Jun-Xian Wang , Yuan Luo , Samwel Mchele Limbu , Yu-Cheng Qian , Yan-Yu Zhang , Rui-Xin Li , Wen-Hao Zhou , Fang Qiao , Li-Qiao Chen , Mei-Ling Zhang , Zhen-Yu Du
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引用次数: 0
Abstract
The solute carrier family 25 member 1 (Slc25a1)-dependent mitochondrial citrate shuttle is responsible for exporting citrate from the mitochondria to the cytoplasm for supporting lipid biosynthesis and protein acetylation. Previous studies on Slc25a1 concentrated on pathological models. However, the importance of Slc25a1 in maintaining metabolic homeostasis under normal nutritional conditions remains poorly understood. Here, we investigated the mechanism of mitochondrial citrate shuttle in maintaining lipid metabolism homeostasis in male Nile tilapia (Oreochromis niloticus). To achieve the objective, we blocked the mitochondrial citrate shuttle by inhibiting Slc25a1 under normal nutritional conditions. Slc25a1 inhibition was established by feeding Nile tilapia with 250 mg/kg 1,2,3-benzenetricarboxylic acid hydrate for 6 weeks or intraperitoneal injecting them with dsRNA to knockdown slc25a1b for 7 days. The Nile tilapia with Slc25a1 inhibition exhibited an obesity-like phenotype accompanied by fat deposition, liver damage and hyperglycemia. Moreover, Slc25a1 inhibition decreased hepatic citrate-derived acetyl-CoA, but increased hepatic triglyceride levels. Furthermore, Slc25a1 inhibition replenished cytoplasmic acetyl-CoA through enhanced acetate pathway, which led to hepatic triglycerides accumulation. However, acetate-derived acetyl-CoA caused by hepatic Slc25a1 inhibition did not activate de novo lipogenesis, but rather modified protein acetylation. In addition, hepatic Slc25a1 inhibition enhanced fatty acids esterification through acetate-derived acetyl-CoA, which increased Lipin1 acetylation and its protein stability. Collectively, our results illustrate that inhibiting mitochondrial citrate shuttle triggers lipid anabolic remodeling and results in lipid accumulation, indicating the importance of mitochondrial citrate shuttle in maintaining lipid metabolism homeostasis.
期刊介绍:
Devoted to advancements in nutritional sciences, The Journal of Nutritional Biochemistry presents experimental nutrition research as it relates to: biochemistry, molecular biology, toxicology, or physiology.
Rigorous reviews by an international editorial board of distinguished scientists ensure publication of the most current and key research being conducted in nutrition at the cellular, animal and human level. In addition to its monthly features of critical reviews and research articles, The Journal of Nutritional Biochemistry also periodically publishes emerging issues, experimental methods, and other types of articles.