Progress in Neuro-Psychopharmacology and Biological Psychiatry

Despite extensive epigenetic reprogramming, induced pluripotent stem cells (iPSC) from schizophrenia patients (SZ) retain several molecular and functional features of this disease. Transcriptomic and epigenomic analyses were performed in iPSC of SZ and healthy control subjects (HC). Transcriptional profiles were largely similar between SZ and HC iPSC, whereas pronounced differences emerged following neural differentiation, with SZ NSC exhibiting dysregulation of genes involved in neurodevelopment and synaptic function. ZNF5c0 was identified as a uniquely and consistently upregulated gene in SZ iPSC, robustly discriminating SZ from HC iPSC. Epigenomic profiling revealed increased chromatin accessibility and reduced DNA methylation at the ZNF5c0 promoter in SZ iPSC. ChIP-seq data suggested that ZNF560 can bind to promoters of genes implicated in synaptic signaling and neuronal development. Moreover, a subset of these genes was found to be differentially expressed in SZ neural stem cells. Together, our results identify ZNF5c0 as a reprogramming-resistant epigenetic marker of schizophrenia and suggest an altered KRAB-ZNF-mediated regulation in early neurodevelopmental pathways underlying this disorder.

Fetal alcohol spectrum disorders (FASD) are caused by prenatal alcohol exposure (PAE), which leads to developmental defects during embryogenesis. Angiogenesis is one facet of development that is heavily dysregulated during PAE and where such impairment is poorly understood. Here we found that expression levels of focal adhesion molecules Tensin 1 (Tns1) and Tensin 2 (Tns2) were significantly reduced by alcohol exposure in brain microvascular endothelial cells (BMVECs). We also found that miR-150-5p, which we previously found was increased by PAE, regulates the expression of Tns1 and Tns2. Dual-luciferase assays demonstrated direct binding of miR-150-5p to the 3UTRs of Tns1 and Tns2. Additionally, we utilized sprouting angiogenesis bead assays to evaluate endothelial cell sprouting in response to ethanol (EtOH) treatment and following Tns1 and/or Tns2 overexpression as well as miR-150-5p modulation. Tns1 and Tns2 rescued both EtOH- and miR-150-5p-mediated deficits in sprouting angiogenesis. Overall, we found that miR-150-5p negatively regulates Tns1 and Tns2 in BMVECs and that augmenting Tns1 and Tns2 expression may reverse the negative effects of EtOH, and subsequent miR-150-5p elevation, thus improving endothelial cell sprouting during cerebrovascular development.

The social anxiety disorder (SAD) is one of the most common mental health disorders, often developing in adolescence. It can severely impair educational achievement, career progression, and social functioning. Certain individuals within the Chinese Kunming dog (CKD) population display spontaneous, SAD-like behaviors towards strangers, offering a valuable model for genetic investigation. Using whole-genome sequencing data, we conducted a genome-wide association study on this SAD-like behavior in 100 CKDs, identifying several genes previously linked to human psychiatric disorders. Notably, SLC6A3 reached genome-wide significance, whereas CADPS2 exceeded only the suggestive threshold and is therefore considered a network-supported candidate locus. By integrating weighted gene co-expression network analysis with public RNA-seq data from the VTA of 38 mice (after quality control), we further showed that Slc6a3 and Cadps2 are part of a co-expression network module associated with the dopamine system. These findings suggest that this specific module may play a functional role in the stranger-directed anxiety-related behaviours in CKDs. Furthermore, we identified Nrip3 as a key candidate transcriptional coregulator in this specific module. Subsequent virus-mediated overexpression and behavioural experiments showed that Nrip3 regulates gene expression within this network and induces a spectrum of behavioural alterations in mice, including social avoidance, anhedonia, and increased locomotor activity. Collectively, this study highlights the involvement of dopamine system genes in canine social anxiety and suggests Nrip3 as an upstream regulator of Slc6a3 associated with anxiety. The identification of conserved anxiety-related signatures between humans and dogs further supports the dog as a valuable translational model for psychiatric research.

Background: Stimulant exposure can induce acute stereotyped behaviors and chronic alterations in brain connectivity and white matter integrity. However, the temporal sequence and molecular changes linking these cocaine-induced phenotypes remain unclear. Methods: We combined LabGym-based behavioral analysis, longitudinal brain imaging, and cross-species molecular analysis in 11 common marmosets (Callithrix jacchus; seven male, four female): four underwent behavioral and imaging studies, six provided molecular data, and one provided immunohistochemical data. Male Cryab knockout and wild-type mice underwent functional studies. Results: Acute cocaine (5 mg/kg, intraperitoneally) induced rapid, repetitive lateral head movements, defined as head shaking. After 1 and 10 months of repeated exposure, resting-state functional connectivity was altered in sensory, parietal, prefrontal, motor, and hippocampal regions. Changes were detected at 1 month, whereas diffusion tensor imaging showed reduced fractional anisotropy and axial diffusivity in the corpus callosum splenium at 10 months, with no significant genu changes. Cross-species transcriptomic and proteomic comparison identified DPYSL2 and DNM3 as shared axon-associated molecules. Western blotting showed reduced DPYSL2 in brain tissue from cocaine-treated marmosets. CRYAB localized to O4-positive callosal oligodendrocytes and increased following chronic cocaine exposure. Cryab knockout mice had reduced corpus callosum thickness, increased forced-swim immobility, and reduced open-field distance traveled, supporting a role for CRYAB in corpus callosum integrity and depression-related behavior. Conclusions: These findings show that acute cocaine-induced stereotyped head shaking precedes functional connectivity changes and later corpus callosum deficits. Reduced DPYSL2 may be associated with axonal dysfunction, whereas increased CRYAB may represent a response to cocaine-induced white matter stress.

Stress is a physiological, adaptive, and preliminary response of the organism to situations of threats and instability caused by environmental and psychological stressors. The chronicity and predictability of stressors are important variables in determining neurobehavioral outcomes. While unpredictable chronic stress (UCS) protocols typically induce depressive-like phenotypes in rodents, in zebrafish the effects of these protocols are assessed using anxiety-like outcomes. This study aimed to analyze the effects of an unpredictable UCS on depressive-type behavioral parameters and brain lipid peroxidation in zebrafish. A 14-day UCS protocol was used, with 10 different types of stressors administered twice daily in a random manner, using draws, for greater unpredictability. Animals underwent the Novel Tank Test (anxiety-like outcome) and the Social Preference Test (depressive-like outcome) 24 hours after the end of the UCS protocol. Biochemical data were collected using a thiobarbituric acid reactive substances (TBARS) assay to quantify malondialdehyde (MDA), an indicator of lipid peroxidation. The findings suggest that prolonged exposure to stressors causes damage to the organism, with increased anxiety and decreased social preference, highlighting zebrafish as an efficient model in the investigation of the neurobiological and neuropathological mechanisms of stress.

A single injection of a subanesthetic dose of ketamine, an NMDA receptor antagonist, induces schizophrenia-like behavior in mice. Previous studies investigated the effect of single injection of ketamine on behavior and c-Fos expression in mice dose-dependently. However, there has not been functional magnetic resonance imaging (fMRI) study to investigate the effect of ketamine in mice. Here, we used awake fMRI and investigated the dose-dependent effect of single injection of ketamine in awaked mice. The lower-dose (5 mg/kg) ketamine increased functional connectivity (FC) with the thalamus and the hypothalamic nuclei. Higher-dose (50 mg/kg) ketamine increased widespread FC with cerebral cortex as well as hippocampus and thalamic nuclei. Graph theory analysis reveals that several regions of hypothalamus and cerebral cortex are essential for the network change by ketamine injection. These results indicate that sub-anesthetic ketamine dose-dependently alters the brain and indues the abnormal behavior in mice.

Neurological and cardiovascular disorders frequently coexist, yet targeted dual-system interventions remain underinvestigated. Transcranial magnetic stimulation (TMS), including intermittent and continuous theta-burst stimulation (iTBS/cTBS), non-invasively modulates primary motor cortex (M1) excitability. Concurrently, ketone monoesters (KME) show neuroprotective potential and alter cardiovascular hemodynamics. In a randomized, double-blind, placebo-controlled crossover study, 44 healthy young adults were stratified to receive iTBS or cTBS (n = 22/group). Participants completed two sessions separated by 1 week, consuming either a KME or placebo beverage, followed by TBS 1-hour post-ingestion. Motor evoked potentials (MEPs) from the right first dorsal interosseous muscle were tracked for 30 minutes post-stimulation. Blood pressure was measured every 3-5 minutes, heart rate was monitored continuously, and venous blood was sampled for glucose, beta-hydroxybutyrate (BHB), pro-BDNF, mature BDNF (mBDNF), and the BDNF rs6265 polymorphism. We found that KME significantly elevated blood BHB and heart rate while decreasing blood glucose and diastolic blood pressure. KME did not alter resting motor threshold, baseline MEP amplitude, or MEP latency. Factorial analysis showed no significant modification of post-TBS MEP time courses by KME. In exploratory within-condition analyses, placebo-cTBS induced significant late increases in MEP amplitude, whereas KME-cTBS showed a blunted post-stimulation response. Serum mBDNF and pro-BDNF concentrations remained unchanged. In conclusion, combining KME and TBS is feasible, well-tolerated, and may exert concurrent neurological and cardiovascular effects. This work opens the door to a novel metabolic-neuromodulatory avenue that merits confirmation in larger cohorts and establishment of clinical relevance in patients with comorbid neurological and cardiovascular disorders.

Early-life psychosocial adversity increases vulnerability to stress-related disorders and may begin as early as prior to conception via maternal stress. Consequently, early-life stress (ELS) in offspring may accumulate across early development. The short-allele variant of the serotonin transporter (SERT) gene has been implicated in depression risk and higher anxiety sensitivity following stress exposure, but for cumulative ELS it is unknown whether behavioral effects depend on the SERT genotype. In this study, we used heterozygous SERT knockout (SERT+/-) rats to model reduced SERT expression similar to human short-allele carriers. To investigate the effects of cumulative ELS on offspring behavioral phenotype, dams were exposed to stress before, during and after pregnancy, combined with offspring postnatal maternal separation. Cognitive, affective, and social behaviors were assessed in wild-type (WT) and SERT+/- (HET) male and female adults. Maternal care and anhedonia-like behaviors in dams were also assessed. Dams exposed to the cumulative stress (STR) displayed increased arched-back licking and grooming compared to controls (CTR). In the offspring, HET rats showed increased social investigation and tended to display hyperactivity compared to WT. Anxiety-like behavior was higher in HET females compared to WT females, with no genotype differences in males. Independent of genotype, STR rats consumed less sucrose and showed impaired object recognition compared to CTR; however, HET-STR rats performed better in the object recognition than WT-STR rats. A significant SERT genotype x cumulative ELS x sex interaction revealed opposing, sex-dependent effects on anxiety-like behavior. HET-STR females showed more anxiety-like responses relative to HET-CTR and WT-STR females, as well as HET-STR males. In contrast, HET-STR males were less anxious than HET-CTR and WT-STR males. Reduced SERT expression is linked to more social investigation alongside increased anxiety, particularly in SERT+/- females. While cumulative ELS did not induce robust anxiety-like and depressive-like phenotypes, overall, it impaired memory performance, an effect partially mitigated in SERT+/- rats. Notably, the SERT genotype differentially modulated anxiety-like behavior in male versus female offspring, increasing vulnerability in SERT+/- females while reducing it in SERT+/- males, an effect further amplified by exposure to cumulative ELS. These results underscore sex as a critical determinant in the interaction between genetic susceptibility and cumulative exposure to early adversity in shaping affective outcomes.

We conducted an open-label pilot study of bilateral nucleus accumbens-anterior limb of the internal capsule (NAc-ALIC) deep brain stimulation (DBS) in three patients with treatment-resistant schizophrenia (TRS). Clinical symptoms, global functioning, cognition, stimulation parameters and intracranial local field potential (LFP) were assessed over 24 weeks. Two patients met the prespecified clinical response criterion, defined as a [≥]40% reduction in Positive and Negative Syndrome Scale (PANSS) total score, by week 8 and showed PANSS reductions of 69.0% and 69.4%, respectively, at week 24. The third patient showed a 18.7% reduction at week 24. Responders showed improvements in global functioning and selected cognitive domains. Longitudinal LFP recordings revealed increased gamma-band relative power and reduced theta-band activity in responders, whereas these changes were less consistent in the non-responder. DBS was generally well tolerated, with transient stimulation-related adverse effects resolving after reprogramming. These findings provide preliminary clinical evidence supporting further investigation of NAc-ALIC DBS in TRS and suggest that individualized programming and intracranial physiological measures may contribute to the identification of treatment-response signatures.

Background: Interoception refers to the processing, integration, interpretation, and regulation of bodily signals by the brain. It is crucial to motivational and affective functioning such as subjective experience of arousal (i.e., intensity of emotion). Previous studies found altered self- report of arousal in people with schizophrenia, but the underlying biological mechanism is unclear. This study aimed to investigate interoceptive processing and emotional experience in schizophrenia by triangulating self-report, cardiac dynamics, and heartbeat-evoked potential (HEP; an event-related potential that reflects cortical processing of heartbeats). Methods: A total of 39 participants with schizophrenia spectrum disorders (SZ; 36% female) and 31 healthy controls (HC; 35% female) reported subjective arousal level when viewing images of varying emotional intensity while electroencephalogram and electrocardiogram were being recorded. Results: We found that intense images led to larger heartrate decelerations and higher subjective arousal ratings in HC, but did not modulate heartrate changes in SZ and were less predictive of their subjective ratings. Subjective ratings were predictive of cardiac dynamics in HC, but not in SZ. SZ showed a less negative HEP amplitude than HC when viewing less intense images. Lastly, SZ with less severe positive and negative symptoms exhibited cardiac dynamics more similar to those of HC. Conclusions: These findings suggest both reduced cardiac reactivity to emotional stimuli and a disconnect between interoceptive afferent signals and cortical processing, leading to different subjective emotional experience in people with schizophrenia. Studying interoception using a multimodal approach may reveal important insights into the underlying mechanisms of altered emotional experience in schizophrenia.

Autism spectrum disorder (ASD) is a common neurodevelopmental disease with no currently effective treatments. In this study, Xenon (Xe), a noble gas used clinically as an anesthetic and a neuroprotectant, has been investigated for its potential therapeutic effects in ASD. Two genetic ASD mouse models (Mef2c mutant and Shank3-/- mice) were exposed to a low concentration of xenon (25%) mixed with oxygen (30%) and balanced with nitrogen for a single exposure of 30 min or for 10 min per day for 10 days. These Xe exposure paradigms rescued ASD-like behaviors in both male and female mice. The behavioral improvements persisted for up to 10 days following termination of the 10-day exposure paradigm. Mechanistically, Xe reduced glutamic acid decarboxylase expression in the inhibitory neurons (verified with RNAseq) of the paraventricular thalamic nucleus (PVT) and decreased GABA release during social interaction. Targeted infusion of the GABAA receptor agonist muscimol into the PVT abolished the Xe-mediated behavioral improvements. Reduced GABAergic transmission following Xe exposure increased PVT glutamatergic neuronal activity. Chemogenetic inhibition of these neurons eliminated the therapeutic effects of Xe, whereas chemogenetic activation mimicked the Xe-induced behavioral improvements. Furthermore, opto-inhibition of PVT glutamatergic projections to the central amygdala (CeA) blocked Xe-mediated behavioral improvement. Opto-activation of the PVT-CeA glutamatergic circuit reversed ASD-like behaviors. These findings demonstrate that Xe ameliorates ASD-like phenotypes in mouse models by modulating the PVT Glu-CeA circuit, supporting Xe as a novel potential therapy for ASD.

Background: Substance use disorders (SUDs) remain common worldwide and inadequately treated. Neuromodulation targets neural circuits involved in reward, craving, and cognitive control. However, the primary research literature has not been systematically mapped regarding the relative contributions of clinical and preclinical studies. Methods: We conducted a multi-database bibliometric analysis of primary studies on neuromodulation for SUD. Web of Science, Scopus, and PubMed were searched covering 2000-2025. After scope classification and exclusion of secondary literature, 810 primary research documents remained. Performance analysis and science mapping were performed with bibliometrix and VOSviewer. Results: Scientific output grew at a compound annual growth rate of 14.16% (2001-2025), accelerating after 2015. Of 810 studies, 82.8% were clinical, 12.5% preclinical, and 4.7% mixed/translational. Alcohol (31.5%) and nicotine/tobacco (25.7%) dominated the literature and were overwhelmingly clinical (>92%), whereas cocaine and opioids retained larger preclinical shares (24-27%). Repetitive transcranial magnetic stimulation (rTMS) was the leading modality (31.6%), followed by deep brain stimulation (24.9%) and transcranial direct current stimulation (24.2%). Keyword co-occurrence revealed three clusters: a clinical neuromodulation core, a nicotine/tobacco axis, and a preclinical reward-circuitry module. The United States and China led in output. Conclusions: Neuromodulation research for SUD is expanding rapidly and is heavily skewed toward clinical investigations. A persistent clinical-preclinical asymmetry and limited explicitly translational work constitute structural features of the field. Greater integration between mechanistic and clinical research is needed to advance definitive trials.

Background: Nicotine dependence is a major contributor to early mortality in individuals with schizophrenia, yet effective treatments remain limited. Drug cue-reactivity is a key contributor to nicotine use. Although transcranial magnetic stimulation (TMS) can reduce nicotine use and cue-reactivity, conventional left dorsolateral parietal (DLPFC)-targeted TMS is less effective in those with schizophrenia, highlighting the need for alternative, circuit-based targets. Because default node network (DMN) function is implicated in schizophrenia, cue-reactivity, and nicotine use, we investigated whether DMN-targeted TMS modulates cue-elicited brain activity in nicotine-using individuals with schizophrenia. Study Design: 63 nicotine-using individuals (schizophrenia: n=31, non-psychosis control: n=32) participated in a randomized, crossover study comparing DMN-targeted and DLPFC-targeted TMS with pre/post-TMS neuroimaging and craving assessment. A nicotine cue-reactivity task was used concurrently with neuroimaging. Mixed-effect models were used to determine effects of TMS target and diagnosis, and model relationship between baseline craving and cue-reactivity change. Study Results: At baseline, we found a Cue Reactive Network composed of regions overlapping with the DMN, including clusters in the posterior cingulate cortex, medial prefrontal cortex, and bilateral lateral occipital cortex (voxel-wise p<0.005, cluster p<0.05). Baseline cue-reactivity in schizophrenia did not differ from controls. DMN-targeted TMS decreased cue-reactivity in schizophrenia across Cue Reactive Network (estimate=-0.180, p=0.009). DLPFC-targeted TMS did not impact cue-reactivity. We did not observe an effect of either TMS target in controls. Higher baseline unprovoked craving predicted larger decrease in cue-reactivity across the Cue Reactive Network (estimate=-0.034, p=0.004). Conclusion: DMN-targeted TMS is a promising intervention that modulates nicotine cue-elicited brain activity in schizophrenia.

MK-801, a phencyclidine (PCP) derivative also known as dizocilpine, is a potent noncompetitive antagonist of the N-Methyl-D-aspartate receptor (NMDAr). The NMDAr plays a critical role in mediating excitatory synaptic transmission in the central nervous system (CNS) and is important in regulating synaptic plasticity, learning, and memory. MK-801 is known to induce schizophrenia-like phenotypes in animal models by blocking the NMDAr. Several studies have reported that the cognitive impairment associated with schizophrenia is linked to functional defects of ion channels in parvalbumin-positive GABAergic interneurons. Kv3.1 is a voltage-gated K+ (Kv) channel involved in the rapid repolarization of the action potential in neurons; it is richly expressed in parvalbumin-positive GABAergic interneurons and is associated with fast, repetitive spike generation. A decrease of Kv3.1 in the CNS has been reported to be associated with schizophrenia. In the present study, the effect of MK-801 on Kv3.1 was investigated using the whole-cell patch-clamp technique in Chinese hamster ovary (CHO) cells stably expressing Kv3.1. MK-801 caused a concentration-dependent inhibition of Kv3.1, with an IC50 of 10.81 M and a Hill coefficient of 0.89. The blocking potency was stronger at depolarized potentials, indicating a voltage-dependent block. MK-801 also produced a use-dependent block, inducing progressive inhibition with repeated stimulation at increased frequencies (1 Hz and 2 Hz), consistent with a delay in recovery from inactivation of Kv3.1 in the presence of MK-801. In addition, MK-801 induced a hyperpolarizing shift in the voltage dependence of the steady-state inactivation curve of Kv3.1. Taken together, these results indicate that MK-801 blocks Kv3.1 expressed in CHO cells in a concentration-, voltage-, and state-dependent manner. Given the importance of Kv3.1 in parvalbumin-positive, fast-spiking GABAergic interneurons, these findings suggest that MK-801 may alter the firing patterns of these inhibitory neurons, contributing to the onset and symptoms of schizophrenia.

Animals experience stressors in a variety of contexts that result in activation of neuroendocrine and cellular stress responses. Release of stress hormones can disrupt or restore redox homeostasis, and the resulting changes in oxidative states, physiology and behavior vary by an individuals stress coping style. However, oxidative stress can also directly modulate neuroendocrine stress signaling. To what extent individual differences in brain antioxidant levels alter behavioral stress levels is not well understood. The present study investigated how N-acetylcysteine amide (NACA), an antioxidant and glutamate-modulating compound, regulates stress behavior across zebrafish (Danio rerio) with different stress coping styles (proactive, reactive). Following 24-hour exposure to NACA or control conditions, we quantified individual and composite stress behaviors using a Light-Dark Test (LDT). As expected, both proactive fish and NACA-treated fish showed significantly lower stress behaviors compared to reactive and control animals, respectively. Notably, stress-reducing effects of NACA were only seen in those with a reactive stress coping style. Overall, our data suggest that antioxidant mechanisms (e.g., glutathione system) may be key in facilitating the distinct behavioral and physiological responses to stressors that characterize alternative stress coping styles. The results underscore how individual differences in stress coping style and redox state can influence behavioral responses to stress.

RationalePsychedelic compounds such as psilocybin have attracted growing interest for their potential therapeutic effects in psychiatric disorders, with improvements in cognitive flexibility proposed as a possible mechanism of action. However, the effects of psychedelics on cognitive flexibility remain poorly understood. ObjectiveThis study aimed to examine the acute and post-acute effects of psilocybin (0.1, 0.3, 1 mg/kg) and lysergic acid diethylamide (LSD, (0.02, 0.04, 0.08 mg/kg) on cognitive flexibility in male rats. MethodsThis was tested using two variants of the probabilistic reversal learning task (PRLT): a touchscreen-based operant task and a more ethological foraging-based task. ResultsIn the touchscreen PRLT, acute psilocybin disrupted task engagement, with animals completing fewer trials and showing increased trial initiation latency, although psilocybin also showed a trend toward faster initial rule acquisition. However, psilocybin did not significantly alter the number of rule changes achieved, a canonical measure of cognitive flexibility, or feedback sensitivity. LSD similarly produced limited acute effects, although the highest dose reduced lose-shift probability, suggesting decreased sensitivity to negative feedback under some conditions. Post-acute effects of psilocybin were minimal in both PRLT variants and, where LSD effects were observed these occurred across different doses and timepoints without a consistent pattern. ConclusionsOverall, these findings suggest that serotonergic psychedelics do not robustly enhance reversal learning in these paradigms and that apparent learning effects may reflect transient disruptions in task engagement rather than improvements in cognitive flexibility. These results also highlight potential limitations of these PRLT paradigms for detecting psychedelic-induced changes in cognitive flexibility in rodents.

Stressful experiences are a major risk factor for the development of neuropsychiatric disorders in vulnerable individuals. Identifying features that can distinguish stress-susceptible from resilient individuals remains a central goal in stress neurobiology. Due to the routine exclusion of female subjects from stress research or the use of male-defined criteria in behavioral characterization of subjects post-stress, female stress responses and vulnerability profiles remain poorly understood. This work aimed to gain a better understanding of sex-specific stress responses to social defeat stress. Here, we used a novel paired male-female social defeat paradigm and tracked subjects longitudinally in a ''two-hit'' design to evaluate responses to both acute social defeat stress (ASDS) and chronic social defeat stress (CSDS), and to determine how prior stress exposure influences subsequent vulnerability. We found that both ASDS and CSDS induces changes in social avoidance/approach behavior in males but not females, as measured by a classic social interaction ratio. Prior ASDS exposure enhanced susceptibility to subsequent CSDS most clearly in males, with females displaying specific changes in corner zone occupancy. Furthermore, we observed divergent anxiety profiles between males and females in a post-stress behavioral battery. Finally, females exhibited specific stress-related locomotor responses following ASDS. Together, these findings suggest that females may adopt distinct behavioral strategies following social defeat stress.

Schizophrenia spectrum disorders (SSD) have been linked to immune dysregulation and altered intestinal barrier function, although findings across studies remain inconsistent. The present study investigated circulating markers of intestinal permeability and immune activation in individuals with early-stage SSD and healthy controls and examined their associations with clinical outcomes. Serum concentrations of intestinal fatty acid-binding protein (iFABP), zonulin, soluble CD14 (sCD14), bactericidal/permeability-increasing protein (BPI), and lipopolysaccharide-binding protein (LBP) were measured in 36 patients with SSD at baseline and one-year follow-up and in 36 matched healthy controls. Linear mixed-effects models adjusted for age, sex, and body mass index (BMI) were used to evaluate group differences and longitudinal changes. No biomarker differences between patients and controls, and no longitudinal changes within patients, remained statistically significant after correction for multiple testing. Similarly, biomarker concentrations were not associated with symptom severity, global functioning, or neutrophil-to-lymphocyte ratio (NLR). Exploratory analyses identified a robust positive association between BMI and zonulin concentrations and additional associations among iFABP, LBP, and sCD14. Exploratory mixed-effects models identified a negative non-significant association between iFABP and sCD14 after adjustment for age, sex, and BMI. Overall, the findings do not support a generalized alteration of gut permeability or immune activation markers in SSD. Instead, they suggest that variation in gut-related biomarkers may be more strongly influenced by metabolic and individual factors than by diagnosis or current symptom severity.

Background. Serotonergic psychedelics show promise for treating psychiatric disorders, with symptom improvements lasting for weeks after a single dose. Clarifying the neural basis of these effects would benefit from an identification of empirical biomarkers of such lasting shifts in brain function. Resting state EEG offers a rapid (<5 minute), low-cost window into functional brain networks. However, connectivity is not static, but cycles between recurring semi-stable patterns that vary across frequency bands. Here we employed a dynamic function connectivity (dFC) framework to identify frequency-specific connectivity states and examine how they change in the weeks following psychedelic use. Methods. We collected resting-state EEG from individuals who had used one of two serotonergic psychedelic subclasses within the prior three weeks, psilocybin/LSD (typical; n=14) or 5-MeO-DMT (atypical; n=12), and age- and sex-matched controls (n=16). Frequency-band-specific spatial connectivity states (phase-lag index) were estimated across the full sample (5 per band). Groups were compared on proportion and dwell-time (per state) and state-to-state transitions. Results. A right frontoparietally-distributed beta synchrony state was dominant after both typical and atypical psychedelics use (proportion/dwell-time). This effect correlated with the number of days since using psychedelics. A globally-distributed theta-band state was prominent in recent users of typical psychedelics but occurred less often in atypical users. In contrast, neural entropy (Lempel-Ziv complexity; known to increase acutely during psychedelic dosing) was not altered in recent users of either subclass. Conclusion. These results reveal a beta-band signature of altered neural dynamics in the week following a psychedelic dose, consistent with a relaxation of brain network hierarchy after psychedelics.

Background: Stimulant and non-stimulant medications increase fronto-striato-thalamic activation in youth with Attention-Deficit/Hyperactivity Disorder (ADHD). However, comparative effects of the more recently licensed stimulant lisdexamfetamine and non-stimulant guanfacine on functional magnetic resonance imaging (fMRI) correlates in ADHD are unknown. Methods: This exploratory randomised, placebo-controlled, double-blind, crossover study compared fMRI activation in youth with ADHD during a tracking stop-signal task (SST; N = 12), a working memory task (N-back; N = 11) and a sustained attention task (SAT; N = 10), after single clinical doses of either guanfacine extended-release, lisdexamfetamine, or placebo, with one-week washouts. Twenty-one demographically matched typically developing controls (TD) were assessed once to test for potential normalisation of case-control activation differences. Results: Region of interest analysis showed increased right caudate and putamen activation for lisdexamfetamine versus placebo during N-back and SAT, respectively. Both drugs shared an increase in left superior temporal activation versus placebo during N-back. In whole-brain analyses only lisdexamfetamine increased precuneus/posterior cingulate activation during SST versus guanfacine, and during N-back in pre- and postcentral and occipital cortices versus placebo. During SST, placebo-treated ADHD versus TD showed reduced putamen, insula, parietal and occipital activation that was potentially attenuated/normalised under lisdexamfetamine, while under guanfacine lingual gyrus underactivation remained, with additional precuneus and middle temporal underactivation. Also, only lisdexamfetamine improved and normalised SST performance. Conclusion: Lisdexamfetamine appears to have stronger and drug-exclusive upregulation and potential attenuation/normalisation effects than guanfacine on basal ganglia, posterior parieto-occipital and sensorimotor activations during ADHD-relevant executive function tasks with some shared putamen and superior temporal effects.