Resisting Vascular Cognitive Impairment: The Effects of Resistance Training on Myelin and Blood-based Biomarkers of Neuroplasticity in Older Adults

We are studying if strength training exercises can reduce myelin loss and preserve cognitive abilities in adults with cognitive impairment due to vascular risk factors (e.g., high blood pressure), also known as vascular cognitive impairment (VCI).

Worldwide, VCI is the second most common cause of dementia and it is associated with myelin loss. Myelin is a component of neurons critical for transmission of brain signals. Thus, myelin is important for the maintenance of cognitive (i.e., thinking) abilities. Animal studies suggest myelin loss may be minimized with physical exercise. The objective is to determine whether strength training (e.g., lifting weights) is an effective strategy for slowing down myelin loss in persons with VCI.

We will conduct a 12-month study with 88 adults with VCI; half will receive strength training and half will receive balance and stretching exercises. At the end of study, the two groups will be compared on myelin content and cognitive function. Reducing myelin loss could preserve cognitive abilities in adults with VCI and reduce their risk of dementia. Our proposal is also timely as the prevalence and burden of VCI will only increase with the world’s aging population.


End of Award Update – May 2024

Results:
Our main goal in this project was to measure the effect of resistance exercise (e.g., lifting weights) on myelin levels in the white matter. Myelin is the fatty tissue layer that covers axons in the white matter of brain, which is related to faster neuronal signal transmission. Myelin loss is very common in older adults living with cerebral small vessel disease. This condition causes a series alterations in the white matter, which may lead to declines in brain functioning and increase dementia risk. We first showed that higher levels of physical activity (e.g., waking, gardening, etc) were associated with greater levels of myelin in a few important structures in the white matter, including a region called corpus callosum in people with cerebral small vessel disease. We then tested whether 12 months of  the exercise program, resulting in no major changes in myelin. We compared resistance training group to a balance, stretching and toning group. Contrary to our hypothesis, the resistance group did not lead to changes in myelin, but the balance, toning and stretching group resulted in greater myelin levels measured in the deep white matter of the brain. This indicated that for these deep regions, including the fornix and corpus callosum, an exercise program focusing on balance, toning and stretching exercise may benefit myelin. The effects of resistance exercise may be more visible in other regions, which we have not yet looked in this study. Candidate regions include those that are linked with important cognitive abilities, such as the anterior cingulate cortex. I am currently investigating changes in these regions.
Impact:
Our research so far has received good attention from the scientific community, with two papers from the project being published in high-quality journals. I have also been able to present the findings from our work at international meetings, wherein I had the opportunity to exchange knowledge and gain new ideas for future projects.
Potential Influence:
The support I received from Health Research BC on this project allowed me to grow as a researcher, teacher, and mentor. The knowledge gained, connections formed, and experiences collected have been crucial in shaping the next steps in my career. This award provided me with the unique opportunity to work with and learn from an internationally recognized researcher and inspiring mentor in Dr. Teresa Liu-Ambrose and incredible co-mentors like Dr. Roger Tam. I also formed meaningful friendships with lab mates and very productive collaborations with colleagues at UBC, across Canada, and at international institutions from places like the US, Germany, and Spain. The Health Research BC award was instrumental in completing my postdoctoral fellowship and will have a long-lasting impact on my career. I am hoping to soon start my own research lab and continue investigating the role of exercise and other lifestyle interventions in promoting brain health and overall healthy aging.
Next Steps:
I will continue to investigate the impact of exercise on myelin and other clinically meaningful outcomes in people with cerebral small vessel disease, working alongside Dr. Liu-Ambrose and Tam at UBC. We are organizing the knowledge translation activities at UBC such as the Brain Health Symposium to take place in the summer. Our work will also be showcased at upcoming Alzheimer’s Association International Conference in Philadelphia. I will present on findings from my postdoctoral research at a Featured Research Session as well as in a Perspective Session, which Dr. Liu-Ambrose and I organized with colleagues from Spain and the US.