Endocannabinoid biosynthetic enzymes regulate pain response via LKB1-AMPK signaling

Diacylglycerol lipase-beta (DAGLB) 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 DAGLb ameliorates inflammation and hyper-nociception in preclinical models of pathogenic pain. These beneficial effects have been assigned principally to reductions in downstream pro-inflammatory lipid signaling, leaving alternative mechanisms of regulation largely underexplored. Here, we apply quantitative chemical- and phospho-proteomics to discover that disruption of DAGLb 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 DAGLb blockade, thereby directly supporting DAGLß-AMPK crosstalk in vivo. Our findings uncover signaling between endocannabinoid biosynthetic enzymes and ancient energy sensing kinases to mediate cell biological and pain responses. Overall design: Test the mRNA levels in DAGLB KO and WT cells. Both cells were further stimulated with LPS (PBS as vehicle). Cell resources are bone marrow derived macrophages from DAGLB WT and KO mice.