The effect of Sirt1 in chromium-mediated insulin action

• Main Authors: Yi-Ting Chen, 陳怡婷
• Other Authors: 陳文英
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/03918845125189558982

碩士 === 國立中興大學 === 獸醫學系暨研究所 === 103 === Insulin resistance is the major pathology of type 2 diabetes. High levels of free fatty acids may affect the glucose metabolism and impact the insulin signaling. Trivalent chromium (Cr) is an essential nutrient required for glucose and lipid metabolism. Studies reveal that tissue Cr levels of subjects with diabetes are lower than those of normal control subjects. However, Cr supplementation improved hyperglycemia by enhancing insulin sensitivity in diabetic patients. Growing evidence shows that Sirt1 can ameliorate insulin resistance by enhancing insulin signaling pathways in insulin-sensitive organs. However, it is unclear whether the effect of Cr in insulin signaling is mediated by Sirt1. In this study, we exposing C2C12 mouse myoblast cells to palmitic acid (PA) to setup an in vitro cell model of insulin resistance. The results showed that Cr supplementation increases insulin signaling and Sirt1 expression in C2C12 insulin resistance cell model. Sirt1 inhibitor nicotinamide (NA) abrogated the effects of Cr on insulin signaling. Our data suggest that Cr supplementation can provide a beneficial effect in diabetic subjects by enhancing insulin signaling. The improvement in insulin signaling by Cr maybe mediated by Sirt1.