中介素抗过氧化氢诱导的BMSCs凋亡作用及机制探讨

The effect and mechanism investigation of intermedin on the apoptosis of bone marrow derived mesenchymal stem cells induced by hydrogen peroxide

目的探讨中介素（IMD）对过氧化氢（H2O2）诱导的骨髓源间充质干细胞（BMSCs）凋亡的影响及可能机制。方法应用骨髓细胞贴壁培养法获得大鼠BMSCs；将10μmol／L的IMD预处理BMSCs30min后，换用含100μmol／LH2O2的完全培养基处理2h，应用流式细胞术检测细胞凋亡情况；Western印迹和免疫荧光检测IMD对凋亡相关蛋白的表达情况；并检测IMD对ERK1／2磷酸化水平的影响；进一步在IMD干预前用特异性抑通路制剂阻断ERK1／2信号途径，观察其对IMD作用的影响。结果IMD可使BMSCs内ERK1／2通路磷酸化水平升高（P〈0．01）。与对照组和IMD两组相比，在H20：组中加入H202后细胞凋亡率则增加至55．9％（P〈0．01）；但在IMD＋H：O：组中细胞凋亡率为15．7％，与对照组和IMD组相比细胞凋亡率增加，但较H2O2组显著降低（P〈0．01）。IMD预处理可明显减少由H2O3介导的BMSCs凋亡，且促凋亡蛋白Caspase-3及Bax的表达减少，抗凋亡蛋白Bcl-2的表达增高（P〈0．01），ERKl／2通路特异性抑制剂U0126预处理后该作用消失。结论IMD可激活BMSCs内ERKl／2信号通路，调节凋亡相关蛋白的表达，减少由H202诱导的BMSCs凋亡。激活ERKl／2通路参与了其抗凋亡作用的调控。

Objective To investigate the effect and mechanism of intermedin （IMD） on the apoptosis of BMSCs induced by H202 and its mechanism. Methods BMSCs being cultured in vitro. After 30 rain pretreatment with 10-6mol/L IMD, cells were cultured in presence of 100 μ mol/L H202 for 2 hour, cell apoptosis was determined by flow cytometry; Apoptosis related protein expression was determined by Western blotting and immunofluorescence ; Protein and phosphorylation of ERK1/2 was detected by Western blotting and observe the influence of IMD after pretreatment with inhibitor of ERK1/2. Results IMD could increase phosphorylation of ERK1/2 pathway of BMSCs （ P 〈 0. 01 ）. Pretreatment of IMD could decrease BMSCs apoptosis induced by H202, and up regulation expression of Caspase-3 and Bax, down regulation expression of Bcl-2 （ P 〈 0. 01 ） , and the effect was abrogated by U0126. Conclusion IMD can activate ERK1/2 signaling pathway of BMSCs, and can regulate the expression of apoptosis related proteins. Furthermore, it can protect BMSCs from apoptosis induced by H202. Activation of ERK1/2 pathway was involved in the effect of IMD on apoptosis.