Muscone Protects Vertebral End-plate Degeneration by Antiinflammatory Property

Most chronic neck pain is the result of degeneration of the cervical spine. IL-1β may play an important role in intervertebral disc degeneration. This being the case, inhibiting IL-1β could provide a therapeutic approach for reducing or preventing disc degeneration. Muscone reportedly relieves pain and suppresses inflammation. Therefore, we asked whether muscone, a potent antiinflammatory agent, could reduce proinflammatory cytokines in vitro (end-plate cartilage cultures) and end-plate degeneration in vivo (a rat model that induces intervertebral disc degeneration). In vitro, muscone reversed IL-1β-induced upregulation of IL-1β, tumor necrosis factor α, cyclooxygenase 2, inducible nitric oxide synthase, matrix metalloproteinase 13, aggrecanase 2, and nitric oxide and downregulation of Col2α1 and aggrecan. Pretreatment with muscone (6.25, 12.5, 25 μmol/L) inhibited the IL-1β-induced phosphorylation of extracellular signal-regulated kinases 1/2 and c-Jun N-terminal kinase in a dose-dependent manner. In vivo, muscone inhibited the expression of prostaglandin E2, 6-keto-prostaglandin F1α, IL-1β, and tumor necrosis factor α and recovered the structural distortion of the degenerative disc. Our findings suggest muscone is a promising agent for treating intervertebral disc degeneration through its antiinflammatory effects.