Specific Aim: New 5HT2AR/14-3-3 isoform signal pathway identification and assay development for discovering psychoplastogenic compounds. Significance: Emerging data and limited clinical results show the promise of psychedelic drugs in the durable relief of people from seemingly untreatable psychiatric disorders and drug addictions. Neuroimaging evidence supports the concept that the brain after a psychedelic treatment becomes more flexible or `plastic', which is thought to be a component of its putative therapeutic effects. However, the side effects of psychedelics can be dangerous or even deadly. To develop new therapeutic options, we need to understand psychedelics underlying mechanisms of action. Many psychedelics act on the 5-HT2A serotonin receptor (5HT2AR), a G-protein Coupled Receptor (GPCR), to exert their effects. G-protein and ß-arrestin signaling pathways cannot distinguish therapeutic and side effects of psychedelics. Importantly, the 5HT2AR antagonist ketanserin, can promote receptor endocytosis and still derive equivalent relief from depression-associated behaviors in mice, suggesting trafficking plays an important role. We studied GPCR/14-3-3 signal adaptor interactions using the LinkLight technology and found that GPCR/14-3-3 signals are closely related to receptor trafficking. Thus, studying 5HT2AR/14-3-3 signals mediated by psychedelics should shed light on understanding molecular mechanisms that contribute to psychedelic and therapeutic benefits, and develop new psychoplastogenic compounds. We have developed 5HT2AR/14-3-3ε and 5HT2AR/14-3-3γ LinkLight assays. We plan to develop additional 5HT2AR/14-3-3 isoform assays including 14-3-3ß and 14-3-3ζ since a GPCR can differentially and temporally engage with 14-3-3 isoforms. Different 14-3-3 isoforms could display different functions. We plan to profile a panel of psychedelics in 5HT2AR/14-3-3 isoform assays and see if we can connect signaling pathways to physiological functions. In addition, we want to conduct a pilot screen to find compounds biased to the 14-3-3 signaling pathway without G-protein signals. Such biased compounds could lead us to better understand psychedelics' underlying mechanisms of action and develop new psychoplastogenic compounds. Experimental Design: Task 1. Develop additional 5HT2AR/14-3-3ß and 5HT2AR/14-3-3ζ assays, profile 5HT2AR/14-3-3 isoform (ε, γ, ß, & ζ) pathways with a panel of psychedelics including hallucinogenic and non- hallucinogenic agonists, as well as antagonists, and differentially and temporally characterize 5HT2AR/14-3-3 isoform signals. Task 2. Identify pathway-biased ligands by conducting a pilot screen with an in-house GPCR-focused library and characterize hits activities in 5HT2AR/14-3-3 isoforms, G-protein and ß-arrestin pathway assays. Next Phase Plan: We expect to find multi-pathway biased ligands based on our results of screens using opioid receptor/14- 3-3 assays (unpublished results). These multi-pathway biased ligands will be evaluated for preliminary toxicity and DMPK activities and for in vivo rodent behavior tests and neuroimaging. The proof of concept studies will enable us to partner with potential collaborators to accelerate drug development.
Public Health Relevance Statement: Narrative Emerging data and limited clinical results showed the promise of psychedelic drugs in the durable relief of people from seemly untreatable psychiatric disorders and drug use disorders. Many these psychedelic drugs act on the 5-HT2A serotonin receptor (5HT2AR), a G-protein Coupled Receptor (GPCR). It is believed that psychedelics act on 5HT2AR to make neuron more plastic to exert putative therapeutic effects. However, the underlying molecular mechanisms of 5HT2AR is not clear. If we are to develop improved alternatives to psychedelics for treating neuropsychiatric diseases, we should characterize a new 5HT2AR/14-3-3 signaling pathways, given the roles of 14-3-3 proteins participated in neuroplasiticity. We propose to characterize the 5HT2AR/14-3-3 pathway as a new drug target and identify pathway-biased ligands that could lead us to develop new psychoplastogenic compounds.
Project Terms: Acceleration; After Care; After-Treatment; post treatment; Aftercare; Behavior; Mental disorders; Mental health disorders; Psychiatric Disease; Psychiatric Disorder; mental illness; psychiatric illness; psychological disorder; Biological Assay; Assay; Bioassay; Biologic Assays; Brain; Brain Nervous System; Encephalon; Cell physiology; Cell Function; Cell Process; Cellular Function; Cellular Physiology; Cellular Process; Subcellular Process; Cerebral cortex; Dangerousness; Mental Depression; depression; Drug Use Disorder; Endocytosis; Enzymes; Enzyme Gene; Experimental Designs; Hallucinogens; Hallucinogenic Agents; Hallucinogenic Drugs; Hallucinogenic Substances; Psychedelic Agents; Psychedelics; Psychotomimetic Agents; psychedelic drug; psychotomimetic drug; Ketanserin; Libraries; Ligands; Mental Health; Mental Hygiene; Psychological Health; Mus; Mice; Mice Mammals; Murine; Persons; Neuronal Plasticity; CNS plasticity; central nervous system plasticity; neural plasticity; neuroplastic; neuroplasticity; Neurons; Nerve Cells; Nerve Unit; Neural Cell; Neurocyte; neuronal; Phosphotransferases; Kinases; Phosphotransferase Gene; Transphosphorylases; Play; Protein Kinase; ATP-protein phosphotransferase; Kinase Family Gene; glycogen synthase a kinase; hydroxyalkyl protein kinase; phosphorylase b kinase kinase; Proteins; Opioid Receptor; Opiate Receptors; serotonin receptor; 5-HT Receptors; 5-Hydroxytryptamine Receptors; Research; Rodent; Rodentia; Rodents Mammals; Role; social role; Serotonin Antagonists; 5-HT Antagonists; 5-Hydroxytryptamine Antagonists; 5HT antagonists; Antiserotonergic Agents; Serotonin Blockaders; Serotonin Receptor Antagonist; Signal Pathway; Signal Transduction; Cell Communication and Signaling; Cell Signaling; Intracellular Communication and Signaling; Signal Transduction Systems; Signaling; biological signal transduction; Technology; Therapeutic Equivalency; Bioequivalence; Clinical Equivalency; Generic Equivalency; drug bioequivalence; drug bioequivalent; transcription factor; Basal Transcription Factor; Basal transcription factor genes; General Transcription Factor Gene; General Transcription Factors; Transcription Factor Proto-Oncogene; Transcription factor genes; G-Proteins; GTP-Regulatory Proteins; Guanine Nucleotide Coupling Protein; Guanine Nucleotide Regulatory Proteins; GTP-Binding Proteins; Mediating; arrestin B; ß-arrestin; beta-arrestin; improved; Clinical; Phase; Physiologic; Physiological; Neurological; Neurologic; Link; insight; Agonist; Therapeutic; Scientist; Complex; Location; interest; experience; Protein Isoforms; Isoforms; receptor; Receptor Protein; receptor mediated endocytosis; synaptogenesis; synapse formation; Chromosome Pairing; Chromosomal Synapsis; Synapsis; trafficking; Toxic effect; Toxicities; neuroimaging; neural imaging; neuro-imaging; neurological imaging; G-Protein-Coupled Receptors; G Protein-Complex Receptor; G Protein-Coupled Receptor Genes; GPCR; behavior test; behavioral test; drug action; assay development; drug development; Dendritic Spines; dendrite spine; drug discovery; Molecular Interaction; Binding; Signaling Protein; Signaling Factor Proto-Oncogene; Signaling Pathway Gene; HTR2A gene; 5-HT-2A Gene; 5-HT2A; 5-Hydroxytryptamine (Serotonin) Receptor 2A Gene; 5-Hydroxytryptamine Receptor 2A; 5-Hydroxytryptamine Receptor 2A Gene; HTR2; HTR2 Gene; HTR2A; Serotonin 5-HT-2 Receptor Gene; Serotonin 5-HT-2A Receptor; Drug Addiction; Chemical Dependence; Drug Dependence; Drug Dependency; Affinity; Data; Receptor Signaling; in vivo; G Protein-Coupled Receptor Signaling; GPCR Signaling; Neuronal Differentiation; Screening Result; Molecular; Therapeutic Effect; Health Professional; Health Care Professional; Healthcare professional; Pathway interactions; pathway; neurite growth; new drug treatments; new drugs; new pharmacological therapeutic; new therapeutics; new therapy; next generation therapeutics; novel drug treatments; novel drugs; novel pharmaco-therapeutic; novel pharmacological therapeutic; novel therapy; novel therapeutics; therapeutic agent development; therapeutic development; new drug target; new druggable target; new pharmacotherapy target; new therapy target; novel drug target; novel druggable target; novel pharmacotherapy target; novel therapeutic target; novel therapy target; new therapeutic target; flexible; flexibility; neuropsychiatric disease; neuropsychiatric disorder; opiate consumption; opiate drug use; opiate intake; opiate use; opioid consumption; opioid drug use; opioid intake; opioid use; Drug Screening; side effect; antagonist; antagonism; pharmacologic
