Stimulation of soluble guanylate cyclase exerts antiinflammatory actions in the liver through a VASP/NF-κB/NLRP3 inflammasome circuit

Proc Natl Acad Sci U S A. 2020 Nov 10;117(45):28263-28274. doi: 10.1073/pnas.2000466117. Epub 2020 Oct 26.

Abstract

Soluble guanylate cyclase (sGC) catalyzes the conversion of guanosine triphosphate into cyclic guanosine-3',5'-monophosphate, a key second messenger in cell signaling and tissue homeostasis. It was recently demonstrated that sGC stimulation is associated with a marked antiinflammatory effect in the liver of mice with experimental nonalcoholic steatohepatitis (NASH). Here, we investigated the mechanisms underlying the antiinflammatory effect of the sGC stimulator praliciguat (PRL) in the liver. Therapeutic administration of PRL exerted antiinflammatory and antifibrotic actions in mice with choline-deficient l-amino acid-defined high-fat diet-induced NASH. The PRL antiinflammatory effect was associated with lower F4/80- and CX3CR1-positive macrophage infiltration into the liver in parallel with lower Ly6CHigh- and higher Ly6CLow-expressing monocytes in peripheral circulation. The PRL antiinflammatory effect was also associated with suppression of hepatic levels of interleukin (IL)-1β, NLPR3 (NACHT, LRR, and PYD domain-containing protein 3), ASC (apoptosis-associated speck-like protein containing a caspase-recruitment domain), and active cleaved-caspase-1, which are components of the NLRP3 inflammasome. In Kupffer cells challenged with the classical inflammasome model of lipopolysaccharide plus adenosine triphosphate, PRL inhibited the priming (expression of Il1b and Nlrp3) and blocked the release of mature IL-1β. Mechanistically, PRL induced the protein kinase G (PKG)-mediated phosphorylation of the VASP (vasodilator-stimulated phosphoprotein) Ser239 residue which, in turn, reduced nuclear factor-κB (NF-κB) activity and Il1b and Nlrp3 gene transcription. PRL also reduced active cleaved-caspase-1 levels independent of pannexin-1 activity. These data indicate that sGC stimulation with PRL exerts antiinflammatory actions in the liver through mechanisms related to a PKG/VASP/NF-κB/NLRP3 inflammasome circuit.

Keywords: Kupffer cells; inflammation; liver; soluble guanylate cyclase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / metabolism
  • Anti-Inflammatory Agents / pharmacology
  • Antigens, Ly / metabolism
  • CX3C Chemokine Receptor 1 / metabolism
  • Caspase 1 / metabolism
  • Cell Adhesion Molecules / metabolism*
  • Inflammasomes / metabolism*
  • Interleukin-1beta / metabolism
  • Kupffer Cells / metabolism
  • Lipopolysaccharides
  • Liver / metabolism*
  • Macrophages / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Microfilament Proteins / metabolism*
  • NF-kappa B / metabolism*
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism*
  • Non-alcoholic Fatty Liver Disease / metabolism
  • Phosphoproteins / metabolism*
  • Soluble Guanylyl Cyclase / metabolism*
  • Soluble Guanylyl Cyclase / pharmacology

Substances

  • Anti-Inflammatory Agents
  • Antigens, Ly
  • CX3C Chemokine Receptor 1
  • Cell Adhesion Molecules
  • Cx3cr1 protein, mouse
  • IL1B protein, mouse
  • Inflammasomes
  • Interleukin-1beta
  • Lipopolysaccharides
  • Ly-6C antigen, mouse
  • Microfilament Proteins
  • NF-kappa B
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Phosphoproteins
  • vasodilator-stimulated phosphoprotein
  • Caspase 1
  • Soluble Guanylyl Cyclase