The mechanisms of free fatty acid (FFA)-induced peripheral insulin resistance remain elusive. This study aimed to investigate the effect of palmitate, a saturated fatty acid, on glucose metabolism in C2C12 myotubes, and to explore the underlying mechanisms. In it, palmitate decreased insulin-stimulated glucose uptake and consumption in a dose-dependent manner, and it reduced the insulin-stimulated phosphorylation of Akt at Thr308 and Ser473, but had no effect on the protein expression of PI3K-p85 or the activity of PI3K. Additionally, it inhibited the insulin-stimulated phosphorylation of Src at Tyr416, causing a reduction in the Src-mediated phosphorylation of Akt. Inhibition of Src by PP2 resulted in decreases in insulin-stimulated glucose uptake and phosphorylation of Src at Tyr416 and Akt at Thr308 and Ser473. The findings indicate that palmitate contributes to insulin resistance by inhibiting the Src-mediated phosphorylation of Akt in C2C12 myotubes, and this provides insight into the molecular mechanisms of FFA-induced insulin resistance.
[1]Fudan Univ, Inst Chinese Integrat Med, Huashan Hosp, Shanghai 200040, Peoples R China.
[2]Guangxi Tradit Chinese Med Univ, Guangxi Sci Expt Ctr Tradit Chinese Med, Nanning 530001, Peoples R China.
[3]Shanghai Tradit Chinese Med Univ, Longhua Hosp, Dept Endocrinol, Shanghai 200040, Peoples R China.
[4]Shanghai Tradit Chinese Med Univ, Shanghai Acad Tradit Chinese Med, Yueyang Integrat Med Hosp, Inst Integrated Med Clin, Shanghai 200040, Peoples R China.
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