👤 Emilia Main

Brain-derived neurotrophic factor (BDNF) is a protein crucial to the survival, growth, and differentiation of neurons in the brain and spinal cord. BDNF is monitored across many populations as an indicator of one's cardiometabolic disease (CMD) and mental health (MH) risk. Adults living with a traumatic spinal cord injury (tSCI) are at a higher risk of developing CMD and MH issues, with symptoms often going unrecognized. Establishing serum BDNF as a screening tool within the tSCI population has the potential to improve CMD and MH symptom recognition. This systematic review aims to: (1) explore the tSCI literature to determine whether an association exists between serum BDNF, MH, and CMD risk(s); and; (2) identify best-practice BDNF sampling techniques within the tSCI population. A comprehensive search strategy was developed in collaboration with a University Health Network Librarian. Six databases (MEDLINE, Embase, CENTRAL, APA PsycInfo, CINAHL Ultimate, and Web of Science Core Collection) were searched to identify English-language studies published from inception to July 2025. Studies which reported serum BDNF in the tSCI population in addition to either MH or CMD and have three or more human participants with acute or chronic tSCI were included. Duplicate abstracts were removed and the remaining titles and abstracts reviewed and selected for full-text screening. Study quality was assessed for potential risk of bias using Downs and Black Checklist (Clinical Trials), Newcastle-Ottawa Score (Case-Control Study), or Joanna Briggs Institute Checklist (Cross-sectional Study), prior to data extraction. The serum BDNF analytic methods were reviewed in detail. A total of 2,148 potential studies were identified via the searches, of which 631 duplicates were removed, 1,488 abstracts were excluded for inappropriate population, outcome measure, or study design, and 29 articles were selected for full-text screening, with four studies included in the final review. All studies sampled and analyzed serum BDNF. A total of 271 participants (AIS: A-D, NLI: C1-L5), predominantly male (n = 224), with acute (n = 165) and chronic (n = 51) injuries aged 14-75 as well as healthy controls (n = 55) were included. One study investigated the influence of an intervention and three studies were cross-sectional. No identified study included a description or indication of the prevalence for MH conditions or CMD risk factors. Based on the reviewed literature, links between serum BDNF and MH disorders or CMD risk have not yet been established for individuals with acute or chronic tSCI. The selected studies demonstrated no consistent sampling or analysis methods, with limited adherence to prior established standards in the general population, bringing into question the reliability, validity, and quality of the available outcome data. Show less

Identifying strategies to mitigate age-associated cognitive decline is crucial. High-velocity power training enhances physical function in older adults and cognitive training has mixed cognitive benefits, however the combined effects of these interventions remain uncertain. This 18-month cluster randomized controlled trial investigated whether dual-task functional power training (DT-FPT) enhances cognition in older adults and assessed if responses differ by apolipoprotein-E and brain-derived neurotrophic factor (BDNF) polymorphisms. Twenty-two independent-living retirement communities (300 residents, ≥65y at increased falls risk) were randomized to 12-months of group-based DT-FPT (6-months supervised +6-months maintenance, 45-60 minutes, 2/week) performed simultaneously with cognitive and/or motor tasks, followed by 6-months follow-up, or usual care control (CON). Cognitive domains were assessed using CogState at baseline, 6, 12 and 18-months. Z-scores were created to form composites for psychomotor-attention, learning-working memory and global cognition. BDNF and APOE polymorphism data were obtained from blood samples. Overall, 223 (74%) participants completed the 18-month intervention; mean exercise adherence was 50% at 6-months and 40% at 12-months. Net benefits in choice reaction time and attention (0.17 SD, P = 0.016), psychomotor-attention (0.19 SD, P = 0.029), and a composite of psychomotor-attention, learning-working memory (0.11 SD, P = 0.046) were detected in DT-FPT vs CON after the 6-month supervised phase. At 12 and 18 months, benefits from DT-FPT relative to CON were extended to visual learning (0.29 SD, P = 0.013; 0.27 SD, P = 0.008) and learning-working memory (0.13 SD, P = 0.047; 0.18 SD, P = 0.013). CON exhibited a 0.19 SD net benefit for executive function (P = 0.003) after 18 months. BDNF Met carriers at 18 months showed improved working memory (0.35 SD, P = 0.042) and learning-working memory (0.37 SD, P = 0.011) in DT-FPT versus CON. In older retirement living residents, DT-FPT may improve cognitive domains critical for functional independence, with genotype potentially influencing these outcomes.Australian New Zealand Clinical Trials Registry (ACTRN12613001161718). This project was funded by the National Health and Medical Research Council (NHMRC) (APP1046267). Show less

17β-hydroxysteroid dehydrogenase 3 (17β-HSD3) deficiency results in insufficient biosynthesis of testosterone and consequently dihydrotestosterone. This is important for the fetal development of male genitalia. Thus, most 46,XY patients with 17β-HSD3 deficiency have a female appearance at birth and present with virilization at puberty. This study presents the differences in the clinical and hormonal data and analyses of gonadal characteristics in two siblings with 17β-HSD3 deficiency. Patient 1 presented with deepening of the voice and signs of virilization at puberty and increased serum levels of testosterone (T) of 10.9 nmol/L (2.9 SDS) and androstenedione (Δ4) of 27 nmol/L (3.3 SDS) were observed. The T/Δ4-ratio was 0.39. Patient 2 was clinically prepubertal at the time of diagnosis, but she also had increased levels of T at 1.97 nmol/L (2.9 SDS), Δ4 at 5 nmol/L (3.3 SDS), and the T/Δ4-ratio was 0.40, but without signs of virilization. Both siblings were diagnosed as homozygous for the splice-site mutation c.277+4A>T in intron 3 of Two siblings with 17β-HSD3 deficiency differed in pubertal development at the time of diagnosis and showed marked differences in their clinical presentation, hormonal profile, gonadal morphology and expression of cell lineage markers. Early diagnosis of 17β-HSD3 deficiency appears beneficial to ameliorate long-term consequences. Show less