Suppression of inducible nitric oxide synthase expression induced by Toll-like receptor agonists by (E)-1-(2-(2-nitrovinyl)phenyl)pyrrolidine

Toll-like receptors (TLRs) recognize many pathogen-associated molecular patterns and induce innate immunity. TLR signaling pathways induce the activation of various transcription factors, such as nuclear factor-κB (NF-κB), leading to the induction of pro-inflammatory gene products, such as inducible nitric oxide synthase (iNOS). Here, we investigated the effect of an (E)-1-(2-(2-nitrovinyl)phenyl)pyrrolidine (NVPP), previously synthesized in our laboratory, on inflammation by modulating NF-κB activation and iNOS expression induced by TLR agonists in murine macrophages. NVPP suppressed NF-κB activation and iNOS expression induced by lipopolysaccharide (TLR4 agonist), polyriboinosinic polyribocytidylic acid (TLR3 agonist), and macrophage-activating lipopeptide 2 kDa (TLR2 and TLR6 agonist). All the results suggest that NVPP is suitable for development as a new anti-inflammatory drug.