cAMP metabolism controls caspase-11 inflammasome activation and pyroptosis in sepsis

Sci Adv. 2019 May 22;5(5):eaav5562. doi: 10.1126/sciadv.aav5562. eCollection 2019 May.

Abstract

The ability of cytosolic lipopolysaccharide (LPS) to activate caspase-11-dependent nonclassical inflammasome is intricately controlled to avoid excessive inflammatory responses. However, very little is known about the regulatory role of various metabolic pathways in the control of caspase-11 activation. Here, we demonstrate that l-adrenaline can act on receptor ADRA2B to inhibit the activation of the caspase-11 inflammasome by cytosolic LPS or Escherichia coli infection in macrophages. l-adrenaline-induced cAMP production via the enzyme ADCY4 promotes protein kinase A (PKA) activation, which then blocks the caspase-11-mediated proteolytic maturation of interleukin-1β, gasdermin D (GSDMD) cleavage, and consequent DAMP release. Inhibition of PDE8A-mediated cAMP hydrolysis limits caspase-11 inflammasome activation and pyroptosis in macrophages. Consequently, pharmacological modulation of the ADRA2B-ADCY4-PDE8A-PKA axis, knockout of caspase-11 (Casp11-/- ), or Gsdmd inactivation (GsdmdI105N/I105N ) similarly protects against LPS-induced lethality in poly(I:C)-primed mice. Our results provide previously unidentified mechanistic insight into immune regulation by cAMP and represent a proof of concept that immunometabolism constitutes a potential therapeutic target in sepsis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenylyl Cyclases / metabolism
  • Animals
  • Caspases / metabolism
  • Caspases, Initiator / metabolism*
  • Cell Survival
  • Cyclic AMP / metabolism*
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Enzyme Activation
  • Escherichia coli / metabolism
  • Female
  • Humans
  • Hydrolysis
  • Inflammasomes*
  • Inflammation
  • Lipopolysaccharides
  • Macrophages / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Monocytes / metabolism
  • Phosphorylation
  • Pyroptosis*
  • Receptors, Adrenergic, alpha-2 / metabolism
  • Sepsis / physiopathology*
  • Shock, Septic
  • THP-1 Cells

Substances

  • ADRA2B protein, human
  • Adra2b protein, mouse
  • Inflammasomes
  • Lipopolysaccharides
  • Receptors, Adrenergic, alpha-2
  • Cyclic AMP
  • Cyclic AMP-Dependent Protein Kinases
  • Casp4 protein, mouse
  • Caspases
  • Caspases, Initiator
  • caspase 11, human
  • Adenylyl Cyclases
  • adenylyl cyclase 4