title: The cardioprotective effects of a combination of quercetin and α-tocopherol on isoproterenol-induced myocardial infarcted rats.
abstract: The present study aims to evaluate the combined protective effects of quercetin and α-tocopherol on isoproterenol-treated myocardial infarcted rats. Male albino Wistar rats were pretreated with a combination of quercetin (10 mg/kg) and α-tocopherol (10 mg/kg) daily for 14 days. After the pretreatment, rats were injected isoproterenol (100 mg/kg) to induce myocardial infarction. Isoproterenol-treated rats showed increased levels of serum troponins and increased intensities of serum lactate dehydrogenase-1 and -2 isoenzyme bands. Isoproterenol treatment also showed significant decreased levels of antioxidant system and significant increased levels of plasma lipid peroxidation, plasma uric acid, and the heart calcium. Furthermore, isoproterenol-treated rat's electrocardiogram showed elevated ST segments. Combined pretreatment with quercetin and α-tocopherol normalized all the biochemical parameters and minimized the alterations in electrocardiogram. Histopathology of myocardium also confirmed the cardioprotective effects of quercetin and α-tocopherol. In vitro studies confirmed the mechanism of action of quercetin and α-tocopherol. Thus, quercetin and α-tocopherol exhibited cardioprotective effects against isoproterenol-induced cardiotoxicity due to their scavenging free radicals, improving antioxidants and maintaining Ca(2+) levels. Our study also showed that combined pretreatment (quercetin and α-tocopherol) was highly effective than single pretreatment (quercetin or α-tocopherol).
authors.affiliation: Department of Biochemistry and Biotechnology, Annamalai University, Annamalai Nagar 608 002, Tamil Nadu, India.
authors.forename: V R
authors.initials: VR
authors.lastname: Punithavathi
authors.forename: P
authors.initials: P
authors.lastname: Stanely Mainzen Prince
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001205:Ascorbic Acid / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002316:Cardiotonic Agents / Q000494:pharmacology*; D004359:Drug Therapy, Combination; D004562:Electrocardiography / Q000379:methods; D016166:Free Radical Scavengers / Q000494:pharmacology; D005978:Glutathione / Q000187:drug effects / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000187:drug effects / Q000378:metabolism; D005980:Glutathione Reductase / Q000187:drug effects / Q000378:metabolism; D007527:Isoenzymes / Q000187:drug effects / Q000378:metabolism; D007545:Isoproterenol; D007770:L-Lactate Dehydrogenase / Q000187:drug effects / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D009203:Myocardial Infarction / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D009206:Myocardium / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D011794:Quercetin / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000187:drug effects / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D019210:Troponin I / Q000097:blood / Q000187:drug effects / Q000378:metabolism; D020107:Troponin T / Q000097:blood / Q000187:drug effects / Q000378:metabolism; D014527:Uric Acid / Q000097:blood / Q000378:metabolism; D024502:alpha-Tocopherol / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D002316:Cardiotonic Agents; D016166:Free Radical Scavengers; D007527:Isoenzymes; D017392:Thiobarbituric Acid Reactive Substances; D019210:Troponin I; D020107:Troponin T; D014527:Uric Acid; D011794:Quercetin; D007770:L-Lactate Dehydrogenase; C409676:lactate dehydrogenase 2; C409667:lactate dehydrogenase 1; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005978:Glutathione; D024502:alpha-Tocopherol; D007545:Isoproterenol; D001205:Ascorbic Acid; D002118:Calcium