Structural basis of selective cannabinoid CB2 receptor activation

Cannabinoid CB2 receptor (CB2R) agonists are investigated as therapeutic agents in the clinic. However, their molecular mode-of-action is not fully understood. Here, we report the discovery of LEI-102, a CB2R agonist, used in conjunction with three other CBR ligands (APD371, HU308, and CP55,940) to investigate the selective CB2R activation by binding kinetics, site-directed mutagenesis, and cryo-EM studies. We identify key residues for CB2R activation. Highly lipophilic HU308 and the endocannabinoids, but not the more polar LEI-102, APD371, and CP55,940, reach the binding pocket through a membrane channel in TM1-TM7. Favorable physico-chemical properties of LEI-102 enable oral efficacy in a chemotherapy-induced nephropathy model. This study delineates the molecular mechanism of CB2R activation by selective agonists and highlights the role of lipophilicity in CB2R engagement. This may have implications for GPCR drug design and sheds light on their activation by endogenous ligands. Cannabinoid CB2 receptor (CB2R) agonists are investigated as therapeutic agents in the clinic. Here, authors report the discovery of LEI-102, a CB2R agonist, used in conjunction with three other CBR ligands (APD371, HU308, and CP55,940) to investigate selective CB2R activation.

Automated summary

In this study, the authors report the discovery of a CB2R agonist, LEI-102, and investigate its selective activation of CB2R in conjunction with three other CBR ligands (APD371, HU308, and CP55,940). They identify key residues for CB2R activation and reveal the important role of lipophilicity in CB2R engagement. The favorable physico-chemical properties of LEI-102 enable its oral efficacy in a chemotherapy-induced nephropathy model.