Antidiabetic activity of a polysaccharide-protein complex from Asian Clam (Corbicula fluminea) in streptozotoxin-induced diabetic rats and underlying mechanism
The antidiabetic activity and potential underlying mechanism of a polysaccharide-protein complex (PSP) from Corbicula fluminea was determined in streptozotoxin (STZ)-induced diabetic rats. PSP exhibited inhibitory activity (in vitro) against α-glucosidase and α-amylase via reversible competitive inhibition pattern with a stronger inhibition on α-glucosidase. Dietary administration of PSP had potent antidiabetic activities in vivo, which was evidenced by that PSP alleviated body weight loss and organ injures, reduced fasting blood glucose, elevated glucose tolerance, and ameliorated lipid metabolism and hepatic functions, as well as attenuated oxidative stress in STZ-treated diabetic rats. Furthermore, our results demonstrated that the antidiabetic activities of PSP were associated with activation of the phosphoinositide 3-kinase/protein kinase B signaling pathway in STZ-treated rats. These findings supported the potential of PSP to be used as a functional ingredient for functional and medical foods to inhibit diabetes mellitus and its complications.