Effects of electroconvulsive therapy on serum levels of brain-derived neurotrophic factor and nerve growth factor in treatment resistant major depression

Anti-neuroinflammatory microRNA-146a-5p as a potential biomarker for neuronavigation-guided rTMS therapy success in medication resistant depression disorder

Treatment-resistant depression (TRD) is a challenging issue to address. Repetitive transcranial magnetic stimulation (rTMS) is commonly used but shows varying efficacy, necessitating a deeper understanding of depression physiology and rTMS mechanisms. Notably, an increasing amount of recent data has displayed the connection of TRD and its clinical outcome with chronic inflammatory processes. The current study included 19 TRD patients undergoing rTMS and 11 depressed patients responding to medication as a comparison group. We assessed therapeutic efficacy using MADRS, HAM-D-17, GAD-7, and PHQ-9 tests. Inflammatory markers, neurotrophins, and associated miRNAs were measured in patients blood serum before and during treatment. A control group of 18 healthy individuals provided baseline data. The results of our study showed significantly higher levels of pro-inflammatory interleukins-6 and - 8 in TRD patients compared to drug-responders, which also related to more severe symptoms before treatment. In addition, TRD patients, both before and during treatment, exhibited higher average blood serum concentrations of pro-inflammatory interleukin-18 and lower levels of anti-neuroinflammatory miR-146a-5p compared to healthy controls. We also observed that the expression of miR-16-5p, miR-93-5p, and especially miR-146a-5p correlated with clinical changes following rTMS. Our study confirmed that TRD patients possess a higher inflammatory status, while the anti-neuroinflammatory miR-146a-5p was demonstrated to have a considerable potential for predicting their rTMS treatment success.

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.

The Serum Brain-Derived Neurotrophic Factor Increases in Serotonin Reuptake Inhibitor Responders Patients with First-Episode, Drug-Naïve Major Depression

Brain-derived neurotrophic factor (BDNF) is a growth factor synthesized in the cell bodies of neurons and glia, which affects neuronal maturation, the survival of nervous system, and synaptic plasticity. BDNF play an important role in the pathophysiology of major depression (MD). The serum BDNF levels changed over time, or with the improvement in depressive symptoms. However, the change of serum BDNF during pharmacotherapy remains obscure in MDD. In particular, the changes in serum BDNF associated with pharmacotherapy have not yet been fully elucidated. The present study aimed to compare the changes in serum BDNF concentrations in first-episode, drug-naive patients with MD treated with antidepressants between treatment-response and treatment-nonresponse groups. The study included 35 inpatients and outpatients composed of 15 males and 20 females aged 36.7 ± 6.8 years at the Department of Psychiatry of our University Hospital. All patients met the DSM-5 diagnostic criteria for MD. The antidepressants administered included paroxetine, duloxetine, and escitalopram. Severity of depressive state was assessed using the 17-item HAMD before and 8 weeks after drug administration. Responders were defined as those whose total HAMD scores at 8 weeks had decreased by 50% or more compared to those before drug administration, while non-responders were those whose total HAMD scores had decreased by less than 50%. Here we showed that serum BDNF levels were not significantly different at any point between the two groups. The responder group, but not the non-responder group, showed statistically significant changes in serum BDNF 0 and serum BDNF 8. The results suggest that the changes of serum BDNF might differ between the two groups. The measurement of serum BDNF has the potential to be a useful predictor of pharmacotherapy in patients with first-episode, drug-naïve MD.

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.

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.

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.

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.

[Electroconvulsive therapy in treatment of resistant schizophrenia: biological markers of efficacy and safety]

AIM

To evaluate clinical and biological efficacy and safety of electroconvulsive therapy (ECT) in patients with treatment-resistant paranoid schizophrenia.

MATERIAL AND METHODS

Determination of CNS specific biological markers (BDNF, NSE, S100B), together with markers of inflammation and CNS alteration (IL-2, CPK, CPK-MB), and clinical evaluation were performed in two groups of patients: the ECT + antipsychotic treatment group (n=66) and the antipsychotic treatment group (n=32).

RESULTS AND CONCLUSION

In the ECT + antipsychotic treatment group, the more pronounced reduction of psychotic symptoms has been revealed compared with subjects on antipsychotic treatment as monotherapy. Patients receiving ECT showed no increase in plasma levels of inflammation and CNS alteration biomarkers (NSE, S100B, CPK, CPK-MB, IL-2). The plasma level of BDNF, capable to characterize both the efficacy and safety of antipsychotic therapy, had a more pronounced upward trend in subjects with combined electroconvulsive and antipsychotic treatment, which may indicate good tolerability and high effectiveness of ECT.

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.

Repetitive transcranial magnetic stimulation increases serum brain-derived neurotrophic factor and decreases interleukin-1β and tumor necrosis factor-α in elderly patients with refractory depression

Objective

To investigate the effects of repetitive transcranial magnetic stimulation (rTMS) on serum levels of brain-derived neurotrophic factor (BDNF), interleukin (IL)-1β, and tumor necrosis factor (TNF)-α in elderly patients with refractory depression.

Methods

A total of 58 elderly patients diagnosed with refractory depression between January 2015 and December 2016 were divided randomly into two groups: 29 patients who received rTMS and 29 controls without rTMS. Thirty healthy individuals were also enrolled and all received rTMS. Serum levels of BDNF, IL-1β, and TNF-α were measured before the study (0 days), and at 48 hours and 1, 2, 3, and 4 weeks after the first TMS treatment.

Results

BDNF levels gradually increased with treatment duration in the rTMS group and were significantly higher compared with the control group. In contrast, IL-1β and TNF-α levels gradually decreased and were significantly lower than in the control group. None of the serum factors were affected by rTMS in the healthy individuals. BDNF levels were negatively correlated and IL-1β and TNF-α levels were positively correlated with Hamilton Depression Rating Scale-24 scores.

Conclusion

These results suggest that rTMS may increase BDNF and decrease IL-1β and TNF-α serum levels in elderly patients with refractory depression.

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.

Suggested Biomarkers for Major Depressive Disorder

Currently, the diagnosis of major depressive disorder (MDD) mainly relies on clinical examination and subjective evaluation of depressive symptoms. There is no non-invasive, quantitative test available today for the diagnosis of MDD. In MDD, exploration of biomarkers will be helpful in diagnosing the disorder as well as in choosing a treatment, and predicting the treatment response. In this article, it is aimed to review the findings of suggested biomarkers such as growth factors, cytokines and other inflammatory markers, oxidative stress markers, endocrine markers, energy balance hormones, genetic and epigenetic features, and neuroimaging in MDD and to evaluate how these findings contribute to the pathophysiology of MDD, the prediction of treatment response, severity of the disorder, and identification of subtypes. Among these, the findings related to the brain-derived neurotrophic factor, the hypothalamo-pituitary-adrenal axis, cytokines, and neuroimaging may be strong candidates for being biomarkers MDD, and may provide critical information in understanding biological etiology of depression. Although the findings are not sufficient yet, we think that the results of epigenetic studies will also provide very important contributions to the biomarker research in MDD. The availability of biomarkers in MDD will be an advancement that will facilitate the diagnosis of the disorder, treatment choices in the early stages, and prediction of the course of the disorder.

Growth Factor Proteins and Treatment-Resistant Depression: A Place on the Path to Precision

Background: Since the neurotrophic hypothesis of depression was formulated, conflicting results have been reported regarding the role of growth factor proteins in depressed patients, including whether there are state or trait alterations found in patients compared to controls and whether they represent predictors of treatment response. Recently it has been hypothesized that heterogeneity of findings within this literature might be partly explained by participants' history of treatment-resistant depression. This study aimed to investigate the role of growth factor proteins in patients with treatment-resistant depression (TRD) undergoing an inpatient intervention. Methods: Blood samples were collected from 36 patients with TRD and 36 matched controls. Patients were assessed both at admission and discharge from a specialist inpatient program. We examined serum biomarker differences between patients and non-depressed matched controls, longitudinal changes after inpatient treatment and relationship to clinical outcomes. Additionally, the influence of potential covariates on biomarker levels were assessed. Results: Patients displayed lower serum levels of brain-derived neurotrophic factor (OR = 0.025; 95% CI = 0.001, 0.500) and vascular endothelial growth factor-C (VEGFC; OR = 0.083, 95% CI = 0.008, 0.839) as well as higher angiopoietin-1 receptor (Tie2; OR = 2.651, 95% CI = 1.325, 5.303) compared to controls. Patients were stratified into responders (56%) and non-responders (44%). Lower VEGFD levels at admission predicted subsequent non-response (OR = 4.817, 95% CI = 1.247, 11.674). During treatment, non-responders showed a decrease in VEGF and VEGFC levels, while responders showed no significant changes. Conclusion: TRD patients demonstrate a deficit of peripheral growth factors and our results suggest that markers of the VEGF family might decline over time in chronically depressed patients in spite of multidisciplinary treatment. The action of angiogenic proteins may play an important role in the pathophysiology of TRD, and pending comprehensive investigation may provide important insights for the future of precision psychiatry.

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.

Peripheral blood nerve growth factor levels in major psychiatric disorders

Nerve growth factor (NGF) plays crucial roles in promoting neural growth and survival, and mediating synaptic and morphological plasticity. Several studies investigated the correlation between peripheral NGF levels and major psychiatric disorders, including schizophrenia (SCZ), major depressive disorder (MDD) and bipolar disorder (BPD); however, the findings were inconsistent. This meta-analysis sought to investigate blood NGF levels in patients with psychiatric disorders compared with healthy subjects and examined potential effects of blood fraction, medication and disease status. A total of 21 eligible studies, encompassing 1342 patients suffering from psychiatric disorders and 1225 healthy subjects, were enrolled in the present meta-analysis. No obvious publication bias was observed either for SCZ, MDD or BPD by the Begg's test (P > 0.05). Random-effects meta-analysis showed that SCZ (Z = 2.14, P = 0.033, SMD = -1.08, 95% CI = -2.07 to -0.09) and MDD (Z = 2.57, P = 0.010, SMD = -0.61, 95% CI = -1.08 to -0.14) patients had significantly reduced NGF levels, compared with healthy controls. Notably, this decrease was enhanced in un-medicated patients of SCZ (P = 0.004) and medicated or chronic patients of MDD (P < 0.001). No significant difference of NGF levels was observed between BPD patients and controls (P > 0.05). These results supported an association between the reduction of NGF levels and psychiatric disorders. It remains unclear whether the change of NGF levels is a prerequisite for its function in psychiatric disorders development or merely an epiphenomenon unrelated to the pathophysiologic mechanisms.

Premedication effect of dexmedetomidine and alfentanil on seizure time, recovery duration, and hemodynamic responses in electroconvulsive therapy

Introduction:

Electroconvulsive therapy (ECT) is an effective treatment for many mental disorders, especially severe and persistent depression, bipolar disorder, and schizophrenia. The aim of this study is to compare the effect of dexmedetomidine and alfentanil on agitation, satisfaction, seizure duration, and patients hemodynamic after ECT.

Materials and Methods:

In a three phase crossover randomized clinical trial, 75 patients aged between 18 and 50 years and candidate for ECT were enrolled and assigned into three groups (25 patients in each group). All patients, respectively, took premedication of dexmedetomidine, alfentanil, or saline in three consecutive phases. Patients received 0.5 μg/kg dexmedetomidine, 10 μg/kg alfentanil or normal saline intravenously, 10 min before induction. Finally, seizure and recovery duration, satisfaction and agitation score, and hemodynamic parameters were evaluated.

Results:

There was no significant difference about seizure duration, agitation score, and hemodynamic parameters between groups but recovery duration was significantly lower in the control group than dexmedetomidine (P = 0.016) and alfentanil group (P = 0.0001). Patients’ satisfaction was significantly higher in intervention groups (alfentanil and dexmedetomidine groups) (P = 0.0001).

Conclusion:

Given the equal effects of alfentanil and dexmedetomidine, it seems that choosing one of these two drugs for premedication of patients undergoing ECT is appropriate. Drug choice is influenced by numerous factors such as accessibility of each drug and the dominance of anesthesiologist and psychiatrist.

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.

Combining ECT with pharmacological treatment of depressed inpatients in a naturalistic study is not associated with serum BDNF level increase

BACKGROUND

BDNF blood levels are reduced in MDD. They can be increased with pharmacologic treatment and ECT, but it is not clear whether the combination of treatments promotes an additional increase. The present study aims to evaluate whether combined treatment promotes an increase in BDNF, restoring the level to that of non-depressed controls.

METHODS

Ninety-nine adult inpatients were invited to participate in this naturalistic prospective cohort study between May 2011 and April 2013. Diagnosis was made by MINI, and the symptoms were evaluated at admission and at discharge by HDRS-17. Those inpatients with a diagnosis of depression were included and divided into two groups: those who underwent combined ECT and medication (31 subjects) and those who used only pharmacotherapy (68 subjects). Serum BDNF was measured in blood samples collected at admission and discharge. One hundred healthy blood donors without any psychiatric diagnosis were included as a control group.

RESULTS

There were no significant differences in serum BDNF levels between the combined and pharmacological groups at admission and at discharge, and no significant variation in BDNF occurred in any group during the treatment. There were no interactions between time and treatment groups nor significant time effects or treatment group effects for BDNF in the Generalized Estimating Equation Model (GEE). The control group had significantly higher serum BDNF levels in comparison with each of the treatment groups at admission and discharge (p = 0.00).

CONCLUSION

Combination of ECT with pharmacological treatment did not result in increased serum BDNF levels and did not restore levels to that of controls.

Brain-Derived Neurotrophic Factor and Antidepressive Effect of Electroconvulsive Therapy: Systematic Review and Meta-Analyses of the Preclinical and Clinical Literature

Emerging data suggest that Electro-Convulsive Treatment (ECT) may reduce depressive symptoms by increasing the expression of Brain-Derived Neurotrophic Factor (BDNF). Yet, conflicting findings have been reported. For this reason we performed a systematic review and meta-analysis of the preclinical and clinical literature on the association between ECT treatment (ECS in animals) and changes in BDNF concentrations and their effect on behavior. In addition, regional brain expression of BDNF in mouse and human brains were compared using Allen Brain Atlas. ECS, over sham, increased BDNF mRNA and protein in animal brain (effect size [Hedge’s g]: 0.38―0.54; 258 effect-size estimates, N = 4,284) but not in serum (g = 0.06, 95% CI = -0.05―0.17). In humans, plasma but not serum BDNF increased following ECT (g = 0.72 vs. g = 0.14; 23 effect sizes, n = 281). The gradient of the BDNF increment in animal brains corresponded to the gradient of the BDNF gene expression according to the Allen brain atlas. Effect-size estimates were larger following more ECT sessions in animals (r = 0.37, P < .0001) and in humans (r = 0.55; P = 0.05). There were some indications that the increase in BDNF expression was associated with behavioral changes in rodents, but not in humans. We conclude that ECS in rodents and ECT in humans increase BDNF concentrations but this is not consistently associated with changes in behavior.

7,8-Dihydroxyflavone reduces sleep during dark phase and suppresses orexin A but not orexin B in mice

Brain-derived neurotrophic factor (BDNF) binds to Tropomyosin-receptor-kinase B (TrkB) receptors that regulate synaptic strength and plasticity in the mammalian nervous system. 7,8-Dihydroxyflavone (DHF) is a recently identified small molecule Trk B agonist that has been reported to ameliorate depression, attenuate the fear response, improve memory consolidation, and exert neuroprotective effects. Poor and disturbed sleep remains a symptom of major depressive disorder and most current antidepressants affect sleep. Therefore, we conducted sleep/wake recordings and concomitant measurement of brain orexins, endogenous peptides that suppress sleep, in mice for this study. Baseline polysomnograph recording was performed for 24 h followed by treatment with either 5 mg/kg of DHF or vehicle at the beginning of the dark phase. Animals were sacrificed the following day, one hour after the final treatment with DHF. Orexin A and B were quantified using ELISA and radioimmunoassay, respectively. Total sleep was significantly decreased in the DHF group, 4 h after drug administration in the dark phase, when compared with vehicle-treated animals. This difference was due to a significant decrease of non-rapid eye movement sleep, but not rapid eye movement sleep. DHF increased power of alpha and sigma bands but suppressed power of gamma band during sleep in dark phase. Interestingly, hypothalamic levels of orexin A were also significantly decreased in the DHF group (97 pg/mg) when compared with the vehicle-treated group (132 pg/mg). However, no significant differences of orexin B were observed between groups. Additionally, no change was found in immobility tests.

Plasma BDNFs level initially and post treatment in acute mania: comparison between ECT and atypical antipsychotic treatment and healthy controls

BACKGROUND

Inconsistent findings concerning brain-derived neurotrophic factor (BDNF) levels across different episodes in bipolar disorder have been reported, which is also in line with the treatment effects on BDNF levels in acute mania. We aimed to compare plasma BDNF level alterations after pure antipsychotic drug or ECT plus antipsychotic drug treatment in acute mania.

METHODS

Sixty-eight patients with mania were divided into two treatment arms: the antipsychotic treatment arm (AP) and electroconvulsive therapy (ECT)+AP arm. In addition, 30 healthy controls were included in the study.

RESULTS

There was no significant statistical difference according to mean age, education level, marital and working status between patients and healthy controls. The initial serum BDNF level in patients with acute mania was significantly lower than healthy controls. The initial BDNF level between the ECT arm and AP arm was not significant. The BDNF level decreased significantly after reaching remission in patients with acute mania. The change in BDNF level in the AP arm was not significant while in the ECT arm it was significant after treatment.

CONCLUSIONS

In this study, for the first time we revealed a significant decrease in BDNF levels after ECT sessions in acute manic patients. Besides clinical remission after treatment in acute mania, the decrement in BDNF levels does not seem to be related to clinical response. Thus cumulative effects of mood episodes for the ongoing decrease in BDNF levels might be borne in mind despite the achievement of remission and/or more time being required for an increase in BDNF levels after treatment.

Electroconvulsive therapy improves clinical manifestations of treatment-resistant depression without changing serum BDNF levels

Electroconvulsive therapy (ECT) is effective in treatment-resistant depression (TRD). It may act through intracellular process modulation, but its exact mechanism is still unknown. Animal research supports a neurotrophic effect for ECT. We aimed to investigate the association between changes in serum brain-derived neurotrophic factor (sBDNF) levels and clinical improvement following ECT in patients with TRD. Twenty-one patients with TRD (2 men, 19 women; mean age, 63.5 years; S.D., 11.9) were assessed through the Hamilton Depression Rating Scale (HDRS), the Brief Psychiatric Rating Scale (BPRS), and the Clinical Global Impressions scale, Severity (CGIs) before and after a complete ECT cycle. At the same time-points, patients underwent blood withdrawal for measuring sBDNF levels. ECT significantly reduced HDRS, BPRS, and CGIS scores, but not sBDNF levels. No significant correlation was found between sBDNF changes, and each of HDRS, BPRS, and CGIs score changes. sBDNF levels in TRD patients were low both at baseline and post-ECT. Our results do not support that improvements in TRD following ECT are mediated through increases in sBDNF levels.

Significantly lower nerve growth factor levels in patients with major depressive disorder than in healthy subjects: a meta-analysis and systematic review

INTRODUCTION

Since its discovery several decades ago, nerve growth factor (NGF) has been found to play roles in different areas, such as neurology, endocrinology, and immunology. There is some evidence linking NGF and psychiatry, including the role of NGF in subjects' response to stress, the alteration of NGF in different emotional states, and the penetration of NGF across the blood-brain barrier under specific conditions. There are many inconsistent findings regarding the differences in NGF in patients with major depressive disorder (MDD) at the present time. The aim of our study was to clarify whether NGF levels are different in MDD compared with healthy controls (HCs).

METHODS

We conducted a thorough literature search and compared peripheral NGF levels between MDD and HC through meta-analysis, and investigated possible confounding variables through meta-regression.

RESULTS

Seven studies were brought into the current meta-analysis comparing peripheral NGF in MDD and HCs. The main result was that the NGF levels were significantly lower in MDD than in HCs and that this had an inverse correlation with mean age and disease severity. In addition, meta-analysis of four articles found that the peripheral NGF levels did not change significantly before and after treatment.

CONCLUSION

Our study highlights the significant differences in peripheral NGF levels in patients with MDD. However, further exploration of the dynamic changes in peripheral NGF along with the disease course, and specific studies investigating the correlation of NGF in the peripheral and CNS environments are still needed.

Treatment-resistant Late-life Depression: Challenges and Perspectives

The current Review article provides a narrative review about the neurobiological underpinnings and treatment of treatment resistant late-life depression (TRLLD). The manuscript focuses on therapeutic targets of late-life depression, which include pharmacological, psychological, biophysical and exercise treatment approaches. Therefore, we summarize available evidences on that kind of therapies for patients suffering from late-life depression. The search for evidences of therapeutic options of late-life depression were done using searching websites as "pubmed", and using the searching terms "depression", "late-life depression", "treatment", "biophysical therapy", "exercise therapy", "pharmacological therapy" and "psychological therapy". To the end, we summarize and discuss current data, providing some directions for further research. Treatment recommendations for elderly depressive patients favour a multimodal approach, containing psychological, pharmacological and secondary biophysical therapeutic options. Particularly, a combination of psychotherapy and antidepressant medication reflects the best therapeutic option. However, mostly accepted and used is the pharmacological treatment although evidence suggests that the drug therapy is not as effective as it is in younger depressive patients. Further studies employing larger samples and longer follow-up periods are necessary and may focus on comparability of study designs and involve novel approaches to establish the validity and reliability of multimodal treatment programs.

Electroconvulsive therapy treatment in patients with somatic symptom and related disorders

OBJECTIVE

Medically unexplained somatic complaints are highly prevalent, and lead to significant impairment and disability. The number of effective treatment modalities for somatic symptom and related disorders (SSDs) or somatoform disorders (SDs) remains limited. To date, there is no formal indication for electroconvulsive therapy (ECT) in SSD or SD. We report on the largest case series to date regarding the effectiveness of ECT in patients with SSD and SD.

METHODS

A retrospective chart review of all patients treated with an index course of ECT at the Neuropsychiatric Program at the University of British Columbia Hospital from 2000 to 2010 was conducted. The primary outcomes consisted of changes in pseudoneurologic symptoms, pain symptoms, cardiopulmonary symptoms, and gastrointestinal symptoms. Complaints were examined pre- and post-ECT.

RESULTS

Twenty-eight participants were included in this study. Twenty-one participants received right unilateral ECT. Six received bifrontal ECT. One received bitemporal ECT. Eighteen of 21 participants reported improvement in pseudoneurologic symptoms; eleven of 14 participants reported improvement in pain symptoms; one participant reported improvement in cardiopulmonary symptoms; and one of two participants reported improvement in gastrointestinal symptoms. This paper discusses the putative mechanism of action of ECT in the treatment of SD/SSD.

CONCLUSION

This retrospective study suggests that ECT could be included as part of the existing treatment for refractory SSD and SD, particularly in refractory cases with comorbid mood disorders.