Project description:The liver is a major site for synthesis, storage and redistribution of carbohydrates, proteins and lipids. In addition, it is well-known that maternal obesity (MO) increases risk of offspring cardiovascular disease (CVD), diabetes and obesity. However, the mechanisms by which the MO intrauterine environment predisposes offspring to CVD and metabolic dysregulation are unknown. The goal of this study was to assess the impact of MO on primate fetal liver and identify underlying molecular mechanisms by which MO increases disease risk. The goal of this study was to identify candidate molecular mechanisms underlying MO in the near-term non-human primate (NHP) fetal liver. This is the first study of NHP fetal MO livers using unbiased transcriptome analysis to quantify hepatic gene expression, identify dysregulated signaling pathways and potential miRNAs regulating the disrupted metabolic processes. Unbiased gene (arrays) and microRNA (miRNA; small RNA-Seq) abundances were quantified in near-term (0.9 Gestation (0.9G)) baboon fetal livers (control (CON) = 6; MO = 5) and subjected to pathway and network analyses (GeneSifter, Ingenuity® Pathway Analysis (IPA)) to identify a coordinated molecular response to MO. Lipid and glycogen content (CON = 16; MO = 16) were quantified by Computer Assisted Stereology Toolbox (CAST) in 0.9G livers. Pairwise comparisons showed 933 differentially expressed genes between CON and MO livers: 350 genes were upregulated and 583 were downregulated. Pathway analysis revealed upregulation of Wnt/β-catenin signaling and downregulation of tricarboxylic acid (TCA) cycle, proteasome, oxidative phosphorylation and glycolysis pathways in MO fetal livers compared with CON. Inversely expressed miRNAs that target genes in these pathways provide additional support for the importance of these pathways in fetal liver metabolic regulation. Consistent with the observed pathway changes in MO, we found hepatic lipid content was threefold greater in MO than CON fetal livers (p=0.02). Molecular genetic analyses of CON and MO fetal baboon livers revealed dysregulation of Wnt/β-catenin signaling, TCA cycle, proteasome, oxidative phosphorylation and glycolysis pathways in MO livers, all of which are central to fatty acid metabolism and lipid storage. The marked lipid accumulation in MO fetal livers supports our hypothesis that dysregulation of these pathways detrimentally impacts lipid management. Furthermore, our findings demonstrate the detrimental impact of MO on fetal liver development and suggest impaired hepatic function prior to birth.
Project description:The liver is a major site for synthesis, storage and redistribution of carbohydrates, proteins and lipids. In addition, it is well-known that maternal obesity (MO) increases risk of offspring cardiovascular disease (CVD), diabetes and obesity. However, the mechanisms by which the MO intrauterine environment predisposes offspring to CVD and metabolic dysregulation are unknown. The goal of this study was to assess the impact of MO on primate fetal liver and identify underlying molecular mechanisms by which MO increases disease risk. The goal of this study was to identify candidate molecular mechanisms underlying MO in the near-term NHP fetal liver. This is the first study of NHP fetal MO livers using unbiased transcriptome analysis to quantify hepatic gene expression, identify dysregulated signaling pathways and potential miRNAs regulating the disrupted metabolic processes. Unbiased gene (arrays) and microRNA (miRNA; small RNA-Seq) abundances were quantified in near-term (0.9 Gestation (0.9G)) baboon fetal livers (control (CON) = 6; MO = 5) and subjected to pathway and network analyses (GeneSifter, Ingenuity® Pathway Analysis (IPA)) to identify a coordinated molecular response to MO. Lipid and glycogen content (CON = 16; MO = 16) were quantified by Computer Assisted Stereology Toolbox (CAST) in 0.9G livers.Pairwise comparisons showed 933 differentially expressed genes between CON and MO livers: 350 genes were upregulated and 583 were downregulated. Pathway analysis revealed upregulation of Wnt/β-catenin signaling and downregulation of tricarboxylic acid (TCA) cycle, proteasome, oxidative phosphorylation and glycolysis pathways in MO fetal livers compared with CON. Inversely expressed miRNAs that target genes in these pathways provide additional support for the importance of these pathways in fetal liver metabolic regulation. Consistent with the observed pathway changes in MO, we found hepatic lipid content was threefold greater in MO than CON fetal livers (p=0.02). Molecular genetic analyses of CON and MO fetal baboon livers revealed dysregulation of Wnt/β-catenin signaling, TCA cycle, proteasome, oxidative phosphorylation and glycolysis pathways in MO livers, all of which are central to fatty acid metabolism and lipid storage. The marked lipid accumulation in MO fetal livers supports our hypothesis that dysregulation of these pathways detrimentally impacts lipid management. Furthermore, our findings demonstrate the detrimental impact of MO on fetal liver development and suggest impaired hepatic function prior to birth.
Project description:Maternal obesity in mice negatively affects placental functionand maternal and fetal liver function. We performed a global proteomic analysis using a liquid-chromatography/mass-spectrometry system to investigate total and phosphorylated proteins in the placenta and fetal liver in a mouse model that combines maternal obesity with maternal androgen excess to identify changes in molecular pathways that might promote diseases in adulthood.
Project description:Introduction: Diet-induced obesity is associated with hepatic lipid accumulation, increased circulating levels of endotoxin, and chronic low grade inflammation. Hepatic lipid accumulation and resulting non-alcoholic fatty liver disease (NAFLD) can exacerbate systemic inflammation further contributing to neurodegenerative effects. Maple Syrup Extract (MSX), could be a potential source of beneficial phytonutrients capable of mitigating these adverse inflammatory processes from occurring. Methods: A pilot scale diet-induced obesity study with male C57BL/6 mice fed either a standard diet (10% kcal from fat) or a high fat diet (45% kcal from fat) with or without MSX at a dose of 0.5% w/w incorporated into feed for 12 weeks. Livers and whole hippocampi were excised for multiplex gene expression analysis of inflammatory, fatty liver, and neurodegenerative disease associated genes. Livers were scored for lipid accumulation and lipid moieties were quantified. Results: In hepatic tissue, MSX protected against lipid accumulation and inflammatory progression. MSX supplementation significantly reduced lipid accumulation scores as well as gene expression of lipid uptake, storage, and inflammatory associated genes. In the hippocampus, MSX supplementation in HFD feed significantly reduced the gene expression of pro-inflammatory, death receptor ligands, anti-oxidant response enzymes, macrophage receptors, and leptin receptor. Conclusions: In the liver, MSX prevents gross hepatic lipid accumulation and suppresses both pro-inflammatory and lipid storage associated genes. In the hippocampus, MSX may act on pro-inflammatory gene expression but TNF mediated death receptor pathways in addition to modulating leptin receptor signaling.