title: [Astragaloside IV regulates STAT1/IκB/NF-κB signaling pathway to inhibit activation of BV-2 cells].
abstract: OBJECTIVE
  The study was aimed to investigate the inhibitory effect and mechanism of astragaloside IV (ASI) on the activation of microglial cells.
  
  
  METHODS
  After pre-incubated with ASI for 2 h, microglial cells BV-2 were stimulated with interferon-γ (IFN-γ) for 1. 5 h and 24 h, respectively. Secretion of nitric oxide (NO) in the medium was measured by Griess method. Production of tumor necrosis factor alpha (TNF-α) was detected by ELISA approach. Cellular gene expressions of CD11b, TNF-α, interleukin 1β (IL-1β) and induced nitric oxide synthase (iNOS) were examined by quantitative-PCR analysis. Total and phosphorylation of STAT1, IκB and NF-κB was analyzed by Western blot method.
  
  
  RESULTS
  ASI could significantly inhibit the increased secretion of TNF-α and NO from BV-2 cells upon IFN-γ stimulation (P < 0.001). Further study showed that ASI significantly down-regulated gene expression of IL-1β and TNF-α (P < 0.01, P < 0.05) and exhibited a trend to reduce that of iNOS. IFN-γ and ASI have no obvious effect on gene expression of CD11b. Moreover, ASI inhibited the phosphorylation of STAT1, IκB and NF-κB elicited by IFN-γ stimulation.
  
  
  CONCLUSIONS
  ASI could restrain microglial activation through interfering STAT1/IκB/NF-κB signaling pathway, reducing gene expres- sion of IL-1β and TNF-α, and thus inhibiting the production of proinflammatory mediators such as NO and TNF-α.
authors.forename: Yi-xin
authors.initials: YX
authors.lastname: He
authors.forename: Hai-lian
authors.initials: HL
authors.lastname: Shi
authors.forename: Hong-shuai
authors.initials: HS
authors.lastname: Liu
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.forename: Bei-bei
authors.initials: BB
authors.lastname: Zhang
authors.forename: Xiao-jun
authors.initials: XJ
authors.lastname: Wu
authors.forename: Zheng-tao
authors.initials: ZT
authors.lastname: Wang
mesh_terms: D000818:Animals; D027883:Astragalus Plant / Q000737:chemistry*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D020672:I-kappa B Proteins / Q000235:genetics / Q000378:metabolism*; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D050794:STAT1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D012503:Saponins / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects*; D014315:Triterpenes / Q000494:pharmacology*
chemical_list: D004365:Drugs, Chinese Herbal; D020672:I-kappa B Proteins; D016328:NF-kappa B; D050794:STAT1 Transcription Factor; D012503:Saponins; C494080:Stat1 protein, mouse; D014315:Triterpenes; D009569:Nitric Oxide; C052064:astragaloside A; D007371:Interferon-gamma; D052247:Nitric Oxide Synthase Type II