骨髓间充质干细胞对脓毒症急性肺损伤大鼠肺内NF-κB影响的研究

Impact study of bone marrow mesenchymal stem cells on NF-κB in rat with acute lung injury

目的建立大鼠脓毒症急性肺损伤模型,探讨骨髓间充质干细胞(BMSCs)在脓毒症大鼠急性肺损伤中的肺保护作用及可能机制,为临床治疗脓毒症急性肺损伤提供新的理论和实验依据。方法全骨髓培养法制备BMSCs。36只成年Wistar大鼠(150±15)g随机分为3组,Sham组、CLP组和BMSCs组,每组12只,CLP组和BMSCs组采用盲肠结扎穿孔术(CLP)建立脓毒症急性肺损伤模型,盲肠根部丝线结扎,盲肠切口5 mm,肠内容物漏出,将其回纳入腹腔,关腹。Sham组大鼠仅翻动盲肠,不结扎穿孔。BMSCs组术后经尾静脉注射BMSCs细胞悬液1 ml(1×106/ml)。实验结束后,应用ELISA测定血浆IL-10、MIP-2水平,左肺采用Western blot测定肺内NF-κB的表达水平,右肺制作病理切片,HE染色,并在光镜下观察肺组织病理结构改变。结果 CLP组的血清MIP-2水平明显高于Sham组和BMSCs组,BMSCs组的血清MIP-2水平明显高于Sham组,差异有统计学意义(P<0.05);3组的血清IL-10水平比较差异无统计学意义(P>0.05);3组的NF-κB表达水平比较差异有统计学意义(P<0.05)。肺组织病理结果示CLP组和BMSCs组肺内大量炎症细胞浸润、肺间质水肿、肺内出血,BMSCs组症状较CLP组明显减轻。结论脓毒症急性肺损伤时,血浆MIP-2表达明显升高,肺内出血、水肿、大量炎症细胞浸润。BMSCs通过调控肺内炎症细胞NF-κB入核,使其促炎细胞因子MIP-2表达减少,减少中性粒细胞浸润起肺保护作用,暂不能说明BMSCs对IL-10有影响。

Objective To establish a rat model of acute lung injury with sepsis,to investigate the protective effect and possible mechanism of bone marrow mesenchymal stem cells（BMSCs）in acute lung injury with sepsis in order to provide new theoretical and experimental basis in rat of acute lung injury with sepsis in clinic. Methods BMSCs was cuhured by whole bone marrow cuhure.36 adult Wistar rats（150±15） g were randomly divided into three groups（Sham group,CLP group and BMSCs group）,12 rats in each group.The method（cecal ligation and puncture（CLP）sepsis established model of acute lung injury,cecal ligation thread roots,cecal incision 5 mm,intestinal contents leaking it back into the abdominal cavity,the abdomen was closed）was used in CLP group and BMSCs group.Just flip the cecum,without ligation and puncture was used in Sham group.BMSCs group was injected via the tail vein BMSCs cell suspension 1 ml （l×10^6/ml）.After the end of the experiment,plasma IL-10,MIP-2 levels were measured by ELISA, NF-κB expression level in lung left was measured by Western blot,the right lung were made in pathological section,HE staining was used and change of lung tissue was observed in the hght microscope structure. Results MIP-2 level of CLP group was significantly higher than that of Sham group and BMSCs group respectively,MIP-2 level of BMSCs group was significantly higher than that of Sham group,with statistical difference （P〈0.05）.IL-10 of three groups was compared,with no statistical difference （P〉 0.05）.NF-KB of three groups was compared,with statistical difference（P〈0.05）. Conclusion MIP-2 significantly increased when acute lung injury with sepsis,pulmonary hemorrhage,edema and inflammatory cell infiltration.BMSCs lung inflammatory cells can reduce proinflammatory cytokines MIP-2 expression by regulating NF-κB into the nucleus and reduce the infiltration of neutrophils,it plays a protective role in the lung.Temporarily can not explain BMSCs affect IL-10.