Department of Cardiology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China.
Biochem Biophys Res Commun. 2013 Feb 15;431(3):566-71. doi: 10.1016/j.bbrc.2013.01.015. Epub 2013 Jan 11.
Cardiac progenitors (CPC) mediate cardioprotection via paracrine effects. To date, most of studies focused on secreted paracrine proteins. Here we investigated the CPC-derived-exosomes on protecting myocardium from acute ischemia/reperfusion (MI/R) injury.
CPC were isolated from mouse heart using two-step protocol. Exosomes were purified from conditional medium, and confirmed by electron micrograph and Western blot using CD63 as a marker. qRT-PCR shows that CPC-exosomes have high level expression of GATA4-responsive-miR-451. Exosomes were ex vivo labeled with PKH26, We observed exosomes can be uptaken by H9C2 cardiomyoblasts with high efficiency after 12 h incubation. CPC-exosomes protect H9C2 from oxidative stress by inhibiting caspase 3/7 activation invitro. In vivo delivery of CPC-exosomes in an acute mouse myocardial ischemia/reperfusion model inhibited cardiomyocyte apoptosis by about 53% in comparison with PBS control (p<0.05).
Our results suggest, for the first time, the CPC-exosomes can be used as a therapeutic vehicle for cardioprotection, and highlights a new perspective for using non-cell exosomes for cardiac disease.
心脏祖细胞（CPC）通过旁分泌作用介导心脏保护。迄今为止，大多数研究都集中在分泌的旁分泌蛋白上。在这里，我们研究了 CPC 衍生的外泌体对急性缺血/再灌注（MI/R）损伤心肌的保护作用。
采用两步法从鼠心中分离 CPC。用超速离心法从条件培养基中纯化外泌体，并通过电子显微镜和 CD63 作为标记物的 Western blot 进行确认。qRT-PCR 显示 CPC 外泌体具有高表达的 GATA4 反应性 miR-451。用 PKH26 对 exosomes 进行体外标记，我们观察到 exosomes 在孵育 12 小时后可被 H9C2 心肌细胞高效摄取。CPC 外泌体通过抑制体外 caspase 3/7 激活来保护 H9C2 免受氧化应激。与 PBS 对照组相比（p<0.05），在急性小鼠心肌缺血/再灌注模型中递送 CPC 外泌体可使心肌细胞凋亡减少约 53%。
我们的研究结果首次表明，CPC 外泌体可用作心脏保护的治疗载体，并为使用非细胞外泌体治疗心脏疾病提供了新视角。
