Fig. 7: PP5 deficiency enhances chondrogenic proliferation in articular cartilage.

Immunohistochemical labeling of growth plates from PP5 KO and WT mice confirmed that phospho- PPARγ (pSER112) was upregulated in KO (d, e, and f), whereas the level of total PPARγ remained unchanged (a, b, and c). In addition, Runx2 expression was markedly increased in PP5 KO (g, h, and i). Further, the levels of cell proliferation marker Ki-67 (j, k, and l) and chondrocyte proliferation-related protein Runx1 (m, n, and o) was increased in the growth plates of PP5 KO mice relative to that of WT (bar = 200 µm). However, Col X (p, q, and r) showed no significant change. Magnified areas are indicated by dashed boxes (bar = 100 µm). Quantitative analyses (c, f, i, l, o, and r) were based on optical density of immunohistochemical staining using NIH ImageJ software. Values are presented as mean ± SE. *P < 0.05, **P < 0.01, and ***P < 0.005 using Student’s t-test. Each genotype, at least five areas of same samples were selected from individual staining and analyses