Efficacy and Safety of Selective Serotonin Reuptake Inhibitors, Serotonin-Norepinephrine Reuptake Inhibitors, and Placebo for Common Psychiatric Disorders Among Children and Adolescents: A Systematic Review and Meta-analysis

Expert recommendations for Germany's integration of psychedelic-assisted therapy

As clinical trials for psychedelics move into phase III in the USA, Europe must address its lag in integrating professional education around psychedelic-assisted therapy (PAT) and supporting psychedelic drug research. This paper evaluates the necessary frameworks for implementing PAT in Germany, emphasizing the nation's potential leadership role within the European Union. With Australia having already approved MDMA and psilocybin for mental health indications, the Ukrainian government exploring MDMA treatment for war-related PTSD, and initial clinical trials involving MDMA and LSD with patients in Switzerland which restarted the restricted medical use of these substances around 2014, the medical authorization of psychedelics in these countries establishes precedent showcasing both the promise and challenges of researching and implementing PAT in nations where the substances were formally scheduled as illicit substances. Key challenges include establishing rigorous standards for practitioner training, accessibility, and defining regulatory oversight. This paper focuses on the development of robust infrastructure in Germany, which will support the roll out of PAT, and details ethical considerations, training protocols, and governmental roles in the formulation of treatment frameworks. This approach aims not only to guide Germany in adopting PAT but also to influence broader European policy, ensuring that patients receive ethically sound and proficient care. The findings suggest pathways for Europe to reclaim its historical lead in psychiatric and therapeutic innovation.

Abnormalities in static and dynamic intrinsic neural activity and neurotransmitters in first-episode OCD

BACKGROUND

Obsessive-compulsive disorder (OCD) is a disabling disorder in which the temporal variability of regional brain connectivity is not well understood. The aim of this study was to investigate alterations in static and dynamic intrinsic neural activity (INA) in first-episode OCD and whether these changes have the potential to reflect neurotransmitters.

METHODS

A total of 95 first-episode OCD patients and 106 matched healthy controls (HCs) were included in this study. Based on resting-state functional magnetic resonance imaging (rs-fMRI), the static and dynamic local connectivity coherence (calculated by static and dynamic regional homogeneity, sReHo and dReHo) were compared between the two groups. Furthermore, correlations between abnormal INA and PET- and SPECT-derived maps were performed to examine specific neurotransmitter system changes underlying INA abnormalities in OCD.

RESULTS

Compared with HCs, OCD showed decreased sReHo and dReHo values in left superior, middle temporal gyrus (STG/MTG), left Heschl gyrus (HES), left putamen, left insula, bilateral paracentral lobular (PCL), right postcentral gyrus (PoCG), right precentral gyrus (PreCG), left precuneus and right supplementary motor area (SMA). Decreased dReHo values were also found in left PoCG, left PreCG, left SMA and left middle cingulate cortex (MCC). Meanwhile, alterations in INA present in brain regions were correlated with dopamine system (D2, FDOPA), norepinephrine transporter (NAT) and the vesicular acetylcholine transporter (VAChT) maps.

CONCLUSION

Static and dynamic INA abnormalities exist in first-episode OCD, having the potential to reveal the molecular characteristics. The results help to further understand the pathophysiological mechanism and provide alternative therapeutic targets of OCD.

Fluoxetine and Sertraline Inhibit Height Growth and Growth Hormone Signaling During Puberty

PURPOSE

The aim of this study was to examine the effect of fluoxetine and sertraline on height growth and insulin-like growth factor-1 (IGF-1) during puberty.

METHODS

In this 6-month cohort study, electronic medical records were used to identify 8- to 15-year-old participants, within 1 month of starting fluoxetine (n = 39) or sertraline (n = 27), and sexual maturation stages 2 to 4 were confirmed. Conditions that interfere with height growth led to exclusion. Participants underwent anthropometric assessments and phlebotomy. Healthy, unmedicated children (n = 36) also provided anthropometric data.

RESULTS

After the baseline height Z-score, sex, Tanner stage, daily selective serotonin reuptake inhibitor (SSRI) dose, and time were accounted for, the interaction effect of dose by time was inversely associated with height Z-score in SSRI-treated participants (β = -0.18; 95% confidence interval [CI]: -0.35, -0.02). Sertraline and fluoxetine did not differ in their effect on height growth. Compared with being unmedicated, SSRI treatment was associated with a smaller growth in height (time × dose 2-way interaction effect β = -1.30; 95% CI: -2.52, -0.09). The interaction effect of dose by time was significant for body mass index Z-score (β = 0.35; 95% CI: 0.06, 0.64) but not weight Z-score (β = 0.24; 95% CI: -0.01, 0.49). Body mass index Z-score increased more with sertraline compared with fluoxetine (time × dose × SSRI type 3-way interaction effect P < 0.05). SSRI dose was inversely associated with IGF-1 (β = -63.5; 95% CI: -112.2, -14.7) but not insulin growth factor binding protein-3 concentration (β = -207.3; 95% CI: -536.2, 121.5).

CONCLUSIONS

Fluoxetine and sertraline reduce height gain and IGF-1 concentration, in a dose-dependent manner. Longer-term studies are necessary.

Dorsal raphe dopaminergic neurons target CaMKII+ neurons in dorsal bed nucleus of the stria terminalis for mediating depression-related behaviors

Dopamine (DA) neurons play a crucial role in the development and manifestation of depression, as well as in response to antidepressant treatments. While the function of the predominantly distributed DA neurons in the ventral tegmental area (VTA) is well established, the contribution of a small fraction of DA neurons in the dorsal raphe nucleus (DRN) during depression remains unclear. In this study, we found that chronic unpredictable stress (CUS) induces depression-related behaviors and decreases spontaneous firing rates, excitatory and inhibitory postsynaptic currents of DA neurons in the DRN associated with reduced excitatory synaptic transmission in male and female mice. The chemogenetic inhibition of DA neurons in the DRN produces depressive phenotypes. Conversely, their activation completely reversed the anhedonic and despair behaviors induced by CUS. Furthermore, we showed that a DRN dopaminergic projecting to the dorsal bed nucleus of the stria terminalis (dBNST) selectively controls depressive behaviors by influencing the neural activity and N-methyl-D-aspartate receptor (NMDAR) mediating EPSC of calcium/calmodulin-dependent protein kinase II+ (CaMKII+) target neurons by regulating dopamine neurotransmitter and dopamine receptor 2 (DR2) in the dBNST. Overall, these findings highlight the essential role of the DRNDA → dBNSTCaMKII+ neural circuit in bi-directionally mediating stress-induced depression-related behaviors. Our findings indicate that DRN DA neurons are a key component of the neural circuitry involved in regulating depression-related behaviors, making them a potential therapeutic target for depression.

Lacticaseibacillus rhamnosus KY16 Improves Depression by Promoting Intestinal Secretion of 5-HTP and Altering the Gut Microbiota

Increasing research suggests a connection between gut microbiota and depressive disorders. Targeted changes to the intestinal flora may contribute to alleviating anxiety and depression. This study aimed to identify probiotics that could attenuate stress-induced abnormal behavior and explore potential mechanisms. The administration of LR.KY16 significantly reduced stress-induced abnormal behaviors and physiological dysfunction. The mechanism may be via regulating the structure of the intestinal microbiota in mice, increasing the abundance of Akkermansia muciniphila, prompting enterochromaffin cells to secrete 5-HTP in the gut, which enters the brain through the bloodstream and promotes the synthesis of 5-HT in the brain, and then activates brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) through the 5-HT1A receptor. In addition, LR.KY16 also increased the expression of claudin-7, occludin, and zonula occludens-1 (ZO-1) in the colon, inhibited microglial M1 polarization, and inhibited systemic inflammation.

Plasma alpha-trypsin inhibitor heavy chain 4 as an age-specific biomarker in the diagnosis and treatment of major depressive disorder

Background

The diagnosis of major depressive disorder (MDD) mainly depends on subjective clinical symptoms, without an acceptable objective biomarker for the clinical application of MDD. Inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) showed a high specificity as biomarker for the diagnosis and treatment of MDD. The present study aimed to investigate differences in plasma ITIH4 in two different aged MDD patients and underlying pathological mechanisms of plasma ITIH4 in the occurrence and development of MDD.

Methods

Sixty-five adult MDD patients, 51 adolescent MDD patients, and 64 healthy controls (HCs) were included in the present study. A 14-days' antidepressive treatment was conducted in all MDD patients. Psychological assessments were performed and plasma ITIH4 and astrocyte-related markers were detected for all participants.

Results

(1) Plasma levels of ITIH4 in adult MDD patients were significantly higher than adolescent MDD patients and HCs, and significantly increased plasma ITIH4 levels was observed in adolescent MDD patients compared with HCs (2). There were positive correlations between plasma ITIH4 levels and 24-item Hamilton Depression Scale (HAMD-24) scores and plasma glial fibrillary acidic protein (GFAP) levels in MDD patients, however, plasma ITIH4 levels were significantly correlated with age just in adult MDD patients (3). Plasma ITIH4 showed area under the curve values of 0.824 and 0.729 to differentiate adult MDD patients and adolescent MDD patients from HCs, respectively (4). There was significant decrease in plasma levels of ITIH4 between before and after antidepressive treatment in adult MDD patients, but not in adolescent MDD patients (5). Changed value of ITIH4 levels were correlated with the changed value of GFAP levels and changed rate of HAMD-24 scores in adult MDD patients following antidepressive treatment.

Conclusion

Plasma ITIH4 may be potential plasma biomarkers of MDD with age-related specificity, which was associated with depressive symptoms astrocyte-related pathologic changes, and antidepressive treatment efficacy.

Association between exposure to antidepressants and stimulants and age at onset of mania or psychosis: A retrospective population-based cohort study

This study investigated the impact of prior antidepressant and stimulant exposure on the age at onset (AAO) of first episode mania (FEM) or psychosis (FEP). Patients with FEP and FEM born after 1985 in Olmsted County, Minnesota, were identified using the Rochester Epidemiology Project. Duration and peak dose of antidepressant and stimulant exposure were quantified by review of the electronic health record. Peak doses were converted to defined daily dose (DDD), and cumulative exposure was calculated as DDD multiplied by treatment duration. Linear models were used to assess relationships between AAO with any exposures, and cumulative antidepressant and stimulant exposures. A total of 190 FEM/FEP patients (mean AAO=20.8 ± 3.7 years) were included. There was no significant difference in AAO with vs. without exposure to antidepressants or stimulants. Cumulative antidepressant exposure correlated with a later AAO in overall sample (r = 0.28, p < 0.001), and in FEP (r = 0.33, p < 0.001). No significant correlation emerged between cumulative stimulant exposure and AAO. Multivariable modeling confirmed that cumulative antidepressant exposure (Estimate=2.42, 95 %CI=1.66-3.18, p < 0.001), but not cumulative stimulant exposure (Estimate=-0.04, 95 %CI=-1.10-1.02, p = 0.94), was associated with later AAO. Antidepressant and stimulant exposures were not associated with earlier AAO. However, cumulative antidepressant exposure was associated with later AAO. Limitations include retrospective design and relatively small sample size. Our findings may inform adolescent treatment recommendations when assessing risk for psychotropic-related adverse events. Further risk modeling investigations of antidepressants and stimulants with larger sample sizes are needed to explore the role of antidepressant and stimulant exposure in the trajectory leading to FEM/FEP.

The Impact of Development on Antidepressant and Placebo Response in Anxiety Disorders: A Bayesian Hierarchical Meta-Analytic Examination of Randomized Controlled Trials in Children, Adolescents, and Adults

Background: Understanding how development influences medication and placebo responses in anxiety disorders could inform treatment decisions, including age-specific first- versus second-line psychopharmacological interventions. Objective: To meta-analytically compare the trajectory of selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and placebo response in youth and adults with anxiety disorders. Methods: Weekly symptom severity data were extracted from prospective, randomized, parallel-group, placebo-controlled trials of SSRIs and SNRIs in children, adolescents, and adults with anxiety disorders (generalized, separation, and social anxiety disorders as well as panic disorder). Treatment response was modeled for the standardized change in continuous measures of anxiety using a Bayesian hierarchical model. Change in symptom severity was evaluated as a function of time, and post hoc analyses were conducted to determine the sensitivity of these results across sample heterogeneity and alternative functional forms. Results: Data were included from 11 trials of youth (SSRI, κ = 7; SNRI, κ = 4) and 71 studies of adults (SSRI, κ = 46; SNRI, κ = 25). In total, 1067 youth participated in SSRI trials and 1024 in SNRI trials. In total, 10,826 adults participated in SSRI trials (placebo, n = 5367; SSRI n = 5,459) and 6232 in SNRI trials (placebo, n = 3,128; SNRI n = 3,094). A logarithmic model best described the response. Placebo response was similar in youth and adults (mean difference = -1.98 ± 6.21, 95% credible interval [CrI]: -10.2 to 14.2, p = 0.750), and statistically significant improvement from baseline emerged by week 2 in both adults (mean difference: -18.34 + 1.017, 95% CrI: -20.3 to 16.3, p < 0.001) and youth (mean difference: -23.74 + 3.736, 95% CrI: -31.1 to -16.4, p < 0.001). SSRIs produced similar improvements for youth and adults (p = 0.129), but SNRIs produced slower improvement in youth than adults (p = 0.018). Conclusions: Antidepressant-related improvement occurs early in youth and adults with anxiety disorders. SSRI response is similar in adults and youth; however, SNRIs produce greater responses in adults than youth, potentially representing a developmental effect.

Efficacy of selective serotonin reuptake inhibitors-related antidepressants in Alzheimer's disease: a meta-analysis

OBJECTIVE

To study the effects of selective serotonin reuptake inhibitors (SSRIs) on cognitive functions, mental improvements, and adverse effects in patients with Alzheimer's disease (AD).

METHODS

Registered in INPLASY (INPLASY202450004), five drugs (citalopram, s-citalopram, quetiapine, olanzapine, and sertraline) were selected as representatives. A comprehensive search was conducted in PubMed, EMBASE, Web of Science, and the Cochrane Library up to May 15, 2024. Search terms were combined using Boolean operators, specifically 'AND' between different categories (e.g., 'Alzheimer's Disease' AND 'SSRIs') and 'OR' within the same category (e.g., 'citalopram OR s-citalopram OR quetiapine OR olanzapine OR sertraline'), to ensure a thorough retrieval of relevant studies. The selection followed rigorous inclusion and exclusion criteria for meta-analysis.

RESULTS

Fourteen articles from 1118 were selected for meta-analysis. The indicators, including Neuropsychiatric Inventory (NPI), Mini-Mental State Examination (MMSE), Brief Psychiatric Rating Scale (BPRS), and Cornell Scale for Depression in Dementia (CSDD), were used to assess the effects of the drugs on AD treatment. According to the results of NPI, CSDD, BPRS, MMSE, and security assessments, the five antidepressants have significant advantages in AD treatment compared with placebo, while the MMSE of the patient treated with the antidepressants did not show notable changes compared with patients treated only with placebo. Statistical analyses were conducted using Review Manager 5.3, employing random-effects models to account for study heterogeneity and sensitivity analyses to test the robustness of our findings.

CONCLUSION

This study suggests that SSRI-related antidepressants have great potential values in AD treatment, and further research on the application of SSRI-related antidepressants in AD treatment is necessary.

Low-frequency Transcranial Magnetic Stimulation Ameliorates Anhedonic Behaviors and Regulates the Gut Microbiome in Mice Exposed to Chronic Unpredictable Mild Stress

Objective

This paper presents a preliminary study on whether low-frequency transcranial magnetic stimulation (LF-TMS) can modulate the gut microbiota in mice with chronic unpredictable mild stress (CUMS).

Methods

Mice received LF-TMS (1 Hz, 20 mT) for 28 consecutive days under chronic unpredictable mild stress (CUMS). The composition of gut microbiota of stool samples were tested.

Results

CUMS caused significant changes in gut microbiotas, specifically in community diversity of gut microbiotas (P < .05). Compared with the stressed group mice, the Chao1 index (P < .05), Observed species index (P < .05), Faith's PD index (P < .05) and Shannon index (P < .05) of the LF-TMS treatment group were significantly increased. Furthermore, 1 Hz LF-TMS-treatment partially recovered chronic stress induced changes of microbiotas, such as the abundance of Chloroflexi, Actinobacteria.

Conclusion

These results manifested that LF-TMS treatment can improve the anhedonic behaviors caused by CUMS in mice, which are connected with regulating the related intestinal microbial community disturbance, including species diversity, structure of gut microbiota, and species composition.

Gene-based drug therapy for children and youth treated with psychoactive medications

Psychoactive medications are increasingly used to treat children and youth with mental health conditions, but individual variations in response highlight the need for precision medicine. Pharmacogenetic (PGx) testing is a key component of precision medicine. The number of commercial pharmacogenetic testing companies promoting PGx, with the promise of achieving individualized and effective treatment of mental health conditions, has grown exponentially in recent years. Scientific evidence supporting the use of PGx to manage mental health conditions is limited, especially for paediatric populations. This practice point outlines steps guiding the use and interpretation of PGx testing for psychoactive medications in clinical settings, along with key supportive resources. Practice guidelines have been developed for variants in pharmacogenes encoding cytochrome P450 drug-metabolizing enzymes (e.g., CYP2C19, CYP2D6, CYP2C9) as one determinant of drug concentrations in blood, which can support both drug choice and dosing strategy for certain anti-psychotics, anti-depressants, and anti-epileptics. Adverse drug reactions to some anti-epileptic drugs (e.g., carbamazepine and phenytoin) have been associated with certain human leukocyte antigen types and variants in DNA polymerase gamma (POLG; valproic acid). Evidence remains limited for genetic variants of drug target proteins, making it challenging to identify patients with altered treatment responses at a therapeutic blood concentration.

The effectiveness of the lorazepam challenge test in pediatric catatonia: A multisite retrospective cohort study

OBJECTIVE

Catatonia is a neuropsychiatric disorder associated with changes in behavior and affect. In adults, catatonia can respond rapidly to treatment with benzodiazepines as part of the "lorazepam challenge test." The acute effectiveness of benzodiazepine treatment in pediatric catatonia, however, has received less study. This study reports catatonia severity as measured by the Bush Francis Catatonia Rating Scale (BFCRS) in pediatric patients before and after treatment with lorazepam.

METHODS

Multicenter retrospective cohort study from 1/1/2018 to 6/1/2023 of patients aged 18 and younger with a clinical diagnosis of catatonia and assessment using the BFCRS before and after treatment with lorazepam.

RESULTS

Among 54 patients, median age was 16, and 26 (48.1 %) were female. Neurodevelopmental disabilities were present in 24 (44.4 %) of patients. Prior to treatment, patients had a mean BFCRS score of 16.6 ± 6.1, which significantly reduced to 9.5 ± 5.3 following treatment with lorazepam (mean paired difference 7.1; t = 9.0, df = 53, p < 0.001), representing a large effect size (Hedges's g = 1.20; 95 % CI: 0.85 to 1.55). No significant association was found between lorazepam dose or route of administration and clinical response, nor were age, sex, study site, the presence of a neurodevelopmental disorder, the presence of hyperactive catatonic features, or the time between treatment and reassessment associated with post-treatment BFCRS.

CONCLUSIONS

Lorazepam resulted in a rapid improvement in BFCRS score in pediatric patients, with a large effect size. Further research is needed into optimal dosing and route of administration of the lorazepam challenge test in pediatric patients.

La pharmacothérapie en fonction des gènes chez les enfants et les adolescents qui prennent des médicaments psychoactifs

Les médicaments psychoactifs sont de plus en plus utilisés pour traiter les enfants et les adolescents ayant des troubles de santé mentale, mais la variabilité des réponses individuelles fait ressortir l'importance d'une médecine personnalisée. Les tests pharmacogénétiques sont un volet important d'un tel type de médecine. Le nombre d'entreprises de tests pharmacogénétiques commerciaux qui font la promotion de tests de ce genre et promettent un traitement efficace et individualisé des troubles de santé mentale se multiplie depuis quelques années. Les preuves scientifiques en appui à l'utilisation de la pharmacogénétique sont limitées, particulièrement dans les populations pédiatriques. Le présent point de pratique souligne les étapes qui orientent le recours à ces tests pour la prise de médicaments psychoactifs en milieu clinique et présente des ressources de soutien importantes. Il existe des directives cliniques sur les variants des pharmacogènes qui encodent les enzymes de métabolisation du cytochrome P450 (p. ex., CYP2C19, CYP2D6, CYP2C9), lesquels sont l'un des déterminants des concentrations pharmacologiques dans le sang et peuvent appuyer à la fois le choix du médicament et la stratégie posologique de certains antipsychotiques, antidépresseurs et antiépileptiques. Les effets indésirables de certains médicaments antiépileptiques (p. ex., la carbamazépine et la phénytoïne) sont associés à certains types d'antigènes d'histocompatibilité humaine et à des variants de l'ADN polymérase gamma (POLG; acide valproïque). Les données probantes sont limitées à l'égard des variants génétiques des protéines qui ciblent les médicaments, et c'est pourquoi il est difficile de déterminer quels patients présenteraient une réponse altérée au traitement à une concentration sanguine thérapeutique.

Xiaoyao Pills, a Chinese patent medicine, treats mild and moderate depression: A randomized clinical trial combined with DNA methylation analysis

BACKGROUND

Xiaoyao pills (XYP) is a commercial Chinese patent medicine used in the treatment of depression. However, the mechanisms underlying its therapeutic effects, as well as the patients who can benefit from XYP, have not been evaluated so far.

OBJECTIVES

To this end, we conducted a double-blinded, random, and placebo-controlled clinical trial of orally administered XYP in patients with depression.

METHODS

The 17-item Hamilton Depression Rating Scale (HAMD-17) scores were recorded at baseline, and every 2 weeks after the start of treatment. To further elucidate the epigenetic mechanism of XYP, we performed mRNA sequencing and genome-wide DNA methylation sequencing using peripheral blood leukocytes of patients and healthy.

RESULTS

XYP effectively alleviated the symptoms in patients with mild or moderate depressive disorders, particularly that of psychomotor retardation. XYP restored aberrant gene expression and DNA methylation patterns associated with depression, and the normalization of DNA methylation correlated with downregulation of several genes. In addition, altered DNA methylation levels in the XYP-treated samples were attributed to increased expression of the DNA methyltransferase DNMT1.

CONCLUSIONS

Our study provides new insights into the epigenetic mechanism underlying depression and the therapeutic effects of XYP, along with an experimental basis for using XYP in the treatment of depression.

TRIAL REGISTRATION INFORMATION

The name of the registry and number: U.S.

CLINICAL TRIALS REGISTRY

The link to the registration: ClinicalTrials.gov ISRCTN12746343 (https://www.isrctn.com/ISRCTN12746343). The name of the trial register is "Efficacy and safety of the Xiaoyao pill for improving the clinical symptoms of stagnation of liver qi (chi) and spleen deficiency". The clinical trial registration number is ISRCTN12746343.

The multifaceted effects of fluoxetine treatment on cognitive functions

Fluoxetine, the prototypical selective serotonin reuptake inhibitor (SSRI), is widely used to treat major depressive disorder (MDD) and a variety of other central nervous system conditions, primarily due to its established clinical safety profile. Although its efficacy in treating depression is well-recognized, the impact of fluoxetine on cognitive functions remains inconsistent and elusive. In this review, we first examine the well-substantiated biological mechanisms underlying fluoxetine's antidepressant effects, which include serotonin reuptake inhibition and activation of TrkB receptors-key to brain-derived neurotrophic factor (BDNF) signaling. Subsequently, we delve into the cognitive side effects observed in both preclinical and clinical studies, affecting domains such as memory, attention, and executive functions. While certain studies indicate cognitive improvements in patients with underlying disorders, there is also evidence of negative effects, influenced by variables like gender, duration of treatment, age, disease pathology, and the specifics of cognitive testing. Significantly, the negative cognitive outcomes reported in preclinical research often involve healthy, non-diseased animals. This review underscores the necessity for heightened caution in fluoxetine prescription and further investigation into its potentially detrimental cognitive effects, even when used prophylactically.

Major challenges in youth psychopathology: treatment-resistant depression. A narrative review

Major depressive disorder (MDD) represents a major health issue in adolescents and young adults, leading to high levels of disability and profoundly impacting overall functioning. The clinical presentation of MDD in this vulnerable age group may slightly differ from what can be observed in adult populations, and psychopharmacological strategies do not always lead to optimal response. Resistance to antidepressant treatment has a prevalence estimated around 40% in youths suffering from MDD and is associated with higher comorbidity rates and suicidality. Several factors, encompassing biological, environmental, and clinical features, may contribute to the emergence of treatment-resistant depression (TRD) in adolescents and young adults. Furthermore, TRD may underpin the presence of an unrecognized bipolar diathesis, increasing the overall complexity of the clinical picture and posing major differential diagnosis challenges in the clinical practice. After summarizing current evidence on epidemiological and clinical correlates of TRD in adolescents and young adults, the present review also provides an overview of possible treatment strategies, including novel fast-acting antidepressants. Despite these pharmacological agents are promising in this population, their usage is expected to rely on risk-benefit ratio and to be considered in the context of integrated models of care.

Omega-3 alleviates behavioral and molecular changes in a mouse model of stress-induced juvenile depression

Introduction

Depression is increasingly diagnosed in adolescence, necessitating specific prevention and treatment methods. However, there is a lack of animal models mimicking juvenile depression. This study explores a novel model using ultrasound (US) stress in juvenile mice.

Methods

We employed the US stress model in one-month-old C57/BL6 mice, exposing them to alternating ultrasound frequencies (20-25 kHz and 25-45 kHz) for three weeks. These frequencies correspond to negative and neutral emotional states in rodents and can induce a depressive-like syndrome. Concurrently, mice received either an omega-3 food supplement (FS) containing eicosapentaenoic acid (EPA; 0.55 mg/kg/day) and docosahexaenoic acid (DHA; 0.55 mg/kg/day) or a vehicle. Post-stress, we evaluated anxiety- and depressive-like behaviors, blood corticosterone levels, brain expression of pro-inflammatory cytokines, and conducted metabolome analysis of brain, liver and blood plasma.

Results

US-exposed mice treated with vehicle exhibited decreased sucrose preference, a sign of anhedonia, a key feature of depression, increased anxiety-like behavior, elevated corticosterone levels, and enhanced TNF and IL-1β gene expression in the brain. In contrast, US-FS mice did not display these changes. Omega-3 supplementation also reduced anxiety-like behavior in non-stressed mice. Metabolomic analysis revealed US-induced changes in brain energy metabolism, with FS increasing brain sphingomyelin. Liver metabolism was affected by both US and FS, while plasma metabolome changes were exclusive to FS. Brain glucose levels correlated positively with activity in anxiety tests.

Conclusion

Chronic omega-3 intake counteracted depressive- and anxiety-like behaviors in a US model of juvenile depression in mice. These effects likely stem from the anti-inflammatory properties of the supplement, suggesting potential therapeutic applications in juvenile depression.

Comparing the effect of fluoxetine, escitalopram, and sertraline, on the level of BDNF and depression in preclinical and clinical studies: a systematic review

Brain-derived neurotrophic factor (BDNF) dysfunction is one of the most important mechanisms underlying depression. It seems that selective serotonin reuptake inhibitors (SSRIs) improve depression via affecting BDNF level. In this systematic review, for the first time, we aimed to review the effect of three SSRIs including fluoxetine, escitalopram, and sertraline, on both depression and BDNF level in preclinical and clinical studies. PubMed electronic database was searched, and 193 articles were included in this study. After reviewing all manuscripts, only one important difference was found: subjects. We found that SSRIs induce different effects in animals vs. humans. Preclinical studies showed many controversial effects, while human studies showed only two effects: improvement of depression, with or without the improvement of BDNF. However, most studies used chronic SSRIs treatment, while acute SSRIs were not effectively used and evaluated. In conclusion, it seems that SSRIs are reliable antidepressants, and the improvement effect of SSRIs on depression is not dependent to BDNF level (at least in human studies).

Bright Light Therapy as Add-On to Inpatient Treatment in Youth With Moderate to Severe Depression: A Randomized Clinical Trial

Importance

Major depressive disorder is one of the most common mental disorders among adolescents, entailing severe, long-term psychosocial impairment and a high risk of chronicity. In view of the large number of patients requiring treatment, along with insufficient treatment responses with small effect sizes, innovative adjunctive treatment strategies are urgently needed.

Objective

To investigate whether the effect of adolescent psychiatric inpatient treatment as usual for major depressive disorder can be enhanced by simultaneous use of morning bright light therapy.

Design, Setting, and Participants

This was a double-blind, placebo-controlled randomized parallel-group trial with enrollment between March 2018 and November 2020 and follow-up completed in May 2021. The study took place among inpatients at 4 university hospitals for child and adolescent psychiatry across Germany. Of 248 eligible youth aged 12 to 18 years fulfilling ICD-10 criteria for major depressive disorder, 227 were randomized to bright light therapy (n = 116) or placebo red light (n = 111); 151 participants completed the study.

Interventions

Up to 20 sessions of either morning bright light therapy with an intensity of 10 000 lux or placebo red light (100 lux) in addition to multimodal inpatient treatment as usual over 4 weeks.

Main Outcomes and Measures

The primary outcome was the change in Beck Depression Inventory-II (BDI-II) score from baseline to posttreatment in the intention-to-treat sample.

Results

Among the 224 patients included in the intention-to-treat analyses (192 girls and 32 boys; mean [SD] age, 15.5 [1.4] years), the mean (SD) BDI-II score at baseline was 37.3 (8.7). BDI-II scores were significantly reduced after 4 weeks (postassessment) by a mean of -7.5 (95% CI, -9.0 to -6.0; Hedges g = 0.71). Bright light therapy had no impact on this change (no significant group × time effect). Loss to follow-up was 31% (n = 69) at 16 weeks and 49% (n = 110) at 28 weeks. There were 10 serious adverse events throughout the whole trial, which were not considered related to study treatment.

Conclusions and Relevance

The findings in this study did not indicate superiority of bright light therapy over placebo red light therapy in a large sample of adolescent inpatients with moderate or severe major depressive disorder. Both groups benefited equally from treatment as usual, showing relevant symptom reduction.

Trial Registration

German Clinical Trials Register: DRKS00013188.

Placebo effects in randomized trials of pharmacological and neurostimulation interventions for mental disorders: An umbrella review

There is a growing literature exploring the placebo response within specific mental disorders, but no overarching quantitative synthesis of this research has analyzed evidence across mental disorders. We carried out an umbrella review of meta-analyses of randomized controlled trials (RCTs) of biological treatments (pharmacotherapy or neurostimulation) for mental disorders. We explored whether placebo effect size differs across distinct disorders, and the correlates of increased placebo effects. Based on a pre-registered protocol, we searched Medline, PsycInfo, EMBASE, and Web of Knowledge up to 23.10.2022 for systematic reviews and/or meta-analyses reporting placebo effect sizes in psychopharmacological or neurostimulation RCTs. Twenty meta-analyses, summarising 1,691 RCTs involving 261,730 patients, were included. Placebo effect size varied, and was large in alcohol use disorder (g = 0.90, 95% CI [0.70, 1.09]), depression (g = 1.10, 95% CI [1.06, 1.15]), restless legs syndrome (g = 1.41, 95% CI [1.25, 1.56]), and generalized anxiety disorder (d = 1.85, 95% CI [1.61, 2.09]). Placebo effect size was small-to-medium in obsessive-compulsive disorder (d = 0.32, 95% CI [0.22, 0.41]), primary insomnia (g = 0.35, 95% CI [0.28, 0.42]), and schizophrenia spectrum disorders (standardized mean change = 0.33, 95% CI [0.22, 0.44]). Correlates of larger placebo response in multiple mental disorders included later publication year (opposite finding for ADHD), younger age, more trial sites, larger sample size, increased baseline severity, and larger active treatment effect size. Most (18 of 20) meta-analyses were judged 'low' quality as per AMSTAR-2. Placebo effect sizes varied substantially across mental disorders. Future research should explore the sources of this variation. We identified important gaps in the literature, with no eligible systematic reviews/meta-analyses of placebo response in stress-related disorders, eating disorders, behavioural addictions, or bipolar mania.

Rationale and design for a pragmatic randomized trial to assess gene-based prescribing for SSRIs in the treatment of depression

Specific selective serotonin reuptake inhibitors (SSRIs) metabolism is strongly influenced by two pharmacogenes, CYP2D6 and CYP2C19. However, the effectiveness of prospectively using pharmacogenetic variants to select or dose SSRIs for depression is uncertain in routine clinical practice. The objective of this prospective, multicenter, pragmatic randomized controlled trial is to determine the effectiveness of genotype-guided selection and dosing of antidepressants on control of depression in participants who are 8 years or older with ≥3 months of depressive symptoms who require new or revised therapy. Those randomized to the intervention arm undergo pharmacogenetic testing at baseline and receive a pharmacy consult and/or automated clinical decision support intervention based on an actionable phenotype, while those randomized to the control arm have pharmacogenetic testing at the end of 6-months. In both groups, depression and drug tolerability outcomes are assessed at baseline, 1 month, 3 months (primary), and 6 months. The primary end point is defined by change in Patient-Reported Outcomes Measurement Information System (PROMIS) Depression score assessed at 3 months versus baseline. Secondary end points include change inpatient health questionnaire (PHQ-8) measure of depression severity, remission rates defined by PROMIS score < 16, medication adherence, and medication side effects. The primary analysis will compare the PROMIS score difference between trial arms among those with an actionable CYP2D6 or CYP2C19 genetic result or a CYP2D6 drug-drug interaction. The trial has completed accrual of 1461 participants, of which 562 were found to have an actionable phenotype to date, and follow-up will be complete in April of 2024.

Re-thinking the treatment of depression: have we been misinformed about antidepressants? A webinar discussion with Irving Kirsch, Ph.D. and Michael D. Yapko, Ph.D

This article provides an edited transcript of a moderated discussion between depression experts Irving Kirsch and Michael Yapko regarding the role of antidepressants in the treatment of major depression. It includes references to the role of expectancy and the merits of hypnosis in treatment. This presentation was sponsored by MindsetHealth, an Australian-based digital therapeutics company (mindsethealth.com) and took place online on March 28, 2023. As a webinar offered at no cost, it was open to anyone with an interest in the subject. Dr. Kirsch described his landmark research on the placebo effect and its curious relationship to the presumed merits of antidepressant medications. Dr. Yapko discussed the limitations of drug treatment based on the substantial evidence indicating that depression is much more a social problem than a medical one. The moderator for this discussion is Claire Davidson, who serves as the Research Lead at MindsetHealth. Drs. Kirsch and Yapko both serve on the MindsetHealth Scientific Advisory Board.

Dexmedetomidine Inhibits Paraventricular Corticotropin-releasing Hormone Neurons that Attenuate Acute Stress-induced Anxiety-like Behavior in Mice

BACKGROUND

Dexmedetomidine has repeatedly shown to improve anxiety, but the precise neural mechanisms underlying this effect remain incompletely understood. This study aims to explore the role of corticotropin-releasing hormone-producing hypothalamic paraventricular nucleus (CRHPVN) neurons in mediating the anxiolytic effects of dexmedetomidine.

METHODS

A social defeat stress mouse model was used to evaluate the anxiolytic effects induced by dexmedetomidine through the elevated plus maze, open-field test, and measurement of serum stress hormone levels. In vivo Ca2+ signal fiber photometry and ex vivo patch-clamp recordings were used to determine the excitability of CRHPVN neurons and investigate the specific mechanism involved. CRHPVN neuron modulation was achieved through chemogenetic activation or inhibition.

RESULTS

Compared with saline, dexmedetomidine (40 µg/kg) alleviated anxiety-like behaviors. Additionally, dexmedetomidine reduced CRHPVN neuronal excitability. Chemogenetic activation of CRHPVN neurons decreased the time spent in the open arms of the elevated plus maze and in the central area of the open-field test. Conversely, chemogenetic inhibition of CRHPVN neurons had the opposite effect. Moreover, the suppressive impact of dexmedetomidine on CRHPVN neurons was attenuated by the α2-receptor antagonist yohimbine.

CONCLUSIONS

The results indicate that the anxiety-like effects of dexmedetomidine are mediated via α2-adrenergic receptor-triggered inhibition of CRHPVN neuronal excitability in the hypothalamus.

EDITOR’S PERSPECTIVE

Antidepressant-induced membrane trafficking regulates blood-brain barrier permeability

As the most prescribed psychotropic drugs in current medical practice, antidepressant drugs (ADs) of the selective serotonin reuptake inhibitor (SSRI) class represent prime candidates for drug repurposing. The mechanisms underlying their mode of action, however, remain unclear. Here, we show that common SSRIs and selected representatives of other AD classes bidirectionally regulate fluid-phase uptake at therapeutic concentrations and below. We further characterize membrane trafficking induced by a canonical SSRI fluvoxamine to show that it involves enhancement of clathrin-mediated endocytosis, endosomal system, and exocytosis. RNA sequencing analysis showed few fluvoxamine-associated differences, consistent with the effect being independent of gene expression. Fluvoxamine-induced increase in membrane trafficking boosted transcytosis in cell-based blood-brain barrier models, while a single injection of fluvoxamine was sufficient to enable brain accumulation of a fluid-phase fluorescent tracer in vivo. These findings reveal modulation of membrane trafficking by ADs as a possible cellular mechanism of action and indicate their clinical repositioning potential for regulating drug delivery to the brain.

Marine natural products: potential agents for depression treatment

Depression is a common psychiatric disorder. Due to the disadvantages of current clinical drugs, including poor efficacy and unnecessary side effects, research has shifted to novel natural products with minimal or no adverse effects as therapeutic alternatives. The ocean is a vast ecological home, with a wide variety of organisms that can produce a large number of natural products with unique structures, some of which have neuroprotective effects and are a valuable source for the development of new drugs for depression. In this review, we analyzed preclinical and clinical studies of natural products derived from marine organisms with antidepressant potential, including the effects on the pathophysiology of depression, and the underlying mechanisms of these effects. It is expected to provide a reference for the development of new antidepressant drugs.

Machine Learning-Based Prediction of Escitalopram and Sertraline Side Effects With Pharmacokinetic Data in Children and Adolescents

Selective serotonin reuptake inhibitors (SSRI) are the first-line pharmacologic treatment for anxiety and depressive disorders in children and adolescents. Many patients experience side effects that are difficult to predict, are associated with significant morbidity, and can lead to treatment discontinuation. Variation in SSRI pharmacokinetics could explain differences in treatment outcomes, but this is often overlooked as a contributing factor to SSRI tolerability. This study evaluated data from 288 escitalopram-treated and 255 sertraline-treated patients ≤ 18 years old to develop machine learning models to predict side effects using electronic health record data and Bayesian estimated pharmacokinetic parameters. Trained on a combined cohort of escitalopram- and sertraline-treated patients, a penalized logistic regression model achieved an area under the receiver operating characteristic curve (AUROC) of 0.77 (95% confidence interval (CI): 0.66-0.88), with 0.69 sensitivity (95% CI: 0.54-0.86), and 0.82 specificity (95% CI: 0.72-0.87). Medication exposure, clearance, and time since the last dose increase were among the top features. Individual escitalopram and sertraline models yielded an AUROC of 0.73 (95% CI: 0.65-0.81) and 0.64 (95% CI: 0.55-0.73), respectively. Post hoc analysis showed sertraline-treated patients with activation side effects had slower clearance (P = 0.01), which attenuated after accounting for age (P = 0.055). These findings raise the possibility that a machine learning approach leveraging pharmacokinetic data can predict escitalopram- and sertraline-related side effects. Clinicians may consider differences in medication pharmacokinetics, especially during dose titration and as opposed to relying on dose, when managing side effects. With further validation, application of this model to predict side effects may enhance SSRI precision dosing strategies in youth.

Meeting 24-h movement behavior guidelines is linked to academic engagement, psychological functioning, and cognitive difficulties in youth with internalizing problems

BACKGROUND

This study aimed to investigate associations of meeting 24-h movement behavior (24-HMB: physical activity [PA], screen time [ST] in the school-aged youth, and sleep) guidelines with indicators of academic engagement, psychological functioning, and cognitive function in a national representative sample of U.S. youth.

METHODS

In this cross-sectional study, 1794 participants aged 6 to 17 years old were included for multivariable logistic regression to determine the above-mentioned associations, while adjusting for sociodemographic and health covariates.

RESULTS

The proportion of participants who met 24-HMB guideline(s) varied greatly (PA+ ST+ sleep = 34 [weighted 1.17 %], PA + ST = 23 [weighted 1.72 %], PA + sleep = 52 [weighted 2.15 %], PA = 34 [weighted 2.88 %], ST = 142 [weighted 7.5 %], ST+ sleep = 209 [weighted 11.86 %], sleep = 725 [weighted 35.5 %], none = 575 [weighted 37.22 %]). Participants who met ST guideline alone and integrated (ST + Sleep and ST + sleep + PA) guidelines demonstrated the consistently beneficial associations with learning interest/curiosity, caring for school performance, completing required homework, resilience, cognitive difficulties, self-regulation (ps < 0.05).

CONCLUSION

Meeting 24-HMB guidelines in an isolated or integrative manner was associated with improved academic engagement, psychological functioning, and reduced cognitive difficulties. These findings highlight the importance of the promotion of 24-HMB guidelines in youth with internalizing problems. Future longitudinal studies are needed to investigate whether changes or modifications of meeting specific 24-HMB guidelines (especially ST) is beneficial for youth with internalizing problems.

Common changes in rat cortical gene expression after antidepressant drug treatment: Impacts on metabolism of polyamines, mRNA splicing, regulation of RAS by GAPs, neddylation and GPCR ligand binding

OBJECTIVES

This study sought to identify pathways affected by rat cortical RNA that were changed after treatment with fluoxetine or imipramine.

METHODS

We measured levels of cortical RNA in male rats using GeneChip® Rat Exon 1.0 ST Array after treatment with vehicle (0.9% NaCl), fluoxetine (10 mg/kg/day) or imipramine (20 mg/kg/day) for 28 days. Levels of coding and non-coding RNA in vehicle treated rats were compared to those in treated rats using ANOVA in JMP Genomics 13 and the Panther Gene Ontology Classification System was used to identify pathways involving the changed RNAs.

RESULTS

18,876 transcripts were detected; there were highly correlated changes in 1010 levels of RNA after both drug treatments that would principally affect the metabolism of polyamines, mRNA splicing, regulation of RAS by GAPs, neddylation and GPCR ligand binding. Using our previously published data, we compared changes in transcripts after treatment with antipsychotic and mood stabilising drugs.

CONCLUSIONS

Our study shows there are common, correlated, changes in coding and non-coding RNA in the rat cortex after treatment with fluoxetine or imipramine; we propose the pathways affected by these changes are involved in the therapeutic mechanisms of action of antidepressant drugs.

Current and Future Approaches to Pediatric Anxiety Disorder Treatment

This overview critically appraises the literature on the treatment of pediatric anxiety disorders. The two established treatments for these conditions comprise cognitive-behavioral therapy (CBT) and antidepressant medications. Many youths receiving these treatments fail to achieve remission, which creates a need for new treatments. After summarizing the literature on CBT and currently available medications, the authors describe research that lays a foundation for improvements in the treatment of pediatric anxiety disorders. This foundation leverages neuroscientific investigations, also described in the overview, which provide insights on mechanisms of successful treatment.

The genetic architecture of youth anxiety: a study protocol

BACKGROUND

Anxiety disorders are the most common psychiatric problems among Canadian youth and typically have an onset in childhood or adolescence. They are characterized by high rates of relapse and chronicity, often resulting in substantial impairment across the lifespan. Genetic factors play an important role in the vulnerability toward anxiety disorders. However, genetic contribution to anxiety in youth is not well understood and can change across developmental stages. Large-scale genetic studies of youth are needed with detailed assessments of symptoms of anxiety disorders and their major comorbidities to inform early intervention or preventative strategies and suggest novel targets for therapeutics and personalization of care.

METHODS

The Genetic Architecture of Youth Anxiety (GAYA) study is a Pan-Canadian effort of clinical and genetic experts with specific recruitment sites in Calgary, Halifax, Hamilton, Toronto, and Vancouver. Youth aged 10-19 (n = 13,000) will be recruited from both clinical and community settings and will provide saliva samples, complete online questionnaires on demographics, symptoms of mental health concerns, and behavioural inhibition, and complete neurocognitive tasks. A subset of youth will be offered access to a self-managed Internet-based cognitive behavioral therapy resource. Analyses will focus on the identification of novel genetic risk loci for anxiety disorders in youth and assess how much of the genetic risk for anxiety disorders is unique or shared across the life span.

DISCUSSION

Results will substantially inform early intervention or preventative strategies and suggest novel targets for therapeutics and personalization of care. Given that the GAYA study will be the biggest genomic study of anxiety disorders in youth in Canada, this project will further foster collaborations nationally and across the world.

Empowered and engaged: Group exercise for adolescent depression - perspectives from adolescents, parents and healthcare professionals

Objectives

Depression is increasing and is a leading cause of disease burden among adolescents. Available evidence-based treatments with medication or psychotherapy have modest effects. Aerobic exercise is a hopeful alternative as an augmenter or a stand-alone treatment. Qualitative studies have shown that participants in group exercise for adolescent depression experienced improved mood and a sense of achievement, commitment and empowerment. This study aimed to explore not only adolescents' but also parents' and healthcare professionals' experiences of a group exercise intervention for adolescents with depression.

Methods

Nine adolescents who had participated in a group aerobic exercise intervention for 12 weeks, eight parents and two healthcare professionals were interviewed. We used a latent qualitative content analysis with an inductive approach that resulted in nine sub-categories, three categories and an overarching theme.

Results

The experiences of a group exercise intervention for adolescents with depression were expressed in the overarching theme 'Group exercise for adolescent depression promotes empowerment and engagement in everyday life', based on three categories: exercise alleviates depressive symptoms, exercise contributes to balance in life and exercise promotes self-esteem. However, there was variation in our results, in that not all participants experienced improvements from exercising. Adolescents described more varied experiences, while parents and healthcare professionals mainly expressed positive views.

Conclusions

Our findings suggest that group exercise for adolescent depression promotes empowerment and engagement in everyday life, according to adolescents, and more clearly so according to parents and healthcare professionals.

Mobilization of the innate immune response by a specific immunostimulant β-glucan confers resistance to chronic stress-induced depression-like behavior by preventing neuroinflammatory responses

Pre-stimulation of the innate immune response is an effective strategy to prevent depression-like phenotypes in animals. However, the use of conventional immunostimulants may cause adverse effects. Therefore, the search for agents that stimulate the innate immune response but do not induce a pro-inflammatory response could be a new research direction for the prevention of depression. β-glucan is a polysaccharide from Saccharomyces cerevisiae with unique immunomodulatory activity in microglia without eliciting a pro-inflammatory response that could lead to tissue damage. This suggests that β-glucan may be a suitable drug that can be used to prevent depression-like phenotypes. Our results showed that a single injection of β-glucan 1 day before stress exposure at a dose of 10 or 20 mg/kg, but notat a dose of 5 mg/kg, prevented depression-like behavior in mice treated with chronic unpredictable stress (CUS). This effect of β-glucan disappeared when the time interval between β-glucan and stress was extended from 1 day or 5 days to 10 days, which was rescued by a second injection 10 days after the first injection or by a repeated injection (4×, once daily) 10 days before stress exposure. A single β-glucan injection (20 mg/kg) 1 day before stress exposure prevented the CUS-induced increase in brain pro-inflammatory cytokines, and inhibition of the innate immune response by minocycline (40 mg/kg) abolished the preventive effect of β-glucan on CUS-induced depression-like behaviors and neuroinflammatory responses. These results suggest that β-glucan may prevent chronic stress-induced depression-like phenotypes and neuroinflammatory responses by stimulating the innate immune response.

An evidence gap map of interventions for noncommunicable diseases and risk factors among children and adolescents

Substance misuse, obesity, mental health conditions, type 1 diabetes, cancers, and cardiovascular and chronic respiratory diseases together account for 41% of disability-adjusted life years linked to noncommunicable diseases (NCDs) among children and adolescents worldwide. However, the evidence on risk factors and interventions for this age group is scarce. Here we searched four databases to generate an evidence gap map of existing interventions and research gaps for these risk factors and NCDs. We mapped 159 reviews with 2,611 primary studies; most (96.2%) were conducted in high-income countries, and only 100 studies (3.8%) were from low- and middle-income countries (LMICs). The efficacy of therapeutic interventions on biomarkers and adverse events for NCDs appears to be well evidenced. Interventions for mental health conditions appear to be moderately evidenced, while interventions for obesity and substance misuse appear to be moderate to very low evidenced. Priority areas for future research include evaluating digital health platforms to support primary NCD prevention and management, and evaluating the impact of policy changes on the prevalence of obesity and substance misuse. Our findings highlight the wide disparity of evidence between high-income countries and LMICs. There is an urgent need for increased, targeted financing to address the research gaps in LMICs.

Neuroproteomics: Unveiling the Molecular Insights of Psychiatric Disorders with a Focus on Anxiety Disorder and Depression

Anxiety and depression are two of the most common mental disorders worldwide, with a lifetime prevalence of up to 30%. These disorders are complex and have a variety of overlapping factors, including genetic, environmental, and behavioral factors. Current pharmacological treatments for anxiety and depression are not perfect. Many patients do not respond to treatment, and those who do often experience side effects. Animal models are crucial for understanding the complex pathophysiology of both disorders. These models have been used to identify potential targets for new treatments, and they have also been used to study the effects of environmental factors on these disorders. Recent proteomic methods and technologies are providing new insights into the molecular mechanisms of anxiety disorder and depression. These methods have been used to identify proteins that are altered in these disorders, and they have also been used to study the effects of pharmacological treatments on protein expression. Together, behavioral and proteomic research will help elucidate the factors involved in anxiety disorder and depression. This knowledge will improve preventive strategies and lead to the development of novel treatments.

Novel mechanism-based treatments for pediatric anxiety and depressive disorders

Pediatric anxiety and depressive disorders are common, can be highly impairing, and can persist despite the best available treatments. Here, we review research into novel treatments for childhood anxiety and depressive disorders designed to target underlying cognitive, emotional, and neural circuit mechanisms. We highlight three novel treatments lying along a continuum relating to clinical impact of the disorder and the intensity of clinical management required. We review cognitive training, which involves the lowest risk and may be applicable for problems with mild to moderate impact; psychotherapy, which includes a higher level of clinical involvement and may be sufficient for problems with moderate impact; and brain stimulation, which has the highest potential risks and is therefore most appropriate for problems with high impact. For each treatment, we review the specific underlying cognitive, emotional, and brain circuit mechanisms that are being targeted, whether treatments modify those underlying mechanisms, and efficacy in reducing symptoms. We conclude by highlighting future directions, including the importance of work that leverages developmental windows of high brain plasticity to time interventions to the specific epochs in childhood that have the largest and most enduring life-long impact.

β-glucan, a specific immuno-stimulant, produces rapid antidepressant effects by stimulating ERK1/2-dependent synthesis of BDNF in the hippocampus

A decline in microglia in the dentate gyrus of the hippocampus has recently been described as an important mechanism for the progression of depression. Reversal of this decline by innate immune system stimulants may represent a novel strategy to ameliorate the depressive phenotype in chronically stressed animals. β-glucan is a polysaccharide from Saccharomyces cerevisiae. It can efficiently stimulate microglia without inducing the production of pro-inflammatory cytokines. Therefore, β-glucan could be an ideal drug to ameliorate depressive phenotypes. In the present study, we found that a single injection of β-glucan reversed depression-like behaviors in mice induced by chronic unpredictable stress (CUS) in a dose-dependent manner, which was accompanied by a reversal of the CUS-induced decrease in brain-derived neurotrophic factor (BDNF) protein levels in the dentate gyrus. The crucial role of BDNF signaling in the antidepressant effect of β-glucan was demonstrated by experiments showing that infusion of an anti-BDNF antibody into dentate gyrus, construction of BDNF-Val68Met allele knock-in mice, or treatment with the BDNF receptor antagonist K252a abolished the antidepressant effect of β-glucan. The increased BDNF signaling induced by β-glucan was mediated by extracellular signal-regulated kinase1/2 (ERK1/2)-mediated BDNF synthesis, and inhibition of ERK1/2 by SL327 was able to abolish the antidepressant effect of β-glucan. Moreover, inhibition or depletion of microglia by minocycline or PLX3397 abolished the reversal effect of β-glucan on CUS-induced depression-like behaviors and CUS-induced impairment of ERK1/2-BDNF signaling. These results suggest that β-glucan exhibits antidepressant effects by stimulating microglia-mediated activation of ERK1/2 and synthesis of BDNF in the hippocampus.

Psilocybin-assisted therapy for depression: A systematic review and dose-response meta-analysis of human studies

Psilocybin is increasingly studied for its antidepressant effect, but its optimal dosage for depression remains unclear. We conducted a systematic review and a dose-response meta-analysis to find the optimal dosage of psilocybin to reduce depression scores. Following our protocol (CRD 42022220190) multiple electronic databases were searched from their inception until February 2023, to identify double-blind randomized placebo-controlled (RCTs) fixed-dose trials evaluating the use of psilocybin for adult patients with primary or secondary depression. A one-stage dose-response meta-analysis with restricted cubic splines was used. Cochrane risk of bias was used to assess risk of bias. Our analysis included seven studies with a total of 489 participants. Among these, four studies focused on primary depression (N = 366), including one study with patients suffering from treatment-resistant depression. The remaining three studies examined secondary depression (N = 123). The determined 95% effective doses per day (ED95) were 8.92, 24.68, and 36.08 mg/70 kg for patients with secondary depression, primary depression, and both subgroups, respectively. We observed significant dose-response associations for all curves, each plateauing at different levels, except for the bell-shaped curve observed in the case of secondary depression. Additionally, we found significant dose-response associations for various side effects, including physical discomfort, blood pressure increase, nausea/vomiting, headache/migraine, and the risk of prolonged psychosis. In conclusion, we discovered specific ED95 values for different populations, indicating higher ED95 values for treatment-resistant depression, primary depression, and secondary depression groups. Further RCTs are necessary for each population to determine the optimal dosage, allowing for maximum efficacy while minimizing side effects.

Pathogenesis and treatment of depression: Role of diet in prevention and therapy

In recent years, there has been a significant increase in depression, which is related to, among other things, the COVID-19 pandemic. Depression can be fatal if not treated or if treated inappropriately. Depression is the leading cause of suicide attempts. The disease is multifactorial, and pharmacotherapy often fails to bring satisfactory results. Therefore, increasingly more importance is attached to the natural healing substances and nutrients in food, which can significantly affect the therapy process and prevention of depressive disorders. A proper diet is vital to preventing depression and can be a valuable addition to psychological and pharmacologic treatment. An inadequate diet may reduce the effectiveness of antidepressants or increase their side effects, leading to life-threatening symptoms. This study aimed to review the literature on the pathogenesis of the development and treatment of depression, with particular emphasis on dietary supplements and the role of nutrition in the prevention and treatment of depressive disorders.

Research progress of plant-derived natural alkaloids in central nervous system diseases

Central nervous system (CNS) disease is one of the most important causes of human death. Because of their complex pathogenesis, more and more attention has been paid to them. At present, drug treatment of the CNS is the main means; however, most drugs only relieve symptoms, and some have certain toxicity and side effects. Natural compounds derived from plants can provide safer and more effective alternatives. Alkaloids are common nitrogenous basic organic compounds found in nature, which exist widely in many kinds of plants and have unique application value in modern medicine. For example, Galantamine and Huperzine A from medicinal plants are widely used drugs on the market to treat Alzheimer's disease. Therefore, the main purpose of this review is to provide the available information on natural alkaloids with the activity of treating central nervous system diseases in order to explore the trends and perspectives for the further study of central nervous system drugs. In this paper, 120 alkaloids with the potential effect of treating central nervous system diseases are summarized from the aspects of sources, structure types, mechanism of action and structure-activity relationship.

rTMS ameliorates depressive-like behaviors and regulates the gut microbiome and medium- and long-chain fatty acids in mice exposed to chronic unpredictable mild stress

INTRODUCTION

Repetitive transcranial magnetic stimulation (rTMS) is a clinically useful therapy for depression. However, the effects of rTMS on the metabolism of fatty acids (FAs) and the composition of gut microbiota in depression are not well established.

METHODS

Mice received rTMS (15 Hz, 1.26 T) for seven consecutive days after exposure to chronic unpredictable mild stress (CUMS). The subsequent depressive-like behaviors, the composition of gut microbiota of stool samples, as well as medium- and long-chain fatty acids (MLCFAs) in the plasma, prefrontal cortex (PFC), and hippocampus (HPC) were evaluated.

RESULTS

CUMS induced remarkable changes in gut microbiotas and fatty acids, specifically in community diversity of gut microbiotas and PUFAs in the brain. 15 Hz rTMS treatment alleviates depressive-like behaviors and partially normalized CUMS induced alterations of microbiotas and MLCFAs, especially the abundance of Cyanobacteria, Actinobacteriota, and levels of polyunsaturated fatty acids (PUFAs) in the hippocampus and PFC.

CONCLUSION

These findings revealed that the modulation of gut microbiotas and PUFAs metabolism might partly contribute to the antidepressant effect of rTMS.

Effects of Cannabidiol in Adolescent and Young Adult Depressive and Anxiety Disorders: A Systematic Review of Clinical and Preclinical Research

Background

Adolescents and young adults may use cannabidiol (CBD) products in an attempt to reduce depression and anxiety symptoms, despite little research examining this use. This systematic review evaluated preclinical and clinical research on the effects of CBD on depressive and anxiety disorders in adolescence and young adulthood. To provide context, we discuss CBD's mechanism of action and neurodevelopmental effects.

Methods

PubMed was searched for articles published through June 2022. Preclinical or clinical CBD administration studies with N > 1 that examined depressive and/or anxiety disorders were eligible.

Results

Initially, 224 publications were identified. After excluding duplicates and applying eligibility criteria, 6 preclinical (depression: n≈133; anxiety: n≈161) and 4 clinical (anxiety: n=113) articles remained. Due to the low number of studies, results were synthesized qualitatively. The Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence were used to rate each study's evidence. The preclinical effects of CBD on depression-like behavior appear to differ by sex, early life stress, and duration of use. Despite no evidence that CBD exerts anxiolytic effects in preclinical adolescent models, CBD may reduce anxiety symptoms in human adolescents and young adults with anxiety disorders.

Conclusions

The existing evidence suggests that CBD may reduce symptoms of anxiety in adolescents and young adults. However, the evidence is sparse and limited by variations in samples and CBD dosing duration. Further research is needed to understand the potential benefits and/or harms of CBD for depression and anxiety disorders in this population. Implications for clinical practice and research are discussed.

Anxiety disorders in children and adolescents: A summary and overview of the literature

Considerable work has advanced understanding of the nature, causes, management, and prevention of anxiety disorders in children and adolescents over the past 30 years. Prior to this time the primary focus was on school refusal and specific phobias. It is now recognised that children and adolescents experience the full gamut of anxiety disorders in very similar ways to adults and that anxiety disorders in the paediatric years can predict a lifelong mental-health struggle. Given the vast array of specific studies in this field, the current review summarises current knowledge about these high prevalence disorders, points to overarching limitations, and suggests potentially important future directions. Following a brief historical overview, the review summarises knowledge about demographic and epidemiological characteristics, distal and proximal risk factors, current treatment directions, and prevention. There is still a great deal to learn about the causes and treatments of child and adolescent anxiety disorders. By amalgamating our current knowledge, this review provides a window to the research directions that are likely to lead to future advances.

State of the Evidence for Use of Psychotropic Medications in School-Age Youth

Psychotropic medications are commonly prescribed to school-aged youth for the management of mental health concerns. This paper describes the current state of evidence for psychotropic medications in school-aged youth. More specifically, the following sections summarize relevant medication research trials and practice parameters pertaining to psychotropic medication prescribing as well as the specific medications indicated for a range of commonly presenting disorders and symptom clusters in school-aged youth. For each of these disorders and symptom clusters, key findings pertaining to the current state of science and practice are highlighted for the purpose of offering patients, clinicians, researchers, and policymakers with nuanced considerations for the role of psychopharmacology within the context of a larger "whole-child" approach to care that relies on the collaboration of providers and services across systems of care to promote optimal child and family health and wellness. The paper concludes with a discussion about supporting the use of medication treatments in schools, including considerations for ensuring effective family-school-health system collaboration to best meet youth mental health needs.

Systematic Review and Meta-Analysis of the Placebo Effect and its Correlates in Obsessive Compulsive Disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is a major mental health condition with a lifetime prevalence rate of 1.3% among adults. While placebo effects are well described for conditions such as depressive and anxiety disorders, they have not been systematically characterized in OCD.

OBJECTIVES

We aimed to determine the impact of placebos in improving different symptom domains in patients with OCD.

METHODS

We systematically searched PubMed, EMBASE, Scopus, Web of Science, Ovid, the Cochrane Library, and Google Scholar databases/search engine from inception to January 2021 for randomized controlled trials of treatments for OCD with a placebo arm. A modified Cohen's effect size (ES) was calculated using change in baseline to endpoint scores for different measurement scales within placebo arms to estimate placebo effects and to investigate their correlates by random-effects model meta-analyses.

RESULTS

Forty-nine clinical trials (placebo group n  =  1993), reporting 80 OCD specific (153 measures in general) were included in the analysis. Overall placebo ES (95% confidence interval [CI]) was 0.32 (0.22-0.41) on OCD symptoms, with substantial heterogeneity (I-square = 96.1%). Among secondary outcomes, general scales, ES: 0.27 (95%CI: 0.14-0.41), demonstrated higher ES than anxiety and depression scales, ES: 0.14 (95%CI: -0.4 to 0.32) and 0.05 (95%CI: -0.05 to 0.14), respectively. Clinician-rated scales, ES: 0.27(95%CI: 0.20-0.34), had a higher ES than self-reported scales, ES: 0.07 (95%CI: -0.08 to 0.22). More recent publication year, larger placebo group sample size, shorter follow-up duration, and younger age of participants were all associated with larger placebo ES. Egger's test reflected possible small-study effect publication bias (P  =  0.029).

CONCLUSION

Placebo effects are modest in OCD trials and are larger in clinician ratings, for younger patients, and early in the treatment course. These findings underscore the need for clinicians and scientists to be mindful of placebo effects when formulating treatments or research trials for OCD.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42019125979.

Neurobiology of Treatment in Pediatric Anxiety Disorders

Both pharmacologic and psychotherapeutic treatment-related changes increase activity in brain regions implicated in prefrontal regulatory circuits, and the functional connectivity of these regions with the amygdala is enhanced following pharmacological treatment. This may suggest overlapping mechanisms of action across therapeutic modalities. The existing literature is best viewed as a partially constructed scaffold on which to construct a vigorous understanding of biomarkers in pediatric anxiety syndromes. As the field approaches leveraging "fingerprints" in neuroimaging with "outputs" in neuropsychiatric tasks and scale, we can move beyond one-size-fits-all selection of psychiatric interventions toward more nuanced therapeutic strategies that recognize individual differences.

Anxiety and depression: A top-down, bottom-up model of circuit function

A functional interplay of bottom-up and top-down processing allows an individual to appropriately respond to the dynamic environment around them. These processing modalities can be represented as attractor states using a dynamical systems model of the brain. The transition probability to move from one attractor state to another is dependent on the stability, depth, neuromodulatory tone, and tonic changes in plasticity. However, how does the relationship between these states change in disease states, such as anxiety or depression? We describe bottom-up and top-down processing from Marr's computational-algorithmic-implementation perspective to understand depressive and anxious disease states. We illustrate examples of bottom-up processing as basolateral amygdala signaling and projections and top-down processing as medial prefrontal cortex internal signaling and projections. Understanding these internal processing dynamics can help us better model the multifaceted elements of anxiety and depression.

Resistance to Resveratrol Treatment in Experimental PTSD Is Associated with Abnormalities in Hepatic Metabolism of Glucocorticoids

Glucocorticoids are metabolized by the CYP3A isoform of cytochrome P450 and by 11-β-hydroxysteroid dehydrogenase type 1 (11β-HSD-1). Experimental data suggest that post-traumatic stress disorder (PTSD) is associated with an increase in hepatic 11β-HSD-1 activity and a concomitant decrease in hepatic CYP3A activity. Trans-resveratrol, a natural polyphenol, has been extensively studied for its antipsychiatric properties. Recently, protective effects of trans-resveratrol were found in relation to PTSD. Treatment of PTSD rats with trans-resveratrol allowed the rats to be divided into two phenotypes. The first phenotype is treatment-sensitive rats (TSR), and the second phenotype is treatment-resistant rats (TRRs). In TSR rats, trans-resveratrol ameliorated anxiety-like behavior and reversed plasma corticosterone concentration abnormalities. In contrast, in TRR rats, trans-resveratrol aggravated anxiety-like behavior and decreased plasma corticosterone concentration. In TSR rats, hepatic 11β-HSD-1 activity was suppressed, with a concomitant increase in CYP3A activity. In TRR rats, the activities of both enzymes were suppressed. Thus, the resistance of PTSD rats to trans-resveratrol treatment is associated with abnormalities in hepatic metabolism of glucocorticoids. The free energy of binding of resveratrol, cortisol, and corticosterone to the human CYP3A protein was determined using the molecular mechanics Poisson-Boltzmann surface area approach, indicating that resveratrol could affect CYP3A activity.

Need for Multidimensional and Multidisciplinary Management of Depressed Preadolescents and Adolescents: A Review of Randomized Controlled Trials on Oral Supplementations (Omega-3, Fish Oil, Vitamin D3)

(1) Background: Depression is a serious health problem with a high cost for public administration. Epidemiological studies report that one in five children have a mental disorder and about 50% of mental health problems exacerbate in childhood and adolescence. Moreover, the antidepressant efficacy in children and adolescents is poorly demonstrated and can cause severe behavioral adverse events such as suicidal ideation. (2) Methods: This systematic literature review examined oral supplementations (Omega-3, fish oil, Vitamin D₃) to treat depressed children, preadolescents, and adolescents. MEDLINE, Scopus, Embase, and PsycInfo were searched for articles published in the last five years. Six studies met the eligibility criteria. The inclusion criteria encompassed children, preadolescents, and adolescents, a diagnosis of depression, and an intervention of oral supplementations such as Omega-3, fish oil, and Vitamin D₃. (3) Results: Most of the studies demonstrated that dietary intervention provides positive outcomes in terms of depression symptoms. (4) Conclusions: Overall, the results demonstrate a positive effect for oral supplementation suggesting an increase intake of Omega-3, fish oil, and Vitamin D₃. However, only a few studies assess the effectiveness of diet recommendations, as a monotherapy or combined treatment, for the management of depression at developmental ages. Thus, there is still a need to further investigate these aspects and to look more specifically at adolescents and preadolescents.

Anxiety and Depression Treatment in Primary Care Pediatrics

BACKGROUND AND OBJECTIVES

Primary care pediatricians (PCP) are often called on to manage child and adolescent anxiety and depression. The objective of this study was to describe PCP care practices around prescription of selective serotonin reuptake inhibitors (SSRI) for patients with anxiety and/or depression by using medical record review.

METHODS

We identified 1685 patients who had at least 1 visit with a diagnosis of anxiety and/or depression in a large primary care network and were prescribed an SSRI by a network PCP. We randomly selected 110 for chart review. We reviewed the visit when the SSRI was first prescribed (medication visit), immediately previous visit, and immediately subsequent visit. We abstracted rationale for prescribing medication, subspecialist involvement, referral for psychotherapy, and medication monitoring practices.

RESULTS

At the medication visit, in 82% (n = 90) of cases, PCPs documented reasons for starting an SSRI, most commonly clinical change (57%, n = 63). Thirty percent (n = 33) of patients had documented involvement of developmental-behavioral pediatrics or psychiatry subspecialists at 1 of the 3 visits reviewed. Thirty-three percent (n = 37) were referred to unspecified psychotherapy; 4% (n = 4) were referred specifically for cognitive behavioral therapy. Of 69 patients with a subsequent visit, 48% (n = 33) had documentation of monitoring for side effects.

CONCLUSIONS

When prescribing SSRIs for children with anxiety and/or depression, PCPs in this network documented appropriate indications for starting medication and prescribed without subspecialist involvement. Continuing medical education for PCPs who care for children with these conditions should include information about evidence-based psychotherapy and strategies for monitoring potential side effects.

Electroacupuncture alleviated depression‐like behaviors in ventromedial prefrontal cortex of chronic unpredictable mild stress‐induced rats: Increasing synaptic transmission and phosphorylating dopamine transporter

AIMS

Electroacupuncture (EA) shows advantages in both clinical practice and depression animal models. Dopaminergic-related dysfunction in the prefrontal cortex (PFC) may be a hidden antidepressant mechanism of EA, where dopamine transporter (DAT) plays an essential role. This study aimed to investigate the synaptic transmission and DAT-related changes of EA in depression.

METHODS

Male Sprague-Dawley rats were subjected to 3-week chronic unpredictable mild stress (CUMS). The successfully modeled rats were then randomly and equally assigned to CUMS, selective serotonin reuptake inhibitor (SSRI), and EA or SSRI + EA groups, followed by a 2-week treatment respectively. After monitoring body weight and behavioral tests of all rats, the ventromedial PFC (vmPFC) tissue was collected for electrophysiology and the expression detection of DAT, phosphorylated DAT (p-DAT), cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), and trace amine-associated receptor 1 (TAAR1).

RESULTS

Depressive-like behaviors induced by CUMS were alleviated by EA, SSRI, and SSRI + EA treatments through behavioral tests. Compared with CUMS group, EA improved synaptic transmission in vmPFC by upregulating spontaneous excitatory postsynaptic currents amplitude. Molecularly, EA reversed the increased total DAT and p-DAT expression as well as the decreased ratio of p-DAT/total DAT along with the activation of TAAR1, cAMP, and PKA in vmPFC.

CONCLUSION

We speculated that the antidepressant effect of EA was associated with enhanced synaptic transmission in vmPFC, and the upregulated phosphorylation of DAT relevant to TAAR1, cAMP, and PKA may be the potential mechanism.