Hidalgo Alejandro, Glass Nick, Ovchinnikov Dmitry, Yang Seung-Kwon, Zhang Xinli, Mazzone Stuart, Chen Chen, Wolvetang Ernst, Cooper-White Justin
Tissue Engineering and Microfluidics Group, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane 4072, Australia.
Stem Cell Engineering Group, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane 4072, Australia.
APL Bioeng. 2018 Mar 20;2(2):026102. doi: 10.1063/1.5000746. eCollection 2018 Jun.
Coronary intervention following ST-segment elevation myocardial infarction (STEMI) is the treatment of choice for reducing cardiomyocyte death but paradoxically leads to reperfusion injury. Pharmacological post-conditioning is an attractive approach to minimize Ischemia-Reperfusion Injury (IRI), but candidate drugs identified in IRI animal models have performed poorly in human clinical trials, highlighting the need for a cell-based model of IRI. In this work, we show that when we imposed sequential hypoxia and reoxygenation episodes [mimicking the ischemia (I) and reperfusion (R) events] to immature human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs), they display significant hypoxia resistance and minimal cell death (∼5%). Metabolic maturation of hPSC-CMs for 8 days substantially increased their sensitivity to changes in oxygen concentration and led to up to ∼30% cell death post-hypoxia and reoxygenation. To mimic the known transient changes in the interstitial tissue microenvironment during an IRI event , we tested a new IRI model protocol that required glucose availability and lowering of media pH during the ischemic episode, resulting in a significant increase in cell death (∼60%). Finally, we confirm that in this new physiologically matched IRI model, pharmacological post-conditioning reduces reperfusion-induced hPSC-CM cell death by 50%. Our results indicate that in recapitulating key aspects of an IRI event, our model can serve as a useful method for the study of IRI and the validation and screening of human specific pharmacological post-conditioning drug candidates.
ST段抬高型心肌梗死（STEMI）后的冠状动脉介入治疗是减少心肌细胞死亡的首选治疗方法，但矛盾的是会导致再灌注损伤。药物后适应是一种有吸引力的方法，可将缺血再灌注损伤（IRI）降至最低，但在IRI动物模型中确定的候选药物在人体临床试验中表现不佳，这凸显了建立基于细胞的IRI模型的必要性。在这项研究中，我们发现，当我们对未成熟的人多能干细胞衍生的心肌细胞（hPSC-CMs）施加序贯性缺氧和复氧过程（模拟缺血（I）和再灌注（R）事件）时，它们表现出显著的缺氧抗性和最小的细胞死亡（约5%）。hPSC-CMs代谢成熟8天显著增加了它们对氧浓度变化的敏感性，并导致缺氧和复氧后高达约30%的细胞死亡。为了模拟IRI事件期间间质组织微环境中已知的短暂变化，我们测试了一种新的IRI模型方案，该方案要求在缺血期间提供葡萄糖并降低培养基pH值，导致细胞死亡显著增加（约60%）。最后，我们证实，在这个新的生理匹配的IRI模型中，药物后适应可使再灌注诱导的hPSC-CM细胞死亡减少50%。我们的结果表明，在概括IRI事件的关键方面时，我们的模型可作为研究IRI以及验证和筛选人类特异性药物后适应候选药物的有用方法。
