Project description:The discovery of an emerging viral disease, severe fever with thrombocytopenia syndrome (SFTS), caused by SFTS virus (SFTSV), has prompted the need to understand pathogenesis of SFTSV. We are unique in establishing an infectious model of SFTS in C57/BL6 mice, resulting in hallmark symptoms of thrombocytopenia and leukocytopenia. Viral RNA and histopathological changes were identified in the spleen, liver, and kidney. However, viral replication was only found in the spleen, which suggested the spleen to be the principle target organ of SFTSV. Moreover, the number of macrophages and platelets were largely increased in the spleen, and SFTSV colocalized with platelets in cytoplasm of macrophages in the red pulp of the spleen. In vitro cellular assays further revealed that SFTSV adhered to mouse platelets and facilitated the phagocytosis of platelets by mouse primary macrophages, which in combination with in vivo findings, suggests that SFTSV-induced thrombocytopenia is caused by clearance of circulating virus-bound platelets by splenic macrophages. Thus, this study has elucidated the pathogenic mechanisms of thrombocytopenia in a mouse model resembling human SFTS disease.
Project description:We aimed to identify the hepatoprotective effects of Terminalia chebula water extract (TCW) and its corresponding pharmacological actions using C57/BL6 mice model of tert-butylhydroperoxide-(t-BHP-) induced acute liver injury. Mice were orally administered with TCW (0, 50, 100, or 200?mg/kg) or gallic acid (100?mg/kg) for 5 days before t-BHP (2.5?mM/kg) injection. Liver enzymes, histopathology, oxidative stress parameters, antioxidant components, and inflammatory cytokines were examined 18?h after t-BHP injection. t-BHP injection caused dramatic elevation of serum AST, ALT, and LDH level, while TCW pretreatment notably attenuated these elevations. Inflammatory cytokines including TNF-?, IL-1?, and IL-6 were notably increased in hepatic tissues, and then these were efficiently attenuated by TCW pretreatment. t-BHP injection notably increased malondialdehyde, total reactive oxygen species, and nitric oxide in the liver tissue, while it markedly dropped the antioxidant activities including total antioxidant capacity, total glutathione contents, glutathione peroxidase, superoxide dismutase, and catalase. TCW pretreatment remarkably ameliorated these alterations, and these effects were relevant to gene expressions. Histopathological examinations supported the above findings. Collectively, these findings well prove that TCW beneficially prevents acute and severe liver injury and clarify its corresponding mechanisms involved in the inhibition of oxidative stress and inflammatory cytokines.
Project description:BackgroundSevere fever with thrombocytopenia syndrome virus (SFTSV) is a novel tick-borne phlebovirus, which is listed in the most dangerous pathogens by the World Health Organization, and has 12-30% fatality rates. SFTSV antibodies were reported in minks that experienced abortion or reproductive failure. The aim of this study was to determine whether SFTSV infection causes an adverse pregnancy outcome in the fetus using a pregnant mouse model.Methodology/principal findingsWe found SFTSV in the fetus after infection in pregnant mice, and some dams showed adverse pregnancy outcomes after infection with SFTSV including placental damage, fetal reabsorption, and fetal intrauterine growth restriction (IUGR). SFTSV had obvious tropism characteristics in the placenta, especially in the labyrinth. In early-gestation, pregnant mice infected with SFTSV had fetal IUGR and a high viral load in the fetus. The virus widely spread in infected fetuses, including the hindbrain, thymus, heart, spinal cord, and liver.ConclusionsOur study demonstrated that SFTSV was vertically transmitted to the fetus through the placental barrier of immunocompetent mice, and resulted in adverse pregnancy outcomes.
Project description:Here, the complete genome sequence of Duncaniella muris strain B8 is presented. The anaerobic strain was isolated from the feces of C57/BL6 mice and is closely related to D. muris strain DSM 103720, which is the type strain of the recently proposed genus Duncaniella of the Muribaculaceae.
Project description:The C57/BL6 (B6) mouse strain exhibits post-hypoxic frequency decline and periodic breathing, as well as greater amount of irregular breathing during rest in comparison to the A/J and to the B6a1, a chromosomal substitution strain whereby the A/J chromosome 1 is bred onto the B6 background (Han et al., 2002; Yamauchi et al., 2008a,b). The hypothesis was that morphological differences in the carotid body would associate with such trait variations. After confirming strain differences in post-hypoxic ventilatory behavior, histological examination (n=8 in each group) using hematoxylin and eosin (H&E) staining revealed equivalent, well-defined tissue structure at the bifurcation of the carotid arteries, an active secretory parenchyma (type I cells) from the supportive stromal tissue, and clustering of type I cells in all three strains. Tyrosine hydroxylase (TH) immunohistochemical staining revealed a typical organization of type I cells and neurovascular components into glomeruli in all three strains. Image analysis from 5 ?m sections from each strain generated a series of cytological metrics. The percent carotid body composition of TH+ type I cells in the A/J, B6 and B6a1 was 20±4%, 39±3%, and 44±3%, respectively (p=0.00004). However, cellular organization in terms of density and ultrastructure in the B6a1 is more similar to the B6 than to the A/J. These findings indicate that genetic mechanisms that produce strain differences in ventilatory function do not associate with carotid body structure or tyrosine hydroxylase morphology, and that A/J chromosome 1 does not contribute much to B6 carotid body morphology.
Project description:Various disturbances of social behavior, such as autism, depression, or posttraumatic stress disorder, have been associated with an altered steroid hormone homeostasis and a dysregulation of the hypothalamus-pituitary-adrenal axis. A link between steroid hormone antagonists and the treatment of stress-related conditions has been suggested. We evaluated the effects of stress induction on social behavior in the three chambers and its potential reversibility upon specific steroid hormone antagonism in mice. C57BL/6 mice were stressed twice daily for 8 days by chronic swim testing. Social behavior was evaluated by measuring, first, the preference for sociability and, second, the preference for social novelty in the three-chamber approach before and after the chronic swim test. The reversibility of behavior upon stress induction was analyzed after applying steroid hormone antagonists targeting glucocorticoids with etomidate, mineralocorticoids with potassium canrenoate, and androgens with cyproterone acetate and metformin. In the chronic swim test, increased floating time from 0.8?±?0.2 min up to 4.8?±?0.25 min was detected (p?<?0.01). In the three-chamber approach, increased preference for sociability and decreased preference for social novelty was detected pre- versus post-stress induction. These alterations of social behavior were barely affected by etomidate and potassium canrenoate, whereas the two androgen antagonists metformin and cyproterone acetate restored social behavior even beyond baseline conditions. The alteration of social behavior was better reversed by the androgen as compared with the glucocorticoid and mineralocorticoid antagonists. This suggests that social behavior is primarily controlled by androgen rather than by glucocorticoid or mineralocorticoid action. The stress-induced changes in preference for sociability are incompletely explained by steroid hormone action alone. As the best response was related to metformin, an effect via glucose levels might confound the results and should be subject to future research.
Project description:PurposeCurrently approved therapies for multiple sclerosis (MS) at best only slow down its progression. Therefore, it is necessary to utilize novel technologies in order to synthesize smart multifunctional structures. In the present study, for the first time we evaluated the therapeutic potential of MSc1 nanocomplex, which was designed based on novel nanochelating technology.Materials and methodsMSc1 cell-protection capacity, with and without iron bond, was evaluated against hydrogen peroxide (H2O2)-induced oxidative stress in cultured rat pheochromocytoma-12 cells. The ability of MSc1 to maintain iron bond at pH ranges of 1-7 was evaluated. Nanocomplex toxicity was examined by estimating the intraperitoneal median lethal dose (LD50). Experimental autoimmune encephalomyelitic mice were injected with MSc1 14 days after disease induction, when the clinical symptoms appeared. The clinical score, body weight, and disease-induced mortality were monitored until day 54. In the end, after collecting blood samples for assessing hemoglobin and red blood cell count, the brains and livers of the mice were isolated for hematoxylin and eosin staining and analysis of iron content, respectively.ResultsThe results showed that MSc1 prevented H2O2-induced cell death even after binding with iron, and it preserved its bond with iron constant at pH ranges 1-7. The nanocomplex intraperitoneal LD50 was 1,776.59 mg/kg. MSc1 prompted therapeutic behavior and improved the disabling features of experimental autoimmune encephalomyelitis, which was confirmed by decreased clinical scores versus increased body mass and 100% survival probability. It did not cause any adverse effects on hemoglobin or red blood cell count. Histopathological studies showed no neural loss or lymphocyte infiltration in MSc1-treated mice, while the hepatic iron content was also normal.ConclusionThese results demonstrate that MSc1 could be a promising beneficial novel agent and has the capacity to be evaluated in further studies.
Project description:The RNA-binding protein Rbm24 has recently been identified as a pivotal splicing factor in the developing heart. Loss of Rbm24 in mice disrupts cardiac development by governing a large number of muscle- specific splicing events. Since Rbm24 knockout mice are embryonically lethal, the role of Rbm24 in the adult heart remained unexplored. Here, we used adeno-associated viruses (AAV9) to investigate the effect of increased Rbm24 levels in adult mouse heart. Using high-resolution microarrays, we found 893 differentially expressed genes and 1102 differential splicing events in 714 genes in hearts overexpressing Rbm24. We found splicing differences in cardiac genes, such as PDZ and Lim domain 5, Phospholamban, and Titin, but did not find splicing differences in previously identified embryonic splicing targets of Rbm24, such as skNAC, αNAC, and Coro6. Gene ontology enrichment analysis demonstrated increased expression of extracellular matrix (ECM)-related and immune response genes. Moreover, we found increased expression of Tgfβ-signaling genes, suggesting enhanced Tgfβ-signaling in these hearts. Ultimately, this increased activation of cardiac fibroblasts, as evidenced by robust expression of Periostin in the heart, and extensive cardiac fibrosis. These results indicate that Rbm24 may function as a regulator of cardiac fibrosis, potentially through the regulation of TgfβR1 and TgfβR2 expression.
Project description:BackgroundThe individual genetic variations, as a response to diet, have recently caught the attention of several researchers. In addition, there is also a trend to assume food containing beneficial substances, or to supplement food with specific compounds. Among these, there is the conjugated linoleic acid (CLA), which has been demonstrated to reduce fat mass and to increase lean mass, even though its mechanism of action is still not known. We investigated the effect of CLA isomers (CLA c9,t11 and CLA t10,c12) on the proteomic profile of liver, adipose tissue, and muscle of mouse, with the aim of verifying the presence of a modification in fat and lean mass, and to explore the mechanism of action.MethodsC57/BL6 mice were fed for 2 months with different diets: (1) standard chow, (2) CLA c9,t11 diet, (3) CLA t10,c11 diet, (4) CLA isomers mixture diet, and (5) linoleic acid diet. The proteomic profile of liver, white adipose tissue, and muscle was investigated. Statistical significance of the spots with an intensity higher than twofold in expression compared to the control was tested using student's t test (two-tail).ResultsWe found that both isomers modulate the proteomic profiles of liver, adipose tissue, and muscle by different mechanisms of action. Liver steatosis is mostly due to the isomer CLA t10,c12, since it alters the expression of lipogenetic proteins; it acts also reducing the adipose tissue and increasing fatty acid oxidation in muscle. Conversely, CLA c9,t11 has no relevant effects on liver and adipose tissue, but acts mostly on muscle, where it enhances muscular cell differentiation.ConclusionsAdministration of CLA in humans has to be carefully personalized, since even considering the presence of a species-specific effect, adverse effects might occur on long-term supplementation. Here we demonstrated that, in mouse, CLA is effective in reducing fat mass, but it also induces liver steatosis. The increase of lean mass is linked to an induction of cell proliferation, which, on long-term supplementation, might also lead to adverse effects.