Expression and clinical significance of receptor-interacting protein serine-threonine kinases 1 in the nucleus pulposus of patients with lumbar disc herniation

Abstract

To investigate the expression and clinical significance of receptor interacting protein serine-threonine kinases 1 (RIPK1) in the nucleus pulposus of patients with lumbar disc herniation (LDH). Nucleus pulposus tissue specimens of 40 patients with LDH patients underwent surgical treatment from January 2016 to January 2018 as the case group, and nucleus pulposus tissue specimens of 30 patients with lumbar spine fracture underwent surgical treatment at the same time as the control group. The expression of RIPK1 mRNA and protein of receptor interaction were detected by polymerase chain reaction (PCR) and Western blot, respectively. The expression of RIPK1 protein in the nucleus pulposus were detected by immunohistochemical staining. The concentrations of RIPK1 and tumor necrosis factor-α (TNF-α) in nucleus pulposus were detected by ELISA method. The relationship between the concentrations of RIPK1, TNF-α in nucleus pulposus and the Pearce grade of LDH patients was analyzed by one-way ANOVA. The correlation between RIPK1 and TNF-α was analyzed by Pearson. RIPK1 was weakly positively expressed in nucleus pulposus of control group, and RIPK1 protein was positively or strongly positively expressed in case group. The expression of RIPK1 mRNA in nucleus pulposus of case group was higher than that of control group (P<0.05). The expression of RIPK1 protein in nucleus pulposus of case group was higher than that of control group(P<0.05). The RIPK1 concentration in nucleus pulposus of case group was higher than that of control group (P=0.012). The concentration of TNF-α in nucleus pulposus of case group was significantly higher than that of control group (P=0.009). There were significantdifferences in concentrations of RIPK1 and TNF-α in nucleus pulposus of LDH patients with different Pearce classification (P>0.05). The concentration of RIPK1 and TNF-α in nucleus pulposus increased significantly with the increase of Pearce grade. Pearson correlation analysis showed that there was a significant positive correlation between RIPK1 and TNF-α in nucleus pulposus of LDH patients (r=0.781, P<0.001). The expression levels of RIPK1 mRNA and protein in the intervertebral disc tissues of LDH patients are higher than those of normal intervertebral disc tissues, and increased with the increase of Pearce grade, which may be an important factor involved in LDH inflammatory disease.