Taurine alleviated hepatic steatosis in oleic acid-treated-HepG2 cells and rats fed a high-fat diet
Qi Song,
Jun xia Guo,
Yu xun Ma,
Tong Ou,
Jing Zhang,
Hui zi Li,
Sheng quan Mi,
Yan zhen Zhang,
Hiroaki Oda,
Wen Chen
Affiliations
Qi Song
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China; Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, 464-8601, Japan
Jun xia Guo
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China
Yu xun Ma
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China
Tong Ou
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China
Jing Zhang
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China
Hui zi Li
Department of Nutrition, PLA Rocket Force Characteristic Medical Center, Beijing, 100088, China
Sheng quan Mi
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China
Yan zhen Zhang
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China
Hiroaki Oda
Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, 464-8601, Japan; Corresponding author. Laboratory of Nutritional Biochemistry, Department of Applied Biosciences, Nagoya University, Nagoya, 464-8601, Japan.
Wen Chen
Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, 100191, China; Corresponding author. Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beituchengxi Road 197#, Haidian District, Beijing, 100191, PR China.
Taurine has been proven in many trials to alleviate the symptoms of metabolic associated fatty liver disease. Here its protective effect for hepatic steatosis and modulation of AMP-activated protein kinase and insulin signaling pathway were investigated. Steatotic HepG2 cell established with oleic acid (0.05 mmol/L), treated with taurine (5 mmol/L), dorsomorphin (10 μmol/L) for 24 h. Sprague Dawley rats were divided into regular and high-fat diet (HFD) groups, and their corresponding taurine (70 or 350 mg/kg BW/d) groups, fed for 8 weeks. In steatotic cell, taurine reduced the TG concentration and SREBP-1c, PPARγ, FAS, ACC, SCD1 protein levels, decreased phosphorylation of mTOR, IRS1 (Ser302), increased phosphorylation of AMPKα, LKB1, PI3K, Akt, ACC. While dorsomorphin eliminated taurine's TG-lowering effect. In HFD-fed rats, taurine reduced liver TG, serum TG, ALT, AST, IL-1β, IL-4, TNF-α. The effects of taurine on the main factors of fatty acid synthesis were mostly consistent with cell experiments, and the reduction of microRNAs (451, 33, 291b) was aligned with the improvement in LKB1 and AMPK expression in HFD rats. Taurine alleviated steatosis-induced inhibition of IRS1-PI3K-Akt pathway, but suppressed its positively regulated downstream factor mTOR. In parallel, taurine reduced steatosis by activating LKB1-AMPKα pathway via phosphorylation and no-phosphorylation manner, then inhibiting SREBP-1c directly or by suppressing mTOR phosphorylation.
