Inhibitory effect of litchi (Litchi chinensis Sonn.) flower on lipopolysaccharide-induced expression of proinflammatory mediators in RAW264.7 cells through NF-κB, ERK, and JAK2/STAT3 inactivation

J Agric Food Chem. 2014 Apr 16;62(15):3458-65. doi: 10.1021/jf5003705. Epub 2014 Apr 4.

Abstract

Litchi (Litchi chinensis Sonn.) flower ethanolic extract (LFEE) was found to contain five flavanoids [total amount, 102.73 ± 5.50 mg/g of dried extract (gDE)], nine phenolic acids (total amount, 60.31 ± 4.52 mg/gDE), and proanthocyanidin A2 (79.31 ± 2.95 mg/gDE). LFEE was used to evaluate the inhibitory effects on lipopolysaccharide- (LPS-) induced pro-inflammatory mediators in RAW264.7 cells. The results showed that LFEE treatment could suppress the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the productions of nitric oxide (NO) and prostaglandin E2 (PGE2), and the secretions of pro-inflammatory cytokines [interleukin-1β (IL-1β), IL-6, and tumor necrosis factor α (TNF-α)] in the LPS-mediated RAW264.7 cells. The attenuation of LPS-induced inflammatory responses by LFEE was found to be closely related to the inhibition of the translocation of nuclear factor κB (NF-κB) p50/p65 subunits correlated with suppression of the activation of the inhibitor of κB kinase (IKK) α/β and downregulation of activation of extracellular signal-regulated kinase (ERK) and Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Line
  • Down-Regulation / drug effects
  • Extracellular Signal-Regulated MAP Kinases / genetics
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • Flowers / chemistry
  • Fruit / chemistry
  • Inflammation / drug therapy
  • Inflammation / genetics
  • Inflammation / immunology
  • Inflammation / metabolism*
  • Inflammation Mediators / immunology
  • Janus Kinase 2 / genetics
  • Janus Kinase 2 / metabolism*
  • Lipopolysaccharides / adverse effects
  • Litchi / chemistry*
  • Macrophages / drug effects
  • Macrophages / immunology
  • Mice
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Plant Extracts / pharmacology*
  • STAT3 Transcription Factor / genetics
  • STAT3 Transcription Factor / metabolism*

Substances

  • Anti-Inflammatory Agents
  • Inflammation Mediators
  • Lipopolysaccharides
  • NF-kappa B
  • Plant Extracts
  • STAT3 Transcription Factor
  • Jak2 protein, mouse
  • Janus Kinase 2
  • Extracellular Signal-Regulated MAP Kinases