The role of cytokines in degenerative spine disorders

Background: Degenerative spine disorders (DSD) are the most frequent reason of morbidity in adults. Commonly DSD includes degenerative disorders of intervertebral discs (IVDs), spinal stenosis and degenerative spondylolisthesis (SL). There is increasing evidence about significant role of cytokines in DSD pathogenesis, symptomathology and progression, but their protective levels remain still unknown.

Material and Methods: The aim of presented study was to provide quantitative and qualitative analysis of cytokine, chemokine and growth factors levels in individual parts of IVDs - annulus fibrosus (AF) and nucleus pulposus (NP) - separately and in facet joints (FJ) subchondral bone of patients with DSD and in controls - healthy subjects during a multiorgan procurement procedure. Bio-Plex^® assay was used to measure concentrations of 27 different cytokines in tissue of patients with DSD. Their concentrations in tissues of healthy subjects during a multiorgan procurement procedure represented protective levels.

Results: The Bio-Plex^® assay revealed significant differences between the patients suffered from degenerated and herniated IVDs and from lumbar SL and controls in cytokines, chemokines and growth factor profiles suggested that pro-inflammatory changes of both NP and AF were dominated in herniated IVDs, whereas the same tissue of lumbar SL patients exhibited much more complex changes in cytokine levels suggested o only ongoing inflammation (IL-6, IL-8, MCP-1, TNF-α), abut also antiinflammatory processes (IL-ra, IL-10) or connective tissue remodeling (PDGF-bb, IL-17, VEGF). The different mediators were found elevated in lumbar SL samples of subchondral FJ bone. These also confirmed ongoing inflammation, accelerated bone resorption and formation and increased fibroblasts activity in FJ bone.

Conclusion: The study supported the significant involvement of several cytokines, chemokines and growth factors in the pathogenesis of DSD. These cytokines should represent future potential targets for new biological treatment able to slow DSD progression as well as factor determining prognosis of DSD.