Protective antioxidant effects of N-acetylcysteine against impairment of spermatogenesis caused by paranonylphenol.

Paranonylphenol (p-NP) is an environmental pollutant that causes oxidative stress. The purpose of this study was to evaluate the protective effect of N-acetylcysteine (NAC) as an antioxidant on sperm parameters and testis in mice after treatment with p-NP. Adult mice were randomly divided into four groups (n = 6, each group) including 1-control, 2- p-NP (250 mg kg-1  day-1 ), 3- NAC (150 mg kg-1  day-1 ) and 4- p-NP + NAC. After 35 days of oral treatment, the mean of spermatogenic index (p < 0.02), sperm count (p < 0.01), daily sperm production (p < 0.01), sperm tail length (p < 0.02), progressive movement (p < 0.04), normal morphology (p < 0.04) and viability (p < 0.01) of spermatozoa and also serum testosterone level (p < 0.04) were significantly reduced in p-NP group when compared to other groups. While the count of the positive TUNEL cells in the seminiferous tubules (p < 0.01) and level of the malondialdehyde (MDA) in testis (p < 0.02) and serum (p < 0.01) significantly increased. In the histopathologic assay in the p-NP group, apoptosis, atrophy, oedema, reduction in sperm density in lumens and vacuoles were observed. The findings of this study indicate that NAC as a potent antioxidant be able to compensate the adverse effects of p-NP in spermatogenesis, testis and levels of testosterone and MDA in the p-NP + NAC group significantly compared to the p-NP group.