EFFECTS OF BETA-CAROTENE ON DOXORUBICIN-INDUCED CARDIOTOXICITY IN RATS

AIM: To study the effects of beta-carotene (Car) reducing the cardioto xicity induced by doxorubicin (Dox). METHODS: The pathological changes of rat myocardium were observed with photomicroscopy. The malondialde hyde (MDA) value of rat heart was measured with thiobarbituric acid me thod. The pyrogallol autoxidation method was used for determination of superoxide dismutase (SOD) activity. The activities of glutathione pe roxidase (GSH-Px) were quantitatived with DTNB method. Electron spin r esonance (ESR) technique was used to measure the level of the semiquin one free radicals. RESULTS: Car 10 or 30 mg . kg(-1). d(-1) is reduced the cardiotoxicity induced by Dox, diminished the myocardial MDA prod uct (P < 0.01), and protected the activities of SOD and GSH-Px. ESR re vealed that Car scavenged semiquinone free radicals induced by Dox in vitro. The inhibitory rates of semiquinone free radicals formation by Car 0.02, 0.1, and 1.0 mmol . L(-1) were 47.7 %, 76.6 %, and 82.5 %, r espectively. CONCLUSIONS: Car, with abilities of anti-lipid peroxidati on and scavenging semiquinone free radicals, possessed effects of redu cing Dox-induced cardiotoxicity.