Role of human cardiac biopsy derived conditioned media in modulating bone marrow derived mesenchymal stem cells toward cardiomyocyte-like cells

Background: Mesenchymal stem cells (MSCs) are multipotent and can be easily cultured and expanded. Therefore, these are considered to be an attractive therapeutic tool for cardiac repair. These have been found to have tremendous potential to transdifferentiate to cardiac lineage both in vitro and in vivo. A number of chemicals and growth factors have been explored for the same. However, the effect of the paracrine factors released by cardiac tissue has not been studied much. Materials and Methods: In the present study, we have examined the differentiation capacity of conditioned media (CM) derived from human cardiac tissue on human bone marrow-derived MSCs (BM-MSCs). BM-MSCs after characterization were induced by culture supernatant collected from human cardiac tissue (21 days). Parallel cultures treated with 5-azacytidine (AZA) (30 days), were taken as controls. Results: MSCs treated with CM formed “muscle island” like structure and were found to be positive for cardiac-specific markers - myosin light chain-2v and cardiac troponin I proteins. However, uninduced BM-MSCs did not show positivity for any of these markers and maintained fibroblastic morphology. Conclusion: These findings demonstrate that cardiac CM is capable of effective induction of morphological and molecular changes in MSCs toward cardiac features. However, differentiation efficiency is less than that of 5-AZA and the mode of action and the components of CM are still to be known