脐带间充质干细胞调节炎性微环境干预急性肾损伤的效应研究

目的：观察移植外源性脐带间充质干细胞（UC-MSCs）对小鼠急性肾损伤（AKI）炎性微环境的影响及对肾组织的修复作用。方法：分离培养孕后期C57BL/6雌性小鼠的UC-MSCs。另取雌性C57BL/6小鼠60只,随机分为正常对照组、AKI组、AKI＋MSC移植组,每组20只。AKI组和AKI＋MSC组用微型动脉夹夹闭小鼠双侧肾蒂45 min复制AKI模型,并于模型制备成功时腹腔内注射生理盐水0.2 ml（AKI组）或1＆#215;106 UC-MSCs（AKI＋MSC组）。于第2天和第7天每组活杀10只小鼠,取眼球血及肾组织,检测血尿素氮（BUN）及血肌酐（SCr）水平；肾组织行HE染色,观察组织病理学变化；ELISA法检测肾组织匀浆中促炎因子IL-1β、TNF-α、干扰素-1（IFN-1）及抗炎因子碱性成纤维细胞生长因子（bFGF）、IL-10、B淋巴细胞瘤-2（Bcl-2）的水平。结果：2 d时AKI组小鼠肾小管上皮细胞肿胀,胞质空泡性变,BUN和Cr均显著高于正常对照组,提示造模成功后肾小管受损严重,7 d稍有减轻；AKI＋MSC移植组小鼠肾功能在2 d时较AKI组有所恢复,肾组织病理学变化明显减轻（P＜0.01）,7 d基本恢复正常。ELISA结果显示,与正常对照组比较, AKI组各时间点肾组织匀浆中促炎因子的水平均显著升高（P＜0.01或P＜0.05）,抗炎因子的水平均显著降低（P＜0.01或P＜0.05）,2 d较7 d更加明显。各时间点AKI＋MSC组抗炎因子的水平较AKI组明显升高,促炎因子的水平明显下降,但与正常对照组比较差异均有显著性（P＜0.01或P＜0.05）,7d较2 d改善更明显。结论：MSC可通过减轻AKI肾组织炎症反应,调节损伤肾脏组织微环境中的细胞因子水平发挥保护肾损害的修复作用。

Effects of umbilical cord mesenchymal stem cells on regulating renal inflammatory microenvironment of kidney in mice with acute kidney injury

Objective：To observe the effect of exogenous umbilical cord mesenchymal stem cells （UC-MSCs）on inflammatory microenvironment and repair of kidney tissue in mice with acute kidney inj ury （AKI）induced by is-chemia/reperfusion injury. Methods：UC-MSCs were isolated from umbilical cords of pregnant C57BL/6 mice and cultured. Sixty healthy female C57BL/6 mice were randomly divided into normal control group,AKI group,and AKI＋MSC group （n=20）. AKI model was replicated by clamping bilateral renal pedicles for 45 minutes followed by release of clamping. Meanwhile,1＆#215;106 UC-MSCs were injected intraperitoneally in the AKI＋MSC group, and 0.2 ml normal saline was injected instead of UC-MSCs in AKI group. On 2,7 days after the model estab-lished,10 mice of each group were sacrificed respectively,blood and renal tissues were sampled for detecting ser-um creatinine （SCr）and blood urea nitrogen （BUN）levels,or assessing the pathological changes in renal tissue after HE staining. The levels of tumor necrosis factor-α（TNF-α）,interleukin-1β（IL-1β）,interferon-1 （IFN-1 ）, basic fibroblast growth factor （bFGF）,interleukin-10 （IL-10）,B lymphocyte tumor-2 （Bcl-2 ）of renal tissue homogenate were determined by enzyme-linked immunoadsorbent assay （ELISA）. Results：On day 2 ,the lev-els of BUN and SCr in AKI group were much higher than those in the normal control group,and pathological changes in renal tubule showed significant swelling and vacuolation of epithelial cells,but they were all alleviated on day 7. Compared to those in the AKI group,the levels of BUN and SCr in AKI＋MSC were much lower （P〈0.01）,while pathological changes were mild in AKI＋MSC group on day 2,and they recoverd on day 7. ELISA showed that the levels of pro-inflammatory factors （IL-1β,TNF-α,IFN-1 ）in kidney tissue of AKI group in-creased significantly （P〈0.05 or P〈0.01）,while the levels of anti-inflammatory factors （bFGF,IL-10,Bcl-2） decreased significantly compared to the nor