Astragalus Polysaccharides (APS) improves Free Fatty acids induced insulin resistance

Abstract

The recent increase in the prevalence of obesity has been associated with a coincident rise in the prevalence of Type 2 diabetes, whereas weight loss has been shown to decrease the risk of Type 2 diabetes. The aim of the prestent study was to examine the effects of Astragalus Polysaccharides (APS) on FFAs treated C2C12 cells, thus to reveal its further protective mechanisms. AMP‐activated protein kinase (AMPK) regulates cellular metabolism in response to the availability of energy and is therefore a target for type 2 diabetes treatment. The C2C12 cells which were pretreated with FFAs (200μmol/L) for 24h, were treated with APS(100μg/ml). The MTT experiment indicated that APS could improve the condition of C2C12 cells which were pretreated with FFAs. The expressions of total AMPK, activation of AMPK (p‐AMPK) and the activited acetyl CoA carboxylase (p‐ACC) were examined by Western blotting. Our results suggest that the total AMPK expression of C2C12 cells change little between APS group and FFAs group (p>0.05).But p‐AMPK expression increased in APS group(p<0.05) and p‐ACC expression decreased in the same group(p<0.05). This study demonstrated that APS availability affected C2C12 cells AMPK activity. The lower expression of p‐ACC could result in increasing of Fatty Acid Oxidation. Meanwhile, GLUT4 protein expression was elevated 40% by 2 days treatment with APS. In short, p‐AMPK can indirectly activate ACC and GLUT4. And AMPK can be activated by APS. Therefore, in C2C12 cells, APS improves FFAs induced insulin resistance via a AMPK‐dependent mechanism. This subject has a financial assistance by NSFC(30370673).