Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030;
Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030.
Proc Natl Acad Sci U S A. 2020 Jan 28;117(4):2076-2083. doi: 10.1073/pnas.1914267117. Epub 2020 Jan 10.
Inactivating mutations in the copper transporter result in Wilson's disease. The mouse develops hallmarks of Wilson's disease. The activity of several nuclear receptors decreased in mice, and nuclear receptors are critical for maintaining metabolic homeostasis. Therefore, we anticipated that mice would exhibit altered progression of diet-induced obesity, fatty liver, and insulin resistance. Following 10 wk on a chow or Western-type diet (40% kcal fat), parameters of glucose and lipid homeostasis were measured. Hepatic metabolites were measured by liquid chromatography-mass spectrometry and correlated with transcriptomic data. mice fed a chow diet presented with blunted body-weight gain over time, had lower fat mass, and were more glucose tolerant than wild type (WT) littermate controls. On the Western diet, mice exhibited reduced body weight, adiposity, and hepatic steatosis compared with WT controls. mice fed either diet were more insulin sensitive than WT controls; however, fasted mice exhibited hypoglycemia after administration of insulin due to an impaired glucose counterregulatory response, as evidenced by reduced hepatic glucose production. Coupling gene expression with metabolomic analyses, we observed striking changes in hepatic metabolic profiles in mice, including increases in glycolytic intermediates and components of the tricarboxylic acid cycle. In addition, the active phosphorylated form of AMP kinase was significantly increased in mice relative to WT controls. Alterations in hepatic metabolic profiles and nuclear receptor signaling were associated with improved glucose tolerance and insulin sensitivity as well as with impaired fasting glucose production in mice.
铜转运蛋白的失活突变导致威尔逊病。该小鼠表现出威尔逊病的特征。几种核受体的活性在突变小鼠中降低,而核受体对于维持代谢平衡至关重要。因此,我们预计突变小鼠会表现出饮食诱导肥胖、脂肪肝和胰岛素抵抗的进展改变。在标准饮食或西方型饮食(40%卡路里脂肪)上喂养 10 周后,测量葡萄糖和脂质代谢稳态的参数。通过液相色谱-质谱法测量肝代谢物,并将其与转录组数据相关联。在标准饮食上喂养的突变小鼠随着时间的推移体重增加缓慢,脂肪量较低,且对葡萄糖的耐受性高于野生型(WT)同窝对照。在西方型饮食上,突变小鼠的体重、肥胖程度和肝脂肪变性较 WT 对照减少。与 WT 对照相比,两种饮食喂养的突变小鼠的胰岛素敏感性更高;然而,禁食的突变小鼠在给予胰岛素后表现出低血糖,这是由于葡萄糖的反调节反应受损,肝葡萄糖生成减少。将基因表达与代谢组学分析相结合,我们观察到突变小鼠肝代谢谱的显著变化,包括糖酵解中间产物和三羧酸循环的组成部分增加。此外,与 WT 对照相比,突变小鼠中 AMP 激酶的活性磷酸化形式显著增加。肝代谢谱和核受体信号的改变与突变小鼠的葡萄糖耐量和胰岛素敏感性改善以及空腹血糖生成受损相关。