Effects of curcumin on gentamicin-induced experimental testicular injury in rats

The aim of this study was to determine the role of oxidative stress and histopathologic changes caused by gentamicin on testis and to investigate whether curcumin, an antioxidant, has protective effects. In the study, 24 male Sprague Dawley rats were divided into 4 groups. Control group was treated with 0.5 ml Dimethyl Sulfoxide (70%) daily for 7 days starting from the 1st day of the experiment. Gentamicin group was administered intraperitoneal gentamicin at a dose of 100 mg/kg daily for 7 days starting from the 1st day of the experiment. Curcumin group received curcumin dissolved in 0.5 ml Dimethyl Sulfoxide (70%) at a daily dose of 10 mg/kg for 7 days starting from the 1st day of the experiment. Gentamicin+Curcumin group received curcumin dissolved in 0.5 ml Dimethyl Sulfoxide (70%) at a dose of 10 mg/kg intraperitoneally and gentamicin at a dose of 100 mg/kg intraperitoneally for 7 days starting from day 1 of the experiment. The subjects were weighed on the 1st and 8th day of the experiment. On the 8th day of the experiment, the subjects were decapitated under anesthesia. Left testis was used for histological evaluations and right testis was used for biochemical evaluations. The left epididymis was evaluated for total sperm count, vitality, motility and morphological analysis. The right epididymis was used for histologic evaluations. The right epididymis tissues were stained with Hematoxylin & Eosin and the left testis tissues were stained with Hematoxylin & Eosin, Masson Trichrome, Periodic Acid-Schiff and terminal deoxynucleotidyl transferase (TDT)- deoxyuridine triphosphate (dUTP) nick end labeling assay (TUNEL) stains. Body and testicular mass analyses were obtained from the weighing results. Absolute seminiferous tubule volume, total seminiferous tubule length, total seminiferous tubule surface area total Sertoli cell count, Sertoli cell count per gram, total Leydig cell count, Leydig cell count per unit volume, total round spermatid count, daily sperm production, daily sperm production per gram, seminiferous tubule diameter, germinal epithelial thickness, germinal epithelial thickness / seminiferous tubule diameter, Modified Johnsen scoring, germinal epithelial separation parameters were examined. In Masson Trichrome staining examinations, connective tissue increase in the interstitial area, edema in the interstitial area, and tunica albuginea thickness were examined. Basement membrane damage scoring was performed in Periodic Acid- Schiff staining. Apoptotic index of the groups was calculated in TUNEL staining findings. Malondialdehyde, superoxide dismutase, glutathione peroxidase, glutathione, 8-OHdG, TNF-⍺, myeloperoxidase, caspase-3, total oxidative status, total antioxidant status and oxidative stress index levels were analyzed in testicular tissue. The results showed that gentamicin caused physiologic, histologic and biochemical damage in the testis, while curcumin given as an antioxidant agent corrected almost all of the impaired parameters, often partially and sometimes almost completely.