Punica granatum improves renal function in gentamicin-induced nephropathy in rats via attenuation of oxidative stress

BACKGROUND: Gentamicin is widely used as an antibiotic for the treatment of gram negative infections. Evidences indicates that oxidative stress is involved in gentamicin-induced nephrotoxicity. In Ayurvedic medicine, Punica granatum Linn. is considered as 'a pharmacy unto itself”. It has been claimed in traditional literature, to treat various kidney ailments due to its antioxidant potential. OBJECTIVE: To explore the possible mechanism of action of methanolic extract of P.granatum leaves (MPGL) in exerting a protective effect on gentamicin-induced nephropathy. MATERIAL AND METHODS: Animals were administered with gentamicin (80 mg/kg/day i.m.) and simultaneously with MPGL (100, 200 and 400 mg/kg p.o.) or metformin (100 mg/kg p.o.) for 8 days. A satellite group was employed in order to check for reversibility of nephrotoxic effects post discontinuation of gentamicin administration. At the end of the study, all the rats were sacrificed and serum–urine parameters were investigated. Antioxidant enzymes and tumor necrosis factor alpha (TNF-α) levels were determined in the kidney tissues along with histopathological examination of kidneys. RESULTS: Increase in serum creatinine, urea, TNF-α, lipid peroxidation along with fall in the antioxidant enzymes activity and degeneration of tubules, arterioles as revealed by histopathological examination confirmed the manifestation of nephrotoxicity caused due to gentamicin. Simultaneous administration of MPGL and gentamicin protected kidneys against nephrotoxic effects of gentamicin as evidenced from normalization of renal function parameters and amelioration of histopathological changes. CONCLUSION: Data suggests that MPGL attenuated oxidative stress associated renal injury by preserving antioxidant enzymes, reducing lipid peroxidation and inhibiting inflammatory mediators such as TNF-α.