Fig. 2.

The role of proinflammatory factors in the pathogenesis of knee osteoarthritis schematic diagram. IL‐1β, TNF‐α, IL‐6, and other pro‐inflammatory factors bind to their corresponding receptors, activate NF‐kB and MAPK signaling pathways. By promoting the expression of ADAMT‐4, ADAMT‐5, MMP1, MMP3, MMP13, and other enzymes, it inhibits the synthesis of proteoglycans and collagen resulting in ECM degradation. In addition, the same signaling pathway can increase the expression of inflammatory mediators such as COX‐2, PGE‐2, NO, iNOS, and induce inflammatory factors such as IL‐6 and TNF‐α to aggravate the inflammatory response.