Ketamine induces synaptic and monoaminergic remodeling in human iPSC-derived neurons
Carlo Sala, Jessica Pagano, Eleonora Mangano, Sofia Eminente, Matteo Marcatili, Michaela Krivosova, Viviana Tritto, Roberta Bordoni, Tobias Boeckers, Luciano Conti
preprint DOI: 10.21203/rs.3.rs-9096293/v1 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Laboratory study |
|---|---|
| Population | Human induced pluripotent stem cell (hiPSC)-derived forebrain neurons |
| Intervention | Ketamine |
| Dose | 1 µM |
| Duration | 72 hours |
| Topics | Esketamine Ketamine |
| Key points | Ketamine increased synaptic localization of PSD-95, modulated the Akt pathway, and altered expression of 604 genes, upregulating monoamine-related genes (DDC, DRD1) and downregulating genes for GPCR ligand binding and neurotransmitter transport, without changing BDNF levels or MAPK activation. |
Abstract
Abstract Major depressive disorder (MDD) is a leading cause of global disability, and a substantial proportion of patients develop treatment-resistant depression (TRD), highlighting the urgent need for mechanistically novel and fast-acting antidepressants. Ketamine has emerged as a paradigm-shifting therapy due to its rapid and robust antidepressant effects, yet its molecular mechanisms in human neurons remain incompletely understood. Here, we investigated the cellular and transcriptomic effects of ketamine in human induced pluripotent stem cell (hiPSC)-derived forebrain neurons. Neuronal cultures were treated with ketamine (1 µM) for 72 hours and analyzed using immunocytochemistry, western blotting, and RNA sequencing. Ketamine treatment did not alter gross neuronal morphology or presynaptic organization but significantly increased synaptic localization of the postsynaptic scaffolding protein PSD-95, suggesting rapid functional strengthening of existing excitatory synapses. At the signaling level, ketamine selectively modulated the Akt pathway without inducing changes in BDNF protein levels or MAPK activation, and without broadly altering excitatory or inhibitory synaptic protein expression. Transcriptomic profiling revealed 604 differentially expressed genes, with significant enrichment of pathways related to serotonergic and dopaminergic neurotransmission. Notably, ketamine upregulated genes involved in monoamine synthesis and signaling, including DDC and DRD1 , while downregulating genes associated with GPCR ligand binding and neurotransmitter transport. SynGO analysis further identified selective regulation of synapse-associated genes, predominantly affecting presynaptic and neurotransmitter uptake mechanisms. Together, these findings indicate that ketamine exerts rapid antidepressant-relevant effects in human neurons by enhancing excitatory synaptic organization and engaging downstream transcriptional programs linked to monoaminergic signaling. This hiPSC-based model provides a mechanistic framework for understanding ketamine’s rapid action and a foundation for future studies on differential responses in TRD patients.
Comparable studies
Other experimental studies on ketamine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Ketamine activates psychosis and alters limbic blood flow in schizophrenia Schizophrenic individuals | 1995 | Experimental study | |
| The spectral exponent of the resting EEG indexes the presence of consciousness during unresponsiveness induced by propofol, xenon, and ketamine Healthy participants | 2019 | Controlled experimental study | n = 15 |
| Ketamine Increases Human Motor Cortex Excitability to Transcranial Magnetic Stimulation Normal human subjects | 2003 | Experimental study | n = 7 |
| Evidence that Subanesthetic Doses of Ketamine Cause Sustained Disruptions of NMDA and AMPA-Mediated Frontoparietal Connectivity in Humans Human participants | 2015 | Experimental study | |
| S(+)-ketamine Effect on Experimental Pain and Cardiac Output Healthy adult volunteers (10 men and 10 women) | 2009 | Pharmacokinetic-pharmacodynamic modeling study in healthy volunteers | n = 20 |
Citations in the library
Cites 11
- mTOR-Dependent Synapse Formation Underlies the Rapid Antidepressant Effects of NMDA Antagonists Science August 19, 2010
- Mechanisms of Ketamine Action as an Antidepressant Molecular Psychiatry March 13, 2018
- Ketamine and Other NMDA Antagonists: Early Clinical Trials and Possible Mechanisms in Depression American Journal of Psychiatry October 1, 2015
- Ketamine: a paradigm shift for depression research and treatment Neuron March 1, 2019
- Double-Blind, Placebo-Controlled, Dose-Ranging Trial of Intravenous Ketamine as Adjunctive Therapy in Treatment-Resistant Depression (TRD) Molecular Psychiatry October 3, 2018
and 6 more in the library