Small molecule-mediated rapid maturation of iPSC-cardiomyocytes
University Medical Center Utrecht, Utrecht, Netherlands
Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iPSC-CMs) do not display all hallmarks of mature primary cardiomyocytes, especially the ability to use fatty acids (FA) as an energy source, containing high mitochondrial mass, presenting binucleation and increased DNA content per nuclei (polyploidism), and synchronized electrical conduction. This immaturity represents a bottleneck to their application in (1) disease modelling—as most cardiac (genetic) diseases have a middle-age onset—and (2) clinically relevant models, where integration and functional coupling are key. So far, several methods have been reported to enhance iPSC-CM maturation; however, these protocols are laborious, costly, and not easily scalable. Therefore, in this study a simple, low-cost, and rapid protocol to promote cardiomyocyte maturation was developed using two small molecule activators of the peroxisome proliferator-activated receptor β/δ and gamma coactivator 1-alpha (PPAR/PGC-1α) pathway: asiatic acid (AA) and GW501516 (GW). Incubation of monolayers of iPSC-CMs with AA or GW resulting in increased expression of FA metabolism-related genes and markers for mitochondrial activity. AA-treated iPSC-CMs responsiveness to the mitochondrial respiratory chain inhibitors increased and exhibited higher flexibility in substrate utilization. Additionally, structural maturity improved after treatment as demonstrated by an increase in mRNA expression of sarcomeric-related genes and higher nuclear polyploidy in AA-treated samples. Furthermore, treatment led to increased ion channel gene expression and protein levels. Collectively, the authors developed a fast, easy, and economical method to induce iPSC-CMs maturation via PPAR/PGC-1α activation. Treatment with AA or GW led to increased metabolic, structural, functional, and electrophysiological maturation, evaluated using a multiparametric quality assessment.
Small molecule-mediated rapid maturation of human induced pluripotent stem cell-derived cardiomyocytes
Alain van Mil
Added on: 05-02-2023