Asian Journal of Biochemistry, Genetics and Molecular Biology

Obesity is a global health concern linked to oxidative stress and kidney dysfunction. Citrus sinensis (sweet orange) peels, typically a waste product, are rich in bioactive compounds with antioxidant potential. This study evaluated the protective and antioxidant effects of sweet orange peel extract in obese Wistar rats. Obesity was induced using oral dexamethasone for two weeks, followed by a 21-day treatment with ethanolic peel extract at varying doses. Rats were divided into six groups (n=5), and kidney function was assessed through serum levels of urea, creatinine, sodium, bicarbonate, and chloride. Antioxidant status was evaluated using markers such as malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT). Additionally, in vitro assays assessed the extract’s scavenging ability for superoxide, hydrogen peroxide, and nitric oxide radicals. Obese rats showed elevated urea, creatinine, sodium, and MDA levels, indicating kidney impairment and increased oxidative stress (p<0.05), alongside reduced antioxidant enzyme activity. Treatment with the peel extract resulted in dose-dependent improvements: reduced urea, creatinine, and sodium levels, particularly at medium (200 mg/kg) and high doses, and improved antioxidant enzyme activity. Bicarbonate levels were lowest in the medium-dose group, while chloride levels were highest in the high-dose group. In vitro, the extract demonstrated strong radical scavenging activity, confirming its antioxidant potential. These findings suggest that C. sinensis peel extract mitigates oxidative stress and kidney dysfunction in obesity, supporting its potential as a nutraceutical. Further studies are recommended to investigate its active components and mechanisms of action.