title: Attenuation of oxidative stress and cardioprotective effects of zinc supplementation in experimental diabetic rats.
abstract: Oxidative stress plays a major role in the pathogenesis of diabetes mellitus, which further exacerbates damage of cardiac, hepatic and other tissues. We have recently reported that Zn supplementation beneficially modulates hyperglycaemia and hypoinsulinaemia, with attendant reduction of associated metabolic abnormalities in diabetic rats. The present study assessed the potential of Zn supplementation in modulating oxidative stress and cardioprotective effects in diabetic rats. Diabetes was induced in Wistar rats with streptozotocin, and groups of diabetic rats were treated with 5- and 10-fold dietary Zn interventions (0·19 and 0·38 g Zn/kg diet) for 6 weeks. The markers of oxidative stress, antioxidant enzyme activities and concentrations of antioxidant molecules, lipid profile, and expressions of fibrosis and pro-apoptotic factors in the cardiac tissue were particularly assessed. Supplemental Zn showed significant attenuation of diabetes-induced oxidative stress in terms of altered antioxidant enzyme activities and increased the concentrations of antioxidant molecules. Hypercholesterolaemia and hyperlipidaemia were also significantly countered by Zn supplementation. Along with attenuated oxidative stress, Zn supplementation also showed significant cardioprotective effects by altering the mRNA expressions of fibrosis and pro-apoptotic factors (by >50 %). The expression of lipid oxidative marker 4-hydroxy-2-nonenal (4-HNE) protein in cardiac tissue of diabetic animals was rectified (68 %) by Zn supplementation. Elevated cardiac and hepatic markers in circulation and pathological abnormalities in cardiac and hepatic tissue architecture of diabetic animals were ameliorated by dietary Zn intervention. The present study indicates that Zn supplementation can attenuate diabetes-induced oxidative stress in circulation as well as in cardiac and hepatic tissues.
authors.affiliation: Department of Biochemistry and Nutrition,Central Food Technological Research Institute (CSIR),Mysore 570 020,India.
authors.forename: Susmita
authors.initials: S
authors.lastname: Barman
authors.affiliation: Department of Biochemistry and Nutrition,Central Food Technological Research Institute (CSIR),Mysore 570 020,India.
authors.forename: Krishnapura
authors.initials: K
authors.lastname: Srinivasan
mesh_terms: D000447:Aldehydes / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control; D002374:Catalase / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D019587:Dietary Supplements; D005355:Fibrosis; D005978:Glutathione / Q000378:metabolism; D006321:Heart / Q000187:drug effects*; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects*; D012333:RNA, Messenger / Q000378:metabolism; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism; D014131:Trace Elements / Q000494:pharmacology / Q000627:therapeutic use; D015032:Zinc / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D000447:Aldehydes; D000975:Antioxidants; D015415:Biomarkers; D012333:RNA, Messenger; D014131:Trace Elements; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione; D015032:Zinc; C027576:4-hydroxy-2-nonenal
keywords:  4-HNE 4-hydroxy-2-nonenal;  Bax BCL2 associated X protein;  Bcl-2 B-cell lymphoma 2;  CAT catalase;  CK-MB creatine phosphokinase–MB;  GPx glutathione peroxidase;  GR glutathione reductase;  GST glutathione-S-transferase;  LPO lipid peroxidation;  PAS periodic acid Schiff;  PC protein carbonyl;  ROS reactive oxygen species;  SOD superoxide dismutase; Antioxidant enzymes; Cardioprotective effects; Diabetes mellitus; Fibrosis and apoptosis markers; Oxidative stress; Zinc supplementation