Adipogenic differentiation of human mesenchymal stromal cells is down-regulated by microRNA-369-5p and up-regulated by microRNA-371

Long‐term culture of human mesenchymal stromal cells (MSC) has implications on their proliferation and differentiation potential and we have demonstrated that this is associated with up‐regulation of the five microRNAs miR‐29c, miR‐369‐5p, miR‐371, miR‐499, and let‐7f. In this study, we examined the role of these senescence‐associated microRNAs for cellular aging and differentiation of MSC. Proliferation was reduced upon transfection with miR‐369‐5p, miR‐371, and miR‐499. Adipogenic differentiation was impaired by miR‐369‐5p whereas it was highly increased by miR‐371. This was accompanied by respective gene expression changes of some adipogenic key molecules (adiponectin and fatty acid‐binding protein 4 [FABP4]). Furthermore luciferase reporter assay indicated that FABP4 is a direct target of miR‐369‐5p. Microarray analysis upon adipogenic or osteogenic differentiation revealed down‐regulation of several microRNAs albeit miR‐369‐5p and miR‐371 were not affected. Expression of the de novo DNA methyltransferases DNMT3A and DNMT3B was up‐regulated by transfection of miR‐371 whereas expression of DNMT3A was down‐regulated by miR‐369‐5p. In summary, we identified miR‐369‐5p and miR‐371 as antagonistic up‐stream regulators of adipogenic differentiation and this might be indirectly mediated by epigenetic modifications. J. Cell. Physiol. 226: 2226–2234, 2011. © 2010 Wiley‐Liss, Inc.