Histopathological study of the combination of metformin and garlic juice for the attenuation of gentamicin renal toxicity in rats

Introduction: Tubular toxicity is one of the most important side effects of aminoglycoside antibiotics, especially gentamicin. Objectives: We histopathologically studied the effect of garlic extract and metformin co-administration, in attenuation of genetamicin induced tubular toxicity in rats. Materials and Methods: In this study seventy rats were divided into seven equal groups and except group 1 (control) were injected 100 mg/kg/day gentamicin (GM) intraperitoneally (i.p.) for 10 days. Other than GM, group III received 20 mg/kg garlic (i.p.), group IV metformin (MF) (100 mg/kg, orally), group V a combination of MF with garlic juice (100 and 20 mg/kg/day, respectively) and group VI a combination of MF and garlic juice (50 and 10 mg/kg/day, respectively) for following 10 days. Group VII received a combination of MF and garlic juice (100 and 20 mg/kg, respectively) along with GM. Animals were sacrificed on the 20th day of the experiment and the kidneys were removed for histological examinations. Results: GM induced nephrotoxicity and garlic or MF alone and a combination of both with high doses (not low doses) significantly abolished the kidney tubular injury induced by GM. In addition, co-administration of GM, MF and garlic (group 7) prevented the GM- induced tissue damage more than the groups in which MF and garlic were injected 10 days post GM administration. Conclusion: Garlic extract and Metformin, alone or in a combination, might be safely used to ameliorate GM induced tubular toxicity.