Effects of kynurenic acid and choline on lipopolysaccharide-induced cyclooxygenase pathway

Abstract Objectives Inflammation can be endogenously modulated by the cholinergic anti-inflammatory pathway via calcium (Ca 2+ )-permeable alpha-7 nicotinic acetylcholine receptor (α7nAChR) ion channel expressed in immune cells. α7nAChR agonist choline and tryptophan metabolite kynurenic acid (KYNA) produces immunomodulatory effects. This study aimed to determine effects of KYNA on lipopolysaccharide (LPS)-induced cyclooxygenase (COX)-2 pathway. Methods In vitro inflammation model was produced LPS administration macrophage To effective concentrations, were applied with increasing concentrations LPS-induced inflammatory parameters investigated. The involvement nAChR mediated investigated use non-selective selective antagonists. COX-2 enzyme, PGE 2 , TNFα, NF-κB intracellular Ca levels analyzed. Results expression, TNFα decreased treatment while α7nAChRs increased. also showed an effect same parameters. Additionally, increased effectiveness these mediators. Conclusions Our data suggest a possible interaction between kynurenine system modulation response macrophages.