Serum Brain-derived Neurotrophic Factor Concentrations Research Articles

Association Between the Enriched Environment Level and Serum Brain-Derived Neurotrophic Factor (BDNF) in Patients with Major Depressive Disorder

Major Depressive Disorder (MDD) is a neuropsychiatric condition whose neurobiological characteristics include alterations in brain plasticity, modulated by Brain-Derived Neurotrophic Factor (BDNF). In animal models, environmental enrichment promotes neuroplasticity and reduces depressive-like behaviors. In humans, we proposed to assess the level of Enriched Environment (EE) using a questionnaire that includes different domains of the EE (cognitive, social, and physical), which we named the EE Indicator (EEI). Objective: To determine the relationship between the level of EE and serum BDNF in participants with MDD and healthy controls. Materials: Participants with MDD without antidepressant treatment and healthy controls were recruited, and their EE level and serum BDNF concentration were determined looking for correlations between their clinical characteristics and the cognitive, social, and physical activities according to the EEI. Results: A total of 25 participants were recruited, of which 6 participants with MDD and the same number of controls were selected in a paired manner. Although no differences were found in the concentration of BDNF between the groups, positive correlations were observed between cognitive EE and BDNF (r = 0.62, p = 0.035), as well as negative social EE and the Hamilton Depression Rating Scale (HDRS) (r = −0.86, p = 0.001). The sum between cognitive and social EE showed a positive correlation with the serum concentration of BDNF (r = 0.34, p = 0.0451). Conclusions: The level of EE is potentially modulating the presence and severity of MDD at a clinical level, but it can also influence at a neuroplastic level through promoting or limiting the concentration of BDNF.

Effect of a 12-Week High Intensity Interval Training on Serum Brain Derived Neurotrophic Factor of Obese Undergraduates

The study investigated the effect of a 12-week High Intensity Interval Training (HIIT) on Serum Brain Derived Neurotrophic Factor (BDNF) among obese undergraduates of the University of Benin. The pretest-posttest randomized experimental design was employed for the study. The study involved a population of one hundred and twenty obese undergraduates, with a sample of twenty-four selected using simple random sampling. The participants’ anthropometric profiles were analyzed descriptively using mean and standard deviation, and the hypothesis was tested using analysis of covariance (ANCOVA) with statistical significance set at a p-value of <0.05. The Bonferroni post-hoc test was conducted to pinpoint the source of the differences between the groups. The results showed a significantly higher increase in Serum BDNF levels (2.07 ± 1.9 vs. 2.38 ± 2.1) in the experimental group. This suggests that the HIIT protocol had a notable impact on the serum BDNF concentration of the obese undergraduates. Therefore, HIIT may serve as an effective intervention for elevating BDNF levels and potentially enhancing brain health. The study recommends that policymakers in Nigeria and other sub-Saharan African nations should prioritize addressing obesity due to its potential cognitive complications.

Smoking-Dependent Association of Serum Brain-Derived Neurotrophic Factor with Pulmonary Function Parameters in Chronic Obstructive Pulmonary Disease.

Background and Objectives: One of the members of the neurotrophin (NT) family is the brain-derived neurotrophic factor (BDNF). In addition to its role in the nerve system, it has been found to play a role in lung health and diseases. Materials and Methods: The serum concentrations of BDNF were assessed in 57 patients with COPD and in 19 control individuals and the possible associations of BDNF with the spirometric indexes and disease stages were explored. Results: We did not find a significant difference between the serum concentrations of BDNF of patients and controls (p = 0.521). A significant negative correlation of the serum BDNF levels with the age of the patients (Rho = -0.279, p = 0.036) was observed. In addition, a borderline negative correlation with the age of disease onset (Rho= -0.244, p = 0.063) was also found. When analyzing these correlations in different genders, we found stronger statistical significance in male patients (Rho = -0.398, p = 0.009; and Rho = -0.419, p = 0.006), while no such significance was found in females (p = 0.574 and p = 0.342). The analyses of the possible relations of serum BDNF concentration with the spirometric parameters in the whole group of patients did not reveal any significance (p = 0.231 for FEV1%pr. and p = 0.271 for FEV1/FVC%). However, when the patients were dichotomized on the basis of smoking habits, we obtained a strong positive correlation between BDNF and FEV1%pr. (Rho = 0.501, p = 0.048) in non-smokers, but strong negative correlations with FEV1%pr. (Rho = -0.468, p = 0.003) and with FEV1/FVC% (Rho = -0.331, p = 0.040) in ex/current smokers. Non-smokers with moderate disease (GOLD II) had higher BDNF serum concentrations than patients with GOLD stage III/IV (p = 0.031). In ex/current smokers, there was an opposite association (p = 0.045). Conclusions: The results of our study suggest that the expression and secretion of BDNF are changed in COPD, but its effects and functions may differ according to the smoking history of the patients.

Cognitive functions and the brain-derived neurotrophic factor in patients with mild autonomous cortisol secretion.

The impact of abnormal cortisol secretion on cognitive functions in patients with mild autonomous cortisol secretion (MACS) remains uncertain. To assess cognitive functions, determine serum brain-derived neurotrophic factor (BDNF) concentration in patients with MACS, and investigate the association between cognitive subdomains and BDNF. We prospectively recruited 84 participants-28 patients with MACS, 28 patients with nonfunctional adrenal adenoma (NFAA), and 28 control subjects matched for age, gender, body mass index (BMI), visceral adiposity, and educational level. The serum BDNF concentration of participants was measured. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition-focused interviews and Montreal Cognitive Assessments (MoCA) were carried out by an experienced psychiatrist. Patients with MACS had a higher serum BDNF concentration than the NFAA (P = .001), while that of patients with NFAA was lower than the controls (P = .044). Linear regression analysis revealed BMI and morning cortisol after overnight 1 mg dexamethasone (DST) were mostly associated with BDNF (P < .05). No significant difference was found in MoCA scores between MACS and NFAA groups (P = .967), whereas those were lower than the control group (P = .004). When the cognitive subdomains were examined separately, MACS group performed higher memory score than NFAA (P = .045), but lower language scores than both the NFAA (P = .024) and control groups (P < .001). In the whole group, BDNF concentration was positively correlated with memory score (r = 0.337, P = .002), whereas DST was negatively correlated with language score (r = -0.355, P = .008). Low-grade hypercortisolism is associated with elevated BDNF concentrations, which may be a protective factor for memory function in patients with MACS relative to those with NFAA.

Oral administration of liposome-encapsulated thymol could alleviate the inflammatory parameters in serum and hippocampus in a rat model of Alzheimer's disease

BackgroundNeuroinflammation is closely related to Alzheimer's Disease (AD) pathology, hence supplements with anti-inflammatory property could help attenuate the progression of AD. This study was conducted to evaluate the potential anti-inflammatory effects of liposome encapsulated thymol (LET), administered orally, in prevention of Alzheimer in a rat model by anti-inflammatory mechanisms. MethodsThe rats were grouped into six groups (n = 10 animals per group), including Control healthy (Con), Alzheimer's disease (AD) model, AD model treated with free thymol in 40 and 80 mg/kg body weight (TH40 and TH80), AD model treated with LET in 40 and 80 mg/kg of body weight (LET40 and LET80). The behavioral response of step through latency (Passive Avoidance Test), concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) and brain-derived neurotrophic factor (BDNF) were assessed in serum and hippocampus. ResultsThe results showed that significant increase in concentrations of IL-1β (P = 0.001), IL-6 (P = 0.001), TNF-α (P = 0.001) and COX-2 (P = 0.001) in AD group compared with healthy control rats. AD induction significantly reduced step through latency and revealed deficits in passive avoidance performance. The results also showed the treatment with free thymol especially in higher concentrations and also LTE could decrease serum concentrations of IL-1β (P < 0.05), IL-6 (P < 0.05), TNF-α (P < 0.05), and COX-2 (P < 0.05) and increase BDNF (P < 0.05) compared with control Alzheimer rats in hippocampus and serum. There were also significant correlations between serum and hippocampus concentrations of IL-1β (r2 = 0.369, P = 0.001), IL-6 (r2 = 0.386, P = 0.001), TNF-α (r2 = 0.412, P = 0.001), and COX-2 (r2 = 0.357, P = 0.001). It means a closed and positive relation between serum and hippocampus concentrations of IL-1β, IL-6, TNF-α, and COX-2. ConclusionsLET demonstrates its ability to attenuate neuroinflammatory reaction in AD model through suppression of IL-1β, IL-6, and TNF-α and COX-2 indicators. Hence, it can ameliorate AD pathogenesis by declining inflammatory reaction.

Long-term effects of an egg-protein hydrolysate on cognitive performance and brain vascular function: a double-blind randomized controlled trial in adults with elevated subjective cognitive failures

PurposeShort-term intake of the egg-protein hydrolysate Newtricious (NWT)-03 improved executive function, but underlying mechanisms and long-term effects, including other cognitive domains, are unknown.MethodsA 36-week randomized controlled trial involving 44 overweight/obese individuals experiencing elevated Subjective Cognitive Failures (SCF; aged 60–75 years) assessed the impact of daily consumption of 5.7 g of NWT-03 or placebo powders on cognitive performance (psychomotor speed, executive function, memory) and Cerebral Blood Flow (CBF), a marker of brain vascular function. Cognitive performance was evaluated using a neurophysiological test battery (CANTAB) and CBF was measured using magnetic resonance imaging perfusion method Arterial Spin Labeling (ASL). Serum samples were collected to determine brain-derived neurotrophic factor (BDNF) concentrations.ResultsAnthropometrics, and energy and nutrient intakes remained stable throughout the trial. NWT-03 was well tolerated, and compliance was excellent (median: 99%; range: 87–103%). No overall intervention effects were observed on cognitive performance or CBF, but post-hoc analyses revealed significant improvements on executive function in women, but not men. Specifically, a reduction of 74 ms in reaction latency on the multitasking task (95% CI: −134 to −15; p = 0.02), a reduction of 9 between errors (95%CI: −14 to −3; p < 0.001), and a reduction of 9 total errors (95%CI: −15 to −3; p < 0.001) on the spatial working memory task were found in women. No intervention effects were observed on serum BDNF concentrations (p = 0.31).ConclusionLong-term consumption of NWT-03 improved multitasking abilities and working memory in women with elevated SCF. Brain vascular function remained unaffected. Sex differences in executive function require additional clarification.

Effects of antidepressant and antipsychotic medication on peripheral brain-derived neurotrophic factor concentration: Systematic review and meta-analysis

Brain-derived neurotrophic factor (BDNF) is an important regulatory protein in the pathophysiology of psychiatric disorders. Several studies have reported the relationship between peripheral BDNF concentrations and the use of psychoactive drugs. However, the results remain controversial. This study aimed to evaluate the effects of psychoactive drugs on BDNF concentrations and to explore the association between changes in BDNF concentrations and improvements in clinical scores. A systematic review and meta-analysis were conducted. Six electronic databases, including PubMed, Scopus, Medline, Web of Science, Google Scholar and Science Direct, were searched. Changes in BDNF concentrations were compared before and after psychoactive treatment, using the standardized mean difference (SMD) and 95 % confidence interval (95 % CI). Twenty-three studies were included. A significant increase in serum BDNF concentrations was observed after treatment with antipsychotics (SMD=0.43; 95 %CI: 0.26, 0.60) and antidepressants (SMD=0.49; 95 %CI: 0.23, 0.74). However, the plasma BDNF concentration was not affected by antidepressant and antipsychotic medication. Although an improvement in clinical scores was observed after treatment, no significant association was observed between changes in BDNF concentrations and the changes in the Positive and Negative Syndrome Scale (PANSS) and the Hamilton Depression Rating Scale (HAM-D) scores. In conclusion, antidepressants and antipsychotics increase serum BDNF concentrations.

Relationship between brain-derived neurotrophic factor and mild to moderate cognitive impairment in the older Mexican population

BackgroundMild–moderate cognitive impairment is a frequent pathology in the adult population. It is important to explore early expression biomarkers that contribute to early detection and benefit the prognostic outlook. Brain-derived neurotrophic factor (BDNF) is an essential regulator of synaptic plasticity, neuronal survival, and differentiation, and even a critical molecular target for drug development in neurological disorders. It is crucial to carry out studies in the early stages that better clarify the landscape of BDNF. ObjectiveTo compare the serum levels of BDNF in healthy adult patients and those with mild to moderate cognitive impairment. Materials and methodsA casecontrol study in patients over 55- years with cognitive impairment, obtained by the MMSE® and MoCA® screening scales. A total of 191 patients, 102 patients with cognitive impairment (cases) and 89 healthy ones (controls) participated in the study. Blood samples were collected to obtain serum, with the determination of BDNF concentrations. For differences in BDNF concentrations, a one-way analysis of variance was used. The significance level of p<.05. ResultsThe mean serum concentration of BDNF in the case group was 277.68±75.09 vs. the control group, where the concentration was 354.97±66.06 pg/ml (p=.001). ConclusionsThere is an association between decreased BDNF levels and mild and moderate cognitive impairment in our study population.

Short-term Aronia melanocarpa extract supplementation improves cognitive performance: a randomized, double-blind, placebo-controlled cross-over study in healthy young adults

PurposeEvidence on the potential beneficial effects of anthocyanin-rich foods and supplements on cognitive performance is mainly based on acute or long-term studies in older adults. However, short-term studies focusing on a younger population are lacking. Therefore, short-term effects of Aronia melanocarpa extract (AME) supplementation on cognitive performance were investigated in healthy young adults. Potential underlying mechanisms were also addressed.MethodsA randomized, double-blind, placebo-controlled cross-over study was performed involving 35 apparently healthy young adults. Participants consumed AME (180 mg anthocyanins/day) or a placebo for 1 week, separated by at least 2 weeks of wash-out. Cognitive performance was assessed using the Cambridge Neuropsychological Test Automated Battery (CANTAB). Furthermore, arterial stiffness (carotid-to-femoral pulse wave velocity), retinal microvascular calibers (fundus photography), and serum brain-derived neurotrophic factor (BDNF) concentrations were measured at baseline and after 1 week.ResultsParticipants had a mean age of 25 ± 4 years and an average BMI of 23.4 ± 2.7 kg/m2. Compliance was excellent and the study product was well-tolerated. As compared to placebo, movement time was significantly reduced by 4.8% within the five-choice reaction time test after 1 week of AME supplementation (intervention effect: – 12 ms; p < 0.05). Memory and executive function did however not change. Serum BDNF concentrations were significantly higher after AME supplementation as compared to placebo (+ 5.7%; intervention effect: 1.8 ng/mL; p < 0.05). However, arterial stiffness and retinal microvascular calibers were not affected.ConclusionShort-term AME supplementation beneficially affected cognitive performance as attention and psychomotor speed improved. Serum BDNF concentrations were increased, but vascular function markers were not affected.Clinical trial registrationThe study was registered on Clinical Trials under NCT03793777 on January 4th, 2019.

Assessment of brain-derived neurotrophic factor levels in serum of children with autism spectrum disorders

BackgroundThe autism spectrum disorder (ASD) has no identified biomarker for early detection or for its severity. As for the brain-derived neurotrophic factor (BDNF), it is a crucial neurotropic factor that regulates the plasticity and maturing of neuronal synapses. Accordingly, it might influence how children with autism develop.MethodTo evaluate the BDNF serum levels in autistic children and their relationship with the illness severity as well as with the common drugs received by autistic patients, 60 patients with autism along with another 60 normally developing children were involved in the study. Using the Childhood Autism Rating Scale (CARS), the severity of autism was then evaluated. The ELISA method was used to measure the BDNF level.ResultsIt was seen that the BDNF concentrations were higher in autism patients (P < 0.001). There was also a highly strong positive association between the CARS score and the BDNF (P < 0.001). Using the cut-off value of > 2.8 of BDNF helped to distinguish between well-developing and autistic children, with the aspects of “sensitivity” and “specificity” being 88.3% and 80%, respectively. Moreover, children with autism who received omega-3 had statistically lower levels of BDNF than those who did not take any (P = 0.040).ConclusionThe serum BDNF concentration is higher in autism; this proposes that the BDNF may contribute to the onset or progress of autism. Therefore, it may be used as a noninvasive biomarker for the illness severity because of its greater occurrence in autistic children who have severe social impairment.

Peripheral Levels of the Brain-Derived Neurotrophic Factor in Coronary Artery Disease: A Systematic Review and Meta-Analysis.

Among its functions, brain-derived neurotrophic factor (BDNF) regulates endothelial and macrophage activation, possibly playing a role in atherosclerotic plaque pathophysiology. Given contradicting reports, this study sought to investigate whether blood levels of BDNF differed between patients with coronary heart disease (CHD) and controls. We explored PubMed, Embase, Web of Science, and Cochrane Library for studies comparing BDNF blood levels in patients with CHD and controls. Random-effect meta-analysis was conducted to calculate the standardized mean differences (SMD) and 95% confidence intervals (CI). The Newcastle-Ottawa scale was used to evaluate the quality of included articles, and statistical analyses were conducted using R version 4.0.4. The final analysis comprised 12 investigations covering 1422 CHD cases and 929 controls with mean ages of 59.66±13.56 and 53.78±13.61 years, respectively. The initial analyses revealed a tendency toward low levels of BDNF in the CHD group compared with the control group (SMD= -0.41; 95% CI, -1.12 to 0.30; P=0.26). After the removal of outliers, the difference achieved statistical difference (SMD= -0.56; 95% CI, -0.93 to -0.19; P<0.01). Subgroup analysis demonstrated no significant difference between serum and plasma BDNF levels (P=0.54); however, subgroup analyses of studies investigating plasma BDNF showed that patients with CHD had significantly lower BDNF levels. Serum and plasma BDNF concentrations were considerably lower in patients with CHD than in healthy controls. Further studies of higher quality are required on the potential role of BDNF as a biomarker of CHD pathophysiology and severity.

Serum brain-derived neurotrophic factor concentration is different between autism spectrum disorders and intellectual disability children and adolescents

PurposeRecent studies showed that mature brain-derived neurotrophic factor (mBDNF) and its precursor proBDNF are associated with autism spectrum disorders (ASD). Whether their levels are different between ASD and intellectual disability (ID) subjects is not clear. The aim of this study is to compare the serum mBDNF and proBDNF concentration, and mBNDF/proBDNF ratio in ASD and ID volunteers. MethodsChildren and adolescents with ASD or ID between the ages of 4 and 22 were recruited in Tianjin, China. Serum mBDNF and proBDNF level were tested and Wechsler Preschool and Primary Scale of Intelligence (WPPSI), Wechsler Intelligence Scale for Children (WISC), and Childhood Autism Rating Scale (CARS) evaluations were conducted. ResultsSerum mBDNF concentration and the ratio of mBDNF to proBDNF was higher in ASD subjects than that in ID subjects (P = 0.035 and P < 0.001, respectively), while serum proBDNF of ASD participants was lower compared to that of ID participants (P < 0.001). CARS score was positively correlated with serum mBDNF level (r = 0.33, P = 0.004) and m/p ratio (r = 0.39, P < 0.001), and negatively correlated with serum proBDNF level (r = −0.39, <0.001) after adjusting for age and IQ. The AUC of mBDNF, proBDNF, and m/p ratio were 0.741, 0.790, and 0.854, respectively, after adjusted for age and IQ. ConclusionSerum mBDNF, proBDNF and m/p ratio were different between ASD and ID group. The three biomarkers displayed good diagnostic values for classification of ASD and ID subjects.

Daily cannabidiol and L-theanine beverage consumption does not alter anxiety, fatigue, cognitive function, or natural killer cell function: A randomized, controlled trial in healthy, young adults

Cannabidiol (CBD), a non-psychotropic Cannabis sativa derivative, and L-theanine, a green tea derivative, are gaining attention as potential promotors of psychological and cognitive health. The purpose of this double-blind, randomized, placebo-controlled study was to determine whether eight-week, daily consumption of beverages containing CBD, along with L-theanine, would improve psychological health, cognitive function, serum brain-derived neurotrophic factor (BDNF) as well as innate immune cell quantity and function in young, healthy adults. A total of 102 healthy participants were randomly assigned to, and successfully completed, 8 weeks of one of four treatment arms: 1) 60 mg CBD plus L-theanine (CB60; n = 25); 2) 30 mg CBD plus L-theanine (CB30; n = 28); 3) vehicle containing only L-theanine (LTV; n = 24); and 4) a calorie-matched placebo (PLAC; n = 25). After 8 weeks, plasma cannabinoid metabolite concentrations were significantly increased (p < 0.001) in CB60 and CB30 groups. There were no significant changes in anxiety, fatigue, and cognition, or serum BDNF concentrations as a result of the intervention and no treatment-related changes in natural killer (NK) and NKT cell populations or function. ClinicalTrials.gov (NCT05189275).

Influence of rehabilitation with the use of sulphide and hydrogen sulphide baths on the concentration of the brain-derived neurotrophic factor (BDNF) and selected parameters of cognitive, executive and affect functions in multiple sclerosis patients

Aim: To compare the blood serum BDNF concentration in MS patients before and after a standard three-week rehabilitation offered by the NHF. The study compared the expected growth of the BDNF concentration in a group of patients rehabilitated with the help of standard kinesiotherapy and a group of patients rehabilitated with kinesiotherapy plus sulphide and hydro sulphide baths as well as the results of the assessment of the cognitive and executive functions of MS patients in the two groups. Materials and methods: Participants in the study were divided into 3 groups of 20 people each. Group 1. MS patients rehabilitated for 3 weeks in the Day Ward of the Rehabilitation Clinic – standard kinesiotherapy. Group 2. MS patients rehabilitated for 3 weeks in the Day Ward of the Rehabilitation Clinic – kinesiotherapy with sulphide baths. Group 3. Healthy volunteers – occasional BDNF determination. In the group of MS patients the BDNF concentration was determined prior to and after the rehabilitation. Group 3 was monitored for BDNF levels initially lower than in MS patients. Results: Rehabilitation of MS patients with kinesiotherapy and sulphide baths causes a statistically higher growth of BDNF concentration than rehabilitation alone in this group of patients (p&lt;0.001). Results of neuropsychological tests of MS patients rehabilitated with kinesiotherapy and balneotherapy elements are statistically better than of patients rehabilitated with kinesiotherapy (p&lt;0.033). Conclusions: Research findings show that sulphide and hydro sulphuric baths seem to be a valuable supplement to MS patients’ rehabilitation.

Serum biomarkers in normal pressure hydrocephalus.

Aim To investigate the serum value of brain derived neurotrophic factor (BDNF), proteins S-100, NSE, IL-6 in normal pressure patients (NPH) compared to control (healthy) group and also a possible correlation with radiological findings in NPH patients. Methods Study patients were included during the period of 2020- 2022. All NPH patients met the diagnostic criteria for probability of NPH. Control patients group included patients without known brain disorder, without clinical symptoms of NPH. Blood samples were taken before planned surgery for NPH. BDNF serum concentrations were assessed by a sensitive ELISA kit, and serum concentrations of S-100, NSE and IL-6 were assessed by using ECLIA technology for immunoassay detection. Results Among 15 patients who were included, seven NPH patients were compared to eight control patients. Non-significant decrease in BDNF serum concentrations, an increase of protein S-100 serum concentrations, a decrease of NSE serum concentrations, as well as an increase of IL-6 serum concentrations in NPH patients compared to healthy controls was found. Strong positive correlation between BNDF and Evans index was observed (p=0.0295). Conclusion We did not find a significant difference of BDNF, protein S-100, IL-6 and NSE between serum concentration in NPH and healthy patients. More future research is needed to find the role of BDNF in NPH patients.

The molar ratio between PAI‐1 and BDNF is increased in Alzheimer’s disease patients with full dementia and negatively correlates with MMSE score

AbstractBackgroundIn a previous study, we demonstrated that the enzyme plasminogen activator inhibitor‐1 (PAI‐1), which inhibits plasmin synthesis in the central nervous system (CNS), is increased in the serum of patients with Alzheimer’s disease (AD). In addition to reducing the accumulation of Ab, plasmin in the CNS regulates the synthesis of the trophic factor brain‐derived neurotrophic factor (BDNF) which appears to be altered in the brain of patients with AD. We investigated whether BDNF serum levels in AD and amnestic mild cognitive impairment (aMCI) patients are altered compared to cognitively healthy controls. Moreover, we examined the PAI‐1/BDNF ratio in these patient groups and correlated with cognitive scores as measured by Mini‐Mental State Examination (MMSE).Method40 AD, 40 aMCI and 10 healthy controls were recruited. Venous blood was collected and BDNF serum concentration were quantified by sandwich ELISAs. Comparisons among the experimental groups (AD dementia, aMCI patients, and cognitively healthy controls) on BDNF serum levels were performed using univariate analyses of variance (ANOVA). Pearson correlation coefficients were calculated to explore relationships between biochemical and clinical data. The level of statistical significance was set at p&lt;0.05.ResultThe results showed that BDNF serum levels are decreased in AD as compared to aMCI patients (p &lt; .05). In addition, there was a positive correlation between PAI‐1 and BDNF serum levels (r = .190, p &lt; .05). Furthermore, PAI‐1/BDNF ratio was significantly increased in AD patients as compared to aMCI (p &lt; .001) and controls (p &lt; .001). Lastly, PAI‐1/BDNF ratio negatively correlated with MMSE score (r = ‐.508, p &lt; .001).ConclusionThese data suggest that in AD a reduction of plasmin caused by PAI‐1 may negatively affect the production of BDNF and promote disease progression. Our results also demonstrate that the PAI‐1/BDNF ratio is increased in AD patients compared with aMCI and controls. They also suggest that this ratio could be used as a marker of AD in a state of overt cognitive impairment, as supported by the strong negative correlation between PAI‐1/BDNF ratio and MMSE.

Elevated Brain-Derived Neurotrophic Factor Levels During Depressive Mixed States.

Neurotrophin-like brain-derived neurotrophic factor (BDNF) and pro-inflammatory cytokines may modulate the pathophysiology of mood disorders. Although several studies show alterations in these biomarkers during the depressive, manic, and euthymic states of mood disorders, evidence is lacking for those in a mixed state. Therefore, this study aimed to investigate the relationship between the depressive mixed state (DMX) and peripheral neurobiological factors. We enrolled 136 patients with major depressive episodes. Depressive symptoms were assessed using the Quick Inventory of Depressive Symptomatology Self-Report Japanese version (QIDS-SR-J). The severity of DMX was assessed using the self-administered 12-item questionnaire (DMX-12). Categorical screening as DMX-positive (n=54) was determined by a cutoff score of 13 or more in the specific eight symptoms from the DMX-12; the remaining were DMX-negative (n=82). Serum BDNF, tumor necrosis factor-α, highsensitivity C-reactive protein, and interleukin-6 levels were measured. When comparing biomarkers between the DMX-positive and DMX-negative groups, higher serum BDNF concentration in the DMX-positive group than in the DMX-negative group was the only significant finding (p=0.009). A positive correlation existed between the total score of the eight specific symptoms of DMX-12 and the BDNF concentration (r=0.190, p=0.027). After adjustment for confounders, logistic regression analysis revealed that BDNF (odds ratio [OR]=1.07, 95% confidence interval [CI]=1.00-1.14, p=0.045), bipolar diagnosis (OR=3.43, 95% CI=1.36-8.66, p=0.009), and total QIDS-SR-J score (OR=1.29, 95% CI=1.15-1.43, p<0.001) were significantly associated with DMX positivity. BDNF was positively associated with DMX severity, suggesting that higher BDNF concentrations may be involved in the pathophysiology of DMX.

Interplay between stress, sleep, and BDNF in a high-risk sample of young adults

Children in institutional care have a high risk to experience childhood adversities (CAs), with consequences for physical and mental well-being. The long-term effects of CAs on the brain, including consequences for neuronal plasticity and sleep, are poorly understood. This study examined the interplay between stress (including CAs), sleep, and brain-derived neurotrophic factor (BDNF), a prominent marker for neuronal plasticity. Participants (N = 131, mean age = 26.3±3.4 years, 40 females) with residential youth-care history completed questionnaires measuring CAs (Childhood Trauma Questionnaire, CTQ), psychological well-being (World Health Organization-Five Well-Being Index, WHO-5), and sleep disturbances (Pittsburgh Sleep Quality Inventory, PSQI). Hair cortisol and serum BDNF concentration were measured using enzyme-linked immunosorbent assays. The analyses were conducted by using bootstrap regression models. There was no association of stress parameters or sleep with BDNF concentration. However, we found a significant association of CAs and well-being with sleep disturbances. Last, we found an association between CAs and BDNF in sleep-healthy but not sleep-disturbed participants. Our findings indicated a role of sleep disturbance in the association between stress and BDNF. Still, further studies are warranted using vulnerable groups at-risk to understand long-term effects on mental health and sleep.

Neurotrophin-4 and Brain-Derived Neurotrophic Factor Serum Levels in Renal Transplant Recipients with Chronic Pruritus.

Chronic pruritus (CP) is a common symptom defined as a sensation that provokes the desire to scratch and which lasts for at least 6weeks. CP remains a problem for up to 21.3% of renal transplant recipients (RTRs). Our research aimed to establish the possible association between serum levels of neurotrophin-4 (NT-4) and brain-derived neurotrophic factor (BDNF) and the presence and intensity of CP in RTR. The study was performed on a group of 129 RTRs, who were divided according to the presence or absence of pruritus in the previous 3days. The assessment of pruritus was performed with the use of a numeric rating scale (NRS), 4-Item Itch Questionnaire (4IIQ), and Itchy Quality of Life (Itchy QoL). A total of 129 blood samples with a volume of 9ml were drawn from RTRs during the monthly routine control. Serum levels (pg/mL) of NT-4 and BDNF were measured by the ELISA. Pruritic RTRs have statistically significantly higher serum concentrations of NT-4 serum level compared to non-pruritic RTRs (229.17 ± 143.86pg/mL and 153.08 ± 78.19pg/mL [p = 0.024], respectively). Moreover, a statistically significant difference between pruritic and non-pruritic RTRs with healthy controls was shown (p < 0.001 and p < 0.001, respectively). Although there was a numerically higher serum concentration of BDNF in pruritic RTRs (32.18 ± 7.31pg/mL vs. 31.58 ± 10.84pg/mL), the difference did not reach statistical significance. No statistically significant difference was also seen in BDNF serum levels between RTRs and healthy controls. Furthermore, there was a statistically significant, positive correlation between serum concentration of NT-4 and NRS score (p = 0.008, r = 0.357). The results indicate higher NT-4 serum concentration in RTRs with pruritus compared to RTRs without pruritus. Furthermore, the study revealed a statistically significant, positive correlation between the serum concentration of NT-4 and NRS score.

Brain-derived neurotrophic factor serum concentration and BDNF Val66Met polymorphism in patients with peripheral artery disease: the importance of heart failure

Brain-derived neurotrophic factor serum concentration and BDNF Val66Met polymorphism in patients with peripheral artery disease: the importance of heart failure