The Role of Interleukin 4 and Il-4Ra in Intervertebral Disc Degeneration: Investigation of Single Nucleotide Polymorphisms in Genes and a Systematic Review & Meta-Analysis of Il-4 Expression Level Publisher Pubmed



Hanaei S^{1, 2, 3} ; Abdollahzade S⁴ ; Sadr M¹ ; Mirbolouk MH⁵ ; Fattahi E⁵ ; Khoshnevisan A⁵ ; Rezaei N^{2, 3, 6} Show Affiliations
Source: British Journal of Neurosurgery Published:2020

Abstract

Background: Intervertebral disc degeneration (IVDD) is a multifactorial disease that is sensitive to the balance between anti-inflammatory and pro-inflammatory cytokines. This study investigated the single nucleotide polymorphisms (SNPs) of interleukin 4 (IL-4) in IVDD. Methods: Genomic DNA of peripheral mononuclear cells of 76 IVDD patients and 140 healthy controls were investigated for three SNPs of IL-4 (rs2243248 (−1098G/T), rs2243250 (−590 C/T), rs2070874 (−33 C/T)) and 1 SNP of IL-4RA (rs180275, +1902 A/G) through PCR-SSP method. Results: The ‘C’ allele frequency of IL-4 rs2243250 was 104 in 76 patients, while it was 149 in 140 controls (OR = 2, p =.001); also this SNP was significantly associated with post-operative pain reduction. The ‘C’ allele of IL-4 rs2070874 (130 in 76 patients, and 200 in 140 controls, OR = 2.66), and the ‘CC’ genotype were more frequent among patients (OR = 3.98, p <.001) than controls. ‘TTT’ haplotype was more common in controls (OR = 0.36, p <.001) and ‘TCC’ was also more common in patients (OR = 1.75, p =.012). A meta-analysis of previous studies found significantly higher IL-4 levels in disc tissues of IVDD patients, which was not similarly found in blood samples. Conclusion: The immune system plays an important role in IVDD. The extent and progress of the disease vary significantly with IL-4 level. Meanwhile, the rs2070874 and rs2243250 SNPs of IL-4 were significantly associated with IVDD in Iranian patients. © 2019, © 2019 The Neurosurgical Foundation.