Protective effects of l-arginine against testosterone synthesis decreased by T-2 toxin in mouse Leydig cells.

The testosterone levels decreased by T-2 toxin in mouse Leydig cells were reported previously. It is not known, however, whether l-arginine improves the situation and what's the mechanism. Leydig cells were isolated and cultured with control, 10 nM T-2 toxin, 0.25, 0.5 or 1.0 mM l-arginine, and 10 nM T-2 toxin supplemented with 0.25, 0.5 or 1.0 mM l-arginine for 24 h. Cells and supernatants were collected to detect the mRNA expression and activities of P450scc (cholesterol side-chain cleavage enzyme), 3ß-HSD-1 (3ß-hydroxysteroid dehydrogenase/isomerase-1) and StAR (steroidogenic acute regulatory protein). Results revealed that l-arginine increased the testosterone levels declined by T-2 toxin and up-regulated the activities and mRNA expression of P450scc, 3ß-HSD-1 and StAR down-regulated by T-2 toxin in Leydig cells. Therefore, we concluded that l-arginine ameliorated the testosterone levels decreased by T-2 Toxin via regulating the mRNA expression and activities of P450scc, 3ß-HSD-1 and StAR in mouse Leydig cells.

l-arginine protects against T-2 toxin-induced male reproductive impairments in mice.

l-arginine is beneficial for reproductive health; however, whether l-arginine may confer protection against T-2 toxin-induced reproductive impairment is not known. To address this, we used a mice model treated with T-2 toxin to investigate protective effects of l-arginine. Experimentally, we pre-treated mice with designed diet of l-arginine supplementation prior to the T-2 toxin-injected intraperitoneally exposure and then assessed semen quality, fertility and serum testosterone concentration. The results showed that l-arginine improved semen quality (e.g., live spermatozoa, abnormal spermatozoa, and acrosomal integrity of spermatozoa), testicular and cauda epididymal sperm counts, efficiency of sperm production and serum testosterone concentration in mice treated with T-2 toxin. In addition, l-arginine could increase pregnancy rate and decrease fetal resorption rate in females mated with T-2 toxin exposed males. Collectively, these findings suggest that dietary l-arginine supplementation may protect male reproductive impairments in mice treated with T-2 toxin through improving semen quality and serum testosterone levels.

Toxic effects of T-2 toxin on reproductive system in male mice.

The present study was conducted to evaluate the effects of T-2 toxin on semen quality, fertility and serum testosterone concentration in mice. Adult male mice were mated with sexually mature untreated female mice after being exposed to intraperitoneal injection of T-2 toxin at 0, 5, 10 or 15 mg/kg body weight daily for 7 successive days. Semen quality, serum testosterone concentration and fertility of treated mice were assessed. The results showed that the number of abnormal spermatozoa increased significantly and a significant decrease in spermatozoa with integrated acrosome was observed in males treated with T-2 toxin at all doses, As well, the amount of live spermatozoa decreased significantly in mice treated with 10 and 15 mg/kg body weight T-2 toxin. Low pregnancy rate and high fetal resorption rate were observed when females were mated with T-2 toxin-exposed males. Testicular and cauda epididymal sperm counts, efficiency of sperm production and serum testosterone concentration were significantly reduced in mice treated with T-2 toxin at all doses in a dose-dependent manner. In conclusion, these findings indicated that T-2 toxin presented toxic effects on reproductive system of adult male mice.