Biomaterial Database

Enantiospecific Allosteric Modulation of Cannabinoid 1 Receptor. 2017

Robert B Laprairie, and Pushkar M Kulkarni, and Jeffrey R Deschamps, and Melanie E M Kelly, and David R Janero, and Maria G Cascio, and Lesley A Stevenson, and Roger G Pertwee, and Terrence P Kenakin, and Eileen M Denovan-Wright, and Ganesh A Thakur

The cannabinoid 1 receptor (CB1R) is one of the most widely expressed metabotropic G protein-coupled receptors in brain, and its participation in various (patho)physiological processes has made CB1R activation a viable therapeutic modality. Adverse psychotropic effects limit the clinical utility of CB1R orthosteric agonists and have promoted the search for CB1R positive allosteric modulators (PAMs) with the promise of improved drug-like pharmacology and enhanced safety over typical CB1R agonists. In this study, we describe the synthesis and in vitro and ex vivo pharmacology of the novel allosteric CB1R modulator GAT211 (racemic) and its resolved enantiomers, GAT228 (R) and GAT229 (S). GAT211 engages CB1R allosteric site(s), enhances the binding of the orthosteric full agonist [3H]CP55,490, and reduces the binding of the orthosteric antagonist/inverse agonist [3H]SR141716A. GAT211 displayed both PAM and agonist activity in HEK293A and Neuro2a cells expressing human recombinant CB1R (hCB1R) and in mouse-brain membranes rich in native CB1R. GAT211 also exhibited a strong PAM effect in isolated vas deferens endogenously expressing CB1R. Each resolved and crystallized GAT211 enantiomer showed a markedly distinctive pharmacology as a CB1R allosteric modulator. In all biological systems examined, GAT211's allosteric agonist activity resided with the R-(+)-enantiomer (GAT228), whereas its PAM activity resided with the S-(-)-enantiomer (GAT229), which lacked intrinsic activity. These results constitute the first demonstration of enantiomer-selective CB1R positive allosteric modulation and set a precedent whereby enantiomeric resolution can decisively define the molecular pharmacology of a CB1R allosteric ligand.

UI	MeSH Term	Description	Entries
D007211	Indoles	Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.
D007536	Isomerism	The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)	Isomerisms
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000494	Allosteric Regulation	The modification of the reactivity of ENZYMES by the binding of effectors to sites (ALLOSTERIC SITES) on the enzymes other than the substrate BINDING SITES.	Regulation, Allosteric,Allosteric Regulations,Regulations, Allosteric
D000495	Allosteric Site	A site on an enzyme which upon binding of a modulator, causes the enzyme to undergo a conformational change that may alter its catalytic or binding properties.	Allosteric Sites,Site, Allosteric,Sites, Allosteric
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D043884	Receptor, Cannabinoid, CB1	A subclass of cannabinoid receptor found primarily on central and peripheral NEURONS where it may play a role modulating NEUROTRANSMITTER release.	Cannabinoid Receptor CB1,CB1 Receptor,Receptor CB1, Cannabinoid,Receptor, CB1
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus
D057809	HEK293 Cells	A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.	293T Cells,HEK 293 Cell Line,HEK 293 Cells,Human Embryonic Kidney Cell Line 293,Human Kidney Cell Line 293,293 Cell, HEK,293 Cells, HEK,293T Cell,Cell, 293T,Cell, HEK 293,Cell, HEK293,Cells, 293T,Cells, HEK 293,Cells, HEK293,HEK 293 Cell,HEK293 Cell
D063386	Cannabinoid Receptor Agonists	Compounds that interact with and stimulate the activity of CANNABINOID RECEPTORS.	Cannabinoid Agonist,Cannabinoid Receptor Agonist,Cannabinoid Agonists,Cannabinoid Receptor Activators,Activators, Cannabinoid Receptor,Agonist, Cannabinoid,Agonist, Cannabinoid Receptor,Agonists, Cannabinoid,Agonists, Cannabinoid Receptor,Receptor Activators, Cannabinoid,Receptor Agonist, Cannabinoid,Receptor Agonists, Cannabinoid