The Establishment Of A Mouse Model Of Premature Ovarian Failure Caused By Radiotherapy And The Preliminary Study Of MCL-1 Gene In Patients With Premature Ovarian Failure

Part?The establishment of premature ovarian failure in mouse model induced by radiotherapyObjective:To establish a mouse model of premature ovarian failure?POF?by radiotherapy and confirm its feasibility.Methods:Eight weeks C57BL6 female mice were exposed to a single X-ray irradiation at different doses of 0Gy,2Gy,4Gy,6Gy.Each group was analyzed the following indicators after 2 days and 7 days treatment:body weight,the ovarian wet weight,concentrations of serum gonadal hormone,number of ovarian follicles and the morphology of organs.While the 0Gy-and 4Gy-treated groups were followed up the above indicators for 2 weeks,3 weeks,4 weeks,6 weeks.Results:In the 2Gy-,4Gy-,6Gy-treated groups,7 days later the body weight lost and the ovarian weight reduced compared with 0 Gy group.2 days after the irradiation in6Gy group,the serum AMH level was obviously reduced compared with 0 Gy group.7 days after the irradiation,the serum FSH level was significantly increased and AMH level was decreased in the 4Gy-and 6Gy-treated groups.Compared to the 0 Gy group,7 days after the radiotherapy in the 2Gy,4Gy and 6Gy mice,the numbers of primordial follicles and growth follicles were significantly decreased?P<0.05?;and histological changes were observed in the liver,spleen and endometrium of the mice.Additionally,compared with 0Gy group,in 4Gy group the ovarian weight were reduced,the serum levels of FSH were gradually increased and the serum levels of E₂were dramatically decreased with the extension of post-irradiation time?P<0.05?.The numbers of primordial follicles and growth follicles were gradually decreased,and large number of atresia follicles was left in the ovary at 6 weeks post-irradiation.Conclusion:C57BL6 mice after the lowest suitable 4Gy irradiation from 1 week to 2weeks,the mice model of premature ovarian failure were successfully established.This mice model has the advantages of time saving,high success rate,low mortality,which might provide the experimental model for the study of clinical patients with premature ovarian failure.Part?The analysis of MCL-1 gene in Chinese women with idiopathic premature ovarian failureObjective:To investigate the relationship between myeloid cell leukemia-1?MCL-1?and idiopathic premature ovarian failure?POF?in Chinese women.Methods:200 idiopathic POF and 100 healthy controls were recruited in this study and the peripheral blood was collected.POF was defined as cessation of secondary amenorrhea for at least 4⁶ months before the age of 40 years along with the detection of serum follicle-stimulating hormone?FSH?concentrations>40 IU/L on two occasions at least 4 weeks apart.The genomic DNA was extracted from peripheral leukocytes.The entire coding region and splice sites of the MCL-1 gene were amplified by polymerase chain reaction?PCR?.Chi-square was used to assess the genotype distribution and allele frequency of single-nucleotide polymorphism between POF and control groups.Results:Three mutation of MCL-1 gene were identified namely c.-36C>T,c.-131C>T,c.78C>T.After data analysis,c.-36C>T and c.-131C>T in 5'-UTR were both found in POF group and control group,the genotyic distributions in POF group were as follows,c.-36C>T:CC 96.5%?193/200?,CT 3.5%?7/200?,TT 0%?0/200?,and c.-131C>T:CC 99%?198/200?,CT 1%?2/200?,TT 0%?0/200?.There was no difference in genotype distribution or allelic frequencies of these two variants between POF group and control group?P>0.05?.The synonymous variant?c.78C>T?in exon 1 which was discovered only in one of the control patients did not result in a change in amino acid sequence?p.Gly26Gly?.Conclusion:MCL-1 gene may not be associated with idiopathic POF in Chinese women.