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Background: Novel antidepressive substances are challenging the explanations for the mechanisms of action of traditional psychopharmacology., Objective: What could be the shared effects of various antidepressants and in this context what role do extrapharmacological factors, such as the body and environment, play?, Material and Method: The available literature on clinical and preclinical data for assumed combined active factors of serotonergic psychedelic drugs, (es)ketamine, monoaminergic antidepressants and zuranolone are presented and the influence of context factors on the individual mechanisms of action is discussed., Results: There are many indications that classical and novel pharmacological approaches could share similar mechanisms of action in the treatment of depression. These mechanisms favor long-term neuroplasticity, which can trigger subsequent molecular cascades and vice versa. Furthermore, an improvement in the negative bias in emotional processing could be detected for most antidepressive substances. The influence of extrapharmacological factors appears to be necessary so that the biopsychological alterations can have an antidepressive effect., Conclusion: Instead of attributing factors such as environment, body and social interaction to placebo effects, they should be tested as essential components of the antidepressive effect and considered in the clinical practice., Competing Interests: Einhaltung ethischer Richtlinien. Interessenkonflikt: G. Gründer war in den letzten drei Jahren als Berater für AbbVie (Chicago, USA), Boehringer Ingelheim (Ingelheim, Deutschland), das Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen (IQWiG, Köln, Deutschland), Johnson & Johnson (New Brunswick, USA), Lundbeck (Kopenhagen, Dänemark), MindMed (New York, USA), Otsuka (Chiyoda, Japan), Recordati (Mailand, Italien), Roche (Basel, Schweiz) und ROVI (Madrid, Spanien) tätig. Er war als Referent für Gedeon Richter (Budapest, Ungarn), Johnson & Johnson, Lundbeck, Otsuka und Recordati tätig. Er erhielt Forschungsunterstützung von Beckley Psytech (London, UK) und Boehringer Ingelheim. Er ist Mitgründer und/oder Gesellschafter der Mind and Brain Institute GmbH (Zornheim, Deutschland), der OVID Health Systems GmbH, der OVID Clinic Berlin GmbH, der OVID Beteiligungsgesellschaft mbH, der OVID Tagesklinik GmbH & Co. KG (alle Berlin, Deutschland) und der MIND Foundation gGmbH (Berlin, Deutschland). Er ist stellvertretender Vorsitzender der Deutschen Gesellschaft für Psychedelische Forschung und Therapie (DGPFT). M. Spangemacher, J. Reinwald, H. Adolphi, L. Kärtner, L.J. Mertens und C.N. Schmitz geben an, dass kein Interessenkonflikt besteht. Für diesen Beitrag wurden von den Autor/-innen keine Studien an Menschen oder Tieren durchgeführt. Für die aufgeführten Studien gelten die jeweils dort angegebenen ethischen Richtlinien., (© 2025. The Author(s).)

Background: Repetitive transcranial magnetic stimulation (rTMS) has recently gained relevance in treating different psychiatric disorders. Limited evidence suggests that the beneficial effects of rTMS on psychopathology could be at least partly mediated through changes in inflammatory response. This systematic review summarizes the literature on whether rTMS can modulate inflammatory markers and thus positively influence the course of psychiatric illnesses., Materials and Methods: A systematic review of rTMS and inflammatory markers in psychiatric diseases was conducted according to PRISMA guidelines. Information on the association between rTMS treatment response and changes of inflammatory markers was extracted. The quality of the studies was assessed using the National Heart, Lung, and Blood Institute for human studies and the Systematic Review Center for Laboratory Animal Experimentation for animal studies., Results: This review includes 17 studies (2 animal and 15 human studies) on the relationship between rTMS treatment response and changes of inflammatory markers. Positive changes in microglial activity and anti-inflammatory effects were associated with behavioral improvement in animal models of depression. However, these findings have not been consistently replicated in human studies focusing on treatment-resistant depression. While several studies reported rTMS-induced alterations in peripheral inflammatory markers, only two could demonstrate their association to clinical treatment response. Notably, most studies showed poor or moderate quality in the bias assessment., Conclusions: While certain human studies suggest an association between rTMS-induced anti-inflammatory effects and improvement in psychopathology, heterogeneity, and underpowered analyses constrain the generalizability of these results. The discrepancy between animal and human findings highlights the need for larger, standardized human studies., Trial Registration: (PROSPERO Registration: CRD42023492732)., (© 2024. The Author(s).)

Competing Interests: Conflicts of Interest: Xenia Marlene Hart, Elea Saalfrank, and Alexander Sartorius declared no conflicts of interest. Jonathan Reinwald received speaker fees from Egetis Therapeutics. Moritz Spangemacher received speaker fees from MIND Foundation GmbH. Gerhard Gründer has served as a consultant for Allergan, Boehringer Ingelheim, Institute for Quality and Efficiency in Health Care (IQWiG), Janssen-Cilag, Lundbeck, Otsuka, Recordati, ROVI, Sage, and Takeda. He has served on the speakers' bureau of Gedeon Richter, Janssen Cilag, Lundbeck, Otsuka, Recordati. He has received grant support from Boehringer Ingelheim, Lundbeck, and Saladax. He is a cofounder and/or a shareholder of Mind and Brain Institute GmbH, Brainfoods GmbH, OVID Health Systems GmbH, and MIND Foundation GmbH. The other authors report no conflicts of interest.

Background and Purpose: The benefit of endovascular thrombectomy (EVT) treatment is still unclear in stroke patients presenting with extensive baseline infarct. The use of additional imaging biomarkers could improve clinical outcome prediction and individualized EVT selection in this vulnerable cohort. We hypothesized that cerebral venous outflow (VO) may be associated with functional outcomes in patients with low Alberta Stroke Program Early CT Score (ASPECTS)., Methods: We conducted a retrospective multicenter cohort study of patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO). Extensive baseline infarct was defined by an ASPECTS of ≤5 on admission computed tomography (CT). VO profiles were assessed on admission CT angiography using the Cortical Vein Opacification Score (COVES). Favorable VO was defined as COVES ≥3. Multivariable logistic regression was used to determine the association between cerebral VO and good clinical outcomes (90-day modified Rankin Scale score of ≤3)., Results: A total of 98 patients met the inclusion criteria. Patients with extensive baseline infarct and favorable VO achieved significantly more often good clinical outcomes compared to patients with unfavorable VO (45.5% vs. 10.5%, P<0.001). Higher COVES were strongly associated with good clinical outcomes (odds ratio, 2.17; 95% confidence interval, 1.15 to 4.57; P=0.024), independent of ASPECTS, National Institutes of Health Stroke Scale, and success of EVT., Conclusions: Cerebral VO profiles are associated with good clinical outcomes in AIS-LVO patients with extensive baseline infarct. VO profiles could serve as a useful additional imaging biomarker for treatment selection and outcome prediction in low ASPECTS patients.

Introduction: A burst suppression pattern in the electroencephalogram represents a down-regulated brain state, which also occurs in the postictal phase of electroconvulsive therapy (ECT). Suppressive actions of the brain to terminate the seizure are thought to be necessary for the efficacy of ECT. On the other hand, recent studies showed an association of burst suppression in general anesthesia or sedation with (postprocedural) cognitive complications., Methods: We retrospectively examined the length of postictal burst suppression and reorientation time in 49 ECT sessions of 25 consecutive patients. Burst suppression duration was determined by bispectral index monitoring and defined as the time with a bispectral index value of less than 20%. The association between duration of burst suppression and reorientation time was analyzed with multivariate logistic and linear regression analysis controlling for several covariates., Results: The reorientation time showed a statistically significant association with the duration of burst suppression, but with no other variable. Longer phase of postictal burst suppression predicted longer reorientation time in the recovery room (P = 0.046)., Conclusions: The association between the duration of postictal burst suppression and reorientation time after ECT in this sample suggests that (not only the efficacy but also the) cognitive adverse effects of ECT might be related to the extent of postictal central inhibition after the termination of the seizure., Competing Interests: The authors have no conflicts of interest or financial disclosures to report., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Copy number variations (CNV) involving multiple genes are ideal models to study polygenic neuropsychiatric disorders. Since 22q11.2 deletion is regarded as the most important single genetic risk factor for developing schizophrenia, characterizing the effects of this CNV on neural networks offers a unique avenue towards delineating polygenic interactions conferring risk for the disorder. We used a Df(h22q11)/+ mouse model of human 22q11.2 deletion to dissect gene expression patterns that would spatially overlap with differential resting-state functional connectivity (FC) patterns in this model (N = 12 Df(h22q11)/+ mice, N = 10 littermate controls). To confirm the translational relevance of our findings, we analyzed tissue samples from schizophrenia patients and healthy controls using machine learning to explore whether identified genes were co-expressed in humans. Additionally, we employed the STRING protein-protein interaction database to identify potential interactions between genes spatially associated with hypo- or hyper-FC. We found significant associations between differential resting-state connectivity and spatial gene expression patterns for both hypo- and hyper-FC. Two genes, Comt and Trmt2a, were consistently over-expressed across all networks. An analysis of human datasets pointed to a disrupted co-expression of these two genes in the brain in schizophrenia patients, but not in healthy controls. Our findings suggest that COMT and TRMT2A form a core genetic component implicated in differential resting-state connectivity patterns in the 22q11.2 deletion. A disruption of their co-expression in schizophrenia patients points out a prospective cause for the aberrance of brain networks communication in 22q11.2 deletion syndrome on a molecular level., (Copyright © 2021. Published by Elsevier Inc.)

The pleiotropic function of thyroid hormones (TH) is mediated by an organ specific expression of thyroid hormone transporters, deiodinases and TH receptors. In a series of studies we used the model of an experimentally induced hyper- or hypothyroidism in human volunteers to delineate TH action on the brain. A battery of neuropsychological testing paradigms was employed and complemented by structural and functional multimodal neuroimaging. Experimentally induced mild thyrotoxicosis for 6 weeks was associated with changes in brain structure (determined with voxel-based morphometry), resting state functional connectivity, and task-related functional activation in a working memory paradigm. Partial withdrawal of TH replacement in patients without thyroid (subclinical hypothyroidism) likewise lead to changes on multiple functional and structural brain measures. Importantly, the series of studies reviewed here identified the cerebellum as one crucial site of action., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

As ketamine is increasingly used as an effective antidepressant with rapid action, sustaining its short-lived efficacy over a longer period of time using a schedule of repeated injections appears as an option. An open question is whether repeated and single administrations would affect convergent neurocircuits. We used a combination of one of the most robust animal models of depression with high-field neuroimaging to perform a whole-brain delineation of functional mechanisms underlying ketamine's effects. Rats from two genetic strains, depressive-like and resilient, received seven treatments of 10 mg/kg S-ketamine (N = 14 depressive-like, N = 11 resilient) or placebo (N = 12 depressive-like, N = 10 resilient) and underwent resting-state functional magnetic resonance imaging. Using graph theoretical models of brain networks, we compared effects of repeated ketamine with those of single administration from a separate dataset of our previous study. Compared to single treatment, repeated ketamine evoked strain-specific brain network randomization, resembling characteristics of the depressive-like strain and patients. Several affected regions belonged to the auditory, visual, and motor circuitry, hinting at possible cumulative side effects. Finally, when compared to saline, repeated ketamine affected only a few local topological properties and had no effects on global properties. In combination with the lack of clear differences compared to placebo, our findings point toward an inefficacy of ketamine's long-term administration on brain topology, making questionable the postulated effect of repeated administration and being consistent with the recently reported absence of repeated ketamine's antidepressant efficacy in several placebo-controlled studies.

Ketamine acts as a rapid clinical antidepressant at 25 min after injection with effects sustained for 7 days. As dissociative effects emerging acutely after injection are not entirely discernible from therapeutic action, we aimed to dissect the differences between short-term and long-term response to ketamine to elucidate potential imaging biomarkers of ketamine's antidepressant effect. We used a genetical model of depression, in which we bred depressed negative cognitive state (NC) and non-depressed positive cognitive state (PC) rat strains. Four parallel rat groups underwent stress-escape testing and a week later received either S-ketamine (12 NC, 13 PC) or saline (12 NC, 12 PC). We acquired resting-state functional magnetic resonance imaging time series before injection and at 30 min and 48 h after injection. Graph analysis was used to calculate brain network properties. We identified ketamine's distinct action over time in a qualitative manner. The rapid response entailed robust and strain-independent topological modifications in cognitive, sensory, emotion, and reward-related circuitry, including regions that exhibited correlation of connectivity metrics with depressive behavior, and which could explain ketamine's dissociative and antidepressant properties. At 48 h ketamine had mainly strain-specific action normalizing habenula, midline thalamus, and hippocampal connectivity measures in depressed rats. As these nodes mediate cognitive flexibility impaired in depression, action within this circuitry presumably reflects ketamine's procognitive effects induced only in depressed patients. This finding is especially valid, as our model represents cognitive aspects of depression. These empirically defined circuits explain ketamine's distinct action over time and might serve as translational imaging correlates of antidepressant response in preclinical testing.

Rationale: Evidence indicates that ketamine's rapid antidepressant efficacy likely results from its antagonism of NR2B-subunit-containing NMDA receptors (NMDAR). Since ketamine equally blocks NR2A- and NR2B-containing NMDAR, and has affinity to other receptors, NR2B-selective drugs might have improved therapeutic efficiency and side effect profile., Objectives: We aimed to compare the effects of (S)-ketamine and two different types of NR2B-selective antagonists on functional brain networks in rats, in order to find common circuits, where their effects intersect, and that might explain their antidepressant action., Methods: The experimental design comprised four parallel groups of rats (N = 37), each receiving (S)-Ketamine, CP-101,606, Ro 25-6981 or saline. After compound injection, we acquired resting-state functional magnetic resonance imaging time series. We used graph theoretical approach to calculate brain network properties., Results: Ketamine and CP-101,606 diminished the global clustering coefficient and small-worldness index. At the nodal level, all compounds induced increased connectivity of the regions mediating reward and cognitive aspects of emotional processing, such as ventromedial prefrontal cortex, septal nuclei, and nucleus accumbens. The dorsal hippocampus and regions involved in sensory processing and aversion, such as superior and inferior colliculi, exhibited an opposite effect., Conclusions: The effects common to ketamine and NR2B-selective compounds were localized to the same brain regions as those reported in depression, but in the opposite direction. The upregulation of the reward circuitry might partially underlie the antidepressant and anti-anhedonic effects of the antagonists and could potentially serve as a translational imaging phenotype for testing putative antidepressants, especially those targeting the NR2B receptor subtype.