3,4,5-trihydroxycinnamic acid inhibits lipopolysaccharide (LPS)-induced inflammation by Nrf2 activation in vitro and improves survival of mice in LPS-induced endotoxemia model in vivo

Mol Cell Biochem. 2014 May;390(1-2):143-53. doi: 10.1007/s11010-014-1965-y. Epub 2014 Jan 29.

Abstract

NF-E2-related factor 2 (Nrf2) has been demonstrated to be a key transcription factor regulating the anti-inflammatory genes including heme oxygenase-1 (HO-1) in experimental sepsis models. Based on the fact that 3,4,5-trihydorxycinnamic acid (THC) has been reported to possess anti-inflammatory properties in BV2 microglial cells, the possible effects of THC and its underlying mechanism was examined against lipopolysaccharide (LPS)-induced RAW 264.7 cell culture and septic mouse models. Pretreatment of RAW 264.7 cells with THC significantly attenuated LPS-induced NO, PGE2 production, and expression of iNOS and COX-2. THC also significantly suppressed LPS-induced release of pro-inflammatory cytokines and degradation of IκB-α. Increased phosphorylation of Nrf2 and nuclear translocation of Nrf2 were observed with THC treatment with consequent expression of HO-1. The data demonstrated that multiple signaling pathways including Akt, p38, and PKC are involved in the THC-induced activation of Nrf2/HO-1 pathway. Treatment of THC resulted in significantly increased survival of LPS-induced septic mice. THC also significantly ameliorated LPS-induced septic features such as hypothermia and increased vascular leakage. In accordance with the data from cell culture model, THC exhibited increased expression of HO-1 in kidney and decreased serum level of pro-inflammatory mediators such as TNF-α, IL-1β, and NO. Taken together, the present study for the first time demonstrates that THC inhibits inflammation in LPS-induced RAW264.7 cells by Nrf2 activation and improves survival of mice in LPS-induced endotoxemia model.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Disease Models, Animal
  • Endotoxemia / chemically induced
  • Endotoxemia / drug therapy*
  • Endotoxemia / metabolism*
  • Endotoxemia / pathology
  • Gallic Acid / administration & dosage
  • Gene Expression Regulation / drug effects
  • Humans
  • Inflammation / chemically induced
  • Inflammation / drug therapy*
  • Inflammation / metabolism
  • Lipopolysaccharides / toxicity
  • Mice
  • NF-E2-Related Factor 2 / biosynthesis*
  • NF-E2-Related Factor 2 / genetics
  • Signal Transduction / drug effects

Substances

  • Lipopolysaccharides
  • NF-E2-Related Factor 2
  • Nfe2l2 protein, mouse
  • Gallic Acid