International Journal of Stem Cells : eISSN 2005-5447

Table. 1.

Table. 1.

Hallmarks of cardiac maturation

Characteristics Functional assessments Key references
Structure Myofibrils massive expansion Sarcomere length (14-17, 20, 23, 26)
More clear banding Fractional shortening
Improved sarcomere filament alignment Contraction velocity
M-line more clear
Sarcomeric isoform switching
Metabolism Increased number and size of mitochondria Oxygen consumption rate (47-50, 52, 53, 56)
Densely organized cristae Mitochondrial membrane polarization
Mitochondrial membrane polarization
Glycolytic genes downregulation
Calcium handling & electrophysiology More negative resting membrane potential Calcium transient (66-72, 76, 79)
Longer plateau phase of action potential Peak height
Faster upstroke velocity Departure velocity
T-tubulea formation Action potential
Low automaticity
Cardiomyocyte proliferation Decreased proliferation rate Brdub (84-89, 91-95, 97)
Repressed cell cycle regulators Ki67
Maturational hypertrophy pH3c
Polyploidization

aT-tubule: transverse tubules, bBrdu: 5-bromodeoxyuridine, cpH3: phosphorylated histone H3.

International Journal of Stem Cells 2021;14:366-85 https://doi.org/10.15283/ijsc21077
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