Hypoglycemic effect of whole grain diet in C57BL/KsJ-db/db mice by activating PI3K/Akt and AMPK pathways

Type II diabetes mellitus (T2DM), characterized by abnormal blood glucose level, is a metabolic disease caused by pancreatic β-cell dysfunction and insulin resistance. Previous studies have reported that whole grain intake alleviated various metabolic syndromes. Here, the hypoglycemic effect of whole grain diet (WGD) on type II diabetes was investigated in C57BL/KsJ-db/db mice. WGD improved the regulation of fasting and postprandial blood glucose levels and reduced weight gain and lipid accumulation. On the molecular level, WGD up-regulated the glucose transporter type 4 and stimulated the insulin receptor substrate 1/phosphoinositide 3-kinase ((PI3K)/Akt) pathway. WGD stimulated the AMP-activated protein kinase (AMPK)/p38/Acetyl-CoA carboxylate pathway related to lipid metabolism and glucose uptake, and down-regulated the pro-inflammatory cytokines, C-reactive protein, interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha. Taken together, whole grains can be employed as functional food ingredients to alleviate T2DM by enhancing the PI3K/Akt and AMPK pathways.