REVIEW | doi:10.20944/preprints201707.0035.v1
Online: 14 July 2017 (11:59:25 CEST)
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.
REVIEW | doi:10.20944/preprints202202.0078.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Cardiology; Oncology; CSC; TNBC; TGF-β
Online: 7 February 2022 (11:19:03 CET)
Triple-negative breast cancer (TNBC) is a subtype of breast cancer that disproportionally accounts for the majority of breast cancer-related deaths due to the lack of specific targets for effective treatments. While there is immense focus on the development of novel therapies for TNBC treatment, a persistent and critical issue is the rate of heart failure and cardiomyopathy which is a leading cause of mortality and morbidity amongst cancer survivors. In this review, we highlight mechanisms of cardiotoxicity post-chemotherapeutic exposure, assess how this is assessed clinically and highlight the transforming growth factor-beta family (TGF-β) pathway and discuss its role as a mediator of cardiomyopathy. We highlight recent findings demonstrating TGF-β inhibition as a potent method to prevent cardiac re-modeling, fibrosis and cardiomyopathy. We describe how dysregulation of the TGF-β pathway is associated with negative patient outcomes across 32 types of cancer including TNBC. We then highlight how TGF-β modulation may be a potent method to target mesenchymal (CD44+/CD24-) and epithelial (ALDHhigh) cancer stem cell (CSC) populations in TNBC models. CSCs are associated with tumorigenesis, metastasis, relapse, resistance, and diminished patient prognosis; however, due to plasticity and differential regulation these populations remain difficult to target and persist as a major barrier barring successful therapy. TGF-β inhibition represents an intersection of two fields: cardiology and oncology. Through inhibiting cardiomyopathy, cardiac damage and heart failure may be prevented and through CSC targeting, patient prognosis may be improved. Together, both approaches, if successfully implemented would target the two greatest causes of cancer-related morbidity in patients and potentially lead to a breakthrough therapy.
ARTICLE | doi:10.20944/preprints201808.0516.v1
Subject: Chemistry, Medicinal Chemistry Keywords: ALK5 inhibitor; TGF-β; kinase assay; selectivity; docking
Online: 30 August 2018 (05:52:08 CEST)
The transforming growth factor-β (TGF-β), in which overexpression have been associated with various diseases, has become an attractive molecular target for the treatment of cancers. Three series of 3-substituted-4-(quinoxalin-6-yl) pyrazoles 14a–h, 15a–h, 16a–h, 22a, 22b, 22d, 23a, 23b, 23d, 24b, and 24d were synthesized and evaluated for their activin receptor-like kinase 5 (ALK5) and p38α mitogen activated protein (MAP) kinase inhibitory activity in an enzymatic assays. Among these compounds, the most active compound 16f inhibited ALK5 phosphorylation with an IC50 value of 0.28 µM, with 98% inhibition at 10 µM. Compound 16f also had good selectivity index of >35 against p38α MAP kinase, with 9.0-fold more selective than clinical candidate, compound 3 (LY-2157299). Molecular docking study was performed to identify the mechanism of action of the synthesized compounds and their good binding interactions were observed. ADMET prediction of good active compounds showed that these ones possess good pharmacokinetics and drug-likeness behavior.
REVIEW | doi:10.20944/preprints202109.0047.v2
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Triple Negative Breast Cancer; Cancer Stem Cell; TGF-β
Online: 8 September 2021 (20:53:29 CEST)
Triple-negative breast cancer (TNBC) is a subtype of breast cancer that disproportionally accounts for the majority of breast cancer-related deaths due to the lack of specific targets for effective treatments. In this review, we highlight the complexity of the transforming growth factor-beta family (TGF-β) pathway and discuss how the dysregulation of the TGF-β pathway promotes oncogenic attributes in TNBC which negatively affects patient prognosis. Moreover, we discuss recent findings highlighting TGF-β inhibition as a potent method to target mesenchymal (CD44+/CD24-) and epithelial (ALDHhigh) cancer stem cell (CSC) populations. CSCs are associated with tumorigenesis, metastasis, relapse, resistance, and diminished patient prognosis; however, due to differential signal pathway enrichment and plasticity, these populations remain difficult to target and persist as a major barrier barring successful therapy. This review highlights the importance of TGF-β as a driver of chemoresistance, radioresistance and reduced patient prognosis in breast cancer and highlights novel treatment strategies which modulate TGF-β, impede cancer progression and reduce the rate of resistance generation via targeting the CSC populations in TNBC and thus reducing tumorigenicity. Potential TGF-β inhibitors targeting based on clinical trials are summarized for further investigation which may lead to the development of novel therapies to improve TNBC patient prognosis.
REVIEW | doi:10.20944/preprints202103.0444.v1
Subject: Medicine & Pharmacology, Allergology Keywords: SMAD; Sjӧgren’s syndrome; epithelial-mesenchymal transition; fibrosis; TGF-β; inflammation
Online: 17 March 2021 (14:43:37 CET)
There is considerable interest in delineating the molecular mechanisms of action of transforming growth factor-β (TGF-β), considered as central player in a plethora of human conditions, including cancer, fibrosis and autoimmune disease. TGF-β elicits its biological effects through membrane bound serine/threonine kinase receptors which transmit their signals via downstream signalling molecules, SMADs, which regulate the transcription of target genes in collaboration with various co-activators and co-repressors. Until now, therapeutic strategy for primary Sjӧgren’s syndrome (pSS) has been focused on inflammation, but, recently, the involvement of TGF-β/SMADs signalling has been demonstrated in pSS, although TGFβ family members seems to have ambiguous effects on the function of pSS salivary glands. Based on these premises, this review highlights recent advances in unravelling the molecular basis for the multi-faceted functions of TGF-β in pSS that are dictated by orchestrations of SMADs, and describe TGF-β/SMADs value as both disease markers and/or therapeutic target for pSS.
ARTICLE | doi:10.20944/preprints202010.0572.v1
Subject: Life Sciences, Biochemistry Keywords: aging; collagen; extracellular matrix; fibroblast; skin; tenascin C; TGF-β
Online: 28 October 2020 (08:49:54 CET)
Tenascin C (TNC) is an element of the extracellular matrix (ECM) of various tissues, including the skin, and is involved in modulating ECM integrity and cell physiology. Although skin aging is apparently associated with changes in the ECM, little is known about the role of TNC in skin aging. Here we found that Tnc mRNA level was significantly reduced in the skin tissues of aged mice compared with young mice, consistent with reduced TNC protein expression in aged human skin. TNC-large (TNC-L; 330-kDa) and -small (TNC-S; 240-kDa) polypeptides were observed in conditional media from primary dermal fibroblasts. Both recombinant TNC polypeptides, corresponding to TNC-L and TNC-S, increased the expression of type I collagen and reduced the expression of matrix metalloproteinase-1 in fibroblasts. Treatment of fibroblasts with a recombinant TNC polypeptide, corresponding to TNC-L, induced phosphorylation of SMAD2 and SMAD3. TNC increased the level of TGF-β1 mRNA and upregulated the expression of type I collagen by activating the TGF-β signaling pathway. In addition, TNC also promoted the expression of type I collagen in fibroblasts embedded in a three-dimensional collagen matrix. Our findings suggest that TNC contributes to the integrity of ECM in young skin and to prevention of skin aging.
REVIEW | doi:10.20944/preprints201805.0355.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: TGF-β; cancer; immunosuppression; TAK1; mechanobiology; extracellular matrix; tensegrity; DNA damage
Online: 25 May 2018 (08:37:53 CEST)
TGF-β signaling transduces immunosuppressive biochemical and mechanical signals in the tumor microenvironment. In addition to canonical SMAD signaling, TGF-β can promote tumor growth and survival by inhibiting proinflammatory signaling and extracellular matrix remodeling. In this article, we will review how TAK1 activation lies at the intersection of proinflammatory signaling by immune receptors and anti-inflammatory signaling by TGF-β receptors. Additionally, we will discuss the role of TGF-β in the mechanobiology of cancer. Understanding how TGF-β dampens proinflammatory responses and induces pro-survival mechanical signals throughout cancer development will be critical in designing therapeutics which inhibit tumor progression while bolstering the immune response.
REVIEW | doi:10.20944/preprints201805.0180.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: BMP; TGF-β; signaling; sex; chromosomes; XIST; genomic imprinting; hormones; fibrosis
Online: 11 May 2018 (09:49:48 CEST)
Crosstalk between the BMP and TGF-β signaling pathways regulates many complex developmental processes from the earliest stages of embryogenesis throughout adult life. In many situations, the two signaling pathways act reciprocally. For example, TGF-β signaling is generally pro-fibrotic whereas BMP signaling is anti-fibrotic and pro-calcific. Sex-specific differences occur in many diseases including cardiovascular pathologies. Differing ratios of fibrosis and calcification in stenotic valves suggests that BMP/TGF-β signaling may vary in men and women. In this review, we focus on the current understanding of the interplay between sex and BMP/TGF-β signaling and pose several unanswered questions.
ARTICLE | doi:10.20944/preprints202006.0093.v1
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: myasthenia gravis; thymic stromal lymphopoietin; regulatory T cells; TGF- β; IL-10
Online: 7 June 2020 (15:00:37 CEST)
Thymic stromal lymphopoietin (TSLP) is a cytokine and is closely related to Interleukin (IL) - 7, and hTSLP can activation through the human thymus dendritic cell in thymic to indirectly promote the differentiation of natural Regulatory T cells (Tregs) of the thymus. In this study, we focused on recombinant TSLP to determine its effects on the differentiation of CD4+CD25-T cells separated from the thymus of myasthenia gravis (MG) patients. Our results demonstrated that exogenous TSLP could increase CD4+CD25+T/CD4+T cells ratio, up-regulate the expression of Foxp3 mRNA and protein expression in CD4+CD25+Treg cells. Furthermore, we found that CD4+CD25+ Treg cells induced by exogenous TSLP could secrete IL - 10, Transforming growth factor (TGF) - β and the ability to inhibit CD4+T cell proliferation improved. These results indicate that TSLP may promote the differentiation of thymic CD4+CD25-T cells of MG patient to CD4+CD25+Foxp3+ regulatory T cells and enhance the function of immune suppression.
ARTICLE | doi:10.20944/preprints201905.0171.v1
Subject: Life Sciences, Biochemistry Keywords: Trypanosoma cruzi; TGF-β; heart fibrosis; extracellular matrix; signaling pathways; SMAD2; p-38 MAPK; c-Jun
Online: 14 May 2019 (12:28:59 CEST)
Transforming growth factor beta (TGF-β) is a determinant for inflammation and fibrosis in cardiac and skeletal muscle in Chagas disease. To determine its regulatory mechanisms, we investigated the response of T. cruzi-infected cardiomyocytes (CM), cardiac fibroblasts (CF) and L6E9 skeletal myoblasts to TGF-β. Cultures of CM, CF and L6E9 were infected with T. cruzi (Y strain) and treated with TGF-β (1–10 ng/mL, 1h or 48 h). Fibronectin (FN) distribution was analyzed by immunofluorescence and Western blot (WB). Phosphorylated SMAD2 (PS2), phospho-p38 (p-p38), and phospho-c-Jun (p-c-Jun) signaling were evaluated by WB. CF and L6E9 showed an increase in FN from 1 ng/mL of TGF-β, while CM displayed FN modulation only after 10 ng/mL treatment. CF and L6E9 showed higher PS2 levels than CM, while p38 is less stimulated in CF than CM and L6E9. After T. cruzi infection, localized FN disorganization was observed in infected CF and L6E9. T. cruzi induced an increase in FN in CF cultures, mainly in uninfected cells. Infected CF cultures treated with TGF-β showed a reduction in PS2 and an increase in p-p38 and p-c-Jun levels. Our data suggest that p38 and c-Jun pathways may be participating in the fibrosis regulatory process mediated by TGF-β after T. cruzi infection.
REVIEW | doi:10.20944/preprints201908.0234.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: osteoarthritis; articular cartilage; degeneration; regeneration; therapeutic protein; growth factor; protein production platform; protein packaging cell line; transforming growth factor β (TGF-β); GP2-293 cells
Online: 23 August 2019 (03:33:49 CEST)
This article focuses on the current state-of-the-art in the area of cellular and molecular biotechnology for over-production of clinically relevant therapeutic growth factors and how the technology can be used for the treatment of osteoarthritis (OA). Transfected and irradiated protein packaging cell lines may be used as “cellular factories” for large-scale production of therapeutic proteins and pro-anabolic growth factors, particularly in the context of cartilage matrix regeneration. We discuss the potential for new innovations in regenerative medicine for degenerative diseases of synovial joints using mammalian protein production platforms, specifically protein packaging cell lines, for over-producing growth factors for cartilage tissue regeneration and give recent examples. Mammalian protein production platforms that incorporate protein packaging cell lines are superior to bacterial expression systems and are likely to have a significant impact on the development of new biological therapies for treating focal cartilage defects and more generally for the treatment of degenerative joint diseases such as OA.
ARTICLE | doi:10.20944/preprints201907.0140.v1
Subject: Life Sciences, Molecular Biology Keywords: PlGF; PGF; blood-retinal barrier; RNA Seq; HREC; gene ontology; fastQC; Trimmomatic; KEGG; pentose phosphate pathway; TGF-β
Online: 10 July 2019 (07:48:20 CEST)
Placental growth factor (PlGF or PGF) is a member of the VEGF family, which is known to play a critical role in pathological angiogenesis, inflammation, and endothelial cell barrier function. However, the molecular mechanisms by which PlGF mediates its effects in non-proliferative diabetic retinopathy (DR) remain elusive. In this study, we performed transcriptome-wide profiling of differential gene expression for human retinal endothelial cells (HRECs) treated with PlGF antibody. The effect of antibody treatment on the samples was validated using trans-endothelial electric resistance (TEER), and western blot. A total of 3760 genes (1750 upregulated and 2010 downregulated) were found to be differentially expressed between the control and PlGF antibody treatment group. These differentially expressed genes (DEGs) were used for gene ontology and enrichment analysis to identify gene function, signal pathway, and interaction networks. The gene ontology results revealed that catalytic activity (GO:0003824) of molecular function, cell (GO:0005623) of the cellular component, and cellular process (GO:0009987) were among the most enriched biological processes. Pathways such as TGF-β, VEGF-VEGFR2, p53, apoptosis, pentose phosphate pathway, and ubiquitin-proteasome pathway, were among the most enriched, and TGF-β1 was identified as a primary upstream regulator. These data provide new insights into the underlying molecular mechanisms of PlGF in mediating biological functions, in relation to DR.
REVIEW | doi:10.20944/preprints202007.0674.v1
Subject: Biology, Physiology Keywords: osteoarthritis; articular cartilage; degeneration; regeneration; therapeutic protein; growth factor; protein production platform; protein packaging cell line; transforming growth factor β (TGF-β); GP2-293 cells; TissueGene-C
Online: 28 July 2020 (10:16:51 CEST)
This review article focuses on the current state-of-the-art in the area of cellular and molecular biotechnology for over-production of clinically relevant therapeutic and anabolic growth factors. We discuss how the currently available tools and emerging technologies can be used for the regenerative treatment of osteoarthritis (OA). Transfected protein packaging cell lines such as GP-293 cells may be used as “cellular factories” for large-scale production of therapeutic proteins and pro-anabolic growth factors, particularly in the context of cartilage regeneration. However, when irradiated with gamma or x-rays, these cells lose their capacity for replication, which actually makes them safe for use as a live cell component of intra-articular injections. This innovation is already here, in the form of TissueGene-C, a new biological drug which consists of normal allogeneic primary chondrocytes combined with transduced GP2-293 cells that overexpress the growth factor transforming growth factor β1 (TGF-β1). TissueGene-C has revolutionized the concept of cell therapy, allowing drug companies to develop live cells as biological drug delivery systems for direct intra-articular injection of growth factors whose half-lives are in the order of minutes. Therefore, in this paper, we discuss the potential for new innovations in regenerative medicine for degenerative diseases of synovial joints using mammalian protein production platforms, specifically protein packaging cell lines, for over-producing growth factors for cartilage tissue regeneration and give recent examples. Mammalian protein production platforms that incorporate protein packaging eukaryotic cell lines are superior to prokaryotic bacterial expression systems and are likely to have a significant impact on the development of new humanized biological growth factor therapies for treating focal cartilage defects and more generally for the treatment of degenerative joint diseases such as OA, especially when injected directly into the joint.
REVIEW | doi:10.20944/preprints201912.0135.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: vascular homing peptide; cell penetrating peptide; angiogenesis; vascular heterogeneity; fibrosis; targeted delivery; decorin; transforming growth factor-β (tgf-β), bystander effect, cendr peptide; tissue regeneration; regenerative medicine
Online: 10 December 2019 (15:02:39 CET)
Growth factors, chemokines and cytokines guide tissue regeneration after injuries. However, their applications as recombinant proteins are almost non-existent due to the difficulty of maintaining their bioactivity in the protease-rich milieu of injured tissues in humans. Safety concerns have ruled out their systemic administration. The vascular system provides a natural platform for circumvent the limitations of the local delivery of protein-based therapeutics. Tissue selectivity in drug accumulation can be obtained as organ-specific molecular signatures exist in the blood vessels in each tissue, essentially forming a postal code system (“vascular zip codes”) within the vasculature. These target-specific “vascular zip codes” can be exploited in regenerative medicine as the angiogenic vasculature forming in the regenerating tissues has a unique molecular signature. The identification of vascular homing peptides capable of finding these unique “vascular zip codes” after their systemic administration provides an opportunity for the target-specific delivery of therapeutics to tissue injuries. Therapeutic proteins can be “packaged” together with homing peptides by expressing them as multi-functional recombinant proteins. These multi-functional recombinant proteins provide an example how molecular engineering gives a compound an ability to home to regenerating tissue and enhance its therapeutic potential. Regenerative medicine has been dominated by the locally applied therapeutic approaches despite these therapies are not moving to clinical medicine with success. There might be a time to change the paradigm towards systemically administered, target organ-specific therapeutic molecules in future drug discovery and development for regenerative medicine
REVIEW | doi:10.20944/preprints202204.0189.v1
Subject: Life Sciences, Other Keywords: astrocytes; reactive astrogliosis; TGF-β; traumatic brain injury; stroke; aging; Alzheimer’s disease; Parkinson’s disease; amyotrophic lateral sclerosis; multiple sclerosis; epilepsy
Online: 20 April 2022 (09:06:47 CEST)
Astrocytes are essential for normal brain development and functioning. They respond to brain injury and disease through a process referred to as reactive astrogliosis, where the reactivity is highly heterogenous and context dependent. Reactive astrocytes are active contributors to brain pathology and can exert beneficial, detrimental, or mixed effects following brain insults. Transforming growth factor-β (TGF-β) has been identified as one of the key factors regulating astrocyte reactivity. Genetic and pharmacological manipulation of TGF-β signaling pathway in animal models of CNS injury and disease alters pathological and functional outcomes. This review aims to provide recent understanding regarding astrocyte reactivity and TGF-β signaling in brain injury, aging, and neurodegeneration. Further, it explores how TGF-β signaling modulates astrocyte reactivity and function.
ARTICLE | doi:10.20944/preprints202208.0030.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: ascending aorta aneurysm; bicuspid aorta valve; tricuspid aorta valve; ERG transcriptional factor pathway; TGF-β-SMAD, Notch, and NO pathways modulation.
Online: 2 August 2022 (03:43:22 CEST)
Abstract: The pathobiology of ascending aorta aneurysms (AAA) onset and progression is not well understood and only partially characterized. AAA are also complicated in case of bicuspid aorta valve (BAV) anatomy. There is emerging evidence about the crucial role of endothelium-related pathways, which show in AAA an altered expression and function. Here, we examined the involvement of ERG-related pathways in the differential progression of disease in aortic tissues from patients having a BAV or tricuspid aorta valve (TAV) with or without AAA. Our findings identified ERG as a novel endothelial-specific regulator of TGF-β-SMAD, Notch, and NO pathways, by modulating a differential fibrotic or calcified AAA progression in BAV and TAV aortas. We provided evidence that calcification is correlated to different ERG expression (as gene and protein), which appears to be under control of Notch signaling. The latter, when increased, associated with an early calcification in aortas with BAV valve and aneurysmatic, was demonstrated to favor the progression versus severe complications, i.e., dissection or rupture. In TAV aneurysmatic aortas, ERG appeared to modulate fibrosis. Therefore, we proposed that ERG may represent a sensitive tissue biomarker to monitor AAA progression and a target to develop therapeutic strategies and influence surgical procedures.
ARTICLE | doi:10.20944/preprints202111.0343.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Corrosive burn; esophageal stricture; TGF-β1
Online: 19 November 2021 (09:39:39 CET)
Corrosive burns lead to progressive esophageal stricture and dysphagia. There are many trials to prevent Esophageal stricture formation after corrosive burn. This study aimed to access the effects of EW-7197 on prevention for esophageal stricture formation after corrosive esophageal burn. animal study were classified divided into three groups: a healthy group, a control group (corrosive burn without EW-7197), and a treatment group (corrosive burn with EW-7197). Corrosive esophageal burns were produced using 30% NaOH on the lower esophagus. For 3 weeks, the control group received vehicle and the treatment group received 20 mg/kg/day EW-7197. Treatment efficacy was assessed by measuring the stenosis ratio by esophagogram with contrast media on day 21. histologic staining was performed to evaluate the fibrosis area ratio, and western blotting was performed to evaluate fibrotic markers. Among 20 rats that underwent surgery, 14 survived. Three in the treatment group died because of esophageal perforation, and three in the control group died due to their debilitating status. The esophageal stenosis ratio was significantly lower in the treatment group than in the control group (12.1 ± 9.5% and 42.2 ± 8.3%, respectively; p = 0.001). The histologic fibrosis area ratio was also significantly lower in the treatment group (12.5 ± 3.0% and 21.6 ± 2.1%, respectively; p = 0.001). The treatment group showed lower expressions of profibrogenic proteins such as TGF-β1, pSmad3, and α-SMA. EW-7197 may be a good alternative for the prevention esophageal stricture formation after corrosive burn.
ARTICLE | doi:10.20944/preprints202008.0118.v1
Subject: Life Sciences, Other Keywords: Sarcopenia; β-hydroxy-β-methyl butyrate Calcium; Black ginger
Online: 5 August 2020 (09:51:06 CEST)
Muscle mass and strength decrease with aging, but habitual exercise can maintain muscle health. β-Hydroxy-β-methyl butyrate calcium (HMB) and black ginger (BG) are anti-oxidants that have been reported to improve muscle protein metabolism and energy production; these molecules may have synergistic effects. The senescence-accelerated mouse-prone 8 (SAMP8) model is a useful model of muscle aging. Therefore, in this study, we explored how the combination of habitual exercise, HMB, and BG affected muscle aging. We used 28-week-old SAMP8 mice divided into five groups: control, exercise (Ex), Ex+BG, Ex+HMB, and Ex+BG+HMB (Ex+Comb). Mice were required to run on a treadmill for 16 weeks at 5 days per week. In 44-week-old mice, grip strength tests and dissection were conducted. Muscle weight was measured, and the gastrocnemius muscle was subjected to quantitative polymerase chain reaction and immunoblotting. Muscle mass and strength were preserved in the Ex+Comb group, and mitochondrial function was preserved through suppressing oxidative stress. Muscle protein synthesis signaling was improved in the Ex+Comb group. Autophagy and the ubiquitin system were normalized by Ex+Comb treatment. Overall, habitual exercise and HMB plus BG treatment maintained muscle health by suppressing oxidative stress, preserving mitochondrial function, and maintaining muscle protein metabolism in SAMP8 mice.
ARTICLE | doi:10.20944/preprints201705.0165.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: β-hydroxy-β-methylbutyrate, anti-inflamatory cytokines, resistance exercise
Online: 23 May 2017 (07:30:43 CEST)
The aim of this study was to investigate the effect of β-Hydroxy-β-methylbutyrate (HMB) supplementation on anti-inflammatory cytokines including IL-4, IL-10 and TGF-β during an acute bout of resistance exercise (RE) in young resistance trained men. Ten resistance-trained men in a randomized, double-blind, placebo-controlled and crossover study, were administered a 7-day HMB supplementation (3×1 g.d-1 of HMB) and placebo (3×1 g.d-1 of Maltodextrin) with a 7 days washout period. After supplementation periods, subjects performed three sets of bench press, lat pull down, leg extension, leg curl, biceps curl, triceps curl and shoulder press to failure with 85% of one repetition to maximum (1RM). Blood samples were obtained before- (Pre), immediately post- (IP) and 1 hour-post RE (1h P) to assess serum concentrations of IL-4, IL-10 and TGF-β1. The data were analyzed using 2 (treatment: HMB and PL) × 3 (time points: Pre, IP and 1hP) repeated measures analysis of variance (ANOVA) followed by the Bonferroni post hoc test with a significant level of p<0.05. Serum IL-4 was significantly higher at IP resistance exercise in HMB compared to placebo. Circulating IL-4 and TGF-β1 were significantly raised at IP compared to Pre in both HMB and placebo treatments. No significant differences between treatments were observed for IL-10 and TGF-β1at any time points. In conclusion, HMB supplementation increased the circulating level of IL-4 during RE in resistance-trained men, which may attenuate inflammation and facilitate adaptation to RE.
ARTICLE | doi:10.20944/preprints202012.0622.v1
Subject: Earth Sciences, Atmospheric Science Keywords: GPS; TGF; ERA-5; lightning; geostationary; water vapour
Online: 24 December 2020 (13:22:37 CET)
In this article we report the first investigation over time of the atmospheric conditions around TGFs occurrence, using GPS sensors in combination with geostationary satellite observations and ERA5 reanalyses data. The goal is to understand which characteristics are favourable to the development of these events and to investigate if any precursor signals can be expected. A total of 9 TGFs, occurred at a distance lower than 45 km from a GPS sensor, were analysed and two of them are shown here as an example analysis. Moreover, the lightning activity, collected by the World Wide Lightning Location Network (WWLLN) was used in order to identify any links and correlations with TGF occurrence and PWV trends. The combined use of GPS and the stroke rate trends identified, for all cases, a recurred pattern in which an increase of PWV is observed on a timescale of about two hours before the TGF occurrence that can be placed within the lightning peak. The temporal relation between the PWV trend and TGF occurrence is strictly related to the position of GPS sensors in relation to TGF coordinates. The life cycle of these storms observed by geostationary sensors, described TGFs producing clouds as intense with a wide range of extensions and, in all cases, the TGF is located at the edge of the convective cell. Furthermore, the satellite data give an added value in associating the GPS water vapor trend to the convective cell generating the TGF. The investigation with ERA5 reanalyses data showed that TGFs mainly occur in convective environment with not exceptional values with respect to the monthly average value of parameters measured in the same location. Moreover the analysis showed the strong potential of the use of GPS data for the troposphere characterization in areas with complex territorial morphology. This study provided indications on the dynamics of convective systems linked to TGFs and will certainly help refine our understanding on their production highlights a potential approach through the use of GPS data to explore the lightning activity trend and the TGFs occurrence.
ARTICLE | doi:10.20944/preprints202004.0318.v1
Subject: Life Sciences, Other Keywords: Alzheimer’s disease; amyloid β; β-secretase; bax; caspase; lamiaceae; mint; oxidative stress
Online: 19 April 2020 (03:57:56 CEST)
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that develops as a consequence of different factors such as oxidative stress and accumulation of the protein amyloid β (Aβ) in the brain, resulting in apoptosis of neuronal cells. The search for a treatment for this disorder is essential as current medications are limited to alleviating symptoms and palliative effects. The aim of this study is to investigate the effects of mint extracts on selected mechanisms implicated in the development of AD. To enable a thorough investigation of mechanisms, including effects on -secretase (the enzyme the leads to the formation of A), on Aβ aggregation, and on oxidative stress and apoptosis pathways, a neuronal cell model, SH-SY5Y cells was selected. Six Mentha taxa were investigated for their in vitro β-secretase (BACE) and Aβ-aggregation inhibition activities. Also, their neuroprotective effects on H2O2-induced oxidative stress and apoptosis in SH-SY5Y cells were evaluated through caspase activity. Real-time PCR and Western blot analysis were carried out for the two most promising extracts to determine their effects on signalling pathways in SH-SY5Y cells. All mint extracts had strong BACE inhibition activity. M. requienii extracts showed excellent inhibition of Aβ-aggregation, while other extracts showed moderate inhibition. M. diemenica and M. requienii extracts lowered caspase activity. Exposure of SH-SY5Y cells to M. diemenica extracts resulted in a decrease in the expression of pro-apoptotic protein, Bax, and an elevation in the anti-apoptotic protein, Bcl-xL, potentially mediated by down-regulation of ASK1-JNK pathway. These results indicate that mint extracts could prevent the formation of Aβ and also could prevent their aggregation if they had already formed. M. diemenica and M. requienii extracts have potential to suppress apoptosis at the cellular level. Hence, mint extracts could provide a source of efficacious compounds for a therapeutic approach for AD.
ARTICLE | doi:10.20944/preprints201908.0090.v1
Online: 7 August 2019 (09:42:06 CEST)
Pyrrole-imidazole (PI) polyamides are novel gene silencers that strongly bind the promoter region of target genes in a sequence-specific manner to inhibit gene transcription. We developed a PI polyamide targeting human TGF-b1 (hTGF-b1). To develop PI polyamide targeting hTGF-b1 (Polyamide) as a practical medicine for progressive renal diseases, we examined the effects of Polyamide in two common marmoset models of nephropathy.We performed lead optimization of PI polyamides targeting hTGF-b1 by the dose-dependent inhibition of the PMA-stimulated expression of TGF-b1 mRNA in marmoset fibroblasts. Marmosets were housed with a 0.05% NaCl and magnesium diet and treated with cyclosporine A (CsA; 37.5 mg/kg/day, 8 weeks) to establish chronic nephropathy. Marmosets with nephropathy were treated with Polyamide (1 mg/kg/week, 4 weeks). We also established a unilateral urethral obstruction(UUO) model and examined the effects of Polyamide (1 mg/kg/week, 4 times) in marmosets.Histologically, the renal medulla from CsA-treated marmosets showed cast formation and interstitial fibrosis in the renal medulla. Immunohistochemistry showed strong staining of Polyamide in the renal medulla from CsA-treated marmosets.Polyamidetreatment (1 mg/kg/week, 4 times) reduced hTGF-b1 staining and urinary protein excretion in CsA-treated marmosets. Polyamide reduced the glomerular injury score (GIS) and tubulointerstitial injury score (TIS) in UUO kidneys from marmosets. Polyamide significantly suppressed the hTGF-b1 and Snail mRNA expressionin UUO kidneys from marmosets.PI polyamide effectively improved CsA- and UUO-associated nephropathy, indicating its potential application in the prevention of renal fibrosis in progressive renal diseases.
ARTICLE | doi:10.20944/preprints201812.0356.v1
Subject: Life Sciences, Genetics Keywords: cancer biomarker; DEGs; FC; β-divergence method; β-weight function; paired SAM; robustness
Online: 29 December 2018 (06:45:39 CET)
Background: Identification of cancer biomarkers that are differentially expressed (DE) under two biological conditions is an important task in many microarray studies. There exist several methods in the literature in this regards and most of these methods designed especially for unpaired samples, which does not satisfy the requirements of paired samples where the gene expressions are taken from the same patients before and after treatment. Furthermore, the traditional biomarker identification methods based on either p-values or fold change (FC) values. However, sometimes, p-value based results do not comply with FC based results due to the smaller variance of gene expressions. There are some methods that combine both p-values and FC values to solve this problem. But, these methods also show weak performance for small-sample case in presence of outlying expressions. To overcome this problem, in this paper an attempt is made to develop a hybrid robust SAM-FC approach by combining rank of FC values and rank of p-values based on SAM statistic using minimum β-divergence method, which is designed for paired samples. This method introduces a weight function known as β-weight function. This weight function produces larger weights corresponding to usual/normal expressions and smaller weights for unusual/outlying expressions. The β-weight function plays the significant role on the performance of the proposed method. Results: The proposed method uses β-weight function as a measure of outlier detection by setting β=0.2. We unify both classical and robust estimates using β-weight function such that maximum likelihood estimators (MLEs) are used in absence of outliers and minimum β-divergence estimators are used in presence of outliers to obtain reasonable p-values and FC values in the proposed method. We examined the performance of proposed method in a comparison of some popular methods (t-test, SAM, LIMMA, Wilcoxon, WAD, RP and FCROS) using both simulated and real gene expression profiles for both small-and large-sample cases. From the simulation and a real spike in data analysis results we observed that the proposed method outperforms other methods for small-sample case in presence of outliers and it keeps almost equal performance with other robust methods (Wilcoxon, RP and FCROS) otherwise. From a head-and-neck cancer (HNC) dataset the proposed method identified 2 genes (CYP3A4, NOVA1) that are significantly enriched in linoleic acid metabolism, drug metabolism, steroid hormone biosynthesis and metabolic pathways. The survival analysis through Kaplan-Meier curve revealed that combined effect of these 2 genes has prognostic capability and they might be promising biomarker of HNC. Moreover, we retrieved the 12 candidate drugs based on gene interaction from glad4u and drug bank databases. Conclusion The identified drugs showed statistical significance and critical role of the proteins indicate that these proteins might be therapeutic target in cancer. Thus, elucidating the associations between the drugs identified in the present study require further investigations.
ARTICLE | doi:10.20944/preprints202210.0023.v2
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: cooperation; conditioned media; TGF-β1; intratumour heterogeneity; metastasis; EMT; invasion
Online: 14 November 2022 (10:58:41 CET)
Intratumour heterogeneity is often associated with poor response to treatment and bad prognosis. In addition to constitutive genetic/epigenetic sources, phenotypic and functional heterogeneity can reflect cell plasticity due to changes in gene expression patterns induced by signals from the tumour microenvironment or other cells. Positive interactions between cancer clones can increase their fitness and contribute to tumour growth, resistance to drugs and metastasis. Consequently, understanding the pathways involved in such behaviours is of great significance for cancer treatment. To explore if and how genetically distant clones can synergistically enhance each other's metastatic potential, this study used three (two breast and one lung) cancer cell lines with different aggressiveness levels. We found that (i) the conditioned media from the breast and lung aggressive lines induce mesenchymal features and increase the migration and invasion potential of the poorly metastatic breast line, and (ii) in both cases, this interclonal communication is based on the same soluble factor – namely, the tumour growth factor TGF-β1. Furthermore, when the two breast lines are mixed and co-cultured, the invasive potential of both lines is enhanced, and this outcome is dependent on the recruitment of the less aggressive clone into expressing a malignant phenotype. Based on our findings, we propose a two-tier model whereby highly metastatic clones can recruit weakly metastatic clones into acquiring an invasive phenotype, which in turn augments the invasion ability of the former (i.e., a “help me help you” strategy) through shared proteases and/or ECM remodelling. We suggest that such synergistic cooperation can easily emerge via cross-talk involving metastatic clones able to constitutively secrete signalling molecules that induce and maintain their own malignant state (i.e., autocrine/cell-autonomous signalling) and clones that have the ability to respond to those signals (i.e., paracrine/non-cell-autonomous signalling) and express a metastatic phenotype. Taking into account the lack of therapies to directly affect the metastatic process, interfering with such cooperative behaviours that tumour cells engage in during the early steps in the metastatic cascade could provide an additional strategy to increase patient survival.
ARTICLE | doi:10.20944/preprints202106.0192.v1
Online: 7 June 2021 (15:32:43 CEST)
Pseudomonas aeruginosa is an adaptable bacterial pathogen that infects various organs, including the respiratory tract, vascular system, urinary tract, and central nervous system leading to high morbidity and mortality. Our primary focus of this study was to characterize P. aeruginosa clinical strains on the basis of pigment color production, determine its association to multidrug resistance behavior and ability to form biofilm. We identified yellow (30.1%), green (39.8%) and no pigment (30.1%) producing strains from a total of 143 clinical isolates. Yellow pigment producing strains presented significant resistance to a class of antibiotics including β-lactam (91.5%), aminoglycosides (70.5%), and carbapenems (51.9%) compared to green and non-pigmented strains. Importantly, 16.3% of yellow pigment producing strains was resistant to colistin where only 2.3% of non-pigmented and 1.8% of green pigmented strains were resistant to this agent. Moreover, yellow pigment producing strain were frequent producers of β-lactamase group of enzymes, ESBL (55.6%), MBL (55.6%), and AmpC (50%) and displayed higher frequency of efflux positive group (64.2%) compared to green (7.14%) and non-pigmented one (28.5%). Notably, green pigment producing strains when compared to non-pigmented groups also displayed antibiotic susceptibility behavior similar to yellow pigment producing strains. Although yellow pigment producing strains were strong biofilm producers, no significant association was identified between pigment and biofilm formation. Among pigmented and non-pigmented strains, majority of yellow pigment producing strains have shown MIC levels greater than the green and non-pigmented strains. Our study has demonstrated the impact of pigment coloration on susceptibility to antimicrobial agents where yellow pigment producing strains represent considerably a serious problem as due to lack of alternative agents against such transformed strain may collectively be associated with multidrug resistance development.
ARTICLE | doi:10.20944/preprints202103.0426.v1
Subject: Life Sciences, Biochemistry Keywords: amyloid β-peptide; oligomerization; aggregation; FRET
Online: 16 March 2021 (13:29:35 CET)
Amyloid β-peptide (Aβ) oligomerization is believed to contribute to the neuronal dysfunction in Alzheimer disease (AD). Despite decades of research, many details of Aβ oligomerization in neurons still need to be revealed. Förster Resonance Energy Transfer (FRET) is a simple but effective way to study molecular interactions. Here we use a confocal microscope with a sensitive Airyscan detector for FRET detection. By live cell FRET imaging, we detect Aβ42 oligomerization in primary neurons. The neurons were incubated with fluorescently labelled Aβ42 in the cell culture medium for 24 hours. Aβ42 were internalized and oligomerized into the lysosomes/late endosomes in a concentration-dependent manner. Both the cellular uptake and intracellular oligomerization of Aβ42 were significantly higher than for Aβ40. These findings provide a better understanding of Aβ42 oligomerization in neurons.
REVIEW | doi:10.20944/preprints202012.0250.v1
Online: 10 December 2020 (11:30:57 CET)
β-glucan is a generic term for insoluble dietary fibers exerting various effects on the immune system. As a group, β-glucans are non-cellulose polysaccharides composed of a glucopyranose as the main constituent sugar with β configuration, having a β- (1,3)-linked glucopyranose main chain as a common feature. β-glucans are absorbed through the intestine. Since the 1980s, there have been many studies reporting various effects of β-glucans on the immune system, including reports on receptors, that have slowly clarified their recognition system and action mechanisms. However, these studies focused mostly on treatments of infectious diseases and tumors; thus, the effects of β-glucans ingested in food as dietary fiber and their mechanisms of action remain largely unknown. The uptake of β-glucan into the body may be resemble that of proteins, which are soluble polymers, and insoluble material such as dietary fiber. Dietary fibers have varied structures, with wide-ranging solubility and physiological effects. Understanding whether these substances are actually taken up, how they exert their effects, and their metabolism after being taken up are important issues when considering the functionality and safety of dietary fibers.
ARTICLE | doi:10.20944/preprints202010.0025.v1
Online: 1 October 2020 (16:46:42 CEST)
The objective of this study was to evaluate the effects of dietary supplementation with bacteriophage and β-mannanase on health and growth performance in calves. Thirty-six pre-weaning male Holstein calves were randomly allocated to one of four dietary treatments: no supplementation, 0.1% β-mannanase, 0.1% bacteriophage, and both 0.1% bacteriophage and β-mannanase supplementation in a starter. The experiment lasted from 2 weeks before weaning to 8 weeks after weaning. Twenty-two calves survived to the end of the experiment. No interaction was observed between the two methods of supplementation. A 1-kg increase in initial BW resulted in a 1.41-fold increase in the odds ratio of survival (p < 0.01). The bacteriophage supplementation tended to increase the odds ratio of survival (p = 0.09). The number of Escherichia coli in feces significantly decreased one week after weaning. β-mannanase supplementation increased the concentrates intake (p < 0.01) and tended to increase the final BW (p = 0.08). Analysis of repeated measures indicated β-mannanase supplementation increased weekly body weight gain (p = 0.018). We conclude that bacteriophage supplementation may have a positive effect on calf survival rate, while β-mannanase supplementation may increase the growth rate and intake of a starter in calves.
REVIEW | doi:10.20944/preprints202007.0589.v1
Online: 24 July 2020 (13:59:24 CEST)
The probability of the evolution of a character depends on two factors: the probability of moving from one character state to another character state and the probability of the new character state fixation. More the evolution of a character is probable more convergent evolution will be witnessed, consequently, convergent evolution could mean that the convergent character evolution result as a combination of these two factors. We investigate this phenomenon by studying the convergent evolution of biochemical functions. We use for the investigation the case of β-lactamases. β-lactamases hydrolyzes β-lactams which are antimicrobials able to block the DD-peptidases involved in bacterial cell wall synthesis. β-lactamase activity is present in two different superfamilies: the metallo-β-lactamase and the serine β-lactamase superfamily. The mechanism used to hydrolyze the β-lactam is different for the two superfamilies. We named this kind of evolution an allo-convergent evolution. We further show that the β-lactamase activity evolved several times within each superfamily, a convergent evolution type that we named iso-convergent evolution. Both types of convergent evolution can be explained by the two evolutionary mechanisms discussed above. The probability of moving from one state to another is explaining the promiscuous β-lactamase activity present in the ancestral sequences of each superfamily, while the probability of fixation is explained in part, by positive selection as the organisms having β-lactamase activity allows them to resist to organism secreting β-lactams. Indeed a mutation increasing the β-lactamases activity will be selected as the organisms having this activity will have an advantage over the others.
ARTICLE | doi:10.20944/preprints202003.0244.v1
Subject: Chemistry, Organic Chemistry Keywords: antibiotics; β cells; streptozotocin; regioselective oxidation
Online: 15 March 2020 (13:12:33 CET)
With the increasing resistance of bacteria to current antibiotics, novel compounds are urgently needed to treat bacterial infections. Streptozotocin (STZ) is a natural product that has broad-spectrum antibiotic activity, albeit with limited use because of its toxicity to pancreatic β cells. In an attempt to derivatize STZ through structural modification at the C3 position, we performed the synthesis of three novel STZ analogues by making use of our recently developed regioselective oxidation protocol. Keto-STZ (2) shows the highest inhibition of bacterial growth (MIC and viability assays), but is also the most cytotoxic compound. Pre-sensitizing the bacteria with GlcNAc increased the antimicrobial effect, but did not result in complete killing. Interestingly, allo-STZ (3) revealed moderate concentration-dependent antimicrobial activity and no cytotoxicity towards β cells, and deoxy-STZ (4) showed no activity at all.
ARTICLE | doi:10.20944/preprints201809.0496.v1
Subject: Materials Science, Nanotechnology Keywords: HDPAF; β-carotene; electrospraying; encapsulation; photoprotection
Online: 26 September 2018 (04:38:54 CEST)
High degree of polymerisation agave fructans (HDPAF) are presented as a novel encapsulating material. Electrospraying coating (EC) was selected as the encapsulation technique and β-carotene as the model bioactive compound. In case of direct electrospraying, two encapsulation methodologies (solution and emulsion) were proposed to find the formulation which provided a suitable particle morphology and an adequate concentration of β-carotene encapsulated in the particles. SEM images showed spherical particles with sizes ranging from 440 to 880 nm depending on the concentration of HDPAF and processing parameters. FTIR analysis confirmed interaction and encapsulation of β-carotene with HDPAF. Thermal stability of β-carotene encapsulated in HDPAF was evidenced by thermogravimetric analysis (TGA). The study showed that β-carotene encapsulated in HDPAF by the EC method remained stable for up to 50 h of exposure to UV light. Therefore, HDPAF is a viable option to formulate nanocapsules as a new encapsulating material. In addition, EC allowed increasing the ratio β-carotene:polymer as well as its photostability.
ARTICLE | doi:10.20944/preprints201711.0005.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: cardamom; supercritical CO2 extraction; β-sitosterol
Online: 1 November 2017 (04:54:35 CET)
Cardamom is plant of the Zingiberaceae family. It has been used for the treatment of many diseases such as migraine, bronchitis, stomach and intestinal disorders. Cardamom contains triterpenes, resins, starch and fatty compounds. Phytosterols (stigmasterol, campesterol and β-sitosterol) are a group steroid alcohol in plants. They are used food, medicine and cosmetic industry. They are protective effects against some types of cancer too. Phytosterols are found in the vegetable oil such as the spindle, corn and soybean oil. This paper deals with the maximum oil and β-sitosterol yield were investigated by means of the supercritical CO2 extraction of cardamom. The effect of operating parameters as temperature, pressure and CO2 flow rate were investigated on oil yield. The amount of β-sitosterol was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) at optimized conditions. The optimized conditions were recorded as temperature of 40oC, pressure of 200 bar and CO2 flow rate of 4 L/min. The maximum oil yield and amount of β-sitosterol were found as 74.83 mg oil/g seed and 4.73 mg β-sitosterol/g seed cardamom under these conditions.
COMMUNICATION | doi:10.20944/preprints201612.0122.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: furfuryl alcohol; β- myrcene; carcinogens; occurrence
Online: 25 December 2016 (08:21:19 CET)
For decades, compounds present in foods and beverages have been implicated in the etiology of human cancers. The International Agency for Research on Cancer (IARC) continues to classify such agents regarding their potential carcinogenicity in humans based on new evidence from animal and human studies. Furfuryl alcohol and β-myrcene belong to these potential human carcinogens due to be evaluated. The major source of furfuryl alcohol in foods is thermal processing and ageing of alcoholic beverages while β-myrcene occurs naturally as a constituent of essential oils of plants such as hops, lemongrass and derived products. This study aimed to summarize the occurrence of furfuryl alcohol and β-myrcene in foods and beverages using data from own nuclear magnetic resonance (NMR) analysis and literature review. The highest content of furfuryl alcohol was found in coffee beans (>100 mg/kg) and in some fish products (about 10 mg/kg) while among beverages, wines contained between 1–10 mg/L with 8 mg/L in pineapple juice. The content of β-myrcene was highest in hops. In conclusion, the data about the occurrence of the two agents is either very old or based on single sample analysis, and currently judged as insufficient for exposure and risk assessment. The results of this study point out the food and beverage groups that may be considered for future monitoring of furfuryl alcohol and β-myrcene.
ARTICLE | doi:10.20944/preprints202210.0046.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: cancer; circulating tumour cell clusters; metastasis; TGF-β1; extravasation; phenotypic plasticity
Online: 5 October 2022 (16:35:01 CEST)
Metastasis – the ability of cancer cells to disperse and colonize distant locations in the body, is responsible for the majority of cancer-related deaths. While in the vasculature, tumour cells are referred to as circulating tumour cells (CTCs) and can manifest either as single cells or clusters of cells, with the latter being the most aggressive. Despite their significant role in the metastatic process, the mechanisms through which CTC clusters extravasate and disseminate remain largely unknown. Notably, CTC clusters have been found to contain platelets, which are known to secrete many factors, including Transforming Growth Factor Beta 1 (TGF-β1) – a signaling molecule that has been widely implicated in many aspects of cancer, including the extravasation of single CTCs. To address whether the interaction between platelets and CTC clusters might also facilitate the extravasation of CTC clusters, we evaluated the effect of exogenous TGF-β1 on an experimentally evolved lung cancer cell line that grows as cell clusters that we previously developed and used to investigate the biology of CTC clusters. We found that exogenous TGFβ1 induces the dissociation of clusters and cell adherence. Furthermore, once adhered, cells release their own TGF-β1 and are able to migrate and invade in the absence of exogenous TGFβ1. Based on these findings we propose a model that involves both paracrine and autocrine TGFβ1-mediated phenotypic plasticity resulting in the acquisition of traits that enable the extravasation of CTC clusters as single cells.
ARTICLE | doi:10.20944/preprints201809.0133.v1
Subject: Medicine & Pharmacology, Gastroenterology Keywords: cell migration; hepatic stellate cell; TGF-β1; Rap1; RhoA; NF-κB
Online: 7 September 2018 (12:19:49 CEST)
Although the migration of hepatic stellate cells (HSCs) is important for hepatic fibrosis, the regulation of HSC migration is poorly understood. Interestingly, transforming growth factor (TGF)-β1 induces monocyte migration to sites of injury or inflammation in the early phase but inhibits cell migration in the late phase. In this study, we investigated the role of RhoA signaling in TGF-β1-induced HSC migration. We found that TGF-β1 increased the protein and mRNA levels of α-SMA and collagen type I in HSC-T6 cells. The level of RhoA-GTP in TGF-β1-stimulated cells was significantly higher than that in control cells. Moreover, cofilin phosphorylation and F-actin formation was more strongly detected in TGF-β1-stimulated cells than in control cells. Additionally, TGF-β1 induced the activation of NF-κB and the expression of extracellular matrix proteins and several cytokines in HSC-T6 cells. The active form of Rap1 (Rap1 V12) suppressed RhoA-GTP levels, whereas the dominant negative form of Rap1 (Rap1 N17) augmented RhoA-GTP levels. Therefore, we confirmed that Rap1 regulates RhoA activation in TGF-β1-stimulated HSC-T6 cells. These findings suggest that TGF-β1 regulates Rap1, resulting in RhoA suppression, NF-κB activation and F-actin formation during the migration of HSCs.
REVIEW | doi:10.20944/preprints202005.0334.v1
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: Human Bregs; IL-10; IL-35; TGF- ß; myasthenia gravis; Bregs expansion
Online: 21 May 2020 (03:55:17 CEST)
Regulatory B cells (Bregs) with immunosuppressive function are critical in maintaining immune tolerance. In recent years, Bregs is an essential part of the study due to its therapeutic relevance and function in immune tolerance. The positive and negative regulatory role of human Bregs in immune tolerance is being discussed in several pathologies, including in autoimmune diseases, cancers, chronic infections, strokes in multiple reports. The negative regulatory roles of human Bregs are associated with lesser numbers and functional abnormalities in most of these studies, including myasthenia gravis (MG). In this review, the potential findings regarding human Bregs in MG, and Bregs mediated potential therapeutic strategies with its pros and cons have been discussed based on previous and current reports.
ARTICLE | doi:10.20944/preprints201812.0131.v1
Subject: Medicine & Pharmacology, Psychiatry & Mental Health Studies Keywords: Major depressive disorder (MDD), ketoprofen, TGF-β1, INF-γ, IDO, immune, inflammation
Online: 11 December 2018 (13:52:50 CET)
Major Depression Disorder (MDD) is accompanied by an immune response characterized by increased levels of pro-inflammatory and immune-regulatory cytokines and cytokine-induced stimulation of indoleamine-2,3-dioxygenase (IDO). There is also some evidence that anti-inflammatory drugs may have a clinical efficacy in MDD.The aim of this study is to examine the clinical effects of an eight-week combinatorial treatment of ketoprofen (a nonsteroidal anti-inflammatory drug) combined or not with sertraline, on serum levels of IDO, interferon (IFN)-γ, interleukin (IL)-4 and transforming growth factor (TGF)-β1 in association with changes in the Beck-Depression Inventory-II (BDI-II). The study included 140 MDD patients and 40 normal controls. The pre-treatment serum levels of IDO, IFN-γ, TGF-β1 and IL-4 were significantly higher in MDD patients compared with the control group. Treatment with sertraline with or without ketoprofen significantly reduced the increased baseline production of all 4 biomarkers to levels which were similar as those of normal controls. Ketoprofen add-on had a significantly greater effect on IDO and BDI-II as compared with placebo. The reductions in IDO, IL-4 and TGF-β1 during treatment were significantly associated with those in the BDI-II.In conclusion, the clinical efficacy of both sertraline + ketoprofen may be ascribed at least in part to attenuated IDO levels and immune-inflammatory responses in MDD. Moreover, add-on treatment with ketoprofen may augment the efficacy of sertraline by attenuating IDO. However, these treatments may also significantly reduce the more beneficial properties of T helper-2 and T regulatory (Treg) immune subsets. Future research should develop immune treatments that target the immune-inflammatory response in MDD, while enhancing the compensatory immune-regulatory system (CIRS).
ARTICLE | doi:10.20944/preprints202012.0354.v1
Subject: Medicine & Pharmacology, Allergology Keywords: meprin α; meprin β; zinc metalloproteinase; uHTS
Online: 14 December 2020 (16:36:57 CET)
Meprin α and β are zinc-dependent proteinases implicated in multiple diseases including cancers, fibrosis, and Alzheimer’s. However, until recently, only a few inhibitors of either meprin were reported and no inhibitors are in pre-clinical development. Moreover, inhibitors of other metzincins developed in previous years are not effective in inhibiting meprins suggesting the need for de novo discovery effort. To address the paucity of tractable meprin inhibitors we developed ultra-high throughput assays and conducted parallel screening of >650,000 compounds against each meprin. As a result of this effort, we identified 5 selective meprin α hits belonging to three different chemotypes (triazole-hydroxyacetamides, sulfonamide-hydroxypropanamides, and phenoxy-hydroxyacetamides). These hits demonstrated a nanomolar to micromolar inhibitory activity against meprin α with low cytotoxicity and >30-fold selectivity against meprin β and other related metzincincs. These are the most selective inhibitors of meprin α to date.
ARTICLE | doi:10.20944/preprints202011.0597.v1
Subject: Life Sciences, Biochemistry Keywords: Arylsulfatase; β-glucuronidase; Hydrogen peroxide; Hypochlorite; Inhibition
Online: 23 November 2020 (19:22:12 CET)
Arylsulfatase and β-glucuronidase are two important enzymes in human, which play important role on dynamic equilibrium of steroidal estrogens. This work probably for the first time reported that hydrogen peroxide (H2O2), hypochlorite and peracetic acid (PAA) could effectively inhibit the activities of arylsulfatase and/or β-glucuronidase. The 50 percent of inhibitions (IC50) of H2O2, and PAA on arylsulfatase were found to be 142.90±9.00, 91.83±10.01, and 43.46±2.92 μM, respectively. The corresponding respective IC50 of hypochlorite and PAA on β-glucuronidase were 704.90±41.40 and 23.26±0.82 μM, while H2O2 showed no inhibition on β-glucuronidase. It was further revealed that the inhibition of hypochlorite on both arylsulfatase and β-glucuronidase was irreversible. On the contrary, the inhibition by H2O2 and PAA was reversible. Moreover, it was found that the inhibitions of arylsulfatase and/or β-glucuronidase by these three chemicals were pH-dependent, among which the inhibition by H2O2 was competitive and non-competitive for PAA. In general, H2O2 and hypochlorite can be endogenously produced in human, which suggested that the two compounds are potential endocrine disruption compounds (EDCs) as they can cause endocrine disruption via inhibition of arylsulfatase and β-glucuronidase. This work further indicated that any agent that can induce production of H2O2 or hypochlorite in human is potential EDC, which explains why some EDCs with very weak or no estrogenic potency can cause endocrine disruption that confirmed in epidemiological studies.
ARTICLE | doi:10.20944/preprints201810.0207.v1
Online: 10 October 2018 (07:42:31 CEST)
SAA is an acute phase protein that elevates under inflammatory circumstance. The serum level of SAA was associated with the progression of inflammation in numerous diseases. However, little attention was paid to the correlation between SAA and ONFH. In this study, SAA was found risen in the femoral head of osteonecrosis patients through proteomics analysis and further confirmed by ELISA. Furthermore, SAA was proven affecting bone metabolism in rBMSCs. It facilitated the proliferation of rBMSCs whereas it suppressed the osteogenic differentiation of rBMSCs and accelerated the adipogenic differentiation of rBMSCs. Thus, we deem that serum amyloid A, which is a vital acute phase protein in inflammation, affected bone metabolis and plays an imperative role in the pathophysiological process of ONFH.
Subject: Chemistry, Other Keywords: bioactive compounds from European trees and shrubs; gallic and cinnamic acids; quercetin; pinosylvin; β–sitosterol; alfa- and β-pinene
Online: 28 October 2019 (11:57:17 CET)
Plants produce specific structures constituting a barrier hindering penetration of pathogens, while they also produce substances inhibiting pathogen growth . These compounds are secondary metabolites, such as phenolics, terpenoids, sesquiterpenoids, resins, tannins and alkaloids. Bioactive compounds are secendary metabolities from trees and shrubs are used in medicine, herbal medicine and cosmetology. To date fruits and flowers of exotic trees and shrubs have been primarily used as sources of bioactive compounds. In turn, search for new sources of bioactive compounds is currently focused on native plant species due to its availability. Application of such raw material needs to be based on knowledge of their chemical composition, particularly health-promoting or therapeutic compounds. Research conducted to date on European trees and shrubs has been scarce. This paper presents results of literature studies conducted to systematise knowledge on bioactive compounds found in trees and shrubs native to central Europe. The aim of this review providing available information on the subject is to indicate gaps in the present knowledge.
Subject: Biology, Plant Sciences Keywords: 9-cis β-carotene; all-trans β-carotene; Dunaliella salina; red LED; blue LED; growth; light intensity; carotenoids; isomerisation
Online: 17 May 2019 (08:25:02 CEST)
Dunaliella salina is a rich source of 9-cis β-carotene, which has been identified as important in the treatment of retinal dystrophies and other diseases. We previously showed that chlorophyll absorption of red light photons in D. salina is coupled to oxygen reduction and phytoene desaturation and increases the pool size of β-carotene . Here we show for the first time that growth under red light also controls conversion of extant all-trans β-carotene to 9-cis β-carotene by β-carotene isomerases. Cells illuminated with red light from a light emitting diode (LED) during cultivation contained a higher 9-cis β-carotene content compared to cells illuminated with white or blue LED light. The 9-cis/all-trans β-carotene ratio in red light treated cultures reached >2.5:1 within 48 hours and was independent of light intensity. Illumination using red light filters that eliminated blue wavelength light also increased the 9-cis/all-trans β-carotene ratio. With norflurazon, a phytoene desaturase inhibitor which blocked downstream biosynthesis of β-carotene, extant all-trans β-carotene was converted to 9-cis β-carotene during growth with red light and the 9-cis/all-trans β-carotene ratio was ~2:1. With blue light under the same conditions, 9-cis β-carotene was likely destroyed at a greater rate than all-trans β-carotene (9-cis/all-trans ratio 0.5:1). Red light perception by the red light photoreceptor, phytochrome, may increase the pool size of anti-oxidant, specifically 9-cis β-carotene, both by upregulating phytoene synthase to increase the rate of biosynthesis of β-carotene and to reduce the rate of formation of reactive oxygen species (ROS), and by upregulating β-carotene isomerases to convert extant all-trans β-carotene to 9-cis β-carotene.
Subject: Medicine & Pharmacology, Allergology Keywords: cardiac fibroblasts; WNT3a; WNT5a; beta-catenin; TGF-beta signalling; IL-11; cardiac fibrosis
Online: 29 July 2021 (13:15:00 CEST)
Cardiac fibrosis is a pathological process associated with development of heart failure. TGF-β and WNT signaling have been implicated in pathogenesis of cardiac fibrosis, however little is known about molecular cross-talk between these two pathways. The aim of this study was to examine the effect of exogenous canonical WNT3a and non-canonical WNT5a in TGF-β-activated human cardiac fibroblasts. We found that WNT3a and TGF-β induced -catenin-dependent response, whereas WNT5a prompted AP-1 activity. TGF-β triggered profibrotic signature in cardiac fibroblasts, and co-stimulation with WNT3a or co-activation of the β-catenin pathway with GSK3β inhibitor CHIR99021 enhanced collagen I and fibronectin production and development of active contractile stress fibers. In the absence of TGF-β, neither WNT3a nor CHIR99021 exerted profibrotic response. On a molecular level, in TGF-β-activated fibroblasts WNT3a enhanced phosphorylation of TAK1 and production and secretion of IL-11 but showed no effect on Smad pathway. Neutralization of IL-11 activity with the blocking anti-IL-11 antibody effectively reduced profibrotic response of cardiac fibroblasts activated with TGF-β and WNT3a. In contrast to canonical WNT3a, co-activation with non-canonical WNT5a suppressed TGF-β-induced production of collagen I. In conclusion, WNT/β-catenin signaling promotes TGF-β-mediated fibroblast-to-myofibroblast transition by enhancing IL-11 production. Thus, the uncovered mechanism broadens our knowledge on molecular basis of cardiac fibrogenesis and defines novel therapeutic targets for fibrotic heart diseases.
ARTICLE | doi:10.20944/preprints202103.0387.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: β-cyclodextrin; binary complex; antipsychotic drug; dissolution studies
Online: 15 March 2021 (13:44:03 CET)
Iloperidone (ILO) is a second-generation antipsychotic drug and a first-line treatment approved by USFDA in May 2009. Iloperidone belongs to Biopharmaceutical Classification Systems (BCS) class II; thus, it is poorly water-soluble, highly permeable, and has pH-dependent solubility. Cyclodextrins and their derivatives have a wide range of applications in different formulations due to their complexation ability, which improves the solubility, stability, safety, and bioavailability of a drug. We have tried the complexation of iloperidone with sulfobutyl ether-β-cyclodextrin (SEβCD) to improve its solubility and dissolution. Complexation was done by the kneading method. The characterization of the SEβCD complexes with Iloperidone was done by FTIR, differential scanning calorimetry (DSC), saturation solubility, etc. A multimedia dissolution of the complex was carried out and compared with the plain drug. A significant improvement in drug release was found from SEβCD complexes in all media when compared with the drug alone.
ARTICLE | doi:10.20944/preprints202008.0610.v1
Online: 27 August 2020 (10:32:16 CEST)
Signaling through GPR109a, the putative receptor for the endogenous ligand β-OH butyrate, inhibits adipose tissue lipolysis. Niacin, an anti-atherosclerotic drug that can induce insulin resistance, activates GPR109a at nM concentrations. GPR109a is not essential for niacin to improve serum lipid profiles. To better understand the involvement of GPR109a signaling in regulating glucose and lipid metabolism, we treated GPR109a wildtype (+/+) and knockout (-/-) mice with repeated overnight injections of saline or niacin in physiological states characterized by low (ad libitum fed) or high (16h fasted) concentrations of the endogenous ligand, β-OH butyrate. In the fed state, niacin increased expression of PEPCK mRNA independent of genotype, while increasing CPT1 mRNA only in GPR109a -/- mice. Niacin decreased fasting serum non-esterified fatty acid concentrations in both GPR109a +/+ and -/- mice. Independent of GPR109a expression, niacin blunted fast-induced hepatic triglyceride accumulation and peroxisome proliferator activated receptor α (PPARα) mRNA expression. Surprisingly, GPR109a knockout did not affect glucose or lipid homeostasis or hepatic gene expression in either fed or fasted mice. In turn, GPR109a does not appear to be essential for the metabolic response to the ketogenic state or the pharmacological benefits associated with niacin.
ARTICLE | doi:10.20944/preprints201706.0072.v1
Subject: Life Sciences, Molecular Biology Keywords: Specnvezhenide; osteoarthritis; chondrocyte; NF-κB; wnt/β-catenin
Online: 16 June 2017 (04:20:07 CEST)
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.
ARTICLE | doi:10.20944/preprints201703.0047.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: 17 β-estradiol; estrogen pollution; female reproduction; DPV
Online: 8 March 2017 (05:39:59 CET)
Environmental estrogen pollution and estrogen effects on the female reproduction system are well-recognized scientifically. Among the estrogens, 17 β-estradiol is a priority in environmental estrogen pollution, and it is also a major contributor to estrogen which regulates the female reproduction system. 17 β-estradiol is carcinogen and has a tumor promotion effect relating to breast cancer, lung cancer and others. It also affects the psychological well-being such as depression, fatigue and others. Thus, a simple method of detection of 17 β-estradiol will be important for both environmental estrogen pollution and women’s health care. This study demonstrates a simple-use, cost effective 17 β-estradiol biosensor system which can be used for both environment and women’s health care applications. The bio-recognition mechanism is based on the influence of the redox couple, K3Fe (CN) 6/K4Fe (CN) 6 by the interaction between 17 β-estradiol antigen and its α-receptor (ER- α; α-estrogen antibody). The transduction mechanism is an electrochemical analytical technique, differential pulse voltammetry (DPV). The levels of 17 β-estradiol antigen studied was between 2.25 pg/mL to 2,250 pg/mL, Phosphate buffered saline (PBS), tap water from the Cleveland regional water district, and simulate urine were used as the test media covering the potential application areas for 17 β-estradiol detection. An interference study by testosterone which has a similar chemical structure and molecular weight as those of 17 β-estradiol was carried out, and this 17 β-estradiol biosensor showed excellent specificity without any interference by similar chemicals.
ARTICLE | doi:10.20944/preprints202205.0346.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: β-adrenoceptor; diabetes; empagliflozin; heart; pressure-volume loop analysis
Online: 25 May 2022 (09:59:26 CEST)
Diabetes mellitus leads to cardiovascular complications including impaired cardiac β-adrenoceptor (β-AR) function. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, such as empagliflozin (EMPA) improve outcomes in heart failure patients and animal models thereof. Therefore, we have investigated the effects of EMPA on in vivo cardiac function (pressure-volume loop analysis) and β-AR-mediated contractile responses (papillary strips) in streptozotocin (STZ; 40 mg/kg, i.p.)-induced diabes in male Sprague Dawley rats (control, EMPA-treated control, diabetic, EMPA-treated diabetic) in a design reflecting late-onset treatment. 13-16 weeks after STZ injection treatment with a low dose of EMPA (10 mg/kg/day, daily oral gavage) or vehicle was administered for another 8 weeks. EMPA did not change cardiac function in control rats. Diabetic rats had a reduced heart rate, cardiac output, stroke work, rate of contration and rate of relaxation and increased isovolumic relaxation, whereas in vitro responses were not markedly attenuated. Treatment with EMPA showed a trend for improvement of some but not all parameters. Our results indicate that low dose EMPA treatment had limited effects on cardiac impairment despite reducing blood glucose when initiated after diabetes is manifest. Future studies with a higher dose and greater sample sizes could help to clarify the possible benefits of EMPA on the diabetic heart.
ARTICLE | doi:10.20944/preprints202111.0366.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: β-Apopicropodophyllin; Radiosensitizer; Topoisomerase inhibitor; ROS, Apoptosis; Colorectal cancer
Online: 19 November 2021 (14:54:40 CET)
β-apopicropodophyllin (APP), a derivative of podophyllotoxin (PPT), has been identified as a potential anti-cancer drug. This study tested whether APP acts as an an-ti-cancer drug and can sensitize colorectal cancer (CRC) cells to radiation treatment. APP had an anti-cancer effect against the CRC cell lines HCT116, and DLD-1, SW480 and COLO320DM with IC50 values of 7.88 nM, and 8.22 nM, 9.84 nM and 7.757 nM, respec-tively induction of DNA damage. Colonogenic and cell counting assays indicated that the combined treatment of APP and γ-ionizing radiation (IR) showed greater retardation of cell growth than either alone, suggesting that APP sensitizes CRC cells to IR. Annexin V-propidium iodide (PI) assays and immunoblot analysis showed that the combined treatment of APP and IR increased apoptosis in CRC cells compared with either APP or IR alone. Results obtained from the xenograft experiments also indicated that the combination of APP and IR enhanced apoptosis in in vivo animal model. Apoptosis induction by the combined treatment of APP and IR resulted from reactive oxygen species (ROS). Inhibition of ROS by N-acetylcysteine (NAC) restored cell viability and decreased the induction of apoptosis by APP and IR in CRC cells. Taken together, these results indicate that a combined treatment of APP and IR might promote apoptosis by inducing ROS in CRC cells.
REVIEW | doi:10.20944/preprints202109.0341.v1
Subject: Life Sciences, Other Keywords: Edible Mushrooms; anti-cancerous; bioactive compounds; therapeutic; β-glucan
Online: 20 September 2021 (15:33:47 CEST)
Mushrooms have been an invaluable ingredient in terms of food and medicine to humanity since time immemorial. Mushrooms have been shown to be possessing properties such as anti-tumor, antiproliferative, antioxidant, immunomodulatory, anti-diabetic. Traditional Czech republic medicine involved using Piptoporus betulinus in curing colorectal cancer; similarly, fruiting bodies of Inonotus obliquus were employed in Folk medicine in eastern Europe since the 16th century. The oriental practice of utilizing mushrooms has witnessed an overwhelming attentiveness from the global research fraternity in exploring its wonder substances. Cancer is one of the key problems faced by researchers in finding an efficient medicine without inducing severe health complications. Mushrooms contain a plethora of bioactive compounds involved in tumor inhibition, such as hispolon, lentinan, gannoderic acid, illudin-s, and many more. The current article briefly describes various edible mushrooms with anti-tumorigenic compounds and their effect on the cancer cells of various means.
Subject: Medicine & Pharmacology, Nutrition Keywords: Alzheimer’s disease; lactoferrin; cognitive function; gut microbiota; amyloid β
Online: 17 February 2020 (01:00:26 CET)
Existing evidence suggest that lactoferrin might be beneficial for Alzheimer’s disease. We aimed to determine the effects of lactoferrin intervention on cognitive function from APP/PS1 mice, and possible mechanisms involved in. Both young and middle-aged male APP/PS1 mice were divided into control and lactoferrin group with 16 weeks’ intervention. Lactoferrin intervention had no effects on cognitive function from both young and middle-aged mice, and no key markers involved in Aβ, tau pathology, neuro-inflammation and synaptic plasticity were altered post lactoferrin intervention. In regards to gut microbiota profiles, in the young mice, lactoferrin elevated α diversity index including ACE and Chao 1, and reduced the relative abundance of the genera Bacteroides and Alistipes and elevated Oscillibacter, in addition, Oscillibacter, Anaerotruncus, EF096579_g, EU454405_g, Mollicutes_RF39, EU474361_g, EU774448_g, and EF096976_g were specifically abundant post Lf intervention via LEfSe analysis. In the middle-aged mice, the relative abundance of the phylum Proteobacteria, as well as the genera Oscillospira, Coprococcus and Ruminococcus was significantly reduced post Lf intervention, additionally, S24_7, Bacteroidia, Bacteroidetes and Methylobacterium were specific via LEfSe analysis post lactoferrin intervention. In conclusion, dietary lactoferrin might be beneficial for gut microbiota homeostasis although might have no effects on cognition.
ARTICLE | doi:10.20944/preprints201910.0272.v1
Subject: Biology, Plant Sciences Keywords: durum wheat; β-carotene; TILLING; biofortification; vitamin A deficiency
Online: 24 October 2019 (05:28:00 CEST)
Macro and micronutrients, essential for the maintenance of human metabolism, are daily assimilated through the diet. Wheat and other major cereals are a good source of nutrients, such as carbohydrates and proteins, but cannot supply enough amounts of essential micronutrients which includes provitamin A. As vitamin A deficiency (VAD) lead to several serious diseases spread worldwide, the biofortification of a major staple crop, such as wheat, represents an effective way to preserve human health in developing countries. In the present work, a key enzyme involved in the branch of carotenoids pathway producing β-carotene, lycopene epsilon cyclase, has been targeted by a TILLING approach in a “Block strategy” perspective. The null mutant genotype showed a strong reduction in the expression of lcyE gene and also interesting pleiotropic effects on an enzyme (β-ring hydroxylase) acting downstream in the pathway. Biochemical profiling of carotenoids in the wheat mutant lines showed an increase of roughly 75% in β-carotene in the grains of the complete mutant line vs. the control. In conclusions, here we describe the production and the characterization of a new wheat line biofortified in provitamin A obtained through a non-transgenic approach also shading new light on the molecular mechanism governing carotenoids biosynthesis in durum wheat.
REVIEW | doi:10.20944/preprints201704.0135.v1
Subject: Life Sciences, Biochemistry Keywords: GPCR; ubiquitination; β-arrestin; deubiquitinating enzyme; E3 ubiquitin ligase
Online: 21 April 2017 (06:23:26 CEST)
G protein-coupled receptors (GPCRs) comprise the largest family of membrane receptors that control many cellular processes and consequently often serve as drug targets. These receptors undergo a strict regulation by mechanisms such as internalization and desensitization, which are strongly influenced by posttranslational modifications. Ubiquitination is a posttranslational modification with a broad range of functions that is currently gaining increased appreciation as a regulator of GPCR activity. The role of ubiquitination in directing GPCRs for lysosomal degradation has already been well-established. Furthermore, this modification can also play a role in targeting membrane and endoplasmic reticulum-associated receptors to the proteasome. Most recently, ubiquitination was also shown to be involved in GPCR signaling. In this review, we present current knowledge on the molecular basis of GPCR regulation by ubiquitination, and highlight the importance of E3 ubiquitin ligases, deubiquitinating enzymes and β-arrestins. Finally, we discuss classical and newly-discovered functions of ubiquitination in controlling GPCR activity.
ARTICLE | doi:10.20944/preprints201609.0037.v1
Subject: Biology, Plant Sciences Keywords: Consolida orientalis; ethyl acetate extract; antioxidant activity; β-sitosterol
Online: 9 September 2016 (11:18:02 CEST)
General phytochemical screening of the aerial parts of Consolida orientalis revealed the presence of steroids, terpenes, phenolic compounds, saponins, fatty acids, alkaloids. This study was conducted to investigate the bioactivities of extracts, isolation and identification the compounds from aerial parts of C.orientalis. The main goal of the present study is identifying and characterizing the antioxidant activity of the Consolida orientalis and biological isolation of active terpenoid. Aerial parts of the plant were dried at room temperature and reduced to small pieces, followed by using extraction with ethyl acetate percolation. Tree complementary analysis system was used, DPPH free radical scavenging test, total phenolic metabolites and FRAP. The total phenolic content was 38.83±2.09 mg gallic acid corresponding to g-1 extract with regarding to standard curve (y=0.0054x+0.0488, r2=0.995). IC50 value for DPPH radical – scavenging was 987.11±28.66 mgml-1. The extract was exhibited a medium reducing power compared with Vit C. The isolation and purification was afforded white crystalline powder which was subjected to physical, chemical and spectral identification by IR, 1H- and 13C- NMR and GC-MS. Isolated compound was identified as β-sitosterol. That is a terpenoid with melting point 133.4-134.5 ͦ c and with molecular formula C29H50O.
ARTICLE | doi:10.20944/preprints202301.0540.v1
Subject: Life Sciences, Microbiology Keywords: β -Lapachone; Bactericidal; Biofilms; Resistant; Zone of inhibition; Antimicrobial activity
Online: 30 January 2023 (06:10:49 CET)
Background: Bacterial infections constantly have a large impact on public health, because of increased rates of resistance and reduced frequency of development of novel antibiotics. The utility of conventional antibiotics for treating bacterial infections has become increasingly challenging. The aim of the study was to assess the antibacterial effect of β -Lapachone, a novel synthetic compound. Methods: The antibacterial activity of the β -Lapachone compound was examined against laboratory strains by agar well diffusion method, minimal inhibitory concentration (MICs), and minimal bactericidal concentration (MBCs). Growth kinetics inhibition in presence of β -Lapachone on Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa (ATCC 27853) was assessed by MABA. Crystal violet blue assay was used for biofilm inhibition assays, biofilm eradication assay and for molecular modeling PyMOL was used. Results: β -Lapachone exhibited potent antimicrobial activity against laboratory strains of bacteria with MIC of 0.2 mM for S. saprophyticus and Staphylococcus aureus, and 0.04 mM for Staphylococcus epidermidis and Pseudomonas aeruginosa ATCC 27853. The inhibition of catalase enzyme was found to be the cause for its antibacterial activity. Molecular modeling predicted the binding of β -Lap at active site and heme binding site of catalase, KatA. The activity of some commercial antibiotics was enhanced in association with β -Lap. In addition, β -Lap inhibited the biofilm formation and eradicated the already formed and ultra-mature biofilms of aforesaid bacterial strains.
ARTICLE | doi:10.20944/preprints202301.0350.v1
Subject: Life Sciences, Microbiology Keywords: whole genome sequencing; β-lactamases; MLST; plasmid replicons; Klebsiella pneumoniae
Online: 19 January 2023 (09:06:46 CET)
Klebsiella pneumoniae (Kp) has gained prominence in the last two decades due to its global spread as a multi-drug resistant (MDR) pathogen. Further, Carbapenem-Resistant Kp are emerging at an alarming rate. The objective of this study was (1) to evaluate the prevalence of β-lactamases, especially carbapenemases in Kp isolates from India, (2) determine the most prevalent sequence type (ST) & plasmids, and their association with β-lactamases. Clinical samples of K. pneumoniae (n=65) were collected from various pathology lab, drug susceptibility and minimum inhibitory concentrations (MIC) were detected. Whole genome sequencing (WGS) was done for (n=22) resistant isolates and WGS analysis was performed using various bioinformatics tools. Additional Indian MDR Kp genomes (n=187) were retrieved using Pathosystems Resource Integration Center (PATRIC) database. Detection of β-lactamase genes, location, plasmid replicons, and ST type of genomes were carried out using CARD, mlplasmids, PlasmidFinder, and PubMLST respectively. All data were analyzed and summarized using iTOL tool. ST231 was highest, followed by ST147, ST2096 & ST14 among Indian isolates. blaAmpH was detected as the most prevalent gene followed by blaCTX-M-15, blaTEM-1. Among carbapenemase genes, blaOXA-232 was prevalent and associated with ST231, ST2096 and ST14, which was followed by blaNDM-5 which was observed to prevalent in ST147, ST395 &ST437. ST231 genomes were most commonly found to carry Col440I and ColKP3 plasmids. ST16 carried mainly ColKP3, and Col (BS512) was abundantly present in ST147 genomes. One Kp isolate with novel MLST profile was identified, which carried blaCTX-M-15, blaOXA-1 and blaTEM-1. ST16 &ST14 from this study, which is mostly dual producer of carbapenem and ESBL genes, could be emerging high-risk clones in India.
ARTICLE | doi:10.20944/preprints202111.0288.v1
Online: 16 November 2021 (11:36:48 CET)
In dentistry, maxillofacial surgery, traumatology, and orthopedics, there is a need to use osteoplastic materials that have not only osteoinductive and osteoconductive properties but are also convenient for use. In the study, compositions based on collagen hydrogel were developed. Polylactide granules (PLA) or a traditional bone graft, a mixture of hydroxyapatite and β-tricalcium phosphate (HAP/β-TCP), were used for gel filling to improve mechanical osteoconductive properties of compositions. The mechanical tests showed that collagen hydrogels filled with 12 wt% highly porous PLA granules (elastic modulus 373 ± 55 kPa) or 35 wt% HAP/β-TCP granules (elastic modulus 451 ± 32 kPa) had optimal manipulative properties. All composite components were cytocompatible. The cell’s viability was above 90%, and the components’ structure facilitated the cell’s surface adhesion. The bone morphogenetic protein-2 (BMP-2) provided osteoinductive composition properties. It was impregnated directly into the collagen hydrogel with the addition of fibronectin or inside porous PLA granules. The implantation of a collagen hydrogel with BMP-2 and PLA granules into a critical-size calvarial defect in rats led to the formation of the most significant volume of bone tissue: 61 ± 15%. It was almost 2.5 times more than in the groups where a collagen-fibronectin hydrogel with a mixture of HAP/β-TCP (25 ± 7%) or a fibronectin-free composition with porous PLA granules impregnated with BMP-2 (23 ± 8%) were used. Subcutaneous implantation of the compositions also showed their high biocompatibility and osteogenic potential in the absence of a bone environment. Thus, the collagen-fibronectin hydrogel with BMP-2 and PLA granules has optimal biocompatibility, osteogenic, and manipulative properties.
ARTICLE | doi:10.20944/preprints202111.0220.v1
Subject: Materials Science, Other Keywords: β-Ga2O3 crystal; optical floating zone; saturable absorber; Q-switch
Online: 12 November 2021 (12:09:07 CET)
β-Ga2O3 crystal have attracted great attentions in the fields of photonics and photoelectronics because of its ultra wide-band gap and high thermal conductivity. Here, pure β-Ga2O3 crystal was successfully grown by optical floating zone (OFZ) method, and used as saturable absorbers to realize a passively Q-switched all-solid-state 1μm laser for the first time. By placing the as-grown β-Ga2O3 crystal into the resonator of Nd:GYAP solid-state laser, a Q-switched pulses at the center wavelength of 1080.4 nm are generated under a output coupling of 10%. The maximum output power is 191.5 mW while the shortest pulse width is 606.54 ns, and the maximum repetition frequency is 344.06 kHz. The maximum pulse energy and peak power are 0.567 μJ and 0.93 W, respectively. Our experimental results show that β-Ga2O3 crystal has great potential in the development of all-solid-state 1μm pulsed laser.
ARTICLE | doi:10.20944/preprints202110.0196.v1
Subject: Materials Science, Biomaterials Keywords: star polymer; β-cyclodextrin; tumor-targeted; disulﬁde bond; theranostic nanoparticles
Online: 13 October 2021 (11:00:40 CEST)
β-cyclodextrin-based star polymers have attracted much interest because of their unique structures and potential biomedical and biological applications. Herein, we synthesized well-defined folic acid (FA)-conjugated and disulfide bond-linked star polymer ((FA-Dex-SS)-βCD-(PCL)14) acted as theranostic nanoparticles for tumor-targeted magnetic resonance imaging (MRI) and chemotherapy. Theranostic nanoparticles were obtained by loading doxorubicin (DOX) and superparamagnetic iron oxide particles (SPIO) were loaded into the star polymer nanoparticles to obtain ((FA-Dex-SS)-βCD-(PCL)14@DOX/SPIO) theranostic nanoparticles. In vitro drug release studies showed that approximately 100% of the DOX was released from disulfide bond-linked theranostic nanoparticles within 24 h under a reducing environment in the presence of 10.0 mM GSH. DOX and SPIO could be delivered into HepG2 cells efficiently, owing to folate receptor-mediated endocytosis process of the nanoparticles and GSH triggered disulfide-bonds cleaving.Moreover, (FA-Dex-SS)-βCD-(PCL)14@DOX/SPIO showed strong MRI contrast enhancement properties. In conclusion, folate-decorated reduction-sensitive star polymeric nanoparticles are a potential theranostic nanoparticle candidate for tumor-targeted MRI and chemotherapy.
ARTICLE | doi:10.20944/preprints202109.0105.v1
Subject: Medicine & Pharmacology, Obstetrics & Gynaecology Keywords: endometrial cancer; tumor microenvironment; Wnt/β-catenin pathway; SATB1; SATB2
Online: 6 September 2021 (14:29:35 CEST)
Wnt/β-catenin signaling pathway plays an established role in various diseases and is considered a hallmark of endometrial cancer (EC). Special AT-rich sequence-binding protein 1 and 2 (SATB1 and SATB2) are nuclear matrix-associated proteins involved in chromatin remodeling and regulation of gene expression. SATB1 promotes the progression of numerous types of cancers, whereas SATB2 acts as a tumor suppressor. Despite a recent progress in our knowledge about EC, the exact mechanisms that control their proliferation and metastatic potential still remain unknown. The aim of our study was to investigate the association between Wnt3A, β-catenin, SATB1 and SATB2 protein level and the clinicopathological features of EC patients. 92 EC patients, aged 37-84, were enrolled to our study. The immunoexpression of WNT3A was found in specimens from all EC patients, β-catenin was expressed in 97% of the cases, SATB1 in 87%. The significant association between Wnt3a expression and tumor grade was found; moreover mean IRS for Wnt3a turned out to be significantly lower in high-grade tumors than in low-grade malignancies (p=0.038). In turn, immunoexpression of β-catenin varied significantly across FIGO stages and was associated with the presence of lymph node metastases. Mean IRS for β-catenin in patients with lymph node metastases was significantly lower than in those without (p = 0.028). The Kaplan-Meier analyses demonstrated a stepwise impairment of cancer overall survival with increasing SATB1 expression. In conclusion, both Wnt/β-catenin signaling pathway and SATB1 contribute to progression of EC. Downregulation of β-catenin may predispose to lymphatic spread of EC. In turn, downregulation of Wnt3a seems to be characteristic for high-grade tumors, but probably does not play a role in formation of lymph node metastases. The important role of SATB1 as a predictor of poor survival and could be helpful in establishing a more accurate prognosis in endometrial cancer patients.
Subject: Life Sciences, Biochemistry Keywords: copper; amyloid-β peptides; Alzheimer’s disease; oxidative stress; dopamine; neurodegeneration.
Online: 26 April 2021 (13:23:52 CEST)
The redox chemistry of copper(II) is strongly modulated by the coordination to amyloid-β peptides and by the stability of the resulting complexes. Amino terminal copper and nickel binding motifs (ATCUN) identified in truncated Aβ sequences starting with Phe4 show very high affinity for copper(II) ions. Herein, we study the oxidase activity of [Cu-Aβ4-x] and [Cu-Aβ1-x] complexes toward dopamine and other catechols. The results show that the CuII-ATCUN site is not redox-inert, the reduction of the metal is induced by coordination of catechol to the metal and occurs through an inner sphere reaction. The generation of a ternary [CuII-Aβ-catechol] species determines the efficiency of the oxidation, although the reaction rate is ruled by re-oxidation of the CuI complex. In addition to the N-terminal coordination site, the two vicinal histidines, His13 and His14, provide a second Cu-binding motif. Catechol oxidation studies together with structural insight from the mixed dinuclear complexes Ni/Cu-Aβ4-x reveal that the His-tandem is able to bind CuII ions independently of the ATCUN site, but the N-terminal metal complexation reduces the conformational mobility of the peptide chain, preventing the binding and oxidative reactivity toward catechol of CuII bound to the secondary site.
ARTICLE | doi:10.20944/preprints202012.0383.v1
Subject: Medicine & Pharmacology, Allergology Keywords: meprin α; meprin β; zinc metalloproteinase; medicinal chemistry; probe development
Online: 15 December 2020 (12:56:31 CET)
Meprin α is a zinc metalloproteinase (metzincin) that has been implicated in multiple diseases, including fibrosis and cancers. It has proven difficult to find small molecules that are capable of selectively inhibiting meprin α, or its close relative meprin β, over numerous other metzincins which, if inhibited, would elicit unwanted effects. We recently identified possible molecular starting points for meprin α-specific inhibition through an HTS effort (see part I, preceding paper). In part II we report the optimization of a potent and selective hydroxamic acid meprin α inhibitor probe which may help define the therapeutic potential for small molecule meprin α inhibition and spur further drug discovery efforts in the area of zinc metalloproteinase inhibition.
ARTICLE | doi:10.20944/preprints202010.0359.v1
Subject: Materials Science, Biomaterials Keywords: β-iPP; simultaneous biaxial stretching; sequential biaxial stretching; structure evolution
Online: 19 October 2020 (08:07:59 CEST)
In this paper, the lamellar structural evolution and microvoids variations of β-iPP during the processing of two different stretching methods, sequential biaxial stretching and simultaneous biaxial stretching, were investigated in detail. It was found that different stretching methods led to significantly different lamellae deformation modes, and the microporous membranes obtained from the simultaneous biaxial stretching exhibited better mechanical properties. For the sequential biaxial stretching, abundant coarse fibers originated from the tight accumulation of the lamellae parallel to the longitudinal stretching direction, whereas the lamellae perpendicular to the stretching direction were easily deformed and separated. Those coarse fibers were difficult to be separated to form micropores during the subsequent transverse stretching process, resulting in a poor micropores distribution. However, for the simultaneous biaxial stretching, the β crystal had the same deformation mode, that is, the lamellae distributed in different directions were all destroyed, forming abundant microvoids and little coarse fibers formation.
ARTICLE | doi:10.20944/preprints202009.0585.v1
Subject: Life Sciences, Biochemistry Keywords: Geobaccilus thermoleovorans IT-08; β-D-xylosidase; GbtXyl43A; kinetic characteristics
Online: 24 September 2020 (14:15:50 CEST)
GbtXyl43A, a β-xylosidase that is isolated from Geobacillus thermoleovorans IT-08 and grouped in GH43 family. The substitution of 121Asp residue with Asn in GbtXyl43A caused decrease the enzyme activity. The aim of this study, determine the kinetic characteristics of wild-type GbtXyl43A and D121N variant using Vmax, KM, kcat, and kcat/KM. These parameters indicated catalytic mechanism of GbtXyl43A and its derivative. All of them were produced in Escherichia coli BL21 star. The purification of wild-type GbtXyl43A using affinity chromatography, but D121N variant also required anion-exchange chromatography. The specific activity of wild-type GbtXyl43A and D121N variant were 0.471 U mg-1 in purity level 55,44 and 0.012 U mg-1 in purity level 2,407, respectively. Both enzymes had same molecular weight, ~58 kDa. The kinetic parameters of wild-type GbtXyl43A were KM: 2.845 mM, kcat: 0.033 s-1, Vmax: 0.0033 mM min-1and kcat/KM: 0.0115 s-1mM-1. Furthermore, the KM, kcat, Vmax, and kcat/KM values of D121N variant were 4.565 mM, 1.01 × 10-4 mM min-1, 0.140 × 10-4 s-1, and 0.0307 s-1mM-1, respectively. The KM value of the D121N variant was higher than its wild type and showed the affinity of D121N variant was lower than GbtXyl43A
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: COVID-19; SARS CoV-2; IFN-⍺; IFN-β; IFN-λ
Online: 2 August 2020 (11:31:40 CEST)
COVID-19 disease, caused by the SARS-CoV2 virus, is a potentially fatal disease that represents a serious public health and economic problem worldwide. The SARS-CoV2 virus infects the lower respiratory tract and can cause pneumonia in humans. ARDS is the leading cause of death in COVID-19 disease. One of the main characteristics of ARDS is the cytokine storm, an uncontrolled systemic inflammatory response resulting from the release of pro-inflammatory cytokines and chemokines and growth factors, by immune cells. The other important aspect of the disease is represented by the involvement of the vascular organ that undergoes endothelitis. Hyperinflammation and endothelitis contribute in various ways to trigger coagulation disorders with diffuse micro thrombotic and thromboembolic phenomena. Lastly, multiple organ failure may occur (MOF). Since so far there is no approved treatment, there is an urgent need to reposition known treatments, considered safe, to be included in trials. Naturally produced interferons represent the body's first line of defense against viruses. Pharmacological forms, obtained by means of genetic recombination techniques, have long been approved and used to treat numerous pathologies. Interferons are divided into three families, within which some subfamilies are distinguishable. Only IFN-II comprises a single isoform which has completely different aspects and functions. The IFN I and III, however, each comprise different subfamilies (17 subfamilies the IFN-I and 4 subfamilies the IFN-III), share many aspects, representing the body's first antiviral response, but play different roles. The use of IFNs has been studied in two severe hCoV (Human Coronavirus) diseases, closely related to COVID-19 disease, such as SARS and MERS. Numerous in vitro and in vivo studies have been conducted, often in combination with other antivirals. The results have been controversial. The positive results in vitro and in experimental animals were often not replicable in humans. The possible positioning of these molecules in the right window of therapeutic opportunity requires that the complex dialogue between IFN, inflammasome, cytokines, pro-inflammatory chemokines, growth factors and barrier function be shed light.
Subject: Chemistry, Medicinal Chemistry Keywords: 3,4-dimethoxy-β-nitrostyrene derivatives; antimicrobial agent; PTP1B; molecular docking
Online: 20 July 2020 (11:31:48 CEST)
A derivative series of 3,4-dimethoxy-β-nitrostyrene were synthesized and identified including new compound 6. The effect of antimicrobial activity of 3,4-alkyloxy modification of β-nitrostyrene was investigated. A molecular docking was also performed to obtain information about their interactions with Protein Tyrosine Phosphatase 1B (PTP1B). PTP1B containing cysteine 215 and arginine 221 as essential active residues plays a key role in signaling pathways that regulate various cell functions of microorganisms, which also act as negative regulator in signaling pathways of insulin that are involved in type 2 diabetes and other metabolic diseases. Compound 5 and 6 were the most potent as fragment of PTP1B inhibitor based on molecular docking, but compound 5 was more effective against Candida albicans. These compounds interact with serine 216 and arginine 221 residues. However, further research is needed to investigate their potential medicinal use.
ARTICLE | doi:10.20944/preprints201905.0290.v1
Subject: Life Sciences, Immunology Keywords: β-D-glucan; glucan binding protein; host defense; innate immunity
Online: 24 May 2019 (08:56:43 CEST)
The recognition of (1→3)-β-D-glucans (BGs) by β-1,3-D-glucan recognition protein (BGRP) found in invertebrates plays a significant role in the activation of toll pathway and pro-phenol oxidase system in insect host defense against fungal invasion. To examine the structural diversity of BGs in BGRP interaction, the binding specificity of BGRPs cloned from four different insectswas characterized using ELISA. Recombinant BGRPs expressed as Fc-fusion proteins of human IgG1 bound to solid phase BGs. Because of the binding specificities, the BGRPs were categorized into two different ultrastructure- binding characters. The BGRPs from Silkworm and Indian meal moth bound to BGs containing triple-helical structure. Other BGRPs from red flour beetle and yellow mealworm beetle showed no binding to triple-helical BGs, but to alkaline-treated BGs, which have partially opened helical conformation. These evidences suggest that the innate immune system distinguishes different BG conformations and it is equipped for the diversity of BG structures.
ARTICLE | doi:10.20944/preprints201903.0045.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Thienopyrimidines, RP-010, Prostate cancer, Metastasis, Wnt/β-catenin, Apoptosis.
Online: 4 March 2019 (13:37:02 CET)
Thienopyrimidines are a versatile group of compounds that contain a biologically active pharmacophore and reported to have anticancer efficacy in vitro. Here, we report for the first time, that thieno[3,2-d]pyrimidine - based compounds, designated the RP series, have efficacy in prostate cancer cells. The lead compound, RP-010, was efficacious in PC3 and DU-145 prostate cancer (PC) cells (IC50< 1µM). The cytotoxicity of RP-010 was significantly lower in normal cells. RP-010 (0.5, 1, 2, and 4 µM) arrested prostate cancer cells in the G2 phase of the cell cycle, induced mitotic catastrophe and apoptotic signaling in both PC cell lines. Mechanistic studies suggested that RP-010 (1 and 2 µM) inhibits the wingless-type MMTV (Wnt)/β-catenin signaling pathway, mainly by inducing β-catenin fragmentation, while down regulating important proteins in the pathway, i.e. LRP-6, DVL3, and c-Myc. Interestingly, RP-010 (1 and 2 µM) induced the nuclear translocation of the negative feedback proteins, Naked 1 and Naked 2, in the signaling pathway. In addition, RP-010 (0.5, 1, 2, and 4 µM) significantly decreased the migration and invasiveness of PC cells in vitro. Finally, RP-010 did not produce significant toxic effects in zebrafish at concentrations up to 6 µM. In conclusion, RP-10 is a promising anticancer compound in metastatic prostate cancer and did not produce overt toxicity in an in vivo zebrafish model. Future mechanistic and efficacy studies are needed in-vivo to optimize the lead compound RP-010 for clinical use.
ARTICLE | doi:10.20944/preprints201808.0432.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Breast cancer; Moracin D; Apoptosis; FOXM1; β-catenin; GSK 3β
Online: 24 August 2018 (10:58:08 CEST)
Though Moracin D derived from Morus alba was known to have anti-inflammatory and antioxidant activities, the underlying antitumor mechanism of Moracin D was never unveiled so far. Thus, in the recent study, the apoptotic mechanism of Moracin D was elucidated in breast cancer cells. Herein, Moracin D exerted significant cytotoxicity in MDA-MB231 and MCF7 cells. Also, Moracin D increased sub G1 population, cleaved poly (ADP-ribose) polymerase (PARP) and attenuated the expression of pro-cysteine aspartyl-specific protease (procaspase 3), c-Myc, cyclin D1, B-cell lymphoma 2 (Bcl-2),and X-linked inhibitor of apoptosis protein (XIAP) in MDA-MB231 cells. Of note, Moracin D reduced expression of Forkhead box M1 (FOXM1), β-catenin, Wnt3a, and upregulated glycogen synthase kinase 3 beta (GSK 3β) on Tyr216 along with disturbed binding of FOXM1 with β-catenin in MDA-MB-231 cells. Conversely, GSK3β inhibitor SB216763 reversed the apoptotic ability of Moracin D to reduce expression of FOXM1, β-catenin, pro-caspase3 and pro-PARP in MDA-MB-231 cells. Overall, these findings provide novel insight that Moracin D inhibits proliferation and induces apoptosis via suppression of Wnt3a/FOXM1/β-catenin signaling and activation of caspase and GSK3β
ARTICLE | doi:10.20944/preprints201612.0120.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: β-glucans; entero-endocrine system; intestinal hormones; microbiota; nutritional intervention
Online: 23 December 2016 (13:37:44 CET)
Recent interest in intestinal hormones has risen with the idea that they modulate glucose tolerance and food intake through a variety of mechanisms, and such hormones like peptide YY (PYY), ghrelin, glucagon-like peptide (GLP)-1 and 2, and cholecystokinin (CKK) are therefore excellent therapeutic candidates for the treatment of diabetes and obesity. Furthermore, in the recent years, multiple studies suggest that the microbiota is critically important for normal host functions, while impaired host microbiota interactions contribute to the pathogenesis of numerous common metabolic disorders. In this study, we considered the nutraceutical effects of β-glucans added to pasta at the concentration of 6g\100g. Ten participants have been recruited and hematochemical analyses and intestinal hormones tests have been performed before and after 30 days of pasta intake. Stool specimens have been studied for Lactobacillus Fermentum, Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium longum, and Enterococcus faecium presence before and after 30 days of nutritional intervention. After 30 days of regular intake of pasta enriched by β-glucans results have been evaluated. In conclusion, pasta prepared from barley flour enriched with β-glucans at 6% exhibit promising responses on glucose metabolism, on intestinal hormones responses and on microbiota modification.
ARTICLE | doi:10.20944/preprints202212.0434.v1
Subject: Chemistry, Analytical Chemistry Keywords: Adsorption; β-agonists; Magnetic-composite; Metal-Organic Frameworks; Pollutant; Removal; Terbutaline
Online: 23 December 2022 (01:51:10 CET)
Mechanochemical production of copper (II) isonicotinate Metal-Organic Framework ([Cu (INA)2]-MOF) and its modified magnetic iron composite ([Cu (INA)2]-MOF@Fe3O4]) allowed for the adsorptive removal of Terbutaline from water. A variety of characterization techniques, including Fourier, transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM), were used to elucidate the distinct chemical and morphological features of the two advanced materials. The optimal adsorption conditions were determined by investigating a wide range of adsorption-related variables, including contact time, initial Terbutaline concentration, adsorbent dosages pH, and temperature. The chemistry involved in the adsorption process between the adsorbents and the adsorbate molecules was evaluated using the best-fitting models, such as kinetics, isotherms, and thermodynamics, and the regeneration study was performed to evaluate the adsorbents' reusability. Incredibly maximum adsorption capacities (Qmax) of 1667 and 2500 mg L-1 were attained within 40 minutes under alkaline pH 11 by the [Cu (INA)2]-MOF and the [Cu (INA)2]-MOF@Fe3O4, respectively. The adsorbents have been proven to be good for the adsorption of Terbutaline as a priority pollutant in an aqueous solution, with pseudo-first order and Langmuir as the best-fitting models for the kinetic and isotherm models respectively.
ARTICLE | doi:10.20944/preprints202206.0328.v1
Subject: Biology, Ecology Keywords: mangrove forests; Marine Protected Areas; α-diversity; β-diversity; multivariate analyses
Online: 24 June 2022 (03:28:50 CEST)
Differences in fish assemblages’ structure and their relation with environmental variables (due to the variations in sampled seasons, habitats, and zones), were analyzed in two adjacent estuaries on the north Pacific coast of Mexico. Environmental variables and fish catches were registered monthly between August 2018 and October 2020. Multivariate analyses were conducted to define habitats and zones based on their environmental characteristics, and the effect of this variability on fish assemblages’ composition, biomass, and diversity (α and β) was evaluated. A total of 12,008 fish individuals of 143 species were collected using different fishing nets. Multivariate analyses indicated that fish assemblages’ structure was different between zones due to the presence, height, and coverage of distinct mangrove species. Additionally, factors such as depth and salinity showed effects on fish assemblages’ diversity (α and β-nestedness), which presented higher values in the ocean and remained similar in the rest of the analyzed zones and habitats. These results and the differences in species replacement (β-turnover) indicate the singularity of fish assemblages at estuaries (even in areas very close to the ocean), and the necessity to establish local management strategies for these ecosystems.
ARTICLE | doi:10.20944/preprints202204.0085.v1
Subject: Chemistry, Food Chemistry Keywords: aflatoxin M1; milk; dairy; cholesterol; β-cyclodextrin; food safety; global warming
Online: 11 April 2022 (03:18:05 CEST)
Approximately one-third of mankind is chronically exposed to the carcinogenic aflatoxin M1 contained in milk and dairy products and there is no ready to use procedure for decontamination purposes applicable in milk technology. Since β-cyclodextrin is frequently used in food industry, its effect on aflatoxin M1 concentration was investigated during cholesterol removal. So, milk samples were spiked with aflatoxin M1 at the average level 0.89 µg/kg and cholesterol removal was carried out by 2.0% (w/w) β-cyclodextrin addition. As found, average cholesterol concentration decreased by 92.3% while aflatoxin M1 concentration decreased to 0.53 µg/kg, i. e. by 39.1% after the treatment. The procedure itself is easy, inexpensive, and ready to use in milk processing technology on current production lines without any investments, thus fully applicable with a high potential of full aflatoxin M1 milk decontamination efficiency and such way to strengthen considerably the food safety issues associated with milk and dairy products on global level.
REVIEW | doi:10.20944/preprints202001.0063.v1
Subject: Life Sciences, Cell & Developmental Biology Keywords: hPSCs; hyperglycemia; insulin-secreting cells; β-cell precursors; pancreatic islets; transplantation.
Online: 8 January 2020 (05:30:34 CET)
Diabetes mellitus (DM) is one of the most prevalent metabolic disorders. In order to replace the function of the destroyed pancreatic beta cells in diabetes, islet transplantation is the widely practiced treatment; however, it has several limitations. As an alternative approach, human pluripotent stem cells (hPSCs) can provide an unlimited source of pancreatic cells that have the ability to secrete insulin in response to high blood glucose level. However, determination of the appropriate pancreatic lineage candidate for the purpose of cell therapy for treatment of diabetes is still debated upon. While hPSC-derived beta cells are perceived as the ultimate candidate, the efficiency needs further improvement in order to obtain a sufficient number of glucose responsive β-cells for transplantation therapy. On the other hand, hPSC-derived pancreatic progenitors can be efficiently generated in vitro and can further mature into glucose responsive beta cells in vivo after transplantation. Herein, we discuss the advantages and predicted challenges associated with the use of each of the two pancreatic lineage products for diabetes cell therapy. Furthermore, we address co-generation of functionally relevant islet cell subpopulations and structural properties contributing to glucose responsiveness of beta cells, as well as the available encapsulation technology for these cells.
COMMUNICATION | doi:10.20944/preprints201909.0313.v1
Subject: Life Sciences, Other Keywords: substrate-binding protein; sbp; abc transport; α/β-domain; rhodothermus arinus
Online: 27 September 2019 (12:16:07 CEST)
Substrate binding proteins (SBP) bind to specific ligands in the periplasmic region and bind to membrane proteins to participate in transport or signal transduction. Typical SBPs consist of two α/β domains and recognize the substrate by hinge motion between two domains. Conversely, short length Rhodothermus marinus SBP (named as RmSBP) exists around the methyl-accepting chemotaxis protein. We previously determined the crystal structure of RmSBP consisting of a single α/β domain, but the substrate recognition mechanism is still unclear. To better understand the short length RmSBP, we performed comparative structure analysis, computational substrate docking, and X-ray crystallographic study. RmSBP shares a high level of similarity in α/β domain with other SBP proteins, but it has a distinct topology in the C-term region. The substrate binding model suggested that conformational change in the peripheral region of RmSBP was required to recognize the substrate. We determined the crystal structures of RmSBP at pH 5.5, 6.0, and 7.5. RmSBP showed structural flexibility of the β1-α2 loop, β5-β6 loop, and extended C-term domain based on the electron density map and temperature B-factor analysis. These results provide information that will further the understanding of the function of the short length SBP.
ARTICLE | doi:10.20944/preprints201812.0059.v1
Subject: Medicine & Pharmacology, Other Keywords: Bioavailability; Box-Behnken design; β-cyclodextrin; erectile dysfunction; taste masking; vardenafil.
Online: 4 December 2018 (16:39:51 CET)
Because of lower solubility and considerable metabolism, vardenafil (VRD) bioavailability is 15 %. To get over this obstacle, this study aimed to increase the solubility, hasten the onset of action, and mask the unpleasant taste of VRD utilizing β-cyclodextrin (β-CD) and formulation of the inclusion complex as oral disintegrating tablets (ODTs). The solubility of the obtained complexes in various ratios has been studied. A Box-Behnken design (BBD) was utilized to investigate the influence of excipients on the quality of ODTs. The solubility of VRD was improved at 1:2 drug: β-CD ratio. The formulated VRD-ODTs exhibited satisfying results regarding the hardness and disintegration time. In addition, in vivo taste masking and disintegration time showed improved results, after placing the tablets in the oral cavity of the healthy volunteers. The pharmacokinetic parameters for the optimized VRD–ODTs exhibited a significant improvement with P < 0.05 in the maximum plasma concentration and reduction in the time needed to reach this concentration when compared with the marketed tablets. Finally, the optimized VRD-ODTs exhibited increased oral absorption of VRD and subsequent decreasing the time of onset of clinical effect and masking the unpleasant taste, which is favored for patients with erectile dysfunction.
ARTICLE | doi:10.20944/preprints201609.0123.v1
Subject: Life Sciences, Biochemistry Keywords: carbonic anhydrase; acetylcholinesterase; β-Lactam; 2-Azetidinone; enzyme inhibition; enzyme purification
Online: 30 September 2016 (05:38:45 CEST)
β-Lactams are pharmacologically important compounds because of their various biological uses, including antibiotic and so on. β-Lactams were synthesized from benzylidene-inden derivatives and acetoxyacetyl chloride. The inhibitory effect of these compounds was also examined for human carbonic anhydrase I and II (hCA I, and II) and acetylcholinesterase (AChE). The results reveal that β-lactams are inhibitors of hCA I, II and AChE. The Ki values of β-lactams (2a-k) were 0.44-6.29 nM against hCA I, 0.93-8.34 nM against hCA II, and 0.25-1.13 nM against AChE. Our findings indicate that β-lactams (2a-k) inhibit both CA isoenzymes and AChE at low nanomolar concentrations.
REVIEW | doi:10.20944/preprints202011.0563.v2
Subject: Medicine & Pharmacology, Allergology Keywords: Chromosomal instability; FA pathway; Radial figures; TGF pathway; MYC; p53; Bone marrow failure; cancer; physical abnormalities; infertility.
Online: 22 December 2020 (10:58:20 CET)
Abstract: Fanconi anemia (FA), a chromosomal instability syndrome, is caused by inherited pathogenic variants in any of 22 FANC genes, that cooperate in the FA/BRCA pathway. This pathway regulates the repair of DNA interstrand crosslinks (ICLs) through homologous recombination. In FA proper repair of ICLs is impaired, and accumulation of toxic DNA double strand breaks occurs. In order to repair this type of DNA damage, FA cells activate alternative error-prone DNA repair pathways, that may lead to the formation of gross structural chromosome aberrations of which radial figures are the hallmark of FA and their segregation during cell division are the origin of subsequent aberrations like translocations, dicentrics and acentric fragments. The deficiency in DNA repair has pleiotropic consequences in the phenotype of patients with FA, including developmental alterations, bone marrow failure and an extreme risk to develop cancer. The mechanisms leading to the physical abnormalities during embryonic development have not been clearly elucidated, however FA has features of premature aging with chronic inflammation mediated by pro-inflammatory cytokines, that results in tissue attrition, selection of malignant clones and cancer onset. Moreover, the effect of the FA/BRCA pathway in germinal cells, evidenced by infertility in patients with FA attests of chromosomal instability and cell death also occurring in the germinal compartment.
ARTICLE | doi:10.20944/preprints201910.0358.v1
Subject: Life Sciences, Other Keywords: epithelial-to-mesenchymal transition; TGF-β1; cAMP; A-kinase anchoring protein; Ezrin; AKAP95; Yotiao; cigarette smoke; COPD
Online: 31 October 2019 (02:15:56 CET)
Epithelial-to-mesenchymal transition (EMT) plays a role in chronic obstructive pulmonary diseases (COPD). Cyclic adenosine monophosphate (cAMP) can inhibit transforming growth factor-β1 (TGF-β1) mediated EMT. Although compartmentalization via A-kinase anchoring proteins (AKAPs) is central to cAMP signaling, functional studies on their therapeutic value in the lung EMT process are lacking. Bronchial epithelial (BEAS-2B, primary HAE cells) were exposed to TGF-β1. Epithelial (E-cadherin, ZO-1) and mesenchymal markers collagen Ӏ (mRNA, protein) were analyzed. St-Ht31 disrupted AKAP-PKA interactions. TGF-β1 release was measured by ELISA. TGF-β1-sensitive AKAPs Ezrin, AKAP95 and Yotiao were silenced using siRNA. Cell migration was analyzed by wound healing assay, xCELLigence, Incucyte. Prior to TGF-β1, dibutyryl-cAMP (dbcAMP), fenoterol, rolipram, cilostamide, forskolin were used to elevate intracellular cAMP. TGF-β1 induced morphological changes, decreased E-cadherin but increased collagen Ӏ and cell migration, a process reversed by PF-670462. TGF-β1 altered (mRNA, protein) expression of Ezrin, AKAP95 and Yotiao. St-Ht31 decreased E-cadherin (mRNA, protein), but counteracted TGF-β1-induced collagen Ӏ upregulation. Cigarette smoke (CS) increased TGF-β1 release, activated TGF signaling, augmented cell migration and reduced E-cadherin expression, a process blocked by TGF-β1 neutralizing antibody. Silencing of Ezrin, AKAP95 and Yotiao diminished TGF-β1-induced collagen Ӏ expression, as well as TGF-β1-induced cell migration. Fenoterol, rolipram, and cilostamide, in AKAP silenced cells pointed to distinct cAMP compartments. We conclude that Ezrin, AKAP95 and Yotiao promote TGF-β1-mediated EMT, linked to a TGF-β1 release by CS. AKAP members define the ability of fenoterol, rolipram and cilostamide to modulate the EMT process, and are potential relevant targets in the treatment of COPD.
ARTICLE | doi:10.20944/preprints202106.0532.v1
Subject: Life Sciences, Biochemistry Keywords: Cannabis Sativa L.; Aeroponics; Roots; Campesterol; Stigmasterol; β-Sitosterol; Epi-friedelanol; Friedelin
Online: 22 June 2021 (08:27:11 CEST)
Cannabis Sativa L. has been used for a long time to obtain food, fiber and as a medicinal and psychoactive plant. Today the nutraceutical potential of C. Sativa is being increasingly reappraised; however, C. Sativa roots remain poorly studied, despite citations in the scientific literature. In this direction, we identified and quantified the presence of valuable bioactives (namely β-sitosterol, stigmasterol, campesterol, friedelin and epi-friedelanol) in the root extracts of C. Sativa, a finding which might pave the way to the exploitation of the therapeutic potential of C. Sativa in all its parts. To facilitate roots harvesting and processing, aeroponic (AP) and aeroponic elicited cultures (AEP), have been set up and compared to soil-cultivated plant (SP): interestingly a considerable overgrowth of the plants - particularly of roots - and a significant increase (up to 20 fold in the case of β-sitosterol) in the total content of the above roots’ bioactive molecules have been observed in AP and AEP. In conclusion aeroponics, an easy, standardised, free of contaminant cultivation tecchnique, allows an ease harvesting/processing of roots along with a greater production of their secondary bioactive metabolites which could be utilized in the formulation of health promoting and health care products.
ARTICLE | doi:10.20944/preprints202104.0513.v1
Subject: Materials Science, Biomaterials Keywords: Hot isostatic pressing; β-Type titanium alloy; biomaterial; phase transformation; powder metallurgy
Online: 19 April 2021 (17:16:20 CEST)
The influence of the hot isostatic pressing (HIP) post-processing step on structural and phase changes, porosity healing and mechanical strength in a powder metallurgy Ti35Nb2Sn alloy was studied. Powders were pressed at room temperature at 750 MPa, and then sintered at 1,350°C in a vacuum for 3 h. The standard HIP process at 1,200°C and 150 MPa for 3 h was performed to study its effect on a Ti35Nb2Sn powder metallurgy alloy. The influence of the HIP process and cold rate on density, microstructure, the quantity of interstitial elements, mechanical strength and Young's modulus was investigated. HIP post-processing for 2 h at 1,200°C and 150 MPa led to greater porosity reduction and a marked retention of the β phase at room temperature. The slow cooling rate during the HIP process affected phase stability, with a large amount of α”-phase precipitate, which decreased the titanium alloy’s yield strength.
REVIEW | doi:10.20944/preprints202103.0154.v1
Subject: Biology, Anatomy & Morphology Keywords: β-glucans; polysaccharides; flavonoids; anthocyanins; antioxidants; biological role of pigments; gene families
Online: 4 March 2021 (11:19:12 CET)
Cereal crops, such as oats and barley, possess a number of valuable properties that meet the requirements for functional diet components. This review summarized the available information about bioactive compounds of oat and barley grain. The results of studying the structure and physicochemical properties of the cell wall polysaccharides of barley and oat are presented. The main components of the flavonoids formation pathway are shown and data, concerning anthocyanins biosynthesis in various barley tissues, are discussed. Moreover, we analyzed the available information about structural and regulatory genes of anthocyanin biosynthesis in Hordeum vulgare L. genome, including β-glucan biosynthesis genes in Avena sativa L species. However, there is not enough knowledge about genes responsible for biosynthesis of β-glucans and corresponding enzymes and plant polyphenols. The review also covers contemporary studies about collections of oat and barley genetic resources held by VIR. This review intended to provide information on the processes of biosynthesis of biologically active compounds in cereals that will promote further researches devoted to transcription factors controlling expression of structural genes and their role in other physiological processes in higher plants. Found achievements will allow breeders to create new highly productive varieties with the desirable properties.
REVIEW | doi:10.20944/preprints202010.0195.v1
Subject: Life Sciences, Biochemistry Keywords: Autophagy; Amyloid precursor protein (APP); β‐amyloid (Aβ); mTOR; Alzheimer’s disease (AD).
Online: 9 October 2020 (11:07:53 CEST)
Autophagy refers to the degradation of cytoplasmic constituents by a lysosomal-mediated pathway, which plays a critical role in maintaining cellular homeostasis. Importantly, dysregulation of autophagy has been implicated in multiple neurodegenerative disorders. Previous studies reported that autophagy affects the processing of amyloid precursor protein (APP), thus stimulating β‐amyloid (Aβ) production in Alzheimer’s disease (AD) eventually. Although the mechanism of autophagy modulation on APP processing and its pathogenesis has not yet been fully elucidated at the molecular level, but modulation of autophagy has received considerable attention as a promising approach for the treatment of AD. In the early stage of AD, Aβ may prompt autophagy to facilitate its removal via mTOR‐independent as well as-dependent pathways. However, a recent study proposed that autophagy processes are not properly regulated as AD continues to progress, and consequently, the production of Aβ tends to accumulate rapidly. Meanwhile, a number of autophagy-related genes (Atg) as well as APP genes are also thought to influence the development of AD, which may serve as a bi‐directional link to autophagy and AD pathology. In this review, we summarized current observations related to autophagy regulation and APP processing, focusing on their dynamic modifications associated with the progression of AD. Recent findings together highlight the essential role of autophagy in the removal and clearance of APP and Aβ deposition in the pathological condition of AD.
ARTICLE | doi:10.20944/preprints202207.0182.v1
Subject: Life Sciences, Biophysics Keywords: ADAM; Adaptive response; ALK1; ALK5; Bystander effects; Hyper-radiosensitive response; Low-dose radiation; Low dose rate; MMP; TGF-β3
Online: 12 July 2022 (09:25:07 CEST)
Hyper-radiosensitivity (HRS) is the increased sensitivity to low doses of ionizing radiation observed in most cell lines. We previously demonstrated that HRS is permanently abolished in cells irradiated at a low dose rate (LDR), in a mechanism dependent on transforming growth factor β3 (TGF-β3). In this study, we aimed to elucidate the activation and receptor binding of TGF-β3 in this mechanism. T-47D cells were pre-treated with inhibitors of potential receptors and activators of TGF-β3, along with addition of small extracellular vesicles (sEVs) from LDR primed cells, before their radiosensitivity was assessed by the clonogenic assay. The protein content of sEVs from LDR primed cells was analyzed with mass spectrometry. Our results show that sEVs contain TGF-β3 regardless of priming status, but only sEVs from LDR primed cells remove HRS in reporter cells. Inhibition of the matrix metalloproteinase (MMP) family prevents removal of HRS, suggesting an MMP-dependent activation of TGF-β3 in the LDR primed cells. We demonstrate a functional interaction between TGF-β3 and activin receptor like kinase 1 (ALK1), by showing that TGF-β3 removes HRS through ALK1 binding, independent of ALK5 and TGF-βRII. These results are an important contribution to a more comprehensive understanding of the mechanism behind TGF-β3 mediated removal of HRS.
ARTICLE | doi:10.20944/preprints202203.0154.v1
Subject: Medicine & Pharmacology, Gastroenterology Keywords: Colorectal cancer; Cancer stem cell; Neural progenitor cell; Wnt/β-catenin; K-Ras
Online: 10 March 2022 (14:26:20 CET)
Cancer stem cells (CSCs) are a tumor cell subpopulation that drives tumor progression and metastasis, leading to poor overall survival of patients. In colorectal cancer (CRC), hyper-activation of Wnt/β-catenin signaling by mutation of both Adenomatous polyposis coli (APC) and K-Ras increases the size of the CSC population. We previously showed that the CPD0857 inactivates Wnt/β-catenin signaling by promoting ubiquitin-dependent proteasomal degradation of β-catenin and Ras proteins, thereby decreasing proliferation and increasing apoptosis of CRC lines. CPD0857 also decreased growth and invasiveness of CRC cells harboring mutant K-Ras resistant to EGFR mAb therapy. Here, we show that CPD0857 treatment decreases proliferation and increases neuronal differentiation of neural progenitor cells (NPCs). CDP0857 effectively reduced expression of CSC markers and suppressed self-renewal capacity. CPD0857 treatment also inhibited proliferation and expression of CSC markers in D-K-Ras MT cells carrying K-Ras, APC and PI3K mutations, indicating inhibition of PI3K/AKT signaling. Moreover, CPD0857-treated xenograft mice showed regression of tumor growth and decreased numbers of CSCs in tumors. We conclude that CPD0857 could serve as the basis of a drug development strategy targeting CSCs activated through Wnt/β-catenin-Ras MAPK-PI3K/AKT signaling in CRCs.
ARTICLE | doi:10.20944/preprints202102.0038.v1
Subject: Life Sciences, Biophysics Keywords: chymotrypsin; β-casein; nanoparticles; UV-Vis spectroscopy; dynamic light scattering; quartz crystal microbalance.
Online: 1 February 2021 (13:59:40 CET)
Chymotrypsin is an important proteolytic enzyme in human digestion system that cleaves milk proteins, through hydrolysis reaction, which makes it interesting subject to study activity of milk proteases. In this work, we compared detection of chymotrypsin by spectrophotometric, dynamic light scattering (DLS) and quartz crystal microbalance (QCM) methods and determined the limit of chymotrypsin detection (LOD), 0.15 ± 0.01 nM for spectrophotometric, 0.67 ± 0.05 nM for DLS and 1.40 ± 0.30 nM for QCM methods, respectively. We discuss peculiarities and give perspective for implementation of detection methods and note that while the optical detection methods are simple to implement, the QCM method is more robust for sample preparation. We give an overview on methods and instruments for detection of chymotrypsin and other milk proteases.
REVIEW | doi:10.20944/preprints202006.0277.v2
Subject: Life Sciences, Cell & Developmental Biology Keywords: Diabetes; transcription factor; β-cell mass; pluripotent stem cells; pancreatic progenitors; cell therapy
Online: 19 October 2020 (16:04:27 CEST)
Understanding the biology underlying the mechanisms and pathways regulating pancreatic β-cell development is necessary to understand the pathology of diabetes mellitus (DM), which is characterized by the progressive reduction in insulin producing β-cell mass. Pluripotent stem cells (PSCs) can potentially offer an unlimited supply of functional β-cells for cellular therapy and disease modeling of DM. Homeobox protein NKX6.1 is a transcription factor (TF) that plays a critical role in pancreatic β-cell function and proliferation. In human pancreatic islet, NKX6.1 expression is exclusive toβ-cells and is undetectable in other islet cells. Several reports showed that activation of NKX6.1 in PSC-derived pancreatic progenitors (MPCs), expressing PDX1 (PDX1+/NKX6.1+), warrants their future commitment to monohormonal β-cells. However, further differentiation of MPCs lacking NKX6.1 expression (PDX1+/NKX6.1-) results in an undesirable generation of non-functional polyhormonal β-cells. The importance of NKX6.1 as a crucial regulator in MPC specification into functional β-cells directs attentions to further investigating its mechanism and enhancing NKX6.1 expression as a mean to increase β-cell function and mass. Here, we shed light on the role of NKX6.1 during pancreatic β-cell development and in directing the MPCs to functional monohormonal lineage. Furthermore, we address the transcriptional mechanisms and targets of NKX6.1 as well as its association with diabetes.
ARTICLE | doi:10.20944/preprints202007.0618.v1
Subject: Life Sciences, Immunology Keywords: Innate immune memory; inflammatory response; β-glucan; flow cytometry; primary chicken monocytes; macrophages
Online: 25 July 2020 (18:00:05 CEST)
Beta-glucan-stimulated mammalian macrophages show an increased responsiveness to secondary stimulation in a nonspecific manner. This phenomenon is known as trained innate immunity. Our study aimed to explore training of primary chicken monocytes. We hypothesized that primary chicken monocytes, similar to their mammalian counterparts, can be trained with β-glucan resulting in increased responses of these cells to a secondary stimulus. Primary blood monocytes of white leghorn chickens were primary stimulated with β-glucan microparticulates (M-βG), LPS, recombinant chicken interleukin-4 (IL-4) or combinations of these components for 48 h. On day 6, the primary stimulated cells were secondary stimulated with LPS. Nitric oxide (NO) production levels were measured as an indicator of pro-inflammatory activity. In addition, the cells were analysed by flow cytometry to characterize the population of trained cells and to investigate the expression of surface markers associated with activation. After the secondary LPS stimulation, surface expression of CSF1R and the activation markers CD40 and MHC-II was higher on macrophages that were trained with a combination of M-βG and IL-4 compared to unstimulated cells. This increased expression was paralleled by enhanced NO production. In conclusion, this study showed that trained innate immunity can be induced in primary chicken monocytes with β-glucan, which is in line with previous experiments in mammalian species. Innate immune training may have potential to improve health and vaccination strategies within the poultry sector.
ARTICLE | doi:10.20944/preprints201907.0092.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: Type 2 diabetes; urea albumin excretion; food frequency questionnaire survey; β-cryptoxanthin; fruits
Online: 8 July 2019 (14:44:24 CEST)
Background: The dietary factors and nutrients contributing to the prevention of microalbuminuria in type 2 diabetic nephropathy is unclear, so we investigated dietary factors affecting urinary albumin excretion in patients with type 2 diabetes. Methods: 42 patients with type 2 diabetes were participated, the subjects were divided to a normal albuminuria group (urinary albumin / creatinine ratio of less than 30 mg / g Cr) and a microalbuminuria group of 30 mg / g to 299 mg / g Cr. We performed casual blood sampling and conducted a food frequency questionnaire survey. Results: There were no significant differences in age, BMI and other physiological and biochemical data, the average daily intake of energy and many of nutrients, while β-cryptoxanthin was significantly lower in the microalbuminuria group than in the normal group (506.4 ± 793.9 μg/day vs. 715.3 ± 500.3 μg/day, p <0.05). The intake of 17 food groups per day showed that the intakes of fruits were significantly lower in the microalbuminuria group than in the normal group (76.9 ± 134.1 g vs. 111.9 ± 84.5 g, p <0.05). Conclusion: These results suggest that fruits and foods rich in β-cryptoxanthin would make it possible to prevent diabetic nephropathy progression.
REVIEW | doi:10.20944/preprints201809.0448.v1
Subject: Medicine & Pharmacology, Other Keywords: Extended spectrum β-lactamases, AmpC Carbapenemases, Carbapenemases, Classification, Phenotypic Detection, Clinically significant bacteria
Online: 24 September 2018 (08:57:40 CEST)
This review aimed at defining and classifying extended spectrum β-lactamases, ESBLs and carbapenemases, summarizing the different phenotypic methods used to detect production of these enzymes in clinically significant gram negative bacteria and also describing the methods that discourse challenges mostly encountered during detection of these enzymes in microbiology laboratories with the purpose of formulating recommendations on best practice to screen for these enzymes. We conclude that the modified double disk synergy, MDDS is not only suitable for the confirmation of ESBL production after screening isolates with the cephalosporin/clavulanate combination disc diffusion or broth micro-dilution methods but also distinguishes ESBL production and over-expression of AmpC-derepressed mutants and as well serves as an indicator for AmpC screening. Furthermore, we suggest cefotaxime, ceftazidime and cefpodoxime (for testing using a single drug) as indicator antibiotics of choice for ESBL detection. The MDDS and cefoxitin/AmpC inhibitor combination disc method, using cloxacillin and phenylboronic acid can be used as screening tests for AmpC production and either the AmpC disc test, the disc approximation test or the modified three dimensional extract test as confirmatory tests for AmpC production. We also suggest that confirmation of carbapenemase production be done with the modified hodge test, using Klebsiella pneumoniae ATCC 700603 as the indicator organism or the modified carbapenem inactivation method. However, to differentiate between the different classes of carbapenemases, boronic acid and EDTA based methods (double-disk synergy tests and combined-disk tests) using imipenem, meropenem and ertapenem, in combination with 3-aminophenylboronic acid and ethylene diamine tetra acetic acid be used.
ARTICLE | doi:10.20944/preprints201801.0156.v1
Subject: Biology, Other Keywords: Dunaliella salina; new isolates; characterization; light intensity; β-carotene; carotenoids; correlations; lutein; classification
Online: 17 January 2018 (12:04:11 CET)
The halotolerant microalga Dunaliella salina has been widely studied for natural β-carotene production. This work shows biochemical characterization of three newly isolated Dunaliella salina strains DF15, DF17 and DF40 compared with D. salina CCAP 19/30 (confirmed to be D. tertiolecta) and D. salina UTEX 2538 (also known as D. bardawil). Although all three new strains have been genetically characterized as Dunaliella salina strains, their ability to accumulate carotenoids and their capacity for photoprotection against high light stress are different. DF15 and UTEX 2538 reveal great potential for producing large amount of β-carotene and maintained a high rate of photosynthesis under light of high intensity; however, DF17, DF40 and CCAP 19/30 showed increasing photoinhibition with increasing light intensity, and reduced contents of carotenoids, in particular b-carotene, suggesting that the capacity of photoprotection is dependent on the cellular content of carotenoids, in particular β-carotene. Strong positive correlations were found between the cellular content of each of all-trans β-carotene, 9-cis β-carotene, all-trans α-carotene and zeaxanthin but not lutein in the D. salina strains. Lutein was strongly correlated with respiration in photosynthetic cells and strongly related to photosynthesis, chlorophyll and respiration, suggesting an important and not hitherto identified role for lutein in co-ordinated control of the cellular functions of photosynthesis and respiration in response to changes in light conditions, which is broadly conserved in Dunaliella strains. Statistical analysis based on biochemical data revealed a different grouping strategy from the genetic classification of the strains. The significance of these data for strain selection for commercial carotenoid production is discussed.
ARTICLE | doi:10.20944/preprints201706.0060.v1
Subject: Materials Science, Biomaterials Keywords: β-amyloid 42; differential pulse voltammetry; Neuro-degenerative disorders; ferrocyanide/ferricyanide redox couple
Online: 13 June 2017 (18:14:57 CEST)
A simple in vitro biosensor for the detection of β-amyloid 42 in phosphate-buffer saline (PBS) and undiluted human serum was fabricated and tested based on our platform sensor technology. The bio-recognition mechanism of this biosensor was based on the effect of the interaction between antibody and antigen of β-amyloid 42 to the redox couple probe of K4Fe (CN) 6 and K3Fe (CN) 6. Differential pulse voltammetry (DPV) served as the transduction mechanism measuring the current output derived from the redox coupling reaction. The biosensor was a three-electrode electrochemical system, and the working and counter electrodes were 50 nm thin gold film deposited by sputtering technique. The reference electrode was a thick-film printed Ag/AgCl electrode. Laser ablation technique was used to define the size and structure of the biosensor. Cost-effective roll-to-roll manufacturing process was employed in the fabrication of the biosensor making it simple and relatively inexpensive. Self-assembled monolayers (SAM) of 3-Mercaptopropionic acid (MPA) was employed to covalently immobilize the thiol group on the gold working electrode. A carbodiimide conjugation approach using N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride (EDC) and N–hydroxysuccinimide (NHS) was undertaken for cross-linking antibody of β-amyloid 42 to the carboxylic groups on one end of the MPA. The antibody concentration of β-amyloid 42 used was 18.75µg/mL. The concentration range of β-amyloid 42 in this study was from 0.0675µg/mL to 0.5µg/mL for both PBS and undiluted human serum. DPV measurements showed excellent response in this antigen concentration range. Interference study of this biosensor was carried out in the presence of Tau protein antigen. Excellent specificity of this β-amyloid 42 biosensor was demonstrated without interference by other species such as T-tau protein.
ARTICLE | doi:10.20944/preprints202109.0320.v1
Subject: Biology, Physiology Keywords: music; blood-brain barrier; lymphatic system; amyloid-β protein; detrended fluctuation analysis; electroencephalographic patterns.
Online: 20 September 2021 (09:02:40 CEST)
The lymphatic system of the brain meninges and head plays a crucial role in the clearance of amyloid-β protein (Aβ), a peptide thought to be pathogenic in Alzheimer’s disease (AD), from the brain. The development of methods to modulate lymphatic clearance of Aβ from the brain coild be a revolutionary step in the therapy of AD. The opening of the blood-brain barrier (OBBB) by focused ultrasound is considered as a possible tool for stimulation of clearance of Aβ from the brain of humans and animals. Here, we propose an alternative method of non-invasive music-induced OBBB that is accompanied by the activation of clearance of fluorescent Aβ (Fαβ) from the mouse brain. Using confocal imaging, fluorescence microscopy and magnetic resonance tomography, we clearly demonstrate that OBBB by music stimulates the movement of Fαβ and Omniscan in the cerebrospinal fluid and lymphatic clearance of Fαβ from the brain. We propose the extended detrended fluctuation analysis (EDFA) as a promising method for the identification of OBBB markers in the electroencephalographic (EEG) patterns. These pilot results suggest that music-induced OBBB and the EDFA analysis of EEG can be a non-invasive, low cost, labelling free, clinical perspective and completely new approach for the treatment and monitoring of AD.
ARTICLE | doi:10.20944/preprints202105.0032.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Alzheimer’s disease; cellular prion protein; amyloid β and PrP interaction in Alzheimer’s; BACE1; Aβ
Online: 5 May 2021 (10:45:04 CEST)
Alzheimer’s disease (AD) is the most common cause of dementia worldwide. Pathological deposits of neurotoxin proteins within the brain, such as amyloid-Beta and hyperphosphorylated tau tangles, are prominent features in AD. The prion protein (PrP) is involved in neurodegeneration via its conversion from the normal cellular form PrPc, to the infection form PrP Sc. Some studies indicated that posttranslationally modified PrPc isoforms plays a fundamental role in AD pathological progression. Several studies have shown that interaction of Aβ oligomers with N-terminal residues of the PrPc protein region appears critical for neuronal toxicity. The PrPc-Aβ binding always occur in AD brains and is never detected in nondemented controls and the binding of Aβ aggregates to PrPc is restricted to the N-terminus of PrPc.
Subject: Keywords: paraoxonases; oxidative stress; Alzheimer’s disease; brain; Tg2576 mice; astrocytes; hippocampus; amyloid-β; microglia; neurons
Online: 18 December 2020 (11:53:45 CET)
Background: Brain oxidative lipid damage and inflammation are common in neurodegenerative diseases such as Alzheimer’s disease (AD). Paraoxonase-1 and 3 (PON1 and PON3) protein expression have been described in tissues with no PON1 and PON3 gene expression. In the present study, we aimed to examine differences in PON1 and PON3 protein expression in the brain of a mouse model of AD. Methods: We used peroxidase-based and fluorescence-based immunohistochemistry in 5 brain regions (olfactory bulb, forebrain, posterior midbrain, hindbrain and cerebellum) of transgenic (Tg2576) mice with the Swedish mutation (KM670/671NL) responsible for a familial form of AD and corresponding wild-type mice. Results: We found intense PON1 and PON3 positive staining in star-shaped cells surrounding Aβ plaques in all Tg2576 mouse brain regions studied. Although we could not co-localize PON1 and PON3 with astrocytes, brain star-shaped cells, we found some co-localization of PON3 with microglia. Conclusions: These results suggest that 1) PON1 and PON3 cross the blood-brain barrier in discoidal HDLs and are transferred to specific brain cell types, and 2) PON1 and PON3 play an important role in preventing oxidative stress and lipid peroxidation in particular cell types, likely astrocytes and microglia, in AD pathology, and potentially in other neurodegenerative diseases
REVIEW | doi:10.20944/preprints202007.0137.v2
Subject: Medicine & Pharmacology, Other Keywords: Lysosomal Storage Disorders; GM2 gangliosidoses; Tay-Sachs disease; Sandhoff disease; β-Hexosaminidases; Therapeutic alternatives
Online: 5 August 2020 (05:05:13 CEST)
GM2 gangliosidoses are a group of pathologies characterized by GM2 ganglioside accumulation into the lysosome due to mutations on the genes encoding for the β-hexosaminidases subunits or the GM2 activator protein. Three GM2 gangliosidoses have been described: Tay-Sachs disease, Sandhoff disease, and the AB variant. Central nervous system dysfunction is the main characteristic of GM2 gangliosidoses patients that include neurodevelopment alterations, neuroinflammation, and neuronal apoptosis. Currently, there is not approved therapy for GM2 gangliosidoses, but different therapeutic strategies have been studied including hematopoietic stem cell transplantation, enzyme replacement therapy, substrate reduction therapy, pharmacological chaperones, and gene therapy. The blood-brain barrier represents a challenge for the development of therapeutic agents for these disorders. In this sense, alternative routes of administration (e.g. intrathecal or intracerebroventricular) have been evaluated, as well as the design of fusion peptides that allow the protein transport from the brain capillaries to the central nervous system. In this review, we outline the current knowledge about clinical and physiopathological findings of GM2 gangliosidoses, as well as the ongoing proposals to overcome some limitations of the traditional alternatives by using novel strategies such as molecular Trojan horses or advanced tools of genome editing.
ARTICLE | doi:10.20944/preprints201810.0167.v1
Subject: Chemistry, Applied Chemistry Keywords: phytosterols; mesocarp; oilseed; maturity; pod-blast; α-tocopherol; oil bodies; campesterol; stigmasterol; β-sitosterol
Online: 9 October 2018 (04:02:35 CEST)
The seeds of cultivated peanut, Arachis hypogaea, are an agronomically important crop produced for human nutrition, oilseed and feed stock. Peanut seed is the single most expensive variable input cost and thus producers require seed with excellence performance in terms of germination efficiency. During the maturation process, triglycerides are stored in oil bodies as an energy resource during germination and seedling development. The stability of oil body membranes is essential for nutrient mobilization during germination. This study focused on evaluating the phytosterol composition in seed components including the kernel, embryo (heart), and seed coat or skin. Samples of different maturity classes were analyzed for macronutrient and phytosterol content. The three most abundant phytosterols, β-sitosterol, campesterol, and stigmasterol, comprised 82.29%, 86.39%, and 94.25% of seed hearts, kernels, and seed coats, respectively. Stigmasterol concentration was highest in the seed kernel providing an excellent source of this sterol known to have beneficial effects on human health. Peanut hearts contained the highest concentration of sterols by mass potentially providing protection and resources for the developing seedling. The amount of α-tocopherol increases in peanut hearts during the maturation process providing protection from temperature stress and stability required for seedling vigor. These results suggest that phytosterols may play a significant role in the performance of seeds and provides a possible explanation for the poor germination efficiency of immature seeds.
ARTICLE | doi:10.20944/preprints201801.0201.v1
Subject: Biology, Animal Sciences & Zoology Keywords: Indian ocean; livestock; Extended-Spectrum β-Lactamase producing Enterobacteriaceae; risk factors; CTX-M; enzymes
Online: 22 January 2018 (12:02:53 CET)
In South Western Indian ocean (IO), Extended-Spectrum β-Lactamase producing Enterobacteriaceae (ESBL) are a main public health issue. In livestock, ESBL burden was unknown. The aim of this study was estimating the prevalence of ESBL on commercial farms in Reunion, Mayotte and Madagascar and genes involved. Secondly, risk factors of ESBL occurrence in broiler, beef cattle and pig farms were explored. In 2016-2017, commercial farms were sampled using boot swabs and samples stored at 4°C before microbiological analysis for phenotypical ESBL and gene characterization. A semi-directive questionnaire was performed. Prevalences observed in all production types and territories were elevated, except for beef cattle in Reunion which differed significantly. The most common ESBL gene was the CTX-M-1 subtype. Generalized linear models explaining ESBL occurrence varied between livestock production sectors and allowed identifying main protective (e.g., water quality control and detergent use for cleaning) and risk factors (e.g., recent antibiotic use, other farmers visiting the exploitation, pet presence). This study is the first to explore tools for antibiotic resistance management in IO farms. It provides interesting hypothesis to explore about antibiotic use in IO and ESBL transmission between pig, beef cattle and humans in Madagascar.
ARTICLE | doi:10.20944/preprints202104.0456.v1
Subject: Life Sciences, Biochemistry Keywords: ethidium; tetraphenylphosphonium; multidrug resistance; outer membrane permeability; efflux inhibitor; phenylalanyl-arginyl-β-naphtylamide, Polymyxin B
Online: 18 April 2021 (10:14:56 CEST)
Bacterial resistance to antibiotics due to an increased efficiency of the efflux is a serious problem in clinics of infectious diseases. Knowledge of the factors affecting the activity of efflux pumps would help to find the solution. For this, fast and trustful methods for the efflux analysis are needed. Here we analyzed how the assay conditions affect the accumulation of efflux indicators ethidium (Et+) and tetraphenylphosphonium in Salmonella enterica ser. Typhimurium cells. An inhibitor phenyl-alanyl-arginyl-β-naphtylamide was applied to evaluate the input of RND family pumps into the total efflux. In parallel to spectrofluorimetric analysis, we used an electrochemical assessment of Et+ concentration. Results of our experiments indicated that Et+ fluorescence increases immediately after the penetration of this indicator into the cells. However, when cells bind a high amount of Et+, intensity of the fluorescence reaches the saturation level and stops reacting to the accumulated amount of this indicator. For this reason, electrochemical measurements provide more trustful information about the efficiency of efflux when cells accumulate high amounts of Et+. Measure-ments of Et+ interaction with the purified DNA demonstrated that affinity of this lipophilic cation to DNA depends on the medium composition. The capacity of DNA to bind Et+ considerably de-creases in presence of Mg2+, Polymyxin B or when DNA is incubated in high ionic strength media.
ARTICLE | doi:10.20944/preprints201901.0097.v1
Subject: Chemistry, General & Theoretical Chemistry Keywords: 2-Hydroxypropyl-β-cyclodextrin (HPβCD); Replica exchange molecular dynamics (REMD); Conformational change; Cavity self-closure
Online: 10 January 2019 (11:43:44 CET)
2-Hydroxypropyl-β-cyclodextrin (HPβCD) has unique properties to enhance the stability and the solubility of low water-soluble compounds by inclusion complexation. Understanding of the structural properties of HPβCD and its derivatives based on the number of 2-hydroxypropyl (HP) substituents at the a-D-glucopyranose subunits is rather important. In this work, replica exchange molecular dynamics simulations were performed to investigate the conformational changes of single- and double-sided HP-substitution called as 6-HPβCDs and 2,6-HPβCDs, respectively. The results show that glucose subunits in both 6-HPβCDs and 2,6-HPβCDs have lower chance to flip than in βCD. Also, HP groups are occasionally blocking the hydrophobic cavity of HPβCDs, thus hindering the drug inclusion. We found that HPβCDs with high number of HP-substitutions are more likely to be blocked, while HPβCDs with double-sided HP-substitution are even more probable to be blocked. Overall, 6-HPβCDs with three and four HP-substitutions are highlighted as the most suitable structures for guest encapsulation based on our conformational analyses such as structural distortion, radius of gyration, circularity and cavity self-closure of the HPβCDs.