Abstract
Background: Due to its low capacity for self-repair, articular cartilage is highly susceptible to damage and deterioration, which leads to the development of degenerative joint diseases such as osteoarthritis. Menstrual blood-derived mesenchymal stem cells (MenSCs) are much less characterized compared to bone marrow mesenchymal stem cells (BMMSCs). However, MenSCs seem an attractive alternative to classical BMMSCs due to ease of access and broader differentiation capacity. The aim of this study was to evaluate chondrogenic differentiation potential of MenSCs and BMMSCs stimulated with transforming growth factor β (TGF-β3) and activin A, member of the TGF-β superfamily of proteins.Methods: MenSCs (n=6) and BMMSCs (n=5) were isolated from different healthy donors. Expression of cell surface markers CD90, CD73, CD105, CD44, CD45, CD14, CD36, CD55, CD54, CD63, CD106, CD34, CD10, Notch1 was analysed by flow cytometry. Cell proliferation capacity was determined using CCK-8 proliferation kit. Adipogenic differentiation capacity was evaluated according to Oil-Red staining, osteogenic differentiation - Alizarin Red staining. Chondrogenic differentiation (Activin A and TGF-β3 stimulation) was induced in vitro and in vivo (subcutaneous scaffolds in nude BALB/c mice) and investigated by histologically and by expression of chondrogenic genes (collagen type II, aggrecan). Activin A protein production was evaluated by ELISA.Results: MenSCs exhibited a higher proliferation rate, as compared to BMMSCs, and a different expression profile of several cell surface markers. Activin A stimulated collagen type II gene expression and glycosaminoglycan synthesis in TGF-β3 treated MenSCs but not in BMMSCs, both in vitro and in vivo, although the effects of TGF-β3 alone were more pronounced in BMMSCs in vitro. Conclusion: These data suggest that activin A exerts differential effects on the induction of chondrogenic differentiation in MenSCs vs. BMMSCs, which implies that different mechanisms of chondrogenic regulation are activated in these cells. Following further optimisation of differentiation protocols and the choice of growth factors, potentially including activin A, MenSCs may turn out to be a promising population of stem cells for the development of cell-based therapies with the capacity to stimulate cartilage repair and regeneration.Trial registration: Not applicable.
Activin a promotes myofibroblast differentiation of endometrial mesenchymal stem cells via STAT3-dependent Smad/CTGF pathway