Effects of polysaccharide from the fruiting bodies of Auricularia auricular on glucose metabolism in 60Co-γ-radiated mice

Radiation is known to be associated with pathology of various human diseases. This study has focused on the effect of radiation on glucose homeostasis with regard to metabolic function of liver and pancreas and the effect of polysaccharide from the fruiting bodies of Auricularia auricular (SNAAP) on glucose metabolism. The 60Co-γ-radiated mice displayed destroyed redox equilibrium, accompanied by increased blood glucose accumulation, decreased insulin and hepatic glycogen contents, impaired blood glucose tolerance ability, abnormal changes in activities of glucose metabolism-related enzymes and damaged hepatic and pancreatic function, while SNAAP can restore the disordered glucose metabolism to some extent. Increased phosphorylation of JNK and FoxO1, reduced phosphorylation of Akt and GSK-3β and increased expression of PEPCK, G6Pase and GYS2 in the liver as well as the decreased expression of PDX1, GLUT2 and IRS1 in the pancreas of radiated mice were recovered after treated with SNAAP, leading to an improved gluconeogenesis and glycogen synthesis. These findings clearly indicate that SNAAP has significant potency in radiation-induced glucose metabolism disorder through modulating the JNK pathway in the liver as well as the PDX1/GLUT2 in the pancreas.