来自缺血肌肉的微粒子促进产后血管生成
Aurelie S Leroyer1, Téni G Ebrahimian, Clément Cochain
1Paris Cardiovascular Research Center, INSERM U, Hôpital Européen Georges Pompidou, Université Paris-Descartes, France.
Circulation
|May 20, 2009
概括
组织缺血期间释放的微粒子通过刺激原始细胞分化来促进新血管的形成. 这些发现突显了微粒在后缺血性血管生成中的作用.
科学领域:
- 生物医学科学 生物医学科学
- 细胞生物学 细胞生物学
- 血管生物学 血管生物学
背景情况:
- 微粒 (MPs) 在组织缺血期间释放.
- 假设这些MP是驱动后缺血性血管生成的内源信号.
研究的目的:
- 为了研究微粒在后缺血性血管生成中的作用.
- 为了确定来自缺血组织的MP是否会刺激原始细胞分化并促进再血管化.
主要方法:
- 从缺血性小鼠后肢肌肉中用顺序离心法分离了MPs.
- 流细胞计和电子显微镜用于MP的表征.
- 在体外测试中评估了MP诱导的骨髓单核细胞 (BM-MNC) 分化.
- 在体内研究中,评估了MPs在小鼠后肢模型中对缺血后再血管化的影响.
主要成果:
- 来自缺血肌的MPs显著增加,主要来自内皮细胞.
- 缺血性MPs在体外增强了BM-MNC分化到内皮细胞.
- 来自缺血性肌肉的MPs显示NADPH氧化酶子单元的表达增加 (p47,p67).
- MP注射改善了缺血性后肢的BM-MNC介导的重血管化,这种效果取决于gp91的表达.
结论:
- 组织缺血期间产生的微粒是原始细胞分化的强有力的刺激剂.
- 这些MP在促进缺血后产后新血管化的过程中发挥着至关重要的作用.
- 这些发现阐明了一种在缺血事件后内源性修复的新机制.
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