Effect of miR-195 inhibition on human skeletal muscle-derived stem/progenitor cells.

BACKGROUND Application of a circulating miR-195 inhibitor could be a helping factor in in vitro model of human skeletal muscle- derived stem/progenitor cells (SkMDS/PCs). Previously, miR-195 expression has been reported to be a negative factor for myogenesis. AIMS The aim of the study was to obtain anti-apoptotic and anti-aging effects in in vitro cultured myoblasts and to improve their ability to form myotubes by suppressing miR-195 expression. METHODS Human wild-type (WT) SkMDS/PC cells incubated with control (nonspecific) miRNA inhibitor and miR-195-inhibited SkMDS/PCs were studied. Functional assays (myotube formation and cell ageing), antioxidant, and myogenic gene expression analyses were performed at two time points, at the 7th and 11th cell passages. RESULTS Myotube formation was found to be almost 2-fold higher in the miR-195-inhibited SkMDS/PCs population (p<0.05) compared to WT cells. miR-195 inhibition did not appear to affect cell ageing or rejuvenate human SkMDS/PCs. Antioxidant (SOD3 and FOXO) gene expression was augmented in the miR-195-inhibited SkMDS/PCs population, but no positive effect on the remaining antioxidant genes (SOD1, SOD2, and catalase) was observed. A significant increase in MyoD gene expression with a concomitant decrease in MyoG (p<0.05) was further documented in miR-195-inhibited SkMDS/PCs compared to WT cells (11th cell passage). CONCLUSIONS The performed studies may lead to the preconditioning of myogenic stem cells to extend their potential for pro-regenerative activity. miR-195 inhibitor may serve as conditioning factor augmenting selective antioxidant genes expression and proliferative potential of SkMDS/PCs, but not having an impact on cell aging and/ or apoptosis.