Project description:*Objectives:* In addition to their well-known role in the control of cellular proliferation and cancer, cell cycle regulators are increasingly identified as important metabolic modulators. Genome wide association studies identified SNPs near the cell cycle regulator CDKN2A/p16INK4a (p16) as strongly associated with risk of developing type 2 diabetes (T2D). T2D is associated with numerous perturbations of hepatic lipid and glucose metabolism. We have recently shown that p16 controls fasting-induced hepatic gluconeogenesis in mice. However, whether p16 may also affect hepatic lipid homeostasis is unknown. *Results:* In primary hepatocytes, p16-deficiency was associated with elevated expression of genes involved in fatty acid catabolism and enhanced activation of PPAR. This led to increased mitochondrial fatty acid oxidation (FAO) through a mechanism requiring the catalytic AMPK 2 subunit and SIRT1. By contrast, *p16* overexpression was associated with triglyceride accumulation and increased lipid droplet numbers *in vitro*, and decreased ketogenesis and hepatic mitochondrial activity *in vivo*. Gene expression analysis of human liver samples revealed a negative correlation between *CDKN2A* expression and *PPARA* and its target genes, suggesting a potential association between hepatic p16 expression and FAO in obese humans. *Conclusions:* Our findings demonstrate that p16 plays a key role in hepatic lipid metabolism and may thus contribute to the development of metabolic diseases.
Project description:The effect of prototypical pregnane receptor X (PXR) agonist (pregnenolone 16α-carbonitrile) PCN on hepatic gene expression was studied in mice primary hepatocytes.
Project description:The effect of PGC-1α overexpression using adenovirus (PGC-1α-Ad) on hepatic gene expression was studied in mice primary hepatocytes.
Project description:This study provides an evaluation of changes in gene expression associated with phenobarbital treatment of rat hepatocytes in vitro. Primary rat hepatocytes were treated for 24 and 48 hours with two doses (300 uM and 3 mM) of phenobarbital and water vehicle control. Five replicates of each treatment were performed. Cells were then extracted and RNA processed for microarray analysis. This series is part of a SuperSeries in which primary rat hepatocytes were treated with two doses of ten chemical compounds (and corresponding vehicle controls) for 24 and 48 hours. Each compound/vehicle treatment group was an individual study performed at different times. Each study was analyzed separately and themes common between studies were reported. Time Course/Dose Response
Project description:This study provides an evaluation of changes in gene expression associated with acetominophen treatment of rat hepatocytes in vitro. Primary rat hepatocytes were treated for 24 and 48 hours with two doses (500 uM and 5 mM) of acetominophen and 1% DMSO vehicle control. Five replicates of each treatment were performed. Cells were then extracted and RNA processed for microarray analysis. This series is part of a SuperSeries in which primary rat hepatocytes were treated with two doses of ten chemical compounds (and corresponding vehicle controls) for 24 and 48 hours. Each compound/vehicle treatment group was an individual study performed at different times. Each study was analyzed separately and themes common between studies were reported. Time Course/Dose Response
Project description:This study provides an evaluation of changes in gene expression associated with clofibrate treatment of rat hepatocytes in vitro. Primary rat hepatocytes were treated for 24 and 48 hours with two doses (60 uM and 1 mM) of clobibrate and 1% DMSO vehicle control. Five replicates of each treatment were performed. Cells were then extracted and RNA processed for microarray analysis. This series is part of a SuperSeries in which primary rat hepatocytes were treated with two doses of ten chemical compounds (and corresponding vehicle controls) for 24 and 48 hours. Each compound/vehicle treatment group was an individual study performed at different times. Each study was analyzed separately and themes common between studies were reported. Time Course/Dose Response
Project description:This study provides an evaluation of changes in gene expression associated with methapyrilene treatment of rat hepatocytes in vitro. Primary rat hepatocytes were treated for 24 and 48 hours with two doses (3 uM and 100 uM) of methaphyriline and 1% DMSO vehicle control. Five replicates of each treatment were performed. Cells were then extracted and RNA processed for microarray analysis. This series is part of a SuperSeries in which primary rat hepatocytes were treated with two doses of ten chemical compounds (and corresponding vehicle controls) for 24 and 48 hours. Each compound/vehicle treatment group was an individual study performed at different times. Each study was analyzed separately and themes common between studies were reported. Time Course/Dose Response
Project description:To investigate the effect of TRIB3 overexpression on regulation of lipid metabolism in hepatocytes, we isolated mouse primary hepatocytes from AAV-GFP or AAV-Trib3 mice. We then performed gene expression profiling analysis using data obtained from RNA-seq of two groups of mouse primary hepatocytes from AAV-GFP or AAV-Trib3 mice.