Therapeutic Effect And Mechanism Study Of Menstrual Blood-derived Endometrial Stem Cells Transplantation On Endometrial Injury

BackgroundIntrauterine adhesion(IUA)is a major cause of female infertility.Generally,IUA is characterized by hypomenorrhea,amenorrhea,infertility,and recurrent miscarriages,and is often linked to endometrial injury caused by intrauterine operation.In patients with severe IUA,it is difficult to restore fertility with conventional therapeutic methods such as hysteroscopic adhesiolysis and hormone supplementation.Recently,Menstrual blood derived stromal cells(MenSCs)which derived from the shedding endometrium have been investigated for their capacity of promoting endometrial regeneration.Therefore,based on this project,we will preliminarily clarify the imprvement and potential mechanism of MenSCs-based therapy for IUA,and provide supports for appling MenSCs on the treatment of patients with IUA and other tissue damage diseases.Objective1.To establish a stable and minimally invasive animal model of IUA that conforms to the clinicopathologic characteristics.2.To determine the therapeutic effects of MenSCs on endometrial injury at animal level.3.To explore the potential mechanisms of MenSCs on the repair of endometrial injury at molecular level.Methods1.The menstrual blood samples were collected from healthy female donors and isolated by routine methods.MenSCs was identified through analyzing immunophenotype and multiple differentiation potential.2.Construction and optimisation of an endometrial injury model in mice by transcervical ethanol perfusion.3.HE staining was used to examine the difference of endometrial thickness and number of glands in IUA group and IUA/MenSCs group.4.Masson staining was used to detect the degree of endometrial fibrosis in IUA group and IUA/MenSCs group.5.Immunohistochemical staining and western blotting were used to detect the endometrial angiogenesis,inflammation and cell proliferation in IUA group and IUA/MenSCs group.6.Western blotting was used to detect the expression of key factors in PI3K/Akt signal pathway after MenSCs transplantation.Results1.MenSCs were successfully isolated from healthy female donors.And our results demonstrate that all the MenSCs isolated in our study conform to the standards of mesenchymal stem cells.2.After the establishment of the IUA model,HE staining results showed that both the thickness and number of glands in the endometrium were significantly decreased and Masson staining showed that endometrial fibrosis was obvious.Immunohistochemical staining results showed that the expression of CD31 in the endometrium decreased significantly,while that number of macrophages increased significantly,and the fertility rate decreased significantly.3.The endometrial thickness in the IUA/MenSCs group was significantly increased in comparison to that in the IUA group after treatment with MenSCs for 15 days.The number of endometrial glands were significantly increased.The levels of endometrial fibrosis in the IUA/MenSCs group were notably decreased.4.MenSCs transplantation can promote endometrial cell proliferation and angiogenesis,reduce endometrial inflammation,improve endometrial receptivity and increase the fertility and the number of embryos.5.Western blotting results demonstrated that MenSCs transplantation can restore endometrial function by activating PI3K/Akt signal pathway,which could promote the regeneration of endometrial cells and reduce their apoptosis.Conclusion1.This study successfully establish a mouse model of IUA by transcervical ethanol perfusion in a minimally invasive manner.2.MenSCs transplantation is likely to improve the endometrial function by activating PI3K/Akt signal pathway in IUA animal model.