MMP13 and intervertebral disk degenerative disorder: The p38 MAPK can affect the expression of MMP1, MMP3, MMP13, IL-6, IL-8, COX-2, iNOS, and TGF-β, as well as control the expression of anabolic and anti-catabolic genes such as proteoglycans, collagen I protein and collagen II, leading to disc degeneration (Zhao et al., 2021).