Attenuation of Innate Immunity by Andrographolide Derivatives Through NF-κB Signaling Pathway

Sci Rep. 2017 Jul 5;7(1):4738. doi: 10.1038/s41598-017-04673-x.

Abstract

Andrographolide derivatives or analogs exhibit potent anti-inflammatory effects in several disease models through NF-κB activity. In this study, we synthesized different andrographolide derivatives and investigated their effects on the toll-like receptor (TLR)-induced production of pro-inflammatory cytokines. Among these compounds, 3b, 5a, and 5b inhibited both TNF-α/NF-κB and TLR4/NF-κB signaling pathways. Treatment with compounds 3b, 5a, and 5b and their structural analogs, 3a and 6b, suppressed the expression of pro-inflammatory cytokines upon the activation of TLR3 and TLR4 ligands. Compounds 3b and 5a, but not 3a, 5b, or 6b, inhibited the nuclear translocation of the NF-κB p65 subunit. Treatment with compounds 3b, 5a, 3a, 5b, and 6b attenuated the phosphorylation of p65 and IκBα. Compounds 6b suppressed the expression of the NF-κB p65 subunit. However, these compounds, except for 5b, did not affect the TLR9-induced NF-κB-independent production of the pro-inflammatory cytokines, TNF-α, and IFN-β. Compound 3b potentially protected mice from LPS-induced acute pulmonary inflammation through the inhibition of p65 phosphorylation and the decrease of serum pro-inflammatory cytokines and chemokine. Our study revealed a functional structure-activity relationship between andrographolide derivatives and innate immunity. We identified compound 3b as a potent immune suppressive agent with the potential to protect acute pulmonary infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Disease Models, Animal
  • Diterpenes / administration & dosage*
  • Diterpenes / chemical synthesis*
  • Diterpenes / chemistry
  • Diterpenes / pharmacology
  • Female
  • HeLa Cells
  • Humans
  • Immunity, Innate / drug effects*
  • Lipopolysaccharides / adverse effects
  • Mice
  • Molecular Structure
  • NF-kappa B / metabolism*
  • Phosphorylation / drug effects
  • Pneumonia / chemically induced
  • Pneumonia / prevention & control*
  • Signal Transduction / drug effects
  • Structure-Activity Relationship
  • THP-1 Cells

Substances

  • Diterpenes
  • Lipopolysaccharides
  • NF-kappa B
  • andrographolide