Small Molecule Activation of NAPE-PLD Enhances Efferocytosis by Macrophages

N-Acyl-phosphatidylethanolamine hydrolyzingphospholipaseD (NAPE-PLD) is a zinc metallohydrolase that hydrolyzes N-acyl-phosphatidylethanolamines (NAPEs) to form N-acyl-ethanolamines (NAEs) and phosphatidic acid. Several lines ofevidence suggest that reduced NAPE-PLD activity could contribute tocardiometabolic diseases. For instance, NAPEPLD expressionis reduced in human coronary arteries with unstable atheroscleroticlesions, defective efferocytosis is implicated in the enlargementof necrotic cores of these lesions, and NAPE-PLD products such aspalmitoylethanolamide and oleoylethanolamide have been shown to enhanceefferocytosis. Thus, enzyme activation mediated by a small moleculemay serve as a therapeutic treatment for cardiometabolic diseases.As a proof-of-concept study, we sought to identify small moleculeactivators of NAPE-PLD. High-throughput screening followed by hitvalidation and primary lead optimization studies identified a seriesof benzothiazole phenylsulfonyl-piperidine carboxamides that variablyincreased activity of both mouse and human NAPE-PLD. From this setof small molecules, two NAPE-PLD activators (VU534 and VU533) were shown to increase efferocytosis by bone-marrowderived macrophages isolated from wild-type mice, while efferocytosiswas significantly reduced in Napepld (-/-) BMDM or after Nape-pld inhibition. Together, these studies demonstratean essential role for NAPE-PLD in the regulation of efferocytosisand the potential value of NAPE-PLD activators as a strategy to treatcardiometabolic diseases.

Automated summary

N-Acyl-phosphatidylethanolamine hydrolyzing phospholipase D (NAPE-PLD) is an enzyme that hydrolyzes N-acyl-phosphatidylethanolamines (NAPEs) to produce N-acyl-ethanolamines (NAEs) and phosphatidic acid. Reduced NAPE-PLD activity is associated with cardiometabolic diseases, and small molecule activators of NAPE-PLD could be a potential therapeutic treatment. A series of benzothiazole phenylsulfonyl-piperidine carboxamides were identified as NAPE-PLD activators, which increased efferocytosis by macrophages. These findings suggest the importance of NAPE-PLD in regulating efferocytosis and the potential use of NAPE-PLD activators for treating cardiometabolic diseases.