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 day ), 3- NAC (150 mg kg day ) 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.

Cadmium is known as an oxidative stress‐inducing factor. Silymarin extracted from Silybum marianum is regarded as a potent antioxidant. The present study investigated the preventing effects of silymarin on cadmium chloride‐induced toxicity in terms of testis histopathology and serum testosterone level as well as oxidative stress indicators in mice. In addition, the activities of antioxidant defence enzymes was evaluated. Adult male mice were divided into four groups (n = 6 in each group): (a) control; (b) cadmium chloride; (c) silymarin + cadmium chloride and (d) Silymarin. In this study, cadmium chloride significantly decreased the diameter and wall thickness of the seminiferous tubule, diameter of the spermatogonia nucleus and serum testosterone levels compared to the control group. Furthermore, in mice treated with this pollutant, a significant increase in malondialdehyde was observed while ferric reducing antioxidant power level, and the activity of catalase, superoxide dismutase and glutathione peroxidase were significantly reduced in the testis. In the silymarin + cadmium chloride group, silymarin could significantly reverse the toxic effects of cadmium chloride. The findings of this study showed that silymarin, as a potent antioxidant, can compensate the adverse effects of cadmium chloride on testis histopathology, testosterone level, oxidative stress indicators and antioxidant defence enzymes in mice.

Nonylphenol is the common name for several isomeric substances (4-Nonylphenol, Phenol, p-nonyl-, 4-p-Nonylphenol, 4-nonyl-, para Nonyl) of the general chemical formula C6H4 (OH) C9H19 (Figure 1). Nonylphenol comprise of a phenol that is shifted in the position of para with side chains of disparate degrees of branching (Nielsen, Østergaard, & Thorup, 2000) para-NP or 4-NP is an organic compound of the alkylphenol group. Alkylphenols are a small group of substances known as Xenostrogen (Routledge & Sumpter, 1997). 2 | INTERFEREN CE WITH H UMAN LIFE Generally, nonylphenol is exploited as a naive substance for manufacturing detergents, pesticides, plastics and rubbers, as a supplemental agent or stabiliser of polyvinyl chloride, moreover other acquisitions.