Effects of beta-carotene on oxidative stress in normal and diabetic rats.
Increasing interest in the role of oxidative stress and beta-carotene in disease and prevention led us to examine the results of beta-carotene's administration in diabetic rats, a model for high-oxidative stress. In this experiment, amounts of lipid peroxidation, glutathione, and glutathione disulfide, and activity levels of catalase, glutathione peroxidase, glutathione reductase, superoxide dismutase, and gamma-glutamyl transpeptidase were measured in the liver, kidney, and heart of Sprague-Dawley rats with streptozotocin-induced diabetes, and after treatment with 10 mg/kg/day of beta-carotene for 14 days. Beta-carotene treatment resulted in the reversal of the diabetes-induced increase in hepatic and cardiac catalase activity, the decreased levels of glutathione disulfide in the heart, and the increased cardiac and renal levels of lipid peroxidation. Treatment with beta-carotene exacerbated the increased glutathione peroxidase activity in the heart and the decreased catalase activity in the kidneys. In contrast to reduced hepatic glutathione levels in untreated diabetic rats, beta-carotene treatment increased glutathione levels in diabetic rats. Increased hepatic gamma-glutamyl transpeptidase activity in diabetic rats was not reduced by treatment. Thus, beta-carotene therapy for 14 days prevented/reversed some, but not all, diabetes-induced changes in oxidative stress parameters.
Maritim
Alice
A
Faculty of Health Sciences, Moi University, Eldoret, Kenya.
Dene
Barbara A
BA
Sanders
Ruth A
RA
Watkins
John B
JB
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D005260:Female; D007668:Kidney / Q000187:drug effects / Q000201:enzymology; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D019207:beta Carotene / Q000494:pharmacology*
D019207:beta Carotene