Targeting diacylglycerol lipase reduces alcohol consumption in preclinical models

Abstract

Alcohol use disorder (AUD) is associated with substantial morbidity, mortality, and societal cost, and pharmacological treatment options are limited. The endogenous cannabinoid (eCB) signaling system is critically involved in reward processing, and alcohol intake is positively correlated with release of the eCB ligand 2-arachidonoylglycerol (2-AG) within the reward neurocircuitry. Here we show that genetic and pharmacological inhibition of diacylglycerol lipase (DAGL), the rate-limiting enzyme in the synthesis of 2-AG, reduces alcohol consumption in a variety of preclinical mouse models, ranging from a voluntary free-access model to aversion-resistant drinking and dependence-like drinking induced via chronic intermittent ethanol vapor exposure. DAGL inhibition during either chronic alcohol consumption or protracted withdrawal did not elicit anxiogenic and depression-like behavioral effects. Last, DAGL inhibition also prevented ethanol-induced suppression of GABAergic transmission onto midbrain dopamine neurons, providing mechanistic insight into how DAGL inhibition could affect alcohol reward. These data suggest that reducing 2-AG signaling via inhibition of DAGL could represent an effective approach to reducing alcohol consumption across the spectrum of AUD severity.