Efficient generation of cardiomyocytes from human-induced pluripotent stem cells (hiPSCs) is important for their application in basic and translational studies. Space microgravity can significantly change cell activities and function. Previously, we reported upregulation of genes associated with cardiac proliferation in cardiac progenitors derived from hiPSCs that were exposed to space microgravity for 3 days. Here we investigated the effect of long-term exposure of hiPSC-cardiac progenitors to space microgravity on global gene expression. Cryopreserved 3D hiPSC-cardiac progenitors were sent to the International Space Station (ISS) and cultured for 3 weeks under ISS microgravity and ISS 1 G conditions. RNA-sequencing analyses revealed upregulation of genes associated with cardiac differentiation, proliferation, and cardiac structure/function and downregulation of genes associated with extracellular matrix regulation in the ISS microgravity cultures compared with the ISS 1 G cultures. Gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes mapping identified the upregulation of biological processes, molecular function, cellular components, and pathways associated with cell cycle, cardiac differentiation, and cardiac function. Taking together, these results suggest that space microgravity has a beneficial effect on the differentiation and growth of cardiac progenitors.

从人诱导多能干细胞 (hiPSC) 中高效生成心肌细胞对于其在基础和转化研究中的应用非常重要。太空微重力可以显着改变细胞的活动和功能。此前，我们报道了暴露于太空微重力3天的hiPSC衍生的心脏祖细胞中与心脏增殖相关的基因上调。在这里，我们研究了 hiPSC 心脏祖细胞长期暴露于太空微重力对整体基因表达的影响。冷冻保存的 3D hiPSC 心脏祖细胞被送往国际空间站 (ISS)，并在 ISS 微重力和 ISS 1 G 条件下培养 3 周。 RNA测序分析显示，与ISS 1 G培养物相比，ISS微重力培养物中与心脏分化、增殖和心脏结构/功能相关的基因上调，而与细胞外基质调节相关的基因下调。基因本体分析和京都基因和基因组图谱鉴定了生物过程、分子功能、细胞成分以及与细胞周期、心脏分化和心脏功能相关的途径的上调。综上所述，这些结果表明太空微重力对心脏祖细胞的分化和生长具有有益的影响。