Formation Of Nucleus Pulposus-Induced Disc Hernia-Like Nodules On The Disc Surface Is Not Induced By TNF

It was recently seen that puncture of an intervertebral disc in the rat induced disc hernia-like nodules over the puncture site and that the presence of nucleus pulposus was necessary to produce such nodules. Since TNF from the nucleus pulposus have been found to be involved in pain production the aim was to see if also TNF was involved in the formation of such nodules. Two TNF-inhibitors, infliximab and methotrexate, were administered to rats following disc puncture. Non-treated animals were used as controls. Macroscopic evaluation after one and two weeks did not demonstrate any notable differences between non-treated and treated animals. The data thus indicate that TNF is not involved in the formation of nucleus pulposus-induced disc hernialike nodules on the disc surface. This may instead be induced by other bioactive substances derived from the nucleus pulposus, such as growth factors. However, further studies with direct administration of TNF-inhibitors must also be performed to understand the contribution of TNF in this regard. CONFLICT OF INTEREST The author is CEO and part owner of the company Sciaticon AB that holds patent on pharmacological treatment of low back pain and sciatica by TNF-inhibition.