Project description:In this experiment, we studied how human beta defensin-2 (hBD-2) affects gene expression of T cells. Murine splenic C57BL/6 CD4/CD8 T cells were stimulated with anti-CD3/anti-CD28 beads and hBD-2 or vehicle (PBS) control for 48h before RNA isolation
Project description:Alcohol-associated liver disease (ALD) is a major cause of alcohol related mortality. The specific mechanisms responsible for ALD development and progression are not fully understood, and there is limited therapy for any stage of ALD. Sex differences are often disregarded in in genetic and mechanistic studies. We aimed to take an unbiased approach to define sex specific pathways in livers exposed to alcohol. METHODS: Mice were fed LieberDeCarli alcohol liquid diet for 3 weeks. To identify the role of Kdm5b and Kdm5c we injected mice with AAV-shControl at 2x10^11 gc per mouse or AAV-shKdm5b and AAV-Kdm5c vectors at 10^11 gc per mouse. To assess the role of AhR we injected mice with AAV-shControl or AAV-shAhR vectors at 10^11 gc per mouse. RESULTS: We found several pathways affected by alcohol in sex specific way and identified KDM5 demethylases as contributors to that specificity.
Project description:Mitochondrial MATα1 is selectively depleted in alcohol-associated liver disease through a mechanism that involves the isomerase PIN1 and the kinase CK2. Alcohol activates CK2, which phosphorylates MATα1 at Ser114 facilitating interaction with PIN1, thereby inhibiting its mitochondrial localization. Blocking PIN1-MATα1 interaction increased mitochondrial MATα1 levels and protected against alcohol-induced mitochondrial dysfunction.
Project description:Alcohol-associated liver disease (ALD) is a major cause of alcohol related mortality. Recently we identified hepatic demethylases KDM5B and KDM5C as important sex-specific epigenetic regulators of alcohol response in the liver. In this study we aimed to study the molecular mechanisms of KDM5-dependent ALD development and resolution. We found that alcohol induces pathological changes in cell-cell communication in the liver that are in part mediated by epigenetic changes in hepatocytes mediated by histone demethylase KDM5B. Using cell type specific knockout mice, we found that KDM5B histone demethylase was a key regulator of alcohol-induced epigenetic changes in hepatocytes. Moreover, it regulated hepatocytes-non-parenchymal cell crosstalk that promoted inflammation and fibrosis development in ALD. This mechanism was specific to females. In males KDM5B deficiency was not sufficient to prevent fibrosis development. In contrast KDM5B demethylase loss promoted fibrosis resolution in both males and females. This mechanism involved changes in hepatocyte-macrophage crosstalk and LXRα activation, which we identified to be critical for the fibrosis resolution process. CONCLUSION: In summary, KDM5B demethylase is a regulator of cell-cell crosstalk involved in disease progression in females and in disease resolution in both sexes.
Project description:To investigate the the liver transcriptome at peak injury and during early and late resolution from alcohol-induced liver injury in mice
Project description:Ca2+ overload-induced mitochondrial dysfunction is considered as a major contributing factor in the pathogenesis of alcohol-associated liver disease (ALD). However, the initiating factors that drive mitochondrial Ca2+ accumulation in ALD remain elusive. Here, we demonstrate that an aberrant increase in mitochondria-associated ER membranes (MAMs) mediates Ca2+ accumulation-induced mitochondrial dysfunction in ALD via the formation of glucose-regulated protein 75 (GRP75)-mediated MAM Ca2+-channeling (MCC) complex. Unbiased transcriptomic analysis reveals pyruvate dehydrogenase kinase 4 (PDK4) as a prominently inducible MAM kinase in ALD. Additional mass spectrometry analysis unveils the critical role of PDK4 in promoting alcohol-induced MCC complex formation and mitochondrial dysfunction by phosphorylating GRP75. Non-phosphorylatable GRP75 mutation or genetic ablation of PDK4 prevents alcohol-induced mitochondrial Ca2+ accumulation and dysfunction. Conversely, ectopic induction of MAM formation in PDK4-deficient mice abrogate the protective effect in alcohol-induced liver injury. Together, our study defines the mediatory role of PDK4 in promoting mitochondrial dysfunction in ALD.
Project description:Alcohol-associated liver disease is accompanied by changes in the intestinal mycobiome. How fungal dysbiosis contributes to liver disease is not clear. T-helper (Th17) cells mediate immune responses against fungi, but the interleukin 17 (IL17) pathway has been associated with pathogenesis of alcohol-associated liver disease. Here, we demonstrate that Candida albicans (C. albicans)-specific Th17 cells are increased in the circulation and present in the liver of patients with alcohol-associated liver disease. Chronic ethanol administration to mice results in migration of C. albicans-reactive Th17 cells from the intestine to the liver. The antifungal agent nystatin reduced intestinal fungal overgrowth, decreased C. albicans-specific Th17 cells in the liver, and reduced features of ethanol-induced liver disease in mice. Transgenic mice that express a T-cell receptor (TCR) reactive to Candida antigens develop more severe ethanol-induced liver disease than transgene-negative littermates; disease severity was reduced by administration of an antibody against IL17 to the TCR transgenic mice. Adoptive transfer of C. albicans-reactive Th17 cells exacerbated ethanol-induced liver disease in wild-type mice. IL17 receptor A (IL17ra) signaling in Kupffer cells was required for the effects of C. albicans-reactive Th17 cells. Our findings indicate that ethanol increases C. albicans-reactive Th17 cells, which contribute to alcohol-associated liver disease.
Project description:Alcohol-associated liver disease is accompanied by changes in the intestinal mycobiome. How fungal dysbiosis contributes to liver disease is not clear. T-helper (Th17) cells mediate immune responses against fungi, but the interleukin 17 (IL17) pathway has been associated with pathogenesis of alcohol-associated liver disease. Here, we demonstrate that Candida albicans (C. albicans)-specific Th17 cells are increased in the circulation and present in the liver of patients with alcohol-associated liver disease. Chronic ethanol administration to mice results in migration of C. albicans-reactive Th17 cells from the intestine to the liver. The antifungal agent nystatin reduced intestinal fungal overgrowth, decreased C. albicans-specific Th17 cells in the liver, and reduced features of ethanol-induced liver disease in mice. Transgenic mice that express a T-cell receptor (TCR) reactive to Candida antigens develop more severe ethanol-induced liver disease than transgene-negative littermates; disease severity was reduced by administration of an antibody against IL17 to the TCR transgenic mice. Adoptive transfer of C. albicans-reactive Th17 cells exacerbated ethanol-induced liver disease in wild-type mice. IL17 receptor A (IL17ra) signaling in Kupffer cells was required for the effects of C. albicans-reactive Th17 cells. Our findings indicate that ethanol increases C. albicans-reactive Th17 cells, which contribute to alcohol-associated liver disease.