Brain-derived Neurotrophic Factor Level and Gene Polymorphism as Risk Factors for Depression in Patients with type 2 Diabetes Mellitus- A Case-Controlled Study

BACKGROUND

Diabetes mellitus and depression are comorbidities that can be caused by each other. Brain-derived neurotrophic factor (BDNF) functions as a neuronal growth factor. It maintains the functional integrity of the nervous system.

AIM

To study the possible association between BDNF levels and gene polymorphism with depression in patients diagnosed with type 2 diabetes mellitus.

METHODS

The Elisa technique measured BDNF, and rs6265 gene polymorphism was detected using real-time PCR. Depression was assessed utilizing a clinical interview tool designed to establish the diagnosis of depression and differentiate it from other psychiatric diseases.

RESULTS

BDNF levels were significantly lower in patients with type 2 diabetes mellitus and symptoms of depression than in patients with type 2 diabetes mellitus and no symptoms of depression (82.6±16.1. Vs 122± 17.47, p˂ 0.001). There was a statistically significant difference in BDNF levels in patients with diabetes among the three genotypes of the BDNF gene (p-value < 0.001). Val/ Val carriers had the highest serum BDNF levels, and Met/ Met carriers had the lowest serum BDNF levels. Subgroup analysis showed statistically significant genotype-related differences in serum BDNF levels among the three subgroups in the Depression group. Val/ Val carriers had the highest serum BDNF levels, and Met/ Met carriers had the lowest serum BDNF levels. BDNF Val66Met polymorphism had no significant association with the presence of depression, yet there was a trend towards significance (p = 0.05) Conclusion: In this pilot, Low levels of BDNF were associated with depression in patients with type 2 diabetes. Carriers of the Met/ Met allele have the lowest serum BDNF levels. Multicenter studies with more participants are required.

Brain-derived neurotrophic factor interplay with oxidative stress: neuropathology approach in potential biomarker of Alzheimer's disease

The aging population poses a serious challenge concerning an increased prevalence of Alzheimer's disease (AD) and its impact on global burden, morbidity, and mortality. Oxidative stress, as a molecular hallmark that causes susceptibility in AD, interplays to other AD-related neuropathology cascades and decreases the expression of central and circulation brain-derived neurotrophic factor (BDNF), an essential neurotrophin that serves as nerve development and survival, and synaptic plasticity in AD. By its significant correlation with the molecular and clinical progression of AD, BDNF can potentially be used as an objectively accurate biomarker for AD diagnosis and progressivity follow-up in future clinical practice. This comprehensive review highlights the oxidative stress interplay with BDNF in AD neuropathology and its potential use as an AD biomarker.

The effects of curcumin on Brain-Derived Neurotrophic Factor expression in neurodegenerative disorders

Brain-Derived Neurotrophic Factor (BDNF) is a crucial molecule implicated in plastic modifications related to learning and memory. The expression of BDNF is highly regulated, which can lead to significant variability in BDNF levels in healthy subjects. Changes in BDNF expression might be associated with neuropsychiatric diseases, particularly in structures important for memory processes, including the hippocampus and parahippocampal areas. Curcumin is a natural polyphenolic compound that has great potential for the prevention and treatment of age-related disorders by regulating and activating the expression of neural protective proteins such as BDNF. This review discusses and analyzes the available scientific literature on the effects of curcumin on BDNF production and function in both in vitro and in vivo models of disease.

Brain-Derived Neurotrophic Factor Val66Met Genotype Modulates Latent Inhibition: Relevance for Schizophrenia

BACKGROUND AND HYPOTHESIS

Latent inhibition (LI) is a measure of selective attention and learning relevant to Schizophrenia (SZ), with 2 abnormality poles: Disrupted LI in acute SZ, thought to underlie positive symptoms, and persistent LI (PLI) in schizotypy and chronic SZ under conditions where normal participants fail to show LI. We hypothesized that Brain-Derived Neurotrophic Factor (BDNF)-Met genotype shifts LI toward the PLI pole.

STUDY DESIGN

We investigated the role of BDNF-Val66Met polymorphism and neural activation in regions involved in LI in mice, and the interaction between the BDNF and CHL1, a gene associated with SZ.

STUDY RESULTS

No LI differences occurred between BDNF-wild-type (WT) (Val/Val) and knock-in (KI) (Met/Met) mice after weak conditioning. Chronic stress or stronger conditioning disrupted LI in WT but not KI mice. Behavior correlated with activation in infralimbic and orbitofrontal cortices, and nucleus accumbens. Examination of LI in CHL1-KO mice revealed no LI with no Met alleles (BDNF-WTs), PLI in CHL1-WT mice with 1 Met allele (BDNF-HETs), and PLI in both CHL1-WTs and CHL1-KOs with 2 Met alleles (BDNF-KIs), suggesting a shift to LI persistence with the number of BDNF-Met alleles in the CHL1 model of acute SZ.

CONCLUSIONS

Results support a role for BDNF polymorphisms in gene-gene and gene-environment interactions relevant to SZ. BDNF-Met allele may reduce expression of some acute SZ symptoms, and may increase expression of negative symptoms in individuals with chronic SZ. Evaluation of (screening for) SZ phenotypes associated with mutations at a particular locus (eg, CHL1), may be masked by strong effects at different loci (eg, BDNF).

The mechanism of human neural stem cell secretomes improves neuropathic pain and locomotor function in spinal cord injury rat models: through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities

Background

Globally, spinal cord injury (SCI) results in a big burden, including 90% suffering permanent disability, and 60%-69% experiencing neuropathic pain. The main causes are oxidative stress, inflammation, and degeneration. The efficacy of the stem cell secretome is promising, but the role of human neural stem cell (HNSC)-secretome in neuropathic pain is unclear. This study evaluated how the mechanism of HNSC-secretome improves neuropathic pain and locomotor function in SCI rat models through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities.

Methods

A proper experimental study investigated 15 Rattus norvegicus divided into normal, control, and treatment groups (30 μL HNSC-secretome, intrathecal in the level of T10, three days post-traumatic SCI). Twenty-eight days post-injury, specimens were collected, and matrix metalloproteinase (MMP)-9, F2-Isoprostanes, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β, and brain derived neurotrophic factor (BDNF) were analyzed. Locomotor recovery was evaluated via Basso, Beattie, and Bresnahan scores. Neuropathic pain was evaluated using the Rat Grimace Scale.

Results

The HNSC-secretome could improve locomotor recovery and neuropathic pain, decrease F2-Isoprostane (antioxidant), decrease MMP-9 and TNF-α (anti-inflammatory), as well as modulate TGF-β and BDNF (neurotrophic factor). Moreover, HNSC-secretomes maintain the extracellular matrix of SCI by reducing the matrix degradation effect of MMP-9 and increasing the collagen formation effect of TGF-β as a resistor of glial scar formation.

Conclusions

The present study demonstrated the mechanism of HNSC-secretome in improving neuropathic pain and locomotor function in SCI through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities.

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.

Long-term nucleus basalis cholinergic depletion induces attentional deficits and impacts cortical neurons and BDNF levels without affecting the NGF synthesis

Basal forebrain cholinergic neurons (BFCNs) represent the main source of cholinergic innervation to the cortex and hippocampus and degenerate early in Alzheimer's disease (AD) progression. Phenotypic maintenance of BFCNs depends on levels of mature nerve growth factor (mNGF) and mature brain-derived neurotrophic factor (mBDNF), produced by target neurons and retrogradely transported to the cell body. Whether a reciprocal interaction where BFCN inputs impact neurotrophin availability and affect cortical neuronal markers is unknown. To address our hypothesis, we immunolesioned the nucleus basalis (nb), a basal forebrain cholinergic nuclei projecting mainly to the cortex, by bilateral stereotaxic injection of 192-IgG-Saporin (the cytotoxin Saporin binds p75ntr receptors expressed exclusively by BFCNs) in 2.5-month-old Wistar rats. At six months post-lesion, Saporin-injected rats (SAP) showed an impairment in a modified version of the 5-Choice Serial Reaction Time Task (5-choice task). Post-mortem analyses of the brain revealed a reduction of Choline Acetyltransferase-immunoreactive neurons compared to wild-type controls. A diminished number of cortical vesicular acetylcholine transporter-immunoreactive boutons was accompanied by a reduction in BDNF mRNA, mBDNF protein levels, markers of glutamatergic (vGluT1) and GABAergic (GAD65) neurons in the SAP-group compared to the controls. NGF mRNA, NGF precursor and mNGF protein levels were not affected. Additionally, cholinergic markers correlated with the attentional deficit and BDNF levels. Our findings demonstrate that while cholinergic nb loss impairs cognition and reduces cortical neuron markers, it produces differential effects on neurotrophin availability, affecting BDNF but not NGF levels.

The ability of orexin-A to modify pain-induced cyclooxygenase-2 and brain-derived neurotrophic factor expression is associated with its ability to inhibit capsaicin-induced pulpal nociception in rats

Background

The rostral ventromedial medulla (RVM) is a critical region for the management of nociception. The RVM is also involved in learning and memory processes due to its relationship with the hippocampus. The purpose of the present study was to investigate the molecular mechanisms behind orexin-A signaling in the RVM and hippocampus’s effects on capsaicin-induced pulpal nociception and cognitive impairments in rats.

Methods

Capsaicin (100 g) was applied intradentally to male Wistar rats to induce inflammatory pulpal nociception. Orexin-A and an orexin-1 receptor antagonist (SB-334867) were then microinjected into the RVM. Immunoblotting and immunofluorescence staining were used to check the levels of cyclooxygenase-2 (COX-2) and brain-derived neurotrophic factor (BDNF) in the RVM and hippocampus.

Results

Interdental capsaicin treatment resulted in nociceptive responses as well as a reduction in spatial learning and memory. Additionally, it resulted in decreased BDNF and increased COX-2 expression levels. Orexin-A administration (50 pmol/1 μL/rat) could reverse such molecular changes. SB-334867 microinjection (80 nM/1 μL/rat) suppressed orexin’s effects.

Conclusions

Orexin-A signaling in the RVM and hippocampus modulates capsaicin-induced pulpal nociception in male rats by increasing BDNF expression and decreasing COX-2 expression.

Anatomical differences in nociceptor neurons sensitivity

Background

Dorsal Root Ganglia (DRG) neurons are derived from the neural crest and mainly innervate the skin, while Jugular Nodose Complex (JNC) neurons originate from the placode and innervate internal organs. These ganglia are composed of highly heterogeneous groups of neurons aimed at assessing and preserving homeostasis. Among other subtypes, nociceptor neurons are specialized in sensing and responding to environmental dangers. As form typically follows function, we hypothesized that JNC and DRG neurons would be phenotypically and transcriptomically different.

Methods

Mouse JNC and DRG neurons were cultured ex vivo. Using calcium imaging, qPCR and neurite outgrowth assay, we compared the sensitivity of JNC and DRG neurons. Using in-silico analysis of existing RNA sequencing datasets, we confronted our results to transcriptomic differences found between both ganglia.

Results

We found drastically different expression levels of Transient Receptor Potential (TRP) channels, growth factor receptors and neuropeptides in JNC and DRG neurons. Functionally, naïve JNC neurons’ TRP channels are more sensitive to thermal cues than the ones from DRG neurons. However, DRG neurons showed increased TRP channel responsiveness, neuropeptide release and neurite outgrowth when exposed to Nerve Growth Factor (NGF). In contrast, JNC neurons preferentially responded to Brain-derived neurotrophic factor (BDNF).

Conclusion

Our data show that JNC and DRG neurons are transcriptomically and functionally unique and that pain sensitivity is different across anatomical sites. Drugs targeting NGF signaling may have limited efficacy to treat visceral pain. Bioelectronics nerve stimulation should also be adjusted to the ganglia being targeted and their different expression profile.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42234-022-00088-w.

Effect of providing purple sweet potato water extract on tumor necrosis factor-α levels, protein 53 expression, glial fibrillary acidic protein expression, brain-derived neurotrophic factor levels, and spatial working memory in rats with d-galactose induction

Alzheimer's dementia (AD) is a neurodegenerative disease. The mechanism of oxidative stress in AD is due to amyloid beta (Aβ) protein that aggregates to form plaques, which further triggers chronic inflammation and neuronal apoptosis. Purple sweet potato extract with the main content of anthocyanins is a potential antioxidant with a direct target on the amyloid cascade hypothesis.

Objective

The research objective was to determine the role of purple sweet potato water extract as an antioxidant and anti-inflammatory in preventing apoptosis in order to provide a neuroprotective effect in d-galactose-induced rats.

Methods

A total of 100 male Wistar rats with randomized posttest-only control group design that met the eligibility criteria were included in this study. The treatment group was given 200 mg/kg BW/day of purple sweet potato water extract on days 1-70. d-galactose induction was administered in the treatment and control groups on days 15-70.

Results

The independent t-test showed that the mean tumor necrosis factor-α (TNF-α) levels in the treatment group (735.36±139.74) was significantly lower than that in the control group (896.77±152.52). The p53 and glial fibrillary acidic protein (GFAP) expressions of astrocyte cells in the treatment group were significantly lower than that in the control group. The brain-derived neurotrophic factor (BDNF) levels in the treatment group (498.13±121.47) were higher than that in the control (391.93±140.28), and there was a significant increase in spatial working memory in the treatment group (72.01±10.22) than the control (59.77±11.87).

Conclusions

The neuroprotective effect of purple sweet potato extract is due to d-galactose induction resulting from decrease in TNF-α levels, p53 expression, and GFAP expression and increase in BDNF levels and spatial working memory.

Sex differences in risk behavior parameters in adolescent mice: Relationship with brain-derived neurotrophic factor in the medial prefrontal cortex

Adolescence is as a period of development characterized by impulsive and risk-seeking behaviors. Risk behaviors (RB) involves exposure to dangerous or negative consequences to achieve goal-directed behaviors, such as reward-seeking. On the other hand, risk aversion/assessment behaviors allow the individual to gather information or avoid potentially threatening situations. Evidence has suggested that both behavioral processes, RB and risk assessment (RA), may have sex-differences. However, sex-specific behavioral patterns implicated in RB and RA are not fully understood. To address that, we investigated sex differences in risk-behavioral parameters in a decision-making task developed for rodents. In addition, we investigated the potential role of sex-dependent differences in gene expression of brain-derived neurotrophic factor (BDNF) exon IV in the medial prefrontal cortex (mPFC), which has been implicated to mediate PFC-related behavioral dysfunctions. Male and female C57BL/6J adolescent mice were evaluated in the elevated plus-maze (EPM) to assess anxiety-like behaviors and in the predator-odor risk taking (PORT) task. The PORT task is a decision-making paradigm in which a conflict between the motivation towards reward pursuit and the threat elicited by predatory olfactory cues (coyote urine) is explored. After behavioral testing, animals were euthanized and BDNF exon IV gene expression was measured by RT-qPCR. Comparative and correlational analyses for behavioral and molecular parameters were performed for both sexes. We observed that female mice spent more time exploring the middle chamber of the PORT apparatus in the aversive condition, which is an indicative of avoidance behavior. Female mice also had a higher latency to collect the reward than male mice and presented less time exploring the open arms of the EPM. BDNF exon IV gene expression was higher among females, and there was a positive correlation between the BDNF and PORT behavioral parameters. Our findings suggest sex-dependent effects in the PORT task. Females presented higher RA and avoidance behavior profile and expressed higher levels of BDNF exon IV in the mPFC. Moreover, higher BDNF expression was correlated with RA behaviors, which suggests that adolescent females tend to evaluate the risks more than adolescent males and that BDNF gene expression may be mediating decision-making processes.

Investigating Predictive Factors of Suicidal Re-attempts in Adolescents and Young Adults After a First Suicide Attempt, a Prospective Cohort Study. Study Protocol of the SURAYA Project

INTRODUCTION

Suicide is the fourth leading cause of death in youth. Previous suicide attempts are among the strongest predictors of future suicide re-attempt. However, the lack of data and understanding of suicidal re-attempt behaviors in this population makes suicide risk assessment complex and challenging in clinical practice. The primary objective of this study is to determine the rate of suicide re-attempts in youth admitted to the emergency department after a first suicide attempt. The secondary objectives are to explore the clinical, socio-demographic, and biological risk factors that may be associated with re-attempted suicide in adolescents and young adults.

METHODS

We have developed a single-center prospective and naturalistic study that will follow a cohort of 200 young people aged 16 to 25 years admitted for a first suicide attempt to the emergency department of Lyon, France. The primary outcome measure will be the incidence rate of new suicide attempts during 3 months of follow-up. Secondary outcomes to investigate predictors of suicide attempts will include several socio-demographic, clinical and biological assessments: blood and hair cortisol levels, plasma pro- and mature Brain-Derived Neurotrophic Factor (BDNF) isoforms proportion, previous infection with toxoplasma gondii, and C-Reactive Protein (CRP), orosomucoid, fibrinogen, interleukin (IL)-6 inflammatory markers.

DISCUSSION

To our knowledge, the present study is the first prospective study specifically designed to assess the risk of re-attempting suicide and to investigate the multidimensional predictive factors associated with re-attempting suicide in youth after a first suicide attempt. The results of this study will provide a unique opportunity to better understand whether youth are an at-risk group for suicide re-attempts, and will help us identify predictive factors of suicide re-attempt risk that could be translated into clinical settings to improve psychiatric care in this population.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier: NCT03538197, first registered on 05/29/2018. The first patient was enrolled 05/22/2018.

LncPVT1 regulates osteogenic differentiation of human periodontal ligament cells via miR-10a-5p/brain-derived neurotrophic factor

BACKGROUND

Identifying the factors affecting osteoblast differentiation ofperiodontal ligamentcells (PDLCs) can help enhance the regeneration of periodontal tissue.LncRNAplasmacytoma variant translocation 1 (lncPVT1) is an important regulatory factor involved in many biological processes, but its role in osteogenesisremains unclear.

METHODS

Expressionsof osteogenic markers were detected by quantitative reverse transcription polymerase chain reaction and Western blot analysis. Alkaline phosphatase staining was conducted for early osteoblast differentiation and alizarin red S staining was used for mineral deposition. RNA sequencing was used to identify the miRNAs regulated by lncPVT1 during osteogenesis. Cell transfection was used to overexpress or knockdown lncPVT1 and miR-10a-5p. Dual luciferase reporter assayswere conducted to analyze the binding of miR-10a-5p to brain-derived neurotrophic factor (BDNF).

RESULTS

LncPVT1 was significantly increased during osteogenic induction of PDLCs. Overexpression of lncPVT1 promoted osteogenesis, whereas lncPVT1 knockdown inhibited this process. RNA sequencing showed that miR-10a-5p expression was significantly increased after lncPVT1 knockdown.RNA immunoprecipitation assay further demonstrated the binding potential of lncPVT1 and miR-10a-5p. MiR-10a-5p inhibited the osteogenesis of PDLCs, and partially reversed the stimulatory effects of lncPVT1.Subsequently, we identified a predicted binding site for miR-10a-5p on BDNF and confirmed it using dual luciferase reporter assays. Moreover, lncPVT1 upregulated the expression of BDNF, while miR-10a-5p downregulated BDNF expression. BDNF promoted osteogenesis and partially rescued the si-lncPVT1-mediated inhibition of PDLCs osteogenic differentiation.

CONCLUSION

LncPVT1 positively regulated the osteogenic differentiation of PDLCs via miR-10a-5p and BDNF.Our resultsprovide a promising target for enhancing the osteogenic potential of PDLCs. This article is protected by copyright. All rights reserved.

Endogenous Deficiency of Brain-Derived Neurotrophic Factor Induces the Downregulation of Tryptophan Hydroxylase-2 Expression in Raphe Nuclei of Rapid Ejaculator Rats

BACKGROUND

Premature ejaculation (PE) is one of the most common ejaculatory disorders. Recent studies have suggested a close relationship between the serotonin (5-hydroxytryptamine [5-HT]) system and brain-derived neurotrophic factor (BDNF), raising the question of whether BDNF plays a role in ejaculation regulation. To our knowledge, no previous studies have explored BDNF level of the central nervous system in ejaculatory disorders. At the same time, the interaction of central BDNF and 5-HT systems has not been undertaken in ejaculation regulation field.

AIM

The aim of this study was to investigate the interaction between BDNF and 5-HT levels in raphe nuclei which contains the serotonergic neurons in a rat animal model with different ejaculatory behavior.

METHODS

Eighteen male rats were selected and classified as "sluggish," "normal," and "rapid" ejaculators on the basis of ejaculation frequency during copulatory behavioral testing. BDNF and 5-HT levels were determined by enzyme-linked immunosorbent assay (ELISA). Real-Time Quantitative PCR and Western blot analyses were used to measure the mRNA level of Tryptophan Hydroxylase-2 (TPH2) gene and the expression of TPH2 protein (the rate-limiting enzyme in central 5-HT synthesis) in raphe nuclei, respectively.

OUTCOMES

Male rat sexual behavior, the levels of BDNF and 5-HT in raphe nuclei of rats with different ejaculatory behavior, the mRNA level of gene encoding TPH2 and the expression of TPH2 protein in raphe nuclei.

RESULTS

The primary finding of our study was that BDNF concentration was significantly decreased in raphe nuclei of rapid ejaculators. There was a strong positive correlation between the levels of BDNF and 5-HT (r = 0.944, P < .001). Further results showed that decreased TPH2 gene expression accompanied by TPH2 protein was shown in rapid ejaculators with lower BDNF level.

CLINICAL IMPLICATIONS

With refinement of current knowledge, BDNF may eventually serve as a promising biomarker in patients with PE.

STRENGTHS & LIMITATIONS

There are no previous studies examining the interaction of the brain BDNF and 5-HT in ejaculation regulation field. The main limitation is the limited sample size.

CONCLUSION

BDNF may act via increasing the synthesis of central 5-HT in the process of ejaculation regulation. Our results suggest lack of endogenous BDNF induces the downregulation of TPH2 gene expression and the decrease of 5-HT synthesis in raphe nuclei of rapid ejaculator rats.

Berberine and Ginsenoside Rb1 Ameliorate Depression-Like Behavior in Diabetic Rats

Rhizoma coptidis (Huang-lian) and Asian ginseng have been widely used in the treatment of diabetes and other concurrent diseases with apparent effects. This study investigated the effects of the active ingredients of R. coptidis and ginseng, berberine and ginsenoside Rb1, on depression-like behavior in a rat diabetes model. The animal model was established via a high-fat diet and intraperitoneal injection of streptozotocin, while the animal's depression-like behavior was induced via chronic unpredictable mild stress. These experimental rats were divided into four groups: control, depression-like behavior (DLB), metformin plus fluoxetine hydrochloride (M+FH), and berberine plus ginsenoside Rb1 (B+GRb1) groups. Glucose metabolism and insulin resistance were evaluated by oral glucose test and glucose clamp study. Depression-like behavior was evaluated via behavioral analyses, including forced swim, sucrose preference, elevated plus maze, and open-field tests. HE and Nissl staining, plasma cortisol expression of adrenocorticotropic hormone, and brain-derived neurotrophic factor (BDNF) levels were assayed to explore the mechanisms of action. Compared with the control, rats in the DLB group had a significant increase in the levels of blood glucose and depression-like behavior. The B+GRb1 group significantly improved glucose metabolism and insulin resistance, reduced depression-like behavior, downregulated levels of plasma cortisol and adrenocorticotropic hormone under stress, and upregulated BDNF protein expression compared to the DLB rats. HE and Nissl staining data revealed that B+GRb1 protected neurons from pathological and morphological changes. Thus, berberine and ginsenoside Rb1 not only improved glucose metabolism in diabetic rats but also ameliorated their depression-like behavior under chronic unpredictable stress. Mechanistically, studied data with plasma hormonal levels and brain neuronal pathological/morphological changes supported the observed effects. The combination of berberine and ginsenoside Rb1 may have a clinical value in the management of diabetic patients with depression.

Assessing Pain Behavioral Responses and Neurotrophic Factors in the Dorsal Root Ganglion, Serum and Peritoneal Fluid in Rat Models of Endometriosis

Objective: Pain is the most frequently reported symptom involving in endometriosis. The alterations of neurotrophic factors and certain neuropeptides in the dorsal root ganglion (DRG), as well as serum and peritoneal fluid (PF), were evaluated in rat models of endometriosis.

Materials and methods: Twenty-four Sprague Dawley female rats were selected and maintained in a standard condition with 12 hours’ dark-light cycles. All the rats were randomly assigned to 3 groups: Control (intact rats); Sham (the operation was conducted without endometriosis induction); and Endometriosis (endometriosis induction was performed). The formalin test was performed for all groups on the first and the 21^st day of the study. The assessments of Brain-Derived Neurotrophic Factor (BDNF), Nerve Growth Factor (NGF), Calcitonin Gene-Related Peptide (CGRP), and Substance P levels were carried out by enzyme-linked immunosorbent assay (Elisa). The data were analyzed by One-Way ANOVA. The Tukey’s test was used as post-hoc.

Results: Endometriosis induction significantly increased the mean pain scores in the endometriosis group in all three phases of the formalin test. The concentrations of DRG-CGRP (p=0.035), BDNF (p<0.001), and NGF (p=0.006) in the endometriosis group were significantly higher than that of the other groups while serum-BDNF (p<0.001), Substance P (p=0.009), and NGF (p=0.015) were significantly lower in endometriosis group compared to other groups. The concentrations of PF-BDNF (p=0.025) and Substance P (p=0.009) were significantly lower than those of other groups.

Conclusion: The present results delineate that endometriosis induction could lead to hyperalgesia. This may be related to the significant increases in the BDNF, NGF, and CGRP in DRG.

Brain-derived neurotrophic factor (BDNF) levels in first-episode schizophrenia and healthy controls: A comparative study

BACKGROUND

Abnormalities in brain development and plasticity have been associated with the pathophysiology of schizophrenia. The role of brain-derived neurotrophic factor (BDNF) in schizophrenia is the recent area of interest because it regulates neurogenesis. The current study aimed to assess and compare serum BDNF levels between first-episode schizophrenia patients and healthy controls, and evaluate its correlation with the socio-demographic and clinical variables.

METHODOLOGY

It was a cross-sectional comparative study for the assessment of serum BDNF levels between patients with first-episode schizophrenia (N=50) and healthy controls (N-50) conducted in the Department of Psychiatry at a tertiary care public hospital attached to a medical school in North India. Participants were assessed for the socio-demographic parameters, nicotine dependence, and clinical details using structured scales. Serum BDNF level estimated using the sandwich ELISA technique. The comparison between the groups was done by using a Student t-test or chi-square test. Spearman correlation was performed between mean BDNF scores and demographic or illness variables in both first-episode schizophrenia and healthy control groups.

RESULTS

There was a significantly lower mean score of total serum BDNF levels in first-episode schizophrenia patients as compared to controls (8.44 ± 1.54 vs 10.44 ± 2.04; t = 5.52, p < 0.001; 95% CI = 1.28-2.71). The total FTND scores for smokeless tobacco use were negatively correlated to BDNF levels among healthy controls (r=-0.30, p=0.03) as well as in the first-episode schizophrenia group (r=-0.32, p= 0.04). None of the other illness-related variables were correlated to serum BDNF values in the first episode schizophrenia group.

CONCLUSION

Individuals with first-episode schizophrenia have lower serum BDNF levels than healthy controls. The illness-related factors such as duration of untreated psychosis or psychopathology were not correlated with BDNF levels. Thus abnormal signaling of BDNF can lead to abnormal brain functioning which can make an individual more susceptible to schizophrenia.

Exploring the role and mechanisms of diallyl trisulfide and diallyl disulfide in chronic constriction-induced neuropathic pain in rats

Background

Garlic oil is a rich source of organosulfur compounds including diallyl disulfide and diallyl trisulfide. There have been studies showing the neuroprotective actions of these organosulfur compounds. However, the potential of these organosulfur compounds in neuropathic pain has not been explored. The present study was aimed at investigating the pain attenuating potential of diallyl disulfide and diallyl trisulfide in chronic constriction injury (CCI)-induced neuropathic pain in rats. The study also explored their pain-attenuating mechanisms through modulation of H₂S, brain-derived neurotrophin factor (BDNF) and nuclear factor erythroid 2-related factor 2 (Nrf2).

Methods

The rats were subjected to CCI injury by ligating the sciatic nerve in four places. The development of neuropathic pain was measured by assessing mechanical hyperalgesia (Randall–Selittotest), mechanical allodynia (Von Frey test), and cold allodynia (acetone drop test) on 14th day after surgery.

Results

Administration of diallyl disulfide (25 and 50 mg/kg) and diallyl trisulfide (20 and 40 mg/kg) for 14 days led to a significant reduction in pain in CCI-subjected rats. Moreover, treatment with these organosulfur compounds led to the restoration of H₂S, BDNF and Nrf2 levels in the sciatic nerve and dorsal root ganglia. Co-administration of ANA-12 (BDNF blocker) abolished pain attenuating actions as well as BDNF and the Nrf2 restorative actions of diallyl disulfide and diallyl trisulfide, without modulating H₂S levels.

Conclusions

Diallyl disulfide and diallyl trisulfide have the potential to attenuate neuropathic pain in CCI-subjected rats possibly through activation of H₂S-BDNF-Nrf2 signaling pathway.

Physical Exercise Increased Brain-Derived Neurotrophic Factor in Elderly Population with Depression

BACKGROUND

Depression is very common in the elderly population. Physical exercise is one of the non-pharmacological procedures that promise to be a solution to improve the severity of depression. Brain-Derived Neurotrophic Factor (BDNF) plays a role in maintaining the survival of neuronal cells and in the regulation of synapse plasticity, affecting serotonin production in the hippocampus and thus the depressive symptoms.

AIM

This study aimed to assess the role of physical exercise in affecting BDNF levels in elderly with depression.

METHODS

Thirty-five elderly women (age ≥ 50 years) with depressive episodes based on Diagnostic and Statistical Manual of Mental Disorders (DSM)-V criteria were enrolled as treatment group, and 35 elderly women without depressive episodes were enrolled as control group, and underwent physical exercise in the form of treadmill with a speed of 6 km/h for 15 minutes. Physical exercise was carried out once a day for 28 days. As much as 1 ml of blood from the study, subjects were obtained from the cubital vein before the exercise commenced. Brain-Derived Neurotrophic Factor (BDNF) serum level was assessed by Enzyme-Linked Immunosorbent Assay (ELISA). Data were presented in the form of mean ± SD. An independent T-test was used to test levels after exercise in the depression group compared to the non-depression group.

RESULTS

Pre-exercise BDNF levels in the depression group were lower than the group of elderly without depression. Physical exercise increased BDNF production in both elderly groups with and without depression. In the depression group, the increasing percentage of BDNF level was higher compared to non-depressive elderly.

CONCLUSION

The increasing percentage of BDNF level was found to be higher in depressive elderly performing physical exercise. Physical exercise may be beneficial in supporting the therapy of elderly with depression.

Plasma Brain-Derived Neurotrophic Factor (BDNF) and serum cortisol levels in a sample of workers exposed to occupational stress and suffering from Adjustment Disorders

INTRODUCTION

Decreased plasma BDNF (pBDNF) levels have been proposed as a biomarker in illness phases of mood disorders. Serum cortisol (seC) levels are an index of energy mobilization and stress. The aim of this cross-sectional study was to evaluate pBDNF and seC levels in workers exposed to occupational stress and suffering from Adjustment Disorders (AD) compared to healthy workers.

METHODS

Plasma BDNF and seC levels were measured by means of specific immunoassays in 64 AD patients and 38 healthy controls. Perceived and occupational stress was evaluated in patients and controls using the Psychological Stress Measure (PSM) and the Job Content Questionnaire (JCQ). Psychopatological symptoms in patients were assessed using specific rating scales.

RESULTS

Plasma BDNF levels resulted significantly higher in patients than in controls, whereas no significant differences were found for seC levels. In patients but not in controls pBDNF levels showed a significant positive correlation with seC levels. Perceived stress levels were positively correlated with all psychopatological rating scales scores.

CONCLUSIONS

BDNF could play a key role in the pathophysiology of stress-related disorders and its peripheral levels elevation could contribute to protect neurons under stress. Further research is needed focusing on biomarkers for stress-related disorders as a potential tool for the diagnosis and prevention of occupational diseases.

The Impact of Physical Exercise on Brain-Derived Neurotrophic Factor (BDNF) Level in Elderly Population

BACKGROUND

Memory function disorder is a major health problem in geriatric patients. Physical exercise has the potency to decrease the incidence of many degenerative and chronic health problem, related to cognitive deterioration (dementia).

AIM

This research aimed to observe the effect of physical exercise in various doses and duration on memory function by analysing the role of Brain-Derived Neurotrophic Factor (BDNF) as a regulatory protein affected by exercise.

METHODS

This was an analytical observational study with a cohort design. Thirty participants were included in each group, classified as exercise and non-exercise group. The exercise was in the form of jogging for at least fifteen minutes every day. The observation was done for sixty days. Cognitive function assessment was done by using the Mini-Mental State Examination (MMSE) questionnaire. Meanwhile, the BDNF level was assessed by ELISA. Statistical analysis was done using Independent T-test.

RESULTS

Exercise group showed better MMSE score (28.56 ± 1.76), and a higher concentration of BDNF (235.34 ± 12.56 pg/mL), both were statistically significant.

CONCLUSION

Physical exercise was able to maintain geriatric cognitive function performance by BDNF protein regulation.

Effects of Risperidone and Paliperidone on Brain-Derived Neurotrophic Factor and N400 in First-Episode Schizophrenia

Background:

Risperidone and paliperidone have been the mainstay treatment for schizophrenia and their potential role in neuroprotection could be associated with brain-derived neurotrophic factor (BDNF) and N400 (an event-related brain potential component). So far, different effects on both BDNF and N400 were reported in relation to various antipsychotic treatments. However, few studies have been conducted on the mechanism of risperidone and paliperidone on BDNF and N400. This study aimed to compare the effects of risperidone and paliperidone on BDNF and the N400 component of the event-related brain potential in patients with first-episode schizophrenia.

Methods:

Ninety-eight patients with first-episode schizophrenia were randomly divided into the risperidone and paliperidone groups and treated with risperidone and paliperidone, respectively, for 12 weeks. Serum BDNF level, the latency, and amplitude of the N400 event-related potential before and after the treatment and Positive and Negative Syndrome Scale (PANSS) scores were compared between the two groups.

Results:

A total of 94 patients were included in the final analysis (47 patients in each group). After the treatment, the serum BDNF levels in both groups increased (all P < 0.01), while no significant difference in serum BDNF level was found between the groups before and after the treatment (all P > 0.05). After the treatment, N400 amplitudes were increased (from 4.73 ± 2.86 μv and 4.51 ± 4.63 μv to 5.35 ± 4.18 μv and 5.52 ± 3.08 μv, respectively) under congruent condition in both risperidone and paliperidone groups (all P < 0.01). Under incongruent conditions, the N400 latencies were shortened in the paliperidone group (from 424.13 ± 110.42 ms to 4.7.41 ± 154.59 ms, P < 0.05), and the N400 amplitudes were increased in the risperidone group (from 5.80 ± 3.50 μv to 7.17 ± 5.51 μv, P < 0.01). After treatment, the total PANSS score in both groups decreased significantly (all P < 0.01), but the difference between the groups was not significant (P > 0.05). A negative correlation between the reduction rate of the PANSS score and the increase in serum BDNF level after the treatment was found in the paliperidone group but not in the risperidone group.

Conclusions:

Both risperidone and paliperidone could increase the serum BDNF levels in patients with first-episode schizophrenia and improve their cognitive function (N400 latency and amplitude), but their antipsychotic mechanisms might differ.

Glehnia littoralis Extract Promotes Neurogenesis in the Hippocampal Dentate Gyrus of the Adult Mouse through Increasing Expressions of Brain-Derived Neurotrophic Factor and Tropomyosin-Related Kinase B

Background:

Glehnia littoralis has been used for traditional Asian medicine, which has diverse therapeutic activities. However, studies regarding neurogenic effects of G. littoralis have not yet been considered. Therefore, in this study, we examined effects of G. littoralis extract on cell proliferation, neuroblast differentiation, and the maturation of newborn neurons in the hippocampus of adult mice.

Methods:

A total of 39 male ICR mice (12 weeks old) were randomly assigned to vehicle-treated and 100 and 200 mg/kg G. littoralis extract-treated groups (n = 13 in each group). Vehicle and G. littoralis extract were orally administrated for 28 days. To examine neurogenic effects of G. littoralis extract, we performed immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU, an indicator for cell proliferation) and doublecortin (DCX, an immature neuronal marker) and double immunofluorescence staining for BrdU and neuronal nuclear antigen (NeuN, a mature neuronal marker). In addition, we examined expressional changes of brain-derived neurotrophic factor (BDNF) and its major receptor tropomyosin-related kinase B (TrkB) using Western blotting analysis.

Results:

Treatment with 200 mg/kg, not 100 mg/kg, significantly increased number of BrdU-immunoreactive (⁺) and DCX⁺ cells (48.0 ± 3.1 and 72.0 ± 3.8 cells/section, respectively) in the subgranular zone (SGZ) of the dentate gyrus (DG) and BrdU⁺/NeuN⁺ cells (17.0 ± 1.5 cells/section) in the granule cell layer as well as in the SGZ. In addition, protein levels of BDNF and TrkB (about 232% and 244% of the vehicle-treated group, respectively) were significantly increased in the DG of the mice treated with 200 mg/kg of G. littoralis extract.

Conclusion:

G. littoralis extract promots cell proliferation, neuroblast differentiation, and neuronal maturation in the hippocampal DG, and neurogenic effects might be closely related to increases of BDNF and TrkB proteins by G. littoralis extract treatment.

Interaction of Brain-Derived Neurotrophic Factor Val66Met genotype and history of stress in regulation of prepulse inhibition in mice

The Brain-Derived Neurotrophic Factor (BDNF) Val66Met polymorphism results in reduced activity-dependent BDNF release and has been implicated in schizophrenia. However, effects of the polymorphism on functional dopaminergic and N-methyl-d-aspartate (NMDA) receptor-associated activity remain unclear. We used prepulse inhibition, a measure of sensorimotor gating which is disrupted in schizophrenia, and assessed the effects of acute treatment with the dopamine receptor agonist, apomorphine (APO), and the NMDA receptor antagonist, MK-801. We used adult humanized hBDNF^Val66Met 'knockin' mice which express either the Val/Val, Val/Met or Met/Met genotype. An interaction of BDNF with stress was modelled by chronic young-adult treatment with corticosterone (CORT). At 1 or 3mg/kg, APO had no effect in Val/Val mice but significantly reduced PPI at the 100ms inter-stimulus interval (ISI) in Val/Met and Met/Met mice. However, after CORT pretreatment, APO significantly reduced PPI in all genotypes similarly. At 0.1 or 0.25mg/kg, MK-801 significantly disrupted PPI at the 100ms ISI independent of genotype or CORT pretreatment. There were differential effects of APO and MK-801 on PPI at the 30ms ISI and startle between the genotypes, irrespective of CORT pretreatment. These results show that the BDNF Val66Met Val/Met and Met/Met genotypes are more sensitive than the Val/Val genotype to the effect of APO on PPI. A history of stress, here modelled by chronic CORT administration, increases effects of APO in Val/Val mice.

Brain-Derived Neurotrophic Factor as a Treatment Option for Retinal Degeneration

This review discusses the therapeutic potential of brain-derived neurotrophic factor (BDNF) for retinal degeneration. BDNF, nerve growth factor (NGF), neurotrophin 3 (NT-3) and NT-4/NT-5 belong to the neurotrophin family. These neuronal modulators activate a common receptor and a specific tropomyosin-related kinase (Trk) receptor. BDNF was identified as a photoreceptor protectant in models of retinal degeneration as early as 1992. However, development of effective therapeutics that exploit this pathway has been difficult due to challenges in sustaining therapeutic levels in the retina.

The Mammalian Circadian Clock Exhibits Chronic Ethanol Tolerance and Withdrawal-Induced Glutamate Hypersensitivity, Accompanied by Changes in Glutamate and TrkB Receptor Proteins

BACKGROUND

Alcohol tolerance and withdrawal-induced effects are criteria for alcohol use disorders listed by the DSM-V. Although tolerance and withdrawal have been studied over many decades, there is still uncertainty regarding mechanistic distinctions that characterize these different forms of ethanol (EtOH)-induced plasticity. Previously, we demonstrated that the suprachiasmatic nucleus (SCN) circadian clock develops both acute and rapid tolerance to EtOH inhibition of glutamate-induced circadian phase shifts. Here, we demonstrate that chronic EtOH tolerance and withdrawal-induced glutamate hypersensitivity occur in vitro and that rapid tolerance, chronic tolerance, and glutamate hypersensitivity have distinct cellular changes.

METHODS

We use single-unit extracellular electrophysiological recordings to determine whether chronic tolerance to EtOH inhibition of glutamatergic phase shifts and withdrawal-induced glutamate hypersensitivity develop in the SCN. We use Western blotting to compare phosphorylation state and total expression of N-methyl-D-aspartate (NMDA) receptor subunits and associated proteins in the SCN after mice were exposed to varying EtOH consumption paradigms.

RESULTS

Chronic tolerance developed after a minimum of 8 days of 4 h/d EtOH access, as indicated by a decreased sensitivity to EtOH inhibition of glutamate-induced phase shifts. We also observed an increased sensitivity to glutamate-induced phase shifts in SCN tissue following withdrawal. We demonstrated an increase in the ratio of NR2B:NR2A NMDA receptor subunit expression after 21 days, but not after 10 days of EtOH drinking. This increase persisted during EtOH withdrawal, along with an increase in NR2B Y1472 phosphorylation, mature brain-derived neurotrophic factor, and phosphorylated TrkB.

CONCLUSIONS

These results demonstrate that multiple tolerance forms and withdrawal-induced glutamate hypersensitivity occur in the SCN and that these different forms of EtOH-induced plasticity are accompanied by distinct changes in cellular physiology. Importantly, this study further demonstrates the power of using the SCN as a model system to investigate EtOH-induced plasticity.

The Impact of the Brain-Derived Neurotrophic Factor Gene on Trauma and Spatial Processing

The influence of genes and the environment on the development of Post-Traumatic Stress Disorder (PTSD) continues to motivate neuropsychological research, with one consistent focus being the Brain-Derived Neurotrophic Factor (BDNF) gene, given its impact on the integrity of the hippocampal memory system. Research into human navigation also considers the BDNF gene in relation to hippocampal dependent spatial processing. This speculative paper brings together trauma and spatial processing for the first time and presents exploratory research into their interactions with BDNF. We propose that quantifying the impact of BDNF on trauma and spatial processing is critical and may well explain individual differences in clinical trauma treatment outcomes and in navigation performance. Research has already shown that the BDNF gene influences PTSD severity and prevalence as well as navigation behaviour. However, more data are required to demonstrate the precise hippocampal dependent processing mechanisms behind these influences in different populations and environmental conditions. This paper provides insight from recent studies and calls for further research into the relationship between allocentric processing, trauma processing and BDNF. We argue that research into these neural mechanisms could transform PTSD clinical practice and professional support for individuals in trauma-exposing occupations such as emergency response, law enforcement and the military.

Determinants of Blood Brain-Derived Neurotrophic Factor Blood Levels in Patients with Alcohol Use Disorder

BACKGROUND

Blood brain-derived neurotrophic factor (BDNF) levels are influenced by both addiction and mood disorders, as well as somatic conditions, gender, and genetic polymorphisms, leading to widely varying results. Depressive symptoms and episodes are frequently observed in patients with alcohol use disorder, and vary widely over time, making it a challenge to determine which aspects are specifically involved in variations of serum BDNF levels in this population.

METHODS

We assessed 227 patients with alcohol dependence involved in a detoxification program, at baseline and after a follow-up of 6 months, for the Alcohol Use Disorders Identification Test score, the length of alcohol dependence, and the number of past detoxification programs. The Beck Depression Inventory and information on current tobacco and alcohol use, suicidal ideation, body mass index, age, gender, and psychotropic treatments were also collected. Serum BDNF (ELISA) and 2 genetic polymorphisms of the BDNF gene (Val33Met and rs962369) were analyzed.

RESULTS

The presence of the Met allele, 2 markers of the history of alcohol dependence (gamma glutamyl transferase and the number of past treatments in detoxification programs), and the presence of a depressive episode (but not depressive score) were significantly associated with the 2 blood levels of BDNF at baseline and after 6 months. After controlling for baseline BDNF levels, the presence of the Met allele and an ongoing depressive episode were the only variables associated with changes in BNDF levels after 6 months.

CONCLUSIONS

Low serum BDNF levels are associated with characteristics related to alcohol consumption and mood disorders, and variants of the BDNF gene in alcohol use disorder patients. The factors that most strongly influenced changes in serum BDNF levels following treatment in an alcohol detoxification program were variants of the BDNF gene and ongoing depression.

Effects of Polysaccharide of Gastrodia Elata Blume and Electro-Acupuncture on Expressions of Brain-Derived Neurotrophic Factor and Stem Cell Factor Protein in Caudate Putamen of Focal Cerebral Ischemia Rats

Background

The aim of this study was to explore the neural protective effect of polysaccharide of Gastrodia elata Blume (PGB) and electro-acupuncture (EA) on focal cerebral ischemia rats.

Material/Methods

A total of 40 Sprague-Dawley rats were randomly divided into 5 groups (normal group, model group, PGB group, EA group and PGB+EA group). The model was prepared by middle cerebral artery occlusion (MCAO). Two week after modeling, rats were given PGB, EA, or a combination of the 2 in continuous treatment for 2 successive weeks. 14 days after modeling, expressions of BDNF and SCF protein in the caudate putamen (CPu) were detected by immunohistochemistry.

Results

Positive expression of BDNF and SCF protein was found in the right caudate putamen of each group of rats. Expressions of BDNF and SCF in the CPu of the model group were higher than normal group (P<0.05). Compared with the model group, the expressions of BDNF and SCF in the CPu of the PGB group, the EA group, and the PGB plus EA group increased significantly (P<0.05). The expressions of BDNF and SCF obviously increased in the PGB plus EA group compared to those of the EA group and the PGB group (P<0.05).

Conclusions

PGB and EA up-regulated the expressions of BDNF and SCF protein in the CPu of focal cerebral ischemia rats, and the combination of PGB+EA has a synergistic effect on the recovery from cerebral ischemia.

The Effect of Preventive, Therapeutic and Protective Exercises on Hippocampal Memory Mediators in Stressed Rats

BACKGROUND

Exercise plays a significant role in learning and memory. The present study focuses on the hippocampal corticosterone (CORT), interleukin-1 beta (IL-1β), glucose, and brain-derived neurotrophic factor (BDNF) levels in preventive, therapeutic, and protective exercises in stressful conditions.

METHODS

Forty male rats were randomly divided into four groups: the control group and the preventive, therapeutic, and protective exercise groups. The treadmill running was applied at a speed of 20-21m/min and a chronic stress of 6 hours/day for 21 days. Subsequently, the variables were measured in the hippocampus.

RESULTS

The findings revealed that the hippocampal CORT levels in the preventive exercise group had a significant enhancement compared to the control group. In the protective and particularly the therapeutic exercise groups, the hippocampal CORT levels declined. Furthermore, the hippocampal BDNF levels in the preventive and the therapeutic exercise groups indicated significantly decreased and increased, respectively, in comparison with the control group. In the preventive exercise group, however, the hippocampal glucose level turned out to be substantially higher than that in the control group.

CONCLUSION

It appears that the therapeutic exercise group had the best exercise protocols for improving the hippocampal memory mediators in the stress conditions. By contrast, the preventive exercise group could not improve these mediators that had been altered by stress. It is suggested that exercise time, compared to stress, can be considered as a crucial factor in the responsiveness of memory mediators.

Increased serum neurotrophin levels related to alcohol use disorder in a young population sample

BACKGROUND

The diagnosis of alcohol use disorder is based on clinical signs and on the measurement of biological markers. However, these markers are neither sufficiently sensitive, nor specific enough, for determining the effects of alcohol abuse on the central nervous system. Serum neurotrophins are important regulators of neural survival, development, function, and plasticity and have been found to be reduced in alcohol use disorder. The aim of this study was to investigate the alterations in serum neurotrophin levels (brain-derived neurotrophic factor [BDNF], glial-derived neurotrophic factor [GDNF], and nerve growth factor [NGF]) in alcohol use disorder in a young population, and thus possibly representing the early stages of the illness.

METHODS

This is a cross-sectional study, nested in a population-based study of people aged 18 to 35, involving 795 participants. The participants responded to the CAGE questionnaire, and a CAGE score of ≥2 was considered to be a positive screen for the abuse/dependence or moderate to severe alcohol use disorder. Serum BDNF, GDNF, and NGF levels were measured by ELISA.

RESULTS

In the CAGE ≥ 2 group, GDNF (p ≤ 0.001) and NGF (p ≤ 0.001) serum levels were significantly increased, and the BDNF elevation was near a statistical significance (p = 0.068) when compared to the CAGE < 2 group. A significantly positive correlation was observed only in the CAGE ≥ 2 group for BDNF/GDNF (r = 0.37, p < 0.001) and GDNF/NGF (r = 0.84, p < 0.001) levels. The correlation between the NGF and BDNF levels was significantly positive in both groups (r = 0.28, p < 0.001 for the CAGE < 2 group, and r = 0.30, p = 0.008 for the CAGE ≥ 2 group).

CONCLUSIONS

These results suggest that elevated neurotrophins are candidate markers for the early stages of alcohol misuse.

Electrical Intramuscular Stimulation in Osteoarthritis Enhances the Inhibitory Systems in Pain Processing at Cortical and Cortical Spinal System

OBJECTIVE

To determine if in knee osteoarthritis (KOA), one session of active electrical intramuscular stimulation (a-EIMS) compared with sham causes an effect on the motor cortex excitability parameters [motor evoked potential (MEP; the primary outcome), short intracortical inhibition (SICI), intracortical facilitation (ICF) and cortical silent period (CSP)] and pain measurements [pain pressure threshold (PPT); visual analog scale (VAS) and change in numerical pain scale (NPS_0-10 ) during the conditioned pain modulation (CPM)-task]. This study also set out to determine if serum brain-derived neurotrophic factor (BDNF) mediates the effect of treatment on the cortical spinal system as assessed by MEP and PPT.

DESIGN

Randomized clinical trial.

SUBJECTS AND METHODS

Women with KOA, 50-75-years old received a 30-min session of either sham (n = 13) or a-EIMS (n = 13) with 2 Hz. The pain measures and excitability parameters were measured before and immediately after a-EIMS or sham.

RESULTS

The a-EIMS group compared with sham decreased the MEP by 31,67% [confidence interval (CI) 95%, 2.34-60.98]. For the secondary outcomes, the a-EIMS reduced the ICF and increased the CSP but not changed the SICI. The a-EIMS improved the pain reported on VAS, the PPT, and the score of the NPS (0-10) during the CPM-task The BDNF was negatively correlated with the PPT (r = -0.56).

CONCLUSIONS

The serum BDNF revealed an inverse relationship with PPT independent of the treatment group. These results suggest that a-EIMS enhanced the corticospinal inhibitory systems in cortical and infracortical pain processing sites most likely by bottom-up regulation mechanisms.

Aerobic exercise alleviates ischemia-induced memory impairment by enhancing cell proliferation and suppressing neuronal apoptosis in hippocampus

PURPOSE

Neurogenic lower urinary tract dysfunction (NLUTD) is a possible consequence of several neurological disorders. NLUTD may produce debilitating symptoms and serious complications, such as chronic renal failure, and recurrent urinary tract infections. Many animal studies of NLUTD symptoms have focused on animal models of cerebral ischemia. In the present study, we investigated the effects of treadmill exercise on memory function and its relation to cell proliferation and apoptosis in the hippocampus, following transient global ischemia in gerbils.

METHODS

To induce transient global ischemia in gerbil, both common carotid arteries were occluded for 5 minutes. Gerbils in the exercise groups were forced to run on a treadmill exercise for 30 minutes once a day for 2 weeks. Step-down avoidance task and Y maze task were performed. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-staining, immunohistochemistry for 5-bromo-2'-deoxyridine, doublecortin, caspase-3, and Western blot for brain-derived neurotrophic factor (BDNF), Bax, Bcl-2, cytochrome c, caspase-3 were conducted.

RESULTS

Ischemia caused memory impairment with an increase of cell proliferation, BDNF expression, and apoptosis in the hippocampus. Treadmill exercise improved memory function with further increase of cell proliferation and BDNF expression and a decrease of apoptosis.

CONCLUSIONS

The animal model that we have developed and our assessment of the relation between exercise and brain function can be useful tools for future investigations of NLUTD symptoms associated with stroke, particularly ischemic stroke. The present study suggests that treadmill exercise promoted the recovery of brain function after cerebral ischemia.

BDNF in late-life depression: effect of SSRI usage and interaction with childhood abuse

Brain-Derived Neurotrophic Factor (BDNF) serum levels are abnormally low in depressed patients as compared to healthy controls and normalize with SSRI treatment. The aim of this study is to examine serum BDNF levels in late-life depression, stratified for SSRI usage, and to explore the relation between BDNF levels and specific depression characteristics as well as between BDNF levels and early and recent life stressors in late-life depression. We assessed serum BDNF levels in 259 depressed patients not using an SSRI, 99 depressed patients using an SSRI and 119 non-depressed controls (age range 60-93 years). Depressive disorders were diagnosed with the Composite International Diagnostic Interview (CIDI, version 2.1). Serum BDNF levels were significantly higher in depressed patients who used an SSRI compared to depressed patients not using SSRIs and compared to non-depressed controls, when adjusted for age, sex, life style characteristics, cognitive functioning and somatic comorbidity. Recent life-events, assessed with the List of Threatening Events-Questionnaire, were significantly associated with lower BDNF levels in non-depressed subjects only. Although a summary score of early traumatization (before the age of 16 years) was not associated with serum BDNF levels in any of the three groups, we found an interaction between a history of severe physical abuse and SSRI usage in the depressed group. Interestingly, higher serum levels of BDNF in depressed patients using SSRIs were only found in those patients without a history of severe childhood abuse and not in those with a history of severe childhood abuse.

Adenosine A(2A) Receptors as novel upstream regulators of BDNF-mediated attenuation of hippocampal Long-Term Depression (LTD)

Hippocampal Long-Term Potentiation (LTP) is facilitated by BDNF, through the activation of tropomyosin-related kinase B (TrkB) receptors. However, an influence of BDNF upon Long-Term Depression (LTD) was also shown. The present work aimed to further evaluate the effect of BDNF and TrkB receptors upon CA1 hippocampal LTD and to elucidate whether this effect is under the upstream control of other signalling processes, such as the adenosine A(2A)Receptors (A(2A)Rs). LTD, induced by a Low-Frequency Stimulation (LFS, 900 pulses, 1 Hz) in the CA1 area of rat hippocampal slices, was significantly attenuated when these slices were exposed to BDNF (60-100 ng/mL). A lower BDNF concentration (20 ng/ml) was only effective to inhibit LTD if A(2A)Rs were activated by a selective agonist, CGS 21680 (10 nM), or if the extracellular adenosine level was increased by 5-iodotubercidin (100 nM). BDNF (100 ng/ml) effect upon LTD was prevented by K252a (200 nM), which is known to prevent TrkB transphosphorylation, hence suggesting that this action requires TrkB receptor activation. BDNF (100 ng/ml) lacked effect on an adenosine-depleted background (adenosine deaminase, 2 U/ml) or under selective A(2A)R blockade (SCH 58261, 100 nM), indicating that it relies on tonic A(2A)R activation. Forskolin (10 μM), a cell-permeable activator of adenylate cyclase, rescued BDNF (100 ng/ml) effect in slices where A(2A)Rs were blocked with SCH 58261 (100 nM), whereas a PKA inhibitor, H-89 (1 μM), prevented LTD attenuation by BDNF (100 ng/ml). We conclude that the influence of BDNF TrkB receptors upon LTD is under the strict control of A(2A)Rs activation, through a mechanism that requires the cAMP/PKA transducing system.

Trk receptors need neutral sphingomyelinase activity to promote cell viability

Neurotrophins are a group of secreted polypeptides, which comprises Nerve Growth Factor (NGF) and Brain-Derived Neurotrophic Factor (BDNF). Each neurotrophin can bind specifically to a tyrosine kinase Trk receptor (TrkA, TrkB or TrkC), while all of the neurotrophins can bind, with similar affinity, to the p75 neurotrophin receptor (p75(NTR)). Experiments on cell viability promotion by BDNF in granule neurons or by NGF in PC12 cells show that neurotrophin-exerted cell viability is neutral sphingomyelinase (nSMase)-dependent, since GW4869 or siRNA knockdown abrogates the protective effects, as well as neurotrophin-induced Akt phosphorylation. Finally, the assessment of nSMase activity promotion drives to the conclusion that neurotrophins can promote cell viability through Trk receptors in a manner depending on basal nSMase but not through SMase activity enhancement.