Endocannabinoid biosynthetic enzymes regulate pain response via LKB1-AMPK signaling

Proc Natl Acad Sci U S A. 2023 Dec 26;120(52):e2304900120. doi: 10.1073/pnas.2304900120. Epub 2023 Dec 18.

Abstract

Diacylglycerol lipase-beta (DAGLβ) serves as a principal 2-arachidonoylglycerol (2-AG) biosynthetic enzyme regulating endocannabinoid and eicosanoid metabolism in immune cells including macrophages and dendritic cells. Genetic or pharmacological inactivation of DAGLβ ameliorates inflammation and hyper-nociception in preclinical models of pathogenic pain. These beneficial effects have been assigned principally to reductions in downstream proinflammatory lipid signaling, leaving alternative mechanisms of regulation largely underexplored. Here, we apply quantitative chemical- and phospho-proteomics to find that disruption of DAGLβ in primary macrophages leads to LKB1-AMPK signaling activation, resulting in reprogramming of the phosphoproteome and bioenergetics. Notably, AMPK inhibition reversed the antinociceptive effects of DAGLβ blockade, thereby directly supporting DAGLβ-AMPK crosstalk in vivo. Our findings uncover signaling between endocannabinoid biosynthetic enzymes and ancient energy-sensing kinases to mediate cell biological and pain responses.

Keywords: AMPK; activity based protein profiling; diacylglycerol lipase; endocannabinoids; inflammation.

MeSH terms

  • AMP-Activated Protein Kinases / genetics
  • Arachidonic Acids / metabolism
  • Endocannabinoids* / metabolism
  • Glycerides* / metabolism
  • Humans
  • Lipoprotein Lipase / metabolism
  • Pain

Substances

  • Endocannabinoids
  • Glycerides
  • AMP-Activated Protein Kinases
  • Lipoprotein Lipase
  • Arachidonic Acids