Effects of Maternal Cypermethrin Exposure During Lactation on Reproductive Development in Male Offspring
|School||Anhui Medical University,|
|Course||Nutrition and Food Hygiene|
|Keywords||Cypermethrin Lactation Male offspring Reproductive and developmental Testosterone Sperm quality|
Pesticides are an important class of environmental chemical contaminants, easy to residues in food. Cypermethrin is commonly used in a pyrethroid pesticides, widely used in crops, forest, gardening and indoor pest control. With cypermethrin use, expanding the scope, its toxicity to mammals is also a growing concern. Cypermethrin in adult mouse reproductive toxicity has been reported, but the lactating mother cypermethrin exposed male rats reproductive damage has not been reported. Studies have shown that male offspring during pregnancy and early postnatal exposure to environmental pollutants can cause reproductive and developmental damage, this experiment focuses on the early postnatal (lactation) exposure to maternal cypermethrin damage effects and mechanisms of reproductive development in male offspring. To clarify the lactating maternal exposure cypermethrin on the role and mechanism of male rats reproductive and developmental damage, the 21 healthy pregnant rats were divided into control group, low-dose cypermethrin group (6.25 mg / kg) and high-dose cypermethrin group (25 mg / kg ). Cypermethrin treated female rats after delivery day, 1 to 21 days given by oral gavage cypermethrin (6.25 mg / kg and 25 mg / kg, 10 ml / kg, dissolved in corn oil) treatment, female rats of the control group given volume corn oil. In postnatal day 21 groups of 15 male rats were sacrificed testis weighed and histopathological examination, RIA kit for detection of serum testosterone, estradiol, and testicular tissue testosterone levels by RT-PCR method detection of testicular StAR and testosterone synthase mRNA expression detected by Western blot Star and testosterone in the testes synthase protein expression levels by immunohistochemistry method to detect the number of Leydig cells, to detect testicular germ cell apoptosis by TUNEL method. The remaining male pups were weaned given normal diet to adulthood. 70 days after birth, the analysis of the quality of sperm in the epididymis to evaluate the fertility of adult male rats, testis weighed and histopathological examination, testosterone radioimmunoassay kit for detection of serum testosterone, estradiol and testicular testosterone levels Star and testosterone in the testes synthase mRNA expression was detected by RT-PCR method, Western blot analysis testis StAR and testosterone synthase protein expression levels, the number of Leydig cells detected by immunohistochemical method, using the TUNEL method testicular germ cell apoptosis. The results showed that, compared with the solvent control group, 21 days after birth, low dose cypermethrin exposure group male offspring body weight, testicular weight and testicular lower coefficient (P lt; 0.05 or P LT; 0.01). Histopathological examination revealed high and low doses of cypermethrin exposure group male rats seminiferous tube cavity diameter larger, fewer spermatogenic cell layers, less spermatogenic cells and irregular arrangement. 21-day high-dose group male rats testicular tissue after birth P450scc protein expression was lowered. Compared with the solvent control group, was born after 21 days of high-dose cypermethrin exposure group male rats serum T and testicular tissue T levels decreased (P lt; 0.01, P lt; 0.05), compared with low-dose cypermethrin exposure group, broken Period on high doses of cypermethrin exposure group male rats serum T levels lower (P lt; 0.05) Although adult male rats testis P450scc expression of serum and testicular tissue T are restored to the level of the control group, but the adult testicular histopathological still testicular seminiferous tube cavity diameter larger decrease in spermatogenic cell layer, cell Number of small and to Ordering relatively irregular change. Compared with the control group, the adult male offspring epididymal sperm count decreased significantly. Based on the above results, the study concluded that: (1) lactating mother cypermethrin exposure can cause long-term damage to testicular development and spermatogenesis in male offspring. (2) lactating maternal exposure CYPERMETHRIN the weaning period in male offspring reproductive endocrine interference to adulthood can be restored.