Effects Of Xinjiang Kunlun Coreopsis Tinctoria Flowers Extracts On Diabetes Mellitus

Objective:To observe the effects of Xinjiang Kunlun Coreopsis tinctoria flowers extracts on a-glucosidase activity,blood glucose and lipid in vitro and in vivo.To investigate the effects and mechanism preliminarily.Methods:1)3 extracts of Xinjiang Kunlun Coreopsis tinctoria flowers were prepared by water extraction,water extraction and alcohol precipitation and macroporous absorption resins method.To observe the effects of 3 extracts of Xinjiang Kunlun Coreopsis tinctoria flowers on inhibition activity of ?-glucosidase in a-glucosidase screening assay model in vitro.2)Impaired glucose tolerance(IGT)and Diabetic mice were induced by streptozotocin(STZ).Then IGT mice were administered maltose,positive drug acarbose and the potent active extract only one time by oral gavage to monitor postprandial blood glucose in different periods.Diabetic mice were assigned to the potent active extract group and positive drug metformin group to observe changes of blood glucose,C-peptide,HbAlc and lipids of Diabetic mice.Results:1)The extracts of Xinjiang Kunlun Coriopsis ticntoria flowers showed obvious inhibition effecacy on ?-glucosidase screening assay model in vitro.The extract? was the most effective inhibitor as the IC50 is minimum in vitro.The results of postprandial blood glucose showed that extract? cannot decrease postprandial blood glucose levels in IGT mice completely compared with the vehicle group(P>0.05).2)But the extract?can reduce blood glucose,triglycerides,increase serum C-peptide levels(P<0.01)and decrease HbAlc,total cholesterol levels(P<0.05)in diabetic mice for 30 days treatment.Conclusion:Xinjiang Kunlun Coriopsis ticntoria flowers extracts can significantly inhibit a-glucosidase activity in vitro.Among of them,extract? has the most potent inhibition on a-glucosidase activity in vitro.it cannot decrease postprandial hyperglycemia in IGT mice but reduce blood glucose,triglycerides,total cholesterol and HbAlc levels and elevate C-peptide levels in diabetic mice.