中药大黄的生物化学研究——蒽醌衍生物对线粒体NADH氧化酶和琥珀酸氧化酶的抑制作用

 实验结果表明:(1)大黄素对线粒体NADH氧化酶和琥珀酸氧化酶有很强的抑制作用,其作用随药物浓度的增大而增强,并呈双曲线型,50％抑制浓度分别为2.5μg/ml和11.5μg/ml。而其它四种蒽醌衍生物如大黄酸、芦荟大黄素、大黄素甲醚和大黄酚对这两种氧化酶的抑制作用不明显,药物浓度为60μg/ml,抑制率均低于20％。(2)拮抗实验表明:核黄素、牛血清蛋白(BSA)能拮抗大黄素对线粒体NADH氧化酶的抑制作用。核黄素(3.3×10~(-4)mol/L)和BSA(1.6mg/ml)对大黄素抑制NADH氧化酶的恢复率分别为50.3％和44.6％,且恢复率随拮抗剂浓度的增加而增加。

BIOCHEMICAL STUDY OF CHINESE RHUBARB INHIBITON OF ANTHRAQUINONE DERIVATIVES ON NADH OXIDASE AND SUCCINATE OXIDASE OF MITOCHONDRION

The effect of anthraquinone derivatives from Chinese rhubarb on NADH oxi-dase and succinate oxidase of mitochondrion have been investigated. The results showed that the activities of NADH oxidase and succinate oxidase were strongly inhibited by emodin. The petcentage inhibition at 20μg/ml concentration were 83.7% and 67.3% respectively and the concentration for 50% inhibition were 2.5μg/ml and 11.5μg/ml, respectively. Other anthraquinone derivatives, namely rhein, aloe-emodin, physcion and chrysophenol, showed no significant effects on both NADH oxidase and succinate oxidase. The observed inhibition at 60μg/ml concentration were below 20%.The inhibition of NADH oxidase by emodin can be reversed by the addition of riboflavin and bovine serum albumin (BSA). The percentage recovery of riboflavin (at 3.3×10-4mol/L) and BSA (at 1.6mg/ml) were 50.3% and 44.6%, respecti-vely.