title: Forsythin inhibits lipopolysaccharide-induced inflammation by suppressing JAK-STAT and p38 MAPK signalings and ROS production.
abstract: OBJECTIVE
  Forsythin (FOR) is an active ingredient extracted from the fruit of the medicinal plant Forsythia suspensa (Thunb.) Vahl. Here, we investigated the effect of FOR on LPS-induced inflammatory response and the underlying molecular mechanisms in RAW264.7 macrophages.
  
  
  METHODS
  RAW264.7 cells were pre-treated with or without FOR and then stimulated with or without LPS. The productions of TNF-α, IL-1β, IL-6, PGE2 and NO were determined by ELISA and nitrite analysis, respectively. The expressions of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were measured by Western blotting and RT-PCR analysis. The activations of signaling molecules were detected by Western blotting using phosphorylation specific antibodies. Reactive oxygen species (ROS) production was determined by ROS assay.
  
  
  RESULTS
  LPS-induced productions of IL-1β, IL-6, TNF-α, NO and PGE2 were inhibited by FOR in a dose-dependent manner. FOR also suppressed the LPS-elevated expressions of iNOS and COX-2. Further investigations revealed that FOR significantly inhibited the LPS-induced activations of JAK-STATs and p38 MAPKs, but not of IKKα/β in LPS-stimulated RAW264.7 cells. Additionally, FOR interfered with both JAK-STATs and p38 MAPKs signaling pathways to modulate the expressions of IL-1β, IL-6, TNF-α, iNOS and COX-2. Furthermore, FOR reduced the LPS-induced ROS accumulation, validating that FOR serves as an antioxidant.
  
  
  CONCLUSIONS
  Our data suggested that FOR exerts anti-inflammatory action, at least in part, via suppressing LPS-induced activation of JAK-STATs and p38 MAPKs signalings and production of ROS in macrophage cells.
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing, 210046, Jiangsu, People's Republic of China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Pan
authors.forename: Xiang
authors.initials: X
authors.lastname: Cao
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.forename: Yimiao
authors.initials: Y
authors.lastname: Xu
authors.forename: Qiuyue
authors.initials: Q
authors.lastname: Wu
authors.forename: Jing
authors.initials: J
authors.lastname: Bai
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Yin
authors.forename: Lan
authors.initials: L
authors.lastname: Luo
authors.forename: Lei
authors.initials: L
authors.lastname: Lan
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology*; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D005663:Furans / Q000494:pharmacology*; D053612:Janus Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008070:Lipopolysaccharides; D051379:Mice; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D050791:STAT Transcription Factors / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D019086:Bridged Bicyclo Compounds, Heterocyclic; D016207:Cytokines; D005663:Furans; D008070:Lipopolysaccharides; D017382:Reactive Oxygen Species; D050791:STAT Transcription Factors; C423337:forsythenin; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D053612:Janus Kinases; D048051:p38 Mitogen-Activated Protein Kinases