Itaconate is an anti-inflammatory metabolite that activates Nrf2 via alkylation of KEAP1

Nature. 2018 Apr 5;556(7699):113-117. doi: 10.1038/nature25986. Epub 2018 Mar 28.

Abstract

The endogenous metabolite itaconate has recently emerged as a regulator of macrophage function, but its precise mechanism of action remains poorly understood. Here we show that itaconate is required for the activation of the anti-inflammatory transcription factor Nrf2 (also known as NFE2L2) by lipopolysaccharide in mouse and human macrophages. We find that itaconate directly modifies proteins via alkylation of cysteine residues. Itaconate alkylates cysteine residues 151, 257, 288, 273 and 297 on the protein KEAP1, enabling Nrf2 to increase the expression of downstream genes with anti-oxidant and anti-inflammatory capacities. The activation of Nrf2 is required for the anti-inflammatory action of itaconate. We describe the use of a new cell-permeable itaconate derivative, 4-octyl itaconate, which is protective against lipopolysaccharide-induced lethality in vivo and decreases cytokine production. We show that type I interferons boost the expression of Irg1 (also known as Acod1) and itaconate production. Furthermore, we find that itaconate production limits the type I interferon response, indicating a negative feedback loop that involves interferons and itaconate. Our findings demonstrate that itaconate is a crucial anti-inflammatory metabolite that acts via Nrf2 to limit inflammation and modulate type I interferons.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkylation
  • Animals
  • Anti-Inflammatory Agents / metabolism*
  • Anti-Inflammatory Agents / pharmacology*
  • Carboxy-Lyases
  • Cattle
  • Cysteine / chemistry
  • Cysteine / metabolism
  • Cytokines / biosynthesis
  • Cytokines / immunology
  • Feedback, Physiological
  • Female
  • HEK293 Cells
  • Humans
  • Hydro-Lyases / biosynthesis
  • Interferon-beta / immunology
  • Interferon-beta / pharmacology
  • Kelch-Like ECH-Associated Protein 1 / chemistry*
  • Kelch-Like ECH-Associated Protein 1 / metabolism*
  • Lipopolysaccharides / immunology
  • Lipopolysaccharides / pharmacology
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Mice
  • NF-E2-Related Factor 2 / agonists*
  • NF-E2-Related Factor 2 / metabolism*
  • Proteins / metabolism
  • Rats
  • Rats, Wistar
  • Succinates / chemistry
  • Succinates / metabolism*

Substances

  • Anti-Inflammatory Agents
  • Cytokines
  • KEAP1 protein, human
  • Keap1 protein, mouse
  • Kelch-Like ECH-Associated Protein 1
  • Lipopolysaccharides
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Nfe2l2 protein, mouse
  • Proteins
  • Succinates
  • Interferon-beta
  • ACOD1 protein, human
  • Carboxy-Lyases
  • Hydro-Lyases
  • Irg1 protein, mouse
  • Cysteine
  • itaconic acid