Study of the antidiabetic action of cinnamon extract on cell culture of 3T3-Li adipocytes

Abstract

Insulin binds to the extracellular -subunit of the insulin receptor, and induces a conformational change in the kinase domain of the trans membrane β-subunit resulting in activation of insulin receptor tyrosine kinase, an essential step for the downstream insulin signalling events. In type 2 diabetes, part of the insulin resistance is due to inability of insulin to activate the receptor kinase activity. The activity of cinnamtannin B1 on phosphorylation of insulin receptor was analyzed using western blot technique. Cnnnamtannin B 1 stimulated phosphorylation of insulin receptor β-subunit. There was no phosphorylation of insulin receptor observed in 3T3-L1 preadipocytes. The activity of cinnamtannin B1 in stimulating phosphorylation was inhibited by wortmannin and cytochalasin B. In contrast, sodium orthovanadate stimulated phosphorylation of insulin receptor.