Here we examined circulating concentrations of inflammatory cytokines (IFN-γ, TNF-α, IL-1β, IL-6), and the acute phase protein CRP alongside plasma tryptophan, kynurenine, kynurenic acid (KYNA) and 3-hydroxyanthranilic acid (3-HAA) concentrations, and whole blood mRNA expression of IDO, kynurenine aminotransferases (KAT I and II), kynurenine-3-monooxygenase (KMO), kynureninase and SERT in patients with major depressive disorder (MDD) compared with age and sex-matched controls.
The present study suggests a negative effect of the IL1B gene on pharmacological response and amygdala and ACC function involving the same genotypes of two SNPs (rs16944, rs116343), which taken together increase the risk of nonremission over 6 weeks of antidepressant treatment in MDD.