Effect of vitamin E alone and in combination with lycopene on biochemical and histopathological alterations in isoproterenol-induced myocardial infarction in rats

BACKGROUND: The present study has been designed to evaluate the combined cardioprotective effect of vitamin E and lycopene on biochemical and histopathological alteration in isoproterenol-induced myocardial infarction in rats. MATERIALS AND METHODS: Adult male albino rats of Wistar strain were treated with isoproterenol (200 mg/kg, s.c.) for 2 days at an interval of 24 h to develop myocardial infarction. Vitamin E (100 mg/kg/day, p.o.) and lycopene (10 mg/kg/day, p.o.) were administered alone and in combination for 30 days. Change in body weight and organ weight were monitored. Levels of serum marker enzymes (AST, ALT, LDH and CK-MB), lipid peroxidation, endogenous antioxidants (GSH, GPX, GST, SOD and CAT), membrane bound enzymes (Na(+)/K(+) ATPases, Mg(2+) ATPases and Ca(2+) ATPases) were evaluated. LDH isoenzyme separation was carried out using gel electrophoresis. Histopathology of heart tissue was performed. RESULTS: Induction of rats with isoproterenol resulted in a significant elevation in organ weight, lipid peroxidation, serum marker enzymes (AST, ALT, CK-MB and LDH), and Ca( 2+) ATPases, whereas it caused a significant (P < 0.001) decrease in body weight, activities of endogenous antioxidants (GSH, GP(x), GST, SOD and CAT), Na(+)/K(+) and Mg(2+) ATPases. ISO treated rats showed high intensity band of LDH1-LDH2 isoenzymes. Treatment with the combination of Vitamin E and lycopene for 30 days significantly attenuated these changes as compared to the individual treatment and ISO treated groups. Histopathological observations were also in correlation with the biochemical parameters. CONCLUSION: These findings indicate the synergistic cardioprotective effects of vitamin E and lycopene during ISO-induced myocardial infarction in rats.