Editorial [Hot Topic: Focus on Cannabinoids and Endocannabinoids (Guest Editor: Didier M. Lambert)]

Five years ago, a special issue of Current Medicinal Chemistry was published (Curr. Med. Chem., 1999, volume 6 issue number 8) and devoted to the “new trends in cannabinoid receptor ligands”. In the preface, the diversity in terms of chemical structures of cannabinoid ligands was highlighted. Five years later, the diversity is more present than ever. The number of compounds reported to act at the endocannabinoid system is impressive, the number of papers devoted to the cannabinoid targets is increasing. Up to date, two cannabinoid, G-protein coupled, receptors are unambiguously identified and characterised. The degradating processes involve a putative anandamide uptake protein as well as hydrolysing enzymes, two among these are also highly characterised : the fatty acid amide hydrolase and the monoacylglycerol lipase. They could constitute attractive targets and they were the subject of numerous reviews these two last years. Less has been written about the endocannabinoids synthesising enzymes. This second special issue devoted to the cannabinoids is divided in three chapters : The first one, entitled “Endocannabinoid-related Enzymes as Drug Targets with Special Reference to NAcylphosphatidylethanolamine- hydrolyzing Phospholipase D” written by Natsuo Ueda, Yasuo Okamoto and Kazuhito Tsuboi, gives an overview on the endocannabinoid system with an emphasis on the enzymes and more specially to the recently cloned anandamide synthesizing enzyme The second chapter “Recent Developments in the Medicinal Chemistry of Cannabimetic Indoles, Pyrroles and Indenes” by J. W. Huffman and L. W. Padgett, gives a comprehensive review of this interesting family of cannabinoid ligands. Finally, the last part is devoted to the “Current Knowledge on the Antagonists and Inverse Agonists of Cannabinoid Receptors” by G.G. Muccioli and D. M. Lambert. This chapter represents a review of the current scientific update of molecules presented in the scientific papers as well as in the patents. It describes antagonists and inverse agonists of both types of cannabinoid receptors and ends to the open field of the putative new cannabinoid receptors antagonists/inverse agonists.