蛇含委陵菜总黄酮的体外和体内降血糖效果研究

Antihyperglycemic Effect of Total Flavonoids from Potentilla kleiniana Wight et Arn. in vitro and in vivo

目的:探讨蛇含委陵菜总黄酮(total flavonoid Potentilla kleiniana Wight et Arn.,TFP)的体外和体内降血糖效果。方法:TFP是利用超声波循环提取及D-101大孔树脂纯化得到。体外降血糖效果主要考察TFP对α-葡萄糖苷酶和α-淀粉酶以及对氧化自由基吸收能力(oxygen radical absorption capacity,ORAC)的抑制影响,体内降血糖效果是利用链脲佐菌素诱导小鼠糖尿病模型,100、200、400mg/(kg·d)的不同剂量治疗4周,每周末尾部动脉取血测定血糖,4周后眼眶取血测定血清胰岛素,处死取肝脏测定肝糖原和丙酮酸激酶的含量。结果:体外降血糖效果发现,TFP对α-葡萄糖苷酶具有较强的抑制活性并且体现剂量依赖性,而对α-淀粉酶的抑制活性不高,对ORAC的抑制活性较高,而体内降血糖效果发现,TFP不同剂量对糖尿病小鼠具有很好的降血糖效果,特别是400mg/(kg·d)的剂量组降血糖效果非常明显,血清胰岛素的含量得到明显提高,另发现,TFP有利于丙酮酸激酶的分泌,从而促使肝糖原的合成,使得肝糖原的含量经过治疗后含量增加。结论:蛇含委陵菜总黄酮是一种具有很大潜力的降血糖和抗氧化的天然产物。

Objective: To explore the hypoglycemic effect of total flavonoids from Potentilla kleiniana Wight et Arn.(TFP) in vitro and in vivo. Methods: TFP was purified by cyclic ultrasonic extraction and D-101 macroporous resin adsorption.in vitro tests were carried out to assess the inhibitory effect on α-glucosidase and α-amylase and oxygen radical absorption capacity(ORAC) of TFP. The in vivo antihyperglycemic effect was investigated by administration of streptozotocininduced diabetic mouse model at 100, 200 and 400 mg/(kg·d) body weight for 4 consecutive weeks. The venous blood glucose was measured at the end of each week. After four weeks, the insulin level in orbital blood serum was measured and all the animals were sacrificed for the determination of liver glycogen and pyruvate kinase(PK). Results: The inhibitory activity of TFP on α-glucosidase was strong in a dose-dependent manner, while the inhibitory activity on α-amylase was not strong. TFP had a strong ORAC activity. It exhibited a good hypoglycemic effect in diabetic mice at each dose and this effect was particularly noticeable at 400 mg/(kg·d) body weight. The serum insulin level was significantly increased and the secretion of pyruvate kinase was greatly enhanced, thus contributing to glycogen synthesis and increasing glycogen content after treatment. Conclusion: Potentilla kleiniana Wight et Arn. is a natural herb with potential hypoglycemic and antioxidant activities.