Akinrotimi Oludemilade, Riessen Ryan, VanDuyne Philip, Park Jung Eun, Lee Yoon Kwang, Wong Lee-Jun, Zavacki Ann M, Schoonjans Kristina, Anakk Sayeepriyadarshini
Department of Molecular and Integrative Physiology, University of Illinois, Urbana-Champaign, Urbana, IL.
Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH.
Hepatology. 2017 Dec;66(6):1854-1865. doi: 10.1002/hep.29305. Epub 2017 Oct 30.
Nuclear receptors farnesoid X receptor (FXR) and small heterodimer partner (SHP) are important regulators of bile acid, lipid, and glucose homeostasis. Here, we show that global Fxr Shp double knockout (DKO) mice are refractory to weight gain, glucose intolerance, and hepatic steatosis when challenged with high-fat diet. DKO mice display an inherently increased capacity to burn fat and suppress de novo hepatic lipid synthesis. Moreover, DKO mice were also very active and that correlated well with the observed increase in phosphoenolpyruvate carboxykinase expression, type IA fibers, and mitochondrial function in skeletal muscle. Mechanistically, we demonstrate that liver-specific Shp deletion protects against fatty liver development by suppressing expression of peroxisome proliferator-activated receptor gamma 2 and lipid-droplet protein fat-specific protein 27 beta.
These data suggest that Fxr and Shp inactivation may be beneficial to combat diet-induced obesity and uncover that hepatic SHP is necessary to promote fatty liver disease. (Hepatology 2017;66:1854-1865).
核受体法尼酯X受体(FXR)和小异二聚体伴侣蛋白(SHP)是胆汁酸、脂质和葡萄糖稳态的重要调节因子。在此,我们表明,全局Fxr和Shp双敲除(DKO)小鼠在高脂饮食刺激下对体重增加、葡萄糖不耐受和肝脂肪变性具有抗性。DKO小鼠表现出内在的脂肪燃烧能力增强以及肝脏从头合成脂质的能力受到抑制。此外,DKO小鼠也非常活跃,这与观察到的骨骼肌中磷酸烯醇丙酮酸羧激酶表达增加、I型A纤维和线粒体功能增强密切相关。从机制上讲,我们证明肝脏特异性Shp缺失通过抑制过氧化物酶体增殖物激活受体γ2和脂滴蛋白脂肪特异性蛋白27β的表达来预防脂肪肝的发生。
这些数据表明,Fxr和Shp失活可能有助于对抗饮食诱导的肥胖,并揭示肝脏SHP是促进脂肪肝疾病所必需的。(《肝脏病学》2017年;66:1854 - 1865)