Project description:To investigate the function of miRNAs in liver, we obtained liver tissues from nonsteatotic individuals and fatty livers from patients with nonalcoholic fatty liver disease (NAFLD). Patients due to excessive alcohol consumption, autoimmune liver disease, viral hepatitis and diabetes were excluded. Nonsteatotic livers were collected from the normal region of the livers from donors who received liver resection due to liver hemangioma, and were defined as those with NASH activity scores of 0 We then performed miRNA sequencing using livers from two NAFLD patients and two nonsteatotic individuals.
Project description:This SuperSeries is composed of the following subset Series: GSE30447: Foxa1 Reduces Lipid Accumulation in Human Hepatocytes and Is Down-regulated in Nonalcoholic Fatty Liver (HepG2 data) GSE30450: Foxa1 Reduces Lipid Accumulation in Human Hepatocytes and Is Down-regulated in Nonalcoholic Fatty Liver (hepatocytes data) Refer to individual Series
Project description:The current study was designed to determine if dietary fatty acid concentration and composition affects the development and progression of nonalcoholic fatty liver disease. Male SD rats were overfed diets low (5%) or high (70%) fat diets via total enteral nutrition where the fat source was olive oil (monounsaturated), or corn oil (polyunsaturated). Overfeeding 5% corn oil produced little steatosis relative to feeding 5% olive oil. This was associated with lower fatty acid synthesis and reduced SREBP-c signaling in the 5% corn oil group. Overfeeding 70% fat diets increased steatosis and lead to increased liver necrosis in the 70% corn oil but not olive oil group. Increased injury after feeding polyunsaturated fat diets was linked to peroxidizability of hepatic free fatty acids and triglycerides and appearance of peroxidaized lipid products HETES and HODES previously linked to clinical nonalcoholic steatohepatitis. Male SD rats were overfed diets low (5%) or high (70%) fat diets via total enteral nutrition where the fat source was olive oil (monounsaturated) or corn oil (polyunsaturated).
Project description:Background & aims: The role of microRNAs (miRNAs) in Alcoholic Hepatitis (AH) and their potential as therapeutic targets in liver disease has not been explored yet. This study aims at profiling miRNA in AH and identifying dysregulated miRNAs involved in AH pathophysiology. Methods: miRNA expression arrays were performed in 13 AH, 5 alcohol liver disease-induced cirrhosis (ALD-CH), 5 nonalcoholic steatohepatitis induced cirrhosis (NASH-CH), 4 HCV-induced cirrhosis (HCV-CH) and 6 non-injured liver control samples. Genome wide expression profile was retrieved for 12 paired AH and control samples. MiRNA and mRNA expression data was integrated and identified miRNAs were validated in AH samples and in animal models of liver injury. Results: The miRNA array showed 111 upregulated and 66 downregulated miRNAs in AH versus healthy subjects. The comparison of miRNA profile in liver samples from AH among ALD-CH, HCV-CH and NASH-CH identified 18 miRNAs specifically dysregulated in AH. Integrative miRNA and mRNA analysis in AH identified dysregulated miRNAs for which their target genes were also dysregulated. A functional analysis of identified miRNAs and their targets revealed their involvement in the regulation of canonical pathways related to apoptosis, fatty acid metabolism and cell cycle among others. miRNAs expression (miR-182, miR-21, miR-155, miR-214, miR-432, miR-422a) was validated in an independent cohort of AH. MiR-182 expression correlated with cholestasis, disease severity and short-term mortality. Moreover, miR-182 expression is associated to cholestasis with ductular reaction but not to fibrosis and inflammation in animal models of liver injury. Conclusions: AH is characterized by an important dysregulation of miRNA expression with a unique miRNA profile. MiRNAs specifically expressed in AH are associated to cholestasis⦠Uncovered miRNAs are involved in important pathophysiological features in AH suggesting ta regulation of he role of miRNAs in the regulation of AH, and highlight miR-182 as a potential regulator of its pathophysiology. miRNA expression arrays were performed in 13 AH(Alcoholic hepatitis), 5 alcohol liver disease-induced cirrhosis (ALD-CH), 5 nonalcoholic steatohepatitis induced cirrhosis (NASH-CH), 4 HCV-induced cirrhosis (HCV-CH) and 6 non-injured liver control samples(CTRL).
Project description:Nonalcoholic steatohepatitis (NASH), a severe form of nonalcoholic fatty liver disease, is characterized by hepatic steatosis and hepatocellular injury and progresses to cirrhosis and hepatocellular carcinoma. Sterol regulatory element-binding proteins (SREBPs) are master regulators of lipogenesis. Liver-specific PTEN knockout (KO) mice show constitutive upregulation of SREBP through PI3K-Akt pathway activation, leading to spontaneous fatty liver and subsequent HCC development. SREBP cleavage-activating protein (SCAP) plays a critical role in SREBP activation. We sought to determine the impact of SREBP inhibition on NASH and HCC development. To this end, we additionally inhibited SREBP pathway in liver-specific PTEN mice by ablating SCAP and generated liver-specific PTEN/SCAP double KO (DKO) mice. However unexpectedly, inhibition of SCAP/SREBP pathway markedly exacerbated liver injury (5weeks), fibrosis (5months), and carcinogenesis (7 months) in PTEN KO mice. To elucidate the mechanisms of liver injury in liver-specific PTEN/SCAP DKO mice, we conducted transcriptome analyses of the livers.
Project description:Response of Epithelial cells to the injury caused by different Klebsiella strains at different time points. K. pneumoniae strains used are: Wild type, Descapsulated mutant and LPS O-Chain mutant. Time points considered are: 4 hr, 6 hr and 10 hr
