普洱茶提取物与绿茶提取物降糖功效的研究

通过整体动物模型研究比较普洱茶提取物与绿茶提取物的降糖功效。以C57BL/6J小鼠作为对照组,将遗传性糖尿病（KKAy）小鼠随机分组,分别灌胃给予普洱茶提取物与绿茶提取物4周,以空腹血糖、血糖曲线下面积作为观察指标,比较二者的药效作用;以SD雄性大鼠一次性腹腔注射链脲佐菌素（STZ）造模糖尿病大鼠,根据初始空腹血糖值随机进行分组,连续灌胃给予普洱茶提取物与绿茶提取物4周,以空腹血糖、血糖曲线下面积和空腹血清胰岛素作为观察指标。结果显示普洱茶提取物和绿茶提取物对KKAy小鼠和STZ糖尿病模型大鼠空腹血糖均有降低作用,同时均能降低血糖曲线下面积,但是不同的是普洱茶提取物在降低动物空腹血糖和血糖曲线下面积方面要优于绿茶提取物,同时普洱茶提取物能够较模型组显著降低大鼠空腹血清胰岛素,而绿茶提取物在降低大鼠空腹血清胰岛素与模型组相比无明显差异。比较了两种茶提取物对糖尿病的体外靶酶糖醛还原酶和PTP1B的抑制作用,发现普洱茶提取物对PTP1B活性有较强的抑制作用,抑制率88.0%,绿茶提取物对该酶无抑制作用。综合实验结果表明,普洱茶提取物的降糖功效优于绿茶提取物。

Study of the Hypoglycemic Effect of Pu'er Tea and Green Tea Extracts

This study mainly researched the hypoglycemic effect of green tea extract and Pu'er tea extract by two animal models. C57BL/6J mice were selected as control group, KKAy mice were randomly grouped. They were all orally given Pu'er tea extract and green tea extract for 4 weeks. At last we selected the fasting blood glucose and AUC as objects of observation, compare the effect of green tea extract and Pu'er tea extract. We selected these two kinds of tea extract which were given orally to rats that were caused diabetic model by STZ. The results showed that both Pu'er tea extract and green tea extract could reduce the content of fasting blood glucose, the AUC at two model experiments. But the difference was that Pu'er tea extract was superior to green tea extract in fasting blood glucose and impaired AUC. At the same time Pu'er tea extract could significantly decrease the level of insulin resistance than that of green tea extract. But in decreasing the levels of fasting serum insulin, green tea extract slowed no evident difference in comparing with the model group. In the comparing of two tea extracts on diabetes target enzyme such as aldose reductase and PTP1B inhibition in vitro, the results showed that Pu'er tea extracts strongly inhibited PTP1B activity, the inhibition rate was 88.0%, green tea extract had no inhibitory effects on the enzyme. So after comprehensive evaluation the hypoglycemic effect of Pu'er tea’s extracts was better than that of green tea extracts.