Curcumin exerts beneficial role on insulin resistance through modulation of SOCS3 and Rac-1 pathways in type 2 diabetic rats

The present study examined the anti-diabetic effect of curcumin (cur) on insulin resistance (IR) through modulation of SOCS3 and Rac-1 pathways in rats with type 2 diabetes (T2D) induced by high-fat diet (HFD) and streptozotocin (STZ). The expression pattern of proteins and genes associated with insulin signaling pathways was measured by western blot and real-time PCR. Moreover, biomarkers of the oxidative stress in skeletal muscles were measured. Diabetic rats showed increased malondialdehyde (MDA) in skeletal muscles with a concomitant decrease in superoxide dismutase (SOD), and catalase (CAT) activities. Moreover, diabetic rats showed heightened levels of SOCS-3 and STAT-3 expression, as well as decreased IRS-1, Rac1, and Rac-GTP in skeletal muscles. The level of antioxidant enzyme activities reached the baseline after the treatment with cur. The anti-diabetic effect of cur was exerted by a reduction in the expression of STAT-3, SOCS3, as well as the elevation in IRS-1, Rac1, and Rac-GTP.