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:Triglyceride accumulation in nonalcoholic fatty liver (NAFL) results from unbalanced lipid metabolism which, in the liver, is controlled by several transcription factors. The Foxa subfamily of winged helix/forkhead box (Fox) transcription factors comprises three members which play important roles in controlling both metabolism and homeostasis through the regulation of multiple target genes in the liver, pancreas and adipose tissue. In the mouse liver, Foxa2 is repressed by insulin and mediates fasting responses. Unlike Foxa2, however, the role of Foxa1 in the liver has not yet been investigated in detail. In this study, we evaluate the role of Foxa1 in two human liver cell models, primary cultured hepatocytes and HepG2 cells, by adenoviral infection. Moreover, human and rat livers were analyzed to determine Foxa1 regulation in NAFL. Results demonstrate that Foxa1 is a potent inhibitor of hepatic triglyceride synthesis, accumulation and secretion by repressing the expression of multiple target genes of these pathways (e.g., GPAM, DGAT2, MTP, APOB). Moreover, Foxa1 represses the fatty acid transporter FATP2 and lowers fatty acid uptake. Foxa1 also increases the breakdown of fatty acids by inducing HMGCS2 and ketone body synthesis. Finally, Foxa1 is able to largely up-regulate UCP1, thereby dissipating energy and consistently decreasing the mitochondria membrane potential. We also report that human and rat NAFL have a reduced Foxa1 expression, possibly through a protein kinase C-dependent pathway. We conclude that Foxa1 is an antisteatotic factor that coordinately tunes several lipid metabolism pathways to block triglyceride accumulation in hepatocytes. However, Foxa1 is down-regulated in human and rat NAFL and, therefore, increasing Foxa1 levels could protect from steatosis. Altogether, we suggest that Foxa1 could be a novel therapeutic target for NAFL disease and insulin resistance. To determine the global impact of Foxa1 on human liver gene transcription, microarray expression analyses were performed in HepG2 cells transfected with Ad-Foxa1 or Ad-Control. We used microarrays to detail the global programme of gene expression in HepG2 cells infected with Ad-Foxa1 or control adenovirus (insertless Ad-pACC).
Project description:Triglyceride accumulation in nonalcoholic fatty liver (NAFL) results from unbalanced lipid metabolism which, in the liver, is controlled by several transcription factors. The Foxa subfamily of winged helix/forkhead box (Fox) transcription factors comprises three members which play important roles in controlling both metabolism and homeostasis through the regulation of multiple target genes in the liver, pancreas and adipose tissue. In the mouse liver, Foxa2 is repressed by insulin and mediates fasting responses. Unlike Foxa2, however, the role of Foxa1 in the liver has not yet been investigated in detail. In this study, we evaluate the role of Foxa1 in two human liver cell models, primary cultured hepatocytes and HepG2 cells, by adenoviral infection. Moreover, human and rat livers were analyzed to determine Foxa1 regulation in NAFL. Results demonstrate that Foxa1 is a potent inhibitor of hepatic triglyceride synthesis, accumulation and secretion by repressing the expression of multiple target genes of these pathways (e.g., GPAM, DGAT2, MTP, APOB). Moreover, Foxa1 represses the fatty acid transporter FATP2 and lowers fatty acid uptake. Foxa1 also increases the breakdown of fatty acids by inducing HMGCS2 and ketone body synthesis. Finally, Foxa1 is able to largely up-regulate UCP1, thereby dissipating energy and consistently decreasing the mitochondria membrane potential. We also report that human and rat NAFL have a reduced Foxa1 expression, possibly through a protein kinase C-dependent pathway. We conclude that Foxa1 is an antisteatotic factor that coordinately tunes several lipid metabolism pathways to block triglyceride accumulation in hepatocytes. However, Foxa1 is down-regulated in human and rat NAFL and, therefore, increasing Foxa1 levels could protect from steatosis. Altogether, we suggest that Foxa1 could be a novel therapeutic target for NAFL disease and insulin resistance. To determine the global impact of Foxa1 on human liver gene transcription, microarray expression analyses were performed in human hepatocytes transfected with Ad-Foxa1 or Ad-Control. We used microarrays to detail the global programme of gene expression in human hepatocytes infected with Ad-Foxa1 or control adenovirus (insertless Ad-pACC).
Project description:Triglyceride accumulation in nonalcoholic fatty liver (NAFL) results from unbalanced lipid metabolism which, in the liver, is controlled by several transcription factors. The Foxa subfamily of winged helix/forkhead box (Fox) transcription factors comprises three members which play important roles in controlling both metabolism and homeostasis through the regulation of multiple target genes in the liver, pancreas and adipose tissue. In the mouse liver, Foxa2 is repressed by insulin and mediates fasting responses. Unlike Foxa2, however, the role of Foxa1 in the liver has not yet been investigated in detail. In this study, we evaluate the role of Foxa1 in two human liver cell models, primary cultured hepatocytes and HepG2 cells, by adenoviral infection. Moreover, human and rat livers were analyzed to determine Foxa1 regulation in NAFL. Results demonstrate that Foxa1 is a potent inhibitor of hepatic triglyceride synthesis, accumulation and secretion by repressing the expression of multiple target genes of these pathways (e.g., GPAM, DGAT2, MTP, APOB). Moreover, Foxa1 represses the fatty acid transporter FATP2 and lowers fatty acid uptake. Foxa1 also increases the breakdown of fatty acids by inducing HMGCS2 and ketone body synthesis. Finally, Foxa1 is able to largely up-regulate UCP1, thereby dissipating energy and consistently decreasing the mitochondria membrane potential. We also report that human and rat NAFL have a reduced Foxa1 expression, possibly through a protein kinase C-dependent pathway. We conclude that Foxa1 is an antisteatotic factor that coordinately tunes several lipid metabolism pathways to block triglyceride accumulation in hepatocytes. However, Foxa1 is down-regulated in human and rat NAFL and, therefore, increasing Foxa1 levels could protect from steatosis. Altogether, we suggest that Foxa1 could be a novel therapeutic target for NAFL disease and insulin resistance. To determine the global impact of Foxa1 on human liver gene transcription, microarray expression analyses were performed in HepG2 cells transfected with Ad-Foxa1 or Ad-Control.
Project description:Triglyceride accumulation in nonalcoholic fatty liver (NAFL) results from unbalanced lipid metabolism which, in the liver, is controlled by several transcription factors. The Foxa subfamily of winged helix/forkhead box (Fox) transcription factors comprises three members which play important roles in controlling both metabolism and homeostasis through the regulation of multiple target genes in the liver, pancreas and adipose tissue. In the mouse liver, Foxa2 is repressed by insulin and mediates fasting responses. Unlike Foxa2, however, the role of Foxa1 in the liver has not yet been investigated in detail. In this study, we evaluate the role of Foxa1 in two human liver cell models, primary cultured hepatocytes and HepG2 cells, by adenoviral infection. Moreover, human and rat livers were analyzed to determine Foxa1 regulation in NAFL. Results demonstrate that Foxa1 is a potent inhibitor of hepatic triglyceride synthesis, accumulation and secretion by repressing the expression of multiple target genes of these pathways (e.g., GPAM, DGAT2, MTP, APOB). Moreover, Foxa1 represses the fatty acid transporter FATP2 and lowers fatty acid uptake. Foxa1 also increases the breakdown of fatty acids by inducing HMGCS2 and ketone body synthesis. Finally, Foxa1 is able to largely up-regulate UCP1, thereby dissipating energy and consistently decreasing the mitochondria membrane potential. We also report that human and rat NAFL have a reduced Foxa1 expression, possibly through a protein kinase C-dependent pathway. We conclude that Foxa1 is an antisteatotic factor that coordinately tunes several lipid metabolism pathways to block triglyceride accumulation in hepatocytes. However, Foxa1 is down-regulated in human and rat NAFL and, therefore, increasing Foxa1 levels could protect from steatosis. Altogether, we suggest that Foxa1 could be a novel therapeutic target for NAFL disease and insulin resistance. To determine the global impact of Foxa1 on human liver gene transcription, microarray expression analyses were performed in human hepatocytes transfected with Ad-Foxa1 or Ad-Control.
Project description:Sesamin, a special compound present in sesame and sesame oil, has been reported the role in regulating blood lipids and improving liver function, while the underlying mechanisms remain unclear. This study aims to explore its potential mechanisms in regulating lipid metabolism. HepG2 cells were treated with oleic acid to establish an in vitro high-fat cell model to simulate impaired hepatocytes under lipid metabolism disorders.Differentially expressed genes during the sesame intervention were screened by RNA sequencing (RNA seq) and validated using real-time quantitative PCR and Western blot.The data showed that sesamin significantly upregulated the mRNA levels of genes involved in fatty acid metabolism processes such as ETFB, ACAT2, FADS2, FABP1, ACOT1, and those involved in cholesterol metabolism processes such as FDPS, PCSK9, and DHCR7, and downregulated the mRNA levels of CYP24A1 and GGT5 involved in fatty acid metabolism, as well as MVK involved in cholesterol synthesis. Sesamin significantly down-regulated the protein levels of NOTCH1, CD36, SOX4, and FABP1. In summary, sesamin alleviates lipid accumulation in HepG2 by regulating lipid metabolism, with potential mechanisms involving steroid biosynthesis, unsaturated fatty acid biosynthesis, fat digestion and absorption, fatty acid metabolism, Notch signaling pathway, and PPAR signaling pathway.
Project description:Nonalcoholic fatty liver disease (NAFLD) is one of the main causes of liver diseases in the world. At present, the pathogenesis of NAFLD is not completely clear, and the regulatory role of inflammatory corpuscles in NAFLD-related metabolic diseases is increasingly prominent. NLRP6 is a member of the NLRs family of pattern recognition receptors and is related to the occurrence and development of NAFLD, but the specific mechanism is still unclear. We report here that NLRP6 is an important regulator of liver lipid metabolism, and its absence will affect the formation and accumulation of lipid droplets in the liver. In the HFD-induced NAFLD model group, NLRP6 deletion increased the mouse lipid content and aggravated hepatocyte steatosis by up-regulating the expressions of ADRP and CIDEC and down-regulating the expression of ApoB100.On the contrary, overexpression of NLRP6 in hepatocytes can significantly reduce intracellular lipid content and lipid droplets, and reduce the expression of ADRP and CIDEC. Indicated that NLRP6 can inhibit the accumulation of lipid droplets in hepatocytes by regulating the expression of ADRP, CIDEC and ApoB100, and thus alleviating the symptoms of NAFLD.
Project description:Dual specificity phosphatase 6 (DUSP6) is a specific phosphatase for mitogen-activated protein kinase (MAPK). In this study, we used a high-fat diet (HFD)-induced murine non-alcoholic fatty liver disease (NAFLD) model to investigate the role of DUSP6 in this disease. Wild-type (WT) and Dusp6-haploinsufficient (HI) mice developed severe obesity and liver pathology consistent with NAFLD when exposed to HFD. In contrast, Dusp6-knockout (KO) mice completely eliminated these phenotypes. Furthermore, primary hepatocytes isolated from WT mice exposed to palmitic and oleic acids exhibited abundant intracellular lipid accumulation, while hepatocytes from Dusp6-KO mice showed minimal lipid accumulation. Transcriptome analysis revealed significant downregulation of genes encoding cytochrome P450 4A (CYP4A), known to promote ω-hydroxylation of fatty acids and hepatic steatosis, in Dusp6-KO hepatocytes compared with WT hepatocytes. Diminished CYP4A expression was observed in the liver of Dusp6-KO mice compared to WT and Dusp6-HI mice. Knockdown of DUSP6 in HepG2, a human liver-lineage cell line, also promoted a reduction of lipid accumulation, downregulation of CYP4A, and upregulation of phosphorylated/activated MAPK. Furthermore, inhibition of MAPK activity promoted lipid accumulation in DUSP6-knockdown HepG2 cells without affecting CYP4A expression, indicating that CYP4A expression is independent of MAPK activation. These findings highlight the significant role of DUSP6 in HFD-induced steatohepatitis through two distinct pathways involving CYP4A and MAPK.