骨髓间充质干细胞移植对环磷酰胺诱导卵巢损伤大鼠Bax及Bcl-2蛋白表达的影响

Influence of bone marrow mesenchymal stem cells transplantation on Bax and Bcl-2 protein expression in cyclophosphamide-induced ovarian damage rats

目的探讨骨髓间充质干细胞(BMSCs)对环磷酰胺(CTX)所致卵巢损伤的保护作用。方法 30只Sprague Dawley大鼠随机分为空白对照组、模型组及细胞移植组,每组10只,空白对照组大鼠腹腔注射生理盐水,模型组及细胞移植组大鼠腹腔注射CTX制备卵巢早衰模型,细胞移植组于第1天注射CTX后24 h经尾静脉移植BMSCs。停药1周后处死所有大鼠,剖腹取卵巢测质量,观察卵泡数量变化,用免疫组织化学法及Western blot法测定卵巢组织中Bax、Bcl-2蛋白表达。结果模型组、细胞移植组大鼠总卵泡数、中大卵泡数及卵巢湿质量低于空白对照组(P<0.05),但细胞移植组大鼠总卵泡数、中大卵泡数及卵巢湿质量高于模型组(P<0.05)。空白对照组Bax主要表达于黄体细胞,卵泡颗粒细胞仅见散在Bax表达;模型组Bax主要表达于颗粒细胞的细胞质,尤其在闭锁卵泡、生长卵泡及窦状卵泡中表达明显;细胞移植组卵泡颗粒细胞中Bax表达范围明显小于模型组。空白对照组Bcl-2在各级卵泡颗粒细胞及黄体细胞中表达量均多,模型组Bcl-2在卵泡颗粒细胞仅散在表达,细胞移植组Bcl-2表达范围明显大于模型组。与空白对照组比较,模型组、细胞移植组大鼠卵巢组织中Bax蛋白表达量明显升高(P<0.05),Bcl-2蛋白表达量明显下降(P<0.05);但与模型组比较,细胞移植组大鼠卵巢组织中Bax表达量明显下降(P<0.05),Bcl-2表达量明显升高(P<0.05)。结论 BMSCs移植能通过调整卵巢组织中Bax、Bcl-2表达水平减少CTX对卵巢功能的损伤。

Objective To study the protective effects of bone marrow mesenchymal stem cells （BMSCs） on cyclophosphamide （CTX）-induced ovarian damage rats. Methods Thirty Sprague Dawley rats were randomly divided into blank control group, model group and cell transplantation group with 10 rats in each group. Rats of blank control group were intraperitoneally injected normal saline, and rats of model group and cell transplantation group were injected with CTX intraperitoneally for preparing premature ovarian failure model, furthermore, cell transplantation group was transplantated BMSCs through tail vein about 24 h after the injection of CTX. All the rats were sac6.ficed one week after drug withdrawal. The ovaries was obtained by cutting the belly open, then the mass of ovaries was measured and the number of ovarian follicle was observed. The expressions of Bax and Bcl-2 protein in ovaries were detected by immunohistochemical method and Western blot. Results The total number of follicles, the number of larger-follicles, wet weight of ovarian in model group and cell transplantation group were lower than those in blank control group （P 〈 0.05 ）, but the total number of follicles, the number of larger-follicles and wet weight of ovarian in cell transplantation group were higher than those in the model group（ P 〈 0.05 ）. In blank control group, Bax protein mainly existed in the luteal cells and little existed in granulosa ceils of follicles ; and in model group, Bax protein mainly existed in granular cytoplasm of granulosa cells of follicles, especially in the atretic follicles, growing follicles and antral follicles ; and in cell transplantation group, the range of Bax protein in granulosa cells was significantly less than that in model group. Bcl-2 protein existed extensively in the granulosa cells and luteal cells in blank control group;and Bcl-2 protein only scattered in few granulosa cells in model group;and in cell transplantation group, the range of Bel-2 was significantly larger than that in model group. Compared with blank control group, the expression of Bax protein increased significantly （P 〈 0.05 ） and the expression of Bcl-2 protein was significantly decreased （P 〈 0.05 ） in model group and cell transplantation group;but compared with model group, the expression of Bax protein significantly decreased （ P 〈 0.05 ） and the expression of Bcl-2 was significantly increased （ P 〈 0.05 ） in cell transplantation group. Conclusion Transplantation of MBSCs can reduce the CTX-included damage of ovarian by adjusting Bax and Bcl-2 level in ovarian tissue.