title: Insights into the influence of 5-HT2c aminoacidic variants with the inhibitory action of serotonin inverse agonists and antagonists.
abstract: Specific modulation of serotonin 5-HT(2C) G protein-coupled receptors may be therapeutic for obesity and neuropsychiatric disorders. The different efficacy of drugs targeting these receptors are due to the presence of genetic variants in population and this variability is still hard to predict. Therefore, in order to administer the more suitable drug, taking into account patient genotype, it is necessary to know the molecular effects of its gene nucleotide variations. In this work, starting from an accurate 3D model of 5-HT(2C), we focus on the prediction of the possible effect of some single nucleotide polymorphisms (SNPs) producing amino acidic changes in proximity of the 5-HT(2C) ligand binding site. Particularly we chose a set of 5-HT(2C) inverse agonists and antagonists which have high inhibitory activity. After prediction of the structures of the receptor-ligand complexes using molecular docking tools, we performed full atom molecular dynamics simulations in explicit lipid bilayer monitoring the interactions between ligands and trans-membrane helices of the receptor, trying to infer relations with their biological activity. Serotonin, as the natural ligand was chosen as reference compound to advance a hypothesis able to explain the receptor inhibition mechanism. Indeed we observed a different behavior between the antagonists and inverse agonist with respect to serotonin or unbounded receptor, which could be responsible, even if not directly, of receptor's inactivation. Furthermore, we analyzed five aminoacidic variants of 5HT(2C) receptor observing alterations in the interactions between ligands and receptor which give rise to changes of free energy values for every complex considered.
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente- Università Politecnica delle Marche, via Brecce Bianche, 60128, Ancona, Italy, r.galeazzi@univpm.it.
authors.forename: Roberta
authors.initials: R
authors.lastname: Galeazzi
authors.forename: Luca
authors.initials: L
authors.lastname: Massaccesi
authors.forename: Francesco
authors.initials: F
authors.lastname: Piva
authors.forename: Giovanni
authors.initials: G
authors.lastname: Principato
authors.forename: Emilioano
authors.initials: E
authors.lastname: Laudadio
mesh_terms: D000596:Amino Acids / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D006801:Humans; D008024:Ligands; D008051:Lipid Bilayers / Q000378:metabolism; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D020641:Polymorphism, Single Nucleotide; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D044405:Receptor, Serotonin, 5-HT2C / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D058826:Serotonin 5-HT2 Receptor Agonists / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D058830:Serotonin 5-HT2 Receptor Antagonists / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D013816:Thermodynamics
chemical_list: D000596:Amino Acids; D008024:Ligands; D008051:Lipid Bilayers; D044405:Receptor, Serotonin, 5-HT2C; D058826:Serotonin 5-HT2 Receptor Agonists; D058830:Serotonin 5-HT2 Receptor Antagonists