Figure 3
Loss of Sod2 in chondrocytes exacerbates cartilage degeneration during aging.
(a) Quantification of superoxide generation in tibial articular chondrocytes of Sod2 cKO mice at 10 weeks of age using flow cytometry with DHE staining. Error bars show the mean ± s.d. (n = 5, *P < 0.05 versus sham, Student’s t-test). (b) Body weight of control and Sod2 cKO male mice at 12 month of age. Values are the mean ± s.d. (n = 6, n.s., not significant versus control mice, Student’s t-test). (c) Locomotive activity of control and Sod2 cKO male mice at 12 months of age. The right graph indicates the quantification of locomotive activity in control littermates (Sod2fl/fl) and Sod2 cKO mice. Values are the mean ± s.e.m. (n = 6, n.s., not significant versus control mice, Student’s t-test). (d) Cartilage degeneration in safranin O/Fast Green stained sections of the medial region of knee joints from control littermates and Sod2 cKO mice at 12 months of age. Yellow arrowheads indicate the vertical cleft region. The right upper graph indicates the quantification of cartilage degeneration in the medial region, including the medial femoral condyle (MFC) + medial tibial plateau (MTP) of the knee joint; the right middle graph indicates the quantification of cartilage degeneration in MFC; and the right lower graph indicates the quantification of cartilage degeneration in MTP. Scale bars represent, 1 mm. Values are the mean ± s.d. of four mice per group (**P < 0.01, ***P < 0.001 versus control, Student’s t-test).
