Antidiabetic Properties and Possible Mechanism of the Traditional Chinese Medicine Yi Qi Yang Yin Recipe in Db/db Mice

Background Yi Qi Yang Yin Recipe (YQYY) is a well-known clinical prescription used in Traditional Chinese Medicine (TCM) that ameliorates type 2 diabetes. The aim of the present study was to comprehensively evaluate the efficacy of YQYY granules and explore their mechanism of action. Methods db/db mice were studied as an animal model of type 2 diabetes. After administered with YQYY for eight weeks, food and water consumption, levels of fasting blood glucose, glycosylated serum protein, and liver and pancreas tissue morphology were investigated. In addition, RT-PCR and Westernblot analysis were used to determine the expression of genes and proteins related to glycogen synthesis and gluconeogenesis pathways in the liver. Results YQYY resulted in significantly reduced food and water consumption, and lower fasting blood glucose and glycated serum protein levels. Furthermore, the proliferation of α-cells in db/db mouse pancreatic tissue decreased and liver tissue morphology was significantly ameliorated. YQYY upregulated the expression of phosphorylated GSK-3β and GS proteins in db/db mouse liver tissue, and promoted the synthesis of liver glycogen. Additionally, AMPK was activated, PEPCK and G6Pase gene expression levels decreased, and consequently, gluconeogenesis in the liver was inhibited. Therefore, YQYY improves diabetic phenotyp, suggesting that YQYY could be a prospective agent for preventing and treatment diabetes .