Increased BDNF levels after electroconvulsive therapy in patients with major depressive disorder: A meta-analysis study

Perspectives in treatment-resistant depression: esketamine and electroconvulsive therapy

Modern electroconvulsive therapy (ECT) and the approval of nasal esketamine for clinical use have significantly improved the approach to treatment-resistant depression (TRD), which is defined as non-response to at least two different courses of antidepressants with verified adherence to treatment, adequate dosage, and duration of treatment. The goal of this literature review is to present the newest evidence regarding efficacy and safety. Furthermore, we aim to provide an overview of future perspectives in this field of research, for example, regarding structural and molecular effects. Both treatment methods will be critically evaluated for their individual advantages, disadvantages, and response rates. Firstly, we will discuss the well-established method of ECT and its different treatment modalities. Secondly, we will discuss the properties of ketamine, the discovery of its antidepressive effects and the route to clinical approval of the esketamine nasal spray. We will comment on research settings which have evaluated intravenous ketamine against ECT. The decision-making process between esketamine nasal spray or ECT should include the assessment of contraindications, age, severity of disease, presence of psychotic symptoms, patient preference and treatment accessibility. We conclude that both treatment options are highly effective in TRD. If both are indicated, pragmatically esketamine will be chosen before ECT; however, ECT studies in ketamine non-responders are missing.

Altered in vivo early neurogenesis traits in patients with depression: Evidence from neuron-derived extracellular vesicles and electroconvulsive therapy

BACKGROUND

The neurogenesis hypothesis is a promising candidate etiologic hypothesis for depression, and it is associated with electroconvulsive therapy (ECT). However, human in vivo molecular-level evidence is lacking.

OBJECTIVE

We used neuron-derived extracellular vesicles (NDEVs) as a "window to the neurons" to explore the in vivo neurogenesis status associated with ECT in patients with treatment-resistant depression (TRD).

METHODS

In this study, we enrolled 40 patients with TRD and 35 healthy controls (HCs). We isolated NDEVs from the plasma of each participant to test the levels of doublecortin (DCX), a marker of neurogenesis, and cluster of differentiation (CD) 81, a marker of EVs. We also assessed the plasma levels of brain-derived neurotrophic factor (BDNF), a protein that is known to be associated with ECT and neuroplastic processes.

RESULTS

Our findings indicated that both the levels of DCX in NDEVs and BDNF in plasma were significantly lower in TRD patients compared to HCs at baseline, but increased following ECTs. Conversely, levels of CD81 in NDEVs were found higher in TRD patients at baseline, but did not change after the ECT treatments. Exploratory analyses revealed that lower levels of BDNF in plasma and DCX in NDEVs, along with higher CD81 levels in NDEVs, were associated with more severe depressive symptoms and reduced cognitive function at baseline. Furthermore, higher baseline CD81 concentrations in NDEVs were correlated with greater decreases in depression symptoms.

CONCLUSIONS

We first present human in vivo evidence of early neurogenesis using DCX through NDEVs: decreased in TRD patients, increased after ECTs.

Functional connectivity changes between amygdala and prefrontal cortex after ECT are associated with improvement in distinct depressive symptoms

Electroconvulsive therapy (ECT) is one of the most effective treatments for treatment-resistant depression. However, the underlying mechanisms of action are not yet fully understood. The investigation of depression-specific networks using resting-state fMRI and the relation to differential symptom improvement might be an innovative approach providing new insights into the underlying processes. In this naturalistic study, we investigated the relationship between changes in resting-state functional connectivity (rsFC) and symptom improvement after ECT in 21 patients with treatment-resistant depression. We investigated rsFC before and after ECT and focused our analyses on FC changes directly related to symptom reduction and on FC at baseline to identify neural targets that might predict individual clinical responses to ECT. Additional analyses were performed to identify the direct relationship between rsFC change and symptom dimensions such as sadness, negative thoughts, detachment, and neurovegetative symptoms. An increase in rsFC between the left amygdala and left dorsolateral prefrontal cortex (DLPFC) after ECT was related to overall symptom reduction (Bonferroni-corrected p = 0.033) as well as to a reduction in specific symptoms such as sadness (r = 0.524, uncorrected p = 0.014), negative thoughts (r = 0.700, Bonferroni-corrected p = 0.002) and detachment (r = 0.663, p = 0.004), but not in neurovegetative symptoms. Furthermore, high baseline rsFC between the left amygdala and the right frontal pole (FP) predicted treatment outcome (uncorrected p = 0.039). We conclude that changes in FC in regions of the limbic-prefrontal network are associated with symptom improvement, particularly in affective and cognitive dimensions. Frontal-limbic connectivity has the potential to predict symptom improvement after ECT. Further research combining functional imaging biomarkers and a symptom-based approach might be promising.

Associations of BDNF/BDNF-AS SNPs with Depression, Schizophrenia, and Bipolar Disorder

Brain-Derived Neurotrophic Factor (BDNF) is crucial for various aspects of neuronal development and function, including synaptic plasticity, neurotransmitter release, and supporting neuronal differentiation, growth, and survival. It is involved in the formation and preservation of dopaminergic, serotonergic, GABAergic, and cholinergic neurons, facilitating efficient stimulus transmission within the synaptic system and contributing to learning, memory, and overall cognition. Furthermore, BDNF demonstrates involvement in neuroinflammation and showcases neuroprotective effects. In contrast, BDNF antisense RNA (BDNF-AS) is linked to the regulation and control of BDNF, facilitating its suppression and contributing to neurotoxicity, apoptosis, and decreased cell viability. This review article aims to comprehensively overview the significance of single nucleotide polymorphisms (SNPs) in BDNF/BDNF-AS genes within psychiatric conditions, with a specific focus on their associations with depression, schizophrenia, and bipolar disorder. The independent influence of each BDNF/BDNF-AS gene variation, as well as the interplay between SNPs and their linkage disequilibrium, environmental factors, including early-life experiences, and interactions with other genes, lead to alterations in brain architecture and function, shaping vulnerability to mental health disorders. The potential translational applications of BDNF/BDNF-AS polymorphism knowledge can revolutionize personalized medicine, predict disease susceptibility, treatment outcomes, and guide the selection of interventions tailored to individual patients.

Epigenetic neural glioblastoma enhances synaptic integration and predicts therapeutic vulnerability

Neural-tumor interactions drive glioma growth as evidenced in preclinical models, but clinical validation is nascent. We present an epigenetically defined neural signature of glioblastoma that independently affects patients' survival. We use reference signatures of neural cells to deconvolve tumor DNA and classify samples into low- or high-neural tumors. High-neural glioblastomas exhibit hypomethylated CpG sites and upregulation of genes associated with synaptic integration. Single-cell transcriptomic analysis reveals high abundance of stem cell-like malignant cells classified as oligodendrocyte precursor and neural precursor cell-like in high-neural glioblastoma. High-neural glioblastoma cells engender neuron-to-glioma synapse formation in vitro and in vivo and show an unfavorable survival after xenografting. In patients, a high-neural signature associates with decreased survival as well as increased functional connectivity and can be detected via DNA analytes and brain-derived neurotrophic factor in plasma. Our study presents an epigenetically defined malignant neural signature in high-grade gliomas that is prognostically relevant.

Magnetic Waves vs. Electric Shocks: A Non-Inferiority Study of Magnetic Seizure Therapy and Electroconvulsive Therapy in Treatment-Resistant Depression

Treatment-resistant depression (TRD), characterized by the failure to achieve symptomatic remission despite multiple pharmacotherapeutic treatments, poses a significant challenge for clinicians. Electroconvulsive therapy (ECT) is an effective but limited option due to its cognitive side effects. In this context, magnetic seizure therapy (MST) has emerged as a promising alternative, offering comparable antidepressant efficacy with better cognitive outcomes. However, the clinical outcomes and cognitive effects of MST require further investigation. This double-blinded, randomized, non-inferiority study aims to compare the efficacy, tolerability, cognitive adverse effects, and neurophysiological biomarkers of MST with bilateral ECT (BT ECT) in patients with TRD. This study will employ multimodal nuclear magnetic resonance imaging (MRI) and serum neurotrophic markers to gain insight into the neurobiological basis of seizure therapy. Additionally, neurophysiological biomarkers will be evaluated as secondary outcomes to predict the antidepressant and cognitive effects of both techniques. The study design, recruitment methods, ethical considerations, eligibility criteria, interventions, and blinding procedures are described. The expected outcomes will advance the field by offering a potential alternative to ECT with improved cognitive outcomes and a better understanding of the underlying pathophysiology of depression and antidepressant therapies.

[Practice of anaesthesia for electroconvulsive therapy]

Electroconvulsive therapy (ECT) is an established therapeutic method for the treatment of severe mental disorders refractory to pharmaco- and psychotherapy. ECT is a first-line treatment option in delusional disorders, severe depression with acute suicidal tendency or life-threatening catatonia. Usually, ECT is performed as a treatment series. Under short-term anaesthesia and muscle relaxation, tonic-clonic seizures are induced using an external stimulation electrode. Convulsion can be exerted by uni- or bipolar stimulation using an electric charge up to 1000 millicoulomb (mC) with an amperage of 900 mA. Muscular relaxation is necessary to prevent injuries caused by uncontrolled movements during convulsion. During paralysis, consciousness is blocked by general anaesthesia, although ECT is associated with antegrade amnesia for seizure induction and the seizure itself. In the context of ECT, the ideal hypnotic should be characterised by rapid onset, short duration of action and negligible anticonvulsive effects (i.e., least possible impact on seizure quality and duration). As mutual awareness of psychiatric and anaesthesiologic techniques is essential for safe and effective conduction of ECT, this article presents ECT both from the psychiatrist's and the anaesthesiologist's perspective.

The Role of Psychotherapy in the Management of Treatment-Resistant Depression

This article reviews the role of psychotherapy in management of treatment-resistant depression (TRD). Meta-analyses of randomized trials show that psychotherapy has a positive therapeutic benefit in TRD. There is less evidence that one type of psychotherapy approach is superior to another. However, more trials have examined cognitive-based therapies than other forms of psychotherapy. Also reviewed is the potential combination of psychotherapy modalities and medication/somatic therapies as an approach to TRD. There is significant interest in ways that psychotherapy modalities could be combined with medication/somatic therapies to harness a state of enhanced neural plasticity and improve longer-term outcomes in mood disorders.

Brain-derived neurotrophic factor blood levels after electroconvulsive therapy in patients with mental disorders: A systematic review and meta-analysis

OBJECTIVE

Multiple studies have indicated that electroconvulsive therapy (ECT) could increase brain-derived neurotrophic factor (BDNF) concentrations in patients with different mental disorders. The aim of this synthesis was to evaluate post-ECT BDNF concentrations in patients with various mental disorders.

METHODS

The Embase, PubMed and Web of Science databases were systematically searched for studies in English comparing BDNF concentrations before and after ECT through 11/2022. We extracted the pertinent information from the included studies and evaluated their quality. The standardized mean difference (SMD) with a 95% confidence interval (CI) was calculated to quantify BDNF concentration differences.

RESULTS

In total, 35 studies assessed BDNF concentrations in 868 and 859 patients pre and post-ECT treatment, respectively. Post-ECT-treatment BDNF concentrations were significantly higher than the pretreatment concentrations (Hedges'g = -0.50, 95% CI (-0.70, -0.30), heterogeneity I² = 74%, p < 0.001). The analysis that combined both ECT responders and non-responders demonstrated a marked increase in total BDNF levels subsequent to ECT treatment (Hedges'g = -0.27, 95% CI (-0.42, -0.11), heterogeneity I² = 40%, p = 0.0007).

CONCLUSION

Irrespective of the effectiveness of ECT, Our study shows that peripheral BDNF concentrations increase significantly after the entire course of ECT, which may enhance our comprehension of the interplay between ECT treatment and BDNF levels. However, BDNF concentrations were not associated with the effectiveness of ECT, and abnormal concentrations of BDNF may be linked to the pathophysiological process of mental illness, necessitating more future research.

Clinical Improvement in Depression and Cognitive Deficit Following Electroconvulsive Therapy

Electroconvulsive therapy (ECT) is a long-standing treatment choice for disorders such as depression when pharmacological treatments have failed. However, a major drawback of ECT is its cognitive side effects. While numerous studies have investigated the therapeutic effects of ECT and its mechanism, much less research has been conducted regarding the mechanism behind the cognitive side effects of ECT. As both clinical remission and cognitive deficits occur after ECT, it is possible that both may share a common mechanism. This review highlights studies related to ECT as well as those investigating the mechanism of its outcomes. The process underlying these effects may lie within BDNF and NMDA signaling. Edema in the astrocytes may also be responsible for the adverse cognitive effects and is mediated by metabotropic glutamate receptor 5 and the protein Homer1a.

The role of BDNF in major depressive disorder, related clinical features, and antidepressant treatment: insight from meta-analyses

The brain-derived neurotrophic factor (BDNF) has received considerable attention as a potential biomarker of major depressive disorder (MDD) and antidepressant response. We conducted an overview of meta-analyses investigating the relationship of BDNF with MDD, related clinical features, and antidepressant treatment. Based on a systematic screening on main electronic databases, 11 systematic reviews with meta-analyses were included. Available evidence suggests that people with MDD have peripheral and central BDNF levels lower than non-depressed individuals. A negative correlation between blood BDNF and symptom severity emerged, while no association with suicidality was detected. Moreover, an increase in blood BDNF levels after antidepressant treatment, proportional to symptom improvement, was reported. BDNF levels seem to be increased in both treatment responders and remitters, remaining stable in non-responders. Conversely, no variations of BDNF concentrations after non-pharmacological interventions (electroconvulsive therapy, repetitive transcranial magnetic stimulation, and physical activity) were found. The findings of this overview appear consistent with the neurotrophic hypothesis of depression, suggesting that BDNF may play a role in both MDD pathophysiology and pharmacological treatment response.

Electroconvulsive therapy for treatment-resistant depression

Electroconvulsive therapy (ECT), the oldest brain stimulation procedure in psychiatry, is associated with rapid response and remission in majority of patients with resistant, severe, and sometimes life-threatening depression. ECT has been included as an essential component in the definition of treatment-resistant depression (TRD) to display the course and diversification of TRD. On the other hand, ECT remains the treatment of choice for the most severe incapacitating forms of TRD and is a cost-effective treatment. In this chapter, we reviewed some essential studies, meta-analysis, and expert guidelines regarding ECT in TRD. ECT should not be considered as a treatment of last resort, and its administration should be considered on the basis of individual patient and illness factors. The clinical role of ECT vs other neurostimulation treatments for TRD, that is, repetitive transcranial magnetic stimulation, were also explored. Much effort has been directed toward the clinical and basic research about mechanisms of action of ECT in depression. A thorough understanding of the neurobiological effects of ECT may increase our understanding of its therapeutic effects, ultimately leading to improved patient care. We also showed that the distinct mechanisms of ECT in biological treatments of major depressive disorder (MDD) and some recent approaches to understand this most common psychiatric disorder. ECT should remain a standard part of modern psychiatric medicine. We recommend a more careful and thoughtful application of this traditional but effective technology.

Effects of Transcranial Pulse Stimulation (TPS) on Adults with Symptoms of Depression-A Pilot Randomized Controlled Trial

Transcranial pulse stimulation (TPS) is a recent development in non-invasive brain stimulations (NIBS) that has been proven to be effective in terms of significantly improving Alzheimer patients' cognition, memory, and execution functions. Nonetheless, there is, currently, no trial evaluating the efficacy of TPS on adults with major depression disorder (MDD) nationwide. In this single-blinded, randomized controlled trial, a 2-week TPS treatment comprising six 30 min TPS sessions were administered to participants. Participants were randomized into either the TPS group or the Waitlist Control (WC) group, stratified by gender and age according to a 1:1 ratio. Our primary outcome was evaluated by the Hamilton depression rating scale-17 (HDRS-17). We recruited 30 participants that were aged between 18 and 54 years, predominantly female (73%), and ethnic Chinese from 1 August to 31 October 2021. Moreover, there was a significant group x time interaction (F(1, 28) = 18.8, p < 0.001). Further, when compared with the WC group, there was a significant reduction in the depressive symptom severity in the TPS group (mean difference = -6.60, p = 0.02, and Cohen's d = -0.93). The results showed a significant intervention effect; in addition, the effect was large and sustainable at the 3-month follow-up. In this trial, it was found that TPS is effective in reducing depressive symptoms among adults with MDD.

BDNF blood levels after electroconvulsive therapy in patients with mood disorders: An updated systematic review and meta-analysis

OBJECTIVES

Studies have suggested Brain-Derived Neurotrophic Factors (BDNF) increase after electroconvulsive therapy (ECT) although they were methodologically limited and enrolled small sample sizes. We aimed at updating a systematic review and meta-analysis to explore BDNF changes after ECT for the treatment of depression.

METHODS

PubMed, PsycInfo, Embase and Global health were searched (March, 2021). Clinical trials that measured BDNF in the blood before and after ECT in adults (≥ 18 years old) with depression (major depressive disorder or bipolar disorder) were eligible. Data were pooled through random-effects meta-analyses.

RESULTS

Twenty-eight studies involving 778 participants were included. Meta-analysis showed a significant increase in BDNF levels after ECT (Hedges' g = 0.28; 95% CI: 0.10, 0.46) while there was evidence of significant heterogeneity (I² = 67.64%) but not publication bias/small-study effect. Subgroup analyses and meta-regressions were underpowered to detect significant differences. Meta-analysis of depression severity scores demonstrated a considerable larger treatment effect in reducing depressive symptoms after ECT (Hedge's g = -3.72 95% CI: -4.23, -3.21).

CONCLUSION

This updated review showed that BDNF blood levels increased after ECT treatment. However, there was still evidence of substantial heterogeneity and there were limited sample sizes to investigate factors driving the variability of effects across studies. Importantly, the increase in BDNF levels was substantially smaller than the observed in depressive symptomatology, which could be indicative that the former was independent than the latter. Additional studies with larger sample sizes are currently required.

The efficacy and safety of esketamine in the treatment of major depressive disorder with suicidal ideation: study protocol for a randomized controlled trial

BACKGROUND

Major depressive disorder (MDD) is a high risk factor for suicide, with up to 20% of MDD patients attempting suicide during their lifetime. Current treatments for MDD are slow onset of action, low efficiency, and the inability to control suicidal behaviors quickly and effectively. Intravenous ketamine has been shown to have a rapid but transient antidepressant effect, but there is still lack evidence on the efficacy and safety of intravenous esketamine in reducing suicidal ideation and depressive symptoms in MDD patients with suicidal ideation. We designed a study to investigate the effect of short-term repeated intravenous infusion of esketamine three times in MDD patients with suicidal ideation.

METHODS

This study features a randomized, double-blind, placebo-controlled trial (RCT) comparing short-term repeated intravenous infusions of esketamine with placebo as a supplement to conventional antidepressants with an intervention period of 6 days and one infusion every other day, followed by 4 weeks of follow-up. These methods support the examination of the efficacy, safety, tolerability, and mechanism of action of short-term repeated intravenous infusions of esketamine in MDD patients with suicidal ideation.

DISCUSSION

This is the first RCT to explore the efficacy and safety of short-term repeated infusion of esketamine on suicidal ideation and depressive symptoms in MDD patients with suicidal ideation. If proven effective and tolerated, it will provide evidence for rapid and effective treatment of suicidal ideation and depressive symptoms in MDD individuals with suicidal ideation.

TRIAL REGISTRATION

Chinese Clinical Trial Register, ChiCTR2000041232 . Registered 22 December 2020.

BDNF receptor TrkB as the mediator of the antidepressant drug action

Brain-derived neurotrophic factor (BDNF) signaling through its receptor TrkB has for a long time been recognized as a critical mediator of the antidepressant drug action, but BDNF signaling has been considered to be activated indirectly through the action of typical and rapid-acting antidepressants through monoamine transporters and glutamate NMDA receptors, respectively. However, recent findings demonstrate that both typical and the fast-acting antidepressants directly bind to TrkB and thereby allosterically potentiate BDNF signaling, suggesting that TrkB is the direct target for antidepressant drugs. Increased TrkB signaling particularly in the parvalbumin-expressing interneurons orchestrates iPlasticity, a state of juvenile-like enhanced plasticity in the adult brain. iPlasticity sensitizes neuronal networks to environmental influences, enabling rewiring of networks miswired by adverse experiences. These findings have dramatically changed the position of TrkB in the antidepressant effects and they propose a new end-to-end model of the antidepressant drug action. This model emphasizes the enabling role of antidepressant treatment and the active participation of the patient in the process of recovery from mood disorders.

Brain-Derived Neurotrophic Factor (BDNF) as a biomarker of treatment response in patients with Treatment Resistant Depression (TRD): A systematic review & meta-analysis

Multiple lines of evidence have implicated brain-derived neurotrophic factor (BDNF) in treatment-resistant depression (TRD). The aim of this synthesis was to determine the impact of TRD treatments on peripheral BDNF levels, and ascertain whether these changes are associated with antidepressant effects. Thirty-six articles involving 1198 patients with TRD were included herein. Electroconvulsive therapy (ECT), ketamine, and repetitive transcranial magnetic stimulation (rTMS) were the most common TRD treatments investigated. Serum BDNF levels significantly increased in six, two, four and one studies following ECT, ketamine, rTMS and atypical antipsychotics, respectively. The estimated mean baseline serum BDNF concentration in TRD patients ± 95% CI was 15.5 ± 4.34 ng/mL. Peripheral BDNF levels significantly increased overall (Hedges' g ± 95% CI = 0.336 ± 0.302; p < 0.05), but no association with depressive symptoms was found (p ≥ 0.05). These results demonstrate that peripheral measurements of total BDNF (i.e., mature and percursor forms of BDNF) are inadequate predictors of treatment response in TRD patients, and other considerations suggest that this would still apply to separable measurements of mature BDNF and its precursor.

Association between plasma levels of BDNF and GDNF and the diagnosis, treatment response in first-episode MDD

INTRODUCTION

The aims of our study are: i) to explore whether plasma levels of BDNF/GDNF are valuable in the diagnosis of first-episode depression; ii) to discuss whether there is an association between peripheral plasma levels of BDNF/GDNF and patients' depression severity and cognitive dysfunction; iii) to explore the association between plasma levels of BDNF/GDNF and the effectiveness of antidepressant treatment.

METHODS

Ninety patients with first-episode unmedicated MDD and healthy controls were recruited. MDD patients were treated with antidepressant medication for 8 weeks. Patients were assessed for clinical symptoms using HDRS-17 and HAMA-14. Social and neurocognitive functioning of all subjects was assessed at baseline using the Functional Assessment Test Short Form (FAST) and the MATRICS Consensus Cognitive Battery (MCCB). At the same time, peripheral venous blood was drawn from all subjects for BDNF/GDNF peripheral plasma level analysis at baseline and after 8 weeks of treatment.

RESULTS

The baseline BDNF/GDNF levels in MDD patients were significantly lower than that in healthy controls. The area under ROC curve (AUC) of baseline plasma BDNF and GDNF levels predicting MDD was 0.776 (95 % CI: 0.705-0.846, p < 0.001) and 0.864 (95 % CI: 0.808-0.920, p < 0.001), respectively. The baseline GDNF level (beta = 0.425, p = 0.001), the autonomy score of FAST (beta = -0.247, p = 0.037) and BACS-SC score of MCCB (beta = 0.323, p = 0.039) were predictors of HDRS-17 reduction rate after 8 weeks' antidepressant treatment.

LIMITATIONS

A longer follow-up period than 8 weeks may make the results more convincing, and the sample size of this study is still insufficient.

CONCLUSION

The decreased plasma levels of BDNF and GDNF are strong indicators for predicting the occurrence of MDD. This preliminary finding highlighted the value of GDNF plasma concentrations in the diagnosis of MDD and the prognosis of antidepressant treatment.

Longitudinal alterations in mRNA expression of the BDNF neurotrophin signaling cascade in blood correlate with changes in depression scores in patients undergoing electroconvulsive therapy

Electroconvulsive therapy (ECT) appears to be the most effective treatment for severe depression. However, its mechanisms of action are incompletely understood. Evidence suggests ECT enhances neuroplasticity and neurogenesis. While studies on ECT-induced neuroplasticity focused on brain-derived neurotrophic factor (BDNF), other factors of the BDNF/TrkB signaling cascade remain underinvestigated. We assessed longitudinal changes in depression scores, serum BDNF protein levels, and mRNA expression of BDNF/TrkB related genes (BDNF, AKT1, ERK1, CREB), NR3C1 and IGF1 in peripheral blood in 19 treatment-resistant depressed patients undergoing ECT. We also analysed DNA methylation patterns at various timepoints to explore possible epigenetic regulation of mRNA expression. Using multilevel regression, we found a negative association between depression scores and blood-based mRNA expression of BDNF/TrkB related genes and NR3C1. Expression of BDNF, ERK1 and NR3C1 increased significantly over time (BDNF: β = 0.0295, p = 0.003; ERK1: β = 0.0170, p = 0.034; NR3C1: β = 0.0035, p = 0.050). For these three genes changes in mRNA expression were highly correlated (R = 0.59 - 0.88) with changes in DNA methylation for multiple CpG sites in the respective genes. Also, serum BDNF protein levels increased across the study period (β = 0.11, p = 0.001). Our findings show that the antidepressant effects of ECT are associated with changes in expression of BDNF and its signaling molecules and that these molecular markers can be detected in peripheral blood. Alterations in DNA methylation could be a key mechanism whereby ECT influences gene expression.

Noise Induced Depression-Like Behavior, Neuroinflammation and Synaptic Plasticity Impairments: The Protective Effects of Luteolin

Noise is a kind of sound that causes agitation and harms human health. Studies have shown that noise can lead to neuroinflammation, damage to synaptic plasticity and altered levels of neurotransmitters that may result in depression. The present study demonstrated that luteolin exerted antidepressant-like effects by improving neuroinflammation in a mouse model of noise-induced depression. Luteolin significantly alleviated noise-induced depression-like behavior. Notably, luteolin treatment not only remarkably ameliorated noise-induced inflammation in the hippocampus and prefrontal cortex, but also increased synapsin. Furthermore, luteolin treatment significantly increased the contents of serum 5-hydroxytryptamine and norepinephrine in noise-induced mice. In sum, luteolin exerts antidepressant effects indepression-like mice caused by noise, which can serve as a potential agent for the treatment of chronic noise-induced depression.

Electroconvulsive Therapy in Psychiatric Disorders: A Narrative Review Exploring Neuroendocrine–Immune Therapeutic Mechanisms and Clinical Implications

Electroconvulsive therapy (ECT) is based on conducting an electrical current through the brain to stimulate it and trigger generalized convulsion activity with therapeutic ends. Due to the efficient use of ECT during the last years, interest in the molecular bases involved in its mechanism of action has increased. Therefore, different hypotheses have emerged. In this context, the goal of this review is to describe the neurobiological, endocrine, and immune mechanisms involved in ECT and to detail its clinical efficacy in different psychiatric pathologies. This is a narrative review in which an extensive literature search was performed on the Scopus, Embase, PubMed, ISI Web of Science, and Google Scholar databases from inception to February 2022. The terms “electroconvulsive therapy”, “neurobiological effects of electroconvulsive therapy”, “molecular mechanisms in electroconvulsive therapy”, and “psychiatric disorders” were among the keywords used in the search. The mechanisms of action of ECT include neurobiological function modifications and endocrine and immune changes that take place after ECT. Among these, the decrease in neural network hyperconnectivity, neuroinflammation reduction, neurogenesis promotion, modulation of different monoaminergic systems, and hypothalamus–hypophysis–adrenal and hypothalamus–hypophysis–thyroid axes normalization have been described. The majority of these elements are physiopathological components and therapeutic targets in different mental illnesses. Likewise, the use of ECT has recently expanded, with evidence of its use for other pathologies, such as Parkinson’s disease psychosis, malignant neuroleptic syndrome, post-traumatic stress disorder, and obsessive–compulsive disorder. In conclusion, there is sufficient evidence to support the efficacy of ECT in the treatment of different psychiatric disorders, potentially through immune, endocrine, and neurobiological systems.

Rapid treatments for depression: Endocannabinoid system as a therapeutic target

Current first-line treatments for major depressive disorder (MDD), i.e., antidepressant drugs and psychotherapy, show delayed onset of therapeutic effect as late as 2-3 weeks or more. In the clinic, the speed of beginning of the actions of antidepressant drugs or other interventions is vital for many reasons. Late-onset means that depression, its related disability, and the potential danger of suicide remain a threat for some patients. There are some rapid-acting antidepressant interventions, such as sleep deprivation, ketamine, acute exercise, which induce a significant response, ranging from a few hours to maximally one week, and most of them share a common characteristic that is the activation of the endocannabinoid (eCB) system. Activation of this system, i.e., augmentation of eCB signaling, appears to have anti-depressant-like actions. This article puts the idea forward that the activation of eCB signaling represents a critical mechanism of rapid-acting therapeutic interventions in MDD, and this system might contribute to the development of novel rapid-acting treatments for MDD.

Structural and Functional MRI Brain Changes in Patients with Schizophrenia Following Electroconvulsive Therapy: A Systematic Review

BACKGROUND

Schizophrenia (SZ) is a severe psychiatric disorder typically characterized by multidimensional psychotic syndromes. Electroconvulsive therapy (ECT) is a treatment option for medication-resistant patients with SZ or treating acute symptoms. Although the efficacy of ECT has been demonstrated in clinical use, its therapeutic mechanisms in the brain remain elusive.

OBJECTIVE

This study aimed to summarize brain changes on structural magnetic resonance imaging (sMRI) and functional MRI (fMRI) after ECT.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was carried out. The PubMed and Medline databases were systematically searched using the following medical subject headings (MeSH): (electroconvulsive therapy OR ECT) AND (schizophrenia) AND (MRI OR fMRI OR DTI OR DWI).

RESULTS

This review yielded 12 MRI studies, including 4 with sMRI, 5 with fMRI and 3 with multimodal MRI. Increases in volumes of the hippocampus and its adjacent regions (parahippocampal gyrus and amygdala), as well as the insula and frontotemporal regions, were noted after ECT. fMRI studies found ECT-induced changes in different brain regions/networks, including the hippocampus, amygdala, default model network, salience network and other regions/networks that are thought to highly correlate with the pathophysiologic characteristics of SZ. The results of the correlation between brain changes and symptom remissions are inconsistent.

CONCLUSION

Our review provides evidence supporting ECT-induced brain changes on sMRI and fMRI in SZ and explores the relationship between these changes and symptom remission.

Effects of Transcranial Pulse Stimulation (TPS) on Young Adults With Symptom of Depression: A Pilot Randomised Controlled Trial Protocol

Background

Since the emergence of the COVID-19 pandemic, there have been lots of published work examining the association between COVID-19 and mental health, particularly, anxiety and depression in the general populations and disease subpopulations globally. Depression is a debilitating disorder affecting individuals' level of bio-psychological-social functioning across different age groups. Since almost all studies were cross-sectional studies, there seems to be a lack of robust, large-scale, and technological-based interventional studies to restore the general public's optimal psychosocial wellbeing amidst the COVID-19 pandemic. Transcranial pulse stimulation (TPS) is a relatively new non-intrusive brain stimulation (NIBS) technology, and only a paucity of studies was conducted related to the TPS treatment on older adults with mild neurocognitive disorders. However, there is by far no study conducted on young adults with major depressive disorder nationwide. This gives us the impetus to execute the first nationwide study evaluating the efficacy of TPS on the treatment of depression among young adults in Hong Kong.

Methods

This study proposes a two-armed single-blinded randomised controlled trial including TPS as an intervention group and a waitlist control group. Both groups will be measured at baseline (T1), immediately after the intervention (T2), and at the 3- month follow-up (T3).

Recruitment

A total of 30 community-dwelling subjects who are aged 18 and above and diagnosed with major depressive disorder (MDD) will be recruited in this study. All subjects will be computer randomised into either the intervention group or the waitlist control group, balanced by gender and age on a 1:1 ratio.

Intervention

All subjects in each group will have to undertake functional MRI (fMRI) before and after six 30-min TPS sessions, which will be completed in 2 weeks' time.

Outcomes

Baseline measurements and post-TPS evaluation of the psychological outcomes (i.e., depression, cognition, anhedonia, and instrumental activities of daily living) will also be conducted on all participants. A 3-month follow-up period will be usedto assess the long-term sustainability of the TPS intervention. For statistical analysis, ANOVA with repeated measures will be used to analyse data. Missing data were managed by multiple mutations. The level of significance will be set to p < 0.05.

Significance of the Study

Results of this study will be used to inform health policy to determine whether TPS could be considered as a top treatment option for MDD.

Clinical Trial Registration

ClinicalTrials.gov, identifier: NCT05006365.

Electroconvulsive shock increases neurotrophy and neurogenesis: Time course and treatment session effects

Increasing evidence suggests that hippocampal neurotrophy may be related to the development of major depressive disorders. Neurogenesis, which can be regulated by neurotrophic factors, is also involved in antidepressant efficacy. This paper reviewed literature on neurotrophic signaling and cell proliferation after electroconvulsive shock (ECS) treatment. All articles were from PubMed, Web of Science, and Scopus databases between 2000 and 2020. The keywords used in the literature search are: "ECS," "ECT," "electroconvulsive seizure," "electroconvulsive shock," "electroconvulsive therapy," "neurotrophic factor," "nerve growth factor," "neurotrophins," "neurogenesis," and "cell proliferation." Eighty-two articles were included in the final analysis. It was shown that compared with acute ECS, repeated ECS increased neurotrophin expression in more brain regions at higher levels and was maintained for a longer time. Similarly, ECS increased cell proliferation in a dose- and time-dependent manner. The increase in cell proliferation was positively correlated with the amount of ECS administered and the newly born cells survived for a long time. The effects of ECS in inducing increases in neurotrophin levels and neurogenesis may contribute to brain function changes and antidepressant effects. Future research may focus on optimal sessions of ECT treatment to obtain the best therapeutic effect.

Predictive roles of brain-derived neurotrophic factor Val66Met polymorphism on antidepressant efficacy of different forms of prefrontal brain stimulation monotherapy: A randomized, double-blind, sham-controlled study

BACKGROUND

Although repetitive transcranial magnetic stimulation (rTMS) and prolonged intermittent theta-burst stimulation (piTBS) can induce changes in synaptic plasticity, the influence of brain-derived neurotrophic factor (BDNF) genotypes on their antidepressant effects remain unknown. Hence, we investigated the BDNF polymorphism contribution to the antidepressant effect of different forms left-sided prefrontal stimulations in a randomized, sham-controlled study METHODS: Seventy-five patients with medication-resistant depression were randomly assigned into three monotherapy groups: piTBS, high-frequency(HF) rTMS, or sham. The acute treatment period was two weeks. 17-item Hamilton Depression Rating scale (HDRS-17) were applied at baseline, week-1, and week-2. The primary outcome was percentage changes of HDRS-17 (%HDRS-17 changes) analyzed by generalized estimating equation (GEE) model.

RESULTS

The GEE analysis revealed a significant interaction between group, time, and BDNF genotypes effects on %HDRS-17 changes over time.  In patients carrying Val homozygotes, piTBS and HF-rTMS both exhibited significantly greater %HDRS reduction than sham at week-2. In Met carriers, only piTBS showed better efficacy than sham at week-2 (piTBS vs. sham, -41.1% vs.-18.9%, p=0.004). Regarding the influence of different BDNF genotypes on antidepressant efficacy in each intervention, only HF-rTMS exhibited significantly different degrees of %HDRS-17 changes between Val homozygotes and Met carriers (-68.5% vs. -26.4%, p=0.012, respectively), but piTBS delivered the consistent efficacy regardless of the BDNF polymorphism.

CONCLUSIONS

This is the first study to confirm the different impacts of BDNF genotypes on the effect of different left-sided prefrontal brain stimulation. BDNF Val66Met polymorphism may play a role in the antidepressant response of piTBS and HF-rTMS. (Trial Registration Number UMIN-CTR:UMIN000020892: Registration date: Feb.4, 2016).

Glial Purinergic Signals and Psychiatric Disorders

Emotion-related neural networks are regulated in part by the activity of glial cells, and glial dysfunction can be directly related to emotional diseases such as depression. Here, we discuss three different therapeutic strategies involving astrocytes that are effective for treating depression. First, the antidepressant, fluoxetine, acts on astrocytes and increases exocytosis of ATP. This has therapeutic effects via brain-derived neurotrophic factor-dependent mechanisms. Second, electroconvulsive therapy is a well-known treatment for drug-resistant depression. Electroconvulsive therapy releases ATP from astrocytes to induce leukemia inhibitory factors and fibroblast growth factor 2, which leads to antidepressive actions. Finally, sleep deprivation therapy is well-known to cause antidepressive effects. Sleep deprivation also increases release of ATP, whose metabolite, adenosine, has antidepressive effects. These independent treatments share the same mechanism, i.e., ATP release from astrocytes, indicating an essential role of glial purinergic signals in the pathogenesis of depression.

Correlation between Post-Acute Electroconvulsive Therapy Alpha-Band Spectrum Power Increase and Improvement of Psychiatric Symptoms

The results of quantitative electroencephalography (qEEG) studies on electroconvulsive therapy (ECT) have been inconsistent, and indicators of the efficacy of ECT have not been clearly identified. In this study, we examined whether qEEG could be used as an indicator of the effect of ECT by measuring it during the course of treatment. We analyzed qEEG data before and after acute-phase ECT in 18 patients with schizophrenia, mood disorders, and other psychiatric disorders. We processed the qEEG data and compared the spectral power between the data acquired before and after ECT. The spectral power increased significantly after ECT in the delta, theta, and alpha bands. There was a strong significant correlation between the increase in the spectral power of the alpha band after acute ECT and improvement in the Brief Psychiatric Rating Scale score. Our results suggest that an increase in the alpha-band spectral power may be useful as an objective indicator of the treatment effect of acute ECT.

The Influence of Psychotherapy on Peripheral Brain-Derived Neurotrophic Factor Concentration Levels and Gene Methylation Status: A Systematic Review

Psychotherapy is a well-established method of treating many mental disorders. It has been proven that psychotherapy leads to structural and functional changes in the brain; however, knowledge about the molecular and cellular mechanisms of these changes is limited. Neuroplasticity and one of its mediators, brain-derived neurotrophic factor (BDNF), are potential research targets in this field. To define the role of BDNF concentration in serum, or in plasma, and BDNF promoter gene methylation in saliva or leucocytes, in psychotherapy, an extensive literature search was conducted in the PubMed and Web of Science databases. The literature review was conducted based on papers published up until May 2021 that included pre and post psychotherapy measurements of either BDNF concentration levels or promoter gene methylation status. Ten studies were indicated as eligible for analysis: eight studies that investigated peripheral BDNF concentration levels, one study that investigated methylation status, and one study that included an evaluation of both subject matters. Patients underwent cognitive behavioral therapy or interpersonal psychotherapy. Patients were diagnosed with borderline personality disorder, major depressive disorder, anorexia nervosa, bulimia nervosa, or post-traumatic stress disorder. There were only three of the nine studies that showed statistically significant increases in BDNF concentration levels after psychotherapy. The two studies that involved BDNF gene methylation status showed a decrease in methylation after dialectical behavioral therapy of borderline patients.

Molecular Biomarkers of Electroconvulsive Therapy Effects and Clinical Response: Understanding the Present to Shape the Future

Electroconvulsive therapy (ECT) represents an effective intervention for treatment-resistant depression (TRD). One priority of this research field is the clarification of ECT response mechanisms and the identification of biomarkers predicting its outcomes. We propose an overview of the molecular studies on ECT, concerning its course and outcome prediction, including also animal studies on electroconvulsive seizures (ECS), an experimental analogue of ECT. Most of these investigations underlie biological systems related to major depressive disorder (MDD), such as the neurotrophic and inflammatory/immune ones, indicating effects of ECT on these processes. Studies about neurotrophins, like the brain-derived neurotrophic factor (BDNF) and the vascular endothelial growth factor (VEGF), have shown evidence concerning ECT neurotrophic effects. The inflammatory/immune system has also been studied, suggesting an acute stress reaction following an ECT session. However, at the end of the treatment, ECT produces a reduction in inflammatory-associated biomarkers such as cortisol, TNF-alpha and interleukin 6. Other biological systems, including the monoaminergic and the endocrine, have been sparsely investigated. Despite some promising results, limitations exist. Most of the studies are concentrated on one or few markers and many studies are relatively old, with small sample sizes and methodological biases. Expression studies on gene transcripts and microRNAs are rare and genetic studies are sparse. To date, no conclusive evidence regarding ECT molecular markers has been reached; however, the future may be just around the corner.

Electric neurostimulation regulates microglial activation via retinoic acid receptor α signaling

Brain stimulation by electroconvulsive therapy is effective in neuropsychiatric disorders by unknown mechanisms. Microglial toxicity plays key role in neuropsychiatric, neuroinflammatory and degenerative diseases. We examined the mechanism by which electroconvulsive seizures (ECS) regulates microglial phenotype and response to stimuli. Microglial responses were examined by morphological analysis, Iba1 and cytokine expression. ECS did not affect resting microglial phenotype or morphology but regulated their activation by Lipopolysaccharide stimulation. Microglia were isolated after ECS or sham sessions in naïve mice for transcriptome analysis. RNA sequencing identified 141 differentially expressed genes. ECS modulated multiple immune-associated gene families and attenuated neurotoxicity-associated gene expression. Blood brain barrier was examined by injecting Biocytin-TMR tracer. There was no breakdown of the BBB, nor increase in gene-signature of peripheral monocytes, suggesting that ECS effect is mainly on resident microglia. Unbiased analysis of regulatory sequences identified the induction of microglial retinoic acid receptor α (RARα) gene expression and a putative common RARα-binding motif in multiple ECS-upregulated genes. The effects of AM580, a selective RARα agonist on microglial response to LPS was examined in vitro. AM580 prevented LPS-induced cytokine expression and reactive oxygen species production. Chronic murine experimental autoimmune encephalomyelitis (EAE) was utilized to confirm the role RARα signaling as mediator of ECS-induced transcriptional pathway in regulating microglial toxicity. Continuous intracerebroventricular delivery of AM580 attenuated effectively EAE severity. In conclusion, ECS regulates CNS innate immune system responses by activating microglial retinoic acid receptor α pathway, signifying a novel therapeutic approach for chronic neuroinflammatory, neuropsychiatric and neurodegenerative diseases.

Brain-Derived Neurotrophic Factor Signaling in Depression and Antidepressant Action

Neurotrophic factors, particularly BDNF (brain-derived neurotrophic factor), have been associated with depression and antidepressant drug action. A variety of preclinical and clinical studies have implicated impaired BDNF signaling through its receptor TrkB (neurotrophic receptor tyrosine kinase 2) in the pathophysiology of mood disorders, but many of the initial findings have not been fully supported by more recent meta-analyses, and more both basic and clinical research is needed. In contrast, increased expression and signaling of BDNF has been repeatedly implicated in the mechanisms of both typical and rapid-acting antidepressant drugs, and recent findings have started to elucidate the mechanisms through which antidepressants regulate BDNF signaling. BDNF is a critical regulator of various types of neuronal plasticities in the brain, and plasticity has increasingly been connected with antidepressant action. Although some equivocal data exist, the hypothesis of a connection between neurotrophic factors and neuronal plasticity with mood disorders and antidepressant action has recently been further strengthened by converging evidence from a variety of more recent data reviewed here.

Methylome-wide change associated with response to electroconvulsive therapy in depressed patients

Electroconvulsive therapy (ECT) is a quick-acting and powerful antidepressant treatment considered to be effective in treating severe and pharmacotherapy-resistant forms of depression. Recent studies have suggested that epigenetic mechanisms can mediate treatment response and investigations about the relationship between the effects of ECT and DNA methylation have so far largely taken candidate approaches. In the present study, we examined the effects of ECT on the methylome associated with response in depressed patients (n = 34), testing for differentially methylated CpG sites before the first and after the last ECT treatment. We identified one differentially methylated CpG site associated with the effect of ECT response (defined as >50% decrease in Hamilton Depression Rating Scale score, HDRS), TNKS (q < 0.05; p = 7.15 × 10^-8). When defining response continuously (ΔHDRS), the top suggestive differentially methylated CpG site was in FKBP5 (p = 3.94 × 10^-7). Regional analyses identified two differentially methylated regions on chromosomes 8 (Šídák's p = 0.0031) and 20 (Šídák's p = 4.2 × 10^-5) associated with ΔHDRS. Functional pathway analysis did not identify any significant pathways. A confirmatory look at candidates previously proposed to be involved in ECT mechanisms found CpG sites associated with response only at the nominally significant level (p < 0.05). Despite the limited sample size, the present study was able to identify epigenetic change associated with ECT response suggesting that this approach, especially when involving larger samples, has the potential to inform the study of mechanisms involved in ECT and severe and treatment-resistant depression.

Electroconvulsive Therapy and Movement Disorders. New Perspectives on A Time-Tested Therapy

Electroconvulsive therapy (ECT) has been a very well known therapy in Psychiatry for over 80 years. ECT is considered useful in treating acute mania, severe depression and other psychiatric conditions. Over time, this therapy has also been used in several movement disorders including Parkinson disease (PD) and Huntington disease (HD). In this brief review, I summarize the recent History and evolution of ECT, its proven and potential applications in movement disorders as well as its potential mechanisms.

Acupuncture for comorbid mild-moderate depression and chronic musculoskeletal pain: study protocol for a randomized controlled trial

Background

Depression and chronic musculoskeletal pain (CMSP) are the leading causes of years lived with disabling diseases worldwide. Moreover, they often commonly coexist, which makes diagnosis and treatment difficult. A safe and effective treatment is urgently needed. Previous studies have shown that acupuncture is a cost-effective treatment for simple depression or CMSP. However, there is limited evidence that acupuncture is effective for depression comorbid with CMSP.

Methods

This is a randomized, sham acupuncture-controlled trial with three arms: real acupuncture (RA), sham acupuncture (SA), and healthy control (HC). Forty-eight depression combined CMSP participants and 12 healthy people will be recruited from GDTCM hospital and randomized 2:2:1 to the RA, SA, and HC groups. The patients will receive RA or SA intervention for 8 weeks, and HC will not receive any intervention. Upon completion of the intervention, there will be a 4-week follow-up. The primary outcome measures will be the severity of depression and pain, which will be assessed by the Hamilton Depression Rating Scale (HAMD-17) and Brief Pain Inventory (BPI), respectively. The secondary outcome measures will be cognitive function and quality of life, which will be measured by the Montreal Cognitive Assessment (MoCA), P300, and World Health Organization Quality of Life (WHOQOL-BREF). In addition, the correlation between brain-derived neurotrophic factor (BDNF) and symptoms will also be determined.

Discussion

The aim of this study is to evaluate the clinical efficacy and underlying mechanism of acupuncture in depression comorbid with CMSP. This study could provide evidence for a convenient and cost-effective means of future prevention and treatment of combined depression and CMSP.

Trial registration

Chinese Clinical Trial Registry ChiCTR1800014754. Preregistered on 2 February 2018. The study is currently recruiting.

Cytokines changes associated with electroconvulsive therapy in patients with treatment-resistant depression: a Meta-analysis

One third of depressive patients do not achieve remission after several steps of treatment and are considered as treatment resistant. Electroconvulsive therapy (ECT) improves symptoms in 70 to 90% of such cases. Resistant depression is associated with a dysregulation of the immune system with a dysbalance between the pro- and the anti-inflammatory cytokines. Therefore, we aimed to measure the kinetic of cytokines levels before, during and at the end of ECT. To test this hypothesis, we performed a meta-analysis assessing cytokines plasma levels before, during and after ECT in patients with major depressive disorders. After a systematic database search, means and standard deviations were extracted to calculate standardized mean differences. We found that IL-6 levels increased after 1 or 2 ECT session (p = 0.01) then decrease after 4 ECT sessions (p < 0.01) with no difference at the end of ECT (p = 0.94). A small number of studies were included and there was heterogeneity across them. The present meta-analysis reveals that ECT induces an initial increase of IL-6 levels and a potential decrease of TNF-α levels. No changes on IL-4 and IL-10 levels were found. Further work is necessary to clarify the impact of ECT on peripheral cytokines.

Changes in peripheral blood compounds following psychopharmacological treatment in drug-naïve first-episode patients with either schizophrenia or major depressive disorder: a meta-analysis

BACKGROUND

This meta-analysis on peripheral blood compounds in drug-naïve first-episode patients with either schizophrenia or major depressive disorder (MDD) examined which compounds change following psychopharmacological treatment.

METHODS

The Embase, PubMed and PsycINFO databases were systematically searched for longitudinal studies reporting measurements of blood compounds in drug-naïve first-episode schizophrenia or MDD.

RESULTS

For this random-effects meta-analysis, we retrieved a total of 31 studies comprising 1818 schizophrenia patients, and 14 studies comprising 469 MDD patients. Brain-derived neurotrophic factor (BDNF) increased following treatment in schizophrenia (Hedges' g (g): 0.55; 95% confidence interval (CI) 0.39-0.70; p < 0.001) and MDD (g: 0.51; CI 0.06-0.96; p = 0.027). Interleukin (IL)-6 levels decreased in schizophrenia (g: -0.48; CI -0.85 to -0.11; p = 0.011), and for MDD a trend of decreased IL-6 levels was observed (g: -0.39; CI -0.87 to 0.09; p = 0.115). Tumor necrosis factor alpha (TNFα) also decreased in schizophrenia (g: -0.34; CI -0.68 to -0.01; p = 0.047) and in MDD (g: -1.02; CI -1.79 to -0.25; p = 0.009). Fasting glucose levels increased only in schizophrenia (g: 0.26; CI 0.07-0.44; p = 0.007), but not in MDD. No changes were found for C-reactive protein, IL-1β, IL-2 and IL-4.

CONCLUSIONS

Psychopharmacological treatment has modulating effects on BDNF and TNFα in drug-naïve first-episode patients with either schizophrenia or MDD. These findings support efforts for further research into transdiagnostic preventive strategies and augmentation therapy for those with immune dysfunctions.

Blood Brain-Derived Neurotrophic Factor (BDNF) and Major Depression: Do We Have a Translational Perspective?

Major depressive disorder (MDD) affects millions of people worldwide and is a leading cause of disability. Several theories have been proposed to explain its pathological mechanisms, and the “neurotrophin hypothesis of depression” involves one of the most relevant pathways. Brain-derived neurotrophic factor (BDNF) is an important neurotrophin, and it has been extensively investigated in both experimental models and clinical studies of MDD. Robust empirical findings have indicated an association between increased BDNF gene expression and peripheral concentration with improved neuronal plasticity and neurogenesis. Additionally, several studies have indicated the blunt expression of BDNF in carriers of the Val66Met gene polymorphism and lower blood BDNF (serum or plasma) levels in depressed individuals. Clinical trials have yielded mixed results with different treatment options, peripheral blood BDNF measurement techniques, and time of observation. Previous meta-analyses of MDD treatment have indicated that antidepressants and electroconvulsive therapy showed higher levels of blood BDNF after treatment but not with physical exercise, psychotherapy, or direct current stimulation. Moreover, the rapid-acting antidepressant ketamine has presented an early increase in blood BDNF concentration. Although evidence has pointed to increased levels of BDNF after antidepressant therapy, several factors, such as heterogeneous results, low sample size, publication bias, and different BDNF measurements (serum or plasma), pose a challenge in the interpretation of the relation between peripheral blood BDNF and MDD. These potential gaps in the literature have not been properly addressed in previous narrative reviews. In this review, current evidence regarding BDNF function, genetics and epigenetics, expression, and results from clinical trials is summarized, putting the literature into a translational perspective on MDD. In general, blood BDNF cannot be recommended for use as a biomarker in clinical practice. Moreover, future studies should expand the evidence with larger samples, use the serum or serum: whole blood concentration of BDNF as a more accurate measure of peripheral BDNF, and compare its change upon different treatment modalities of MDD.

The role of pro- and mature neurotrophins in the depression

Neurotrophic factors, which can provide nutritional support to neurons and neuronal cells, also played an important role in their proliferation and survival. As signaling molecules, it also mediated the learning, memory and other activities in the brain. The latest study shows that neurotrophic factors have diametrically opposing effects of the pro- and mature form through distinct receptors. In this review, we summarize the different forms of neurotrophic factors, related receptors, and the corresponding biological effects. More importantly, we expounded the physiology and pathology mechanisms of brain-derived neurotrophic factor(BDNF)in depression. It is hopefully to provide new idea on the relationship of neurotrophic factors and depression.

The Association Between Hypoxia Improvement and Electroconvulsive Therapy for Major Depressive Disorder

BACKGROUND

The occurrence of depression was related with a state of mild hypoxia for a long time. Hypoxia-inducible factor-2α (HIF-2α) modulates the process from acute to chronic hypoxia, consequently regulating changes in inducible nitric oxide synthase (iNOS). Increasing levels of iNOS combined with major depressive disorder (MDD) have been associated with the concentration of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), which increase the severity of depression.

OBJECTIVE

The aim was to investigate whether depressive symptoms might be improved by regulating HIF-2α levels to decrease the degree of oxidative stress and inflammation using electroconvulsive therapy (ECT).

METHODS

In this observational study, 49 MDD patients were divided into the ECT group (n=32) and control group (n=17). The Hamilton Depression Rating Scale (HAMD) was used to evaluate depressive symptoms of patients at enrollment and after 2 weeks of treatment. The levels of HIF-2α, NOS, IL-6, and TNF-α in plasma were analyzed accordingly.

RESULTS

The total score in each dimension of HAMD decreased more efficiently in the ECT group than in the control group (p < 0.05). The plasma levels of IL-6 in the ECT group were notably decreased after the 2-week treatment (t = 3.596, p = 0.001). The decreased trend to statistical significance of HIF-2α was observed after treatment in the ECT group (p = 0.091).

CONCLUSION

The present study demonstrated that the therapeutic effects of long-term ECT therapy for MDD may further benefit from and contribute to the improvement of MDD-associated chronic hypoxia.

Unfolding the Role of BDNF as a Biomarker for Treatment of Depression

Depression is a well-known disabling mental illness characterized by sadness, loss of interest in activities, and decreased energy. The symptoms of depression are usually recurrent in vulnerable individuals, and persistence of symptoms significantly impairs individuals' quality of life. The exact pathophysiology of depression remains ambiguous, though many hypotheses have been proposed. Brain-derived neurotrophic factor (BDNF) has recently been reported to play a vital role in the pathophysiology of depression. BDNF is an important neurotrophic factor found in the human brain and is involved in neuronal growth and proliferation, synaptic neurotransmission, and neuroplasticity. The neurotrophic theory of depression proposes that depression results from reduced BDNF levels in the brain, which can be treated with antidepressants to alleviate depressive behavior and increase BDNF levels. The aim of this review is to provide broad insight into the role of BDNF in the pathogenesis of depression and in antidepressant therapy. The studies mentioned in this review article greatly support the role of BDNF in the pathogenesis of depression and treatment of this disorder with antidepressants. Since abnormalities in BDNF levels lead to the production of diverse insults that amplify the development or progression of depression, it is important to study and explore BDNF impairment in relation to depression, neuroplasticity, and neurogenesis, and increasing BDNF levels through antidepressant therapy, showing positive response in the management of depression.

Time is of the essence: Coupling sleep-wake and circadian neurobiology to the antidepressant effects of ketamine

Several studies have demonstrated the effectiveness of ketamine in rapidly alleviating depression and suicidal ideation. Intense research efforts have been undertaken to expose the precise mechanism underlying the antidepressant action of ketamine; however, the translation of findings into new clinical treatments has been slow. This translational gap is partially explained by a lack of understanding of the function of time and circadian timing in the complex neurobiology around ketamine. Indeed, the acute pharmacological effects of a single ketamine treatment last for only a few hours, whereas the antidepressant effects peak at around 24 hours and are sustained for the following few days. Numerous studies have investigated the acute and long-lasting neurobiological changes induced by ketamine; however, the most dramatic and fundamental change that the brain undergoes each day is rarely taken into consideration. Here, we explore the link between sleep and circadian regulation and rapid-acting antidepressant effects and summarize how diverse phenomena associated with ketamine's antidepressant actions - such as cortical excitation, synaptogenesis, and involved molecular determinants - are intimately connected with the neurobiology of wake, sleep, and circadian rhythms. We review several recently proposed hypotheses about rapid antidepressant actions, which focus on sleep or circadian regulation, and discuss their implications for ongoing research. Considering these aspects may be the last piece of the puzzle necessary to gain a more comprehensive understanding of the effects of rapid-acting antidepressants on the brain.

Electroconvulsive stimulation attenuates chronic neuroinflammation

Electroconvulsive therapy is highly effective in resistant depression by unknown mechanisms. Microglial toxicity was suggested to mediate depression and plays key roles in neuroinflammatory and degenerative diseases, where there is critical shortage in therapies. We examined the effects of electroconvulsive seizures (ECS) on chronic neuroinflammation and microglial neurotoxicity. Electric brain stimulation inducing full tonic-clonic seizures during chronic relapsing-progressive experimental autoimmune encephalomyelitis (EAE) reduced spinal immune cell infiltration, reduced myelin and axonal loss, and prevented clinical deterioration. Using the transfer EAE model, we examined the effect of ECS on systemic immune response in donor mice versus ECS effect on CNS innate immune activity in recipient mice. ECS did not affect encephalitogenicity of systemic T cells, but it targeted the CNS directly to inhibit T cell-induced neuroinflammation. In vivo and ex vivo assays indicated that ECS suppressed microglial neurotoxicity by reducing inducible NOS expression, nitric oxide, and reactive oxygen species (ROS) production, and by reducing CNS oxidative stress. Microglia from ECS-treated EAE mice expressed less T cell stimulatory and chemoattractant factors. Our findings indicate that electroconvulsive therapy targets the CNS innate immune system to reduce neuroinflammation by attenuating microglial neurotoxicity. These findings signify a potentially novel therapeutic approach for chronic neuroinflammatory, neuropsychiatric, and neurodegenerative diseases.

Brain-Derived Neurotrophic Factor in the Cerebrospinal Fluid Increases During Electroconvulsive Therapy in Patients With Depression: A Preliminary Report

OBJECTIVE

Preclinical evidence suggests a role for brain-derived neurotrophic factor (BDNF) in the mode of action of electroconvulsive therapy (ECT). Clinical data regarding BDNF levels in serum or plasma are more inconsistent. We measured BDNF levels from the cerebrospinal fluid (CSF) in patients with major depression before and shortly after a course of ECT.

METHODS

Cerebrospinal fluid and serum BDNF levels were determined using commercially available enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

We included 9 patients with a severe depressive episode within a major depressive disorder into the study. The CSF BDNF concentrations at baseline were lower compared with those CSF BDNF levels after the complete ECT treatment (P = 0.042), whereas no such a constellation was found for serum BDNF. No associations between the BDNF levels and the amount of individual ECT sessions or the reduction of the depressive symptoms were found.

CONCLUSIONS

For the first time, it has been shown that CSF BDNF concentrations increase during a course of ECT in patients with a severe unipolar depressive episode, which is in line with the neurotrophin hypothesis as a mode of action of ECT, although it was not possible to demonstrate either a dose-effect relation or a relationship with the actual antidepressant effects in our small sample. Major limitation is the small sample size.

Does electroconvulsive therapy cause brain damage: An update

Electroconvulsive therapy (ECT) is an effective modality of treatment for a variety of psychiatric disorders. However, it has always been accused of being a coercive, unethical, and dangerous modality of treatment. The dangerousness of ECT has been mainly attributed to its claimed ability to cause brain damage. This narrative review aims to provide an update of the evidence with regard to whether the practice of ECT is associated with damage to the brain. An accepted definition of brain damage remains elusive. There are also ethical and technical problems in designing studies that look at this question specifically. Thus, even though there are newer technological tools and innovations, any review attempting to answer this question would have to take recourse to indirect methods. These include structural, functional, and metabolic neuroimaging; body fluid biochemical marker studies; and follow-up studies of cognitive impairment and incidence of dementia in people who have received ECT among others. The review of literature and present evidence suggests that ECT has a demonstrable impact on the structure and function of the brain. However, there is a lack of evidence at present to suggest that ECT causes brain damage.

Serum neurofilament light chain (NFL) remains unchanged during electroconvulsive therapy

Objectives: Although there is consistent evidence that electroconvulsive therapy (ECT) is safe and well tolerated by the majority of patients, some authors still accuse ECT to inevitably cause brain damage and permanent memory loss, assertions that may increase patients' worries about a useful treatment. Recently, the measurement of neurofilament light chain (NFL) in peripheral blood was technically implemented, permitting longitudinal analysis of this biomarker for axonal damage. NFL is part of the axonal cytoskeleton and is released into the CSF and peripheral blood in the context of neuronal damage.Methods: In our study, blood from 15 patients with major depressive disorder receiving ECT was collected before the first ECT as well as 24 h and seven days after the last ECT, respectively. NFL concentrations were analysed using the ultrasensitive single molecule array (Simoa) technology.Results: NFL concentrations did not differ between patients and healthy controls, and there was no significant change in NFL levels in the course of ECT. On the contrary, we even found a slight decrease in absolute NFL concentrations.Conclusions: Our study confirms the safety of ECT by using a most sensitive method for the detection of NFL in peripheral blood as a biomarker of neuronal damage.

The Diagnostic Value of the Combination of Serum Brain-Derived Neurotrophic Factor and Insulin-Like Growth Factor-1 for Major Depressive Disorder Diagnosis and Treatment Efficacy

BACKGROUND

Last decades of psychiatric investigations have been marked by a search for biological markers that can clarify etiology and pathogenesis, confirm the diagnosis, screen individuals at risk, define the severity, and predict the course of mental disorders. In our study, we aimed to evaluate if BDNF and IGF-1 serum concentrations separately and in combination might be used as biomarkers for major depressive disorder (MDD) diagnosis and treatment efficacy and to evaluate the relationships among those proteins and clinical parameters of MDD.

METHODS

Forty-one MDD patients (according to DSM-5) and 32 healthy controls (HC) were included in this study. BDNF and IGF-1 serum concentrations, psychopathological (MADRS, CGI) and neuropsychological parameters (PDQ-5, RAVLT, TMT-B, DSST), functioning according to Sheehan Disability Scale were analyzed in all subjects at admission and 30 MDD patients after 8 weeks of vortioxetine treatment. Correlational analyses were performed to explore relationships between BDNF and IGF-1 and clinical characteristics. AUC-ROCs were calculated to determine if the value of serum BDNF and IGF-1 levels could serve for MDD diagnosis.

RESULTS

MDD patients had significantly lower serum BDNF (727.6 ± 87.9 pg/ml vs. 853.0 ± 93.9 pg/ml) and higher serum IGF-1 levels (289.15 ± 125.3 ng/ml vs. 170.2 ± 58.2 ng/ml) compared to HC. Significant correlations were obtained between BDNF levels and MDD status, depressive episode (DE) severity, precipitating factors, executive functions disruption (TMT-B, RAVLT immediate recall scores) and all subdomains of functioning. As for IGF-1, correlations were found between IGF-1 level and MDD status, DE severity, number and duration of DE, parameters of subjective and objective cognitive functioning (PDQ-5, RAVLT, TMT-B, DSST scores), and all subdomains of functioning. The associations between IGF-1 concentrations and cognitive tests' performance were stronger than those of BDNF. Separately both BDNF and IGF-1 demonstrated good discriminating ability for MDD diagnosis with AUC of 0.840 and 0.824, respectively. However, the combination of those neurotrophins had excellent diagnostic power to discriminate MDD patients from HC, providing an AUC of 0.916. Vortioxetine treatment significantly increased BDNF and attenuated IGF-1 serum concentrations, improved all psychopathological and neuropsychological parameters and functioning.

CONCLUSIONS

The combination of IGF-1 and BDNF might be considered as a diagnostic combination for MDD.

Non-Coding RNAs in Psychiatric Disorders and Suicidal Behavior

It is well known that only a small proportion of the human genome code for proteins; the rest belong to the family of RNAs that do not code for protein and are known as non-coding RNAs (ncRNAs). ncRNAs are further divided into two subclasses based on size: 1) long non-coding RNAs (lncRNAs; >200 nucleotides) and 2) small RNAs (<200 nucleotides). Small RNAs contain various family members that include microRNAs (miRNAs), small interfering RNAs (siRNAs), piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and small nuclear RNAs (snRNAs). The roles of ncRNAs, especially lncRNAs and miRNAs, are well documented in brain development, homeostasis, stress responses, and neural plasticity. It has also been reported that ncRNAs can influence the development of psychiatric disorders including schizophrenia, major depressive disorder, and bipolar disorder. More recently, their roles are being investigated in suicidal behavior. In this article, we have comprehensively reviewed the findings of lncRNA and miRNA expression changes and their functions in various psychiatric disorders including suicidal behavior. We primarily focused on studies that have been done in postmortem human brain. In addition, we have briefly reviewed the role of other small RNAs (e.g. piwiRNA, siRNA, snRNA, and snoRNAs) and their expression changes in psychiatric illnesses.

BDNF and the Antidepressant Effects of Ketamine and Propofol in Electroconvulsive Therapy: A Preliminary Study

OBJECTIVE

Ketamine and propofol have become increasingly popular in electroconvulsive therapy (ECT) anaesthesia. This study was conducted to examine whether changes in serum levels of brain-derived neurotrophic factor (BDNF) are associated with the antidepressant effects of ketofol, a combination of ketamine and propofol, in ECT for patients with treatment-resistant depression (TRD).

METHODS

Thirty patients with TRD (18-65 years) were enrolled and underwent eight ECT sessions with ketamine (0.5 mg/kg) plus propofol (0.5 mg/kg) (ketofol). Symptom severity was monitored using the 17-item Hamilton Depression Rating Scale (HAMD-17) and the Brief Psychiatric Rating Scale (BPRS), and serum levels of BDNF were examined by enzyme-linked immunosorbent assay (ELISA) at baseline and after 2, 4, and 8 ECT treatments. Serum levels of BDNF were also collected from thirty healthy controls.

RESULTS

At baseline, there were no significant differences in serum levels of BDNF between patients with TRD and healthy controls. The response and remission rates in patients with TRD were 100% (30/30) and 53.3% (16/30) after ECT treatment, respectively. Despite a significant reduction in HAMD-17 and BPRS scores after ECT, no changes in serum levels of BDNF were observed after ECT treatment when compared to baseline. No association was found between serum levels of BDNF and changes in illness severity.

CONCLUSION

Serum levels of BDNF did not represent a suitable candidate biomarker for determining the antidepressant effects of ketofol during ECT for patients with TRD.