Zhang Su-jun, Qu Wei-jing, Zhong Shu-yun
School of Life Science, East China Normal University, Shanghai 200062, China.
Zhongguo Zhong Yao Za Zhi. 2006 Jun;31(11):910-3.
To determine the effects of saponins from Tribulus terrestris (STT) on small intestinal a-glucosidase and postprandial blood glucose levels in rats.
The inhibitory effects of STT on a-glucosidase extracted from small intestines in rats were carried out in vitro. The blood glucose levels were measured after 60 min when sucrose (2 g x kg(-1)) or glucose (2 g x kg(-1)) was administered orally with STT (100 mg x kg(-1)). After treated with STT (100 mg x kg(-1)) for 14 d, the activities of a-glucosidase were determined daily, as well as the postprandial blood glucose levels after oraly administered sucrose (2 g x kg(-1)).
STT at concentrations of 0.1, 1 and 10 mg x mL(-1) reduced significantly the activities of alpha-glucosidase with inhibitory rates of (20.83 +/- 1.66)%, (43.73 +/- 2.39)% and (52.62 +/- 2.69)%, respectively. In facts STT (100 mg x kg(-1)) considerably decreased the blood glucose levels which was 52.61% of that of the control in rats co-administered orally with sucrose (2 g x kg(-1)). However, it showed no such effect on the rats co-administered orally with glucose (2 g x kg(-1)). After orally administered of STT for 14 d, the activity of alpha-glucosidase was significantly reduced (P < 0.05) to (58.17 +/- 3.24)% of that those in control. Meanwhile, The rats were oral administered with sucrose, the increase of postprandial blood glucose levels were (69.50 +/- 4.28)% of that in control 60 min later ( P < 0.05).
It was through inhibiting the activity of a-glucosidase in small intestines that STT significantly retarded the increase in postprandial blood glucose levels in rats.
研究刺蒺藜皂苷（STT）对大鼠小肠α-葡萄糖苷酶及餐后血糖水平的影响。
体外观察STT对大鼠小肠提取的α-葡萄糖苷酶的抑制作用。给予蔗糖（2 g·kg⁻¹）或葡萄糖（2 g·kg⁻¹）的同时灌胃给予STT（100 mg·kg⁻¹），60 min后测定血糖水平。给予STT（100 mg·kg⁻¹）连续14 d，每日测定α-葡萄糖苷酶活性及灌胃蔗糖（2 g·kg⁻¹）后的餐后血糖水平。
浓度为0.1、1和10 mg·mL⁻¹的STT可显著降低α-葡萄糖苷酶活性，抑制率分别为（20.83±1.66）%、（43.73±2.39）%和（52.62±2.69）%。实际上，STT（100 mg·kg⁻¹）可显著降低与蔗糖（2 g·kg⁻¹）同时灌胃的大鼠的血糖水平，为对照组的52.61%。然而，对与葡萄糖（2 g·kg⁻¹）同时灌胃的大鼠无此作用。灌胃STT 14 d后，α-葡萄糖苷酶活性显著降低（P<0.05），为对照组的（58.17±3.24）%。同时，大鼠灌胃蔗糖后，60 min后餐后血糖水平的升高幅度为对照组的（69.50±4.28）%（P<0.05）。
STT通过抑制小肠α-葡萄糖苷酶活性显著延缓大鼠餐后血糖水平的升高。
