Investigating the Effects of Rosiglitazone and Epigallocatechin-3-Gallate on PGC-1α protein expression in Palmitate-induced Insulin Resistant C2C12 skeletal Muscle Cells

Alterations in lipids metabolism are one of the important mechanisms for the treatment of insulin resistance and، hence for type 2 diabetes. On the other hand، PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]>، as a key regulator of mitochondrial biogenesis and function، by increasing β-oxidation of lipids plays an important role in improving insulin sensitivity. In the present study، the effects of Epigallocatechin-3-Gallate (EGCG)، an anti-obesity and enhancer of lipid catabolism agent، on PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]> protein expression was examined and compared with the anti-diabetic drug Rosiglitazone (RGZ). After differentiation of C2C12 myoblasts to myotubes، insulin resistance was induced by palmitate treatment. Afterward، PGC-1α protein expression was examined using the western blot method before and after treatment with insulin and after EGCG and RGZ treatment. Palmitate treatment significantly decreased PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]>protein expression in the C2C12 cells (P=0. 001). Treatment of these cells with EGCG had no significant effect on the PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]> protein expression (P=0. 67)، whereas treatment with RGZ significantly increased expression of this gene at protein level (P=0. 003). In addition، this significant increase in PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]> protein expression was maintained by simultaneous treatment with EGCG and RGZ (P=0. 001). Our results showed that the effect of EGCG on PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]> protein expression was not significant، whereas RGZ significantly improved the palmitate-induced reduction of PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]> protein expression. Overall، it seems that anti-diabetic effect of EGCG is not exerted through its effect on the expression of PGC-1 supportFields]> QUOTE AWT IMAGE α supportFields]> gene، in contrast to that of RGZ.