TGF-β/Smads信号通路在干细胞移植治疗化疗损伤性卵巢早衰中的分子机制

It was noticed that young women who have been diagnosed as tumor and treated with the chemotherapy would result in the suppression of some specific signaling pathways. This could induce the premature ovarian failure (POF) which would perform as infertility and decreased life quality. Reactivating these signaling pathways could help rebuild the normal ovarian function. Previous research have shown that the cytokines secreted by the mesenchymal stem cells played crucial role on the microenvironment of follicle development. In this study, rats performed as POF which induced by the alkylating agent would be used as the animal models. Littermates treated with the estradiol valerate would be taken as the controls. The transplantation of the human placenta-derived mesenchymal stem cells and the rat marrow mesenchymal stem cells would be conducted for both groups. The expression of TGF-β/Smads signaling pathway and ovary related genes or proteins, the targetted position of stem cells, the serum hormone levels before and after the trasplantation would be measured with the real-time polymerase chain reaction,the high resolution melting method,the immunohistochemistry,Western blot,the laser confocal and intravital imaging techniques, respectively. Molecules of the TGF-β/Smads signaling pathway which have close correlation for the repairment of ovarian function and the modification of genetic epigenetic inheritance would be studied. The fertility of both groups after the transplantation would be measured as mating with the male littermates. This study would yield novel information on the improvement of ovarian dysfunction and the retrieving of female fertility by detecting mechanisms of the stem cell transplantation therapy for POF.

年轻女性因肿瘤接受化疗导致卵巢内特定的信号被抑制，可不同程度地出现卵巢早衰(POF)并致不孕，严重影响她们的生活质量，因此激活此信号通路有可能恢复卵巢功能。有研究显示移植的间充质干细胞旁分泌的细胞因子和生长因子能够改善卵泡生长微环境。本项目针对烷化剂所致POF大鼠模型，以戊酸雌二醇治疗POF为对照，采用大鼠骨髓间充质干细胞和人源胎盘间充质干细胞移植治疗化疗损伤性POF，应用Real-time PCR、高分辨率熔解曲线法、免疫组化、Western blot、激光共聚焦及活体成像技术研究干细胞移植前后与TGF-β/Smads通路相关和大鼠卵巢功能相关的基因、蛋白的表达、干细胞定位、内分泌功能，明确干细胞移植前后基因的表观遗传修饰及通路中相关因子在修复POF中的作用，并与雄鼠合笼评估其生殖能力，探讨化疗损伤后干细胞移植治疗POF的分子机制，为POF患者改善卵巢功能和恢复生育能力提供科学依据。

目的: 探讨化疗药物环磷酰胺(CTX)致大鼠卵巢早衰(POF)模型的血清生殖激素水平、卵巢细胞凋亡和间质损伤等特征；移植鼠源骨髓间充质干细胞 (BMSCs)移植对卵巢中转化生长因子β受体Ⅱ (TGF-βRⅡ) 表达的影响；人胎盘间充质干细胞（hPMSCs）移植治疗对环磷酰胺所致卵巢早衰模型（POF）SD大鼠后超氧化物歧化酶(SOD1)和解耦联蛋白2（UCP-2）表达的影响。.方法:以10周龄雌性SD大鼠为研究对象,以50mg•kg-1的首剂量腹腔注射环磷酰胺,再以8mg•kg-1连续腹腔注射14d,建立POF模型。将正常动情周期的SD雌性大鼠48只随机分为对照组、模型组 (环磷酰胺致POF) 、造模后自然恢复组和BMSCs移植组 (尾静脉移植) 和hPMSC移植组。分别于建模后、BMSCs移植后取各组卵巢组织, VG染色和HE染色, 光镜下观察卵巢组织形态和计数各组卵泡数。免疫组织化学法和Western blot检测各组卵巢组织TGF-βRⅡ及SOD1和UCP-2蛋白表达的情况。.结果:CTX致大鼠模型的血清生殖激素异常,卵巢间质纤维化,颗粒细胞凋亡,大鼠卵巢功能过早衰竭。BMSCs移植可改善由化疗导致卵巢早衰的功能部分恢复, TGF-βRⅡ可能参与了移植BMSCs修复化疗后POF的过程。hPMSC移植改善卵巢早衰SD大鼠氧化应激和SOD1及UCP-2表达，起到保护卵巢线粒体功能的作用。