BDNF plasma levels decrease during benzodiazepine withdrawal in patients suffering from comorbidity of depressive disorder and benzodiazepine dependence

An Observational Study of Serum Brain Derived Neurotrophic Factor Levels in Patients with Alcohol Dependence during Withdrawal

Brain-Derived Neurotrophic Factor (BDNF) is a neuropeptide that plays an important role in Central Nervous System development, plasticity, learning, and memory. Its role has been explored in alcohol-dependent patients, though the results have been inconclusive. Thus, we aimed to compare serum BDNF levels in alcohol-dependent patients during withdrawal with age and gender matched controls, and assess changes in BDNF levels in the initial abstinence period. BDNF levels of alcohol-dependent patients (n = 25) were compared with controls (n = 25) at baseline. Additionally, BDNF levels were measured in cases on days 5 and 10 of inpatient detoxification. BDNF levels of controls did not differ with cases on day 1, 5, or 10. But BDNF levels increased significantly during alcohol abstinence from baseline to day 10 (Pillai's Trace F = 3.753, p = .039, partial η² = 0.246), which may suggest its protective role. Thus, serum BDNF values may be potentially used as a biomarker to assess the abstinence state. However, longitudinal studies in different body samples is essential to better understand the role of BDNF in alcohol dependence.

The effect of short-term use of benzodiazepines on cognitive function of major depressive disorder patients being treated with antidepressants

BACKGROUND

This study aimed to evaluate the effect of short-term use of benzodiazepines (BZDs) on cognitive function of major depressive disorder (MDD) patients being treated with antidepressants (ADs).

METHODS

This was a part of a multi-center, multi-stage and prospective study of "Objective Diagnostic Indicators and Individualized Drug Intervention of Major Depressive Disorder (OIMDD)". Three hundred and fifty-three patients treated with the selective serotonin reuptake inhibitors (SSRIs) alone (Group 1) and 49 patients treated with SSRIs combined with short-term use of BZDs (Group 2) during the acute treatment period were included in the analysis. Cognitive function and depressive and anxiety symptoms were assessed at baseline, weekend 8 and 48. A cognitive test battery included 5 domains: information processing speed assessed by the Animal Verbal Fluency Scale (AVFS), Digit Symbol Coding Test (DSCT) and Color Trial Test (CTT), verbal learning assessed by the Hopkins Verbal Learning Test-Revised (HVLT-R), visual learning assessed by the Brief Visual Memory Test-Revised (BVMT-R), executive function assessed by the Stroop Color Word Test (SCWT), and attention or vigilance assessed by the Continuous Performance Test (CPT).

RESULTS

Significant differences were found in education level (χ² = 5.442, p = 0.020), the severity of depressive (t = -1.982, p = 0.048) and anxiety symptoms (t = -2.629, p = 0.009) between Group 1 and 2 at baseline. There were no significant differences between G1 and G2 in cognitive functions at baseline. After Multiple correction, DSCT was better in patients treated with BZDs combined with ADs than in patients with ADs alone at weekend 8 without controlling education level, depressive and anxiety symptoms at baseline (F = -2.747, p = 0.042). After controlling these factors at baseline, the DSCT was still slightly high in patients treated with ADs combined with BZDs than in patients with ADs alone at weekend 8 (OR = 1.052, 95%CI:1.000-1.105). The repeated measurement analysis of variance showed that the DSCT could be improved by the treatment of BZDs combined with ADs at 1-year follow-up compared to baseline (F = 7.569, p = 0.006).

CONCLUSIONS

The findings suggest that short-term use of BZDs does not impair cognitive function of MDD patients; conversely, it could improve the information processing speed after acute treatment and at 1 year follow up.

Brain-derived neurotrophic factor in substance use disorders: A systematic review and meta-analysis

BACKGROUND

Brain-derived neurotrophic factor (BDNF) is associated with several neurodegenerative and psychiatric disorders. It is not clear, however, whether BDNF levels are modified in substance use disorders (SUDs).

METHODS

We conducted a systematic search of electronic databases to identify studies comparing peripheral plasma or serum BDNF levels in adults with SUDs vs. non-user controls. Forty studies were included in the meta-analysis involving a total of 2238 participants with SUDs and 2574 controls.

RESULTS

After trim and fill adjustment, current drug users presented lower serum BDNF levels (SMD = -0.99, 95%CI -1.40 to -0.58, I² = 95.9) than non-user controls. However, this difference disappears during withdrawal. Studies using serum or plasma BDNF samples have shown different results. Subgroup analysis revealed lower levels of serum BDNF in alcohol users (SMD = -0.70, 95%CI -1.15 to -0.25, I² = 89.81) and crack/cocaine users (SMD = -1.78, 95%CI -2.92 to -0.65, I² = 97.59) than controls. Meta-regression analysis revealed that gender, age, and age of first use moderate the effects of drug use in peripheral BDNF levels.

CONCLUSIONS

Peripheral BDNF levels are decreased in the serum, but not the plasma, of active drug users. Altogether, these findings suggest that BDNF levels may be related to acute use and addiction severity and also point to BDNF's potential utility as a biomarker in this population.

Role of glial cell line-derived neurotrophic factor in the pathogenesis and treatment of mood disorders

Glial cell line-derived neurotrophic factor (GDNF) is widely recognized as a survival factor for dopaminergic neurons, but GDNF has also been shown to promote development, differentiation, and protection of other central nervous system neurons and was thought to play an important role in various neuropsychiatric disorders. Severe mood disorders, such as primarily major depressive disorder and bipolar affective disorder, attract particular attention. These psychopathologies are characterized by structural alterations accompanied by the dysregulation of neuroprotective and neurotrophic signaling mechanisms required for the maturation, growth, and survival of neurons and glia. The main objective of this review is to summarize the recent findings and evaluate the potential role of GDNF in the pathogenesis and treatment of mood disorders. Specifically, it describes (1) the implication of GDNF in the mechanism of depression and in the effect of antidepressant drugs and mood stabilizers and (2) the interrelation between GDNF and brain neurotransmitters, playing a key role in the pathogenesis of depression. This review provides converging lines of evidence that (1) brain GDNF contributes to the mechanism underlying depressive disorders and the effect of antidepressants and mood stabilizers and (2) there is a cross-talk between GDNF and neurotransmitters representing a feedback system: GDNF-neurotransmitters and neurotransmitters-GDNF.

Effect of XingPiJieYu decoction on spatial learning and memory and cAMP-PKA-CREB-BDNF pathway in rat model of depression through chronic unpredictable stress

BACKGROUND

Depression is a mental disorder characterized by a pervasive low mood and loss of pleasure or interest in usual activities, and often results in cognitive dysfunction. The disturbance of cognitive processes associated with depression, especially the impairment of learning and memory, exacerbates illness and increases recurrence of depression. XingPiJieYu (XPJY) is one of the most widely clinical formulas of traditional Chinese medicine (TCM) and can improve the symptoms of depression, including learning and memory. However, its regulatory effects haven't been comprehensively studied so far. Recently, some animal tests have indicated that the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA)-cAMP response element-binding protein (CREB)-brain derived neurotrophic factor (BDNF) signaling pathway in hippocampus is closely related to depression and the pathogenesis of cognitive function impairments. The present study was performed to investigate the effect and mechanism of XPJY on depression and learning and memory in animal model.

MATERIALS

The rat model of depression was established by chronic unpredictable stress (CUS) for 21 days. The rats were randomly divided into six groups: control group, CUS group, CUS + XPJY (1.4 g/kg, 0.7 g/kg and 0.35 g/kg) groups, and CUS + sertraline (10 mg/kg) group. The sucrose preference, open field exploration and Morris water maze (MWM) were tested. The expression of cAMP, CREB, PKA and BDNF protein in hippocampus was examined with Elisa and Western Blot. The mRNA level of CREB and BDNF in hippocampus was measured with PCR.

RESULTS

The results demonstrated that rats subjected to CUS exhibited decreases in sucrose preference, total ambulation, percentage of central ambulation, rearing in the open field test and spatial performance in the MWM. CUS reduced the expression of cAMP, PKA, CREB and BDNF in hippocampus of model rats. These effects could be reversed by XPJY.

CONCLUSION

The results indicated that XPJY can improve depression and related learning and memory and the effect of XPJY is partly exerted through the cAMP-PKA-CREB-BDNF signaling pathway.

Hypothalamic-pituitary-adrenal axis hyperactivity is associated with decreased brain-derived neurotrophic factor in female suicide attempters

INTRODUCTION

Both decreased levels of brain-derived neurotrophic factor (BDNF) and hypothalamic-pituitary-adrenal (HPA) axis dysregulation may be involved in the pathophysiology of suicidal behaviour, as well as cognitive symptoms of depression. Pre-clinical and clinical studies have shown interactions between HPA-axis activity and BDNF, but this has not been studied in a clinical cohort of suicidal subjects. The purpose of this study was, therefore, to investigate associations between HPA-axis activity and BDNF in suicide attempters. Furthermore, this study examined the relationship between the HPA-axis, BDNF, and cognitive symptoms in suicidal patients. Since previous data indicate gender-related differences in BDNF and the HPA axis, males and females were examined separately.

METHOD

Seventy-five recent suicide attempters (n = 41 females; n = 34 males) were enrolled in the study. The Dexamethasone Suppression Test (DST) was performed and BDNF in plasma were analysed. Patients were evaluated with the Comprehensive Psychopathological Rating Scale (CPRS) from which items 'Concentration difficulties' and 'Failing memory' were extracted.

RESULTS

Only among females, DST non-suppressors had significantly lower BDNF compared to DST suppressors (p = 0.022), and there was a significant correlation between post-DST serum cortisol at 8 a.m. and BDNF (rs = -0.437, p = 0.003). Concentration difficulties correlated significantly with post-DST cortisol in all patients (rs = 0.256, p = 0.035), in females (rs = 0.396, p = 0.015), and with BDNF in females (rs = -0.372, p = 0.020).

CONCLUSION

The findings suggest an inverse relationship between the HPA-axis and BDNF in female suicide attempters. Moreover, concentration difficulties may be associated with low BDNF and DST non-suppression in female suicide attempters.

Decreased glial cell line-derived neurotrophic factor levels in patients with depression: a meta-analytic study

Glial cell-line derived neurotrophic factor (GDNF) has been shown to promote development, differentiation, and protection of CNS neurons and was thought to play an important role in various neuropsychiatric disorders. Several studies have examined the GDNF levels in patients with depression but shown inconsistent results. In this study, we compared blood GDNF levels between depressive patients and control subjects through meta-analytic method. The effect sizes (ESs) from all eligible studies were synthesized by using a random effect model. In this meta-analysis, we included 526 patients and 502 control subjects from 12 original articles. Compared to control subjects, blood GDNF levels are significantly decreased in patients with depression (ES = -0.62, p = 0.0011). However, significant heterogeneity was found among included studies. Through subgroup analysis, we found that GDNF was still decreased in studies with major depressive disorder (ES = -0.73, p = 0.0001); in studies with non-old-age depression (ES = -1.25, p = 0.0001), but not with old-age depression; and in studies using serum samples (ES = -0.86, p < 0.0001), but not in studies using plasma sample. Meta-regression did not show moderating effects of mean age of subjects, gender distribution, and age of onset of depression. Our findings support blood GDNF levels as a biomarker of depression as a whole, but the results were modulated by psychiatric diagnosis, age of included subjects, and sampling sources. With these results, future studies are required to examine whether effective antidepressant treatment is associated with an increase in serum GDNF levels.

ATP induced brain-derived neurotrophic factor expression and release from osteoarthritis synovial fibroblasts is mediated by purinergic receptor P2X4

Brain-derived neurotrophic factor (BDNF), a neuromodulator involved in nociceptive hypersensitivity in the central nervous system, is also expressed in synoviocytes of osteoarthritis (OA) and rheumatoid arthritis (RA) patients. We investigated the role of P2 purinoreceptors in the induction of BDNF expression in synovial fibroblasts (SF) of OA and RA patients. Cultured SF from patients with symptomatic knee OA and RA were stimulated with purinoreceptor agonists ATP, ADP, or UTP. The expression of BDNF mRNA was measured by quantitative TaqMan PCR. BDNF release into cell culture supernatants was monitored by ELISA. P2X4 expression in synovial tissue was detected by immunohistochemistry. Endogenous P2X4 expression was decreased by siRNA transfection before ATP stimulation. Kinase pathways were blocked before ATP stimulation. BDNF mRNA expression levels in OASF were increased 2 h and 5 h after ATP stimulation. Mean BDNF levels in cell culture supernatants of unstimulated OASF and RASF were 19 (±9) and 67 (±49) pg/ml, respectively. BDNF levels in SF supernatants were only elevated 5 h after ATP stimulation. BDNF mRNA expression in OASF was induced both by P2X receptor agonists ATP and ADP, but not by UTP, an agonist of P2Y purinergic receptors. The ATP-induced BDNF mRNA expression in OASF was decreased by siRNA-mediated reduction of endogenous P2X4 levels compared to scrambled controls. Inhibition of p38, but not p44/42 signalling reduced the ATP-mediated BDNF mRNA induction. Here we show a functional role of the purinergic receptor P2X4 and p38 kinase in the ATP-induced expression and release of the neurotrophin BDNF in SF.

Fluoxetine ameliorates behavioral and neuropathological deficits in a transgenic model mouse of α-synucleinopathy

The term α-synucleinopathies refers to a group of age-related neurological disorders including Parkinson's disease (PD), Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) that display an abnormal accumulation of alpha-synuclein (α-syn). In contrast to the neuronal α-syn accumulation observed in PD and DLB, MSA is characterized by a widespread oligodendrocytic α-syn accumulation. Transgenic mice expressing human α-syn under the oligodendrocyte-specific myelin basic protein promoter (MBP1-hαsyn tg mice) model many of the behavioral and neuropathological alterations observed in MSA. Fluoxetine, a selective serotonin reuptake inhibitor, has been shown to be protective in toxin-induced models of PD, however its effects in an in vivo transgenic model of α-synucleinopathy remain unclear. In this context, this study examined the effect of fluoxetine in the MBP1-hαsyn tg mice, a model of MSA. Fluoxetine administration ameliorated motor deficits in the MBP1-hαsyn tg mice, with a concomitant decrease in neurodegenerative pathology in the basal ganglia, neocortex and hippocampus. Fluoxetine administration also increased levels of the neurotrophic factors, GDNF (glial-derived neurotrophic factor) and BDNF (brain-derived neurotrophic factor) in the MBP1-hαsyn tg mice compared to vehicle-treated tg mice. This fluoxetine-induced increase in GDNF and BDNF protein levels was accompanied by activation of the ERK signaling pathway. The effects of fluoxetine administration on myelin and serotonin markers were also examined. Collectively these results indicate that fluoxetine may represent a novel therapeutic intervention for MSA and other neurodegenerative disorders.

Serum levels of BDNF are associated with craving in opiate-dependent patients

Preclinical study results suggest that brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) are involved in the modulation of addictive behaviour. We investigated alterations in serum levels of BDNF and GDNF in opiate-dependent patients (28 males) who received diacetylmorphine treatment within a structured opiate maintenance programme. BDNF (T = 2.735, p = 0.009) serum levels were significantly increased in the opiate-dependent patients as compared with healthy controls (21 males), whereas GDNF serum levels (T = 1.425, p = 0.162) did not differ significantly from GDNF serum levels of the healthy controls. BDNF serum levels were significantly associated with craving for heroin (measured by the Heroin Craving Questionnaire (r = 0.420, p = 0.029) and by the General Craving Scale (r = 0.457, p = 0.016), whereas GDNF serum levels were not associated with psychometric dimensions of heroin craving. In conclusion, our results show a positive association between BDNF serum levels and opiate craving in opiate-dependent patients.

BDNF and GDNF serum levels in alcohol-dependent patients during withdrawal

Preclinical study results suggest that brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) modulate addictive behaviour. Therefore we investigated alterations in BDNF (81 male patients) and GDNF serum levels (52 male patients) in alcohol-dependent patients during alcohol withdrawal (day 1, 7 and 14) in comparison to healthy controls (41 male controls). BDNF serum levels were not significantly altered in alcohol-dependent patients compared to healthy controls (p=0.685). GDNF serum levels were significantly reduced in the alcohol-dependent patients (p<0.001). BDNF (p=0.265) and GDNF (p=0.255) serum levels did not change significantly during alcohol withdrawal. BDNF serum levels were significantly negatively associated with alcohol withdrawal severity on day 1 (CIWA-Ar score, p=0.004). GDNF serum levels were significantly negatively associated with individual estimation of alcohol tolerance (SESA-XT score, p=0.028). There was no further association with psychometric dimensions of alcohol withdrawal. In conclusion we found that GDNF serum levels are significantly reduced in alcohol-dependent patients. GDNF serum levels were negatively associated with alcohol tolerance. Moreover BDNF serum levels were found to be associated with withdrawal severity.