Diet composition transiently modulates proliferative and potency features of human cord blood-derived mesenchymal stem cells.

Mesenchymal stem cells (MSC) emerged in the last few years as a promise in regenerative medicine and have been actively tested in several clinical trials worldwide. However, the lack of common standards and a precise definition of MSC preparations remain a major obstacle in research and application. In this study, we compared the effects during culture of two different MSC commercial media (aMEM and SPE-IV) on the proliferative capacities, phenotypic and molecular features in human cord blood derived-MSC lines. Moreover, as miRNA are markers of stem cell multipotency and regulators of somatic cell reprogramming, we performed a miRNome analysis in both conditions. As a result, we observed that SPE-IV promoted a faster growth and modulated stemness and proliferation associated genes such as PDGFRB, p16 and p21. Notably, in aMEM miR-335 and miR-302b, both proposed as putative stemness markers, were upregulated together with miRNAs reported to decrease adipo- and osteogenesis confirming the observed reduced differentiation potential after growth in this condition. Intriguingly, phenotypic divergences were entirely due to culturing conditions and, most importantly, completely transitory since, after medium switch, the cells were able to revert their signatures. Thus, it emerges as crucial keeping constant the experimental settings, starting from culturing conditions, to avoid misleading characterization of stemness and/or potency markers when the eventual goal is unequivocal definition of such parameters for future clinical choice.