Abstract 543: The Metabolites of Human Cardiac Precursors Enhanced Cardiomyogenic Differentiation of hiPSC

Abstract

Background: Wnt signaling pathways are involved in cardiomyogenic differentiation. Besides that, nutrients and metabolism may also influence cell differentiation. However, it is still unclear whether the cell lineage commitment could be controlled by the metabolites of its precursor cells. The aim of this study is to examine whether the metabolites of cardiac precursors could determine cardiomyogenic differentiation fate of hiPSC. Methods: hiPSC was maintained in serum-free and feeder-free monolayer condition. After CHIR99021-induced mesendodermal differentiation for two days, IWP4 was added to inhibit Wnt signaling and to induce myogenic differentiation for another two days. After wash, the culture medium was collected during cell differentiation period of day 5-10 (d5-10-diff-medium). ExoQuick-TC kit was used to extract the exosomes in the medium. Cardiomyocytes were identified by immunocytochemistry staining with mouse monoclonal antibody against cardiac sarcomeric actinin alpha, and were counted the percentage by flow cytometry. Results: The exosome-free d5-10-diff-medium was found to be able to dramatically induce cardiomyogenic differentiation only in CHIR99021-induced mesendodermal cells, rather than directly in hiPSC, in the absence of Wnt inhibitor. The metabolic profiling of the exosome-free d5-10-diff-medium was further characterized by LC-MS. After functional validation, the effective metabolites for the induction of cardiomyogenic differentiation were identified and the possible signaling pathways were analyzed. Conclusion: This study demonstrated that the metabolites of cardiac precursors could control cardiac cell commitment by driving the development of cardiac metabolic system.