology; Sarcocystis neurona; EPM; docking; apicomplexans; phylogeny; homology modeling
Online: 9 January 2017 (05:19:32 CET)
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The apicomplexan parasite, Sarcocystis neurona causes the degenerative neurological equine protozoal myeloencephalitis (EPM) disease of horses. Due to its host range expansion, S. neurona is an emerging threat that requires close monitoring. In apicomplexans, protein kinases (PKs) have been implicated in a myriad of critical functions such as host cell invasion, cell cycle progression and host immune responses evasion. Here, we used various bioinformatics methods to define the kinome of S. neurona and phylogenetic relatedness of its PKs to other apicomplexans. Further, three-dimensional (3D) homology models for selected S. neurona putative PKs were constructed and evaluated for inhibitor docking. We identified 92 putative PKs clustering within the AGC, CAMK, CK1, CMGC, STE, TKL, aPK and OPK groups. Although containing the universally conserved PKA (AGC group), S. neurona kinome was devoid of PKB and PKC, but contained the six apicomplexan conserved CDPKs (CAMK group). The OPK group was represented by ROPKs 19A, 27, 30, 33, 35 and 37, but was devoid of the virulence-associated ROPKs 5, 6, 18 and 38. Two out of the three S. neurona CK1 enzymes had high sequence similarities to T. gondii TgCK1-α and TgCK1-β and the Plasmodium PfCK1. Docking of four inhibitors onto homology models of putative ROP27 and PKA indicated that inhibition of S. neurona PKs is feasible, but needs to be experimentally tested. The essentiality of apicomplexan PKs makes the elucidation of S. neurona kinome a key milestone for development of novel therapeutics for EPM.
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Life Sciences, Molecular Biology; symbiogenesis; eukaryogenesis; RNA world; expensive brain; human evolution; hydrothermal vent
Online: 4 January 2017 (07:34:07 CET)
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Currently there is little doubt left on the symbiogenetic nature of eukaryotes - genomes of archaeon and bacterium participated in shaping a genome of last eukaryotic common ancestor in equal albeit asymmetric manner, while a merger event itself indicated the advent of a new domain of life. The “symbiogenetic” framework of interaction of two partners is proposed, outlining similar steps essential for three major advents: the origin of life, the origin of complex life and the origin of humans. Given the immense importance of proper energy source for the evolution of life it seems plausible that for any principal increase in complexity, a partnership with a novel energy donor is required. Moreover, a “language” elaborated in the course of communication of partners might have been a prerequisite for a subsequent increase in complexity. Transitions, which led to RNA-protein world, eukaryotes and human brain, resulted in advent of complex languages via communication onsets between two entities in close partnership. Accordingly this further facilitated formation of first cells, multicellular organisms and human society.
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Life Sciences, Molecular Biology; zebrafish; models; evaluation; drugs; cardiotoxicity; genotoxicity
Online: 20 December 2016 (10:34:56 CET)
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Embryonic and larval Danio rerio is increasingly used as a toxicological model to conduct rapid in vivo tests and developmental toxicity assays; the zebrafish features as high genetic homology to mammals; robust phenotypes; and its value in high-throughput genetic and chemical screening have made it a powerful tool to evaluate in vivo toxicity. New methodologies of genome editing as CRISPR/Cas9; ZFN or Talen make it a suitable model to perform studies to pair human genetic diseases as well. This review surveys recent studies; employing zebrafish as experimental model; comparing it with other in vivo and in vitro models; presenting zebrafish as a potent vertebrate tool to evaluate drug toxicity to facilitate more extensive; easy and comprehensive knowledge of new generation drugs.
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Life Sciences, Molecular Biology; contrast induced nephropath; acute myocardial infarction
Online: 21 November 2016 (12:13:30 CET)
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Background: The morbidity of myocardial infarction is keeping raise in this decade. Because of high safety and operability , percutaneous coronary intervention(PCI) has been used to conquer this disease for more than 20 years.An important complication of PCI is contrast induced nephropathy(CIN), which raises our attention. Previously, we started a study to explore the correlation between acute kidney injury and myonecrosis after scheduled percutaneous coronary intervention. Our study showed that the rate of CI-AKI in patients with post-procedural myocardial injury and undergoing elective PCI was higher than that in patients free of injury. Methods: In this study,forty male rats were randomly divided into four groups: control group (n=8), CM group (n=12), AMI group (n=8) and AMI+CM group (n=12), then velocity of renal artery blood flow (VRABF), computer tomography (CT), serum creatinine(Scr), reactive oxidative species (ROS), periodic acid-Schiff (PAS) and TUNEL were used to estimate the injury of kidney. We analyzed 327 non-ST-segment elevation acute coronary syndrome subjects undertaking elective PCI. Serum levels of creatinine (SCr) and the eGFR before coronary angiography, and 24–72 h after contrast administration were recorded to assess the renal function. Results: The data showed that VRABF was lower in AMI+CM group than CM group from 0 minute to 24h and CT number in cortex was higher in AMI+CM group than CM group at 4-hour. As well as the level of Scr in AMI+CM group displayed a significantly increase at 24-hour compared with CM group. The histopathologic scores and percentage of tubular cell apoptosis were higher in AMI+CM group at 24-hour. In 327 patients, we found that CI-AKI occurred more often in subjects with post-procedural myonecrosis (PMN) than in those without PMN (20.8% versus 5.8%, respectively, P=0.001). Conclusion: Compared to the elective patient, the injury of CIN exhibited a higher severity in AMI patient.
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Life Sciences, Molecular Biology; diabetes mellitus; hyperglycemia; cardiomyopathy; lipid toxicity; polyphenols; aspalathin
Online: 17 November 2016 (11:19:37 CET)
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Aspalathin, a C-glucosyl dihydrochalcone, has previously been shown to protect cardiomyocytes against hyperglycemia-induced shifts in substrate preference and subsequent apoptosis. However, the precise gene regulatory network remains to be elucidated. To unravel the mechanism and provide insight into this supposition, the direct effect of aspalathin in an isolated cell-based system, without the influence of any variables, was tested using an H9c2 cardiomyocytes model. Cardiomyocytes were exposed to high glucose (33 mM) for 48 hours before post-treatment with or without aspalathin. Thereafter, RNA was extracted and RT2 PCR Profiler Arrays were used to profile the expression of 336 genes. Results showed that, 57 genes were differentially regulated in the high glucose or high glucose and aspalathin treated groups. STRING analysis revealed lipid metabolism and molecular transport as the biological processes altered after high glucose treatment, followed by inflammation and apoptosis. Aspalathin was able to modulate key regulators associated with lipid metabolism (Adipoq, Apob, Cd36, Cpt1, Pparγ, Srebf1/2, Scd1 and Vldlr), insulin resistance (Igf1, Akt1, Pde3 and Map2k1), inflammation (Il3, Il6, Jak2, Lepr, Socs3, and Tnf13) and apoptosis (Bcl2 and Chuk). Collectively, our results propose that aspalathin could reverse metabolic abnormalities by activating Adipoq while modulating the expression of Pparγ and Srebf1/2, decreasing inflammation via Il6/Jak2 pathway, which together with an observed increased expression of Bcl2 prevents myocardium apoptosis.
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Life Sciences, Molecular Biology; diabetes mellitus; cardiomyopathy; hyperglycemia; oxidative stress; aspalathin; Nrf2
Online: 17 November 2016 (11:07:56 CET)
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Aspalathin (ASP) can protect H9c2 cardiomyocytes against high glucose (HG)-induced shifts in myocardial substrate preference, oxidative stress and apoptosis. While the protective mechanism of aspalathin remains unknown, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged as a key factor for intracellular responses against oxidative stress. Therefore, we hypothesized that aspalathin protects the myocardium against hyperglycemia-induced oxidative damage by up-regulating Nrf2 expression in H9c2 cardiomyocytes and diabetic (db/db) mice. Using an oxidative stress RT2 Profiler PCR array, ASP at a dose of 1 µM was demonstrated to protect H9c2 cardiomyocytes against HG-induced oxidative stress, but silencing of Nrf2 abolished this protective response of ASP and exacerbated cardiomyocyte apoptosis. Db/db mice and their non-diabetic (db/+) littermate controls were subsequently treated daily for 6 weeks with either a low (13 mg/kg) or high (130 mg/kg) ASP dose. Compared to nondiabetic mice the db/db mice presented increased cardiac remodeling and enlarged left ventricular wall that occurred concomitant to enhanced oxidative stress. Daily treatment of mice with ASP at a dose of 130 mg/kg for 6 weeks was more effective at reversing complications than both a low dose ASP or metformin, eliciting enhanced expression of Nrf2 and its downstream antioxidant genes. These results indicate that ASP maintains cellular homeostasis and protects the myocardium against hyperglycemia-induced stress through activation of Nrf2 and its downstream target genes.
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Life Sciences, Molecular Biology; bacillithiol; Bacillus; oxidative stress; tRNA
Online: 17 November 2016 (10:40:58 CET)
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Oxidative stress occurs when cells are exposed to elevated levels of reactive oxygen species that could damage biological molecules. One bacterial response to oxidative stress involves disulfide bond formation either between protein thiols or between protein thiols and low-molecular-weight thiols. Bacillithiol was recently identified as a major low-molecular-weight thiol in Bacillus subtilis and related Firmicutes. Four genes (bshA, bshB1, bshB2 and bshC) are involved in bacillithiol biosynthesis. The bshA and bshB1 genes are part of a seven-gene operon (ypjD), which includes the essential gene cca, encoding CCA-tRNA nucleotidyltransferase. The inclusion of cca in the operon containing bacillithiol biosynthetic genes suggests that the integrity of the 3’ terminus of tRNAs may also be important in oxidative stress. Addition of the 3´ terminal CCA sequence by CCA-tRNA nucleotidyltransferase to give a mature tRNA and functional molecules ready for aminoacylation plays an essential role during translation and expression of the genetic code. Any defects in these processes, for example, the accumulation of shorter and defective tRNAs under oxidative stress, could exert a deleterious effect on cells. This review summarizes the physiological link between tRNACys regulation and oxidative stress in Bacillus.
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Life Sciences, Molecular Biology; data exchange; resource donations; text mining
Online: 5 October 2016 (15:08:32 CEST)
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Bio-molecular reagents like antibodies required in experimental biology are expensive and their effectiveness, among other things, is critical to the success of the experiment. Although such resources are sometimes donated by one investigator to another through personal communication between the two, there is no previous study to our knowledge on the extent of such donations, nor a central platform that directs resource seekers to donors. In this paper, we describe, to our knowledge, a first attempt at building a web-portal titled Bio-Resource Exchange that attempts to bridge this gap between resource seekers and donors in the domain of experimental biology. Users on this portal can request for or donate antibodies, cell-lines and DNA Constructs. This resource could also serve as a crowd-sourced database of resources for experimental biology. Further, in order to index donations outside of our portal, we mined scientific articles to find instances of donations of antibodies and attempted to extract information about these donations at the finest granularity. Specifically, we extracted the name of the donor, his/her affiliation and the name of the antibody for every donation by parsing the acknowledgements sections of articles. To extract annotations at this level, we propose two approaches – a rule based algorithm and a bootstrapped relation learning algorithm. The algorithms extracted donor names, affiliations and antibody names with average accuracies of 57% and 62% respectively. We also created a dataset of 50 expert-annotated acknowledgements sections that will serve as a gold standard dataset to evaluate extraction algorithms in the future. Contact: madhavi@pitt.edu, madhavi@cs.cmu.edu Database URL: http://tonks.dbmi.pitt.edu/brx Supplementary information: Supplementary data are available at Database online.