A Combination of Melatonin and Alpha Lipoic Acid Abrogates Chromium-Induced Cardiac Oxidative Damage

This study was designed to examine the cardioprotective effects of a combination of melatonin (10 mg / Kg BW) + alpha lipoic acid (25 mg / Kg BW) [M + A] against cardiac oxyradical alterations due to chromium toxicity in rats. Apart from monitoring electrocardiograph parameters, diagnostic cardiac marker enzymes, myocardial antioxidative parameters, trace element alterations and degree of metallothionein (MT) induction were also assessed. Administration of hexavalent chromium as Cr (VI) oxide (7.06 mg/kg for 15 days) to female Wistar rats induced marked alterations in ECG - patterns, significant increases in serum levels of creatine phosphokinase–MB (CPK-MB), lactate dehydrogenase (LDH) and cardiac troponin I (cTnI). Moreover, the level of myocardial thiobarbituric acid-reactive substances was significantly increased while, reduced glutathione content and activities of antioxidant enzymes [SOD, CAT, GPx, GR and GST] were significantly decreased. Administration of M + A significantly prevented leakage of marker enzymes of cardiac damage, changes in cardiac free radical generation, antioxidant status, histochemical changes and, augmented the degree of cysteine rich antioxidant and metal chelating protein, metallothionein (MT) induction,. These findings indicate that M + A exert an additive cardio protective effect on chromium – induced cardiac oxidative damage in rats.