Danger-Associated Molecular Patterns (DAMPs): Molecular Triggers for Sterile Inflammation in the Liver

Int J Mol Sci. 2018 Oct 10;19(10):3104. doi: 10.3390/ijms19103104.

Abstract

Inflammatory liver diseases in the absence of pathogens such as intoxication by xenobiotics, cholestatic liver injury, hepatic ischemia-reperfusion injury (I/R), non-alcoholic steatohepatitis (NASH), or alcoholic liver disease (ALD) remain threatening conditions demanding specific therapeutic options. Caused by various different noxae, all these conditions have been recognized to be triggered by danger- or death-associated molecular patterns (DAMPs), discompartmentalized self-structures released by dying cells. These endogenous, ectopic molecules comprise proteins, nucleic acids, adenosine triphosphate (ATP), or mitochondrial compounds, among others. This review resumes the respective modes of their release-passively by necrotic hepatocytes or actively by viable or apoptotic parenchymal cells-and their particular roles in sterile liver pathology. It addresses their sensors and the initial inflammatory responses they provoke. It further addresses a resulting second wave of parenchymal death that might be of different mode, boosting the release of additional, second-line DAMPs. Thus, triggering a more complex and pronounced response. Initial and secondary inflammatory responses comprise the activation of Kupffer cells (KCs), the attraction and activation of monocytes and neutrophil granulocytes, and the induction of type I interferons (IFNs) and their effectors. A thorough understanding of pathophysiology is a prerequisite for identifying rational therapeutic targets.

Keywords: acetaminophen (APAP) intoxication; alcoholic liver disease (ALD); cholestasis; danger-associated molecular pattern (DAMP); hepatic ischemia-reperfusion (I/R); high mobility group box-1 (HMGB1); non-alcoholic steatohepatitis (NASH); sterile liver injury; type I interferon (IFN).

Publication types

  • Review

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Alarmins / genetics*
  • Alarmins / metabolism*
  • Animals
  • Biomarkers
  • HMGB1 Protein / genetics
  • HMGB1 Protein / metabolism
  • Hepatitis / genetics*
  • Hepatitis / metabolism*
  • Humans
  • Keratins / genetics
  • Keratins / metabolism
  • Mitochondria, Liver / metabolism
  • Pathogen-Associated Molecular Pattern Molecules / metabolism

Substances

  • Alarmins
  • Biomarkers
  • HMGB1 Protein
  • Pathogen-Associated Molecular Pattern Molecules
  • Keratins
  • Adenosine Triphosphate