Chitosan-PVA-CNT nanofibers as electrically conductive scaffolds for cardiovascular tissue engineering.

Conductive scaffolds are suitable candidates for cardiovascular tissue engineering (CTE) due to their similarity to the extracellular matrix of native tissue. Here, nanofiber scaffolds based on polyvinyl alcohol (PVA), chitosan (CS), and different concentrations of carbon nanotube (CNT) were produced using electrospinning. Scanning electron microscopy (SEM) image, mechanical test (elastic modulus: 130 ± 3.605 MPa), electrical conductivity (3.4 × 10-6 S/Cm), water uptake, cell adhesion, and cell viability (>80%) results of the PVA-CS-CNT1 scaffold revealed that the nanofiber containing 1% of CNT has optimal properties for cardiac differentiation. Afterwards, the differentiation of rat mesenchymal stem cells (MSCs) to cardiomyocytes was performed on the optimal scaffold by electrical stimulation in the presence of 5-azacytidine, TGF-β and ascorbic acid. The real-time qPCR results indicated that the expression of Nkx2.5, Troponin I, and β-MHC cardiac marker was increased significantly (>3 folds) in comparison to control group. Based on the findings of this study, the incorporation of MSCs, conductive scaffolds, and electrical stimulation seem to be a promising approach in CTE.