TLR4/NF-κB signaling pathway gene single nucleotide polymorphisms alter gene expression levels and affect ARDS occurrence and prognosis outcomes

BACKGROUND: To study the occurrence and prognosis of acute respiratory distress syndrome (ARDS) using single nucleotide polymorphisms (SNPs) of TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 loci in the TLR4/NF-κB pathway. METHODS: Genotypes were analyzed for TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 loci. Plasma TNF-α and IL-6 levels and MyD88 mRNA expression in peripheral blood mononuclear cells (PBMCs) of 300 ARDS patients and 300 non-ARDS patients (control group) were examined. The patients were followed up for 60 days, and the prognosis outcome was recorded. RESULTS: The TNF-α rs1800629 locus A allele and the IL-6 rs1800796 locus G allele were found to be risk factors for ARDS (adjusted OR = 1.452, 95% CI: 1.211–1.689, P < .001 and adjusted OR = 1.205, 95% CI: 1.058–1.358, P = .005, respectively). The G allele at MyD88 rs7744 locus was a protective factor against ARDS (adjusted OR = 0.748, 95% CI: 0.631–0.876, P < .001). Compared with the other groups, homozygotes for TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 loci had higher expression levels, of which homozygotes for TNF-α rs1800629 and IL-6 rs1800796 loci had lower 60-day survival rates, while MyD88 rs7744 locus homozygotes had a higher 60-day survival rate. CONCLUSION: The effect of TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 SNPs on gene expression level is a likely cause of ARDS occurrence and poor prognosis.