TCA cycle intermediates as an adjunct strategy for human iPSC-derived cardiomyocyte maturation

Area of Science:

• Cardiology
• Stem Cell Biology
• Metabolic Engineering

Background:

• Human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) are crucial for cardiac disease modeling and drug discovery.
• The immature phenotype of iPSC-CM limits their application, as maturation involves a shift from glycolysis to oxidative phosphorylation.
• Tricarboxylic acid (TCA) cycle activity is vital for energy production during cardiomyocyte maturation, but TCA cycle intermediates are low in iPSC-CM.

Purpose of the Study:

• To investigate the effect of supplementing iPSC-CM with TCA cycle intermediates on their maturation.
• To evaluate the impact of TCA cycle intermediates on energy metabolism, cellular function, and gene expression in iPSC-CM.

Main Methods:

• iPSC-CM were cultured in glucose (Glu), galactose (Gal), or galactose plus TCA cycle intermediates (Gal+TCA).
• Evaluated calcium handling, cellular morphology, electrical activity, and mitochondrial health.
• Assessed gene expression related to cardiomyocyte maturation and fetal markers.

Main Results:

• Supplementation with TCA cycle intermediates improved calcium handling, cellular morphology, electrical activity, and mitochondrial health in iPSC-CM.
• Gal+TCA treatment promoted a shift towards oxidative phosphorylation and upregulated cardiomyocyte maturation genes while downregulating fetal genes.
• Benefits were evident compared to glucose alone, though modest compared to galactose supplementation alone.

Conclusions:

• TCA cycle intermediates supplementation can serve as an adjunct strategy to promote iPSC-CM maturation.
• Enhancing TCA cycle activity is a viable approach to improve the functional and molecular characteristics of iPSC-CM.
• This finding supports the development of improved protocols for generating mature iPSC-CM for therapeutic and research applications.