A novel conductive poly (sorbitol sebacate)/polyaniline film to promote cardiomyogenic differentiation of mesenchymal stem cells under electrical stimulation

Abstract

Following myocardial infarction (MI), excessive death of cardiomyocytes that cannot be appropriately replaced leads to considerable decreases in the reparative ability of the myocardium, thereby impairing cardiac performance. Developing electroconductive and durable cardiac patches as stem cell carrier substrates could provide functional therapeutic ability for MI hearts, including restraining the infarcted region to prevent ventricular dilatation and thinning, reforming the internal electrical connection to boost cell-cell communication, and delivering exogenous repair cells to the infarcted tissue to induce angiogenesis, release cytokines, and improve native cell survival, consequently promoting new myocardium formation. In this study, polyaniline (PANi) was doped with camphorsulfonic acid to form dPANi. Poly (sorbitol sebacate) (PSS) prepolymers were then synthesized and blended with different proportions of dPANi to fabricate electrically conductive thin films via the solvent casting method. Several experiments were conducted to determine the mechanical, physical, and biological properties of these composites. Our findings indicate that a film fabricated by uniform distribution of dPANi at a ratio of 3 % w/v into PSS networks (PP3%) exhibited durable tensile properties, acceptable conductivity, ideal wettability, gradual degradation behavior, and good interaction with human umbilical cord mesenchymal stem cells (HUC-MSCs). Additionally, the individual and combined effects of scaffold material composition on the cardiomyogenic differentiation of HUC-MSCs in response to electrical stimulation were investigated by evaluating the expression levels of cardiac-related markers. PP3% alone could not induce cardiomyogenic differentiation; however, in response to electrical stimulation, cardiac-related markers were overexpressed at the transcriptional and protein levels compared to those cultured on PSS. These results suggest a potential conductive cardiac patch for MI repair.