Fig. 2

VAP modulate ECM synthesis by inhibits MMP13, ADAMTS4 and ADAMTS5 via Wnt /β-catenin signaling pathway. Immunohistochemistry of β-catenin (a) and collagen II (b) were staining in mice facet joint disc. β-catenin was express in chondrcyte (dark brown) and collagen II immunoreactivity were evident throughout the entire cartilage matrix (light brown). IHC analysis showed that VAP regulate the expression of β-catenin and collagen II protein level in facet joint. IF showed MMP13 (c), Admts4 (d) and Admts5 (e) protein levels were significantly increased in OA model group compare with control group. In VAP groups, MMP13, Admts4 and Admts5 protein levels were reduced. VAP regulate the gene expression encoding for ECM degradation in facet joint. Lumbar disc tissues were harvest to proceed wstern blot analysis (n = 5), the result indicate that compared with the WT group, protein level of β-catenin rise apparently in model group. Compared with model group, protein level of β-catenin declined in VAP different dosage group. VAP may partially downregulate the expression of β-catenin protein level (f). The mRNA expression of ECM degradation enzymes MMP13, ADAMTS4 and ADAMTS5 was evaluated by real-time polymerase chain reaction (n = 5). Values were expressed as mean ± SD. * P < 0.05,** P < 0.01 vs Control group; ^#P < 0.05,^##P < 0.01 vs OA group (g)