Mechanical stretch-induced f-actin reorganization and tenogenic differentiation of human mesenchymal stem cells.

Human bone marrow mesenchymal stem cells (hMSCs) are multipotent adult stem cells which are capable of diverse lineages commitment and are considered as a promising cell source for various tissue repair and regeneration. It is well known that mechanical stimuli regulate the biological functions of hMSCs. The purpose of this paper is to investigate the effect of mechanical stretch on cytoskeleton reorganization, gene and protein expressions of differentiation-related markers. Our findings showed that mechanical stretch induced f-actin reorganization, promoted the gene expressions of tendon-related markers including collagen type I (Col I), collagen type III (Col III), tenascin-C (TNC) and scleraxis (SCX), and decreased the gene expressions of collagen type II (Col II) and MSC-protein (MSC-p). Our studies also manifested that the protein expressions of Col I and TNC were increased, and the protein expression of Runx2 was inhibited by mechanical stretch. These results indicate that mechanical stretch may trigger the differentiation of hMSCs into tenocytes. This work provides novel insights into the differentiation of tenogenesis in a strain-induced environment and supports the therapeutic potential of hMSCs. [ABSTRACT FROM AUTHOR]