玄参中环烯醚萜Epibueropyridinium A对醛糖还原酶的抑制作用

Inhibitory effect of Epibueropyridium A extracted from scrophularia ningpoensis on aldose reductase

目的:研究Epibueropyridium A对醛糖还原酶的抑制作用。方法:醛糖还原酶通过硫酸铵分级沉淀从牛眼晶状体中提取,在含有DL-甘油醛、醛糖还原酶、NADPH的反应体系中,加入一定浓度的Epibueropyridium A,通过340 nm处光密度的变化来反映Epibueropyridium A对酶活性的抑制作用。阳性对照为依帕司他,采用双倒数作图的方法确定抑制类型,二次作图法求Ki,以抑制剂浓度对抑制率作图求IC50。结果:Epibueropyridium A能显著抑制醛糖还原酶的活性,为竞争性抑制,其半数抑制剂量IC50为4.2μg/ml,Ki值为4.88μg/ml。结论:Epibueropyridium A是醛糖还原酶的竞争性抑制剂。

Objective： To investigate the inhibitory effect of Epibueropyridinium A on aldose reductase. Methods： Aldose reductase was extracted from cattle crystalline lens. Besides Epibueropyridinium A, the reactive system also contained DL-glyceraldehyde, aldose reductase, and NADPH. The activity changes of aldose reductase were detected at 340 nm. Epalrestat was taken as the positive control. The inhibitory type, Ki and IC50 were determined by double reciprocal plot, quadratic drawing, and drawing of inhibitor＇s concentration to inhibitory ratio, respectively. Results： Epibueropyridinium A significantly inhibited the activity of aldose reductase in a competitive manner, with IC50 being 4.2 μg/ml and Ki being 4.88μg/ml. Conclusion.. Epibueropyridinium A is competitive inhibitor of aldose reductase.