title: Folic acid inhibits lipopolysaccharide-induced inflammatory response in RAW264.7 macrophages by suppressing MAPKs and NF-κB activation.
abstract: OBJECTIVE
  The aim of the present study was to investigate the effects of folic acid on the inflammatory responses to lipopolysaccharide (LPS) in RAW264.7 cells and the signal transduction pathways involved.
  
  
  METHODS
  RAW264.7 macrophages were used. The production of nitric oxide (NO) was determined by the Griess test. The protein levels and mRNA expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) were determined by ELISA and RT-PCR, respectively. The phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear nuclear factor-kappa B (NF-κB) p65 protein were analyzed by Western blotting.
  
  
  RESULTS
  Folic acid inhibited LPS-induced production of NO, TNF-α and IL-1β with decreased mRNAs of inducible nitric oxide synthase (iNOS), TNF-α and IL-1β. Further study showed that folic acid inhibited the LPS-induced phosphorylation of MAPKs and the nuclear translocation of NF-κB.
  
  
  CONCLUSIONS
  Folic acid inhibits the inflammatory response of RAW 264.7 cells to LPS through inhibiting the MAPKs and NF-κB pathways.
authors.affiliation: Department of Preventive Medicine, School of Public Health, Sun Yat-sen University, 74 Zhongshan Road 2, Guangzhou, 510080, People's Republic of China.
authors.forename: Dan
authors.initials: D
authors.lastname: Feng
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Xia
authors.forename: Jing
authors.initials: J
authors.lastname: Ma
mesh_terms: D000818:Animals; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects*; D005492:Folic Acid / Q000494:pharmacology*; D006801:Humans; D053583:Interleukin-1beta / Q000235:genetics / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000276:immunology; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000276:immunology; D009569:Nitric Oxide / Q000276:immunology; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000276:immunology; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology; D014803:Vitamin B Complex / Q000494:pharmacology
chemical_list: D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D014803:Vitamin B Complex; D009569:Nitric Oxide; D005492:Folic Acid; D052247:Nitric Oxide Synthase Type II; D020928:Mitogen-Activated Protein Kinases