Figures & data
Figure 1. Dysregulated secreted proteins in OA SF and IL-1β-induced chondrocyte S100A12 upregulation. (A) Semi-quantitative antibody arrays were used to outline the proteome of SF. (B) Scatter plot of protein expression levels. (C-D) GO and KEGG analysis on DEPs. (E, G) the expression of S100A12 in mRNA levels increased in chondrocytes under IL-1β stimulation. (F, H) the expression of S100A12 in protein levels increased in chondrocytes under IL-1β stimulation. (I, J) the extracellular S100A12 of chondrocyte supernatant was detected by ELISA under IL-1β stimulation. Data represent the mean ± standard deviation (3 independently repeated experiments); *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant (Student t test). BFA, Brefeldin A.
Table 1. The 20 most upregulated proteins in OA SF compared with non-OA SF.
Table 2. The 20 most downregulated proteins in OA SF compared with non-OA SF.
Figure 2. S100A12 is involved in the pathology of OA synovitis. (A) S100A12 levels in different tissues of OA or non-OA joints. (B) HE and S100A12 IHC staining of OA and non-OA synovium (C, D) statistical analysis of synovitis scores and S100A12 IHC in OA and non-OA synovium. Data represent the mean ± standard deviation (3 independently repeated experiments); *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant (Student t test). (E) Correlation analysis between synovitis score and S100A12 concentration (Pearson).
Figure 3. S100A12 promotes M1 macrophage polarization. (A) THP-1 cells were induced into M0 macrophages. (B) Western blot analysis of protein levels in THP-1-derived macrophages treated with different concentrations of exogenous S100A12. (C-J) qPCR analysis of mRNA levels in THP-1-derived macrophages treated with exogenous S100A12 (2ug/ml). Data represent the mean ± standard deviation (3 independently repeated experiments); *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant (Student t test).
Figure 4. S100A12 promotes macrophage M1 polarization via the NF-κB signaling pathway. (A) STRING prediction for S100A12. (B) Western blot analysis of protein levels in THP-1-derived macrophages treated with exogenous S100A12 (2ug/ml). (C, D) Representative immunofluorescence images of THP-1-derived macrophages treated with indicated conditions and quantitative analysis of p65 nuclear translocation. Data represent the mean ± standard deviation (3 independently repeated experiments); *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant (Student t test). (E-G) Western blot and quantification analysis of protein levels in THP-1-derived macrophages with or without BAY 11–7082 pretreated. BFA, Brefeldin A. Data represent the mean ± standard deviation (3 independently repeated experiments); *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant (ANOVA).
Figure 5. Construction of the ceRNA network regulating S100A12. (A) The potential miRnas targeting S100A12 were predicted using miRDB, miRmap, miRwalk, and TargetScan databases. Several common miRnas were obtained through screening with a venn diagram. The horizontal bar represents the number of elements shared in one or more lists. For example, 115 elements exclusively exist in a single list, while 30 elements coexist in 2 lists. (B) LncACTdb was used to predict lncRnas that may bind to these miRnas, and the network was visualized. (C) Venn diagram of predicted lncRnas and lncRnas detectable by GPL20844. (D) Volcano plot for differential analysis. (E) Venn diagram of differentially expressed lncRnas and lncRnas positively correlated with S100A12. (F,G) correlation analysis between LINC00894 expression and S100A12 expression (Pearson).
Figure 6. The schematic diagram summarizes the content of this study and the role of S100A12 in OA.
