Fig. 4. Molecular regulatory function of AnxA1 in inflammation and pathological bone resorption.

a Effects of AnxA1 of the expression of transcriptional factors involved in inflammation and osteoclast differentiation. b Inhibitory effects of AnxA1 on osteoclast formation in macrophages stimulated with UHMWPE debris. Results represent the mean ± SEM of 6 samples. Right panel shows representative images for stained osteoclasts by TRAP. Scale bars are 100 µm. c, d Inhibitory effects of AnxA1 on osteoclast differentiation and bone resorption. Macrophages were stimulated with RANKL in the presence of different concentrations of AnxA1. d Quantification of bone resorption area (pitting) formed by RANKL-stimulated macrophages in a 100 ng/mL concentration of AnxA1 in bone resorption assay. Results represent the mean ± SEM of 3 samples. Significant difference between the two groups was determined by two-tailed Student’s t test and for multiple groups by one-way ANOVA, followed by Tukey’s multiple-comparison procedure. Scale bars are 200 µm. e Heat map based on a KEGG pathway enrichment analysis for upregulated genes in macrophages stimulated with RANKL and AnxA1. f MA plot analysis for transcript expression levels of significantly up-or down-regulated genes in macrophages stimulated with RANKL and AnxA1 (p  <  0.05) (n  =  3). g Detection of PPAR-γ by Western blot analysis in macrophages stimulated with AnxA1 at different time points. Left panel shows the quantification of the relative intensity of the detected bands and results represent the mean ± SEM of 3 samples. Significant difference among the groups was determined by one-way ANOVA, followed by Tukey’s multiple-comparison procedure. **p < 0.001, ***p < 0.0001, ****p < 0.00001. ns indicates no significant difference. Source data are provided as a Source Data file.