Cardioprotective activity on oryzanol in insulin resistance in rats

Sravani Banka; Reddy Kumari C; Saleem Mohammed

doi:10.37022/jiaps.v10i3.779

Sravani Banka Assistant Professor, Aadya College of Pharmacy, Chitradurga, Bengaluru.
Reddy Kumari .C Assistant Professor, Department of Pharmacology, Gautam college of Pharmacy, Bengaluru.
Mohammed Saleem Assistant Professor, Department of Pharmacology, Gautam college of Pharmacy, Bengaluru.

DOI https://doi.org/10.37022/jiaps.v10i3.779

Abstract

Cardiovascular diseases (CVDs) are a leading cause of morbidity and mortality worldwide, with insulin resistance (IR) being a major metabolic risk factor. This study investigated the cardioprotective potential of γ-oryzanol in dexamethasone-induced insulin-resistant rats subjected to isoproterenol-induced myocardial toxicity. Forty-two male Wistar rats were divided into seven groups, including normal control, insulin-resistant control, cardiotoxic control, combined insulin resistance and cardiotoxicity, oryzanol alone, oryzanol-treated, and standard drug (propranolol) groups. Serum biochemical parameters, lipid profile, cardiac injury markers (SGOT, SGPT, LDH), and myocardial oxidative stress markers (TBARS, GSH, SOD, CAT) were assessed. Histopathological analysis of heart tissue was performed to evaluate structural alterations. Isoproterenol administration significantly increased TBARS, SGOT, SGPT, LDL, VLDL, and triglyceride levels while reducing GSH, SOD, and CAT, indicating oxidative stress and cardiotoxicity. Treatment with γ-oryzanol significantly restored antioxidant enzyme levels, reduced lipid peroxidation, improved serum lipid profile, and normalized cardiac biomarkers. Histopathology revealed well-preserved myocardial architecture in oryzanol-treated rats compared to isoproterenol-treated controls, confirming its cardioprotective effect. These findings suggest that γ-oryzanol exerts significant cardioprotective activity in insulin-resistant rats through antioxidant, lipid-lowering, and myocardial protective mechanisms. Thus, γ-oryzanol may represent a potential nutritional therapeutic agent for preventing or mitigating cardiovascular complications associated with metabolic disorders.

Keywords: γ-Oryzanol, Cardioprotection, Insulin Resistance, Oxidative Stress, Lipid Profile, Isoproterenol

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