Expression Of MMP-2,MMP-14 And IL-6 Of Patients With Tuberculous Intervertebral Discs And Their Clinical Significance

Objectives:To investigate the role of matrix metalloproteinase-2(MMP-2),matrix metalloproteinase-14(MMP-14)and interleukin-6(IL-6)in the destruction mechanism of intervertebral discs of spinal tuberculosis patients and to provide the theory base for the treatment to spinal tuberculosis by examining the expression of MMP-2,MMP-14 and IL-6 in the tuberculous intervertebral discs.Methods:Tuberculosis group:From May 20,2015 to August 30,2016,we collected 40 cases of intervertebral disc tissue from patients that underwent surgery for spinal tuberculosis in the People's Hospital of Guangxi Zhuang Autonomous Region.Intervertebral disc herniation group:From May 20,2015 to August 30,2016,we collected 40 cases of intervertebral disc tissue from patients that underwent surgery for intervertebral disc herniation in the People's Hospital of Guangxi Zhuang Autonomous Region.Control group:From May 20,2015 to August 30,2016,we collected 40 cases of intervertebral disc tissue from patients that underwent surgery for acute burst fracture of vertebral in the People's Hospital of Guangxi Zhuang Autonomous Region.The intervertebral disc samples were stored immediately in liquid nitrogen when obtained until we extracted RNA and proteins in the tissue samples.The expression of MMP-2 and MMP-14 mRNA in the intervertebral discs of different groups were examined by real-time PCR(RT-PCR).The expression of MMP-14 protein in the intervertebral discs of different groups was examined by western blot.Expression of IL-6 was examined by immunohistochemical technique.We combined the method of laboratory examination and clinical questionnaire to investigate the correlation of MMP-2 and MMP-14 mRNA with the clinicopathological profile of patients suffering from tuberculous intervertebral discs.Results:The result of RT-PCR showed that the expression of MMP-2 and MMP-14 in tuberculosis group and intervertebral disc herniation group were significantly increased when compared with the normal group(P<0.05).The expression of MMP-2 in tuberculosis group was significantly higher than that in intervertebral disc herniation group(P<0.05).The expression of MMP-14 in tuberculosis group was higher than that in intervertebral disc herniation group,but the difference was not statistically significant(P>0.05).The result of western blot showed that the expression of MMP-14 protein in tuberculosis group and intervertebral disc herniation group was significantly higher than that in normal group(P<0.05).The expression of MMP-14 protein in tuberculosis group was higher than that in disc herniation group,but the difference was not statistically significant P>0.05).The result of immunohistochemical technique showed that the expression of IL-6 in tuberculosis group and intervertebral disc herniation group was significantly higher than that in normal group(P<0.05).The expression of IL-6 in tuberculosis group was higher than that in disc herniation group,the difference was statistically significant(P<0.05).The analysis of clinicopathological profile of patients showed that the expression level of MMP-2 in tuberculosis group was positively correlated with age(P = 0.007)and smoking habits(P = 0.004),and there were no correlation between its expression and the sex,employment,pain intensity,level of intervertebral disc herniation,symptom duration,C-reactive protein(CRP),erythrocyte sedimentation rate(ESR)(P>0.05).There was no correlation between the expression level of MMP-14 and the sex,age,employment,smoking habits,pain intensity,level of intervertebral disc herniation,symptom duration,CRP and ESR(P>0.05).Conclusion:The expressions of MMP-2,MMP-14 and IL-6 in tuberculous and degenerative intervertebral disc tissue were significantly increased,suggesting that they were correlated to destruction of tuberculous intervertebral disc and disc herniation.This study also found that the expression of MMP-2 in tuberculous intervertebral disc was positively correlated with the smoking,suggesting that smoking may aggravate the destruction of tuberculous intervertebral disc.