Effects of ozone on expression of NO and IL-6 in nucleus pulposus of patients with lumbar intervertebral disc herniation in vitro

Objective To evaluate the effects of ozone (O3) on the expression of nitric oxide (NO) and interleukin-6 (IL-6) in the nucleus pulposus of patients with lumbar intervertebral disc herniation in vitro. Methods Nucleus pulposus specimens were obtained from 16 patients with lumbar intervertebral disc herniation under intervertebral foramen endoscope. Each specimen was randomly divided into 3 groups (n= 16 each) using a random number table: control group (group C), O320 μg/ml group (O320 group) and O340 μg/ml group (O340 group). O320 and 40 μg/ml 2 ml were injected into the nucleus pulposus in O320 and O340 groups, respectively. The nucleus pulposus was cultured for 72 h in vitro 20 min later. The culture medium was collected for detection of NO and IL-6 concentrations. The nucleus pulposus tissues were obtained for determination of the expression of inducible nitric oxide synthase (iNOS) and IL-6 mRNA using real-time fluorescent quantitative PCR. Results Compared with group C, the concentrations of NO and IL-6 in the culture medium were significantly decreased, and the expression of iNOS and IL-6 mRNA in nucleus pulposus tissues was down-regulated in O320 and O340 groups. There were no significant differences in the parameters mentioned above between O320 group and O340 group. Conclusion The mechanism by which O3 treats pain in waist and legs is related to reduced production of NO in the intervetebral disc and decreased local inflammatory responses in the patients with lumbar intervertebral disc herniation. Key words: Ozone; Nitric oxide; Interleukin-6; Intervertebral disk displacement