Previous studies have shown that the differentiation potential declines with the age of progenitor cells and is linked to altered levels of senescence markers. The purpose of this study was to test whether senescence marker p16 affects age-related tenogenic differentiation in tendon stem/progenitor cells (TSPCs). Young and aged TSPCs were isolated from young/healthy and aged/degenerated human Achilles tendons, respectively. Cellular aging and capacity for tenogenic differentiation were examined. The results showed that the tenogenic differentiation capacity of TSPCs significantly decreases with advancing age. TSPCs from elderly donors showed upregulation of senescence-associated β-galactosidase and p16 and concurrently a decrease in Type I collagen concentration and in the expressions of tendon-related markers: Scx, Tnmd, Bgn, Dcn, Col1, and Col3. Overexpression of p16 significantly inhibited tenogenic differentiation of young TSPCs. Analysis of the mechanism revealed that this effect is mediated by microRNA-217 and its target EGR1. These results indicated that p16 inhibits tenogenic differentiation of TSPCs via microRNA signaling pathways, which may serve as a potential target for the prevention or treatment in the future.
Keywords: aging; miR-217; p16; progenitor cell; tendon stem.
© The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: [email protected].