Broussonin E suppresses LPS-induced inflammatory response in macrophages via inhibiting MAPK pathway and enhancing JAK2-STAT3 pathway

Chin J Nat Med. 2019 May 20;17(5):372-380. doi: 10.1016/S1875-5364(19)30043-3.

Abstract

Macrophages play an important role in inflammation, and excessive and chronic activation of macrophages leads to systemic inflammatory diseases, such as atherosclerosis and rheumatoid arthritis. In this paper, we explored the anti-inflammatory effect of broussonin E, a novel phenolic compound isolated from the barks ofBroussonetia kanzinoki, and its underlying molecular mechanisms. We discovered that Broussonin E could suppress the LPS-induced pro-inflammatory production in RAW264.7 cells, involving TNF-α, IL-1β, IL-6, COX-2 and iNOS. And broussonin E enhanced the expressions of anti-inflammatory mediators such as IL-10, CD206 and arginase-1 (Arg-1) in LPS-stimulated RAW264.7 cells. Further, we demonstrated that broussonin E inhibited the LPS-stimulated phosphorylation of ERK and p38 MAPK. Moreover, we found that broussonin E could activate janus kinase (JAK) 2, signal transducer and activator of transcription (STAT) 3. Downregulated pro-inflammatory cytokines and upregulated anti-inflammatory factors by broussonin E were abolished by using the inhibitor of JAK2-STAT3 pathway, WP1066. Taken together, our results showed that broussonin E could suppress inflammation by modulating macrophages activation statevia inhibiting the ERK and p38 MAPK and enhancing JAK2-STAT3 signaling pathway, and can be further developed as a promising drug for the treatment of inflammation-related diseases such as atherosclerosis.

Keywords: Broussonin E; Inflammation; Janus kinase 2; Macrophage polarization; Signal transducer and activator of transcription 3.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / chemistry
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Differentiation / drug effects
  • Cell Differentiation / immunology
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Inflammation Mediators / metabolism
  • Janus Kinase 2 / antagonists & inhibitors
  • Janus Kinase 2 / metabolism
  • Lipopolysaccharides / pharmacology
  • Macrophages / drug effects*
  • Macrophages / immunology*
  • Macrophages / metabolism
  • Mice
  • Molecular Structure
  • Phenols / chemistry
  • Phenols / pharmacology*
  • Phosphorylation / drug effects
  • RAW 264.7 Cells
  • STAT3 Transcription Factor / antagonists & inhibitors
  • STAT3 Transcription Factor / metabolism
  • Signal Transduction / drug effects*
  • Tumor Necrosis Factor-alpha / metabolism
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Anti-Inflammatory Agents
  • Inflammation Mediators
  • Lipopolysaccharides
  • Phenols
  • STAT3 Transcription Factor
  • Stat3 protein, mouse
  • Tnf protein, mouse
  • Tumor Necrosis Factor-alpha
  • Jak2 protein, mouse
  • Janus Kinase 2
  • Extracellular Signal-Regulated MAP Kinases
  • p38 Mitogen-Activated Protein Kinases