Protective Effects of Ethanol Extract of Azanza garckeana Fruit on Gentamicin-induced Nephrotoxicity in Wistar Rats

Abstract

Gentamicin remains an important aminoglycoside antibiotic, but its therapeutic application is limited by nephrotoxicity, which is associated with oxidative stress and structural injury to renal tissues. This study investigated the protective effects of ethanol fruit extract of Azanza garckeana against gentamicin-induced renal dysfunction in Wistar rats. Thirty Wistar rats weighing 150–200 g was randomly assigned to six groups (n = 5). Group 1 served as the untreated control, while Group 2 received gentamicin without treatment. Groups 3–5 received gentamicin followed by vitamin E (10 mg/kg), 100 mg/kg A. garckeana extract, and 200 mg/kg A. garckeana extract, respectively, while Group 6 received a combination of 100 mg/kg extract and vitamin E (10 mg/kg). The ethanol fruit extract was prepared by batch extraction using absolute ethanol, and quantitative phytochemical analysis was performed spectrophotometrically. Kidney function biomarkers, oxidative stress indices, liver enzymes, kidney and liver histology were assessed using standard methods. The extract contained several flavonoids, isoflavones and phenolic acids, with daidzin (69.03 mg/mL), piperic acid (21.55 mg/mL), catechin (11.00 mg/mL), butein (8.41 mg/mL), kaempferol (8.30 mg/mL) and naringenin (7.08 mg/mL) among the prominent constituents. Gentamicin exposure was associated with alterations in renal biochemical indices, depletion of glutathione, catalase and superoxide dismutase activities, and increased malondialdehyde. Treatment with A. garckeana modified several of these changes, while histological examination demonstrated severe renal damage in the untreated gentamicin group and partial structural preservation in the extract-treated groups. The 200 mg/kg extract group generally showed better renal architectural preservation than the 100 mg/kg group. The findings indicate that ethanol fruit extract of A. garckeana was associated with partial renal structural preservation. Further studies are required to establish the active constituents, mechanisms of action and safety profile of the extract.