Simvastatin attenuates testicular injury induced by torsion-detorsion

Purpose: The lipid lowering agent simvastatin has potent anti-oxidation capacity. We elucidated the potential of simvastatin to attenuate testicular injury induced by testicular torsion-detorsion. We also investigated simvastatin effects on nuclear factor-κB expression. Materials and Methods: We allocated 60 adult male Sprague-Dawley® rats to testicular torsion-detorsion, torsion-detorsion plus simvastatin (1 or 5 mg/kg), sham operation or sham operation plus simvastatin (5 mg/kg). There were 12 rats per group. Simvastatin was administered immediately after detorsion or immediately after sham operation. Testes were harvested 30 minutes and 24 hours after detorsion to facilitate the evaluation of nuclear factor-κB and testicular injury, respectively. Results: Histological findings revealed severe injury in testes of the torsion-detorsion and torsion-detorsion-simvastatin (1 mg/kg) groups while testes in the torsion-detorsion-simvastatin (5 mg/kg) group showed moderate injury. Myeloperoxidase activity, and cytokines, nitric oxide and malondialdehyde in testes in the torsion-detorsion-simvastatin (5 mg/kg) group were significantly lower than in the torsion-detorsion group. Values were comparable in the torsion-detorsion-simvastatin (1 mg/kg) and torsion-detorsion groups. Testicular concentrations of nuclear factor-κB in nuclear extracts and phosphorylated inhibitor-κB in cytosolic extracts in the torsion-detorsion-simvastatin (5 mg/kg) group were significantly lower than in the torsion-detorsion group. Values were comparable in the torsion-detorsion- simvastatin (1 mg/kg) and torsion-detorsion groups. Conclusions: Simvastatin protected testes from torsion-detorsion injury in a dose dependent manner. Mechanisms may involve attenuating nuclear factor-κB activation and decreasing oxidative stress induced by torsion-detorsion.