Protective effect of N-acetyl cysteine and/or pro vitamin A against monosodium glutamate-induced cardiopathy in rats

Abstract

In the present study the prophylactic effects of the antioxidants, β-carotene and/or N-acetyl cysteine (NAC) in ameliorating the metabolic abnormalities and oxidative damage induced cardiopathy under the effect of the flavor enhancers, monosodium glutamate (MSG) toxicity were studied. Animals were divided into 5 groups; G1: normal control, G2: MSG-treated group, Gs 3,4 and 5: animals pretreated with either NAC or β-carotene or their combination prior MSG administration, respectively. The present results revealed that, chronic administration of MSG caused metabolic dysfunction characterized by significant increases in the levels of serum glucose, total lipids, triglycerides (TG), total cholesterol (TCh) and Low Density Lipoprotein (LDL) and a decrease in the high density lipoprotein (HDL), parameters have important role in MSG induced cardiovascular disorders. The adverse effects of MSG may be related to an imbalance between the oxidant and antioxidant systems. This was indicated by marked increased levels of serum nitric oxide (NO) accompanied by pronounced increased level of thiobarbituric acid reactive substances (TBARS, marker of lipid peroxidation) and decreased levels of the antioxidants, L-ascorbic acid, glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) in cardiac tissue versus normal animals. Significant inhibition in cardiac Na+/K+ ATPase with increase in serum activities of creatine phophokinase (CPK) and aspartate aminotransferase (AST) were also observed in MSG treated animals as biomarker enzymes of cardiac tissue damage. This result was supported by myocardial infarction (necrotic lesion) observed by histopathological examination. Administration of either β-carotene or NAC prior MSG injection significantly modulated the alteration in most of the previously mentioned parameters to near their normal levels. Administration of synergistic combination of the these antioxidants showed the most significant effect as it has the ability to restore all of the studied parameters to their normal levels. The biochemical results were supported by the improvement in histological architecture of heart tissue, implicating that these antioxidants either alone or their combination may protect heart from the harmful effects of cardio-toxic agents. © 2009 Academic Journals Inc.