Keung, WendyRen, LihuanSen LiWong, Andy On-TikChopra, AnantKong, Chi-WingTomaselli, Gordon F.Chen, ChristopherLi, Ronald A.2016-11-182016Keung, Wendy, Lihuan Ren, Sen LiAndy On-Tik Wong, Anant Chopra, Chi-Wing Kong, Gordon F. Tomaselli, Christopher S. Chen, and Ronald A. Li. 2016. “Non-cell autonomous cues for enhanced functionality of human embryonic stem cell-derived cardiomyocytes via maturation of sarcolemmal and mitochondrial KATP channels.” Scientific Reports 6 (1): 34154. doi:10.1038/srep34154. http://dx.doi.org/10.1038/srep34154.2045-2322http://nrs.harvard.edu/urn-3:HUL.InstRepos:29407700Human embryonic stem cells (hESCs) is a potential unlimited ex vivo source of ventricular (V) cardiomyocytes (CMs), but hESC-VCMs and their engineered tissues display immature traits. In adult VCMs, sarcolemmal (sarc) and mitochondrial (mito) ATP-sensitive potassium (KATP) channels play crucial roles in excitability and cardioprotection. In this study, we aim to investigate the biological roles and use of sarcKATP and mitoKATP in hESC-VCM. We showed that SarcIK, ATP in single hESC-VCMs was dormant under baseline conditions, but became markedly activated by cyanide (CN) or the known opener P1075 with a current density that was ~8-fold smaller than adult; These effects were reversible upon washout or the addition of GLI or HMR1098. Interestingly, sarcIK, ATP displayed a ~3-fold increase after treatment with hypoxia (5% O2). MitoIK, ATP was absent in hESC-VCMs. However, the thyroid hormone T3 up-regulated mitoIK, ATP, conferring diazoxide protective effect on T3-treated hESC-VCMs. When assessed using a multi-cellular engineered 3D ventricular cardiac micro-tissue (hvCMT) system, T3 substantially enhanced the developed tension by 3-folds. Diazoxide also attenuated the decrease in contractility induced by simulated ischemia (1% O2). We conclude that hypoxia and T3 enhance the functionality of hESC-VCMs and their engineered tissues by selectively acting on sarc and mitoIK, ATP.en-USJournal Article2016-11-1810.1038/srep34154