Fig. 7: Model of PTX3 regulation of synovial macrophage polarization and disrupted chondrocyte homeostasis during OA.

Decreased miR-224-5p promotes M1-polarized OA macrophage and chondrocyte secretion of PTX3. Increased PTX3 promotes increased M1 polarization of synovial macrophages and the secretion of inflammatory cytokines that disrupt chondrocyte homeostasis, accelerating OA progression.