Study Of The Attenuating Effect Of Melatonin On The Fibrosis Of Mice Ovary Induced By Cyclophosphamide

Objective To investigate the damage and fibrosis effect of cyclophosphamide on mice ovary,and whether melatonin could effectively protect ovarian function and attenuate the fibrosis of mice ovary induced by cyclophosphamide.Methods The C57 mice in each group(Vehicle Group,Melatonin Group,CTX Group,CTX+Melatonin Group)were received premeditated drug treatment.In order to access the damage effects of cyclophosphamide on the mice ovarian function,and whether melatonin could effectively restore the ovarian function,the weight of all mice ovary was measured,and the ovarian morphology observation,follicle number counting of HE staining of ovarian tissue section,mouse vaginal smear and serum AMH concentration detection were also conducted.Then,according to the sirius red staining and immunohistochemical staining of ovarian tissue sections(Fibronectin),the ovarian fibrosis induced by cyclophosphamide in mice,and whether melatonin could attenuate the fibrosis were researched.Results Compared with the Vehicle group,according to the vaginal smear,the mice with injection of cyclophosphamide presented irregular or prolonged estrous cycle(0.67%,P=0.014).After the mice were executed,the quality of the mice was weighed and it was found that the weight of the mice treated with cyclophosphamide were 18.15±0.49 mg,which were much less than that of the Vehicle group(24.66±0.39 mg,P<0.001).The HE staining of ovarian tissue section showed that the ovarian morphology of mice with the treatment of cyclophosphamide was irregular or showed reduced volume,and each stage of healthy follicles(including primordial follicles,primary follicles,secondary follicles and antral follicles)were significantly decreased(P = 0.001,<0.001,<0.001 and < 0.001)while the number of atretic follicles were increased numerously(P<0.001).The mice serum concentrations of AMH in cyclophosphamide group were also significantly decreased compared with the Vehicle group(1.00 + 0.12 ng/ml,P=0.012).In addition,by means of Sirius red staining,fibronectin immunohistochemical staining,it was found that the total content of collagen fibrils of the mice ovary was obviously increased(P<0.001,and the positive area of the histochemical staining also increased,which indicated cyclophosphamide could induce fibrosis in mice ovary.Nevertheless,the additional administration of melatonin could efficiently attenuate these chemotherapy injuries.It showed that the weight of the mice ovary were greatly increased after the injection of melatonin(21.88±0.75 mg,P<0.001).In comparision with the mice in cyclophosphamide group,the proportion of irregular estrous cycle was decreased(33.3%,P=0.079).The ovarian morphology has a certain degree of recovery,the number of healthy follicles in various stages(including primordial follicle,primary follicle,secondary follicle and antral follicle)were obviously increased(P= 0.003,<0.001,<0.001 and <0.001),and the number of atretic follicles were significantly decreased as well(P=0.016).The serum concentration of AMH also showed somewhat increased(1.18±0.02ng/ml,P=0.235).Furthermore,according to Sirius red staining and Fibronectin immunohistochemical staining,it was showed that the total content of collagen fibrils of the mice ovary was substantially reduced(P<0.001),and the content of Fibronectin in mice ovary were decreased as well,which indicated that melatonin could effectively attenuate the fibrosis induced by cyclophosphamide on mice ovary.Conclusion Cyclophosphamide could induce the fibrosis on the ovary of C57 mice,and obviously declined the mice ovarian function.While the additional treatment of melatonin could effectively alleviate the ovarian fibrosis induced by cyclophosphamide,and restore ovarian function to a large extent.Melatonin,thereby,could provide strong protective effect on the injured mice ovary.