Protective Effect of Edgeworthia Gardneri Flos on Pancreas in Diabetes Mellitus Model Rats Induced by Tacrolimus and Its Mechanism

OBJECTIVE To research the protection effect of ethyl acetate extraction from Edgeworthia gardneri Flos(EG) on pancreas in diabetes mellitus model rats induced by tacrolimus and its mechanism. METHODS Forty SD rats were randomly divided into normal group, model group, Edgeworthia gardneri Flos group and rosiglitazone group, with 10 rats in each group. Diabetes mellitus model was established by tacrolimus intraperitoneal injection. The levels of blood glucose, insuline and HbAlc were detected. The pancreas was observed by optical microscopy and HE staining techniques. The mRNA and protein expression of pancreatic insulin receptor substrate 2(IRS-2) were detected by RT-PCR and Western blot. RESULTS The level of blood glucose, HOMA-IR, HbAlc of model group increased compared with the normal group, while the insulin and HOMA-β decreased(P<0.05). The blood glucose, HbAlc of Edgeworthia gardneri Flos group decreased compared with the model group, and the insulin and HOMA-β increased(P<0.05), IRS-2 mRNA and IRS-2 protein increased(P<0.05). HE staining pictures showed that the morphology and structure of pancreatic cells in Edgeworthia gardneri Flos group were significantly improved. The number of pancreatic cells increased, arranging neatly. And the cytoplasm was evenly distributed. CONCLUSION EG can reduce blood glucose and HbAlc formation. The mechanism may be through the insulin signal pathway in pancreas to protect β cells, increase insulin secretion, enhance glucose metabolism.