骨髓间充质干细胞移植对丙烯酰胺中毒大鼠脊髓组织细胞凋亡的影响

Bone marrow mesenchymal stem cell transplantation inhibits apoptosis in the rat spinal cord injured by acrylamide

背景:目前,针对丙烯酰胺导致的周围神经病变尚无有效的治疗方法,因此,探索新的治疗手段尤为重要。目的:探讨骨髓间充质干细胞对丙烯酰胺中毒大鼠脊髓损伤的保护作用及机制。方法:全骨髓贴壁法制备骨髓间充质干细胞,通过形态学观察、流式细胞仪检测表面标记物进行鉴定。将30只清洁级SD大鼠随机分成正常对照组、丙烯酰胺中毒组、骨髓间充质干细胞移植组,每组10只。丙烯酰胺中毒组大鼠给予丙烯酰胺50 mg/(kg·d)灌胃,每周连续灌胃染毒5 d,间隔2 d,共染毒2周。骨髓间充质干细胞移植组给予丙烯酰胺灌胃染毒2周后,尾静脉注射3×106个骨髓间充质干细胞,每周连续5 d,共3周。5周实验结束后处死SD大鼠,分离脊髓组织,通过苏木精-伊红染色观察脊髓组织形态,Tunel法检测脊髓组织细胞凋亡水平,Western-Blotting检测脊髓组织Bcl-2和Bax的蛋白表达。结果与结论:①丙烯酰胺中毒后,脊髓组织结构破坏,并出现明显的细胞凋亡,骨髓间充质干细胞移植后凋亡细胞显著减少、组织结构修复;②与丙烯酰胺中毒组相比,骨髓间充质干细胞移植组大鼠脊髓Bcl-2表达水平明显升高,而Bax表达水平明显降低,差异有显著性意义(P<0.05);③结果提示,骨髓间充质干细胞移植可抑制丙烯酰胺中毒导致的脊髓组织细胞凋亡,其机制可能与促进Bcl-2表达、抑制Bax表达有关。

BACKGROUND:Until now,there is no effective treatment for peripheral neuropathy caused by acrylamide.Therefore,it is necessary to explore new treatment methods.OBJECTIVE:To explore the protection role and its mechanism of bone marrow mesenchymal stem cells(BMSCs)against acrylamide-induced intoxication in the spinal cords of rats.METHODS:BMSCs were cultured by the whole bone marrow adherence method and identified by morphological observation and flow cytometry detection.Thirty Sprague-Dawley rats,clean grade,were randomly divided into three groups(n=10 for each group):normal control group,acrylamide group and BMSCs transplantation group.The latter two groups received acrylamide by gavage,50 mg/(kg?d),5 days per week,for 2 weeks with an interval of 2 days.Then,in the BMSCs transplantation group,3×106 BMSCs were transplanted by the caudal vein,5 days per week,for 3 consecutive weeks.Hematoxylin-eosin staining was utilized to observe the morphological changes of the spinal cord.Tunel assay was used to detect cell apoptosis.Western blot assay was adopted to detect the expression levels of Bcl-2 and Bax.RESULTS AND CONCLUSION:In the acrylamide-exposed rats,the damage to the structure was found in the spinal cords by morphological observation,which was significantly alleviated after BMSCs transplantation.The disturbed expression levels of Bax and Bcl-2 were also significantly inversed after BMSCs transplantation(P<0.05).These results suggest that BMSCs transplantation can inhibit cell apoptosis in the spinal cords of acrylamide-intoxicated rats,probably by up-regulating expression of Bcl-2 and down-regulating expression of Bax.