There is compelling evidence that activation of brain serotonin 5HT2C G protein-coupled receptors (GPCRs) produces anti-obesity effects in humans, attenuation of psychomimetic activity, and other neuropsychiatric effects. Meanwhile, activation of brain 5HT2A GPCRs produces psychomimetic effects and activation of peripheral 5HT2B GPCRs produces cardiac valvulopathy and pulmonary hypertension. Currently, there is no 5HT2C receptor agonist reported that does not also activate 5HT2A and/or 5HT2B receptors. This research proposes to exploit a compound synthesized in our lab, (1R,3S)-(-)-trans-1-phenyl-3-dimethylamino-1,2,3,4- tetrahydronaphthalene (PAT), that is a full-efficacy agonist at human 5HT2C receptors, plus, it is an antagonist at 5HT2A and 5HT2B receptors. As a small (MW=250) lipophilic molecule, (-)-trans-PAT readily penetrates mouse brain after peripheral (IP) administration to inhibit food consumption, produce weight loss, and inhibit amphetamine-induced locomotion, neurobehavioral effects consistent with 5HT2C agonism and 5HT2A antagonism. This research proposes preclinical evaluation of (-)-trans-PAT as pharmacotherapy for obesity and neuropsychiatric disorders, and, synthesis of other PATs with potent and efficacious 5HT2C agonist activity;PATs with potent 5HT2A/5HT2B antagonism may be lead drugs for psychiatric or cardiovascular diseases. We also have identified a potent PAT-type 5HT2C inverse agonist useful especially to characterize molecular determinants involved in ligand-directed 5HT2C function. Targeted medicinal chemical syntheses will provide PAT type stereo-probes as test drugs for preclincial evaluation and to map molecular determinants for 5HT2C binding/activation for inferences of receptor 3D structure. Forty PATs already are available and 32 new analogs will help delineate the PAT- 5HT2C pharmacophore - the optimal PAT steric, lipophilic, and electronic chemical molecular features. In vitro binding/functional studies will continue to be conducted using clonal cells expressing recombinant human 5HT2A, 5HT2B, or 5HT2C receptors - preliminary results and PAT-5HT2C 3D QSAR and receptor homology models lead us to propose construction and expression of D3.32A, S3.36A, A5.46N, A5.46S, F5.47A, F5.48A, W6.48A, F6.51A, F6.52A, Y7.43A, &Y7.53A point-mutated 5HT2C receptors to validate hypothesized PAT- 5HT2C binding/function interactions. In an iterative fashion, pharmacological results and molecular models generate additional hypotheses to test involving additional PAT syntheses and 5HT2C point-mutations for receptor characterization and development of PAT-type 5HT2C agonist drug structures. Preclinical studies to evaluate PATs as pharmacotherapy for obesity, eating and other neuropsychiatric disorders, as well as, to determine in vivo molecular mechanisms of action, are conducted using wild-type vs. genetically modified mice with global disruption (""""""""knock-out"""""""") of 5HT2C and 5HT2A receptor signaling.

Public Health Relevance

About 65% of adults and 16% of children aged 6-19 years in the U.S. currently (2005) are overweight or obese. Obesity is associated with increased risk for cardiovascular disease;diabetes;certain forms of cancer, depression, and various other physical, psychological, and social morbidities. Current pharmacotherapy available for obesity is unsatisfactory. This research seeks to develop new drugs to treat obesity, as well as, certain neuropsychiatric disorders.

National Institute of Health (NIH)
National Institute of Mental Health (NIMH)
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Molecular Neuropharmacology and Signaling Study Section (MNPS)
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Winsky, Lois M
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University of Florida
Schools of Pharmacy
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Liu, Yue; Canal, Clinton E; Cordova-Sintjago, Tania C et al. (2017) Mutagenesis Analysis Reveals Distinct Amino Acids of the Human Serotonin 5-HT2C Receptor Underlying the Pharmacology of Distinct Ligands. ACS Chem Neurosci 8:28-39
Sakhuja, Rajeev; Kondabolu, Krishnakanth; Córdova-Sintjago, Tania et al. (2015) Novel 4-substituted-N,N-dimethyltetrahydronaphthalen-2-amines: synthesis, affinity, and in silico docking studies at serotonin 5-HT2-type and histamine H1 G protein-coupled receptors. Bioorg Med Chem 23:1588-600
Kasper, James M; Booth, Raymond G; Peris, Joanna (2015) Serotonin-2C receptor agonists decrease potassium-stimulated GABA release in the nucleus accumbens. Synapse 69:78-85
Canal, Clinton E; Felsing, Daniel E; Liu, Yue et al. (2015) An Orally Active Phenylaminotetralin-Chemotype Serotonin 5-HT7 and 5-HT1A Receptor Partial Agonist that Corrects Motor Stereotypy in Mouse Models. ACS Chem Neurosci 6:1259-70
Córdova-Sintjago, Tania; Villa, Nancy; Fang, Lijuan et al. (2014) Aromatic interactions impact ligand binding and function at serotonin 5-HT2C G protein-coupled receptors: Receptor homology modeling, ligand docking, and molecular dynamics results validated by experimental studies. Mol Phys 112:398-407
Canal, Clinton E; Morgan, Drake; Felsing, Daniel et al. (2014) A novel aminotetralin-type serotonin (5-HT) 2C receptor-specific agonist and 5-HT2A competitive antagonist/5-HT2B inverse agonist with preclinical efficacy for psychoses. J Pharmacol Exp Ther 349:310-8
Canal, Clinton E; Cordova-Sintjago, Tania; Liu, Yue et al. (2013) Molecular pharmacology and ligand docking studies reveal a single amino acid difference between mouse and human serotonin 5-HT2A receptors that impacts behavioral translation of novel 4-phenyl-2-dimethylaminotetralin ligands. J Pharmacol Exp Ther 347:705-16
Morgan, Drake; Kondabolu, Krishnakanth; Kuipers, Allison et al. (2013) Molecular and behavioral pharmacology of two novel orally-active 5HT2 modulators: potential utility as antipsychotic medications. Neuropharmacology 72:274-81
Canal, Clinton E; Booth, Raymond G; Morgan, Drake (2013) Support for 5-HT2C receptor functional selectivity in vivo utilizing structurally diverse, selective 5-HT2C receptor ligands and the 2,5-dimethoxy-4-iodoamphetamine elicited head-twitch response model. Neuropharmacology 70:112-21
Kasper, James; Tikamdas, Rajiv; Kim, Myong Sang et al. (2013) The serotonin-2 receptor modulator, (-)-trans-PAT, decreases voluntary ethanol consumption in rats. Eur J Pharmacol 718:98-104

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