缺血再灌注肾损伤微环境影响骨髓间充质干细胞表面CXC趋化因子受体-4表达

Effect of ischemia reperfusion-injured kidney microenvironment on CXC chemokine receptor 4 expression in bone mesenchymal stem cells in vitro

目的 观察缺血再灌注（I/R）肾损伤微环境对大鼠骨髓间充质干细胞（BMSCs）表面CXC趋化因子受体-4（CXCR4）表达及肾保护性细胞因子分泌的影响.方法 制作不同浓度I/R肾损伤组织匀浆,与BMSCs共培养.激光共聚焦显微镜观察BMSCs表面CXCR4受体表达;Transwell实验检测BMSCs向基质细胞源性因子-1（SDF-1）的迁移能力;逆转录-聚合酶链反应（RT-PCR）法检测基质细胞源性因子-1α（SDF-1α）、CXCR4、肝细胞生长因子（HGF） mRNA表达.结果 I/R肾损伤匀浆诱导BMSCs表面CXCR4表达明显上升（P＜0.01）;该表达可被CXCR4中和抗体所抑制（P＜0.05）.CXCR4表达增加后,BMSCs向SDF-1的迁移能力增强[（26.72±5.61）、（30.44 ±6.03）、（38.92 ±6.79）/cm2比（18.47 ±5.02）/cm2,P＜0.01].I/R肾损伤匀浆能够显著上调SDF-1α mRNA表达,但各组间表达差异无统计学意义（P＞0.05）.肾损伤匀浆能够显著上调CXCR4mRNA（3.11 ±0.24比2.02 ±0.17,P＜0.01）和HGF mRNA（3.01 ±0.46比1.99 ±0.21,P＜0.01）表达,表达随匀浆浓度增加而升高,升高的表达可被CXCR4中和抗体所抑制（1.86±0.11,1.78±0.22,P＜0.05）.结论 I/R肾损伤微环境能够通过提高BMSCs表面CXCR4受体表达促进BBMSCs迁移,活化的BMSCs上调保护性细胞因子表达,形成有利于肾损伤修复的微环境.

Objective To explore the effect of ischemia reperfusion-injured （IRI） kidney homogenate in vitro on CXC chemokine receptor 4 （CXCR4） expression in bone mesenchymal stem cells （BMSCs） and renal protective growth factors paracrine.Methods The renal homogenate supernatant of IRI model was built and co-cultured with BMSCs.CXCR4 protein expression was detected by laser focal microscope,chemotactic ability of BMSCs to stromal cells derived factor-1α （SDF-1α） was investigated by Transwell test,and the mRNA expression of SDF-1α,CXCR4 and hepatocyte growth factor （HGF） was detected by reverse transcription-polymerase chain reaction （RT-PCR）.Results CXCR4 protein expression was increased significantly after co-culture of BMSCs with IRI homogenate [2.54 ± 0.22 vs.1.26 ± 0.18,P 〈0.01）,which ould be decreased by CXCR4 neutralizing antibody,and the chemotactic ability of BMSCs to SDF-1 increased at the same time [（26.72 ±5.61）,（30.44 ±6.03）,（38.92 ±6.79）/cm2 vs.（18.47 ±5.02）/cm2,P 〈0.01].SDF-1α mRNA expression was increased in IRI group,but had no significan difference among groups （P 〉 0.05）.CXCR4 mRNA （3.11 ± 0.24 vs.2.02 ± 0.17,P 〈 0.01） and HGF mRNA （3.01 ±0.46 vs.1.99 ±0.21,P 〈0.01） expression was increased significantly with the homogenate,and the expression could be restrained by CXCR4 neutrlizing antibody （1.86 ± 0.11 and 1.78 ± 0.22,P 〈0.05）.Conclusion IRI kidney microenvironment can promote chemotactic ability of BMSCs by increasing BMSCs surface CXCR4 expression,and then CXCR4 ＋ BMSCs possessed the paracrine capabilities which promoted the recovery of the injured kidney.