血管紧张素Ⅱ预处理提高间充质干细胞耐缺氧能力

AngiotensinⅡ preconditioning prevents mesenchymal stem cells from hypoxic injury

目的:探讨血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)预处理对骨髓间充质干细胞(mesenchymal stem cells,MSCs)耐缺氧能力的影响。方法:分离培养大鼠MSCs,应用CD29、CD11b/c抗体进行细胞鉴定。对细胞以不同浓度AngⅡ预处理3 h,采用缺氧联合无血清(hypoxia/SD)的方法诱导缺氧损伤模型;应用血管紧张素1型受体(AT1)拮抗剂氯沙坦(losartan)、血管紧张素2型受体(AT2)拮抗剂PD123319进行干预。应用MTT和CCK-8法测定细胞活力以确定最佳刺激浓度,采用台盼蓝染色,CCK-8检测和流式细胞术测定各组细胞活力和凋亡率。结果:①MSCs表面抗原CD29阳性率>97%,CD11b/c阳性率<1%;②AngⅡ预处理显著提高MSCs的活力,减少细胞凋亡率;③AngⅡ对MSCs的预适应保护作用呈现一定的浓度依赖性,最佳浓度为10nmol/L;④氯沙坦可抑制AngⅡ的预适应细胞保护作用,而PD123319无此效应。结论:AngⅡ通过AT1受体发挥对MSCs的预适应保护作用。

Objective：To investigate whether Angiotensin II protects mesenchymal stem cells （MSCs） from hypoxic injury. Methods：The MSCs were isolated and cultured,and their purities were identified with the spindle-fibroblastic morphology characterizahon by microphotograph,and the phenotypes were tested by flow cytometry with anti-CD29 and anti-CD1 lb/c antibodies. Before preconditioned by Ang II, the MSCs were treated with or without angiotensin 1 （AT1） receptor antagonist losartan, angiotensin 2 （AT2） receptor antagonist PD123319. Then the cells were suffered from hypoxia and serum deprivation for 24 hours. The cell viability and apoptosis were determined by trypan blue staining, MTY, CCK-8 assay and Annexin V-FITC staining. Results： （1） MSCs expressed CD29,but not the CD1 lb/c. The purity of MSCs employed in this study was up to 97%; （2） Ang II preconditioning （PC） markedly protected MSCs from hypoxic injury. However,these effects were abohshed by prior treatment with losartan rather than PD123319. Conclusion：These results suggest that Ang II preconditioning protects MSCs from hypoxic injury through AT1 receptor.