ARTICLE | doi:10.20944/preprints202210.0242.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: pheromones; androstenone; mouse deer; metabolic pathway; reproduction; hormones
Online: 18 October 2022 (02:44:00 CEST)
Two putative boar pheromones (Androstenone and Androstenol) were discovered in endangered mouse deer during captive breeding program. This study further examined the molecular characteristics, pheromone synthesis pathway, and the functional role of these pheromones in reproduction of mouse deer. CYP17A1 and CYB5 genes were cloned and expressed in HEK-293, COS-7 cell lines and gonads of mouse deer to investigate CYP17A1 gene’s andien-β-synthase activity towards synthesis of sex pheromones in mouse deer. An enzyme immunoassay was also developed and standardized to measure the fecal androstenone during reproductive cycles of mouse deer. Results showed that mouse deer’s CYP17A1 gene possesses andien-β-synthase activity and could transform pregnenolone into 5,16-androstadien-3β-ol. The expression of CYP17A1 gene upregulated in the testis and ovary, compared to other tissues in mouse deer. Significantly elevated pheromones and estrogens were recorded prior to delivery and postpartum estrus / mating in mouse deer. Further, there were weak correlations between fecal pheromones and estrogens/ androgens in mouse deer during breeding season. The findings suggest that the boar pheromones might play a direct role in the reproductive activities of mouse deer which might be used for breeding of mouse deer elsewhere.
REVIEW | doi:10.20944/preprints202306.1746.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: HTLV-1; ATL; Tax; HBZ; immunodeficient mouse; humanized mouse
Online: 26 June 2023 (05:19:47 CEST)
Adult T-cell leukemia (ATL) is an aggressive hematologic disease caused by human T-cell leukemia virus type 1 (HTLV-1) infection. Various animal models of HTLV-1 infection/ATL have been established to elucidate the pathogenesis of ATL and develop appropriate treatments. For analyses employing murine models, transgenic and immunodeficient mice are used because of the low infectivity of HTLV-1 in mice. HTLV-1 Tax and HBZ transgenic mice spontaneously develop tumors, and roles for both Tax and HBZ in cell transformation and tumor growth have been established. Severely immunodeficient mice were able to engraft ATL cell lines and have been used in preclinical studies of candidate molecules for the treatment of ATL. HTLV-1-infected humanized mice with an established human immune system are a suitable model to characterize cells in the early stages of HTLV-1 infection. This review outlines the characteristics of mouse models of HTLV-1 infection/ATL and describes progress made in elucidating the pathogenesis of ATL and developing related therapies using these mice.
REVIEW | doi:10.20944/preprints201710.0150.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: refinement; mouse welfare; mouse husbandry; mouse aggression; male mice; social organisation; group housing; single housing; animal husbandry; animal welfare; animal management
Online: 24 October 2017 (03:29:02 CEST)
It is widely recommended to group house male laboratory mice because they are ‘social animals’, but male mice do not naturally share territories and aggression can be a serious welfare problem. Even without aggression, not all animals within a group will be in a state of positive welfare. Rather, many male mice may be negatively affected by the stress of repeated social defeat and subordination, raising concerns about welfare and also research validity. However, individual housing may not be an appropriate solution, given the welfare implications associated with no social contact. An essential question is whether it is in the best welfare interests of male mice to be group- or singly-housed. This review explores the likely impacts, positive and negative, of both housing conditions, presents results of a survey of current practice and awareness of mouse behaviour, and includes recommendations for good practice and future research. We conclude that whether group- or single-housing is better (or less worse) in any situation is highly context-dependent according to several factors including strain, age, social position, life experiences, and housing and husbandry protocols. It is important to recognise this and evaluate what is preferable from animal welfare and ethical perspectives in each case.
ARTICLE | doi:10.20944/preprints201808.0084.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: genistein; ∆F508-CF; mouse; survival
Online: 4 August 2018 (11:24:00 CEST)
Genistein is a naturally occurring isoflavone found in soy. Mice homozygous for the ∆F508 mutation are characterized with severe intestinal disease and require constant laxative treatment for survival. This pathology mimics the intestinal obstruction (meconium ileus) seen in some cystic fibrosis (CF) patients. We therefore tested whether dietary supplementation with genistein would reduce the dependence of the ∆F508 CF mouse model on laxatives for survival, thereby improving mortality rates. At weaning (21 days), we maintained homozygous ∆F508 mice on three diet regimens for a period of up to 65 days; normal diet, normal diet + Colyte or genistein diet. Survival rates for males were as follows: standard diet (38%), standard diet plus Colyte (83%) or genistein diet (60%). Survival rates for females were as follows: standard diet (47%), standard diet plus Colyte (71%), or genistein diet (87%). Average weight of male mice fed genistein diet increased by ~2.5 g more compared to those with Colyte treatment. Genistein diet did not change final body weight of females. Expression of SGLT-1 increased 2-fold with genistein diet in females (no change in males). Expression of GLUT2 and GLUT5 was comparable between all diet groups. Genistein diet reduced the number of goblet cells per micometer of crypt depth in female, yet was without effect in males. We conclude that supplementation of diet with genistein for ~45 days increases the survival rate of female ∆F508-CF mice precluding the requirement for laxatives, and only improves weight gain in males.
COMMUNICATION | doi:10.20944/preprints202311.0805.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: mouse CXCR3; monoclonal antibody; CBIS method
Online: 14 November 2023 (05:37:03 CET)
C-X-C motif chemokine receptor 3 (CXCR3, CD183) is a G-protein-coupled receptor for CXCL9, CXCL10, and CXCL11. CXCR3 signaling induces chemotaxis of immune cells to inflammation sites and promotes inflammation in inflammatory diseases. Various mouse models to mimic the pathogenesis of each disease have been developed to understand mechanisms and evaluate therapeutics for these diseases. Although CXCR3 is an attractive target to suppress inflammation, anti-CXCR3 therapeutic agents have not been approved. In this study, we established a novel anti-mouse CXCR3 (mCXCR3) monoclonal antibody, Cx3Mab-4 (rat IgG1, kappa), using the Cell-Based Immunization and Screening method. Flow cytometric analysis demonstrated that Cx3Mab-4 bound to mCXCR3-overexpressed Chinese hamster ovary-K1 (CHO/mCXCR3) cells, but did not react to parental CHO-K1 cells. The dissociation constant of Cx3Mab-4 was determined as 1.3 × 10-9 M, indicating that Cx3Mab-4 possesses a high affinity to mCXCR3-expressing cells. Cx3Mab-4 could be useful for targeting CXCR3-expressing cells in preclinical mouse models.
COMMUNICATION | doi:10.20944/preprints202311.0501.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: mouse CXCR4; monoclonal antibody; CBIS method
Online: 8 November 2023 (15:52:54 CET)
The CXC chemokine receptor 4 (CXCR4, CD184) is a member of the G protein-coupled receptor family that is expressed in most leukocytes. Overexpression of CXCR4 is associated with poor prognosis in not only hematopoietic malignancy but also solid tumors. Because CXCR4 is an attractive target for tumor therapy, reliable preclinical murine models using anti-CXCR4 monoclonal antibodies (mAbs) have been warranted. This study established a novel anti-mouse CXCR4 (mCXCR4) mAb using the Cell-Based Immunization and Screening (CBIS) method. Flow cytometric analysis showed that an anti-mCXCR4 mAb, Cx4Mab-1 (rat IgG2a, kappa), recognized mCXCR4-overexpressed Chinese hamster ovary-K1 (CHO/mCXCR4) cells and endogenously mCXCR4-expressing mouse myeloma P3X63Ag8U.1 (P3U1) cells. Furthermore, Cx4Mab-1 did not recognize mCXCR4-knockout P3U1 cells. The dissociation constants of Cx4Mab-1 for CHO/mCXCR4 and P3U1 were determined as 6.4 × 10−9 M and 2.3 × 10-9 M, respectively, indicating that Cx4Mab-1 possesses a high affinity to both endogenous and exogenous mCXCR4-expressing cells. These results indicate that Cx4Mab-1 could be a useful tool for preclinical mouse models.
REVIEW | doi:10.20944/preprints202306.1927.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: circadian rhythms; transcription; pausing; mammalian; mouse
Online: 27 June 2023 (14:32:42 CEST)
Cell autonomous circadian oscillation is present in central and various peripheral tissues. The intrinsic tissue clock and various extrinsic cues drive gene expression rhythms. Transcription regulation is thought to be the main driving force for gene rhythms. However, how transcription rhythms arise remains to be fully characterized, due to the fact that transcription is regulated at multiple steps. In particular, Pol II recruitment and pause release are two critical regulatory steps that determine the status of Pol II pausing. Recently, we showed that Pol II pausing exhibits genomewide changes during daily transcription in mouse liver. In this article, we review historical as well as recent findings on the regulation of transcription rhythms. We also discuss the possible mechanisms for daily changes in Pol II pausing and the critical involvement of Pol II pausing regulation in generating rhythmic transcription output.
REVIEW | doi:10.20944/preprints202306.0360.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: eye movements; visual system; mouse vision
Online: 6 June 2023 (02:44:55 CEST)
The mouse visual system recently became the most popular model to study the cellular and circuit mechanisms of sensory processing. However, the importance of eye movements in mice only started to be appreciated recently. Eye movements provide a basis for active sensing and deliver insights into various brain functions and dysfunctions. A plethora of knowledge on the central control of eye movements and their role in perception and behaviour arose from work on primates. However, an overview of the known eye movement types in mice and a comparison to primates is missing.Here, we review the eye movement types described to date in mice and compare them to those observed in primates. We discuss the central neuronal mechanisms for their generation and control. Furthermore, we review the mounting literature on eye movements in mice during head-fixed and freely moving behaviours. Finally, we highlight gaps in our understanding and suggest future directions for research.
ARTICLE | doi:10.20944/preprints202205.0153.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: conduction; heterogeneity; inhomogeneity; dispersion; mouse; heptanol
Online: 11 May 2022 (13:08:36 CEST)
Background: Previous studies have associated slowed ventricular conduction in the arrhythmogenesis mediated by the gap junction and sodium channel inhibitor heptanol in mouse hearts but did not study the propagation patterns that might contribute to the arrhythmic substrate. This study used a multi-electrode array mapping technique, to further investigate different conduction abnormalities in Langendorff-perfused mouse hearts exposed to 0.1 or 2 mM heptanol. Methods: Multi-electrode array recordings were made from the left ventricular epicardium in spontaneously beating hearts, during right ventricular regular 8 Hz pacing or S1S2 pacing. Results: In spontaneously beating hearts, heptanol at 0.1 and 2 mM significantly reduced the heart rate from 314±25 to 189±24 and 157±7 bpm, respectively (ANOVA, P<0.05 and P<0.001). During regular 8 Hz pacing, Mean LATs were increased by 0.1 and 2 mM heptanol from 7.1±2.2 ms to 19.9±5.0 ms (P<0.05) and 18.4±5.7 ms (P<0.05). The standard deviation of mean LATs was increased from 2.5±0.8 ms to 10.3±4.0 ms and 8.0±2.5 ms (P< 0.05), and the median of phase differences was significantly increased from 1.7±1.1 ms to 13.9±7.8 ms and 12.1±5.0 ms by 0.1 and 2 mM heptanol (P<0.05). P5 took a value of 0.2±0.1 ms and was not significantly altered by heptanol at 0.1 or 2 mM (1.1±0.9 ms and 0.9±0.5 ms, P>0.05). P50 was increased from 7.3±2.7 ms to 24.0±12.0 ms by 0.1 mM heptanol and then to 22.5±7.5 ms by 2 mM heptanol (P< 0.05). P95 was increased from 1.7±1.1 ms to 13.9±7.8 ms by 0.1 mM heptanol and to 12.1±5.0 ms by 2 mM heptanol (P<0.05). These changes led to increases in the absolute inhomogeneity in conduction (P5-95) from 7.1±2.6 ms to 31.4±11.3 ms, 2 mM: 21.6±7.2 ms, respectively (P<0.05). The inhomogeneity index (P5-95/P50) was significantly reduced from 3.7±1.2 to 3.1±0.8 by 0.1 mM and then to 3.3±0.9 by 2 mM heptanol (P<0.05). Conclusion: Increased activation latencies, reduced CVs and increased dispersion index of conduction were associated with both spontaneous and induced ventricular arrhythmias.
REVIEW | doi:10.20944/preprints202208.0444.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: prostate cancer; knockout mouse models; genetically-engineered mouse models; xenografts; patient derived xenografts; organoids; signaling pathways
Online: 26 August 2022 (04:16:25 CEST)
In 2022, prostate cancer (PCa) is estimated to be the most commonly diagnosed cancer in men in the United States – almost 270,000 American men are estimated to be diagnosed with PCa in 2022 . This review compares and contrasts in vivo models of PCa with regards to the altered genes, signaling pathways, and stages of tumor progression associated with each model. The main type of model included in this review are genetically engineered mouse models, which include conditional and constitutive knockout model. 2D cell lines, 3D organoids and spheroids, xenografts and allografts, and patient derived models are also included. The major applications, advantages and disadvantages, and ease of use and cost are unique to each type of model, but they all make it easier to translate the tumor progression that is seen in the mouse prostate to the human prostate. Although both human and mouse prostates are androgen-dependent, the fact that the native, genetically unaltered prostate in mice cannot give rise to carcinoma is an especially critical component of PCa models. Thanks to the similarities between the mouse and human genome, our knowledge of PCa has been expanded, and will continue to do so, through models of PCa.
REVIEW | doi:10.20944/preprints202101.0337.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Diffuse intrinsic pontine glioma; molecular biology; patient derived xenografts; genetically engineered mouse model; humanized mouse model
Online: 18 January 2021 (12:50:14 CET)
Diffuse intrinsic pontine gliomas (DIPGs) account for ~15% of pediatric brain tumors, which invariably present with poor survival regardless of treatment mode. Several seminal studies have revealed that 80% of DIPGs harbor H3K27M mutation coded by HIST1H3B, HIST1H3C and H3F3A genes. The H3K27M mutation has broad effects on gene expression and is considered a tumor driver. Determination of the effects of H3K27M on posttranslational histone modifications and gene regulations in DIPG is critical for identifying effective therapeutic targets. Advanced animal models play critical roles in translating these cutting-edge findings into clinical trial development. Here, we review current molecular research progress associated with DIPG. We also summarize DIPG animal models, highlighting novel genomic engineered mouse models (GEMMs) and innovative humanized DIPG mouse models. These models will pave the way towards personalized precision medicine for the treatment of DIPGs.
ARTICLE | doi:10.20944/preprints202311.1282.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: mouse; mastitis; model; maggot antimicrobial peptide; treatment
Online: 21 November 2023 (07:38:26 CET)
Staphylococcus aureus(S. aureus) is associated with mastitis in dairy cows, this study investigates the therapeutic effect of maggot antimicrobial peptides on S. aureus induced mastitis in mice. The maggot AMP was isolated and purified, tested for antimicrobial activity, and used to treat a pathological model of rat mastitis. The concentration of 1.5mg/（Kg. BW）AMP was selected as intramammary treatment in S. aureus-induced mastitis in mice. The mice were divided into four groups of 30 mice each: group I (healthy control), group II (disease control), group III (AMP), and group IV (ciprofloxacin). To evaluate the therapeutic efficacy of maggot AMP in mastitis induced by S. aureus based on clinical presentation, mammary gland structure, bacterial load, histopathology, and cure. During the 7-day treatment period, all the mice in Group II died in the afternoon of the fifth day, and the clinical signs of the mice in Group III began to improve on the third day, as evidenced by the gradual recovery of the mice's mental status, dietary intake, and water intake. During the treatment period, the bacterial load count of Group III was significantly lower than that of Group II but higher than that of Group IV, while the bacterial load count of Group III gradually decreased and approached that of Group IV from the fifth to the seventh day. The levels of TNF-α in groups III and IV were significantly lower than those in group II, suggesting that maggot AMP has a certain inhibitory effect on TNF-α. Treatment with AMP@ 1.5 mg/(Kg. BW) showed restoration of clinical signs, reduced bacterial load, and lower TNF-α levels in mice, leading to significant improvement in histopathological changes as compared to disease controls. The final cure rate was 40% for mice in Group III compared to 70% for mice in Group IV, compared to all mice in Group II that died. From this study, it can be concluded that maggot AMP can be used as a potential alternative treatment option to antibiotics for the treatment of bovine mastitis.
ARTICLE | doi:10.20944/preprints202304.0565.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: Chrysomycin A; Xenograft mouse model; Glioblastoma; Apoptosis
Online: 19 April 2023 (08:00:29 CEST)
Glioblastoma (GBM) is a major type of primary brain tumors without ideal prognosis and it’s necessary to find novel compound possessing therapeutic effect. Chrysomycin A (Chr-A) has been reported to inhibit the proliferation, migration and invasion of U251 and U87-MG cells, but the mechanism of Chr-A against glioblastoma in vivo and whether Chr-A modulates apoptosis of neuroglioma cells is unclear.The present study was to elucidate the potential of Chr-A against glioblastoma in vivo and how Chr-A modulates apoptosis of neuroglioma cells. Briefly, The an-ti-glioblastoma activity was assessed in human glioma U87 xenografts nude mice. Chr-A-related targets were identified by RNA-seq. Apoptotic ratio and caspase 3/7 activity of U251 and U87-MG cells were assayed by flow cytometry. Apoptosis-related proteins and possible molecular mecha-nism were validated via Western blotting. The results showed that Chr-A treatment significantly inhibits glioblastoma progression in xenografts nude mice, and enrichment analysis suggested that apoptosis, PI3K-Akt and Wnt signaling pathway were involved in the possible mechanism. Chr-A increased apoptotic ratio and the activity of caspase 3/7 in U251 and U87-MG cells. Western blot revealed that Chr-A broke the balance between Bax and Bcl-2 activating caspase cascade re-action and downregulated the expression of p-Akt and p-GSK-3β, suggesting that Chr-A may contribute to glioblastoma regression modulating Akt/GSK-3β signaling pathway to promote apoptosis of neuroglioma cells in vivo and in vitro. Therefore, Chr-A may hold therapeutic promise for glioblastoma.
COMMUNICATION | doi:10.20944/preprints202303.0309.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mouse CCR6; monoclonal antibody; epitope; ELISA; SPR
Online: 16 March 2023 (14:13:28 CET)
CC chemokine receptor 6 (CCR6) is one of the members of G protein-coupled receptor (GPCR) family that is upregulated in many immune-related cells, including B lymphocytes, effector and memory T cells, regulatory T cells, and immature dendritic cells. Coordination between CCR6 and its ligand CC motif chemokine ligand 20 (CCL20) is deeply involved in the pathogenesis of various diseases, such as cancer, autoimmune diseases, and psoriasis. Therefore, CCR6 is an attractive target for therapy and is being investigated as a diagnostic marker for patients. In a previous study, we developed an anti-mouse CCR6 (mCCR6) monoclonal antibody (mAb), C6Mab-13 (rat IgG1, kappa), applicable for flow cytometry by immunizing a rat with N-terminal peptide of mCCR6. This study investigated the binding epitope of C6Mab-13 using enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR) methods with the synthesized point mutated-peptides within 1-20 amino acids region of mCCR6. In ELISA, C6Mab-13 lost the reaction to the alanine-substituted peptide of D11A. The epitope of C6Mab-13 was identified to be Asp11 in ELISA. Furthermore, in SPR analysis, the dissociation constants (KD) could not be calculated for G9A and D11A mutants due to lack of binding. The SPR analysis demonstrated that the C6Mab-13 epitope comprises Gly9 and Asp11. Taken together, the key binding epitope of C6Mab-13 was determined to be around Asp11 on mCCR6. Based on the epitope information, C6Mab-13 could be useful for further functional analysis of mCCR6 in future studies.
ARTICLE | doi:10.20944/preprints202103.0411.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: HDV; mouse model; AAV; HDAg; Liver damage
Online: 16 March 2021 (10:14:06 CET)
Hepatitis delta virus (HDV) infection causes the most severe form of viral hepatitis but little is known about the molecular mechanisms involved. The recently developed HDV mouse model based on the delivery of HDV replication-competent genomes using adeno-associated vectors (AAV) develop a liver pathology very similar to the human disease, and allowed us to perform mechanistic studies. We have generated different AAV-HDV mutants to eliminate the expression HDV antigens (HDAgs), characterized them both in vitro and in vivo. We confirmed that S-HDAg is essential for HDV replication and cannot be replaced by L-HDAg or host cellular proteins, and the L-HDAg is essential for HDV infectious particle production. We have also found that the lack of L-HDAg resulted in the increase of of S-HDAg expression levels and the exacerbation of liver damage which is T cell independent but is associated with an increment in liver inflammation. Interestingly, early expression of L-HDAg significantly ameliorated the liver damage induced by the mutant expressing only the S-HDAg. In summary, the use of AAV-HDV represents a very attractive platform to interrogate in vivo the role of viral components in the HDV life cycle and to better understand the mechanism of HDV-induced liver pathology.
REVIEW | doi:10.20944/preprints202103.0093.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: glioma; GEMM; isocitrate dehydrogenase; PDX; mouse model
Online: 2 March 2021 (12:54:59 CET)
Despite advances in understanding of the molecular pathogenesis of glioma, outcomes remain dismal. Developing successful treatments for glioma requires faithful in vivo disease modeling and rigorous preclinical testing. Murine models, including xenograft, syngeneic, and genetically engineered models, are used to study gliomagenesis, identify methods of tumor progression, and test novel treatment strategies. Since the discovery of highly recurrent isocitrate dehydrogenase (IDH) mutations in lower-grade gliomas, there is increasing emphasis on effective modeling of IDH mutant brain tumors. Improvements in preclinical models that capture the phenotypic and molecular heterogeneity of gliomas are critical for the development of effective new therapies. Herein, we explore the current status, advancements, and challenges with contemporary murine glioma models.
REVIEW | doi:10.20944/preprints202012.0171.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Mouse Grimace Scale; Pain; Validity; Methods; Reliability
Online: 7 December 2020 (15:13:05 CET)
The Mouse Grimace Scale (MGS) was developed 10 years ago to assess pain through characterisation of changes in five facial features or action units. The strength of the technique is that it is proposed to be a measure of spontaneous or non-evoked pain. A comprehensive scoping review of the academic literature was performed. The MGS has been employed mainly in evaluation of acute pain, particularly in the pain and neuroscience research fields. There has however been use of the technique in a wide range of fields, and based on limited study it does appear to have utility for pain assessment across a spectrum of animal models. Use of the method does allow detection of pain of a longer duration, up to a month post-initial insult. There has been less use of the technique using real-time methods and this is an area in need of further research.
ARTICLE | doi:10.20944/preprints201910.0335.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: lipopolysaccharides; mucin; ileum; MUC2; mucosal barrier; mouse
Online: 29 October 2019 (10:50:10 CET)
The small intestinal villus is covered with a thick layer of mucus that is secreted by goblet cells and functions primarily to first barrier from damage by toxic substance. Recent studies showed that goblet cells and mucins involved in complex immune function. Lipopolysaccharide (LPS) is widespread in the housing of livestock, which can induce bacterial infection symptoms and immunological stress within a short of time. Therefore, we aimed to study the effects of long-term exposure to different doses of LPS on intestinal mucus layer and immune barrier. The result showed that mucus layer thickness and goblet cell functions were significantly increased after low doses of LPS. The intestinal mucosal barrier can block the bacteria of the lumen, but LPS can penetrate this barrier into the blood, putting the body in a state of chronic low-grade inflammation and reducing the body’s immune function. However, after long-term exposure to high doses of LPS, a large number of lysosomes in goblet cells caused loss of function, and mucus layer thickness was significantly decreased. A large amount of LPS stuck to the mucus, leading to normal LPS and inflammatory cytokines level of plasma. The intestinal tissue morphology was damaged, and a number of immune cells were necrosis in the intestine. Collectively, long-term exposure to low doses of LPS lead to chronic low-grade inflammation in the body. Long-term exposure to high doses of LPS can be directly linked to the severity of the immunosuppression in the body.
ARTICLE | doi:10.20944/preprints201807.0043.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: nimbolide; LC-MS/MS; mouse; serum; pharmacokinetics
Online: 3 July 2018 (12:15:37 CEST)
A sensitive and robust liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the determination of nimbolide in mouse serum. Exemestane was used as the internal standard (IS). Here, we employed acetonitrile-based protein precipitation (PPT) for serum sample preparation, and performed chromatographic separation using an ODS Hypersil C18 column (100×2.1 mm, 5µm) with gradient elution (0.1% formic acid in water vs 100% acetonitrile). The run time was 6 min. Instrumental analysis was performed by electrospray ionization tandem mass spectrometry (ESI-MS/MS) in the multiple-reaction monitoring (MRM) under positive mode. A good linear calibration was achieved in the 5–1000 ng/ml range. The intra- and inter-day precisions for nimbolide were ≤ 12.6% and ≤ 13.9 % respectively. Intra-day accuracy ranged from 96.9% – 109.3% while inter-day accuracy ranged from 94.3% – 110.2%. The matrix effect of nimbolide, detected but consistent at low and high concentrations, do not affect linearity of standard curve. In conclusion, we have developed and validated a sensitive analytical method for determination of a novel natural compound nimbolide in mouse serum and it has been successfully applied to our preclinical study in investigating the pharmacokinetic properties of nimbolide, which could greatly facilitate the preclinical development of the promising lead compound for anticancer therapy.
ARTICLE | doi:10.20944/preprints202212.0069.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: human adipose mesenchymal stem cell; human peripheral blood mononuclear cells; cytokine; immune cell frequency; C57BL/6 mouse; ICR mouse
Online: 5 December 2022 (09:01:51 CET)
Human adipose stem cell-derived extracellular vesicles (hASC-EVs) are key mediators of paracrine signaling with promising therapeutic applications. Although hASC-EVs are derived from human cells and are less immunogenic, their immunogenicity cannot be completely excluded. Here, we evaluate the immune responses of ICR and C57BL/6 mice to high doses of hASC-EVs for 10 days after injection. Lymphocyte subpopulations are analyzed using flow cytometry at 0.5, 1, 3 and 24 h post injection. In the spleen and blood of C57BL/6 mice, neutrophils sharply increased at 0.5 h and decreased at 3 h following hASC-EV treatment. We observe increased proportions of monocytes, macrophages, and natural killer cells at 3 h but returned to similar level of vehicle control at 24 h post injection in the spleen and blood of ICR mice. Although the in vivo experiments reveal different immune responses to hASC-EV treatment in C57BL/6 and ICR strains, no major changes occur in human peripheral blood mononuclear cell composition after applying hASC-EVs in vitro. In conclusion, unlike those in mice, immune responses to hASC-EVs in humans are not detectable, indicating a minimal risk of fatal side-effects from hASC-EV-based therapies.
REVIEW | doi:10.20944/preprints202307.1424.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: prostate cancer; mouse model; xenograft; PDX; CRISPR; probasin
Online: 21 July 2023 (07:36:00 CEST)
Prostate cancer is a common cancer among men and typically progresses slowly for several decades before becoming aggressive and spreading to other organs, leaving few treatment options. While large animals have been studied, the dog's prostate is anatomically similar to humans and has been used to study spontaneous prostate cancer. However, most research currently focuses on the mouse as a model organism due to the ability to genetically modify their prostatic tissues for molecular analysis. One hallmark in this research was the identification of the prostate-specific promoter Probasin, allowing for prostate-specific expression of transgenes. This has led to generations of mice with aggressive prostatic tumors through overexpression of the SV40 oncogene. The Probasin promoter is also used to drive Cre expression and allow researcher to generated prostate specific loss-of-function studies. Another landmark in the process of modeling prostate cancer in mice was orthoptic delivery of viral particles. This technology allows selective overexpression of oncogenes from lentivirus or the use of CRISPR to generate complex loss of function studies. These genetic modified models are complemented by classical xenografts of human prostate tumor cells in immune deficient mice. Overall, pre-clinical models have provided a portfolio of model systems to study and address complex mechanisms in prostate cancer for improved treatment options. This review will focus on the advances of each technique.
ARTICLE | doi:10.20944/preprints202307.0140.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: Phytocannabinoids; Fmr1; mouse behavior; neurodevelopmental disorders; interleukins; neurotrophins
Online: 4 July 2023 (09:38:15 CEST)
Phytocannabinoids, including the non-addictive cannabis component cannabidivarin (CBDV), have been reported to hold therapeutic potential in several neurodevelopmental disorders (NDDs). Nonetheless, the therapeutic value of phytocannabinoids for treating Fragile X syndrome (FXS), a major NDD, remains unexplored. Here, we characterized the neurobehavioral effects of CBDV at doses of 20 or 100 mg/kg in the Fmr1-knockout (Fmr1-KO) mouse model of FXS using two temporally-different intraperitoneal regimens: subchronic 10-day delivery during adulthood (Study 1: rescue treatment) or chronic 5-week delivery at adolescence (Study 2: preventive treat-ment). Behavioral tests assessing FXS-like abnormalities included anxiety, locomotor, cognitive, social and sensory alterations. Expression of inflammatory and plasticity markers was investigated in the hippocampus and prefrontal cortex. When administered during adulthood (Study 1), the effects of CBDV were marginal, rescuing at the lower dose only the acoustic hyper-responsiveness of Fmr1-KO mice and at both doses, their altered hippocampal expression of neurotrophins. When administered during adolescence (Study 2), CBDV at both doses prevented the cognitive, social and acoustic alterations of adult Fmr1-KO mice and modified the expression of several inflammatory brain markers in both wild-type littermates and mutants. These findings warrant the therapeutic potential of CBDV for preventing neurobehavioral alterations associated with FXS, highlighting the relevance of its early administration.
BRIEF REPORT | doi:10.20944/preprints202205.0324.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: aortic aneurysms; aortic dissection; fludrocortisone; angiotensin; hypercholesterolemia; mouse
Online: 24 May 2022 (06:05:35 CEST)
Background and Objective: In an experiment designed to explore the mechanisms of fludrocortisone-induced high blood pressure, we serendipitously observed aortic aneurysms in mice infused with fludrocortisone. The purpose of this study was to investigate whether fludrocortisone induces aortic pathologies in both normocholesterolemic and hypercholesterolemic mice. Methods and Results: Male adult C57BL/6J mice were infused with either vehicle (85% polyethylene glycol 400 (PEG-400) and 15% dimethyl sulfoxide (DMSO); N=5) or fludrocortisone (12 mg/kg/day dissolved in 85% PEG-400 and 15% DMSO; N=15) for 28 days. Fludrocortisone-infused mice had higher systolic blood pressure, compared to mice infused with vehicle. Fludrocortisone induced aortic pathologies in 4 of 15 mice with 3 having pathologies in the ascending and aortic arch regions and 1 having pathology in both the ascending and descending thoracic aorta. No pathologies were noted in abdominal aortas. Subsequently, we infused either vehicle (N=5/group) or fludrocortisone (N=15/group) into male ApoE -/- mice fed a normal laboratory diet or LDL receptor -/- mice fed either normal or Western diet. Fludrocortisone increased systolic blood pressure, irrespective of mouse strain or diet. In ApoE -/- mice infused with fludrocortisone, 2 of 15 mice had ascending aortic pathologies, but no mice had abdominal aortic pathologies. In LDL receptor -/- mice fed normal diet, 5 had ascending/arch pathologies, 1 had pathologies in the ascending, arch, and suprarenal aortic regions. In LDL receptor -/- mice fed Western diet, 2 died of aortic rupture in either the descending thoracic or abdominal region, and 2 of the 13 survived mice had ascending/arch aortic pathologies. Aortic pathologies included hemorrhage, wall thickening or thinning, or dilation. Given the low incidence, only ascending aortic diameter in LDLR -/- mice fed Western diet reached statistical significance, compared to their vehicle. Conclusion: Fludrocortisone induces aortic pathologies independent of hypercholesterolemia. The findings in mouse studies have the potential to provide caution to people who are taking or have taken fludrocortisone that could have an increased risk of aortic pathologies.
ARTICLE | doi:10.20944/preprints202107.0023.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: breast cancer; mouse-mammary tumor virus; epidemiology; etiology
Online: 1 July 2021 (11:31:48 CEST)
Breast cancer, although the most frequently diagnosed malignant tumour in humans, has a less clear aetiology compared to other frequent cancer types. Mouse-mammary tumour virus (MMTV) is involved in breast cancer in mice and dogs and might play a role in the aetiology of some breast cancers in humans, since it has been identified in 20-40% of breast cancer samples in Western Europe, USA, Australia and some other parts of the world population. The purpose of our study was to identify MMTV DNA sequences in breast tissue samples from breast cancer patients operated in our regional centre from Romania. We have selected 75 patients with non-metastatic breast cancer treated with curative intent and searched with PCR the MMTV-like DNA sequence in the breast cancer tissue and normal breast tissue obtained from the same patients. Since none of the examined samples was positive for MMTV-like target sequences on PCR we could not prove that MMTV plays a role in the aetiology of breast cancer in our patient group. This finding is similar to publications of other geographically related research groups and might be due to the fact that only the Mus musculus domesticus mouse species was proven to carry infectious MMTV, but not the Mus musculus musculus species, which is specific to South-Eastern Europe (including Romania) and some parts of Asia.
ARTICLE | doi:10.20944/preprints201911.0292.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: NHEJ; double-strand breaks; mouse model; lymphocyte; neurodevelopment
Online: 24 November 2019 (15:57:38 CET)
Classical non-homologous end joining (NHEJ) is a molecular pathway that detects, processes and ligates DNA double-strand breaks (DSBs) throughout the cell cycle. Mutations in several NHEJ genes result in neurological abnormalities and immunodeficiency both in humans and mice. The NHEJ pathway is required for the V(D)J recombination in developing B and T lymphocytes, and for class switch recombination in mature B cells. Ku heterodimer formed by Ku70 and Ku80 recognizes DSBs and facilitates the recruitment of accessory factors (e.g., DNA-PKcs, Artemis, Paxx and Mri/Cyren) and downstream core factors subunits XLF, XRCC4 and Lig4. Accessory factors might be dispensable for the process depending on the genetic background and DNA lesion type. To determine the physiological role of Mri in DNA repair and development, we introduced frame-shift mutation in the Mri gene in mice. We then analyzed the development of Mri-deficient mice as well as wild type and immunodeficient controls. Mice lacking Mri possessed reduced levels of class switch recombination in B lymphocytes and slow proliferation of neuronal progenitors when compared to wild type littermates. Human cell lines lacking Mri were as sensitive to DSBs as WT controls. Overall, we concluded that Mri/Cyren is largely dispensable for DNA repair and mouse development.
ARTICLE | doi:10.20944/preprints202201.0433.v1
Subject: Social Sciences, Behavior Sciences Keywords: cohousing; stress; CD1 mouse; C57BL/6J mouse; Sprague Dawley rat; fecal corticosterone or cortisol metabolites; dyadic social interaction; conditioned place preference
Online: 28 January 2022 (11:13:58 CET)
Rats, including those of the Sprague Dawley strain, may kill mice. Because of this muridical behavior, it is standard practice in many research animal housing facilities to separate mice from rats (i.e., the predators) to minimize stress for the mice. We therefore tested the effect of cohousing on the stress levels of mice from either the C57BL/6J (BL6) or the CD1 strain and Sprague Dawley (SD rat) by determining their fecal corticosterone or cortisol metabolites (FCM) concentration and investigated how cohousing impacts a behavioral assay, i.e., conditioned place preference for intragenus (i.e., mouse-mouse or rat-rat) dyadic social interaction (DSI CPP) that had been shown be sensitive to social factors, especially to handling by humans. We found that the two delivery batches of BL6 mice or SD rats, respectively, had different stress levels at delivery that were statistically significant for the BL6 mice. Even so, the BL6 mice cohoused with rats had significantly increased FCM concentrations, indicative of higher stress levels, as compared to (1) BL6 mice housed alone or (2) BL6 mice at delivery. In contrast to their elevated stress levels, the attractiveness for contextual cues associated with mouse-mouse social interaction (DSI CPP) even increased in rat-cohoused BL6 mice, albeit nonsignificantly. Thus, cohousing BL6 mice and rats did not impair a behavioral assay in BL6 mice that had proved to be sensitive to handling stress by humans in our laboratory. SD rats cohoused with BL6- or CD1 mice and CD1 mice cohoused with SD rats showed DSI CPP that was not different from our previously published data on SD rats and BL6 mice of the Jackson- or NIH substrain obtained in the absence of cohousing. Our findings suggest that the effect of cohousing rats and mice under the conditions described above on their stress levels as opposed to their behavior might be less clearcut than generally assumed and might be overriden by conditions that cannot be controlled, i.e., different deliveries. Our findings can help to use research animal housing resources, which usually are limited, more efficiently.
ARTICLE | doi:10.20944/preprints202308.0779.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: bile acids; colesevelam; enterohepatic circulation; liver; humanized mouse model
Online: 10 August 2023 (04:16:37 CEST)
Bile acids (BAs) and their signalling pathways have been identified as therapeutic targets for liver and metabolic diseases. We generated Cyp2c70-/- (KO) mice that are not able to convert chenodeoxycholic acid into rodent-specific muricholic acids (MCAs) and, hence, possess a more hydrophobic, human-like BA pool. Recently, we have shown that KO mice display cholangiopathic features with development of liver fibrosis. The aim of this study was to determine whether BA sequestration modulates liver pathology in Western type-diet (WTD)-fed KO mice. The BA sequestrant colesevelam was mixed into the WTD (2% w/w) of male Cyp2c70+/+ (WT) and KO mice and the effects were evaluated after 3 weeks of treatment. Colesevelam increased fecal BA excretion in WT and KO mice and reduced the hydrophobicity of biliary BAs in KO mice. Colesevelam ameliorated diet-induced hepatic steatosis in WT mice, whereas KO mice were resistant to diet-induced steatosis and BA sequestration had no additional effects on liver fat content. Total cholesterol concentrations in livers of colesevelam-treated WT and KO mice were significantly lower than those of untreated controls. Of particular note, colesevelam treatment normalized plasma levels of liver damage markers in KO mice and markedly decreased hepatic mRNA levels of fibrogenesis-related genes in KO mice. Lastly, colesevelam did not affect glucose excursions and insulin sensitivity in WT or KO mice. Our data show that BA sequestration ameliorates liver pathology in Cyp2c70-/- mice with a human-like bile acid composition without affecting insulin sensitivity.
REVIEW | doi:10.20944/preprints202111.0458.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: NAD+; aging; yeast; C. elegans; mouse; rat; monkey; human
Online: 24 November 2021 (13:10:22 CET)
Nicotinamide adenine dinucleotide (NAD+) is an essential molecule involved in various metabolic reactions, acting as an electron donor in the electron transport chain and as a co-factor for NAD+-dependent enzymes. In the early 2000s, reports that NAD+ declines with aging introduced the notion that NAD+ metabolism is globally and progressively impaired with time. Since then, NAD+ became an attractive target for potential pharmacological therapies aiming to boost NAD+ levels to promote vitality and protect against age-related diseases. This review summarizes and discusses a collection of studies that report the levels of NAD+ with aging in different species (i.e., yeast, C. elegans, rat, mouse, monkey, and human) to determine whether the notion that overall NAD+ levels decrease with aging stands true. We find that despite systematic claims of overall changes in NAD+ levels with aging, the evidence to support it is very limited and often restricted to a single tissue or cell type. This is particularly true in humans, where the development of NAD+ levels during aging is still poorly characterized. There is a need for much larger, preferably longitudinal, studies aimed to assess how NAD+ levels develop with aging in various tissues. This will strengthen our conclusions on NAD+ during aging and should provide a foundation for better pharmacological targeting of relevant tissues.
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: nNOS; Temporal lobe epilepsy; Interneuron; Synaptic transmission; Mouse models
Online: 25 November 2020 (10:19:05 CET)
Excitation-inhibition imbalance of GABAergic interneurons is predisposed to develop chronic temporal lobe epilepsy (TLE). We have previously shown that virtually every neuronal nitric oxide synthase (nNOS)-positive cell is a GABAergic inhibitory interneuron in the denate gyrus. The present study was designed to quantify the number of nNOS-containing hilar interneurons using stereology in pilocapine- and kainic acid (KA)-exposed transgenic adult mice that expressed GFP under the nNOS promoter. In addition, we studied the properties of miniature excitatory postsynaptic current (mEPSC) and paired-pulse response ratio (PPR) of evoked EPSC in nNOS interneurons using whole cell recording techniques. Results showed that there were fewer nNOS-immunoreactive interneurons of chronically epileptic animals. Importantly, patch-clamp recordings revealed reduction in mEPSC frequency, indicating diminished global excitatory input. In contrast, PPR of evoked EPSC following the granule cell layer stimulation was increased in epileptic animals suggesting reduced neurotransmitter release from granule cell input. In summary, we propose that impaired excitatory drive onto hippocampal nNOS interneurons may be implicated in the development of refractory epilepsy.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: BE4; CRISPR-Cas9; Tyr; cytosine base editing; mouse model
Online: 30 December 2019 (11:16:30 CET)
Most human genetic disease arises from point mutations. These genetic diseases can theoretically be corrected by gene therapy but clinic practice is still far from mature. Nearly half of the pathogenic single-nucleotide polymorphisms (SNPs) are caused by G:C>A:T or T:A>C:G base changes. The best current methods to repair these changes are by base editing without footprint using recently developed CRISPR-Cas9 technology by David Liu’s lab. These base editing methods have been confirmed with precision and efficiency in cultured mammalian cells, but it is barely confirmed and the efficiency is still very low. Animal models are important in dissecting pathogenic mechanism for human genetic diseases and efficacy testing of base correction in vivo. Cytidine base editor BE4 is a newly developed version of cytidine base editing system that converts cytidine (C) to uridine (U) in cultured mammalian cells but has not been proven in vivo. In this study, we have tested this system in cells to inactivate GFP gene and in mice by introducing single-base substitution that leads to a stop codon in tyrosinase gene. High percentage albino coat-colored mice were obtained from black coat-colored donor zygotes after pronuclei microinjection. Sequencing results showed that expected base changes were obtained with high precision and efficiency (56.25%). There are no off-targeting events identified in predicted off-target sites. Results confirm BE4 system can work in vivo with high precision and efficacy, and has great potentials in clinic to repair human genetic mutations.
ARTICLE | doi:10.20944/preprints201808.0314.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: MELK inhibitor; OTS167; LC-MS/MS; Pharmacokinetics, mouse serum
Online: 17 August 2018 (15:15:12 CEST)
A novel, rapid and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the evaluation of OTS167 pharmacokinetics in mouse serum. SN-38 was optimized to be selected as the internal standard. Chromatographic separation was performed on a BDS Hypersil C18 column (100 x 2.1 mm, 5 µm) using gradient elution with mobile phase solvent A as water containing 0.1% formic acid and solvent B as acetonitrile containing 0.1% formic acid. The analysis was carried out using multiple reaction monitoring (MRM) with a triple-quadrupole mass spectrometer operated in the positive electrospray ionization mode. Mass transitions of 487.2 > 348.0 and 393.2 > 349.2 were monitored for OTS167 and SN-38 respectively. The standard calibration curve demonstrated high linearity at a range of 5-1000 ng/mL, with a coefficient of determination (r2) ≥ 0.996. The accuracy for OTS167 ranged from 92.3% to 102.2% and the precision was ≤ 12.7%. Recovery was consistent at about 83% to 89%. No significant matrix effect was observed. This method was successfully applied to monitor the pharmacokinetic profiles in mice over 24 h after ingestion of 5 mg/kg of OTS167. Maximum serum concentrations (3197 ng/mL) of OTS167 was observed at 1.67 hour after OTS167 ingestion via garage at 5 mg/kg and area under the curve (AUC) was 28579 h*ng/mL, suggesting that OTS167 can be quickly absorbed after oral administration.
COMMUNICATION | doi:10.20944/preprints202307.0721.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: mouse HER2; monoclonal antibody; cell-based Immunization and screening; CBIS
Online: 12 July 2023 (03:20:12 CEST)
Overexpression of human epidermal growth factor receptor 2 (HER2) in breast cancer is an important target of monoclonal antibody (mAb) therapy such as trastuzumab. Due to the development of trastuzumab-deruxtecan, an antibody-drug conjugate, the targetable HER2-positive breast cancer patients have been expanded. To evaluate developing modalities using anti-HER2 mAbs, reliable preclinical mouse models are required. Therefore, sensitive mAbs against mouse HER2 (mHER2) should be established. This study developed mHER2 mAbs using the Cell-Based Immunization and Screening (CBIS) method. The established anti-mHER2 mAbs, H2Mab-300 (rat IgG2b, kappa) and H2Mab-304 (rat IgG1, kappa), reacted with mHER2-overexpressed Chinese hamster ovary-K1 (CHO/mHER2) and endogenously mHER2-expressed cell line, NMuMG (a mouse mammary gland epithelial cell) by flow cytometry. Furthermore, these mAbs never recognized mHER2-knockout NMuMG cells. The kinetic analysis using flow cytometry indicated that the dissociation constant (KD) of H2Mab-300 and H2Mab-304 for CHO/mHER2 was 1.2 × 10−9 M and 1.7 × 10−9 M, respectively. The KD of H2Mab-300 and H2Mab-304 for NMuMG was 4.9 × 10−10 M and 9.0 × 10−10 M, respectively. These results indicated that H2Mab-300 and H2Mab-304 could apply to the detection of mHER2 using flow cytometry and may be useful to obtain the proof of concept in preclinical studies.
ARTICLE | doi:10.20944/preprints202306.1906.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: Neurodevelopmental disorders; KCNMA1; cochlear functionality; acoustic startle; genetic mouse models
Online: 27 June 2023 (12:37:59 CEST)
Hyperacusis, i.e., an increased sensitivity to sounds, is described in several neurodevelopmental disorders (NDDs), including Fragile X Syndrome (FXS). The mechanisms underlying hyperacusis in FXS are still largely unknown and effective therapies are lacking. Big conductance calci-um-activated potassium (BKCa) channels have been proposed as a therapeutic target to treat several behavioral disturbances in FXS preclinical models, but their role in mediating their au-ditory alterations has not been specifically addressed. Furthermore, studies on the acoustic phe-notypes of FXS animal models have mostly focused on central rather than peripheral auditory pathways. Here we provided an extensive characterization of the peripheral auditory phenotype of the Fmr1-knockout (KO) mouse model of FXS at adulthood. We also assessed whether the acute administration of Chlorzoxazone, a BKCa agonist, could rescue the auditory abnormalities of mutant mice. Fmr1-KO mice both at 3 and 6 months showed a hyperacusis-like startle pheno-type with paradoxically reduced auditory brainstem responses associated with a loss of ribbon synapses in the inner hair cells (IHCs). BKCa expression was markedly reduced in the IHCs of KO mice, but only at 6 months, when Chlorzoxazone rescued mutant auditory dysfunction. Our findings highlight the age-dependent and progressive contribution of peripheral mechanisms and BKCa channels to hyperacusis in FXS, suggesting a novel therapeutic target to treat auditory dysfunction in NDDs.
COMMUNICATION | doi:10.20944/preprints202305.0641.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: mouse EGFR; monoclonal antibody; Cell-Based Immunization and Screening; CBIS
Online: 9 May 2023 (10:42:31 CEST)
The Epidermal Growth Factor Receptor (EGFR) overexpression or its mutation mediates the sustaining proliferative signaling in cancers. Human EGFR-targeting monoclonal antibody (mAb) therapy such as cetuximab has been approved for clinical use in patients with colorectal cancers and head and neck squamous cell carcinomas. A reliable preclinical mouse model is essential to further develop the mAb therapy against EGFR. However, a mAb against mouse EGFR (mEGFR) for flow cytometry has not been established. In this study, we developed a specific and sensitive mAb for mEGFR using the Cell-Based Immunization and Screening (CBIS) method. The established anti-mEGFR mAb, EMab-300 (rat IgG1, kappa) reacted with mEGFR-overexpressed Chinese hamster ovary-K1 (CHO/mEGFR) and endogenously mEGFR-expressed cell lines, including NMuMG (a mouse mammary gland epithelial cell) and Lewis lung carcinoma cells by flow cytometry. The kinetic analysis using flow cytometry indicated that the dissociation constant (KD) of EMab-300 for CHO/mEGFR and NMuMG was 4.3 × 10−8 M and 1.9 × 10−8 M, respectively. These results indicated that EMab-300 applies to the detection of mEGFR by flow cytometry, and is expected in the use of preclinical study.
ARTICLE | doi:10.20944/preprints202211.0071.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mouse CCR3; monoclonal antibody; epitope mapping; alanine scanning; flow cytometry
Online: 3 November 2022 (07:35:45 CET)
The CC chemokine receptor 3 (CCR3) is a receptor for CC chemokines, including CCL5/RANTES, CCL7/MCP-3, and CCL11/eotaxin. CCR3 is expressed on the surface of eosinophils, basophils, a subset of Th2 lymphocytes, mast cells, and airway epithelial cells. CCR3 and its ligands are involved in airway hyperresponsiveness in allergic asthma, ocular allergy, and cancers. Therefore, CCR3 is an attractive target for those therapies. Previously, anti-mouse CCR3 (mCCR3) monoclonal antibodies (mAbs), C3Mab-3 (rat IgG2a, kappa), and C3Mab-4 (rat IgG2a, kappa) were developed using the Cell-Based Immunization and Screening (CBIS) method. In this study, the binding epitope of these mAbs was investigated using flow cytometry. The CCR3 extracellular domain-substituted mutant analysis showed that C3Mab-3, C3Mab-4, and a commercially available mAb (J073E5) recognized the N-terminal region (amino acids 1–38) of mCCR3. Next, the alanine scanning was conducted in the N-terminal region. The results revealed that Ala2, Phe3, Asn4, and Thr5 of mCCR3 are involved in C3Mab-3 binding, whereas Ala2, Phe3, and Thr5 are essential to C3Mab-4 binding, and Ala2 and Phe3 are crucial to J073E5 binding. These results reveal the involvement of the N-terminus of mCCR3 in the recognition of C3Mab-3, C3Mab-4, and J073E5.
COMMUNICATION | doi:10.20944/preprints202304.0032.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: mouse CD39; monoclonal antibody; the Cell-Based Immunization and Screening; CBIS
Online: 4 April 2023 (02:29:25 CEST)
CD39 is involved in adenosine metabolism through conversion of extracellular ATP to adenosine. Because extracellular adenosine plays a critical role in the immune suppression of tumor microenvironment, the inhibition of CD39 activity by monoclonal antibodies (mAbs) is one of the important strategies for tumor therapy. In this study, we developed specific and sensitive mAbs for mouse CD39 (mCD39) using the Cell-Based Immunization and Screening (CBIS) method. The established anti-mCD39 mAbs, which were established by the CBIS method including C39Mab-1 (rat IgG2a, kappa) and C39Mab-2 (rat IgG2a, lambda), reacted with not only mCD39-overexpressed Chinese hamster ovary-K1 (CHO/mCD39) but also endogenously mCD39-expressed cell lines, such as L1210 (mouse lymphocytic leukemia) and J774-1 (mouse macrophage-like) cell lines through flow cytometry. Kinetic analyses using flow cytometry indicated that the dissociation constant (KD) of C39Mab-1 and C39Mab-2 for CHO/mCD39 was 7.3 × 10−9 M and 5.5 × 10−9 M, respectively. KD of C39Mab-1 and C39Mab-2 for L1210 was 3.3 × 10−9 M and 3.6 × 10−10 M, respectively. Furthermore, C39Mab-1 could detect the lysate of CHO/mCD39 by western blot analysis. These results indicate that C39Mab-1 and C39Mab-2 are useful for the detection of mCD39 in many functional studies.
ARTICLE | doi:10.20944/preprints202204.0150.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Ttc21a; Ttc21b; mouse knock-out; jaw; facial bone; viscerocranium; Hh signaling
Online: 16 April 2022 (03:36:54 CEST)
Ciliopathies are genetic syndromes that link skeletal dysplasias to dysfunction of primary cilia. Primary cilia are sensory organelles synthesized by intraflagellar transport (IFT) - A and B complexes, which traffic protein cargo along a microtubular core. We have reported that deletion of IFT-A gene, Thm2, together with a null allele of its paralog, Thm1, causes a small skeleton with small mandible or micrognathia in juvenile mice. Using micro-computed tomography, here we quantify the craniofacial defects of Thm2-/-;Thm1aln/- triple allele mutant mice. At postnatal day 14, triple allele mutant mice exhibit micrognathia, maxillary hypoplasia, and a decreased facial angle due to shortened maxilla, premaxilla, and nasal bones, reflecting altered development of facial anterior-posterior elements. In contrast, other ciliopathy-related craniofacial defects, such as cleft lip and/or palate, hypo-/hypertelorism, broad nasal bridge, craniosynostosis, and facial asymmetry, were not observed, suggesting development of the facial transverse dimension is intact. Calvarial-derived osteoblasts of triple allele mutant mice showed reduced bone formation in vitro that was ameliorated by Hedgehog agonist, SAG. Together, these data indicate that Thm2 and Thm1 genetically interact to regulate bone formation and sculpting of the postnatal face. The triple allele mutant mice present as a novel model to study craniofacial bone development.
ARTICLE | doi:10.20944/preprints202202.0223.v1
Subject: Biology And Life Sciences, Virology Keywords: endogenous retroviruses; HERV-K; mouse mammary tumor virus; dolutegravir; 4T1 cells
Online: 18 February 2022 (05:10:41 CET)
Increasing evidence points to the role of endogenous retroviruses (ERVs) in driving cancer cell proliferation. The purpose of this study was to explore the possibility of repurposing antiretroviral agents to inhibit ERVs as a new approach in cancer treatment. We found that an integrase strand-transfer inhibitor, dolutegravir (DTG), effectively inhibited the proliferation of multiple cancer cell lines and its antiproliferative potency was positively correlated with the expression levels of the human endogenous retrovirus type K (HERV-K). DTG inhibited the expression of HERV-K in multiple human cancer cell lines and the mouse mammary tumor virus (MMTV) in the murine 4T1 mammary cancer cell line. We chose the fast-growing BT-20 cell line as a model to study the in vitro antiproliferative mechanisms of DTG. BT-20 cells overexpressing both HERV-K env and pol genes became more resistant to DTG than cells transduced with vector alone. Knockdown of HERV-K also increased DTG resistance of BT-20 cells. The antiproliferative effect of DTG correlated with enhanced expression of E-cadherin and reduction in cell motility and invasiveness. Surprisingly, DTG stimulated expression of the env gene of MMTV in vivo and promoted metastasis of 4T1 tumor cells to the lungs. Taken together, our data support a role of ERVs in tumor development and encourage further search for antiretroviral agents to treat malignancies in which endogenous retroviruses are active.
REVIEW | doi:10.20944/preprints202201.0117.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: G protein-coupled receptor; mouse models; skin cancer; UVR; drug; network
Online: 10 January 2022 (13:41:08 CET)
G protein-coupled receptors (GPCRs) serve prominent roles in melanocyte lineage physiology, with an impact at all stages of development, as well as on mature melanocyte functions. GPCR ligands are present in the skin and regulate melanocyte homeostasis, including pigmentation. The role of GPCRs in the regulation of pigmentation and, consequently, protection against external aggression, such as ultraviolet radiation, has long been established. However, evidence of new functions of GPCRs directly in melanomagenesis has been highlighted in recent years. GPCRs are coupled, through their intracellular domains, to heterotrimeric G proteins, which induce cellular signaling through various pathways. Such signaling modulates essential cellular processes of melanomagenesis, such as proliferation and migration. GPCR-associated signaling in melanoma can be activated by the binding of paracrine factors to their receptors or directly by activating mutations. In this review, we present melanoma-associated alterations of GPCRs and their downstream signaling and discuss the various preclinical models used to evaluate new therapeutic approaches against GPCR activity in melanoma. Recent striking advances in our understanding of the structure, function, and regulation of GPCRs will undoubtedly broaden treatment options in melanoma in the future.
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: B cell; V(D)J recombination; mouse model; NHEJ; DNA repair
Online: 12 June 2020 (07:53:17 CEST)
Non-homologous end joining (NHEJ) is the main DNA repair mechanism for the repair of double strand breaks (DSBs) throughout the course of the cell cycle. DSBs are generated in developing B and T lymphocytes during V(D)J recombination to increase the repertoire of B and T cell receptors. DSBs are also generated during the class switch recombination (CSR) process in mature B lymphocytes, providing distinct effector functions of antibody heavy chain constant regions. Thus, NHEJ is important for both V(D)J recombination and CSR. NHEJ comprises core Ku70 and Ku80 subunits that form the Ku heterodimer, which binds DSBs and promotes the recruitment of accessory factors (e.g., DNA-PKcs, Artemis, PAXX, Mri) and downstream core factors (XLF, Lig4 and XRCC4). In recent decades, new NHEJ proteins have been reported, increasing complexity of this molecular pathway. Numerous in vivo mouse models have been generated and characterized to identify the interplay of NHEJ factors and their role in development of adaptive immune system. This review summarizes the currently available mouse models lacking one or several NHEJ factors, with a particular focus on early B cell development. We also underline genetic interactions and redundancy in the NHEJ pathway in mice.
ARTICLE | doi:10.20944/preprints201903.0286.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: lung adenocarcinoma; KRAS; MYC; ERBB; mouse models of cancer; RNA-SEQ
Online: 30 March 2019 (06:41:07 CET)
Inducible genetically defined mouse models of cancer uniquely facilitate the investigation of early events in cancer progression, however there are valid concerns about the ability of such models to faithfully recapitulate human disease. We developed an inducible mouse model of progressive lung adenocarcinoma (LuAd) that combines sporadic activation of oncogenic KRasG12D with modest overexpression of c-MYC (KM model). Histological examination revealed a highly reproducible transition from adenoma to locally invasive adenocarcinoma within 6 weeks of oncogene activation. Laser-capture microdissection coupled with RNA-SEQ was employed to determine transcriptional changes associated with tumour progression. Upregulated genes were triaged for relevance to human LuAd using datasets from Oncomine and cBioportal. Selected genes were validated by RNAi screening in human lung cancer cell lines and examined for association with lung cancer patient overall survival using KMplot.com. Depletion of progression-associated genes resulted in pronounced viability and/or cell migration defects in human lung cancer cells. Progression-associated genes moreover exhibited strong associations with overall survival, specifically in human lung adenocarcinoma, but not in squamous cell carcinoma. The KM mouse model faithfully recapitulates key molecular events in human lung cancer and is a useful tool for mechanistic interrogation of LuAd progression.
ARTICLE | doi:10.20944/preprints201809.0082.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: atherosclerosis; coronary aortic disease; gene set enrichment analysis; heart disease; Apoe mouse; transcriptomics; RNA-seq analysis; pathway enrichment analysis; mouse; precision medicine; New Zealand White rabbit
Online: 5 September 2018 (04:49:40 CEST)
The central promise of personalized medicine is individualized treatments that target molecular mechanisms underlying the physiological changes and symptoms arising from disease. We demonstrate a bioinformatics analysis pipeline as a proof-of-principle to test the feasibility and practicality of comparative transcriptomics to classify two of the most popular in vivo diet-induced models of coronary atherosclerosis, apolipoprotein E null mice and New Zealand White rabbits. Transcriptomics analyses indicate the two models extensively share dysregulated genes albeit with some unique pathways. For instance, while both models have alterations in the mitochondrion, the biochemical pathway analysis revealed, Complex IV in the electron transfer chain is higher in mice, whereas the rest of the electron transfer chain components are higher in the rabbits. Several fatty acids anabolic pathways are expressed higher in mice, whereas fatty acids and lipids degradation pathways are higher in rabbits. This reflects the differences between two translational models of atherosclerosis. This study validates transcriptome analysis as a potential method to precisely identify altered cellular and molecular pathways in atherosclerotic disease, which can be used to individualize treatment even in the absence of genetic data.
ARTICLE | doi:10.20944/preprints202305.2269.v1
Subject: Medicine And Pharmacology, Epidemiology And Infectious Diseases Keywords: EBV oncogenes; LMP1; Nasopharyngeal; gastric carcinomas; mouse model; tumor suppression and prevention
Online: 31 May 2023 (14:42:00 CEST)
Abstract: The study aimed to investigate the antitumor efficacy of anti-LMP1 antibodies in EBV-positive nasopharyngeal and stomach cell lines and xenograft models. The study also exam-ined the NF-κB expression and cell cycle activation of NPC serum exosome-associated LMP1. An-ti-LMP1 antibody treatment before or during cell implantation prevented tumor growth in nude mice. A small dose of antibodies resulted in complete tumor regression for at least three months af-ter the tumors had grown in size. The consumption of antigen-antibody complexes by tumor cells limited tumor growth. In vitro experiments showed that anti-LMP1 antibodies killed EBV-positive NPC- or GC-derived epithelial cell lines and EBV-positive human B cell lines but not EBV-negative cell lines. Treatment with anti-LMP1 reduced NF-κB expression in cells. The animal model experi-ments showed anti-LMP1 inhibited and prevented NPC- or GC-derived tumor growth. The results suggest that LMP1 antibody immunotherapy could cure nasopharyngeal cancer, EBV-positive gastric carcinoma, and EBV-associated lymphomas. However, further validation of these findings is required through human clinical trials.
ARTICLE | doi:10.20944/preprints202302.0433.v1
Subject: Medicine And Pharmacology, Anesthesiology And Pain Medicine Keywords: ECLS; ECMO; animal model; rodent; rat; mouse; hamster; CPB; in-vivo; oxygenator
Online: 27 February 2023 (02:41:38 CET)
The survival rate of extracorporeal life support (ECLS) remains overall at 60 %. Research and development is slow, partly due to the lack of sophisticated experimental models. This publication introduces a dedicated rodent oxygenator (“RatOx”) and shows preliminary in vitro classification tests. The RatOx has an adaptable fiber module size for various rodent models. Gas transfer performance over the fiber module for different blood flows and fiber module sizes were tested according to DIN EN ISO 7199.At the maximum possible amount of effective fiber surface and a blood flow of 100 ml/min, the oxygenator performance has been tested to a maximum of 6.27 ml O2/min and 8.2 ml CO2/min, respectively. The priming volume for this the largest fiber module is 5.4 ml, while the smallest possible configuration with a single fiber mat layer has 1.1 ml of priming volume. The novel RatOx ECLS system has been evaluated in-vitro to comply to a high degree with all predefined functionality criteria for rodent sized animal models. We intend for the RatOx to become a standard testing platform for scientific studies on ECLS therapy and technology.
ARTICLE | doi:10.20944/preprints202212.0189.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mouse CCR9, monoclonal antibody, epitope mapping, alanine scanning, enzyme-linked immunosorbent assay
Online: 12 December 2022 (03:54:29 CET)
C-C chemokine receptor 9 (CCR9) is a receptor for C-C-chemokine ligand 25 (CCL25). CCR9 is crucial in the chemotaxis of immune cells and inflammatory responses. Moreover, CCR9 is highly expressed in tumors including several solid tumors and T-cell acute lymphoblastic leukemia. Several preclinical studies have shown that anti-CCR9 monoclonal antibodies (mAbs) exert antitumor activity. Therefore, CCR9 is an attractive target for tumor therapy. In this study, we conducted the epitope mapping of an anti-mouse CCR9 (mCCR9) mAb, C9Mab-24 (rat IgG2a, kappa), using a 1 × alanine (1 × Ala) and 2 × alanine (2 × Ala)-substitution method via enzyme-linked immunosorbent assay. We first performed the 1 × Ala-substitution method using one alanine-substituted peptides of the mCCR9 N-terminus (amino acids 1-19). C9Mab-24 did not recognize two peptides (F14A and F17A), indicating that Phe14 and Phe17 are critical for C9Mab-24-binding to mCCR9. Furthermore, we conducted the 2 × Ala-substitution method using two consecutive alanine-substituted peptides of the mCCR9 N-terminus, and showed that C9Mab-24 did not react with four peptides (M13A–F14A, F14A–D15A, D16A–F17A, and F17A–S18A), indicating that 13-MFDDFS-18 is involved in C9Mab-24-binding to mCCR9. Overall, combining, the 1 × Ala or 2 × Ala scanning methods could be useful for understanding for target-antibody interaction.
ARTICLE | doi:10.20944/preprints202212.0170.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: SonoCloud; GL261 mouse model; ultrasound-mediated drug delivery; glioblastoma; immune checkpoint inhibitors
Online: 9 December 2022 (02:59:28 CET)
Therapeutic antibodies targeting immune checkpoints have shown limited efficacy in clinical trials in glioblastoma (GBM) patients. Ultrasound-mediated blood-brain barrier opening (UMBO) using low-intensity pulsed ultrasound improved drug delivery to the brain. We explored the safety and the efficacy of UMBO plus immune checkpoint inhibitors in preclinical models of GBM. A Blood-brain barrier (BBB) opening was performed using a 1 MHz preclinical ultrasound system in combination with 10µl/g microbubbles. Brain penetration of immune checkpoint inhibitors was determined, and immune cell populations were evaluated using flow cytometry. The impact of repeated treatments on survival was determined. In syngeneic GL261-bearing immunocompetent mice, we showed that UMBO safely and repeatedly open the BBB. BBB opening was confirmed visually and microscopically using Evans’s blue dye and magnetic resonance imaging. UMBO plus anti-PDL-1 was associated with a significant improvement of the overall survival compared to anti-PD-L1 alone. Using mass spectroscopy, we showed that the penetration of therapeutic antibodies can be increased when delivered intravenously compared to non-sonicated brains. Furthermore, we observed an enhancement of activated microglia percentage when combined with anti-PD-L1. Here, we report that the combination of UMBO and anti-PD-L1 dramatically increases GL261-bearing mice's survival compared to their counterparts treated with anti-PD-L1 alone. Our study highlights the BBB as a limitation to overcome to increase the efficacy of anti-PD-L1 in GBM and supports clinical trials combining UMBO and in GBM patients.
ARTICLE | doi:10.20944/preprints202203.0260.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: thyroid cancer; PTC; BRAFV600E; mouse model; miRNA; extracellular vesicles; heterogeneity; se-quencing
Online: 18 March 2022 (03:53:48 CET)
Papillary thyroid cancer (PTC) is the most common endocrine malignancy which diagnosis and recurrences still challenge clinicians. New perspectives to overcome those issues could come from the study of extracellular vesicles (EVs) populations and content. Here, we aimed to elucidate the heterogeneity of EVs circulating in tumor and the changes in their microRNA content during cancer progression. Using a mouse model expressing BRAFV600E, we isolated and characterized EVs from thyroid tissue by ultracentrifugations and elucidated their microRNA content by small RNA sequencing. Cellular origin of EVs was investigated by ExoView and that of deregulated EV-microRNA by qPCR on FACS-sorted cell populations. We found that PTC released more EVs bearing epithelial and immune markers, as compared to healthy thyroid, and that changes in EV-microRNAs abundance were mainly due to their deregulated expression in thyrocytes. Pathway analysis showed that the more abundant EV-microRNAs could impact on immune processes. Altogether, our work provides a full description of in vivo-derived EVs produced by, and within, normal and cancerous thyroid. We elucidated the global EV-microRNAs signature, the dynamic loading of microRNAs in EVs upon BRAFV600E induction, and their cellular origin. Thyroid tumor-derived EV-microRNAs could support the establishment of a permissive immune microenvironment.
ARTICLE | doi:10.20944/preprints202107.0050.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: mouse mammary tumor virus 1; human breast cancer 2; risk factor 3
Online: 2 July 2021 (11:34:47 CEST)
(1) Background: Mouse-mammary tumor virus (MMTV) might play a role in the etiology of some breast cancers in humans. The purpose of our study was to identify MMTV DNA sequences in breast tissue samples from breast cancer patients operated in our regional center from Romania. (2) Methods: We have selected 75 patients with non-metastatic breast cancer treated with curative intent and searched with PCR the MMTV-like DNA sequence in the breast cancer tissue and normal breast tissue obtained from the same patients. (3) Results: None of the examined samples was positive for MMTV-like target sequences on PCR. (4) Conclusions: We could not prove that MMTV plays a role in the etiology of breast cancer in our patient group. This finding is similar to findings of other geographically related research groups and might be due to the fact that only the Mus musculus domesticus mouse species was proven to carry infectious MMTV, but not the Mus musculus musculus species, which is specific to South-Eastern Europe and some parts of Asia.
ARTICLE | doi:10.20944/preprints201912.0368.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: V(D)J recombination; vAbl cells; B lymphocytes; mouse genetics; genetic interaction
Online: 29 December 2019 (04:36:17 CET)
DNA double-strand breaks (DSBs) trigger the Ataxia telangiectasia mutated (ATM)-dependent DNA damage response (DDR), which consists of histone H2AX, MDC1, RNF168, 53BP1, PTIP, RIF1, Rev7, and Shieldin. Early stages of B and T lymphocyte development are dependent on recombination activating gene (RAG)-induced DSBs that form the basis for further V(D)J recombination. Non-homologous end joining (NHEJ) pathway factors recognize, process, and ligate DSBs. Based on numerous loss-of-function studies, DDR factors were thought to be dispensable for the V(D)J recombination. In particular, mice lacking Mediator of DNA Damage Checkpoint Protein 1(MDC1) possessed nearly wild-type levels of mature B and T lymphocytes in the spleen, thymus, and bone marrow. NHEJ factor XRCC4-like factor (XLF)/Cernunnos is functionally redundant with ATM, histone H2AX, and p53-binding protein 1 (53BP1) during the lymphocyte development in mice. Here, we genetically inactivated MDC1, XLF, or both MDC1 and XLF in murine vAbl pro-B cell lines and, using chromosomally integrated substrates, demonstrated that MDC1 stimulates the V(D)J recombination in cells lacking XLF. Moreover, combined inactivation of MDC1 and XLF in mice resulted in synthetic lethality. Together, these findings suggest that MDC1 and XLF are functionally redundant during the mouse development, in general, and the V(D)J recombination, in particular.
REVIEW | doi:10.20944/preprints201904.0127.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: PTEN; PI3K; cancer predisposition syndromes; targeted therapies; mouse models of human cancer
Online: 10 April 2019 (10:37:43 CEST)
The PI3K-AKT-mTOR signal transduction pathway regulates a variety of biological processes including cell growth, cell cycle progression and proliferation, cellular metabolism and cytoskeleton reorganization. Fine-tuning of the PI3K pathway signaling output is essential for the maintenance of tissue homeostasis and uncontrolled activation of this cascade leads to a number of human pathologies including cancer. Inactivation of the tumour suppressor phosphatase PTEN and/or activating mutations in the proto-typical lipid kinase PI3K have emerged as some of the most frequent events associated with human cancer and as a result the PI3K pathway has become a highly sought-after target for cancer therapies. In this review we summarize the essential role of the PTEN-PI3K axis in controlling cellular behaviors by modulating activation of key proto-oncogenic molecular nodes and functional targets. Further, we highlight important functional redundancies and peculiarities of these two critical enzymes that over the last few decades have become a central part of the cancer research field and have instructed hundreds of pre-clinical and clinical trials to better cancer treatments.
ARTICLE | doi:10.20944/preprints201808.0169.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: metabolic syndrome; diabetes mellitus; obesity, lactobacilli; bifidobacteria; glucose; macrophages; inflammation; mouse model
Online: 8 August 2018 (14:27:20 CEST)
Introduction. The use of probiotics demonstrate efficacy against obesity and metabolic syndrome (MetS). Detection effective probiotic strains for hyperglycemia and immunity associated with is important task. The aim of the study was to evaluate an influence of Lactobacillus casei IMV B-7280 separately and composition L. casei IMV B-7280 / Bifidobacterium animalis VKB / B. animalis VKL on the levels of blood glucose and immunity in obese mice. Meterials and methods. Obesity was induced by fat-enriched diet (FED) in male BALB/c mice. Obese mice were transferred to standard diet and received per os probiotic strains daily during 10 days. We measured tumor necrosis factor-a (TNF-a) in blood serum using enzyme-linked immunosorbent assay and functional activity of peritoneal exudate macrophages (PEMs). Glucose levels in blood was defined with glucometer. Results. We ascertained that all probiotic strains induced reducing mice weight and visceral fat, normalization of TNF-a production and functional activity of PEMs. Treatment with L. casei IMV B-7280 was associated with decreasing blood glucose levels. No normalization of glucose and TNF-a levels in obese mice, transferred to standard diet without probiotic treatment, although we revealed decreasing their weight and visceral fat and partial recover of functional activity of PEMs. Conclusions. Probiotic strain L. casei IMV B-7280 (separately) and composition L. casei IMV B-7280 / B. animalis VKB / B. animalis VKL can re-equilibrate metabolic and inflammation indices in mouse obesity model. L. casei IMV B-7280 alone was more efficient in decreasing glucose levels than composition of strains.
ARTICLE | doi:10.20944/preprints201803.0149.v1
Subject: Biology And Life Sciences, Virology Keywords: influenza; H1N1; mouse adaptation; deep sequencing; polymerase; PA; PB1; defective viral genomes
Online: 19 March 2018 (08:59:26 CET)
Mice are not natural hosts for influenza A viruses (IAVs), but they are useful models for studying antiviral immune responses and pathogenesis. Serial passage of IAV in mice invariably causes the emergence of adaptive mutations and increased virulence. Typically, mouse-adaptation studies are conducted in inbred laboratory strains BALB/c and C57BL/6, which have defects in the antiviral Mx1 gene that results in increased susceptibility to infection and disease severity. Here, we report the adaptation of IAV reference strain A/California/07/2009(H1N1) (a.k.a. CA/07) in outbred Swiss Webster mice. Serial passage led to increased virulence and lung titers, and dissemination of the virus to brains. We adapted a deep-sequencing protocol to identify and enumerate adaptive mutations across all genome segments. Among mutations that emerged during mouse-adaptation, we focused on amino acid substitutions in polymerase subunits: polymerase basic-1 (PB1) T156A and F740L, and polymerase acidic (PA) E349G. These mutations were evaluated singly and in combination in minigenome replicon assays, which revealed that PA E349G increased polymerase activity. By selectively engineering these three adaptive PB1 and PA mutations into the parental CA/07 strain, we demonstrated that adaptive mutations in polymerase subunits decreased the production of defective viral genome segments with internal deletions, and dramatically increased the release of infectious virions from mouse cells. Together, these findings increase our understanding of the contribution of polymerase subunits to successful host adaptation.
ARTICLE | doi:10.20944/preprints202310.0085.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: autism; gut dysfunction; gut motility; gut transit; mouse model; Neuroligin-3; video-imaging
Online: 3 October 2023 (08:57:54 CEST)
Individuals with autism often experience gastrointestinal issues but the cause is unknown. Many gene mutations that modify neuronal synapse function are associated with autism and therefore may impact the enteric nervous system that regulates gastrointestinal function. A missense mutation in the Nlgn3 gene encoding the cell adhesion protein, Neuroligin-3, was identified in two brothers with autism who both experienced severe gastrointestinal dysfunction. Mice expressing this mutation (Nlgn3R451C mice) are a well-studied preclinical model of autism and show autism-relevant characteristics, including impaired social interaction and communication, as well as repetitive behaviour. We previously showed colonic dysmotility in response to GABAergic inhibition and increased myenteric neuronal numbers in the small intestine in Nlgn3R451C mice bred on a mixed genetic background. Here we show that gut dysfunction is a persistent phenotype of the Nlgn3 R451C mutation in mice backcrossed onto a C57BL/6 background. We report that Nlgn3R451C mice show faster gastrointestinal transit in vivo and have longer small intestines compared to wild-types due to a reduction in smooth muscle tone. In Nlgn3R451C mice, we observed a decrease in resting jejunal diameter and neurally-regulated dysmotility as well as shorter durations of contractile complexes in the ileum. In Nlgn3R451C mouse colons, short contractions were inhibited to a greater extent by the GABAA antagonist, gabazine, compared to wild-type mice. Inhibition of nitric oxide synthesis decreased the frequency of contractile complexes in the jejunum, but not the ileum, in both wild-type and Nlgn3R451C mice. These findings demonstrate that changes in enteric nervous system function contribute to gastrointestinal dysmotility in mice expressing the autism-associated R451C missense mutation in the Neuroligin-3 protein.
ARTICLE | doi:10.20944/preprints202104.0101.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Mouse-Human Chimeric Antibody; Immunotherapy; Infectious diseases; Histoplasmosis; Paracoccidioidomycosis; Histoplasma capsulatum; Paracoccidioides lutzii
Online: 5 April 2021 (11:33:24 CEST)
Heat shock proteins (Hsps) are highly conserved molecules that are constitutively expressed and upregulated in response to physiological stress conditions. These immunogenic chaperones can have essential functions in fungi, particularly in dimorphic pathogens. Histoplasma capsulatum and Paracoccidioides species are dimorphic fungi that are the causative agents of histoplasmosis and paracoccidioidomycosis, respectively, which are systemic mycoses with significant rates of morbidity and mortality. Current treatment consists of long-term antifungal agents, and there is an urgent need for new therapeutic approaches with higher efficacy, lower toxicity, better biodistribution and improved selectivity. We engineered an immunoglobulin G1 (IgG1) isotype chimeric mouse-human monoclonal antibody, titled ch-MAb 4E12, from the parental IgG2a MAb 4E12, a monoclonal antibody to H. capsulatum Hsp60 that is protective in experimental histoplasmosis and paracoccidioidomycosis models elicited by H. capsulatum var. capsulatum and Paracoccidioides lutzii, respectively. The ch-MAb 4E12 increased phagolysosomal fusion and enhanced the yeasts uptake by PMA differentiated human THP1 macrophage cells in vitro. At low concentrations, the chimeric antibody significantly reduced the pulmonary and splenic fungal burden compared to an irrelevant antibody or no treatment. These results are the first to show that a chimeric mouse-human antibody can modify infection caused by dimorphic fungi.
ARTICLE | doi:10.20944/preprints202102.0132.v1
Subject: Medicine And Pharmacology, Ophthalmology Keywords: multidrug resistance protein 4; ATP-binding cassette (ABC) transporters; aging; retina; mouse; electroretinogram
Online: 4 February 2021 (10:58:06 CET)
Multidrug resistance protein 4 (MRP4) is an energy-dependent membrane transporter that is responsible for cellular efflux of a broad range of xenobiotics and physiological substrates. In this trial, we aimed to investigate the co-effects of aging and MRP4 deficiency using gene expression microarray and morphological and electrophysiological analyses of the mouse retina. Mrp4-knockout (null) mice and wild-type (WT) mice were reared in the same condition to 8–12 wk (young) or 45–55 wk (aged). Microarray analysis identified 186 differently expressed genes from the retinas of aged Mrp4-null mice as compared to that from aged WT mice, and subsequence gene ontology and KEGG pathway analyses showed that differently expressed genes were related to lens, eye development, vision, and transcellular barrier function that are involved in metabolic pathways or viral infection pathways. No significant change in thickness was observed for each retinal layer among young/aged WT mice and young/aged Mrp4-null mice. Moreover, immunohistochemical analyses of retinal cell type did not exhibit an overt change in the cellular morphology or distribution among the 4 age/genotype groups, and the electroretinogram responses showed no significant differences in the amplitude or the latency between aged WT mice and aged Mrp4-null mice. Aging would be an insufficient stress to cause some damage to the retina in the presence of MRP4 deficiency.
ARTICLE | doi:10.20944/preprints202009.0159.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: Nicotine; Cotinine; Corticosterone; LCMS; Sex; C57BL/6J mouse; CYP2A5; Plasma Levels; Subcutaneous Injection
Online: 7 September 2020 (08:08:54 CEST)
We assessed if there were any sex-related differences in the ability of nicotine to increase plasma corticosterone secretion after single or repeated nicotine administration. For single-dose studies, male and female mice were habituated to the test room for 1 h and injected with saline or nicotine (0.25 or 1 mg/kg, s.c.). In repeated-dosing studies, mice were injected with saline or nicotine (1 mg/kg, s.c.) once daily for six days, and, on day 7, received nicotine (1 mg/kg, s.c.). The mice were euthanized 15 min later, and trunk blood was collected for the measurement of corticosterone, nicotine, and cotinine. Our results showed that saline or nicotine each significantly increased plasma corticosterone levels in both male and female mice, with a greater response in female mice. Plasma corticosterone levels were increased in male but not female mice after repeated compared to single nicotine administration. The level of cotinine, a biomarker of nicotine use, was significantly higher in female than in male mice. Taken together, these novel findings suggest that female mice responded to nicotine and stress of handling more than male mice and provide for the first-time quantitative data on the male-female differences in nicotine-induced elevations of corticosterone and of cotinine.
ARTICLE | doi:10.20944/preprints201809.0569.v1
Subject: Biology And Life Sciences, Biophysics Keywords: magnetic hyperthermia, magnetic nanoparticles (MNP), doxorubicin (DOX), NucAnt (N6L), breast cancer, mouse model
Online: 28 September 2018 (13:29:53 CEST)
Doxorubicin (DOX) is a frequently used chemotherapeutic drug for breast cancer, but its site specificity and local internalization into tumor cells is rather low. In this paper we conjugated magnetic nanoparticles (MNPs) with DOX and/or a pseudopeptide NucAnt (N6L) as modality to enhance DOX-induced antitumor effects in breast cancer cells (BT474). In this context, we determined cellular uptake of MNP formulations, analyzed cell viability and expression of apoptotic and cell cycle proteins after magnetic hyperthermia (43°C, 1 h) in vivo and in vitro. We have shown that i) the presence of N6L on the surface of DOX-functionalized MNPs increases their internalization into a target cells and potentiates the cytotoxic potential of the anticancer drug, ii) in combination with hyperthermia, DOX functionalized MNPs influence the expression of apoptotic and cell cycle proteins, and also favors tumor regression in vivo. Our data show that intratumoral application of DOX coupled MNPs is able to overcome biological barriers to chemotherapeutic drugs, enabling them to penetrate into the target cells. Combined with hyperthermia these MNPs can be an effective method in enhancing the localised delivery and penetration of DOX into breast cancer cells.
ARTICLE | doi:10.20944/preprints201806.0340.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: T-regulatory cells, immune regulation, Foxp3, PPARγ, autoimmune diabetes, NOD mouse, Thiazolidinediones, ciglitazone.
Online: 22 June 2018 (09:33:32 CEST)
Immunomodulation as means of immunotherapy has been studied in major research and clinical laboratories for many years. T-Regulatory (Treg) cell therapy is one of the modulator used in immunotherapy approaches. Similarly, nuclear receptor peroxisome proliferator activated receptor gamma (PPARγ) has extensively been shown to play a role as an immuno-modulator during inflammation. Given their mutual roles in downregulating the immune response, current study examined the influence of PPARγ ligands i.e thiazolidinedione (TZD) class of drugs on Foxp3 expression and possible crosstalk between PPARγ and nTreg cells of NOD and NOR mice. Results showed that TZD drug, ciglitazone and natural ligand of PPARγ 15d-prostaglandin downregulated Foxp3 expression in activated nTreg cells from both NOD and NOR mice. Interestingly, addition of the PPARγ inhibitor, GW9662 further downregulated Foxp3 expression in these cells from both mice. We also found that PPARγ ligands negatively regulate Foxp3 expression in activated nTreg cells via PPARγ-independant mechanism(s). These results demonstrate that both natural and synthetic PPARγ ligands capable of suppressing Foxp3 expression in activated nTreg cells of NOD and NOR mice. This may suggest that the effect of PPARγ ligands in modulating Foxp3 expression in activated nTreg cells is different from their reported effects on effector T cells. Given the capability to suppress foxp3 gene, it is possible to be tested as immunomodulators in cancer-related studies.
ARTICLE | doi:10.20944/preprints201711.0110.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Fluorescent reporter; E2-Crimson; mouse embryonic stem cells; knock-in; in vivo imaging
Online: 16 November 2017 (17:46:53 CET)
Far-red fluorescent reporter genes can be used for tracking cells non-invasively in vivo using fluorescence imaging. Here, we investigate the effectiveness of the far-red fluorescent protein, E2-Crimson (E2C), for tracking mouse embryonic cells (mESCs) in vivo following subcutaneous administration into mice. Using a knock-in strategy, we introduced E2C into the Rosa26 locus of an E14-Bra-GFP mESC line, and after confirming that the E2C had no obvious effect on the phenotype of the mESCs, we injected them into mice and imaged them over 9 days. The results showed that fluorescence intensity was weak, and cells could only be detected when injected at high densities. Furthermore, intensity peaked on day 4 and then started to decrease, despite the fact that tumour volume continued to increase beyond day 4. Histopathological analysis showed that although E2C fluorescence could barely be detected in vivo at day 9, analysis of frozen sections indicated that all mESCs within the tumours continued to express E2C. We hypothesise that the decrease in fluorescence intensity in vivo was probably due to the fact that the mESC tumours became more vascular with time, thus leading to increased absorbance of E2C fluorescence by haemoglobin. We conclude that the E2C reporter has limited use for tracking cells in vivo, at least when introduced as a single copy into the Rosa26 locus.
ARTICLE | doi:10.20944/preprints202307.0169.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: HER2; breast cancer; monoclonal antibody; antitumor activities; mouse xenograft model; antibody-dependent cellular cytotoxicity
Online: 4 July 2023 (09:38:15 CEST)
Two monoclonal antibodies (mAbs) against human epidermal growth factor receptor 2 (HER2), trastuzumab and pertuzumab, were clinically approved. We previously developed a highly sensitive and specific anti-HER2 mAb, H2Mab-139 (mouse IgG1, kappa). In this study, we produced a defucosylated IgG2a version of anti‑HER2 mAb (H2Mab-139-mG2a-f) to enhance ADCC-mediated antitumor activity. H2Mab-139-mG2a-f exhibits a high binding affinity in flow cytometry with the dissociation constant (KD) determined to be 3.9 × 10‑9 M and 7.7 × 10‑9 M against HER2‑overexpressed Chinese hamster ovary (CHO)-K1 (CHO/HER2) and HER2-positive BT-474 cells, respectively. Moreover, we showed that H2Mab-139-mG2a-f exerted ADCC and complement-dependent cytotoxicity against CHO/HER2 and BT-474 cells in vitro and exhibited potent antitumor activities in the xenograft models. These results indicated that H2Mab-139-mG2a-f exerts antitumor effects against HER2-positive human breast cancers and could be useful for an antibody treatment regimen for HER2-positive human cancers.
ARTICLE | doi:10.20944/preprints202305.0075.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: non-alcoholic fatty liver disease; non-alcoholic steatohepatitis; hepatocellular carcinoma; cirrhosis; fibrosis; mouse model
Online: 2 May 2023 (09:00:10 CEST)
Non-alcoholic steatohepatitis (NASH), which is the most severe manifestation of non-alcoholic fatty liver disease (NAFLD), has been recognized as a major hepatocellular carcinoma (HCC) catalyst. However, the molecular mechanism of NAFLD-NASH-HCC sequence remains unclear and a specific and effective treatment for NASH has not yet been established. The progress in this field depends on the availability of reliable preclinical models which show the steady progress to NASH, liver cirrhosis, and HCC. However, most of NASH mouse models that have been described to date develop NASH generally for more than 24 weeks and there is an uncertainty of HCC development. To overcome such shortcomings of experimental NASH studies, we established a novel NASH-HCC mouse model with very high reproducibility, generality, and convenience. We treated male C57BL/6J mice with a newly developed choline-deficient and methionine-restricted high-fat diet (CDMRHFD) for 60 weeks. Treatment of CDMRHFD for 3 weeks revealed marked steatosis, lobular inflammation, and fibrosis, histologically diagnosed as NASH. Liver cirrhosis was observed in all mice with 36-week treatment. Liver nodule emerged at 12 weeks of the treatment, and diameter >2 mm liver tumors developed in all mice at 24 weeks of the treatment. In conclusion, our rapidly progressive and highly reproducible NASH-liver cirrhosis-HCC model is helpful for preclinical development and research on the pathogenesis of human NAFLD-NASH-HCC. Our mouse model would be useful for the development of novel chemistry for NASH-HCC-targeted therapies or HCC prevention strategies.
ARTICLE | doi:10.20944/preprints202105.0247.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: IgLON; Lsamp; Ntm; Opcml; Negr1; alternative promoter; cell adhesion molecules; embryonic mouse brain; pallium
Online: 11 May 2021 (14:22:01 CEST)
The members of the IgLON superfamily of cell adhesion molecules facilitate fundamental cellular communication during brain development, maintain functional brain circuitry, and are associated with several neuropsychiatric disorders. Usage of alternative promoter-specific 1a and 1b mRNA isoforms in Lsamp, Opcml, Ntm and the single promoter of Negr1 in the mouse and human brain has been previously described. To determine the precise spatiotemporal expression dynamics of Lsamp, Opcml, Ntm isoforms and Negr1, in the developing brain, we generated isoform-specific RNA probes and carried out in situ hybridization in the developing (embryonic, E10.5, 13.5, 17; post natal, P0) and adult mouse brains. We show that promoter-specific expression of IgLONs is established early during pallial development (at E10.5), where it remains throughout its differentiation through adulthood. In the diencephalon, midbrain and hindbrain, strong expression patterns are initiated a few days later and begin fading after birth, being only faintly expressed during adulthood. Thus, the expression of specific IgLONs in the developing brain may provide the means for regionally specific functionality as well as for specific regional vulnerabilities. The current study will therefore improve the understanding of how IgLON genes are implicated in the development of neuropsychiatric disorders.
ARTICLE | doi:10.20944/preprints201809.0091.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: pheomelanin; mouse; benzothiazole; benzothiazine; pro-oxidant activity; melanoma; reactive oxygen species; ultraviolet-A; glutathione
Online: 5 September 2018 (08:10:43 CEST)
It is known that eumelanin (EM) is photoprotective while pheomelanin (PM) is phototoxic. A recent study using a mouse model demonstrated that PM produces reactive oxygen species (ROS) that cause DNA damage and eventually lead to melanomagenesis. A biochemical study showed that PM possesses a pro-oxidant activity. PM consists of benzothiazine (BT) and benzothiazole (BZ) moieties, the former being transformed to the latter by heat or light. In this study, we compared the effects of ultraviolet A (UVA) irradiation using synthetic PMs with different BT to BZ ratios and using various coat color mouse hairs. We found that UVA irradiation of BZ-PM increased glutathione (GSH) consumption and generated more H2O2 than UVA irradiation of BT-PM. Non-irradiated controls did not exhibit strong pro-oxidant activities. Upon UVA irradiation, yellow mouse hairs oxidized GSH and produced H2O2 faster than black or albino mouse hairs. Next, to examine the mechanism of the pro-oxidant activity of BT-PM and BZ-PM, we examined the pro-oxidant activities of 7-(2-amino-2-carboxyethyl)-dihydro-1,4-benzothiazine-3-carboxylic acid (DHBTCA) and 6-(2-amino-2-carboxyethyl)-4-hydroxybenzothiazole (BZ-AA) as BT and BZ monomers, respectively. Their pro-oxidant activities were similar, but a large difference was seen in the effects of ROS scavengers, which suggests that the redox reactions may proceed via singlet oxygen in BZ-AA and via superoxide anions in DHBTCA. These results show that UVA enhances the pro-oxidant activity of PM, in particular BZ-PM.
ARTICLE | doi:10.20944/preprints202311.0210.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Brucella abortus; 3-AT; catalase inhibitor; intracellular growth; immune response; RAW 264.7 cell; ICR mouse
Online: 3 November 2023 (05:07:39 CET)
Catalase, an antioxidant enzyme widely produced in mammalian cells and bacteria, is crucial in mitigating oxidative stress in a hostile environment. This function enhances the intracellular survivability of various intracellular growth pathogens, including Brucella abortus. In this study, to determine whether the inhibition of catalase can inhibit the intracellular growth of Brucella (B.) abortus, we employed 3-amino-1,2,4-triazole (3-AT), a catalase inhibitor, in both RAW 264.7 macrophage cells and an ICR mouse model during Brucella infection. The intracellular growth assay indicated that 3-AT exerts growth-inhibitory effects on B. abortus within macrophages. Aside from that, it contributes to the accumulation of reactive oxygen species and the formation of nitric oxide. Notably, 3-AT diminishes the activation of the nucleus transcription factor (NF-κB) and modulates cytokine secretion within infected cells. In our mouse model, the administration of 3-AT reduced B. abortus proliferation within the spleen and liver of infected mice. This reduction was accompanied by a diminished immune response to infection, as indicated by lowered levels of TNF-α, IL-6, IL-10, and altered CD4+/CD8+ T-cell ratio. These results suggest the protective and immunomodulatory effects of 3-AT treatment against Brucella infection.
ARTICLE | doi:10.20944/preprints202308.1756.v2
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: PDPN; lung cancer; glioblastoma; monoclonal antibody; antitumor activities; mouse xenograft model; antibody-dependent cellular cytotoxicity
Online: 20 October 2023 (12:26:35 CEST)
We previously developed a highly sensitive and specific anti-PDPN mAb, LpMab-23 (mouse IgG1, kappa). In this study, we produced a humanized IgG1 version (humLpMab-23) and its defucosylated form (humLpMab-23-f) of an anti‑PDPN mAb to potentiate the ADCC activity. The humLpMab-23 could recognize PDPN‑overexpressed Chinese hamster ovary (CHO)-K1 (CHO/PDPN) and PDPN-positive PC-10 and LN319 cells by flow cytometry. Furthermore, we found that humLpMab-23-f exerted ADCC and complement-dependent cytotoxicity against CHO/PDPN, PC-10 and LN319 cells in vitro and exhibited potent antitumor activities in the xenograft models. These results indicated that humLpMab-23-f could be useful for an antibody treatment regimen for PDPN-positive human cancers.
ARTICLE | doi:10.20944/preprints202304.0619.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: wound healing; natural compound; excisional mouse model; molecular docking; dynamic molecular; caryophyllene; cytokines; digital histology
Online: 20 April 2023 (07:42:54 CEST)
Dysregulation of the arsenal of cells, growth factors, cytokines, proteases, and proteins involved in wound healing (WH), could delay the healing process. Plants and plant-derived molecules (PDMs) have been used as medicines for skin wounds. This study aimed to select and evaluate the pro-healing capacity of PMDs. Thirty-three PDMs and 10 therapeutic targets (TTs) were chosen for molecular docking and PDMs: aristolochic acid (AA), α-copaene, selinenes, β-caryophyllene (BC), and BCoxide, and TTs: metalloproteinase (MMP) 3, MMP13, and tumor necrosis factor (TNF α) for molecular dynamics. The bests inhibitor was AA, but because of its toxicity, BC and BCoxide were chosen for evaluation in HaCat cells and BALB/c mice excisional model. Both compounds were not toxic, and higher percentages of lesion area closure (LAC) were induced by BC treatment (p<0.05). All mice healed; however, an initial delay of LAC was induced by 0.05, 0.1% BCoxide, 0.1% BC, and allantoin. At the end of treatment, lower numbers of mast cells, level of cellular infiltrates (except 1% BCoxide and 0.05, 0.5%BC), epidermal thickness tendency (except 0.1, 0.5% BCoxide), and higher values of SC-thickness, and collagen fibers only by 0.5% BC treatment compared with untreated control (p<0.05) were observed. Our results show that BC is a promising multitarget candidate for wound healing treatment and optimization campaigns.
REVIEW | doi:10.20944/preprints201804.0295.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: bone metastasis; tissue engineering; mesenchymal stem cells; osteoclast; osteoblast; dormancy; mouse models; circulating tumor cell
Online: 23 April 2018 (12:35:38 CEST)
Metastasis is the leading cause of cancer-related death and drives patient morbidity as well as healthcare costs. For several cancers, breast and prostate in particular, bone is the primary site of metastasis. Efforts to treat bone metastases have been stymied by a lack of models to study the progression and cellular players and signaling pathways driving bone metastasis. In this review, we examine the newly described and classic models of bone metastasis. Through the use of current in vivo, microfluidic and in silico computational models bone metastasis models we may eventually understand how cells escape the primary tumor and how these circulating tumor cells then home to and colonize the bone marrow. Further, future models may uncover how cell enter and escape dormancy to develop into overt metastases. Recreating the metastatic process will lead to the discovery of therapeutic targets for disrupting and treating bone metastasis.
ARTICLE | doi:10.20944/preprints201803.0236.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Keywords: TMV, plant vaccine, génital herpes, HSV-2, gD, VP16, GFP, mouse model genital herpes
Online: 28 March 2018 (09:18:30 CEST)
A B S T R A C T Genital herpes disease is caused mainly by herpes simplex virus type 2 (HSV-2), which is sexually transmitted with a high prevalence in both developed and developing countries. No vaccine is currently available against genital herpes. In this study, we introduced and expressed two genes encoding HSV-2 glycoprotein D (gD) and VP16 protein and a GFP marker gene (control) in tobacco seedlings. Positive plant infection was assessed through characteristic tobacco mosaic virus disease symptoms on leaves and by monitoring the fluorescence emitted by the expressed GFP protein. Expression of the HSV-gD2 and VP16 antigens was verified by RT-PCR, ELISA and Western blot. As a proof of concept, the immunogenicity and the protection ability of the plant produced gD antigen was tested in a mouse model of genital herpes and compared to gD antigen produced in a mammalian expression system. This showed that the plant-gD preparation, when used in combination with a CpG oligodeoxynucleotide as adjuvant, was highly immunogenic and capable of inducing complete immunity to lethal vaginal HSV-2 challenge in mice. Thus, the data presented here may have implications for the development of a production system for highly immunogenic plant-based HSV-2 vaccine antigens.
ARTICLE | doi:10.20944/preprints201803.0041.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: mouse node; Kupffer’s vesicle; primary cilium; asymmetry; symmetry breaking; bilateral symmetry; cell chirality; centriole; centrosome
Online: 6 March 2018 (04:57:46 CET)
In zebrafish inner ear, hair cell orientation in anterior and posterior maculae of the embryonic otic vesicle is different (about 30–40 degrees): this is rather unusual in planar polarity mechanism of action, instead suggests that kinocilia may be rotationally polarized. In mice node, the innermost monociliated cells generate a left-ward fluid flow sensed by the immotile primary cilia of Left peri-nodal cells: the Nodal signaling pathway is then expressed asymmetrically, in the Left lateral plate mesoderm, breaking symmetry in visceral organs (situs solitus); however, Right peri-nodal cells also, if artificially excited by a right-ward flow, break symmetry and activate the Nodal cascade, though inverting visceral organ asymmetry (situs inversus); surprisingly, peri-nodal cells prove to be adept at distinguishing flow directionality. Recently, in the Kupffer vesicle (the zebrafish laterality organ), chiral primary cilia orientation has been described: primary cilia, in the left and right side, are symmetrically oriented, showing a mirror average divergence of about 15–20 degrees from the midline. This finding, taken together with the mirror behavior of mouse perinodal cells and zebrafish hair cells, champions the idea of primary cilia enantiomerism.
ARTICLE | doi:10.20944/preprints202308.1392.v1
Subject: Biology And Life Sciences, Virology Keywords: COVID-19; SARS-CoV-2; C57BL/6; mouse-adapt; Two-photon excitation microscopy; in vivo imaging
Online: 18 August 2023 (16:02:12 CEST)
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) often causes severe viral pneumonia, especially among older individuals and those with underlying health conditions. The C57BL/6 mouse is widely used to develop mouse models of obesity, diabetes, hypertension, and immune disorders, conditions that are associated with increased risk of severe COVID-19. Although many studies using these mouse models have examined the pathogenicity of SARS-CoV-2, COVID-19 pathogenesis remains poorly understood. In vivo imaging analysis using two-photon excitation microscopy is useful for elucidating the pathology of COVID-19, providing pathological insights that are not available from conventional histological analysis. However, there is no reporter SARS-CoV-2 that demonstrates pathogenicity in C57BL/6 mice and emits sufficient light intensity for two-photon in vivo imaging. Here, we generated SARS-CoV-2 expressing the fluorescent protein Venus to facilitate in vivo pathological studies using C57BL/6 mouse models. We generated a mouse-adapted strain of SARS-CoV-2, by performing sequential lung-to-lung passages in BALB/c mice, followed by in C57BL/6 mice. We observed that the C57BL/6-adapted SARS-CoV-2 (named MASCV2-p25) replicated efficiently in the lungs of C57BL/6 mice, causing fatal pneumonia. Histopathologic analysis revealed severe inflammation and infiltration of immune cells in the lungs of MASCV2-p25-infected C57BL/6J mice, not unlike that observed in COVID-19 patients with severe pneumonia. Subsequently, we generated a mouse-adapted reporter SARS-CoV-2 (named MASCV-Venus-p9) by inserting the fluorescent gene Venus into MASCV2-p25, and sequential lung-to-lung passages in C57BL/6 mice. C57BL/6 mice infected with MASCV2-Venus-p9 exhibited severe pneumonia similar to that induced by MASCV2-p25. In addition, two-photon excitation microscopy of the lungs of the infected C57BL/6J mice showed that the infected cells emitted sufficient levels of fluorescence for easy observation. These findings suggest that MASCV2-Venus-p9 will be useful for two photon in vivo imaging studies of the pathogenesis of severe COVID-19 and for the development of therapeutic agents for severe pneumonia.
REVIEW | doi:10.20944/preprints202306.2170.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: N-acetylcysteine; amino acid supplements; L-arginine; Duchenne muscular dystrophy; mdx mouse; osmolytes; supportive therapy; taurine
Online: 30 June 2023 (07:13:00 CEST)
Duchenne muscular dystrophy (DMD), the severest form of muscular dystrophy, is characterized by progressive muscle weakness with fatal outcome most often before the fourth decade of life. Despite recent addition of molecular treatments, DMD remains a disease without a cure, and the need persists for the development of supportive therapies aimed to help improve patients’ quality of life. This review focusses on the therapeutical potential of amino acid and derivative supplements, summarizing results obtained in preclinical studies in the murine disease model. Several promising compounds have come forward, with L-arginine, N-acetylcysteine and taurine featuring among the most intensively investigated. Beneficial effects include improved muscle function and reduced muscle fiber necrosis and reduced inflammatory and oxidative damage to muscle tissues, however mild side effects have also surfaced. In order to identify amino acid formulae that are safe and of true benefit to DMD patients, more explorative, placebo-controlled and long-term clinical trials need to be conducted, documenting therapeutic outcomes.
ARTICLE | doi:10.20944/preprints202305.1144.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: bovine collagen hydrolysate; gallium phthalocyanine; pigmented melanoma; normal keratocytes and fibroblasts; mouse embryonal fibroblasts; photodynamic therapy
Online: 16 May 2023 (09:46:10 CEST)
Collagen has been accepted in drug delivery structures due to its biocompatible chemical, physicochemical and curative actions. The study aims to evaluate the effects of a bovine collagen hydrolysate (Clg) on the main photophysical and photodynamic properties of a new gallium (III) phthalocyanine (GaPc). The absorbance of GaPc and the conjugate GaPc-Clg showed a decrease of the intensive Q-band (681 nm) and a blue shift of the maximum (678 nm) with loss of UV-band (354 nm) for 40 mg/mL Clg. The fluorescence of GaPc was evaluated with strong emission peak at 694 nm (exc: 615 nm) which was lower for GaPc-Clg (691 nm). The quantum yield of 0.23 was obtained for GaPc which was reduced for GaPc-Clg (0.012). Photo- and dark cytotoxicity was studied by NRU-assay on pigmented melanoma cells (SH-4) and normal cell lines (BJ and HaCaT). The results suggested a slight reduction of cytotoxicity for the conjugate but almost double for the selectivity index (SI: 0.71 vs. 1.49 for HaCaT cells). The study showed that bovine collagen hydrolysate can lower the PDT activity of a powerful photosensitizer with phototherapeutic index: 819 to 360, but also minimized its dark toxicity as a positive effect in the photodynamic treatment.
ARTICLE | doi:10.20944/preprints202208.0106.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: DPAGT1; Congenital Disorders of Glycosylation; sensitized chemical mutagenesis screen; mouse genetics; inherited retinal disease; ER Stress
Online: 4 August 2022 (07:08:13 CEST)
Congenital Disorders of Glycosylation (CDG) are a heterogenous group of primarily autosomal recessive mendelian diseases caused by disruptions in the synthesis of lipid linked oligosaccha-rides and their transfer to proteins. CDGs affect multiple organ systems and vary in presentation, even within families. Here we describe a chemically induced mouse mutant, tvrm76, with early onset photoreceptor degeneration. The recessive mutation was mapped to Chromosome 9 and as-sociated with a missense mutation in the Dpagt1 gene encoding UDP-N-acetyl-D-glucosamine:dolichyl-phosphate N-acetyl-D-glucosaminephosphotransferase (EC 184.108.40.206). The mutation is predicted to cause a substitution of aspartic acid with glycine at residue 166 of DPAGT1. Increased expression of Ddit3, and elevated levels of HSPA5 (BiP) sug-gest the presence of early-onset endoplasmic reticulum (ER) stress. These changes were associated with induction of photoreceptor apoptosis in tvrm76 retinas. Mutations in human DPAGT1 cause Myasthenic Syndrome 13 and severe forms of Congenital Disorder of Glycosylation Type Ij. In contrast, Dpagt1tvrm76 homozygous mice present with congenital photoreceptor degeneration without overt muscle or muscular junction involvement. Our results suggest the possibility of DPAGT1 mutations in human patients that present primarily with retinitis pigmentosa with little or no muscle disease. Variants in DPAGT1 should be considered when evaluating cases of non-syndromic retinal degeneration.
ARTICLE | doi:10.20944/preprints202309.1417.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: R-RAS2; RAS; GTPases; chronic lymphocytic leukemia; B-CLL; mouse model; ibrutinib; venetoclax; new therapies; cancer treatment
Online: 21 September 2023 (12:04:56 CEST)
B-cell chronic lymphocytic leukemia (B-CLL) is the most common type of leukemia in the Western world. Mutations in different genes, such as TP53 and ATM, and deletions in specific chromosomal regions, including 11q or 17p, have been associated with a worse prognosis for the disease. Recent research from our group has demonstrated that, contrary to the usual cancer development process through missense mutations, B-CLL is driven by the overexpression of the small GTPase RRAS2 in its wild-type form, without activating mutations. While some mouse models of this disease have been developed to date and are commonly used in B-CLL research, they come with various disadvantages, such as a long waiting period until the leukemia fully develops, the need for cell engraftment, or, in some cases, a failure to replicate the alterations found in human patients. We have recently introduced Rosa26-RRAS2fl/flxmb1-Cre as a new mouse model of B-CLL with full disease penetrance. In this work, we have validated this mouse model as a novel tool for the development of new therapies for B-CLL by testing two of the most widely applied targeted agents: ibrutinib and venetoclax. This also paves the way for the development of new targeted agents against R-RAS2 itself, an approach that has not yet been explored in clinical practice.
ARTICLE | doi:10.20944/preprints202308.1226.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: neuroinflammation; neurodegeneration; hippocampus; glial cells; cell-cell interactions; clasmatodendrosis; amyloid plaques; Aβ-aggregates; transgenic mouse; confocal microscopy
Online: 17 August 2023 (09:37:09 CEST)
The term neuroinflammation defines the reactions of astrocytes and microglia to alterations in homeostasis in the diseased central nervous system (CNS), the exacerbation of which contributes to the neurodegenerative effects of Alzheimer's disease (AD). Local environmental conditions, such as the presence of proinflammatory molecules, mechanical properties of the extracellular matrix (ECM) and local cell-cell interactions, are determinants of glial cell phenotypes. In AD, the load of the cytotoxic/proinflammatory amyloid β peptide (Aβ) is a microenvironmental component increasingly growing in the CNS, imposing time-evolving challenges on resident cells. This study aimed at investigating the temporal and spatial variations of the effects produced by this process on astrocytes and microglia, either directly or by interfering in their interactions. Ex vivo confocal analyses of hippocampal sections from the mouse model TgCRND8 at different ages have shown that overproduction of Aβ peptide induced early and time persistent disassembly of functional astroglia syncytium and promoted a senile phenotype of reactive microglia, hindering Aβ clearance. In the late stages of disease, these patterns were altered in the presence of Aβ-plaques, surrounded by typically reactive astrocytes and microglia. Morphofunctional characterization of peri-plaque gliosis revealed a direct contribution of astrocytes in plaque buildup that might result in shielding Aβ-peptide cytotoxicity and, as a side effect, in exacerbating neuroinflammation.
ARTICLE | doi:10.20944/preprints202307.0097.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Intracerebellar Hemorrhage; Mouse Model; Nitric Oxide Synthase; Oxidative stress Markers; Neuronal Nitric Oxide Synthase; GABA and glutamate transporters
Online: 3 July 2023 (13:26:33 CEST)
The underlying mechanisms of secondary neuronal damage following intracerebellar hemorrhage are not yet clear. We aimed to study the possible mechanisms in the mediation of secondary neuronal damage following intracerebellar hemorrhage. ICbH was induced by collagenase type VII-S into mice in 2 phases (n=24/phase): 12 in control group, 12 in day 1 group, 12 in day 3 group and another 12 in day 7 group. All mice underwent locomotor assessment and subsequently sacrificed on day 1, day 3 and day 7 respectively. Cerebellum from phase one and phase two were taken to study morphological, immunohistochemistry and oxidative stress respectively. Mice behavior disturbed following ICbH at day 3 and y 7 as compared with control. Besides, NO increased-on day 1 post induction and suppressed on day 3 and 7. Expressions of SOD, CAT, nNOS, GPX1 and COX-2 were significantly raised on day 3. Morphological studies of the perihaematoma region and tissue showed neuronal damage occurred from day 1 onwards, peaked on day 3 and continued day 7. NO and expression of genes be correlating with morphological changes. Briefly, NO and oxidative stress has an important role in the cascade of secondary neuronal damage of the perihematomal region of ICbH.
REVIEW | doi:10.20944/preprints202207.0242.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: mouse models; Plasmodium; Adaptive immunity; Innate immunity; T cells; B cells; Macrphages; Neutrophils; Antibodies; Cytokines; parasite control; immunopathogensis
Online: 18 July 2022 (03:12:30 CEST)
Malaria comprises a spectrum of disease syndromes and the immune system is a major participant in malarial disease. This is particularly true in relation to the immune responses elicited against blood stages of Plasmodium-parasites that are responsible for the pathogenesis of infection. Mouse models of malaria are commonly used to dissect the immune mechanisms underlying disease. While no one mouse model of Plasmodium infection completely recapitulates all the features of malaria in humans, collectively the existing models are invaluable for defining the events that lead to the immunopathogenesis of malaria. Here we review the different mouse models of Plasmodium infection that are available, and highlight some of the main contributions these models have made with regards to identifying immune mechanisms of parasite control and the immunopathogenesis of malaria.
ARTICLE | doi:10.20944/preprints202103.0659.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Chondrogenesis; chondrocyte; cell differentiation; C3H10T1/2; high density culture; mouse em-bryo; epigenetic signals; DNA methylation; 5-azacytidine
Online: 26 March 2021 (11:24:08 CET)
The aim of this study was to investigate the role of DNA methylation in the regulation of in vitro and in vivo cartilage formation. Based on the data of an RNA chip-assay performed on chondrifying BMP2-overexpressing C3H10T1/2 cells, the relative expression of Tet1 (tet methylcytosine dioxygenase 1), Dnmt3a (DNA methyltransferase 3) and Ogt (O-linked N-acetylglucosamine transferase) genes was examined with RT-qPCR in mouse cell-line based and primary micromass cultures. RNA probes for in situ hybridization were used on frozen sections of 15-day-old mouse embryos. DNA methylation was inhibited with 5-azacytidine during culturing. We found very strong but gradually decreasing expression of Tet1 throughout the entire course of in vitro cartilage differentiation along with strong signals in the cartilaginous embryonic skeleton. Dnmt3a and Ogt expressions did not show significant changes with RT-qPCR and gave weak in situ hybridization signals. Inhibition of DNA methylation applied during early stages of differentiation reduced cartilage-specific gene expression and cartilage formation. In contrast, it had stimulatory effect when added to differentiated chondrocytes. Our results indicate that the DNA demethylation-inducing Tet1 is a significant epigenetic factor of chondrogenesis, and inhibition of DNA methylation exerts distinct effects in different phases of in vitro cartilage formation.
ARTICLE | doi:10.20944/preprints201903.0244.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: vertebrate retina, mouse, zebrafish, two-photon microscopy, biosensor, activity probes, visual stimulus-evoked activity, laser-evoked retinal activity
Online: 26 March 2019 (14:01:49 CET)
Two-photon imaging of light stimulus-evoked neuronal activity has been used to study all neuron classes in the vertebrate retina, from the photoreceptors to the retinal ganglion cells. Clearly, the ability to study retinal circuits down to the level of single synapses or zoomed out at the level of complete populations of neurons, has been a major asset in our understanding of this beautiful circuit. In this chapter, we discuss the possibilities and pitfalls of using an all-optical approach in this highly light-sensitive part of the brain.
ARTICLE | doi:10.20944/preprints202106.0659.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Neonatal mortality; husbandry practices; cage inspection; pup counting method; social environment; cannibalistic behaviour; asynchrony breeding; mouse welfare, 3Rs principle.
Online: 28 June 2021 (14:02:37 CEST)
Perinatal mortality is a major issue in laboratory mouse breeding. We compared a counting method using daily checks (DAILY_CHECK) with a method combining daily checks with detailed video analyses to detect cannibalisms (VIDEO_TRACK) for estimating the number of C57BL/6 pups born, died and weaned in 193 litters from trios with (TRIO-OVERLAP) or without (TRIO-NO_OVERLAP) the presence of another litter. Linear mixed models were used at litter level. To understand if cannibalism was associated with active killing (infanticide), we analysed VIDEO_TRACK recordings of 109 litters from TRIO-OVERLAP, TRIO-NO_OVERLAP or SOLO (single dams). We used Kaplan-Meier method and logistic regression at pup level. For DAILY_CHECK, the mean litter size was 35% smaller than for VIDEO_TRACK (P<0.0001) and the number of dead pups was twice lower (P<0.0001). The risk of pup loss was higher for TRIO-OVERLAP than TRIO-NO_OVERLAP (P<0.0001). A high number of pup losses occurred between birth and the first cage checking. Analyses of VIDEO_TRACK data indicated that pups were clearly dead at the start of most of the cannibalism events and infanticide was rare. As most pups die and disappear before the first cage check, many breeding facilities are likely to be unaware of their real rates of mouse pup mortality.
DATA DESCRIPTOR | doi:10.20944/preprints202305.0963.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Ferroptosis; proteomics; LC-MS/MS; mouse embryonic fibroblasts; Pfa1; cell death; glutathione peroxidase 4; erastin; ML210; L-Buthionine-sulfoximine; BSO
Online: 12 May 2023 (14:47:52 CEST)
Ferroptosis is a unique variety of non-apoptotic cell death, driven by massive lipid oxidation in an iron-dependent manner. Since Ferroptosis was introduced as a concept in 2012, it was shown it's essential role in the pathogenesis in neurodegenerative diseases and an important role in therapy-resistant cancer cells. Thus, a detailed molecular understanding of both canonical and alternative ferroptosis pathways are required. There is a set of widely used chemical agents to modulate ferroptosis using different pathway targets: Erastin blocks cystine-glutamate antiporter, system xc-; ML210 directly inactivate GPX4; L-buthionine sulfoximine (BSO) inhibits γ-glutamylcysteine synthetase, an essential enzyme for glutathione synthesis de novo. Most studies were focused on lipidomic profiling of model systems undergoing death in a ferroptotic modality.
REVIEW | doi:10.20944/preprints202205.0314.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: systems genetics 1; mouse 2; Drosophila 3; Saccharomyces cerevisiae; translational research 4; genetic background: precision medicine 5; gene mapping 6.
Online: 24 May 2022 (03:37:31 CEST)
We are all similar, but a bit different. These differences are partially due to variations in our genomes and are related to the heterogeneity of symptoms and responses to treatments that patients exhibit. Most animal studies are performed in one single strain with one manipulation. However, due to the lack of variability, therapies are not always reproducible when treatments are translated to humans. Panels of already sequenced organisms are valuable tools for mimicking human phenotypic heterogeneities and gene mapping. This review summarizes the current knowledge of mouse, fly and yeast panels with insightful applications for translational research.
ARTICLE | doi:10.20944/preprints202306.1153.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: Fanconi anemia (FA); FANCG, interstrand crosslink (ICL); DNA damage response; genetically engineered mouse model (GEMM); CRISPR/Cas9; cisplatin; Mitomycin C (MMC); hematopoiesis
Online: 15 June 2023 (13:29:56 CEST)
Fanconi anemia (FA) develops due to a mutation in one of the FANC genes that are involved in repair of interstrand crosslinks (ICLs). FANCG, a member of the FA core complex, is essential for ICL repair. Previous FANCG-deficient mouse models were generated with drug-based selection cassettes in mixed mice backgrounds, leading to a disparity in interpretation of genotype-related phenotype. To exclude these confounders, we created a Fancg-KO (KO) mouse model using CRISPR/Cas9. The entire Fancg locus was targeted and maintained on the immunological well-characterized C57BL/6J background. Intercrossing of heterozygous mice resulted in sub-Mendelian numbers of homozygous mice, suggesting loss of FANCG can be embryonic lethal. KO mice displayed infertility, hypogonadism but no other developmental problems. Bone marrow analysis revealed a defect in various hematopoietic stem and progenitor subsets with a bias towards myelopoiesis. Cell lines derived from Fancg-KO mice were hypersensitive to crosslinking agents-cisplatin and Mitomycin C, and Fancg-KO mouse embryonic fibroblasts (MEFs) displayed increased γ-H2AX upon cisplatin treatment. Reconstitution of these MEFs with Fancg cDNA corrected for the ICL hypersensitivity. Collectively, this project provides a new, genetically and immunologically well-defined Fancg-KO mouse model for further in vivo and in vitro studies on FANCG and ICL repair.
REVIEW | doi:10.20944/preprints201907.0265.v2
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Aging; Alzheimer’s disease; brain insulin resistance; db/db diabetic mouse model; diabetic cognopathy; insulin resistance; metabolic syndrome; mixed dementia; obesity; type 2 diabetes mellitus
Online: 9 September 2019 (06:12:15 CEST)
Type 2 diabetes mellitus (T2DM) and late-onset Alzheimer’s disease-dementia (LOAD) are increasing in global prevalence and current predictions indicate they will only increase over the coming decades. These increases may be a result of the concurrent increases of obesity and aging. T2DM is associated with cognitive impairments associated with metabolic factors and increases the cellular vulnerability to develop the age-related increased risk of LOAD. This review addresses possible mechanisms due to obesity, aging, multiple intersections between T2DM and LOAD and mechanisms for the continuum of progression. Multiple ultrastructural images in female diabetic db/db models are utilized to demonstrate marked cellular remodeling changes of mural and glia cells and provide for the discussion of functional changes in T2DM. Throughout this review multiple endeavors to demonstrate how T2DM increases the vulnerability of the brain’s neurovascular unit (NVU), neuroglia and neurons are presented. Five major intersecting links are considered: i. aging (chronic age-related diseases); ii. metabolic (hyperglycemia - advanced glycation end-products and its receptor (AGE/RAGE) interactions and hyperinsulinemia – insulin resistance (a linking linchpin); iii. oxidative stress (reactive oxygen-nitrogen species); iv. inflammation (peripheral macrophage and central brain microglia); v. vascular (macrovascular accelerated atherosclerosis - vascular stiffening and microvascular NVU/neuroglial remodeling) with resulting impaired cerebral blood flow.
ARTICLE | doi:10.20944/preprints202306.0537.v1
Subject: Medicine And Pharmacology, Pulmonary And Respiratory Medicine Keywords: resistin like molecule; pulmonary hypertension; type 2 inflammation; adaptive immune response; retnla; retnlb; retnlg; mouse strains; experimental pulmonary hypertension; urban PM; urban fine dust; immune response in pulmonary hypertension
Online: 7 June 2023 (10:40:37 CEST)
Pulmonary hypertension (PH) has a high mortality, and few treatment options. Adaptive immune mediators of PH in mice challenged with antigen/particulate matter (antigen/PM) has been the focus of our prior work. We identified key roles of type 2 and type 17 responses in C57BL/6 mice. Here, we focused on type 2 response related cytokines, specifically Resistin-like-molecule (RELM)α, a critical mediator of hypoxia-induced PH. Because of strain differences in the immune responses to type 2 stimuli, we compared C57BL/6J and BALB/c mice. A model of intraperitoneal antigen sensitization with subsequent, intranasal challenges with antigen/PM (ovalbumin and urban ambient PM2.5) or saline was used in C57BL/6 and BALB/c wild type or RELMα-/- mice. Vascular remodeling was assessed by histology, right ventricular (RV) pressure, RV weights and cytokines were quantified. Upon challenge with antigen/PM2.5, both C57BL/6 and BALB/c mice developed pulmonary vascular remodeling; these changes were more prominent in the C57BL/6 strain. Compared to wild type mice, RELMα-/- had significantly reduced pulmonary vascular remodeling in BALB/c, but not in C57BL/6 mice. RV weights, RV IL-33 and RV ST2-IL-33-receptor were significantly increased in BALB/c wild type mice, but not in BALB/c-RELMα-/- or in C57BL/6-wild type or C57BL/6-RELMα-/- mice. RV systolic pressures (RVSP) were higher in BALB/c compared to C57BL/6J mice, and RELMα-/- were not different from their respective wild type controls. In BALB/c mice, RELMα was a key contributor to antigen/PM2.5 induced pulmonary vascular remodeling, RV thickening and RV cytokine responses, highlighting the significance of the genetic background. The RELMα-/- animals demonstrated significantly decreased expression of RELMβ and RELM which makes these mice comparable to a situation where human RELMα levels would be significantly modified, as humans only have one RELM molecule.
REVIEW | doi:10.20944/preprints201811.0018.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Duchenne muscular dystrophy (DMD); CRISPR/Cas9; exon skipping therapy; gene editing; human induced pluripotent stem cells (hiPSCs); immortalized patient muscle cells; mdx mice; humanized dystrophic mouse models; deltaE50-MD dog model
Online: 2 November 2018 (05:14:23 CET)
Duchenne muscular dystrophy (DMD) is a fatal X-linked recessive neuromuscular disease prevalent in 1 in 3500 to 5000 males worldwide. As a result of mutations that interrupt the reading frame of the dystrophin gene (DMD), DMD is characterized by a loss of dystrophin protein which leads to decreased muscle membrane integrity, which increases susceptibility to degeneration. CRISPR/Cas9 technology has garnered interest as an avenue for DMD therapy due to its potential for permanent exon skipping, which can restore the disrupted DMD reading frame in DMD and lead to dystrophin restoration. An RNA-guided DNA endonuclease system, CRISPR/Cas9 allows for the targeted editing of specific sequences in the genome. The efficacy and safety of CRISPR/Cas9 as a therapy for DMD has been evaluated by numerous studies in vitro and in vivo, with varying rates of success. Despite the potential of CRISPR/Cas9-mediated gene editing for the long-term treatment of DMD, its translation into the clinic is currently challenged by issues such as off-targeting, immune response activation, and sub-optimal in vivo delivery. Its nature as being mostly a personalized form of therapy also limits applicability to DMD patients, who exhibit a wide spectrum of mutations. This review summarizes the various CRISPR/Cas9 strategies that have been tested in vitro and in vivo for the treatment of DMD. Perspectives on the approach will be provided, and the challenges faced by CRISPR/Cas9 in its road to the clinic will be briefly discussed.