骨髓间充质干细胞对老年大鼠受压组织炎症性损伤的影响

Effect of bone marrow mesenchymal stem cells on inflammatory injury in aged rats tissue under pressure

目的研究骨髓间充质干细胞(BMMSCs)对老年大鼠受压组织炎症性损伤的影响,以期为BMMSCs用于老年压疮的临床治疗提供动物实验依据。方法将40只SPF级雄性老年SD大鼠(喂养16月)随机分成正常组、模型组、BMMSCs移植组和生理盐水组。倒置显微镜下观察雄性Wistar大鼠的BMMSCs形态学变化;流式细胞仪检测BMMSCs表面标记物CD105、CD45、CD44、CD29的表达;生化检测基质细胞衍生因子-1(SDF-1)及白细胞介素-6(IL-6)的表达。肉眼观察BMMSCs干预后压疮疮面的愈合情况。结果分离所得细胞能在体外传代培养;流式细胞仪检测发现细胞阳性表达CD44、CD29,阴性表达CD105、CD45;生化实验提示:与正常组比较,模型组中SDF-1和IL-6表达量显著上升,BMMSC移植组中SDF-1和IL-6表达量显著下降,差异有统计学意义(P<0.01)。BMMSCs移植组压疮疮面愈合远远高于生理盐水组(P<0.01)。结论 BMMSCs在SDF-1趋化作用下迁移归巢到受压损伤的组织,通过抑制细胞炎症因子IL-6的释放,降低损伤组织的炎症反应,在老年大鼠压疮疮面修复愈合中起着重要作用。

Objective To study the effect of bone marrow mesenchymal stem cells（ BMMSCs） on inflammatory injury in tissues of aged rats under pressure and to provide a new source of seeding cells for clinical uses. Methods Forty SPFgraded male SD rats,which were fed for 16 months,were randomly divided into normal group,model group,BMMSCs transplantation group and saline group. The morphological changes of BMMSCs of male Wistar rats were observed under the inverted microscope; The expression of surface markers-CD105,CD45,CD44 and CD29 of BMMSCs were detected by flow cytometry. The levels of interleukin-6（ IL-6） and stromal cell derived factor-1（ SDF-1） were also measured. And the healing rate of the pressure ulcer after intervention were observed. Results The isolated cells were able to be cultured in vitro; the expressions of CD44 and CD29 were positive while the expression of CD105 and CD45 were negative; The concentration of SDF-1 and IL-6 of the rats in the model group were significantly higher than those in the normal group（ P〈0. 01） while those in the BMMSCs transplantation group were significantly lower than those in the model group（ P〈0. 01）. The healing rate of the BMMSCs transplantation group was much higher than that of the saline group. Conclusions BMMSCs is able to move to injuried tissues by the chemotaxis of SDF-1,and reduce the inflammatory response in injuried tissues by inhibiting the release of IL-6,therefore,BMMSCs plays an important role in healing of pressure ulcers in the aged rats.