Study The Mechanism Of Premature Ovarian Failure Using XY Female Sex-reversal Mice As A Model

Premature Ovarian Failure(POF)refers to Premature Ovarian Failure caused by multiple factors,which is one of the reasons affecting the decrease of reproductive rate of female animals.Clinically,hormone replacement therapy is the main therapy for POF,but it cannot fundamentally remove the cause of POF and causes a series of side effects.In this study,XY female sex reversal mice were used as the model to solve the problem of premature ovarian failure through ovarian transplantation,and to provide a unique perspective for the decline of animal fertility caused by premature ovarian failure.1.Ovarian function determination in XY female sex reversal miceXY female sex reversal mice and wild-type female mice at 30,60 and 120 days of age were selected to observe the cell morphological changes in each period of estrus cycle and determine the estrus cycle by crystal violet staining of vaginal secretion.The number and development of ovarian follicles were analyzed by HE staining.The levels of E2,FSH and melatonin were determined by ELISA.The results showed that there was no significant difference in the length of estrus cycle between XY female sex reversal mice and XX female mice.The E2 level of XY female sex reversal mice at 30 days of age and 60 days of age was significantly lower than that of wild type XX female mice(P<0.05),but the E2 level of XY female sex reversal mice at 120 days of age was significantly higher than that of XX female mice.At 120 days of age,the FSH level of XY female sex reversal mice and XX female rats was significantly increased(P<0.05);The level of melatonin in the follicular fluid of 60-day-old XY female sex reversal mice was significantly higher than that of XX female mice(P<0.05),indicating abnormal hormone secretion of XY female sex reversal mice.Organ index showed that the ovarian index of XY female sex reversal mice was significantly lower than that of XX female mice at 30-120 days of age,indicating ovarian dysplasia in XY female sex reversal mice.He staining of ovarian slices showed that there was no follicle development on the ovaries of XY female sex reversal mice from 60 days of age,indicating abnormal ovarian function in XY female sex reversal mice from 60 days of age.2.Effect of ovarian transplantation on female B6 miceIn order to further study the XY female sex reversal of ovarian dysfunction in mice,using the method of transplant surgery,ovarian and the side of the XY female sex reversal of mice to same day age of wild type XX on one side of the female mice,swapping ovary transplantation,at different times after HE staining to determine the ovarian morphological abnormalities,superovulation after statistical number of eggs,The egg quality was evaluated by immunofluorescence.The results showed that after the transplantation of the ovaries of XY female sex reversal mice to XX female mice,the morphology of the ovary was significantly improved,showing different levels of follicles.The number of oocytes was changed from untreated oocytes that could not be overdischarged to oocytes that could be obtained after transplantation,and the quality of the oocytes was poorer than that of the blank control group.The results indicated that the organism environment and ovarian sac microenvironment of XX female mice had a good effect on XY female sex reversal mice ovaries.On the other hand,when XX female mice were transplanted to one side of XY female sex reversal mice,the morphology of the other side of the ovary of XY female mice was improved,but only the original follicles were shown,and the number of eggs could not be obtained,indicating that the normal XX female mouse ovary had a certain saving function for the female ovary of XY female sex reversal mice.Without any treatment,oocytes could not be obtained from 60-day-old and 120-day-old XY female sex reversal mice after superovulation.Now,we transplanted the ovaries of XY female sex reversal mice to XX female mice(the other side kept its ovaries)at the age of 60 days and 120 days,and oocytes could be obtained from XY female sex reversal mice at the age of 60 days and 120 days after superovulation These results indicate that ovarian transplantation can improve the ovarian function of XY female sex reversal mice.In conclusion,XY female sex reversal mice have abnormal ovarian function at the beginning of 60 days of age,and ovarian transplantation can improve the ovarian function at the beginning of 60 days of age.