Diacylglycerol lipases (DAGLα and DAGLβ) are responsible for the biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) in the brain and peripheral tissues. Selective DAGLβ inhibitors... Show moreDiacylglycerol lipases (DAGLα and DAGLβ) are responsible for the biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) in the brain and peripheral tissues. Selective DAGLβ inhibitors have been proposed as a potential treatment for inflammatory diseases with reduced potential for central nervous system (CNS) mediated side effects, but they are currently lacking. To develop DAGLβ selective inhibitors, a fluorescent biochemical assay was optimized and applied in a high-throughput screening (HTS) for DAGLβ. During the HTS, eight hits classified into four distinct chemotypes were identified. Subsequent structure-activity relationship (SAR) studies, focusing on hit 1 and its modifications, revealed a specific group as the modification hotspot crucial for achieving selectivity towards DAGLβ. Through an extensive SAR investigation, focusing on modifying this group, the first-in-class DAGLβ selective inhibitors, LEI-130 and LEI-131, were discovered. Following their discovery, LEI-130 and LEI-131 underwent comprehensive in vitro and in situ profiling studies. These investigations confirmed that LEI-130 and LEI-131 are selective and noncompetitive inhibitors of DAGLβ, effectively reducing inflammation. Show less
The endocannabinoid system (ECS) is a widespread modulatory system composed of cannabinoid receptors, endogenous signaling lipids termed endocannabinoids and the enzymes for the biosynthesis and... Show moreThe endocannabinoid system (ECS) is a widespread modulatory system composed of cannabinoid receptors, endogenous signaling lipids termed endocannabinoids and the enzymes for the biosynthesis and degradation of these endocannabinoids. It plays a crucial role in diverse (patho)physiological functions, such as neurotransmission, neural development, synaptic plasticity, mood, food intake, and inflammation. Enzymes involved in the biosynthesis (e. g. NAPE-PLD, DAGLs) and degradation (e. g. FAAH, MAGL) of endocannabinoids have attracted attention from both academia and industry due to their therapeutic potential. The discovery of selective inhibitors for these enzymes is important for functional assignment and biomedical applications. Activity-based protein profiling (ABPP) has emerged as a powerful technique, which to a large extend accelerated the development of selective inhibitors for ECS enzymes. This review summarizes the representative activity-based probes (ABPs) and small molecular inhibitors developed in the past two decades for ECS enzymes and will discuss the biological discoveries attributed by the application of these small molecules. Show less
