Influence of IL-20 on lumbar disc degeneration:An experimental study

OBJECTIVE To determine the influence of IL-20 on the development of lumbar degeneration. METHODS The study design was prospective and carried out in Tianjin Fourth center Hospital, Tianjin, China between Jan 2012 and Jan 2014. Sixty-nine patients with degenerative disc disease treated surgically were included in experimental group, and fifteen patients with normal discs were included in control group. The evaluation of disc degeneration was performed using T2-weighted sagittal MRI according to the Modified Pfirrmann Grading System. After surgery, the intervertebral disc in both groups was collected and the content of proteoglycan and IL-20 were measured, the correlation between the content of IL-20, proteoglycan and the degeneration grade of lumbar disc was analyzed. RESULTS Compared to control group, the content of proteoglycan in experimental group is significantly lower (P=0.000), but IL-20 is significantly higher (P=0.001). In addition, with the advance of intervertebral disc degeneration, the content of IL-20 increase, while proteoglycan decrease gradually. There is significant correlation between the content of proteoglycan (p=0.001), IL-20 (p=0.002) and the degeneration grade of lumbar disc. CONCLUSION In patients with degenerative disc disease, the content of IL-20 and proteoglycan has significant correlation with degeneration grade of lumbar disc, and IL-20 may promote the degeneration of lumbar disc by affecting the synthesis of proteoglycan.