Intermittent Starvation Promotes Maturation of Human Embryonic Stem Cell-Derived Cardiomyocytes
Jingsi Yang1, Nan Ding1, Dandan Zhao1
1Department of Cardiovascular Surgery of the First Affiliated Hospital & Institute for Cardiovascular Science, Collaborative Innovation Center of Hematology, State Key Laboratory of Radiation Medicine and Protection, Medical College, Soochow University, Suzhou, China.
Insights
Intermittent starvation using Earle's balanced salt solution (EBSS) effectively matures human embryonic stem cell-derived cardiomyocytes (hESC-CMs) in structure, metabolism, and electrophysiology, overcoming limitations in cardiovascular research.
Area of Science:
- Cardiovascular Biology
- Stem Cell Biology
- Cellular Metabolism
Background:
- Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) are crucial for cardiovascular disease research but exhibit immature phenotypes.
- Current in vitro maturation methods for hPSC-CMs are insufficient for fully adult-like properties.
- Cardiomyocyte maturation involves a critical prenatal-to-postnatal transition characterized by nutrient starvation and autophagy.
Purpose of the Study:
- To develop an in vitro strategy mimicking in vivo starvation to promote hPSC-CM maturation.
- To investigate the effects of Earle's balanced salt solution (EBSS) treatment on cardiomyocyte maturation.
Main Methods:
- Developed a novel intermittent starvation protocol using EBSS treatment for human embryonic stem cell-derived cardiomyocytes (hESC-CMs).
- Applied 2-hour EBSS treatment daily for 10 days to mimic in vivo starvation events.
- Assessed structural, metabolic, and electrophysiological maturation markers post-treatment.
Main Results:
- EBSS-induced starvation activated autophagy and mitophagy in hESC-CMs.
- Intermittent starvation significantly improved structural maturation, including increased cell size and organized cytoskeleton.
- Metabolic maturation was enhanced, evidenced by increased mitochondrial content and oxidative phosphorylation.
- Electrophysiological maturation improved, indicated by longer action potential duration and enhanced calcium handling.
Conclusions:
- EBSS-induced intermittent starvation is a simple and effective method for promoting hESC-CM maturation.
- This approach addresses key limitations in hPSC-CM structure, metabolism, and electrophysiology.
- The findings offer a cost-effective strategy for advancing cardiovascular disease modeling and therapy.
Abstract:
Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) represent an infinite cell source for cardiovascular disease modeling, drug screening and cell therapy. Despite extensive efforts, current approaches have failed to generate hPSC-CMs with fully adult-like phenotypes in vitro, and the immature properties of hPSC-CMs in structure, metabolism and electrophysiology have long been impeding their basic and clinical applications. The prenatal-to-postnatal transition, accompanied by severe nutrient starvation and autophagosome formation in the heart, is believed to be a critical window for cardiomyocyte maturation. In this study, we developed a new strategy, mimicking the in vivo starvation event by Earle's balanced salt solution (EBSS) treatment, to promote hPSC-CM maturation in vitro. We found that EBSS-induced starvation obviously activated autophagy and mitophagy in human embryonic stem cell-derived cardiomyocytes (hESC-CMs). Intermittent starvation, via 2-h EBSS treatment per day for 10 days, significantly promoted the structural, metabolic and electrophysiological maturation of hESC-CMs. Structurally, the EBSS-treated hESC-CMs showed a larger cell size, more organized contractile cytoskeleton, higher ratio of multinucleation, and significantly increased expression of structure makers of cardiomyocytes. Metabolically, EBSS-induced starvation increased the mitochondrial content in hESC-CMs and promoted their capability of oxidative phosphorylation. Functionally, EBSS-induced starvation strengthened electrophysiological maturation, as indicated by the increased action potential duration at 90% and 50% repolarization and the calcium handling capacity. In conclusion, our data indicate that EBSS intermittent starvation is a simple and efficient approach to promote hESC-CM maturation in structure, metabolism and electrophysiology at an affordable time and cost.
