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bioRxiv · 10.1101/2020.03.19.998344

Angiotensin II induces apoptosis in human induced pluripotent stem cell-derived cardiomyocytes

Gao, Q.·Wang, P.·Wu, Z.·Qiu, H.·Lin, B.·Chen, J.·Cen, J.·Zhuang, J.
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Abstract

BackgroundThe renin-angiotensin system (RAS) functions fundamentally to regulate the pathological process of cardiovascular diseases, such as heart failure and hypertension. As the major effector in RAS, angiotensin II activates angiotensin II receptors to initiate the downstream pathways, which lead to the phenotypes including apoptosis, hypertrophy, and cardiac remodeling. Human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) are being applied as a promising platform for personalized medicine to heart diseases. However, whether angiotensin II induces apoptosis in iPSC-CM is still obscure, which raises an uncertainty about the clinical applications of iPSC-CM. MethodsWe treated iPSC-CM with angiotensin II at eight concentrations (0 nM, 1 nM, 10 nM, 100 nM, 1 M, 10 M, 100 M and 1 mM) and four incubation durations (24 hours, 48 hours, 6 days and 10 days), then PrestoBlue reagent and a apoptosis marker were used to examine the viability and apoptosis status of cardiomyocytes from each group. The expression levels of some apoptosis and proliferation related genes were also analyzed. ResultsHigh concentration angiotensin II with a long-term treatment caused apoptosis and cell viability drop-off in iPSC-CM. Specifically, under a 10-day treatment with 1 mM angiotensin II, the viability of iPSC-CM was reduced by an average of 41% (p=2.073E-08), and the percentage of apoptotic cells was 2.74 times higher than the controls averagely (p=6.248E-12). The data mining of previous RNA-seq data revealed that angiotensin II receptor type I was the major receptor in iPSC-CM. Conclusions: For the first time, our data confirmed the apoptotic effect of angiotensin II to iPSC-CM. The angiotensin II concentrations and exposure time for apoptosis induction were depicted in our study, which provided supports to iPSC-CM as an in vitro model for cardiovascular disease study.

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Gao, Q., Wang, P., Wu, Z., Qiu, H., Lin, B., Chen, J., Cen, J., Zhuang, J.. 2020-03-20. Angiotensin II induces apoptosis in human induced pluripotent stem cell-derived cardiomyocytes. https://doi.org/10.1101/2020.03.19.998344

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