Activation of farnesoid X receptor promotes triglycerides lowering by suppressing phospholipase A2 G12B expression. (15th November 2016)

• Record Type: Journal Article
• Authors: Liu, Qingli; Yang, Meng; Fu, Xuekun; Liu, Renzhong; Sun, Caijun; Pan, Haobo; Wong, Chi-Wai; Guan, Min
• Is Part Of: Molecular and cellular endocrinology. Volume 436(2016)
• Page Start: 93
• Page End: 101
• Publication Date: 2016-11-15
• Subjects: Triglyceride -- Very low-density lipoprotein -- Phospholipase A2 G12B -- Farnesoid X receptor; Endocrinology -- Periodicals; Molecular biology -- Periodicals; Cytology -- Periodicals; Endocrinology -- Periodicals; Hormones -- Periodicals; Endocrinologie -- Périodiques; Cytology; Endocrinology; Molecular biology; Periodicals; 573.4
• DOI: 10.1016/j.mce.2016.07.027
• Languages: English
• ISSNs: 0303-7207

Abstract

Abstract: As a novel mediator of hepatic very low-density lipoproteins (VLDL) secretion, phospholipase A2 G12B (PLA2G12B) is transcriptionally regulated by hepatocyte nuclear factor-4 alpha (HNF-4α). Farnesoid X receptor (FXR) plays a critical role in maintaining bile acids and triglycerides (TG) homeostasis. Here we report that FXR regulates serum TG level in part through PLA2G12B. Activation of FXR by chenodeoxycholic acid (CDCA) or GW4064 significantly decreased PLA2G12B expression in HepG2 cells. PLA2G12B expression was transcriptionally repressed due to an FXR-mediated up-regulation of small heterodimer partner (SHP) which functionally suppresses HNF-4α activity. We found that hepatic PLA2G12B expression was suppressed and serum TG level reduced in high fat diet mice treated with CDCA. Concurrently, CDCA treatment lowered hepatic VLDL-TG secretion. Our data demonstrate that activation of FXR promotes TG lowering, not only by decreasing de novo lipogenesis but also reducing hepatic secretion of TG-rich VLDL particles in part through suppressing PLA2G12B expression. Highlights: FXR activation suppresses PLA2G12B promoter reporter expression. FXR agonists reduce PLA2G12B expression in HepG2. FXR ligand CDCA lowers hepatic VLDL secretion through decreased PLA2G12B and MTP.