Search Results (34)

Brain-derived neurotrophic factor (BDNF) is associated with nicotine use behaviours, the intensity of nicotine cravings, and the experience of withdrawal symptoms. Given the established influence of sex, brain-derived neurotrophic factor variants, personality traits and anxiety levels on nicotine use, this study aimed to conduct a comprehensive association analysis of these factors within a cohort of women who use nicotine. The study included 239 female participants: 112 cigarette users (mean age = 29.19, SD = 13.18) and 127 never-smokers (mean age = 28.1, SD =10.65). Study participants were examined using the NEO Five-Factor Inventory and the State–Trait Anxiety Inventory. Genotyping of rs6265, rs10767664, and rs2030323 was performed by real-time PCR using an oligonucleotide assay. We did not observe significant differences in the distribution of either genotype or allele of rs6265, rs10767664 and rs2030323 between groups. However, compared to the never-smokers, cigarette users scored significantly lower on the Agreeableness (5.446 vs. 6.315; p = 0.005767; d_Cohen’s = 0.363; η² = 0.032) and the Conscientiousness (5.571 vs. 6.882; p = 0.000012; d_Cohen’s = 0.591; η²= 0.08) scales. There was significant linkage disequilibrium between all three analysed polymorphic variants—between rs6265 and rs10767664 (D′ = 0.9994962; p < 2.2204 × 10⁻¹⁶), between rs6265 and rs2030323 (D′ = 0.9994935; p < 2.2204 × 10⁻¹⁶) and between rs10767664 and rs20330323 (D′ = 0.9838157; p < 2.2204 × 10⁻¹⁶), but the haplotype association analysis revealed no significant differences. While our study did not reveal an association between the investigated brain-derived neurotrophic factor polymorphisms (rs6265, rs10767664 and rs2030323) and nicotine use, it is essential to acknowledge that nicotine dependence is a complex, multifactorial phenotype. Our study expands the current knowledge of BDNF ’s potential role in addictive behaviours by exploring the understudied variants (rs10767664 and rs2030323), offering a novel contribution to the field and paving the way for future research into their functional relevance in addiction-related phenotypes. The lower Agreeableness and Conscientiousness scores observed in women who use nicotine compared to never-smokers suggest that personality traits play a significant role in nicotine use in women. The observed relationship between personality traits and nicotine use lends support to the self-medication hypothesis, suggesting that some women may initiate or maintain nicotine use as a coping mechanism for stress and negative affect. Public health initiatives targeting women should consider personality and psychological risk factors in addition to biological risks. Full article

Dysregulated inflammatory processes contribute to depression, and gene–environment interactions may influence an individual’s risk and resilience. Reduced brain-derived neurotrophic factor (BDNF) expression increases susceptibility for developing depressive symptoms, and the Val66Met (rs6265) single-nucleotide polymorphism (SNP) on the BDNF gene is linked to mood disorders. However, whether Val66Met confers increased vulnerability to inflammation-induced depressive tendencies is unknown. Here, we tested the hypothesis that the Val66Met SNP increases vulnerability to inflammation-induced depressive symptoms in a mouse model of lipopolysaccharide (LPS)-induced depression-like behavior. Behavior and neuroinflammation, following a 24 h LPS challenge, were measured in mice expressing the human BDNF Val66Met gene variant or Val66Val littermates (control). The Val66Met genotype did not affect the peripheral inflammatory response, acute neuroinflammation, or the acute sickness behavior response. Val66Met mice exhibited anhedonia-like behavioral responses following LPS challenge, and we found increased mRNA expression of IL-1β and TNFα in the cerebrum compared to controls. The mRNA expression of IL-1β and TNFα in the hippocampus and the nucleus accumbens of Val66Met mice was increased following LPS, and a significant genotype × LPS interaction was detected for CD68 expression in the nucleus accumbens. In summary, these data suggest that immune activation in Val66Met mice increased susceptibility to anhedonic behavior and dysregulated negative regulation of inflammation. Full article

Background: Bipolar disorder (BD) is a chronic condition associated with treatment resistance, cognitive decline, structural brain changes, and an approximately 13-year reduction in life expectancy compared to the general population. Depression in BD substantially impairs quality of life, while neuroinflammation and excitotoxicity are thought to contribute to the recurrence of mood episodes and disease progression. Brain-derived neurotrophic factor (BDNF) plays a key role in neuronal growth and function, with its dysregulation being linked to various psychiatric disorders. This study is an extension of a previously published clinical trial and was conducted to assess the effects of three BDNF and BDNF-AS gene polymorphisms (rs1519480, rs6265, and rs10835210) on treatment outcomes and serum BDNF levels in patients with treatment-resistant bipolar disorder depression (TRBDD) over an eight-week period. Methods: This study included 41 participants from a previously conducted randomized clinical trial, all of whom had available BDNF serum samples and genotype data. The participants, aged 21 to 65, were diagnosed with bipolar disorder, and treatment-resistant depression was assessed using the Maudsley Staging Method. Participants were randomly assigned to receive either escitalopram plus a placebo (ESC+PBO) or escitalopram plus celecoxib (ESC+CBX) over an 8-week period. Statistical analyses included a mixed ANOVA and chi-square tests to compare the minor allele carrier status of three SNPs with treatment response and remission rates. Results: Non-carriers of the rs6265 A allele (p = 0.005) and carriers of the rs10835210 A allele (p = 0.007) showed a significantly higher response to treatment with adjunctive celecoxib compared to escitalopram alone. Additionally, remission rates after adjunctive celecoxib were significantly higher in both carriers and non-carriers across all three SNPs compared to escitalopram alone. However, remission rates were notably higher in non-carriers of the rs1519480 G allele and rs10835210 A allele, as well as in carriers of the rs6265 A allele. Conclusions: This study suggests that genetic variations in BDNF and BDNF-AS genes significantly influence treatment response to and remission with escitalopram and celecoxib in bipolar disorder. Full article

Obesity represents a complex interplay between genetics, nutrition, and lifestyle. This study aimed to elucidate the intricate relationship between genetic variants, energy intake, and bioactive compounds in influencing obesity risk, particularly in low energy intake, to reveal how dietary intake modulates molecular-level interactions. We analyzed 53,117 participants stratified by obesity status and energy intake levels. Genome-wide association studies explored the genetic variants associated with obesity risk in low-energy- and high-energy-intake subgroups. Advanced computational approaches, including molecular docking, k-means clustering, and uniform manifold approximation and projection (UMAP), were employed to analyze interactions between missense variants and natural compounds. Ten genetic variants were significantly associated with obesity, particularly in participants with low energy intake. The most prominent variants included brain-derived neurotrophic factor (BDNF) Val66Met polymorphism (rs6265). Molecular docking identified 152 bioactive compounds with strong binding affinity to BDNF Val66Met, including 107 compounds binding to both wild and mutant types. Citrus fruits and green vegetables showed selective binding to the mutant type. Antioxidant nutrient intake (anthocyanins, isoflavonoids, vitamins C and E, selenium) was higher in lean versus obese individuals in the high-energy-intake group. Alcohol consumption and selenium intake modulated polygenic risk scores’ influence on obesity risk in high-energy-intake individuals. Notably, citrus fruit intake correlated with lower BMI across all BDNF rs6265 genotypes. In conclusion, energy intake-specific genetic associations with obesity and identifies potential bioactive compounds for targeted interventions. The findings suggest that antioxidant nutrient intake, particularly from citrus fruits, may help manage obesity risk, especially in individuals with specific genetic variants. Full article

Retinal neurodevelopment, vascularization, homeostasis, and stress response are influenced by factors such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tyrosine hydroxylase (TH), and erythropoietin (EPO). As retinopathy of prematurity (ROP) is a neurovascular retinal disease, this study analyzed the contributions of NGF (rs6330), BDNF (rs7934165), TH (rs10770141), and EPO (rs507392) genetic functional polymorphisms to the modulation of hematological and biochemical parameters of the first week of life and their association with ROP development. A multicenter cohort of 396 preterm infants (gestational age < 32 weeks or birth weight < 1500 g) was genotyped using MicroChip DNA and iPlex MassARRAY^® platform. Multivariate regression followed univariate assessment of ROP risk factors. NGF (GG) genotype was associated with a higher ROP risk (OR = 1.79), which increased further (OR = 2.38) when epistatic interactions with TH (allele C) and BDNF (allele G) were present. Significant circulating biomarker differences, including bilirubin, erythrocytes, monocytes, neutrophils, lymphocytes, and platelet markers, were found between ROP and non-ROP groups, with variations depending on the polymorphism. These findings suggest that NGF (rs6330) and its interactions with related genes contribute to ROP risk, providing valuable insights into the genetic and biological mechanisms underlying the disease and identifying potential predictive biomarkers. Full article

Gliomas are the most common and lethal forms of malignant brain tumors. We attempted to identify the role of the aging-suppressor Klotho gene and Klotho protein in the immunopathogenesis of gliomas. We examined Klotho genetic variants by PCR-RFLP and measured serum Klotho levels using the ELISA method. We found a statistically significantly increased frequency of rs1207568A allele and rs1207568 GA genotypes in co-dominant, dominant and over-dominant models in grade IV as compared to grade II and III glioma patients. The levels of soluble α Klotho (sαKL) were significantly lower in grade III and IV glioma patients than in healthy controls (p = 0.034; 0.0083). Patients with sαKL levels above 2500 pg/mL survived significantly longer than patients with sαKL below 2500 pg/mL (p = 0.038). We also found a positive correlation of the serum levels of sαKL with seven biomarkers, like angiogenic vascular endothelial growth factor (p = 0.0008), chemokine fractalkine (p = 0.0009), interferon γ (p = 0.003), glial derived neurotrophic factor (p = 0.0268), pro-inflammatory and pro-Th1 cytokine IL-6 (p = 0.0347), anti-inflammatory, pro-Th2 cytokines IL-4 (p = 0.0037) and IL-13 (p = 0.0004). Our results suggest the impact of Klotho genetic variants and Klotho levels on advanced-grade glioma. Full article

Background/Objectives: The biological basis for behavioral manifestations of Alzheimer’s disease remains unclear. Emotional and behavioral alterations of Alzheimer’s disease can result in substantial caregiver burden and lack effective management. This study expands upon previous work investigating behavioral alterations in mice with Alzheimer’s disease and a potential treatment of increasing brain-derived neurotrophic factor (BDNF) using repetitive transcranial magnetic stimulation (rTMS). Methods: A total of 47 3xTg-AD (Alzheimer’s) and 53 B6 (wildtype) mice were administered ANA12 (an antagonist of TrkB receptor) or Vehicle (saline) and then rTMS or Sham treatment daily. After 14 days of treatments and injections, mouse behavior was assessed under various behavioral cognitive tests. Mice were then perfused, and brain samples were processed for histology and protein assays. Brain homogenates were analyzed for BDNF and its downstream signaling molecules. Results: Open field testing demonstrated that 3xTg-AD mice spent more time in the center than B6 mice. 3xTg-AD-Sham mice injected with ANA12 were the only group to travel significantly less distance than B6-ANA12-Sham or B6-Vehicle-Sham mice (p < 0.05), while 3xTg-AD-rTMS mice (irrespective of injection) were not significantly different from B6 mice. 3xTg-AD mice had significantly greater measured levels of BDNF and TrkB than the wild-type mice. Conclusions: Treatment of Alzheimer’s disease using rTMS positively affects elements of hypoactivity, but not all behavioral abnormalities. rTMS shifted 3xTg-AD open field behavioral test measures, generating significant differences between untreated 3xTg-AD and B6 genotypes. Despite its benefit, further investigation of rTMS as a treatment for Alzheimer’s disease as well as its biological underpinnings are needed. Full article

Brain-derived neurotrophic factor (BDNF) is a potential biomarker of response to treatment in psychiatric disorders. As it plays a role in the pathophysiological development of schizophrenia and bipolar disorder, it is of interest to study its role in predicting therapeutic responses in both conditions. We carried out a systematic review of the literature, looking for differences in baseline BDNF levels and the Val66Met BDNF polymorphism in these disorders between responders and non-responders, and found information showing that the Val/Val genotype and higher baseline BDNF levels may be present in patients that respond successfully to pharmacological and non-pharmacological treatments. However, there is still limited evidence to support the role of the Val66Met polymorphism and baseline BDNF levels as predictors of treatment response. Full article

Stress is an important risk factor for the onset of anxiety and depression. The ability to cope with stressful events varies among different subjects, probably depending on different genetic variants, sex and previous life experiences. The Val66Met variant of Brain-Derived Neurotrophic Factor (BDNF), which impairs the activity-dependent secretion of BDNF, has been associated with increased susceptibility to the development of various neuropsychiatric disorders. Adult male and female wild-type Val/Val (BDNF^V/V) and heterozygous Val/Met (BDNF^V/M) mice were exposed to two sessions of forced swimming stress (FSS) per day for two consecutive days. The mice were behaviorally tested 1 day (short-term effect) or 11 days (long-term effect) after the last stress session. Protein and mRNA levels were measured in the hippocampus 16 days after the end of stress exposure. Stressed mice showed a higher anxiety-like phenotype compared to non-stressed mice, regardless of the sex and genotype, when analyzed following the short period of stress. In the prolonged period, anxiety-like behavior persisted only in male BDNF^V/M mice (p < 0.0001). Interestingly, recovery in male BDNF^V/V mice was accompanied by an increase in pCREB (p < 0.001) and Bdnf4 (p < 0.01) transcript and a decrease in HDAC1 (p < 0.05) and Dnmt3a (p = 0.01) in the hippocampus. Overall, our results show that male and female BDNF Val66Met knock-in mice can recover from subchronic stress in different ways. Full article

We review emerging preclinical and clinical evidence regarding brain-derived neurotrophic factor (BDNF) protein, genotype, and DNA methylation (DNAm) as biomarkers of outcomes in three important etiologies of pediatric acquired brain injury (ABI), traumatic brain injury, global cerebral ischemia, and stroke. We also summarize evidence suggesting that BDNF is (1) involved in the biological embedding of the psychosocial environment, (2) responsive to rehabilitative therapies, and (3) potentially modifiable. BDNF’s unique potential as a biomarker of neuroplasticity and neural repair that is reflective of and responsive to both pre- and post-injury environmental influences separates it from traditional protein biomarkers of structural brain injury with exciting potential to advance pediatric ABI management by increasing the accuracy of prognostic tools and informing clinical decision making through the monitoring of therapeutic effects. Full article

Substance addiction is a neuropsychiatric disorder characterized by a recurring desire to continue using a substance despite harmful consequences. Brain-derived neurotrophic factor (BDNF) is a protein that plays a role in the activity-dependent remodeling of neural function in adult nervous systems. This study analyzed the association of the rs6265 polymorphism of the BDNF gene in a group of patients addicted to psychoactive substances who were participating in addiction treatment for the first time, in a group of post-relapse psychoactive substance abusers and in a control group. The study also assessed personality and anxiety in all study groups. Statistically significant differences in the frequency of genotypes and alleles were found between all study groups. Compared to the control, both study groups had statistically significantly higher scores for trait and state anxiety. Addicted patients in both groups also had higher scores on the Neuroticism and Openness scales and lower scores on the Extraversion and Agreeableness scales. The results of this study provide further evidence that personality traits, anxiety and the rs6265 polymorphism of the BDNF gene may be risk factors for susceptibility to addiction to psychoactive substances. In addition, they can be a predictor of addiction relapse, but further extensive studies are required to confirm these findings. Full article

Background: The brain–heart axis is an intra- and bidirectional complex that links central nervous system dysfunction and cardiac dysfunction. In recent decades, brain-derived neurotrophic factor (BDNF) has emerged as a strategic molecule involved in both brain and cardiovascular disease (CVD). This systematic review of systematic reviews aimed to (1) identify and summarize the evidence for the BDNF genotype and BDNF concentration in CVD risk assessment, (2) evaluate the evidence for the use of BDNF as a biomarker of CVD recovery, and (3) evaluate rehabilitation approaches that can restore BDNF concentration. Methods: A comprehensive search strategy was developed using PRISMA. The risk of bias was assessed via ROBIS. Results: Seven studies were identified, most of which aimed to evaluate the role of BDNF in stroke patients. Only two systematic reviews examined the association of BDNF concentration and polymorphism in CVDs other than stroke. Conclusions: The overall evidence showed that BDNF plays a fundamental role in assessing the risk of CVD occurrence, because lower BDNF concentrations and rs6265 polymorphism are often associated with CVD. Nevertheless, much work remains to be carried out in current research to investigate how BDNF is modulated in different cardiovascular diseases and in different populations. Full article

Despite the increasing availability of antidepressant drugs, a high rate of patients with major depression (MDD) does not respond to pharmacological treatments. Brain-derived neurotrophic factor (BDNF)-tyrosine receptor kinase B (TrkB) signaling is thought to influence antidepressant efficacy and hippocampal volumes, robust predictors of treatment resistance. We therefore hypothesized the possible role of BDNF and neurotrophic receptor tyrosine kinase 2 (NTRK2)-related polymorphisms in affecting both hippocampal volumes and treatment resistance in MDD. A total of 121 MDD inpatients underwent 3T structural MRI scanning and blood sampling to obtain genotype information. General linear models and binary logistic regressions were employed to test the effect of genetic variations related to BDNF and NTRK2 on bilateral hippocampal volumes and treatment resistance, respectively. Finally, the possible mediating role of hippocampal volumes on the relationship between genetic markers and treatment response was investigated. A significant association between one NTRK2 polymorphism with hippocampal volumes and antidepressant response was found, with significant indirect effects. Our results highlight a possible mechanistic explanation of antidepressant action, possibly contributing to the understanding of MDD pathophysiology. Full article

Genetics researchers increasingly combine data across many sources to increase power and to conduct analyses that cross multiple individual studies. However, there is often a lack of alignment on outcome measures when the same constructs are examined across studies. This inhibits comparison across individual studies and may impact the findings from meta-analysis. Using a well-characterized genotypic (brain-derived neurotrophic factor: BDNF) and phenotypic constructs (working memory and reading comprehension), we employ an approach called Rosetta, which allows for the simultaneous examination of primary studies that employ related but incompletely overlapping data. We examined four studies of BDNF, working memory, and reading comprehension with a combined sample size of 1711 participants. Although the correlation between working memory and reading comprehension over all participants was high, as expected ($\rho$ = 0.45), the correlation between working memory and reading comprehension was attenuated in the BDNF Met/Met genotype group ($\rho$ = 0.18, n.s.) but not in the Val/Val ($\rho$ = 0.44) or Val/Met ($\rho$ = 0.41) groups. These findings indicate that Met/Met carriers may be a unique and robustly defined subgroup in terms of memory and reading comprehension. This study demonstrates the utility of the Rosetta method when examining complex phenotypes across multiple studies, including psychiatric genetic studies, as shown here, and also for the mega-analysis of cohorts generally. Full article

The aim of the present study was to gain a better understanding of the role of brain-derived neurotrophic factor (BDNF) and dopamine D3 receptors in the effects of chronic methamphetamine (METH) on prepulse inhibition (PPI), an endophenotype of psychosis. We compared the effect of a three-week adolescent METH treatment protocol on the regulation of PPI in wildtype mice, BDNF heterozygous mice (HET), D3 receptor knockout mice (D3KO), and double-mutant mice (DM) with both BDNF heterozygosity and D3 receptor knockout. Chronic METH induced disruption of PPI regulation in male mice with BDNF haploinsufficiency (HET and DM), independent of D3 receptor knockout. Specifically, these mice showed reduced baseline PPI, as well as attenuated disruption of PPI induced by acute treatment with the dopamine receptor agonist, apomorphine (APO), or the glutamate NMDA receptor antagonist, MK-801. In contrast, there were no effects of BDNF heterozygosity or D3 knockout on PPI regulation in female mice. Chronic METH pretreatment induced the expected locomotor hyperactivity sensitisation, where female HET and DM mice also showed endogenous sensitisation. Differential sex-specific effects of genotype and METH pretreatment were observed on dopamine receptor and dopamine transporter gene expression in the striatum and frontal cortex. Taken together, these results show a significant involvement of BDNF in the long-term effects of METH on PPI, particularly in male mice, but these effects appear independent of D3 receptors. The role of this receptor in psychosis endophenotypes therefore remains unclear. Full article