Effects of Permethrin on Oxidative Stress, Apoptosis, Mitochondrial Ultrastructure in Rat Testes

Objective: The aim was to investigate the dose-dependent effects of PER on testes. Material & Methods: Male Wistar albino rats (n=28; 2 months old; 250–400 g) were randomly divided into four groups (n = 7 in each group): control (sham), low (20 mg/kg/day), medium (40 mg/kg/day), and high (75 mg/kg/day) dose PER groups. PER was administered orally for 14 days. Testicular morphology was evaluated by hematoxylin-eosin staining. Immunohistochemically, superoxide dismutase 1 (SOD1), catalase (CAT), and active caspase-3 expression were examined. Ultrastructural intracellular alterations were examined using transmission electron microscopy. Results: Light microscopy showed that the general structure of the seminiferous tubules was largely preserved. In contrast, edema in the interstitial space and decreased cell density were observed in the medium and high dose groups. SOD1 expression was significantly increased in the high dose group, while CAT expression was significantly decreased in the medium and high dose groups. Active caspase-3 staining was dose-dependent and significantly increased in both the medium and high dose groups. Electron microscopic examination revealed mitochondrial swelling and cristae disruption, chromatin condensation, cytoplasmic vacuoles, and endoplasmic reticulum enlargement. Conclusion: The findings indicate that PER disrupts the antioxidant defense balance and increases apoptosis in testicular tissue. Mitochondrial changes may be important early cellular findings in PER-induced testicular damage.