Fig. 3

The effect of OAS-CM on mechanically mediated activation of Smad3P-responsive genes in bovine articular cartilage. The influence of 3 and 12 MPa dynamic mechanical compression, carried out with OAS-CM (squares) or without (dots), on relative expression of bSerpine1 (a), bSmad7 (b), bJunb (c), and bTgfb1 (d). Dynamic mechanical compression with 3 as well as with 12 MPa potently upregulated bSerpine1, bSmad7, bJunb, and bTgfb1 in conditions without OAS-CM. In unloaded controls treated with OAS-CM, a significant bSerpine1, bSmad7, and bJunb upregulation was observed. Regardless of this issue, in the presence of OAS-CM a mechanically mediated upregulation of bSerpine1, Smad7, JunB, and bTgfb1 was noticed. Nevertheless, in the presence of OAS-CM, the 3 MPa compression-mediated upregulation of bSmad7 and bTgfb1 was significantly lower than the effect of 3 MPa in conditions without OAS-CM. The effect of compression in the presence of OAS-CM was comparable to the effect of exogenous TGF-β1 stimulation in the presence of OAS-CM. Data are expressed as a grouped column scatter of multiple repeats with displayed mean (each point represents individual experimental repeat on material isolated from a different animal, N = 4). ^* p ≤ 0.05; ^** p ≤ 0.01; ^*** p ≤ 0.001. CTR control, GAPDH glyceraldehyde 3-phosphate dehydrogenase, OAS-CM osteoarthritic synovium-conditioned medium, TGF-β transforming growth factor beta