Fig. 6

Osteogenic and chondrogenic potentials of muscle- and bone-derived MSCs. Culture-expanded cells were tested for osteogenic (a, b) and chondrogenic (c, d) potentials. Alizarin Red S staining (a) and osteogenic genes (b) were measured to assess osteogenesis. Muscle-derived MSCs from OA patients showed significantly lower Alizarin Red S concentrations (0.302 vs. 1.33 mg/mL, p = 0.007). Bone-derived MSCs from OA patients showed significantly lower Alizarin Red S concentrations compared to MSCs from OP patients and controls (0.04386 vs. 0.5329 and 0.9433 mg/mL, p = 0.033 and 0.003, respectively) (a). Toluidine blue and collagen type II (Col2A1) staining (c), Bern score (d, left), and pellet diameter (d, right) measurements were performed to assess chondrogenesis. Representative images of toluidine blue-stained chondrogenic pellets are shown (c, right). Scale bars: 200 μm