Effect of selenium and pentoxifylline on expression of CATSPER1 and 2 genes and FSH/LH levels in treated mice by dexamethasone

Dexamethasone has deleterious effects on male fertility and sperm parameters. In this study, the effect of dexamethasone on expression of CATSPER1 and 2 genes was investigated. These two genes play an important role in sperm motility. Selenium and pentoxifylline were subsequently used to protect testis tissue against the destructive effects of dexamethasone. Each group received one of the following treatments for 7 days: dexamethasone (7 mg/kg), pentoxifylline (200 mg/kg), selenium (0.3 mg/kg), dexamethasone + pentoxifylline or selenium + dexamethasone. Animals in the control group received a normal saline injection. The expression of CATSPER1 and 2 genes was analysed by real-time PCR and serum levels of FSH and LH were determined with the enzyme-linked immunosorbent assay method. Based on the results, dexamethasone decreases not only CATSPER1 and 2 gene expression but also serum levels of LH (p <= 0.05); however, it has no effect on FSH (p > 0.05). Treating with selenium significantly increased the gene expression of both CATSPER1 and 2 (p <= 0.05), while pentoxifylline enhanced only CATSPER2 gene expression (p <= 0.05). These two antioxidants were shown to increase serum levels of LH (p <= 0.05). Our data suggest that selenium is more effective than pentoxifylline in overcoming adverse effects of dexamethasone on male fertility.