Autologous platelet-rich clot releasate stimulates proliferation and inhibits differentiation of adult rat tendon stem cells towards nontenocyte lineages.

OBJECTIVE

To explore the effects of autologous platelet-rich clot releasate (PRCR) on proliferation and differentiation of adult rat tendon stem cells (TSCs) in vitro, following intense mechanical stretching.

METHODS

TSCs were subjected to 8% mechanical stretching and subsequently incubated in control medium or medium supplemented with 2% or 10% PRCR. Collagen types I and III, peroxisome proliferator-activated receptor-γ (PPARγ), sex determining region Y-box 9 (SOX-9) and runt-related transcription factor 2 (RUNX2) concentrations were assessed via Western blotting and flow cytometry. Transforming growth factor (TGF)-β1 and vascular endothelial growth factor concentrations were measured using enzyme-linked immunosorbent assay. Treated TSCs were also cultured in adipogenic, chondrogenic or osteogenic culture media.

RESULTS

PRCR increased the number of TSCs, and the concentrations of collagen types I and III and TGF-β1. In contrast, PRCR significantly reduced PPARγ, SOX-9 and RUNX2-positive cell numbers, and significantly reduced the numbers of TSC-derived adipocytes, chondrocytes and osteocytes.

CONCLUSION

PRCR induced tenocyte differentiation while suppressing the adipocyte, chondrocyte and osteocyte lineages believed to impede tendon healing.