Document Type
Journal Article
Publication Title
GeroScience
Publisher
Springer
School
School of Medical and Health Sciences
RAS ID
69883
Funders
Open Access funding enabled and organized by CAUL and its Member Institutions / National Health and Medical Research Council
Grant Number
NHMRC Number : GNT1097105
Grant Link
http://purl.org/au-research/grants/nhmrc/1097105
Abstract
Physical activity is a promising preventative strategy for Alzheimer’s disease: it is associated with lower dementia risk, better cognition, greater brain volume and lower brain beta-amyloid. Blood-based biomarkers have emerged as a low-cost, non-invasive strategy for detecting preclinical Alzheimer’s disease, however, there is limited literature examining the effect of exercise (a structured form of physical activity) on blood-based biomarkers. The current study investigated the influence of a 6-month exercise intervention on levels of plasma beta-amyloid (A 42, A 40, A 42/40), phosphorylated tau (p-tau181), glial fibrillary acidic protein (GFAP) and neurofilament light (NfL) chain in cognitively unimpaired older adults, and as a secondary aim, whether blood-based biomarkers related to cognition. Ninety-nine community-dwelling older adults (69.1 ± 5.2) were allocated to an inactive control, or to moderate or high intensity exercise groups where they cycled twice weekly for six months. At baseline and six months (post-intervention), fasted blood was collected and analysed using single molecule array (SIMOA) assays, and cognition was assessed. Results demonstrated no change in levels of any plasma biomarker from pre- to post-intervention. At baseline, higher NfL was associated with poorer cognition ( = -0.33, SE = 0.13, adjusted p =.042). Exploratory analyses indicated higher cardiorespiratory fitness was associated with higher NfL and GFAP levels in apolipoprotein E (APOE) 4 non-carriers compared to 4 carriers (NfL, = -0.43, SE = 0.19, p =.029; GFAP, = -0.41, SE = 0.20, p =.044), though this association was mediated by body mass index (BMI). These results highlight the importance of considering BMI in analysis of blood-based biomarkers, especially when investigating differences between APOE ε4 carriers and non-carriers. Our results also indicate that longer follow-up periods may be required to observe exercise-induced change in blood-based biomarkers.
DOI
10.1007/s11357-024-01130-2
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Sewell, K. R., Rainey-Smith, S. R., Pedrini, S., Peiffer, J. J., Sohrabi, H. R., Taddei, K., . . . Brown, B. M. (2024). The impact of exercise on blood-based biomarkers of Alzheimer’s disease in cognitively unimpaired older adults. GeroScience. Advance online publication. https://doi.org/10.1007/s11357-024-01130-2