TNF and intervertebral disk degenerative disorder: To this end, the Fas receptor is expressed shortly after the onset of disc degeneration [24], while a high mechanical load, decreased production of important matrix proteins (such as type II collagen and aggrecan), and increased production of degradative, inflammatory, and catabolic molecules (such as TNF, ILs, MMPs, cathepsin, aggrecanase, lysozyme, nitric oxide, and free radicals) are also implicated causally [25].