Each month our editorial team sifts through hundreds of papers and curates notable findings—for practitioners and informed readers who want to stay current with the evidence. Subscribe to the monthly Research Digest for expert analysis and concise summaries of key papers.
This umbrella review looked at the best existing reviews and large studies to see if depression is linked to low serotonin or low serotonin activity. Across measures of serotonin in fluids, receptor and transporter studies, tryptophan depletion experiments, and large genetic studies, the evidence was mixed or absent. The authors…
This study in rodents and in neuronal cell cultures found that ketamine and its antidepressant metabolite (2R,6R)-HNK rapidly lower neuronally released glutamate in brain regions linked to depression. Using fast glutamate sensors (FAST), isolated synapses, and primary cortical neurons, the authors showed reduced depolarization-evoked glutamate release within 30 minutes after…
The researchers used PET scans with [11C]UCB-J to measure SV2A, a protein that marks presynaptic nerve terminals, and tested whether a single ketamine dose changes synaptic density in the living brain. Overall, they did not find a measurable change in SV2A 24 hours after one ketamine dose in non-human primates,…
Researchers pooled results from 29 human studies that measured blood levels of a protein called brain-derived neurotrophic factor, or BDNF, after people received so-called psychoplastogen drugs such as ketamine or psychedelics. They found no clear change in blood BDNF after these drugs. The authors say this does not prove the…
