Abstract: Objective To determine the role of c-Jun N-terminal kinase (JNK) signaling in annulus fibrosus cells response to interleukin (IL)-1. Methods Rat annulus fibrosus cells cultured in monolayer were exposed to IL-1, with or without JNK inhibition by SP600125. RNA was isolated for Real-Time polymerase chain reaction (PCR) after 24 h stimulation. Results IL-1 upregulation of mRNA for inducible nitric oxide synthase (iNOS), IL-6, cyclooxygenase (Cox)-2, matrix metalloproteinase (MMP)-3, MMP-13 were blunted by JNK inhibition, while downregulation of collagenⅠand insulin-like growth factor (IGF)-1 were also reversed by JNK inhibition. Conclusion JNK signaling inhibition can be a therapeutic target for blocking intervertebral disc degeneration induced by IL-1.

Key words: annulus fibrosus cells, signal transduction, c-Jun N-terminal kinase, interleukin-1, rats