Electroconvulsive Therapy (ECT) increases serum Brain Derived Neurotrophic Factor (BDNF) in drug resistant depressed patients

The role of neurotrophic factors in novel, rapid psychiatric treatments

Neurotrophic factors are a family of growth factors that modulate cellular growth, survival, and differentiation. For many decades, it has been generally believed that a lack of neurotrophic support led to the decreased neuronal synaptic plasticity, death, and loss of non-neuronal supportive cells seen in neuropsychiatric disorders. Traditional psychiatric medications that lead to immediate increases in neurotransmitter levels at the synapse have been shown also to elevate synaptic neurotrophic levels over weeks, correlating with the time course of the therapeutic effects of these drugs. Recent advances in psychiatric treatments, such as ketamine and psychedelics, have shown a much faster onset of therapeutic effects (within minutes to hours). They have also been shown to lead to a rapid release of neurotrophins into the synapse. This has spurred a significant shift in understanding the role of neurotrophins and how the receptor tyrosine kinases that bind neurotrophins may work in concert with other signaling systems. In this review, this renewed understanding of synaptic receptor signaling interactions and the clinical implications of this mechanistic insight will be discussed within the larger context of the well-established roles of neurotrophic factors in psychiatric disorders and treatments.

Brain-Derived Neurotrophic Factor (BDNF) as a Predictor of Treatment Response in Major Depressive Disorder (MDD): A Systematic Review

Brain-derived neurotrophic factor (BDNF) has been studied as a biomarker of major depressive disorder (MDD). Besides diagnostic biomarkers, clinically useful biomarkers can inform response to treatment. We aimed to review all studies that sought to relate BDNF baseline levels, or BDNF polymorphisms, with response to treatment in MDD. In order to achieve this, we performed a systematic review of studies that explored the relation of BDNF with both pharmacological and non-pharmacological treatment. Finally, we reviewed the evidence that relates peripheral levels of BDNF and BDNF polymorphisms with the development and management of treatment-resistant depression.

Acute effects of a session of electroconvulsive therapy on brain-derived neurotrophic factor plasma levels

Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are neurotrophins that play critical roles in brain neuronal function. Previous studies have established the association between BDNF and NGF signaling and severe mental disorders, but changes in BDNF plasma levels and electroconvulsive therapy (ECT) response are controversial. The aim of his study was to explore the acute effects of a single session of ECT on these neurotrophins signaling. Plasma levels of BDNF and NGF and their tyrosine kinase-type receptors expression in peripheral blood mononuclear cells (PBMCs) were determined before and two hours after a single ECT session in 30 subjects with a severe mental disorder. Two hours after an ECT session we found a statistically significant decrease of BDNF plasma levels (p=0.007). We did not find significant acute effects on NGF plasma levels or receptors expression in PBMCs. We found a significant inverse correlation between the time of convulsion and BDNF plasma levels decrease (r=-0.041, p=0.024). We have identified a decrease in BDNF plasma levels after 2h of a single ECT session. These results indicate the interest for future research in the role of neurotrophins in the response and safety of ECT.

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.

Exploring the Therapeutic Effect of Neurotrophins and Neuropeptides in Neurodegenerative Diseases: at a Glance

Neurotrophins and neuropeptides are the essential regulators of peripheral nociceptive nerves that help to induce, sensitize, and maintain pain. Neuropeptide has a neuroprotective impact as it increases trophic support, regulates calcium homeostasis, and reduces excitotoxicity and neuroinflammation. In contrast, neurotrophins target neurons afflicted by ischemia, epilepsy, depression, and eating disorders, among other neuropsychiatric conditions. Neurotrophins are reported to inhibit neuronal death. Strategies maintained for "brain-derived neurotrophic factor (BDNF) therapies" are to upregulate BDNF levels using the delivery of protein and genes or compounds that target BDNF production and boosting BDNF signals by expanding with BDNF mimetics. This review discusses the mechanisms of neurotrophins and neuropeptides against acute neural damage as well as highlighting neuropeptides as a potential therapeutic agent against Parkinson's disease (PD), Huntington's disease (HD), Alzheimer's disease (AD), and Machado-Joseph disease (MJD), the signaling pathways affected by neurotrophins and their receptors in both standard and diseased CNS systems, and future perspectives that can lead to the potent application of neurotrophins and neuropeptides in neurodegenerative diseases (NDs).

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.

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.

Peripheral blood inflammatory markers in depression: Response to electroconvulsive therapy and relationship with cognitive performance

The inflammatory response may play a role in depression and the response to antidepressants. Electroconvulsive therapy (ECT), the most acutely powerful antidepressant treatment, can also affect the innate immune system. Here, we determined circulating blood concentrations of the inflammatory mediators C-reactive protein (CRP), IL-1β, IL-6, IL-10, and TNF-α in depressed patients compared to healthy controls and assessed the effect of ECT on their concentrations. Relationships between inflammatory mediator concentrations and mood/cognition scores were also explored. Plasma CRP, IL-1β, IL-6, IL-10, and TNF-α concentrations were examined in 86 depressed patients and 57 controls. Relationships between inflammatory mediators and clinical or cognitive outcomes following ECT were assessed using correlation and linear regression analyzes, respectively. CRP, IL-6, IL-10, and TNF-α were elevated in patients at baseline/pre-ECT compared to controls. However, only IL-6 and TNF-α survived adjustment for potential confounders. IL-1β was undetectable in most samples. ECT did not significantly alter plasma concentrations of any of the inflammatory mediators. No relationship was identified between CRP, IL-6, IL-10, and TNF-α and mood or neurocognitive scores. Overall, our data do not support a major role for these four inflammatory markers in clinical outcomes following ECT or in cognition.

Parsing the Network Mechanisms of Electroconvulsive Therapy

Electroconvulsive therapy (ECT) is one of the oldest and most effective forms of neurostimulation, wherein electrical current is used to elicit brief, generalized seizures under general anesthesia. When electrodes are positioned to target frontotemporal cortex, ECT is arguably the most effective treatment for severe major depression, with response rates and times superior to other available antidepressant therapies. Neuroimaging research has been pivotal in improving the field's mechanistic understanding of ECT, with a growing number of magnetic resonance imaging studies demonstrating hippocampal plasticity after ECT, in line with evidence of upregulated neurotrophic processes in the hippocampus in animal models. However, the precise roles of the hippocampus and other brain regions in antidepressant response to ECT remain unclear. Seizure physiology may also play a role in antidepressant response to ECT, as indicated by early positron emission tomography, single-photon emission computed tomography, and electroencephalography research and corroborated by recent magnetic resonance imaging studies. In this review, we discuss the evidence supporting neuroplasticity in the hippocampus and other brain regions during and after ECT, and their associations with antidepressant response. We also offer a mechanistic, circuit-level model that proposes that core mechanisms of antidepressant response to ECT involve thalamocortical and cerebellar networks that are active during seizure generalization and termination over repeated ECT sessions, and their interactions with corticolimbic circuits that are dysfunctional prior to treatment and targeted with the electrical stimulus.

Saikosaponins: A Review of Structures and Pharmacological Activities

Radix Bupleuri is a traditional medicine widely used in China and other Asian countries. Phytochemistry and pharmacology study reveal that saikosaponins(SSs) are the main bioactive compounds in Radix Bupleuri. SSs are complex compounds composed of triterpene aglycone and carbohydrate part containing 1-13 monosaccharides, which can be divided into seven types based on their structural characteristics. Many different kinds of SSs have been isolated from plants of Bupleurum L. SSs show a variety of biological activities, such as central nervous system protection, liver protection, antivirus, anti-tumor, anti-inflammation, hormone-like effects, and immune regulation functions. Due to their broad activity and favorable safety profile, SSs attract an increasing amount of attention in recent years. In this review, the structures of 86 SSs are summarized based on the different aglycones due to the diverse structures of saikosaponin(SS). The pharmacological effects and related mechanism of SSs are thoroughly reviewed, and perspectives for future research are further discussed.

Electroconvulsive therapy in treatment resistant depression

Electroconvulsive therapy (ECT) is a treatment modality for patients with treatment resistant depression (TRD), defined as failure of two adequate antidepressant medication trials. We provide a qualitative review of ECT's effectiveness for TRD, methods to optimize ECT parameters to improve remission rates and side effect profiles, and ECT's proposed neurobiological mechanisms. Right unilateral (RUL) electrode placement has been shown to be as effective for major depression as bilateral ECT, and RUL is associated with fewer cognitive side effects. There is mixed evidence on how to utilize ECT to sustain remission (i.e., continuation ECT, psychotropic medications alone, or a combination of ECT and psychotropic medications). Related to neurobiological mechanisms, an increase in gray matter volume in the hippocampus-amygdala complex is reported post-ECT. High connectivity between the subgenual anterior cingulate and the middle temporal gyrus before ECT is associated with better treatment response. Rodent models have implicated changes in neurotransmitters including glutamate, GABA, serotonin, and dopamine in ECT's efficacy; however, findings in humans are limited. Altogether, while ECT remains a highly effective therapy, the neurobiological underpinnings associated with improvement of depression remain uncertain.

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.

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.

Preclinical screening for antidepressant activity - shifting focus away from the Forced Swim Test to the use of translational biomarkers

Depression is the world's predominant mental health problem and a leading cause of disability. Neuropharmacological research has not yet advanced treatments to sufficiently meet clinical need, largely due to the failure of animal models to predict clinical efficacy. The forced swim test (FST) has been extensively used in the field of antidepressant research but has been under scrutiny due to its perceived severity to animals. Any use of animals in experiments and testing must have a scientific or regulatory purpose and researchers need to ensure that there is no scientifically valid alternative. However, regulatory requirements have been incorrectly cited as a reason to support the use of the FST. More research is required on tests that do not involve stressing animals as replacements for the FST. Non-behavioural neurochemical measures might provide a means to advance neuropharmacological developments while reducing animal suffering. For example, brain-derived neurotrophic factor (BDNF) may be promising.

Brain-derived neurotrophic factor (BDNF) and inflammatory markers: Perspectives for the management of depression

BACKGROUND

Mood disorders, including major depressive disorder, are among the main causes of disability and early mortality and constitute an important public health problem. Despite the search for a neurobiological explanation for these disorders, diagnosis and treatment are still based on subjective symptoms and psychometric assessments. Biomarkers, used as indicators of normal biological and pathological processes or pharmacological responses to a clinical intervention, may be useful in improving the current classification of psychiatric disorders, which can help understand the role of biological information in diagnosis, prognosis, and assessment of responses to intervention.

OBJECTIVES

This review aims to analyze the existing literature on Brain-Derived Neurotrophic Factor (BDNF) and inflammatory markers related to depression and to assess the advances and perspectives of their applicability in the diagnosis, prognosis, and assessment of responses to intervention in order to understand the importance of these biomarkers for the management of depression.

RESULTS

Evidence shows that BDNF is an important biomarker for the pathogenesis of depression; reduced levels are linked to reduced synaptic plasticity and neuronal atrophy, while elevated levels are associated with survival and neuronal differentiation, which is compatible with the neurogenic hypothesis of depression. Although the use of this biomarker is not yet established, literature shows that the concentration of BDNF is a useful measure for the differentiation between healthy and depressed individuals. Based on the inflammatory theory of depression, studies have found higher levels of inflammation in depressed individuals when compared to healthy ones, as well as an association between chronic inflammation and depressive symptoms. Studies have also found anti-inflammatory agents with anti-depressant effects. Markers such as IL-6, IL-1β, TNFα, and C-reactive protein (CRP) are potential markers of depression, but the role of cytokines in human brain activity is still insufficiently established.

CONCLUSIONS

Despite the large number of potential biological markers not yet fully established in the pathophysiology of depression, which is a challenge for psychobiology, it is clear that the concentrations of these substances are altered in psychiatric diagnoses related to the disease activity. Thus, although more research is needed, the current body of knowledge on biomarkers allows us to predict their use in the management of depression.

The effects of magnesium supplementation on serum level of brain derived neurotrophic factor (BDNF) and depression status in patients with depression

OBJECTIVE

Recent researches suggest that there is a relationship between the pathogenesis of depression and serum Brain Derived Neurotrophic Factor (BDNF) levels. Therefore, the purpose of this clinical trial was to determine effect of magnesium supplementation on serum Level of BDNF, magnesium and depression status in patients with depression.

METHODS

A double blind randomized clinical trial was conducted on 46 depressed subjects. The participants were randomly allocated into the magnesium (MG) and the placebo (PG) group and received 500 mg magnesium and placebo daily for 8 weeks. Beck's test was conducted and blood samples were taken at baseline and after the intervention period for analysis of serum magnesium and BDNF.

RESULTS

No significant differences were observed in assessed variables between the two groups at the baseline. At the end of intervention, supplementation with magnesium oxide had a significant effect on Beck's test (P = 0.01) and serum magnesium (P = 0.001), but had no significant effect on BDNF levels (P = 0.507) between the two groups.

CONCLUSIONS

Daily intake of 500 mg magnesium oxide for at least 8 weeks improved Beck's test score and serum magnesium in depressed patients, but had no significant effect on BDNF levels between the two groups, Which Further research is recommended.

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.

Time to re-engage psychiatric drug discovery by strengthening confidence in preclinical psychopharmacology

BACKGROUND

There is urgent need for new medications for psychiatric disorders. Mental illness is expected to become the leading cause of disability worldwide by 2030. Yet, the last two decades have seen the pharmaceutical industry withdraw from psychiatric drug discovery after costly late-stage trial failures in which clinical efficacy predicted pre-clinically has not materialised, leading to a crisis in confidence in preclinical psychopharmacology.

METHODS

Based on a review of the relevant literature, we formulated some principles for improving investment in translational neuroscience aimed at psychiatric drug discovery.

RESULTS

We propose the following 8 principles that could be used, in various combinations, to enhance CNS drug discovery: (1) consider incorporating the NIMH Research Domain Criteria (RDoC) approach; (2) engage the power of translational and systems neuroscience approaches; (3) use disease-relevant experimental perturbations; (4) identify molecular targets via genomic analysis and patient-derived pluripotent stem cells; (5) embrace holistic neuroscience: a partnership with psychoneuroimmunology; (6) use translational measures of neuronal activation; (7) validate the reproducibility of findings by independent collaboration; and (8) learn and reflect. We provide recent examples of promising animal-to-human translation of drug discovery projects and highlight some that present re-purposing opportunities.

CONCLUSIONS

We hope that this review will re-awaken the pharma industry and mental health advocates to the opportunities for improving psychiatric pharmacotherapy and so restore confidence and justify re-investment in the field.

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

Some evidence pointed out that Electro-Convulsive Treatment (ECT) could increase the level of brain-derived neurotrophic factor (BDNF) in depressive patients. However, there are some disagreements. The purpose of the study is through a systematic review and meta-analysis to evaluate BDNF levels after ECT in patients with Major depressive disorder. Two independent researchers searched of published articles in the databases of Cochrane Library, PubMed, MEDLINE, EMBASE and WanFang Data, from January 1990 to March 2019. The following key words were used: "depression" or "depressive disorder", "major depressive disorder", "unipolar depression", "brain-derived neurotrophic factor" or "BDNF", and "electroconvulsive" or "ECT". A total of 22 studies met the inclusion criteria of the meta-analysis and included into our analysis. BDNF levels were increased among patients with MDD after ECT (P = 0.000) in plasma samples. The standardized mean difference (SMD) was 0.695 (95 % CI: 0.402-0.988). We also found BDNF levels increased on one week and one month after finishing ECT (SMD = 0.491, 95 %CI: 0.150,0.833, P = 0.005; and SMD = 0.812, 95 %CI: 0.326,1.298, P = 0.001, respectively). Our findings suggest that BDNF levels may increase after ECT and may possibly be used as an indicator of treatment response after one or more weeks of ECT in patients with depression. However, additional investigation of BDNF levels with different ECT durations are needed in responders and non-responders.

Brain Changes Induced by Electroconvulsive Therapy Are Broadly Distributed

BACKGROUND

Electroconvulsive therapy (ECT) is associated with volumetric enlargements of corticolimbic brain regions. However, the pattern of whole-brain structural alterations following ECT remains unresolved. Here, we examined the longitudinal effects of ECT on global and local variations in gray matter, white matter, and ventricle volumes in patients with major depressive disorder as well as predictors of ECT-related clinical response.

METHODS

Longitudinal magnetic resonance imaging and clinical data from the Global ECT-MRI Research Collaboration (GEMRIC) were used to investigate changes in white matter, gray matter, and ventricle volumes before and after ECT in 328 patients experiencing a major depressive episode. In addition, 95 nondepressed control subjects were scanned twice. We performed a mega-analysis of single subject data from 14 independent GEMRIC sites.

RESULTS

Volumetric increases occurred in 79 of 84 gray matter regions of interest. In total, the cortical volume increased by mean ± SD of 1.04 ± 1.03% (Cohen's d = 1.01, p < .001) and the subcortical gray matter volume increased by 1.47 ± 1.05% (d = 1.40, p < .001) in patients. The subcortical gray matter increase was negatively associated with total ventricle volume (Spearman's rank correlation ρ = -.44, p < .001), while total white matter volume remained unchanged (d = -0.05, p = .41). The changes were modulated by number of ECTs and mode of electrode placements. However, the gray matter volumetric enlargements were not associated with clinical outcome.

CONCLUSIONS

The findings suggest that ECT induces gray matter volumetric increases that are broadly distributed. However, gross volumetric increases of specific anatomically defined regions may not serve as feasible biomarkers of clinical response.

Serum Epidermal Growth Factor is Low in Schizophrenia and Not Affected by Antipsychotics Alone or Combined With Electroconvulsive Therapy

BACKGROUND

Epidermal growth factor (EGF) is implicated in the pathogenesis of schizophrenia, suggesting possible value as a biomarker for disease severity or treatment response. However, basal EGF levels and changes during treatment are inconsistent across studies. The goal of this study is to compare serum EGF in schizophrenia patients before and after treatment with antipsychotics alone or combined with electroconvulsive therapy (ECT).

METHOD

Patients meeting DSM-IV diagnostic criteria for schizophrenia were recruited from June 2013 to December 2015 (n = 186) and followed up after 8 weeks of treatment with antipsychotics alone (n = 119, drug group) or combined with ECT (n = 67, ECT group). Serum EGF levels were measured by ELISA and compared among patients and 74 healthy control subjects. Psychopathology and clinical effects were assessed using the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Basal serum EGF was significantly lower in the entire patient cohort compared to healthy controls (P < 0.05). Repeated-measures ANOVA showed no main effect of time (F = 1.273; P = 0.261), time × group interaction (F = 1.228; P = 0.270), main effect of clinical response (F = 0.191; P = 0.663), or group × clinical interaction (F = 1.765; P = 0.186) on serum EGF. Serum EGF levels did not change significantly following antipsychotic drug or combined therapy (P > 0.05). Additionally, neither basal EGF nor EGF change was associated with the clinical response to drug or combined treatment (P > 0.05). However, baseline serum EGF was weakly associated with PANSS positive score (pretreatment: r = 0.206, posttreatment: r = 0.201) and general symptom score (pretreatment: r = -0.244). Serum EGF was also associated with duration of illness (pretreatment: r = 0.285, posttreatment: r = -0.231).

CONCLUSIONS

Serum EGF concentration is low in schizophrenia but is unchanged following treatment with antipsychotics alone or combined with ECT, regardless of clinical response. Thus, serum EGF is not a surrogate biomarker for treatment response and is unlikely to be involved in the therapeutic mechanisms of antipsychotics or ECT.

DNA Methylation of the t-PA Gene Differs Between Various Immune Cell Subtypes Isolated From Depressed Patients Receiving Electroconvulsive Therapy

BACKGROUND

Major depressive disorder (MDD) represents a tremendous health threat to the world's population. Electroconvulsive therapy (ECT) is the most effective treatment option for refractory MDD patients. Ample evidence suggests brain-derived neurotrophic factor (BDNF) to play a crucial role in ECT's mode of action. Tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) are involved in BDNF production.

HYPOTHESIS

The DNA methylation of gene regions encoding for t-PA and PAI-1 might be a suitable biomarker for ECT response prediction.

METHODS

We withdrew blood from two cohorts of treatment-resistant MDD patients receiving ECT. In the first cohort (n = 59), blood was collected at baseline only. To evaluate DNA methylation changes throughout the treatment course, we acquired a second group (n = 28) and took blood samples at multiple time points. DNA isolated from whole blood and defined immune cell subtypes (B cells, monocytes, natural killer cells, and T cells) served for epigenetic analyses.

RESULTS

Mixed linear models (corrected for multiple testing by Sidak's post-hoc test) revealed (1) no detectable baseline blood DNA methylation differences between ECT remitters (n = 33) and non-remitters (n = 53) in the regions analyzed, but (2) a significant difference in t-PA's DNA methylation between the investigated immune cell subtypes instead (p < 0.00001). This difference remained stable throughout the treatment course, showed no acute changes after ECT, and was independent of clinical remission.

CONCLUSION

DNA methylation of both proteins seems to play a minor role in ECT's mechanisms. Generally, we recommend using defined immune cell subtypes (instead of whole blood only) for DNA methylation analyses.

Repetitive enhancement of serum BDNF subsequent to continuation ECT

INTRODUCTION

Continuation electroconvulsive therapy (c-ECT) is highly effective for the prevention of depressive symptom relapse. There is a lack of understanding, about how c-ECT works in humans, particularly with regard to its effects on brain derived neurotrophic factor (BDNF) concentrations. Here, we aimed to close a gap in the literature by evaluating BDNF levels in patients receiving c-ECT.

METHODS

We included 13 patients with either unipolar or bipolar depression (mean age ± SD: 55.5 ± 17.1; f/m: 10/3; unipolar/bipolar: 10/3) who received between one and four c-ECT (average per patient: 2.8). Serum BDNF (sBDNF) levels were assessed before and after each c-ECT sessions. Clinical assessments were also administered both before and after treatment.

RESULTS

Our analysis revealed a significant increase in sBDNF after each treatment (c-ECT 1-3: P < 0.001, c-ECT 4: P = 0.018). The application of multiple c-ECT treatments was not, however, associated with further sBDNF enhancements. Psychometric scores were not significantly altered following c-ECT.

DISCUSSION

An increase in sBDNF concentrations subsequent to c-ECT parallel data from the animal literature, which has linked regularly applied electrical stimulation to neuroplastic processes. This finding suggests a relationship between ECT-induced sBDNF concentrations and (sustained) remission status, considering a stable clinical condition across c-ECT.

Obsessive-compulsive disorder and growth factors: A comparative review

The goal of this article is to clarify the role of various growth factors in the establishment and progression of obsessive-compulsive disorder (OCD). OCD is a chronic mental disorder with recurrent intrusive thoughts and/or repetitive compulsive behaviors that increase during stressful periods. Growth and neurotrophic factors may be contributing factors in the pathophysiology of OCD. Many of them are synthesized and released within the central nervous system and act as trophic agents in neurons; some of them are involved in brain growth, development, neurogenesis, myelination and plasticity, while others take part in the protection of the nervous system following brain injuries. This paper attempts to identify all articles investigating the relationship between OCD and neurotrophic and growth factors, in both animal and human studies, with a focus on adult brain studies. Based on the PubMed and Scopus and Science Direct search tools, the available articles and studies are reviewed. Out of 230 records in total, the ones related to our review topic were taken into account to further understand the pathophysiological mechanism(s) of OCD, providing methods to improve its symptoms via the modification of neurotrophins and growth factor imbalances.

BDNF Genotype and Baseline Serum Levels in Relation to Electroconvulsive Therapy Effectiveness in Treatment-Resistant Depressed Patients

OBJECTIVES

Electroconvulsive therapy (ECT) represents one of the most effective therapies for treatment-resistant depression (TRD). The brain-derived neurotrophic factor (BDNF) is a neurotrophin implicated in major depressive disorder and in the effects of different therapeutic approaches, including ECT. Both BDNF peripheral levels and Val66Met polymorphism have been suggested as biomarkers of treatment effectiveness. The objective of this study was to test the potential of serum BDNF levels and Val66Met polymorphism in predicting ECT outcome in TRD patients.

METHODS

Seventy-four TRD patients scheduled to undergo ECT were included in the study. Illness severity was assessed through the Montgomery and Asberg Depression Rating Scale before beginning ECT (T0), the day after the end of ECT (T1), and 1 month after the end of ECT (T2). At T1, patients were classified as responders/nonresponders and remitters/nonremitters, whereas at T2, they were classified as sustained responders/nonresponders and sustained remitters/nonremitters. Serum concentrations of BDNF were measured at T0, and the BDNF Val66Met polymorphism was genotyped.

RESULTS

No difference in BDNF concentrations was observed in responders versus nonresponders, in remitters versus nonremitters, in sustained responders versus sustained nonresponders, and in sustained remitters versus sustained nonremitters. No association of Val66Met polymorphism was detected with both the response and the remission status.

CONCLUSIONS

Baseline serum BDNF levels and the BDNF Val66Met polymorphism showed no clinical utility in predicting ECT outcome in TRD patients.

Brain-derived neurotrophic factor as a possible predictor of electroconvulsive therapy outcome

While brain-derived neurotrophic factor (BDNF) has been shown to predict response to pharmacotherapy in depression, studies in electroconvulsive therapy (ECT) are small and report conflicting results. This study assesses the association between pre-treatment BDNF levels and ECT outcome in severe late-life unipolar depression (LLD). The potential of BDNF as a clinical predictor of ECT outcome was subsequently evaluated. Characteristics associated with low and high BDNF subgroups were determined as well. Ninety-four patients diagnosed with LDD referred for ECT were included. Fasting serum BDNF levels were determined before ECT. Remission and response, measured with the Montgomery-Åsberg Depression Rating Scale, were the outcomes. The association between BDNF and ECT outcome was analysed with logistic regression and Cox regression. The clinical usefulness of BDNF was evaluated using the receiver operating characteristic (ROC) curve. Associations between clinical characteristics and low versus high BDNF levels were examined with T tests, chi-squared tests and Mann-Whitney tests. The odds of remission decreased with 33% for every five units increase of BDNF levels (OR 0.67, 95% confidence interval 0.47-0.96; p = 0.03); however, neither the association with time to remission nor the associations with response nor the adjusted models were significant. The area under the ROC (0.66) implied a poor accuracy of BDNF as a clinical test. Clinical characteristics associated with BDNF were inclusion site, physical comorbidities and duration of the index episode. To conclude, although there is an association between pre-treatment BDNF levels and ECT outcome, BDNF cannot be considered an eligible biomarker for ECT outcome in clinical practice.

Electroconvulsive therapy for treatment-resistant schizophrenia

BACKGROUND

Electroconvulsive therapy (ECT) involves the induction of a seizure by the administration of an electrical stimulus via electrodes usually placed bilaterally on the scalp and was introduced as a treatment for schizophrenia in 1938. However, ECT is a controversial treatment with concerns about long-term side effects such a memory loss. Therefore, it is important to determine its clinical efficacy and safety for people with schizophrenia who are not responding to their treatment.

OBJECTIVES

Our primary objective was to assess the effects (benefits and harms) of ECT for people with treatment-resistant schizophrenia.Our secondary objectives were to determine whether ECT produces a differential response in people: who are treated with unilateral compared to bilateral ECT; who have had a long (more than 12 sessions) or a short course of ECT; who are given continuation or maintenance ECT; who are diagnosed with well-defined treatment-resistant schizophrenia as opposed to less rigorously defined treatment-resistant schizophrenia (who would be expected to have a greater affective component to their illness).

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials including clinical trial registries on 9 September 2015 and 4 August 2017. There were no limitations on language, date, document type, or publication status for the inclusion of records in the register. We also inspected references of all the included records to identify further relevant studies.

SELECTION CRITERIA

Randomised controlled trials investigating the effects of ECT in people with treatment-resistant schizophrenia.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. For binary outcomes, we calculated the risk ratio (RR) and its 95% confidence intervals (CIs), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between the groups and its 95% CIs. We employed the fixed-effect model for all analyses. We assessed risk of bias for the included studies and created 'Summary of findings' tables using the GRADE framework.

MAIN RESULTS

We included 15 studies involving 1285 participants (1264 completers with an average age of 18 to 46 years) with treatment-resistant schizophrenia. We rated most studies (14/15, 93.3%) as at high risk of bias due to issues related to the blinding of participants and personnel. Our main outcomes of interest were: (i) clinically important response to treatment; (ii) clinically important change in cognitive functioning; (iii) leaving the study early; (iv) clinically important change in general mental state; (v) clinically important change in general functioning; (vi) number hospitalised; and (vii) death. No trial reported data on death.The included trials reported useable data for four comparisons: ECT plus standard care compared with sham-ECT added to standard care; ECT plus standard care compared with antipsychotic added to standard care; ECT plus standard care compared with standard care; and ECT alone compared with antipsychotic alone.For the comparison ECT plus standard care versus sham-ECT plus standard care, only average endpoint BPRS (Brief Psychiatric Rating Scale) scores from one study were available for mental state; no clear difference between groups was observed (short term; MD 3.60, 95% CI -3.69 to 10.89; participants = 25; studies = 1; very low-quality evidence). One study reported data for service use, measured as number readmitted; there was a clear difference favouring the ECT group (short term; RR 0.29, 95% CI 0.10 to 0.85; participants = 25; studies = 1; low-quality evidence).When ECT plus standard care was compared with antipsychotics (clozapine) plus standard care, data from one study showed no clear difference for clinically important response to treatment (medium term; RR 1.23, 95% CI 0.95 to 1.58; participants = 162; studies = 1; low-quality evidence). Clinically important change in mental state data were not available, but average endpoint BPRS scores were reported. A positive effect for the ECT group was found (short-term BPRS; MD -5.20, 95% CI -7.93 to -2.47; participants = 162; studies = 1; very low-quality evidence).When ECT plus standard care was compared with standard care, more participants in the ECT group had a clinically important response (medium term; RR 2.06, 95% CI 1.75 to 2.42; participants = 819; studies = 9; moderate-quality evidence). Data on clinically important change in cognitive functioning were not available, but data for memory deterioration were reported. Results showed that adding ECT to standard care may increase the risk of memory deterioration (short term; RR 27.00, 95% CI 1.67 to 437.68; participants = 72; studies = 1; very low-quality evidence). There were no clear differences between groups in satisfaction and acceptability of treatment, measured as leaving the study early (medium term; RR 1.18, 95% CI 0.38 to 3.63; participants = 354; studies = 3; very low-quality evidence). Only average endpoint scale scores were available for mental state (BPRS) and general functioning (Global Assessment of Functioning). There were clear differences in scores, favouring ECT group for mental state (medium term; MD -11.18, 95% CI -12.61 to -9.76; participants = 345; studies = 2; low-quality evidence) and general functioning (medium term; MD 10.66, 95% CI 6.98 to 14.34; participants = 97; studies = 2; very low-quality evidence).For the comparison ECT alone versus antipsychotics (flupenthixol) alone, only average endpoint scale scores were available for mental state and general functioning. Mental state scores were similar between groups (medium-term BPRS; MD -0.93, 95% CI -6.95 to 5.09; participants = 30; studies = 1; very low-quality evidence); general functioning scores were also similar between groups (medium-term Global Assessment of Functioning; MD -0.66, 95% CI -3.60 to 2.28; participants = 30; studies = 1; very low-quality evidence).

AUTHORS' CONCLUSIONS

Moderate-quality evidence indicates that relative to standard care, ECT has a positive effect on medium-term clinical response for people with treatment-resistant schizophrenia. However, there is no clear and convincing advantage or disadvantage for adding ECT to standard care for other outcomes. The available evidence was also too weak to indicate whether adding ECT to standard care is superior or inferior to adding sham-ECT or other antipsychotics to standard care, and there was insufficient evidence to support or refute the use of ECT alone. More good-quality evidence is needed before firm conclusions can be made.

Acute and subsequent continuation electroconvulsive therapy elevates serum BDNF levels in patients with major depression

INTRODUCTION

The induction of brain-derived neurotrophic factor (BDNF) release and subsequent restoration of neuroplastic homeostasis may underlie the effects of electroconvulsive therapy (ECT).

OBJECTIVES

We aimed to assess serum and plasma BDNF levels during the course of acute ECT, as well as before and after subsequent continuation ECT, in patients with depression.

METHODS

We included 24 patients with major depressive disorder (mean age ± SD: 54.5 ± 13.7; f/m: 17/7; baseline 17-item Hamilton Depression Rating Scale score of 26.79 ± 4.01). Serum and plasma BDNF (sBDNF, pBDNF) levels were assessed at nine time-points before, during, and after acute ECT series. Data were analysed using linear regression and linear mixed models, which were adjusted for multiple comparisons via Bonferroni correction. Five patients received continuation ECT subsequent to the acute ECT series. In these patients, BDNF levels were assessed before and after each two continuation ECT sessions using Wilcoxon signed-rank tests.

RESULTS

Relative to baseline (mean ng/ml ±SD: 24.68 ± 14.40), sBDNF levels were significantly higher 1 day (33.04 ± 14.11, p = 0.013, corrected), 1 week (37.03 ± 10.29, p < 0.001, corrected), and 1 month (41.05 ± 10.67, p = 0.008, corrected) after the final ECT session, while pBDNF levels did not significantly differ (p > 0.1). Furthermore, our results indicated that sBDNF levels increased after each continuation ECT session. There was no significant association between sBDNF levels and clinical parameters or treatment response.

CONCLUSION

The absence of an association between changes in sBDNF levels and depressive symptoms challenges the proposed concept of sBDNF/pBDNF as key markers of the effects of ECT.

Epistasis of HTR1A and BDNF risk genes alters cortical 5-HT1A receptor binding: PET results link genotype to molecular phenotype in depression

Alterations of the 5-HT_1A receptor and BDNF have consistently been associated with affective disorders. Two functional single nucleotide polymorphisms (SNPs), rs6295 of the serotonin 1A receptor gene (HTR1A) and rs6265 of brain-derived neurotrophic factor gene (BDNF), may impact transcriptional regulation and expression of the 5-HT_1A receptor. Here we investigated interaction effects of rs6295 and rs6265 on 5-HT_1A receptor binding. Forty-six healthy subjects were scanned with PET using the radioligand [carbonyl-¹¹C]WAY-100635. Genotyping was performed for rs6265 and rs6295. Subjects showing a genotype with at least three risk alleles (G of rs6295 or A of rs6265) were compared to control genotypes. Cortical surface binding potential (BP_ND) was computed for 32 cortical regions of interest (ROI). Mixed model was applied to study main and interaction effects of ROI and genotype. ANOVA was used for post hoc analyses. Individuals with the risk genotypes exhibited an increase in 5-HT_1A receptor binding by an average of 17% (mean BP_ND 3.56 ± 0.74 vs. 2.96 ± 0.88). Mixed model produced an interaction effect of ROI and genotype on BP_ND and differences could be demonstrated in 10 ROI post hoc. The combination of disadvantageous allelic expression of rs6295 and rs6265 may result in a 5-HT_1A receptor profile comparable to affective disorders as increased 5-HT_1A receptor binding is a well published phenotype of depression. Thus, epistasis between BDNF and HTR1A may contribute to the multifactorial risk for affective disorders and our results strongly advocate further research on this genetic signature in affective disorders.

The Involvement of Sortilin/NTSR3 in Depression as the Progenitor of Spadin and Its Role in the Membrane Expression of TREK-1

The molecular identification of sortilin, also called neurotensin receptor-3, from three different biochemical approaches already predicted the involvement of the protein in numerous biological and cellular functions. The first important observation was that sortilin is synthesized as a precursor that is converted to a mature protein after cleavage by the protein convertase furin in late Golgi compartments. This maturation leads to the formation of a 44 amino acid peptide, the propeptide (PE). The release of this peptide when matured sortilin reached the plasma membrane remained to be demonstrated. Sortilin has been also shown to be shedded by matrix metalloproteases releasing a large extracellular fragment identified as soluble sortilin. Therefore, sortilin has been shown to interact with several proteins and receptors confirming its role in the sorting of cellular components to the plasma membrane and/or to the lysosomal pathway. Interestingly, sortilin physically interacts with the two pore domain potassium channel TREK-1 and the PE as well as its synthetic analog spadin is able to block the activation of TREK-1 highlighting their role in the depression pathology. The present review describes the advance of research that led to these results and how both the soluble form of sortilin and the sortilin-derived PE have been detected in human serum and whose levels are affected in patients with major depressive disorder (MDD). The use of spadin as an antidepressant and the further role of soluble sortilin and of sortilin-derived PE as potential biomarkers during depression statement and/or remission of the pathology are considered and discussed in this review.

ECT-induced brain plasticity correlates with positive symptom improvement in schizophrenia by voxel-based morphometry analysis of grey matter

BACKGROUND

Electroconvulsive therapy (ECT) is often considered as an augmentation of antipsychotic treatment for schizophrenia in drug-refractory cases. However, the mechanisms underlying the observed therapeutic effects are still not understood.

OBJECTIVE

We aimed to investigate changes in whole brain grey matter volume (GMV) before and after modified ECT. GMV was determined using voxel-based morphometry (VBM) whole brain analysis. Correlations of brain structural changes with clinical improvement were also investigated.

METHODS

Twenty-one schizophrenia patients treated with a full course of ECT combined with antipsychotics (ECT group) and 21 schizophrenia patients treated only with antipsychotics (Drug group) were observed in parallel. Magnetic resonance imaging scans were performed at baseline (T1) and follow-up (T2) for each patient. Data were compared to a healthy control group (HC group) of 23 persons who were only scanned at baseline. Demographic data were matched between the three groups.

RESULTS

Significant interactions of group by time were found within four brain regions: the left parahippocampal gyrus/hippocampus, right parahippocampal gyrus/hippocampus, right temporal_pole_mid/superior temporal gyrus, and right insula. Post-hoc analysis revealed an increase of GMV across all four regions amongst ECT group, but a decrease of GMV within the Drug group. Furthermore, the ECT group showed a significant positive correlation of GMV change in the right parahippocampal gyrus/hippocampus with a reduction of positive subscore in the positive and negative syndrome scale. Both treatment groups did not differ significantly in terms of GMV from the HC group in these regions either at T1 or at T2.

CONCLUSION

Our findings indicate that ECT may induce brain plasticity as indexed by grey matter volume change during the treatment of schizophrenia via distinct mechanics from those by antipsychotic medications. ECT may ameliorate the positive psychotic symptoms of patients suffering from schizophrenia by preferentially targeting limbic brain areas such as the parahippocampal gyrus/hippocampus.

Effect of electroconvulsive therapy on brain-derived neurotrophic factor levels in patients with major depressive disorder

OBJECTIVES

Brain-derived neurotrophic factor (BDNF) has been associated with depression and its treatment response. The aim of the present study was to explore the effect of electroconvulsive therapy (ECT) on serum and plasma BDNF levels and change of Montgomery-Asberg Depression Rating Scale (MADRS) and their associations in patients with major depressive disorder (MDD).

METHODS

The study included thirty patients suffering from MDD. Their serum and plasma BDNF levels were examined before ECT (baseline) and after the first, fifth, and last ECT session. The severity of the depression and the response to ECT were measured with MADRS.

RESULTS

Electroconvulsive therapy caused no significant changes in serum BDNF levels. Plasma BDNF levels decreased during the fifth ECT session between the baseline and the 2-hr samples (p = 0.019). No associations were found between serum or plasma BDNF levels and remission. The correlations between plasma and serum BDNF levels in each measurement varied between 0.187 and 0.636.

CONCLUSIONS

Neither serum nor plasma BDNF levels were systematically associated with the clinical remission. However, the plasma BDNF levels somewhat varied during the ECT series. Therefore, the predictive value of BDNF for effects of ECT appears to be at least modest.

Electroconvulsive Therapy in Depression: Current Practice and Future Direction

The current practice of electroconvulsive therapy (ECT) has evolved over several decades with the implementation of safer equipment and advancement of techniques. In addition, modifications in the delivery of ECT, such as the utilization of brief and ultrabrief pulse widths and individualization of treatment parameters, have improved the safety of ECT without sacrificing efficacy. This article aims to provide psychiatrists with a balanced, in-depth look into the recent advances in ECT technique as well as the evidence of ECT for managing depression in special populations and patients with comorbid medical problems.

The Immediate Early Gene Egr3 Is Required for Hippocampal Induction of Bdnf by Electroconvulsive Stimulation

Early growth response 3 (Egr3) is an immediate early gene (IEG) that is regulated downstream of a cascade of genes associated with risk for psychiatric disorders, and dysfunction of Egr3 itself has been implicated in schizophrenia, bipolar disorder, and depression. As an activity-dependent transcription factor, EGR3 is poised to regulate the neuronal expression of target genes in response to environmental events. In the current study, we sought to identify a downstream target of EGR3 with the goal of further elucidating genes in this biological pathway relevant for psychiatric illness risk. We used electroconvulsive stimulation (ECS) to induce high-level expression of IEGs in the brain, and conducted expression microarray to identify genes differentially regulated in the hippocampus of Egr3-deficient (-/-) mice compared to their wildtype (WT) littermates. Our results replicated previous work showing that ECS induces high-level expression of the brain-derived neurotrophic factor (Bdnf) in the hippocampus of WT mice. However, we found that this induction is absent in Egr3-/- mice. Quantitative real-time PCR (qRT-PCR) validated the microarray results (performed in males) and replicated the findings in two separate cohorts of female mice. Follow-up studies of activity-dependent Bdnf exons demonstrated that ECS-induced expression of both exons IV and VI requires Egr3. In situ hybridization demonstrated high-level cellular expression of Bdnf in the hippocampal dentate gyrus following ECS in WT, but not Egr3-/-, mice. Bdnf promoter analysis revealed eight putative EGR3 binding sites in the Bdnf promoter, suggesting a mechanism through which EGR3 may directly regulate Bdnf gene expression. These findings do not appear to result from a defect in the development of hippocampal neurons in Egr3-/- mice, as cell counts in tissue sections stained with anti-NeuN antibodies, a neuron-specific marker, did not differ between Egr3-/- and WT mice. In addition, Sholl analysis and counts of dendritic spines in golgi-stained hippocampal sections revealed no difference in dendritic morphology or synaptic spine density in Egr3-/-, compared to WT, mice. These findings indicate that Egr3 is required for ECS-induced expression of Bdnf in the hippocampus and suggest that Bdnf may be a downstream gene in our previously identified biologically pathway for psychiatric illness susceptibility.

Convergent Mechanisms Underlying Rapid Antidepressant Action

Traditional pharmacological treatments for depression have a delayed therapeutic onset, ranging from several weeks to months, and there is a high percentage of individuals who never respond to treatment. In contrast, ketamine produces rapid-onset antidepressant, anti-suicidal, and anti-anhedonic actions following a single administration to patients with depression. Proposed mechanisms of the antidepressant action of ketamine include N-methyl-D-aspartate receptor (NMDAR) modulation, gamma aminobutyric acid (GABA)-ergic interneuron disinhibition, and direct actions of its hydroxynorketamine (HNK) metabolites. Downstream actions include activation of the mechanistic target of rapamycin (mTOR), deactivation of glycogen synthase kinase-3 and eukaryotic elongation factor 2 (eEF2), enhanced brain-derived neurotrophic factor (BDNF) signaling, and activation of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptors (AMPARs). These putative mechanisms of ketamine action are not mutually exclusive and may complement each other to induce potentiation of excitatory synapses in affective-regulating brain circuits, which results in amelioration of depression symptoms. We review these proposed mechanisms of ketamine action in the context of how such mechanisms are informing the development of novel putative rapid-acting antidepressant drugs. Such drugs that have undergone pre-clinical, and in some cases clinical, testing include the muscarinic acetylcholine receptor antagonist scopolamine, GluN2B-NMDAR antagonists (i.e., CP-101,606, MK-0657), (2R,6R)-HNK, NMDAR glycine site modulators (i.e., 4-chlorokynurenine, pro-drug of the glycineB NMDAR antagonist 7-chlorokynurenic acid), NMDAR agonists [i.e., GLYX-13 (rapastinel)], metabotropic glutamate receptor 2/3 (mGluR2/3) antagonists, GABAA receptor modulators, and drugs acting on various serotonin receptor subtypes. These ongoing studies suggest that the future acute treatment of depression will typically occur within hours, rather than months, of treatment initiation.

Increased serum levels of sortilin-derived propeptide after electroconvulsive therapy in treatment-resistant depressed patients

PURPOSE

Sortilin-derived propeptide (PE) and its synthetic analog spadin show strong antidepressant activity in rodents and, therefore, could be used as a biomarker to evaluate the clinical efficacy of antidepressant treatments. The aim of this study was to determine whether electroconvulsive therapy (ECT) modulates serum PE concentration in patients with treatment-resistant depression (TRD).

PATIENTS AND METHODS

Forty-five patients with major depressive disorder, who met the Diagnostic and Statistical Manual of Mental Disorders-IV criteria, were selected for this study.

RESULTS

We did not observe any difference in the PE levels between TRD patients and controls (z=0.10, P=0.92), but we found a strong significant increase between the PE levels measured just before (T0) and about 1 month (T2) after ECT (z=-2.82, P=0.005). A significant difference between T0 and T2 was observed only in responders (z=-2.59, P=0.01), whereas no effect was found in nonresponders (z=-1.27, P=0.20). Interestingly, we found a significant correlation between the increase in PE levels and decrease in Montgomery -Åsberg Depression Rating Scale scores for the total patient sample (P=0.03).

CONCLUSION

This study indicates for the first time that ECT affects serum PE concentration in responders and, therefore, could contribute to the evaluation of the therapy success.

Polymorphism of the brain-derived neurotrophic factor and dynamics of the seizure threshold of electroconvulsive therapy

During a course of electroconvulsive therapy (ECT), the level of currency necessary to induce an epileptic seizure in a patient may either remain relatively stable or-more often-may require repeated upward adjustment over time due to a constantly increasing seizure threshold. We aimed to determine whether a common polymorphism of the brain-derived neurotrophic factor (BDNF), which constitutes an important and ubiquitously expressed neurotrophine in the brain, affects the stimulation threshold of ECTs required to induce an epileptic seizure over time. Twenty-seven adult patients who underwent at least 12 consecutive ECT sessions were analyzed for the stimulation intensities required during the course of the stimulation as well as their BDNF gene status. We could not find a relation between the Val/Met polymorphism of the BDNF and the development of the seizure threshold during the course of the ECT sessions. Mechanisms and predispositions other than the BDNF polymorphism investigated in this study are responsible for the change in seizure thresholds over the course of ECT.

Translational Functional Neuroimaging in the Explanation of Depression

Translation as a notion and procedure is deeply embodied in medical science and education. Translation includes the possibility to translate data across disciplines to improve diagnosis and treatment procedures. The evidence accumulated using translation serves as a vehicle for reification of medical diagnoses. There are promising, established post hoc correlations between the different types of clinical tools (interviews and inventories) and neuroscience. The various measures represent statistical correlations that must now be integrated into diagnostic standards and procedures but this, as a whole, is a step forward towards a better understanding of the mechanisms underlying psychopathology in general and depression in particular. Here, we focus on functional magnetic resonance imaging studies using a trans-disciplinary approach and attempt to establish bridges between the different fields. We will selectively highlight research areas such as imaging genetics, imaging immunology and multimodal imaging, as related to the diagnosis and management of depression.

Saikosaponin A attenuates perimenopausal depression-like symptoms by chronic unpredictable mild stress

Accumulating studies have shown that a traditional Chinese decoction Chaihu-Shugan-San produced the antidepressant-like effects in rodents including in perimenopausal. Previous studies and our preliminary study indicated that saikosaponin A, one of the main constituents of Chaihu-Shugan-San, enhanced brain-derived neurotrophic factor (BDNF) expression in rats. Herein, this study aimed to evaluate the antidepressant-like effects of saikosaponin A in perimenopausal rats exposed to chronic unpredictable mild stress (CUMS). The sucrose preference test, novelty-suppressed feeding test and forced swimming test were performed after administration of saikosaponin A for 4 weeks. Serum corticotrophin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and corticosterone levels, as well as hypothalamus CRH and hippocampal glucocorticoid receptor were measured. In addition, pro-inflammatory cytokines such as interleukin-1beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in the hippocampus were detected for evaluation of the neuroinflammation. Further, BDNF levels and its receptor TrkB were also determined. Our results indicated that four-week treatment with saikosaponin A increased sucrose preference, decreased latency to feed in the novelty-suppressed feeding test and reduced the immobility time in the forced swimming test. In addition, saikosaponin A restored the dsyregulation of HPA axis and neuroinflammation in rats exposed to CUMS. Moreover, saikosaponin A promoted BDNF-TrkB signaling in the hippocampus. This study demonstrates that saikosaponin A produced the antidepressant-like effects in rats, which may be mediated by restoration of neuroendocrine, neuroinflammation and neurotrophic systems in the hippocampus during perimenopausal.

Mouse repeated electroconvulsive seizure (ECS) does not reverse social stress effects but does induce behavioral and hippocampal changes relevant to electroconvulsive therapy (ECT) side-effects in the treatment of depression

Electroconvulsive therapy (ECT) is an effective treatment for depression, but can have negative side effects including amnesia. The mechanisms of action underlying both the antidepressant and side effects of ECT are not well understood. An equivalent manipulation that is conducted in experimental animals is electroconvulsive seizure (ECS). Rodent studies have provided valuable insights into potential mechanisms underlying the antidepressant and side effects of ECT. However, relatively few studies have investigated the effects of ECS in animal models with a depression-relevant manipulation such as chronic stress. In the present study, mice were first exposed to chronic social stress (CSS) or a control procedure for 15 days followed by ECS or a sham procedure for 10 days. Behavioral effects were investigated using an auditory fear conditioning (learning) and expression (memory) test and a treadmill-running fatigue test. Thereafter, immunohistochemistry was conducted on brain material using the microglial marker Iba-1 and the cholinergic fibre marker ChAT. CSS did not increase fear learning and memory in the present experimental design; in both the control and CSS mice ECS reduced fear learning and fear memory expression. CSS induced the expected fatigue-like effect in the treadmill-running test; ECS induced increased fatigue in CSS and control mice. In CSS and control mice ECS induced inflammation in hippocampus in terms of increased expression of Iba-1 in radiatum of CA1 and CA3. CSS and ECS both reduced acetylcholine function in hippocampus as indicated by decreased expression of ChAT in several hippocampal sub-regions. Therefore, CSS increased fatigue and reduced hippocampal ChAT activity and, rather than reversing these effects, a repeated ECS regimen resulted in impaired fear learning-memory, increased fatigue, increased hippocampal Iba-1 expression, and decreased hippocampal ChAT expression. As such, the current model does not provide insights into the mechanism of ECT antidepressant function but does provide evidence for pathophysiological mechanisms that might contribute to important ECT side-effects.

The association of electroconvulsive therapy to pharmacological treatment and its influence on cytokines

INTRODUCTION

A growing body of evidence shows that disturbances in the immune system are involved in the pathogenesis of depression. Although the immune-modulating effects of antidepressants have been described, few studies have addressed the functioning of the immune system in relation to electroconvulsive therapy (ECT). This study aims to investigate if the addition of ECT to pharmacotherapy is associated with changes in cytokine levels.

METHODS

Adult inpatients were invited to participate in this study on admission to a psychiatric unit. Those with a diagnosis of depression by Mini-International Neuropsychiatric Interview were included. At treatment discharge, patients were retrospectively divided into those who used combined ECT and pharmacotherapy (31 subjects) and those who used only pharmacotherapy (68 subjects). Pro-inflammatory cytokines IL-2, IL-6, TNF-α, IFN-γ, and IL-17, and anti-inflammatory IL-4 and Il-10, were measured in blood samples collected at admission and discharge. A generalized estimating equation model and the post hoc Bonferroni test were performed for statistical analysis.

RESULTS

The combination of ECT with pharmacotherapy was associated with a decrease of IL-6 and an increase of TNF-α. Depressive inpatients, as a whole group, had a decrease of IL-6 and an increase of IFN-γ. No significant results were found for IL-2, IL-4, Il-10 and IL-17.

CONCLUSION

This study is clinically relevant because we highlight that, in agreement with the previous literature, IL-6 appears to be a useful marker in depression, and we show for the first time that its reduction is closely related to the use of ECT.

Electroconvulsive therapy modulates plasma pigment epithelium-derived factor in depression: a proteomics study

Electroconvulsive therapy (ECT) is the most effective treatment for severe depression, yet its mechanism of action is not fully understood. Peripheral blood proteomic analyses may offer insights into the molecular mechanisms of ECT. Patients with a major depressive episode were recruited as part of the EFFECT-Dep trial (enhancing the effectiveness of electroconvulsive therapy in severe depression; ISRCTN23577151) along with healthy controls. As a discovery-phase study, patient plasma pre-/post-ECT (n=30) was analyzed using 2-dimensional difference in gel electrophoresis and mass spectrometry. Identified proteins were selected for confirmation studies using immunodetection methods. Samples from a separate group of patients (pre-/post-ECT; n=57) and matched healthy controls (n=43) were then used to validate confirmed changes. Target protein mRNA levels were also assessed in rat brain and blood following electroconvulsive stimulation (ECS), the animal model of ECT. We found that ECT significantly altered 121 protein spots with 36 proteins identified by mass spectrometry. Confirmation studies identified a post-ECT increase (P<0.01) in the antiangiogenic and neuroprotective mediator pigment epithelium-derived factor (PEDF). Validation work showed an increase (P<0.001) in plasma PEDF in depressed patients compared with the controls that was further increased post-ECT (P=0.03). PEDF levels were not associated with mood scores. Chronic, but not acute, ECS increased PEDF mRNA in rat hippocampus (P=0.02) and dentate gyrus (P=0.03). This study identified alterations in blood levels of PEDF in depressed patients and further alterations following ECT, as well as in an animal model of ECT. These findings implicate PEDF in the biological response to ECT for depression.

Consequences of brain-derived neurotrophic factor withdrawal in CNS neurons and implications in disease

Growth factor withdrawal has been studied across different species and has been shown to have dramatic consequences on cell survival. In the nervous system, withdrawal of nerve growth factor (NGF) from sympathetic and sensory neurons results in substantial neuronal cell death, signifying a requirement for NGF for the survival of neurons in the peripheral nervous system (PNS). In contrast to the PNS, withdrawal of central nervous system (CNS) enriched brain-derived neurotrophic factor (BDNF) has little effect on cell survival but is indispensible for synaptic plasticity. Given that most early events in neuropsychiatric disorders are marked by a loss of synapses, lack of BDNF may thus be an important part of a cascade of events that leads to neuronal degeneration. Here we review reports on the effects of BDNF withdrawal on CNS neurons and discuss the relevance of the loss in disease.

The correlation between plasma brain-derived neurotrophic factor and cognitive function in bipolar disorder is modulated by the BDNF Val66Met polymorphism

We explored the effect of the Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism (rs6265) on correlation between changes in plasma BDNF levels with cognitive function and quality of life (QoL) after 12 weeks of treatment in bipolar disorder (BD). Symptom severity and plasma BDNF levels were assessed upon recruitment and during weeks 1, 2, 4, 8 and 12. QoL, the Wisconsin Card Sorting Test (WCST), and the Conners’ Continuous Performance Test (CPT) were assessed at baseline and endpoint. The BDNF Val66Met polymorphism was genotyped. Changes in cognitive function and QoL over 12 weeks were reduced using factor analysis for the evaluation of their correlations with changes in plasma BDNF. Five hundred forty-one BD patients were recruited and 65.6% of them completed the 12-week follow-up. Changes in plasma BDNF levels with factor 1 (WCST) were significantly negatively correlated (r = −0.25, p = 0.00037). After stratification of BD subtypes and BDNF genotypes, this correlation was significant only in BP-I and the Val/Met genotype (r = −0.54, p = 0.008). We concluded that changes in plasma BDNF levels significantly correlated with changes in WCST scores in BD and is moderated by the BDNF Val66Met polymorphism and the subtype of BD.

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

OBJECTIVE

We performed a systematic review and meta-analysis to estimate brain-derived neurotrophic factor (BDNF) level in patients with major depressive disorder (MDD) after electroconvulsive therapy (ECT).

METHOD

A comprehensive search of the Cochrane Library, MEDLINE, LILACS, Grey literature, and EMBASE was performed for papers published from January 1990 to April 2016. The following key terms were searched: "major depressive disorder", "unipolar depression", "brain-derived neurotrophic factor", and "electroconvulsive therapy".

RESULTS

A total of 252 citations were identified by the search strategy, and nine studies met the inclusion criteria of the meta-analysis. BDNF levels were increased among patients with MDD after ECT (P value = 0.006). The standardized mean difference was 0.56 (95% CI: 0.17-0.96). Additionally, we found significant heterogeneity between studies (I² = 73%).

CONCLUSION

Our findings suggest a potential role of BDNF as a marker of treatment response after ECT in patients with MDD.

Effect of magnesium supplementation on depression status in depressed patients with magnesium deficiency: A randomized, double-blind, placebo-controlled trial

OBJECTIVES

The aim of this study was to determine the effect of magnesium supplementation on the depression status of depressed patients suffering from magnesium deficiency.

METHODS

Sixty depressed people suffering from hypomagnesemia participated in this trial. The individuals were randomly categorized into two groups of 30 members; one receiving two 250-mg tablets of magnesium oxide (MG) daily and the other receiving placebo (PG) for 8 wk. The Beck Depression Inventory-II was conducted and the concentration of serum magnesium was measured.

RESULTS

At the end of intervention, 88.5% of the MG and 48.1% of the PG (P = 0.002) had a normal level of magnesium. The mean changes of serum magnesium were significantly different across the two groups. After the intervention, the mean Beck score significantly declined. However, in the MG, this reduction was more significant than in the PG (P = 0.02), so that the mean changes in this group experienced 15.65 ± 8.9 reduction, but in the PG, it declined by 10.40 ± 7.9.

CONCLUSIONS

Daily consumption of 500 mg magnesium oxide tablets for ≥8 wk by depressed patients suffering from magnesium deficiency leads to improvements in depression status and magnesium levels. Therefore, assessment of the magnesium serum and resolving this deficiency positively influence the treatment of depressed patients.

Study protocol for a randomized controlled trial to explore the effects of personalized lifestyle advices and tandem skydives on pleasure in anhedonic young adults

BACKGROUND

Anhedonia is generally defined as the inability to feel pleasure in response to experiences that are usually enjoyable. Anhedonia is one of the two core symptoms of depression and is a major public health concern. Anhedonia has proven particularly difficult to counteract and predicts poor treatment response generally. It has often been hypothesized that anhedonia can be deterred by a healthy lifestyle. However, it is quite unlikely that a one-size-fits-all approach will be effective for everyone. In this study the effects of personalized lifestyle advice based on observed individual patterns of lifestyle behaviors and experienced pleasure will be examined. Further, we will explore whether a tandem skydive following the personalized lifestyle advice positively influences anhedonic young adults' abilities to carry out the recommended lifestyle changes, and whether this ultimately improves their self-reported pleasure.

METHODS

Our study design is an exploratory intervention study, preceded by a cross-sectional survey as a screening instrument. For the survey, 2000 young adults (18-24 years old) will be selected from the general population. Based on survey outcomes, 72 individuals (36 males and 36 females) with persistent anhedonia (i.e., more than two months) and 60 individuals (30 males and 30 females) without anhedonia (non-anhedonic control group) will be selected for the intervention study. The non-anhedonic control group will fill out momentary assessments of pleasure and lifestyle behaviors three times a day, for one month. The anhedonic individuals will fill out momentary assessments for three consecutive months. After the first month, the anhedonic individuals will be randomly assigned to (1) no intervention, (2) lifestyle advice only, (3) lifestyle advice plus tandem skydive. The personalized lifestyle advice is based on patterns observed in the first month.

DISCUSSION

The present study is the first to examine the effects of a personalized lifestyle advice and tandem skydive on pleasure in anhedonic young adults. Results of the present study may improve treatment for anhedonia, if the interventions are found to be effective.

TRIAL REGISTRATION

Dutch Trial Register, NTR5498 , registered September 22, 2015 (retrospectively registered).