Renal Histology and Function in Gentamicin-Induced Acute Kidney Injury (Aki) in Rats Given Natural Cocoa

Abstract

Background: Gentamicin (GM) administration generates reactive oxygen species that have long been identified with nephrotoxicity. Cocoa flavanols are powerful antioxidants that have free radical scavenging capacity in reactive oxygen species (ROS) -mediated inflammatory processes such as from GM usage. Aim: This study investigated whether regular ingestion of natural cocoa would protect renal structure and function in rats with GM-induced acute kidney injury (AKI). Methodology: Thirty-two male Sprague Dawley rats of 5 groups (G1, G2, G3, G4, and G5) with 7 animals each in G1 to G4 and 4 in G5 were used for the study. Rats in G1, G2 and G5 groups were fed on 2 % w/v of natural cocoa suspension (NCS) for 6 weeks in addition to their rat chow. Rats in G3 and G4 were not given cocoa but were also fed on rat chow. At the end of 6 weeks, rats in G1 were taken off NCS and given 100 mg/kg GM intraperitoneally (i.p) for 5 days. G2 rats continued NCS intake for another 5 days with 100 mg/kg GM i.p. G3 and G5 rats received 100 mg/kg of normal saline (0.9 % N/S) as placebo whiles G4 rats were injected with 100 mg/kg of GM i.p. Body weights, serum creatinine (SCr) and blood urea nitrogen (BUN) were measured at weeks 0, 6 and 7 for all groups. Histomorphometric assessment was conducted on volumes of renal glomeruli and proximal convoluted tubular (PCT) cells as a quantitative measure of altered renal morphology. Results: GM treated rats had elevated SCr and BUN (ANOVA, p = 0.032) levels and decreased weight. Stereologic assessments also showed reduced volumes of glomeruli (Kruskal Wallis, p = 0.006) and PCTs in GM treated groups (ANOVA, p = 0.000) compared to control (G3) and regularly fed cocoa groups (G2). Conclusion: GM-induced renal structural and functional damage was minimized in NCS fed G2 rats compared to G4 rats