Journal of Psychopharmacology最新文献

Background: Research on caffeine and cognitive performance remains controversial. Variations in genes associated with caffeine metabolism and response such as CYP1A2, AHR and ADORA2A may account for variable findings.

Aim: To investigate caffeine × gene interactions on cognitive performance in all key domains of cognition in healthy individuals.

Methods: Participants completed a lifestyle and food frequency questionnaire and a cognitive test battery including validated tasks to assess the domains of social cognition, memory, attention and executive function. Genotyping was performed for AHR rs6968554, CYP1A2 rs2472297, ADORA2A rs5751876, ADA rs73598374 and APOE rs429358 and rs7412.

Results: Significant gene × caffeine interactions were observed for the domains of social cognition, (F_{2, 123} = 5.848, p = 0.004) and executive function (F_{2, 109} = 3.690, p = 0.028). 'Slow' metabolisers had a higher performance in social cognition compared with 'fast' metabolisers among high-caffeine consumers (p = 0.004), while 'fast' metabolisers had a higher performance in executive function compared with 'slow' metabolisers among moderate caffeine consumers (p = 0.002).

Conclusions: The present findings suggest an association between genetic caffeine metabolism, habitual caffeine intake and cognitive function in the domains of social cognition and executive function. More research in naturalistic environments using larger cohorts is needed to confirm these findings to add to our understanding of how habitual caffeine may influence cognitive function based on individual genotype.

Background: Daridorexant is a dual orexin receptor antagonist approved for the treatment of chronic insomnia disorder.

Aims: Investigate the auditory awakening threshold (AAT), postural stability, and cognitive function during the night following evening administration of daridorexant 25 and 50 mg.

Methods: Double-blind, placebo-controlled, randomized, 3-way (placebo, 25, 50 mg) crossover study in 36 healthy male and female nonelderly adult and elderly subjects (1:1 sex/age ratio). Four hours after bedtime administration, the AAT was determined, followed by investigation of the main pharmacodynamic endpoint nocturnal postural stability (body sway) as well as functional mobility using the Timed Up and Go (TUG) test, and cognitive function/memory using the Visual Verbal Learning Test (VVLT).

Results: All 36 subjects completed the study. The average AAT was approximately 60 dB across treatments, i.e., there were no differences between daridorexant and placebo. Daridorexant marginally increased body sway by approximately 22%, while it had no clinically meaningful effect on the time to complete the TUG test (⩽1 s increase), and the VVLT (immediate and delayed number of correctly recalled words) showed minimal and clinically not meaningful differences of up to one word, all compared to placebo. Delayed word recognition was not different from placebo. The increase in body sway in the overall population was driven by nonelderly adults, as effects in elderly subjects were similar to placebo.

Conclusions: Following bedtime administration, daridorexant maintained the ability to awaken to an external noise stimulus in the middle of the night, allowing subjects to function safely.

Clinicaltrials.gov identifier: NCT05702177.

Introduction: Eating disorders are characterized by maladaptive eating behaviors and preoccupations around body shape, weight, and eating. The serotonin system has been among the most widely studied neurobiological factors in relation to eating disorders. Recent research also highlighted the role of oxytocin.

Aims and methods: This article aims to review animal and human studies on the involvement of central serotonin and oxytocin, and their interplay in eating disorders in particular. We synthesize results from studies using animal models of eating disorders and from research conducted in healthy individuals and clinical populations.

Results/outcomes: Altered serotonin neurotransmission and oxytocin levels in the brain-particularly in the hypothalamus, brainstem, and limbic regions-were associated with disturbances in eating behaviors and related maladaptive cognitions and emotions. These brain regions were found to constitute a typical neural network through which both central serotonin and oxytocin might operate in a bidirectional manner.

Conclusions/interpretation: Based on the preceding findings, we describe a developmental biopsychosocial model relevant to eating disorders, including the role of serotonin-oxytocin interactions in the brain. While it is clear that eating disorders are multifactorial in which many biopsychosocial pathways are involved, the current review highlights the importance of well-designed translational research when studying mechanisms of serotonin-oxytocin interactions in the brain. Such research would help to better understand the effects of joint central oxytocin and serotonin administration as a possible preventive or therapeutic intervention for eating disorders.

Background: Antidiabetic medications have shown efficacy in alleviating autism symptoms. However, there is a lack of clinical research on the impact of metformin on irritability associated with autism. This study aimed to assess the efficacy and safety of metformin as an adjuvant therapy with risperidone for managing irritability in children diagnosed with Autism Spectrum Disorder (ASD).

Methods: This is a randomized, 10-week, double-blind, placebo-controlled trial conducted at the children's autism clinic of Roozbeh Hospital (Tehran, Iran) from March 2024 to May 2024. Participants were divided into two groups of risperidone plus metformin (500 mg per day) and risperidone plus placebo and were assessed at baseline, weeks 5 and 10 with the aberrant behavior checklist-community scale (ABC-C).

Results: A total of 55 patients were included in the final analysis. Irritability (primary outcome measure) sharply decreased in the metformin compared to the placebo group (p = 0.008). Among the other four subscales of ABC-C, the hyperactivity/noncompliance score showed a significant drop during the baseline-to-week-5 period (p = 0.021). In addition, inappropriate speech subscales decreased significantly from baseline-to-week 5 in the metformin compared to the placebo group (p = 0.045). No other significant finding was observed among ABC-C scores for lethargy/social withdrawal or stereotypic behavior subscales.

Conclusion: Metformin demonstrated promising results in reducing irritability in ASD patients, which is in concordance with previous studies. However, further studies are required before any broad clinical recommendation.

Importance: Individuals with autism spectrum disorder (ASD) and intellectual disability often experience persistent challenges related to aggressive behaviour and agitation, highlighting the critical need for evidence-based pharmacological interventions among other strategies. Despite previous network meta-analyses (NMAs), the rapidly evolving landscape of treatment options necessitates ongoing and updated assessments.

Objective: To evaluate the efficacy and tolerability of various pharmacotherapies in managing agitation in children and adults with ASD or intellectual disabilities (ID).

Methods: Employing a systematic review and network meta-analysis methodology, we conducted an exhaustive search across multiple databases for double-blind, randomized controlled trials focusing on pharmacotherapies targeting agitation in these neurodevelopmental disorders. Adhering to Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, our assessment of study quality utilized the Cochrane Risk of Bias Tool to ensure methodological rigour and accuracy in data synthesis. Primary outcomes encompassed measures of reduced agitation, as indicated by treatment response on standardized agitation scales, alongside dropout rates, providing a comprehensive overview of treatment efficacy and tolerability.

Results: Our analysis included data from 38 eligible trials, involving 2503 participants across both pediatric and adult populations. Key pharmacological interventions, such as arbaclofen, risperidone plus buspirone, omega-3 fatty acids, risperidone plus palmitoylethanolamide, aripiprazole and risperidone, demonstrated significant efficacy in reducing agitation compared to placebo. Importantly, these treatments were generally well-tolerated, with no significant increase in all-cause dropouts compared to placebo, highlighting their suitability for clinical use in managing agitation in individuals with ASD or ID.

Conclusions: This study underscores the efficacy and tolerability of several pharmacotherapies in managing agitation among children and adults with ASD or ID. Our findings provide robust evidence that specific treatments, such as arbaclofen, risperidone plus buspirone and omega-3 fatty acids, are both effective and well-tolerated, offering valuable therapeutic options for clinicians. The study emphasizes the need for ongoing research to ensure that treatment strategies remain aligned with the evolving clinical landscape, ultimately improving patient outcomes in this challenging population.

Background: Delirium is a severe neuropsychiatric disorder associated with increased morbidity and mortality. Numerous precipitating factors and etiologies merge into the pathophysiology of this condition which can be marked by agitation and psychosis. Judicious use of antipsychotic medications such as intravenous haloperidol reduces these symptoms and distress in critically ill individuals.

Aims: This study aimed to develop a physiologically-based pharmacokinetic (PBPK) model for the antipsychotic medication haloperidol; estimate plasma and unbound interstitial brain concentrations for repetitive haloperidol administrations used in hyperactive delirium treatment; determine dopamine receptor occupancy and antagonism under these conditions; and correlate these results with Richmond Agitation-Sedation Scale (RASS) scores and the risk of developing extrapyramidal symptoms (EPSs).

Methods: The PBPK model for single and repetitive administrations of peroral and intravenous haloperidol was developed with PK-Sim software. The pharmacodynamic (PD) model for RASS scores with haloperidol unbound interstitial brain concentration passed as the regressor was developed with the MonolixSuite 2021R platform.

Results: Peak haloperidol plasma and unbound interstitial brain concentrations following a single 2 mg intravenous dose are 32 ± 5 nM and 2.4 ± 0.4 nM. With repetitive administrations, dopamine receptor occupancy is 70%-83% and D2_LR antagonism is 1%-10%. Variations in dopamine receptor occupancy correlate with changes in RASS scores in individuals with hyperactive delirium. There is a linear association between the odds ratio of developing EPS and peak D2_LR antagonism as functions of dopamine receptor occupancy.

Conclusions: Haloperidol dopamine receptor occupancy time course and D2_LR antagonism parallel RASS score changes and EPS risk, respectively.

Background and aim: Severe eating disorders, such as obesity, bulimia, and anorexia, keep increasing to epidemic proportions worldwide. Understanding of neuropeptides' role in complex hunger/satiety mechanisms may allow new prospects for treatment and prevention. Pyroglutamylated arginine-phenylalanine-amide peptides (QRFPs) are thought to enhance feeding following the central administration.

Methods: In our study, QRFP-26 was delivered into the lateral hypothalamic area of male Wistar rats by direct microinjections, as QRFP-26 expressing neurons and binding sights are densely present in this neural structure. The consumption of liquid food was measured over 60-min.

Results: Both doses (100 and 200 ng) significantly decreased food intake compared to the control treatment. Neuropeptide Y Y1R/NPFF (neuropeptide FF) antagonist BIBP3226 eliminated the anorexigenic effect caused by QRFP-26 administration. QRFP-26 affects neither general locomotion, behavioral patterns examined in the Open Field Test, nor anxiety.

Conclusion: This study is the first to report the anorexigenic action of QRFP-26 following direct administration into the hypothalamus, emphasizing steady locomotion and anxiety levels. We have shown that the effect of QRFP can be linked to the neuropeptide Y (NPY) Y1 or NPFF receptors.

Intranasal administration of oxytocin is emerging as a potential pharmacological option for mitigating social difficulties and regulating stress in autism spectrum disorder. However, initial single-dose and multiple-dose trials showed mixed results, with some demonstrating improvements in social and repetitive behavior and others showing no benefit over placebo. This perspective aims to elucidate factors contributing to this variability and to highlight pitfalls and opportunities in the field. We identified two major factors: design-related elements and individual participant characteristics. Pertaining to design-related elements, optimal dosing regimens have yet to be established, but appear to favor moderate intervention durations (i.e., 4-6 weeks) with intermittent and intermediate dosing (i.e., 24-32 IU every other day). Also, the context of the intervention seems crucial, as enhanced outcomes are mainly observed when oxytocin administration is paired with a socially stimulating and supporting environment. In addition, more adequate outcome measures have to be established to effectively assess oxytocin's impact, including behavioral scales and objective biophysiological markers tapping into stress and neurophysiological regulation. Future research should also account for individual participant differences in biological sex, developmental stage and cognitive and adaptive functioning, and incorporate (epi)genetic screening to identify responders. Overall, refining study designs and personalizing intervention protocols are essential for optimizing oxytocin's prosocial and anxiolytic effect in autism.

Background: More than 1 million people in the United States meet the criteria for cocaine use disorder (CUD), and over 19,000 people died from cocaine-related overdoses in 2020, but there are currently no FDA-approved medications for the treatment of CUD. Bupropion is an antidepressant currently prescribed to treat depression and nicotine addiction that acts by inhibiting norepinephrine and dopamine transporters.

Methods: In this study, we tested the effect of several doses of systemic bupropion on cocaine self-administration in male and female Wistar rats. In our first experiment, rats self-administered cocaine solution intravenously and were pretreated with systemic bupropion before self-administration sessions. In our second experiment, rats were pre-treated with bupropion before completing tests of locomotor activity and anxiety-like behavior.

Results: We found that high doses of systemically administered bupropion (60 mg/kg) attenuated cocaine self-administration in male and female rats during extended-access (6 h) sessions. We also found that the highest dose (60 mg/kg) of systemic bupropion was more efficacious in females relative to males during the first hour of operant sessions. Systemic bupropion did not alter locomotor activity, inactive lever presses, or food intake. The Estrous cycle did not influence cocaine intake with or without bupropion.

Conclusion: Our finding that bupropion attenuates cocaine self-administration suggests that bupropion may have promise for reducing cocaine use in humans.

Background: The metabotropic glutamate type 5 (mGlu5) receptor has emerged as a potential target for the treatment of psychosis that is suggested to have greater efficacy than antipsychotic medications that are currently utilized.

Aims: This study sought to elucidate mechanisms of therapeutic action associated with the modulation of the mGlu5 receptor in a disordered system marked by dopamine dysfunction. We further explored epigenetic mechanisms contributing to heritable transmission of a psychosis-like phenotype in a novel heritable model of drug abuse vulnerability in psychosis.

Methods: F1 generation male and female Sprague-Dawley rats that were the offspring of two neonatal quinpirole-treated (QQ) or two saline-treated (SS) animals were tested on nicotine-conditioned place preference (CPP). Regulators of G protein signaling 9 (RGS9) and β-arrestin 2 (βA2), which mediate dopamine (DA) D₂ signaling, were measured in the nucleus accumbens shell, prelimbic and infralimbic cortices. Reduced Representation Bisulfite Sequencing (RRBS) was used to analyze the cytosine methylation in these brain regions.

Results: Pretreatment with the mGlu5-positive allosteric modulator 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl)benzamide (CDPPB) 20 min prior to conditioning trials blocked enhanced nicotine CPP and mitigated aberrant G protein-dependent and -independent signaling in QQ animals. RRBS analysis revealed region-specific changes in several pathways, including nicotine addiction, dopamine synapses, and neural connectivity.

Conclusions: These results reveal an important region-specific mechanism of action for CDPPB in a system marked by enhanced DAD₂ receptor signaling. Results additionally reveal DNA methylation as an epigenetic mechanism of heritability, further validating the current model as a useful tool for the study of psychosis and comorbid nicotine use.