肉桂提取物对α-葡萄糖苷酶活性及糖尿病模型大鼠餐后高血糖的抑制作用

Inhibitory Effects of Cinnamon cassia Extract on α-glucosidase Activity and Postprandial Hyperglycemia in Diabetic Rats

目的:研究肉桂提取物对α-葡萄糖苷酶活性及糖尿病模型大鼠餐后高血糖的抑制作用。方法:采用大鼠肠α-葡萄糖苷酶体外活性抑制实验观察肉桂提取物的抑制作用,并采用酶动力学分析模块法对肉桂提取物抑制α-葡萄糖苷酶动力学进行研究。采用腹腔注射链脲佐菌素以复制大鼠糖尿病模型,观察肉桂提取物对麦芽糖和蔗糖负荷餐后高血糖的抑制效果。结果:体外实验表明,肉桂提取物对大鼠肠α-葡萄糖苷酶的抑制作用呈剂量依赖性,其半数抑制浓度值为529μg/ml,酶动力学数据符合竞争性抑制的特征。在体实验表明,300、600 mg/kg的肉桂提取物能明显缓解糖尿病模型大鼠麦芽糖和蔗糖负荷餐后血糖的升高,但不能缓解葡萄糖负荷餐后血糖的升高。结论:肉桂提取物可缓解餐后血糖升高,其机制可能与抑制α-葡萄糖苷酶的活性有关。

OBJECTIVE： To study the inhibitory effects of Cinnamon cassia extract on α-glucosidase activity and postprandial hy-perglycemia in diabetic rats. METHODS： The inhibitory effects of C. cassia extract were observed by studying the activity of rat intestinal α-glucosidase in vitro. The kinetics of enzyme inhibition was studied by EKM method. The diabetic rat model was induced by STZ, and therapeutic efficacy of C. cassia extracts for postprandial hyperglycemia after disaccharide loading was observed. RESULTS： in vitro studies had indicated inhibitory activity of C. cassia extract against α-glucosidase in dose-dependent manner with the IC50 value of 529 μg/ml. Enzyme kinetics data was up to a competitive mode of inhibition, in vivo animal experiments showed that C. cassia extracts （300 mg/kg and 600mg/kg） could alleviate postprandial hyperglycemia significantly in maltose and sucrose loaded STZ induced diabetic rats but not in glucose-loaded rats. CONCLUSIONS： C. cassia extracts can inhibit postprandial hyperglycemia, which may be associated with the inhibition of α-glucosidase activity.