溶血磷脂酸抗缺氧无血清诱导的大鼠骨髓间充质干细胞凋亡作用

Lysophosphatidic Acid Protects Mesenchymal Stem Cells against Hypoxia and Serum Deprivation-induced Apoptosis

在体外缺氧无血清条件下模拟心肌缺血微环境,研究溶血磷脂酸(LPA)对骨髓间充质干细胞(BMMSCs)的抗凋亡作用。应用Hoechst33342染色和膜联蛋白V/PI双染流式细胞术观察细胞凋亡,并利用Western印迹方法检测ERK1/2和Akt的磷酸化水平变化。结果表明缺氧无血清条件引起明显的细胞凋亡,LPA处理6h和1+6h组细胞凋亡率较缺氧无血清组显著降低(P<0.05),而1h组细胞凋亡率与缺氧无血清组无显著性差异。LPA处理组(1h,6h,1+6h组)ERK1/2磷酸化水平较缺氧无血清组降低,Akt磷酸化水平较缺氧无血清组增高。在缺氧无血清环境中,LPA有利于增强BMMSCs的抗凋亡能力,提高BMMSCs存活率,为临床提高BMMSCs治疗缺血性心肌病的疗效提供理论依据。

The aim of this study is to investigate the effects of lysophosphatidic acid （LPA） on the apoptosis of bone marrow-derived mesenchymal stem cells （BMMSCs）. The apoptosis was detected by Hoechst33342 staining and annexin V/PI dual-color flow cytometry, and the expression of signaling proteins was evaluated by Western blot analysis. In the condition of hypoxia and serum deprivation （hypoxia/SD）, a significant apoptosis occurred in BMMSCs. The groups of LPA 6 h or LPA 1＋6 h, but not LPA 1 h, significantly decreased the apoptosis induced by hypoxia/SD （P〈0.05）. The effect of LPA on the intracellular signal pathways was also examined. Akt was activated, while ERK1/2 was depressed by LPA under hypoxia/SD conditions. These results suggest LPA could decrease the apoptosis of BMMSCs induced by hypoxia/SD, and increase the survival of BMMSCs.