In Vivo Characterization of the Ultrapotent Monoacylglycerol Lipase Inhibitor {4-[bis-(benzo[d][1,3]dioxol-5-yl)methyl]-piperidin-1-yl}(1H-1,2,4-triazol-1-yl)methanone (JJKK-048).

Monoacylglycerol lipase (MAGL) is a serine hydrolase that acts as a principal degradative enzyme for the endocannabinoid 2-arachidonoylglycerol (2-AG). In addition to terminating the signaling function of 2-AG, MAGL liberates arachidonic acid to be used as a primary source for neuroinflammatory prostaglandin synthesis in the brain. MAGL activity also contributes to cancer pathogenicity by producing precursors for tumor-promoting bioactive lipids. Pharmacological inhibitors of MAGL provide valuable tools for characterization of MAGL and 2-AG signaling pathways. They also hold great therapeutic potential to treat several pathophysiological conditions, such as pain, neurodegenerative disorders, and cancer. We have previously reported piperidine triazole urea, {4-[bis-(benzo[d][1,3]dioxol-5-yl)methyl]-piperidin-1-yl}(1H-1,2,4-triazol-1-yl)methanone (JJKK-048), to be an ultrapotent and highly selective inhibitor of MAGL in vitro. Here, we characterize in vivo effects of JJKK-048. Acute in vivo administration of JJKK-048 induced a massive increase in mouse brain 2-AG levels without affecting brain anandamide levels. JJKK-048 appeared to be extremely potent in vivo. Activity-based protein profiling revealed that JJKK-048 maintains good selectivity toward MAGL over other serine hydrolases. Our results are also the first to show that JJKK-048 promoted significant analgesia in a writhing test with a low dose that did not cause cannabimimetic side effects. At a high dose, JJKK-048 induced analgesia both in the writhing test and in the tail-immersion test, as well as hypomotility and hyperthermia, but not catalepsy.

Potent and selective N-(4-sulfamoylphenyl)thiourea-based GPR55 agonists.

To date, many known G protein-coupled receptor 55 (GPR55) ligands are those identified among the cannabinoids. In order to further study the function of GPR55, new potent and selective ligands are needed. In this study, we utilized the screening results from PubChem bioassay AID 1961 which reports the results of Image-based HTS for Selective Agonists of GPR55. Three compounds, CID1792579, CID1252842 and CID1011163, were further evaluated and used as a starting point to create a series of nanomolar potency GPR55 agonists with N-(4-sulfamoylphenyl)thiourea scaffold. The GPR55 activity of the compounds were screened by using a commercial ß-arrestin PathHunter assay and the potential compounds were further evaluated by using a recombinant HEK cell line exhibiting GPR55-mediated effects on calcium signalling. The designed compounds were not active when tested against various endocannabinoid targets (CB1R, CB2R, FAAH, MGL, ABHD6 and ABHD12), indicating compounds' selectivity for the GPR55. Finally, structure-activity relationships of these compounds were explored.