Relationship between BDNF rs6265 (VAL66MET) polymorphism and serum BDNF LEVELS in anxiety disorders

association of BDNF Val66Met polymorphism with hPa and saM axis reactivity to psychological and physical stress

Association of BDNF Val66Met polymorphism with clinical severity, cognitive function, and treatment response in schizophrenia

BDNF Val66Met polymorphism was significantly associated with clinical symptom severity, cognitive function, and treatment-related improvement among Acehnese individuals with schizophrenia, and the Val/Val genotype was associated with a more favorable clinical and cognitive profile and stronger early clinical and cognitive response.

Clinical Significance and Changes in Levels of Serum BDNF, mBDNF, AQP4, proBDNF, and GSK3β in Individuals Diagnosed With Bipolar Disorder: A Cross‐Sectional Study

ABSTRACT Background and Aims Bipolar disorder (BD) is a severe mood disorder with unclear pathogenesis and limited diagnostic biomarkers. This study aimed to evaluate serum levels of BDNF, mBDNF, AQP4, proBDNF, and GSK3β between BD patients and healthy controls, and to preliminarily explore their potential clinical significance. Methods Thirty‐seven patients admitted to the Affiliated Hospital of Hangzhou Normal University with BD from November 2023 to September 2025 were selected as the study subjects, while 36 healthy blood donors from the Affiliated Hospital of Hangzhou Normal University, collected in April 2025, were selected as the control subjects to compare serum biomarkers levels of the two groups. Receiver operating characteristic (ROC) curves were plotted to evaluate the diagnostic value of serum biomarkers levels for bipolar disorder. Correlations between serum biomarkers were analyzed between the two groups. Results The results revealed lower levels of BDNF and AQP4 and higher levels of mBDNF, proBDNF and GSK3β in the BD group compared to the healthy control group. Positive correlations were observed between serum BDNF and proBDNF, mBDNF and AQP4, as well as mBDNF and GSK3β levels in the BD group. Combining the serum biomarkers improved diagnostic accuracy compared to using individual serum biomarkers alone. Conclusion In conclusion, patients with BD exhibit elevated serum levels of proBDNF and GSK3β compared to healthy controls, while the levels of BDNF, mBDNF, and AQP4 are significantly lower. These findings suggest that this serum biomarker panel may hold preliminary potential as a supportive indicator for BD. However, given the study's cross‐sectional design and lack of external validation, larger longitudinal cohorts are required to further evaluate its potential clinical significance.

Circulating nerve growth factor as a neuroimmune biomarker in first-episode major depressive disorder: Integrative analysis of serum levels and NGF Ala273Val (rs6330) polymorphism

Background: Major depressive disorder (MDD) has been increasingly recognized as a systemic disorder involving neuroimmune and biochemical dysregulation. Circulating neurotrophic factors, particularly nerve growth factor (NGF), may serve as potential laboratory biomarkers reflecting neurobiological alterations. Methods: This case–control study enrolled 47 drug-naïve patients with first-episode MDD and 40 age- and sexmatched healthy controls. Serum NGF concentrations were quantified using enzyme-linked immunosorbent assay (ELISA). The NGF Ala273Val (rs6330) polymorphism was genotyped via polymerase chain reaction and direct sequencing. Statistical analyses included group comparisons, correlation analysis, and genotype–phenotype association evaluation. Results: Serum NGF levels were significantly elevated in patients with MDD compared with controls (36.81 ± 7.11 vs. 29.74 ± 5.69 pg/mL, P < 0.001). However, no significant correlation was observed between NGF concentrations and HAMD-17 scores (r = 0.12, P = 0.42). Genotype and allele distributions of the NGF Ala273Val polymorphism did not differ significantly between groups (P > 0.05), and no genotype-dependent differences in serum NGF levels were detected. Conclusion: Circulating NGF is significantly altered in first-episode MDD, supporting its role as a neuroimmunerelated biochemical marker associated with disease presence rather than symptom severity. The NGF Ala273Val polymorphism does not appear to influence susceptibility or peripheral NGF expression. These findings highlight the potential utility of serum NGF as a laboratory biomarker in the biochemical characterization of MDD.

Association Between Serum BDNF and S100 B Levels in Community-Dwelling Older Adults.

Population aging has made the maintenance of cognitive function and mental health in older adults a major public health priority. Brain-derived neurotrophic factor (BDNF) and S100 calcium-binding protein B (S100 B) are biomarkers of brain health, reflecting neurotrophic support and neuroinflammatory activity, respectively. The objectives of this study were to examine the association (a) between serum BDNF and S100 B levels and (b) between these biomarkers and cognitive function and depression in community-dwelling older adults. This cross-sectional study included 95 community-dwelling adults aged ≥65 years living in rural Japan. Serum BDNF and S100 B levels were measured using enzyme-linked immunosorbent assays. Cognitive function and depressive symptoms were assessed using four instruments. Spearman's correlation analyses examined associations between the biomarkers and neuropsychological measures. Multiple regression analyses were performed using log10-transformed S100 B as the dependent variable and log10-transformed BDNF, age, sex, education, and BMI as independent variables. Serum BDNF levels were negatively correlated with serum S100 B levels (β = -0.509, p < 0.0001). This association remained significant across adjusted models (all p < 0.0001). Sensitivity analyses yielded consistent results. No associations were observed between serum BDNF or S100 B levels and cognitive function or depression. The inverse relationship between BDNF and S100 B suggests a link between neurotrophic and neuroinflammatory processes. Nursing interventions that enhance BDNF may also affect S100 B level, which may foster brain health in older adults.

Discriminative performance of serum homocysteine in drug-naïve depression: a case-control study with ROC and regression analysis

Depression is a multifactorial disorder involving neurochemical, metabolic, and inflammatory dysregulation. Elevated homocysteine, a marker of impaired one-carbon metabolism, has been implicated in neurotoxicity and oxidative stress pathways associated with depressive pathology. This study evaluated serum homocysteine levels and their association with body mass index (BMI) in patients with incident drug naiive depression compared to healthy controls. This case-control study enrolled 200 participants: 100 patients with newly diagnosed depressive disorder (DSM-5 criteria) and 100 age- and sex-matched healthy controls recruited from a tertiary psychiatry centre in South India. Serum homocysteine was measured using standard enzymatic assay and BMI was calculated from standardised anthropometric measurements. Independent samples t-test, Pearson’s correlation, ROC analysis and Binomial logistic regression analyses were performed. Serum homocysteine was significantly higher in depressed patients than controls (35.8 ± 7.04 µmol/L vs. 13.6 ± 2.48 µmol/L; p  < 0.001, Cohen’s d = 4.193; 95% CI for difference: 20.66–23.58 µmol/L). BMI was also significantly elevated in the depression group (25.67 ± 4.97 kg/m 2 vs. 21.92 ± 2.96 kg/m 2 . p  < 0.001, Cohen’s d = 0.912). A positive homocysteine—BMI correlation was observed in depression( r  = 0.42, p  < 0.001) but not in controls ( r  = 0.04, p  = 0.71). ROC analysis yielded an AUC of 1.000 (optimal cutoff: 20.065 µmol/L, sensitivity: 100%, specificity: 100%), reflecting complete distributional separation in this clinical sample. Binary logistic regression analysis showed homocysteine to be a significant predictor of depression(omnibus χ 2 = 277.26, df = 1, p  < 0.001; 100% classification accuracy; Nagelkerke R 2 = 1.00), though standard odds ratio estimation was precluded by complete separation. Elevated homocysteine and a group-specific BMI—homocysteine correlation were identified in depressed patients. The AUC of 1.000 reflects complete distributional separation in a tightly controlled institutional sample and requires external validation before clinical application. As folate, vitamin B12, and lifestyle confounders were unmeasured, findings are hypothesis-generating and warrant prospective multicentre validation.