Increased cardiomyocyte alignment and intracellular calcium transients using micropatterned and drug-releasing poly(glycerol sebacate) elastomers

Myocardial tissue engineering is a promising therapy for myocardial infarction recovery. The success of myocardial tissue engineering is likely to rely on the combination of cardiomyocytes, pro-survival regulatory signals, and a flexible biomaterial structure that can deliver them. In this study, poly (glycerol sebacate) (PGS), which exhibits stable elasticity under repeated tensile loading, was engineered to provide physical features that aligned cardiomyocytes in a similar manner to that seen in native cardiac tissue. In addition, a small molecule mimetic of brain derived neurotrophic factor (BDNF) was polymerised into the PGS to achieve a continuous and steady release. Micropatterning of PGS elastomers increased cell alignment, calcium transient homogeneity and cell connectivity. The intensity of the calcium transients in cardiomyocytes was enhanced when cultured on PGS which released a small molecule BDNF mimetic. This study demonstrates that robust micropatterned elastomer films are a potential candidate for the delivery of functional cardiomyocytes and factors to the injured or dysfunctional myocardium, as well as providing novel in vitro platforms to study cardiomyocyte physiology.