Corell, L. | Search bioRxiv

bioRxiv2024

Endurance Exercise Elevates Plasma Mature Brain-Derived Neurotrophic Factor through Child- and Adulthood, with Amplified Effects in Adults

BackgroundBrain-derived neurotrophic factor (BDNF) is a neurotrophin that plays a central role in neuronal health. BDNF exists in two primary isoforms, the mature form (mBDNF) and its precursor (proBDNF), with opposing downstream effects on neuronal function. The positive effect of exercise on plasma levels of the BDNF-isoforms has been extensively studied in adults. However, equivalent investigations are lacking in children and youth. MethodsTwenty healthy children (9-12 years old), 19 adolescents (13-17 years old), and 39 adults (23-49 years old) donated venous blood before and after a 45-minute run. Platelet-poor plasma was analyzed for pro- and mBDNF using enzyme-linked immunosorbent assay. Maximal oxygen uptake and anthropometric data were assessed in all participants, while Tanner stage, circulating sex hormones, and accelerometry-based activity level were assessed in children and adolescents. ResultsWe found that children, adolescents, and adults have similar basal levels of pro-(337-543 pg x ml-1) and mBDNF (650-1111 pg x ml-1). For children and adolescents, basal levels of mBDNF correlated with average time spent in vigorous activity (r=0.5794, p=0.0015). In response to acute endurance exercise, mBDNF increased by 701 {+/-} 946, 1232 {+/-} 1105, and 1557 {+/-} 1168 pg x ml-1 in children, adolescents, and adults, respectively. The acute endurance exercise did not affect proBDNF levels (p>0.05). ConclusionOur results demonstrate that basal plasma pro- and mBDNF levels do not depend on age and maturity. Plasma mBDNF levels increase following endurance exercise in all age groups, but to a greater extent in adults. Highlights/ImpactO_LIWe show that in children and adolescents, regular vigorous physical activity is key to increased basal levels of plasma mBDNF, a factor linked to neuroplasticity and brain health. C_LIO_LIThe ability to elevate mBDNF through exercise is present across all age groups, with the greatest increase in adults. C_LIO_LIThe mBDNF response to physical exercise seems to be independent of underlying physical fitness. C_LIO_LIOur findings suggest that basal plasma mBDNF levels may reflect the cumulative effects of repeated exercise rather than an individuals overall physical fitness. C_LI

physiology↗

bioRxiv2023

Circulating immune cell populations at rest and in response to acute endurance exercise in young adults with cerebral palsy

AimLow physical activity alters immune function and increases the risk of developing chronic inflammation. This cross-sectional study aimed at determining the immune status and function in young adults with cerebral palsy (CP) in comparison to typically developing (TD) individuals. MethodBlood samples from 12 individuals with CP and 17 TD were collected before, immediately after, and one hour following 45 minutes of Frame Running or running, respectively. Independent t-tests were used to compare heart rate, level of exertion, and baseline cell proportions between groups. Mixed model ANOVA was utilized to investigate immune cell responses to exercise across groups. ResultsBaseline levels of TCR{gamma}{delta}+ T-cells were significantly higher in the individuals with CP. Several cell populations showed significant changes after exercise in both CP and TD groups. CD8+ T-cells were only significantly elevated immediately after exercise in the TD participants. Individuals with CP exhibited significantly lower heart rates, despite similar ratings of perceived exertion. InterpretationElevated baseline TCR{gamma}{delta}+ T-cells may indicate low-grade inflammation in adults with CP. Although most of the cell populations showed typical responses to endurance exercise, the absence of response in CD8+ T-cells in individuals with CP may indicate the need for higher intensity during exercise. What this paper addsO_LIThis is the first study addressing immune cells in adults with CP C_LIO_LITCR{gamma}{delta}+ T-cell baseline levels are elevated in adults with CP C_LIO_LIThe CD8+ T-cell response to exercise was blunted in adults with CP C_LIO_LIExercise intensity is decisive for CD8+ T-cell responses in individuals with CP C_LI

immunology↗