Abstract: The aim of this study was to investigate the hypoglycemic effect of Pu′er tea extract combined with pioglitazone on diabetic model rat induced by STZ and clarify the synergistic effect of Pu′er tea extract with hypoglycemic drugs and the amount of hypoglycemic drugs could be reduced under the premise to control blood glucose. According to the blood glucose levels and the different ways of Pu′er tea extract combined with pioglitazone, all animals were divided into different groups including control, model, high P, low P, HP+LPTE, HP+HPTE, LP+LPTE, LP+HPTE, orally administered twice a day for consecutive 4 weeks. Animals’ status was observed during the test, and rat tail veins were weekly acupunctured to measure fasting blood glucose. The glucose tolerance, GSP and insulin levels in serum were determined in fourth week and insulin sensitivity index was calculated. The results showed that Pu′er tea extract combined with mixed medication pioglitazone could significantly suppress fasting blood glucose, lower blood glucose at 30βmin, 60βmin, 120βmin after administration of glucose, and reduce the AUC as compared with other groups. Additionally, serum GSP levels were also reduced after treatment with Pu′er tea extract combined with pioglitazone. These results suggest that pioglitazone combined with pu′er tea extract could reduce the amount of pioglitazone without reducing pioglitazone’s hypoglycemic effect.

Key words: Pu′er tea extract;, hypoglycemic, drug combination, pioglitazone, tolerance