modulatory effect of pioglitazone on sperm parameters and oxidative stress, apoptotic and inflammatory biomarkers in testes of streptozotocin-induced diabetic rats

Background and aims: diabetes mellitus causes testicular damage by increasing oxidative stress and inflammation. in the present study, modulation of oxidative stress by pioglitazone, a synthetic ligand of peroxisome proliferator-activated receptor-γ, was examined in testis of streptozotocin-induced diabetic rats. materials and methods: diabetes was induced by a single dose of streptozotocin (65 mg/kg, i.p.) injection in male wistar rats. 32 adult male rats were divided into four groups (n=8): control, diabetic, diabetic pioglitazone (1 mg/kg/day) and diabetic pioglitazone (10 mg/kg/day). rats were treated with pioglitazone for 5 weeks. serum testosterone levels were estimated. reproductive damage was evaluated by sperm parameters (viability, motility, morphology and count). oxidative stress markers were evaluated in testicular homogenate. pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-1β) levels, expressions of inflammatory (inducible nitric oxide synthase and nuclear factor-κ b) and apoptotic markers (caspase-3) in testicular tissue were performed by enzyme-linked immunosorbent assay and western blot. results: pioglitazone treatment significantly increased sperm parameters (p<0.05). no significant decrease in serum level of testosterone was observed in the pioglitazone treated mice (p>0.05). aside from reducing the elevated tissue nitric oxide and malondialdehyde levels, pioglitazone increased the reduced superoxide dismutase, catalas and total antioxidant capacity in testes compared to diabetic rats (p<0.05). pioglitazone reduced testicular inflammation by decreasing the expressions of inducible nitric oxide synthase, nuclear factor-κb and pro-inflammatory cytokines levels and inhibited cell death by decreasing the expressions of caspase-3 (p<0.05). conclusions: pioglitazone attenuated testicular damage in diabetic rats by decreasing oxidative stress, testicular inflammation and testicular damage.