Vitamin B6 suppresses NF-kappaB activation in LPS-stimulated mouse macrophages

Int J Mol Med. 2005 Dec;16(6):1071-5.


Although vitamin B6 has been supposed to have anti-inflammatory effects, the molecular mechanism is not fully understood. To explore the mechanism of anti-inflammatory effects of vitamin B6, we have examined the effect of vitamin B6 on lipopolysaccharide (LPS)-stimulated inflammatory response in RAW 264.7 macrophages. This study demonstrated that vitamin B6 (pyridoxal) pretreatment of RAW cells inhibited LPS-induced expression of iNOS and COX-2 at the mRNA and protein levels. Vitamin B6 inhibited LPS-induced nuclear translocation of the NF-kappaB, the proinflammatory transcription factor, with reduction of the extent of LPS-induced IkappaBalpha degradation in RAW cells. Although vitamin B6 did not affect cellular proteasome activity, in vitro phosphorylation analysis with glutathione S-transferase-fused IkappaBalpha has shown that vitamin B6 suppressed LPS-induced IkappaB kinase activation. Furthermore, we demonstrated that elevating dietary vitamin B6 suppressed NO production in vivo in response to LPS administration. These observations suggest that the anti-inflammatory effect of vitamin B6 is mediated by suppression of NF-kappaB activation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Cyclooxygenase 2 / metabolism
  • Gene Expression Regulation / drug effects
  • I-kappa B Kinase / metabolism
  • I-kappa B Proteins / metabolism
  • Lipopolysaccharides / pharmacology*
  • Macrophages / drug effects*
  • Macrophages / metabolism*
  • Male
  • Mice
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / antagonists & inhibitors*
  • NF-kappa B / metabolism
  • Nitric Oxide / biosynthesis
  • Nitric Oxide Synthase Type II / metabolism
  • Proteasome Endopeptidase Complex / metabolism
  • Protein Processing, Post-Translational / drug effects
  • Pyridoxal / pharmacology
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Wistar
  • Vitamin B 6 / pharmacology*


  • I-kappa B Proteins
  • Lipopolysaccharides
  • NF-kappa B
  • Nfkbia protein, mouse
  • Nfkbia protein, rat
  • RNA, Messenger
  • NF-KappaB Inhibitor alpha
  • Nitric Oxide
  • Pyridoxal
  • Vitamin B 6
  • Nitric Oxide Synthase Type II
  • Cyclooxygenase 2
  • I-kappa B Kinase
  • Proteasome Endopeptidase Complex