p38MAPK信号通路参与BMP2诱导MSCs的归巢效应研究

p38 mitogen-activated protein kinase signal pathway participates in the mesenchymal stem cells homing induced by bone morphogenetic protein 2

目的探讨p38丝裂原活化蛋白激酶(MAPK)信号通路在参与骨形态发生蛋白2(BMP2)诱导间充质干细胞(MSCs)向骨组织归巢中的作用。方法将MSCs细胞分别在含有终浓度为0、50、100、200μg/L BMP2的培养基下培养24 h,分析BMP2对细胞活力(CCK-8法检测)、细胞侵袭能力(Transwell实验检测)以及对p38MAPK的影响(Western blot和qPCR分别检测p38MAPK的蛋白和mRNA表达)。将发育良好的MSCs分为四组:对照组、BMP2组(100μg/L)、SB202190(p38MAPK抑制剂,10μg/L)组和BMP2+SB202190组,分析BMP2诱导MSC侵袭以及向骨组织归巢的机制。结果BMP2可剂量依赖性的促进MSCs细胞侵袭和上调p38MAPK蛋白的表达(P均<0.01)。BMP2和p38MAPK抑制剂SB202190单独作用以及联合作用对MSCs细胞活力的影响差异无统计学意义(P均>0.05)。与对照组侵袭细胞数[(31.54±2.56)个]相比,BMP2组侵袭细胞数[(87.25±4.78)个,P<0.01]显著增高,SB202190组侵袭细胞数[(9.87±2.14)个,P<0.01]显著降低。BMP2可以促进上调基质金属蛋白酶(MMP)2、MMP9和E-钙黏蛋白(E-cadherin)mRNA的水平并下调N-钙黏蛋白(N-cadherin)mRNA的水平(P均<0.01),而SB202190可以逆转BMP2对细胞的影响(P<0.01)。p38MAPK蛋白水平在BMP2组显著高于对照组,而在SB202190组显著低于对照组,在BMP2+SB202190组显著低于BMP2组(P均<0.01)。结论BMP2具有促进MSCs侵袭和促进MSCs向骨组织归巢的作用,这可能与BMP2上调p38MAPK途径有关。

Objective To investigate the role of p38 mitogen-activated protein kinase(p38 MAPK) signal pathway in the mesenchymal stem cells(MSCs) homing to bone tissue induced by bone morphogenetic protein 2(BMP2).Methods MSCs were cultured in medium containing 0,50,100 and 200 μg/L BMP2 for 24 hours.The effects of BMP2 on cell viability(CCK-8 assay),cell invasion(Transwell assay) and p38 MAPK(Western blot and qPCR were used to detect the protein and mRNA expression of BMP2).The well-developed MSCs were divided into four groups:control group,BMP2 group(100 μg/L),SB202190(p38 MAPK inhibitor,10 μg/L) group and BMP2+SB202190 group.The mechanism of MSCs invasion and homing to bone tissue induced by BMP2 was analyzed.Results BMP2 promoted MSCs cell invasion and upregulated p38 MAPK protein expression in a dose-dependent manner(all P<0.01).There was no significant difference in the effect of using BMP2 or p38 MAPK inhibitor SB202190 alone or in combination on MSCs cell viability(all P>0.05).Compared with the number of invasive cells in the control group [(31.54 ± 2.56)],the number of invasive cells in the BMP2 group [(87.25 ± 4.78),P<0.01] was increased significantly,and that in the SB202190 group [(9.87 ± 2.14),P<0.01] was significantly reduced.BMP2 promoted the up-regulation of MMP2,MMP9 and E-cadherin mRNA and down-regulation of N-cadherin mRNA(all P<0.01),while SB202190 reversed the effect of BMP2 on cells(all P<0.01).The p38 MAPK protein level of BMP2 group was significantly higher than that of control group,while the p38 MAPK protein level of SB202190 group was significantly lower than that of control group,and the p38 MAPK protein level of BMP2+SB202190 group was significantly lower than that of BMP2 group(all P<0.01).Conclusion BMP2 could promote MSCs invasion and homing to bone tissue,which may be related to the up-regulation of p38 MAPK signal pathway by BMP2.