基质细胞衍生因子1预处理抑制大鼠骨髓间充质干细胞的凋亡

Stromal cell-derived factor-1 preconditioning inhibits apoptosis of rat bone marrow mesenchymal stem cells

背景:研究发现基质细胞衍生因子1除参与趋化干细胞定向迁移途径,还具有抗凋亡作用。目的:观察基质细胞衍生因子1预处理后对骨髓间充质干细胞凋亡的影响。方法:以不同浓度H2O2诱导大鼠骨髓间充质干细胞凋亡,取最适宜浓度100μmol/L用于实验。不同质量浓度基质细胞衍生因子1干预100μmol/L H2O2诱导后的大鼠骨髓间充质干细胞,选择0.2mg/L最佳保护质量浓度用于实验。取第3代大鼠骨髓间充质干细胞,随机分组:正常对照组不进行任何处理;损伤组在培养液中加入H2O2作用24h;基质细胞衍生因子1预处理组于H2O2损伤细胞前6h加入基质细胞衍生因子1;基质细胞衍生因子1+AMD3100(基质细胞衍生因子1受体CXCR4的阻断剂)组于H2O2细胞损伤前6h加入基质细胞衍生因子1与AMD3100共孵。结果与结论:H2O2能体外模拟缺血缺氧环境诱导骨髓间充质干细胞凋亡,且作用呈剂量依赖性。与损伤组比较,加入基质细胞衍生因子1预处理后细胞凋亡明显减轻(P<0.01),细胞E2F6基因表达增强(P<0.05),E2F1基因表达减少(P<0.05),线粒体细胞色素C转位减少(P<0.05),Caspase-3活性降低(P<0.05),AMD3100可阻断基质细胞衍生因子1对骨髓间充质干细胞的保护作用。提示基质细胞衍生因子1可能通过增强E2F6基因,负性调控E2F1基因抑制线粒体损伤导致的骨髓间充质干细胞凋亡。

BACKGROUND：Studies demonstrated that stromal cell-derived factor-1 may participate in anti-apoptosis of mesenchymal stem cells in addition to directed migration. OBJECTIVE：To investigate that stromal cell-derived factor-1 preconditioning inhibits apoptosis of MSCs. METHODS：Apoptosis of rat bone marrow mesenchymal stem cells was induced with different concentrations of H2O2. H2O2 at the optimal concentration of 100 μmol/L was used for experiments. Rat bone marrow mesenchymal stem cells were induced with 100 μmol/L H2O2 and then treated with stromal cell-derived factor-1 at different concentrations, and stromal cell-derived factor-1 at the optimal concentration was used for experiment. Passage 3 rat bone marrow mesenchymal stem cells were randomly divided into four groups. The normal control group was treated with nothing. The injured group was treated with 100 μM H2O2 for 24 hours. The stromal cell-derived factor-1 preconditioning group was treated with stromal cell-derived factor-1 at 6 hours before H2O2 addition. The stromal cell-derived factor-1＋AMD3100 （an antagonist of stromal cell-derived factor-1 receptor CXCR4） group was incubated with stromal cell-derived factor-1 and AMD3100 at 6 hours before H2O2 addition. RESULTS AND CONCLUSION：H2O2 could mimic ischemic environment and induce the apoptosis of bone marrow mesenchymal stem cells in a dose-dependent manner in vitro. After stromal cell-derived factor-1 preconditioning, cell apoptosis was significantly alleviated （P 0.01）, E2F6 and E2F1 mRNA expression was significantly increased （P 0.05）, cytochrome c translocation was significantly reduced （P 0.05）, caspase-3 activity was decreased （P 0.05） compared with the injured group. AMD3100 could block the protective effect of stromal cell-derived factor-1 on bone marrow mesenchymal stem cells. These results suggest that stromal cell-derived factor-1 is capable to reduce the apoptosis of bone marrow mesenchymal stem cells by upregulating E2F6 mRNA expression, negatively regulating E2F1 mRNA expression, and decreasing cytochrome c release.