| Toxic effects of DEHP on the body had aroused great concern, Its health hazards related to male and female reproductive toxicity, embryonic development, genetic toxicity, immune toxicity, neurotoxicity, oxidative damage, et al. Biological damage of the female reproductive system caused by DEHP could not be ignored, had become the focus of attention of Environmental Medicine.Objective:Female reproductive system beard the important task of breeding and reproduction, to protect their fertility related to the health of future generations. Study about female reproductive toxicity of DEHP on the mother and offspring had important theoretical and practical significance. However, the literatures about female reproductive toxicity of DEHP were lesser, Characteristics of toxicity and mechanism of action were not clear yet. Therefore, this study observed the effects on the female reproductive organ and reproductive function caused by DEHP, explored the disrupting role of DEHP on the reproductive endocrine, provided the scientific basis for the comprehensive evaluation of the toxicology of DEHP and its effect on potential hazards of human reproduction system, and had theoretical and practical significance for protecting the health of residents and improving the quality of life.Methods:60 ICR female mice were randomly divided into 4 groups. One was as control group,the other three was as treated groups(125,500,2000 mg/kg/d). The experimental cycle was 16 weeks. Intragastric administration was once a day and every week for 6 days. Measuring weight was on a regular basis.The general growth conditions were observed, recording water, diet and weight change during the period of the experimental study. It began to observe the estrous cycle in ten days before death at 8:00 every morning by vaginal smears, studying the effect of DEHP on estrous cycle. Execute the mice during anoestrum after the weighing.Determination indicators are as follows:(1)Sample Blood in mice eyes,take the uterus and ovaries, calculate organ coefficient of the uterus and ovary,detect hormone levels of P4,E2,T in serum by radioimmunoassay. (2)Observe pathological changes by HE staining of uterine and ovarian,detect expression of ERαin endometrial tissue by immunohistochemistry.(3)Determine MDA content in the uterus by TBA, T-SOD vitality by xanthine oxidase method and protein content by UV spectrophotometry.(4)Staining of cells was by Propidium iodide (PI) single staining, FC500 flow cytometer detected and recorded the percentage and apoptosis of the cells in each phase.(5)Aromatase P450 mRNA expression in ovary determined by Real-time quantitative PCR.Result:1.The estrous cycles and Non-estrus of the duration in which the middle and high-dose group was significantly longer than that of control group(P<0.05); the estrus in each group had no significant difference(P>0.05).2.During the experiment and the end of the experiment, the body weight of mice exposed groups in each group had no significant difference(P>0.05).3.The weight of ovary in high-dose group was significantly higher than that of the control group(P<0.05); the ovarian organ coefficient of the middle and high-dose group was significantly longer than that of the control group(P<0.05). The weight of uterus gradually decreased as the dose increased, but the difference was not significant(P>0.05). The ovarian tissue of mice in the control group was normal, plasma cells and eosinophils infiltrated in the ovary of mice in low-dose group, the granule cells of ovarian follicles were acutely damaged, and the structure of granule cells appeared loose, degeneration, loss, the gap between granule cells and membrane cells widened, the structure of luteal cells appeared loose, plasma cells and eosinophils infiltrated. The uterine tissue of mice in the control group was normal,the nuclei of endometrium appeared pseudostratified phenomenon, the number of glands in the lamina propria reduced in the low-dose group, in middle and high-dose group thickness of endometrium was uneven, the epithelial hyperplasia and endothelial fibrosis was observed in the endometrium, the number of glands in the lamina propria reduced, the part of the glands werw depauperate in the middle and high-dose group.4.The MOD and IOD of endometrial ERαin the high-dose group was significantly higher that control and other dose group, the difference was significant (P<0.05); The IOD of endometrial ERαin the middle dose group was significantly higher that control and low-dose group, the difference was significant (P<0.05).5.The levels of E2 and T in each group had no significant difference(P>0.05),While the level of P4 in the middle and high-dose group were significantly lower than the control group and Low-dose group(P<0.05).6.The MDA levels and T-SOD activity of the uterus tissue in each group had no significant difference(P>0.05).7.The G0/G1 percentage of granulosa cells in high-dose group was significantly higher than the control group and low-dose group(P<0.05), and that of the high-dose group was significantly higher than middle-dose group(P<0.05). The S percentage of granulosa cells in the middle and high-dose group was significantly lower than the control and low-dose group(P<0.05), and that of low-dose group was significantly lower than the control group(P<0.05), high dose group was significantly lower than the middle dose group(P<0.05). The G2/M percentage of granulosa cells in the middle and high-dose group was significantly lower than the control and low-dose group(P<0.05). The apoptosis percentage of granulosa cell in the high-dose group was significantly higher than that of the control and low-dose group, the difference was significant(P<0.05), and that of the high-dose group was significantly higher than middle-dose group(P<0.05). 8.The expression of P450 arom mRNA in ovary of the mice in each group was no significant difference(P<0.05).Conclusion:1.DEHP can make the female mice exposed prolong estrous cycles and non-estrus, and the duration of estrous cycle was mainly due to that non-estrus was significantly prolonged.2.DEHP can make ovarian weight and organ coefficient of the female mice increase, structure of ovarian granulosa cells appeared loose, edema, degeneration, loss,the gap nuclear condensation, nuclear fragmentation and other obvious pathological changes, between granular cell and membrane cell widened, luteal cell structure appeared loose, plasma cells and eosinophils infiltrate, suggesting that ovary may be the main target organ of DEHP. 3 . The epithelial hyperplasia and endothelial fibrosis was observed in the endometrium, the number of glands in the lamina propria reduced, the part of the glands were depauperate, the expression of ERαin endometrial tissue increased in experimental groups, suggesting that DEHP may not simulate the estrogen but change the body's natural ERαlevels to impact endocrine system.4.DEHP can reduce levels of P4 in serum, and have disrupting role on the reproductive endocrine.5.DEHP can increase the G0/G1 percentage of granulosa cells granulosa cells in female mice, decrease S and G2/M percentage, and promote apoptosis of granulosa cell. DEHP can cause change of reproductive organs and reproductive endocrine function, may have female reproductive toxicity on female mice, and have disrupting role on the reproductive endocrine.
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