beta-carotene and Cardiomyopathies

Chronic heart failure (CHF) seems to be associated with increased oxidative stress. However, the hypothesis that antioxidant nutrients may contribute to the clinical severity of the disease has never been investigated.. To examine whether antioxidant nutrients influence the exercise capacity and left ventricular function in patients with CHF.. Dietary intake and blood levels of major antioxidant nutrients were evaluated in 21 consecutive CHF patients and in healthy age- and sex-matched controls. Two indexes of the severity of CHF, peak exercise oxygen consumption (peak VO2) and left ventricular ejection fraction (LVEF), were measured and their relations with antioxidants were analysed.. Whereas plasma alpha-tocopherol and retinol were in the normal range, vitamin C (P=0.005) and beta-carotene (P=0.01) were lower in CHF. However, there was no significant association between vitamins and either peak VO2 or LVEF. Dietary intake (P<0.05) and blood levels of selenium (P<0.0005) were lower in CHF. Peak VO2 (but not LVEF) was strongly correlated with blood selenium: r=0.76 by univariate analysis (polynomial regression) and r=0.87 (P<0.0005) after adjustment for age, sex and LVEF.. Antioxidant defences are altered in patients with CHF. Selenium may play a role in the clinical severity of the disease, rather than in the degree of left ventricular dysfunction. Further studies are warranted to confirm the data in a large sample size and to investigate the mechanisms by which selenium and other antioxidant nutrients are involved in CHF.

Topics: Adult; Aged; Antioxidants; Ascorbic Acid; beta Carotene; Cardiomyopathies; Chronic Disease; Feeding Behavior; Female; Heart Failure; Humans; Male; Middle Aged; Oxidative Stress; Selenium; Ventricular Function, Left

To study the effects of beta-carotene (Car) reducing the cardiotoxicity induced by doxorubicin (Dox).. The pathological changes of rat myocardium were observed with photomicroscopy. The malondialdehyde (MDA) value of rat heart was measured with thiobarbituric acid method. The pyrogallol autoxidation method was used for determination of superoxide dismutase (SOD) activity. The activities of glutathione peroxidase (GSH-Px) were quantitatived with DTNB method. Electron spin resonance (ESR) technique was used to measure the level of the semiquinone free radicals.. Car 10 or 30 mg.kg-1.d-1 i.g. reduced the cardiotoxicity induced by Dox, diminished the myocardial MDA production (P < 0.01), and protected the activities of SOD and GSH-Px. ESR revealed 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%, respectively.. Car, with abilities of anti-lipid peroxidation and scavenging semiquinone free radicals, possessed effects of reducing Dox-induced cardiotoxicity.

Topics: Animals; Antioxidants; beta Carotene; Cardiomyopathies; Doxorubicin; Female; Free Radical Scavengers; Glutathione Peroxidase; Male; Malondialdehyde; Myocardium; Rats; Superoxide Dismutase