Mitogen-activated protein kinase p38 is a serin/threonine kinase originally isolated from lipopolysaccharide stimulated monocytes. There are 4 isoforms; p38-a activation has been most widely studied for inflammation...
Inflammatory cytokines may act during the initial stages of disc degeneration. Role of Tumor Necrosis Factor-alpha, Interleukin-8, and Dexamethasone in the Focal Adhesion Kinase Expression by Human Nucleus Pulposus Cell. Bo Keun Jee, et al.
The same cytokine may have different effects in different circumstances. (This is called ' pleotropy '). See below chart for key functions of significant cytokines.