Project description:NADPH-cytochrome P450 reductase (CPR) is important for the functions of many enzymes, such as microsomal cytochrome P450 (P450) monooxygenases and heme oxygenases. Two mouse models with deficient CPR expression in adults were recently generated in this laboratory: liver-Cpr-null (with liver-specific Cpr deletion) (Gu et al., J. Biol. Chem., 278, 25895–25901, 2003) and Cpr-low (with reduced CPR expression in all organs examined) (Wu et al. J. Pharmacol. Expt. Ther. 312, 35-43, 2005). The phenotypes included a reduced serum cholesterol level and an induction of hepatic P450 in both models, and hepatomegaly and fatty liver in the liver-Cpr-null mouse alone. Our aim was to identify hepatic gene-expression changes related to these phenotypes. Cpr-lox mice, which have normal CPR expression (Wu et al., Genesis, 36, 177-181, 2003.), were used as the control in microarray analysis. A detailed analysis of the gene-expression changes in lipid metabolism and transport pathways revealed potential mechanisms, such as an increased activation of constitutive androstane receptor (CAR) and a decreased activation of peroxisomal proliferators activated receptor alpha (PPAR-gamma) by precursors of cholesterol biosynthesis, that underlie common changes (e.g., induction of multiple P450s and inhibition of genes for fatty acids metabolism) in response to CPR-loss in the two mouse models. Moreover, we also uncovered model-specific gene-expression changes, such as the induction of a lipid translocase (CD36 antigen) and the suppression of carnitine O-palmitoyltransferase 1 (CPT1a) and acyl-CoA synthetase long-chain family member 1 (Acsl1), that are potentially responsible for the severe hepatic lipidosis observed in liver-Cpr-null, but not Cpr-low mice. Keywords = Cytochrome P450 Keywords = NADPH-cytochrome P450 reductase Keywords = transgenic mice Keywords = liver Keywords = nuclear receptor Keywords: other
Project description:NADPH-cytochrome P450 reductase (CPR) is important for the functions of many enzymes, such as microsomal cytochrome P450 (P450) monooxygenases and heme oxygenases. Two mouse models with deficient CPR expression in adults were recently generated in this laboratory: liver-Cpr-null (with liver-specific Cpr deletion) (Gu et al., J. Biol. Chem., 278, 25895-25901, 2003) and Cpr-low (with reduced CPR expression in all organs examined) (Wu et al. J. Pharmacol. Expt. Ther. 312, 35-43, 2005). The phenotypes included a reduced serum cholesterol level and an induction of hepatic P450 in both models, and hepatomegaly and fatty liver in the liver-Cpr-null mouse alone. Our aim was to identify hepatic gene-expression changes related to these phenotypes. Cpr-lox mice, which have normal CPR expression (Wu et al., Genesis, 36, 177-181, 2003.), were used as the control in microarray analysis. A detailed analysis of the gene-expression changes in lipid metabolism and transport pathways revealed potential mechanisms, such as an increased activation of constitutive androstane receptor (CAR) and a decreased activation of peroxisomal proliferators activated receptor alpha (PPARï?¡) by precursors of cholesterol biosynthesis, that underlie common changes (e.g., induction of multiple P450s and inhibition of genes for fatty acids metabolism) in response to CPR-loss in the two mouse models. Moreover, we also uncovered model-specific gene-expression changes, such as the induction of a lipid translocase (CD36 antigen) and the suppression of carnitine O-palmitoyltransferase 1 (CPT1a) and acyl-CoA synthetase long-chain family member 1 (Acsl1), that are potentially responsible for the severe hepatic lipidosis observed in liver-Cpr-null, but not Cpr-low mice.
Project description:Microarray analysis to examine the relationship between hepatic phenotype and changes in gene expression in cytochrome P450 reductase (CPR) null mice. Keywords: ordered
Project description:Microarray analysis to examine the relationship between hepatic phenotype and changes in gene expression in cytochrome P450 reductase (CPR) null mice.
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility.
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Keywords: wildtype vs Myc-null
Project description:Acetaminophen is a widely used antipyretic and analgesic drug, and its overdose is the leading cause of drug-induced acute liver failure. This study aimed to investigate the effect and mechanism of Lacticaseibacillus casei Shirota (LcS), an extensively used and highly studied probiotic, on acetaminophen-induced acute liver injury. C57BL/6 mice were gavaged with LcS suspension or saline once daily for 7 days before the acute liver injury was induced via intraperitoneal injection of 300 mg/kg acetaminophen. The results showed that LcS significantly decreased acetaminophen-induced liver and ileum injury, as demonstrated by reductions in the increases in aspartate aminotransferase, total bile acids, total bilirubin, indirect bilirubin and hepatic cell necrosis. Moreover, LcS alleviated the acetaminophen-induced intestinal mucosal permeability, elevation in serum IL-1α and lipopolysaccharide, and decreased levels of serum eosinophil chemokine (eotaxin) and hepatic glutathione levels. Furthermore, analysis of the gut microbiota and metabolome showed that LcS reduced the acetaminophen-enriched levels of Cyanobacteria, Oxyphotobacteria, long-chain fatty acids, cholesterol and sugars in the gut. Additionally, the transcriptome and proteomics showed that LcS mitigated the downregulation of metabolism and immune pathways as well as glutathione formation during acetaminophen-induced acute liver injury. This is the first study showing that pretreatment with LcS alleviates acetaminophen-enriched acute liver injury, and it provides a reference for the application of LcS.
Project description:The ketogenic diet has been successful in promoting weight loss among patients that have struggled with weight gain. This is due to the cellular switch in metabolism that utilizes liver-derived ketone bodies for the primary energy source rather than glucose. Fatty acid transport protein 2 (FATP2) is highly expressed in liver, small intestine, and kidney where it functions in both the transport of exogenous long chain fatty acids (LCFA) and in the activation to CoA thioesters of very long chain fatty acids (VLCFA). We have completed a multi-omic study of FATP2-null (Fatp2-/-) mice maintained on a ketogenic diet (KD) or paired control diet (CD), with and without a 24-hour fast (KD-fasted and CD-fasted) to address the impact of deleting FATP2 under high-stress conditions. Control (wt/wt) and Fatp2-/- mice were maintained on their respective diets for 4-weeks. Afterwards, half the population was sacrificed while the remaining were fasted for 24-hours prior to sacrifice. We then performed paired-end RNA-sequencing on the whole liver tissue to investigate differential gene expression. The differentially expressed genes mapped to ontologies such as the metabolism of amino acids and derivatives, fatty acid metabolism, protein localization, and components of the immune system’s complement cascade, and were supported by the proteome and histological staining.
Project description:Sex differences in liver gene expression are dictated by sex-differences in circulating growth hormone (GH) profiles. Presently, the pituitary hormone dependence of mouse liver gene expression was investigated on a global scale to discover sex-specific early GH response genes that might contribute to sex-specific regulation of downstream GH targets and to ascertain whether intrinsic sex-differences characterize hepatic responses to plasma GH stimulation. RNA expression analysis using 41,000-feature microarrays revealed two distinct classes of sex-specific mouse liver genes: genes subject to positive regulation (class-I) and genes subject to negative regulation by pituitary hormones (class-II). Genes activated or repressed in hypophysectomized (Hypox) mouse liver within 30-90min of GH pulse treatment at a physiological dose were identified as direct targets of GH action (early response genes). Intrinsic sex-differences in the GH responsiveness of a subset of these early response genes were observed. Notably, 45 male-specific genes, including five encoding transcriptional regulators that may mediate downstream sex-specific transcriptional responses, were rapidly induced by GH (within 30min) in Hypox male but not Hypox female mouse liver. The early GH response genes were enriched in 29 male-specific targets of the transcription factor Mef2, whose activation in hepatic stellate cells is associated with liver fibrosis leading to hepatocellular carcinoma, a male-predominant disease. Thus, the rapid activation by GH pulses of certain sex-specific genes is modulated by intrinsic sex-specific factors, which may be associated with prior hormone exposure (epigenetic mechanisms) or genetic factors that are pituitary-independent, and could contribute to sex-differences in predisposition to liver cancer or other hepatic pathophysiologies.