ABSTRACTThe cardiac cells generation via stem cells differentiation is a promising approach to restore the myocardial infarction. Promoted by our primary bioinformatics analysis as well as some previously published data on potential role of hsa‐miR‐590‐3p in cardiogenesis, we have tried to decipher the role of miR‐590‐5p during the course of differentiation of cardiosphere‐derived cells (CDCs). The differentiation induction of CDCs by TGFB1 was confirmed by real‐time PCR, ICC, and flow cytometry. The expression pattern of hsa‐miR‐590‐5p and some related genes were examined during the differentiation process. In order to study the role of miR‐590‐5p in cardiac differentiation, the effect of miR‐590 overexpression in CDCs was studied. Evaluating the expression patterns of miR‐590 and its potential targets (TGFBRs) during the course of differentiation, demonstrated a significant downregulation of miR‐590 and an upregulation of TGFBR2, following the treatment of CDCs with TGFB1. Therefore, we proposed a model in which TGFB1 exerts its differentiation induction via downregulation of miR‐590, and hence the higher transcriptional expression level of TGFBR2. In accordance with our proposed model, transfection of CDCs by a pLenti‐III‐hsa‐mir‐590‐GFP expression vector before or after the first TGFB1 treatment caused a significant alteration in the expression levels of TGFBRs. Moreover, our data revealed that overexpression of miR‐590 before TGFB1 induction was able to attenuate the CDCs differentiation probably via the reduction of TGFBR2 expression level. Altogether, our data suggest an inhibitory role of miR‐590 during the cardiac differentiation of CDCs which its suppression might elevate the rate of differentiation. J. Cell. Biochem. 116: 179–191, 2015. © 2014 Wiley Periodicals, Inc.