Breakthrough study shows how exercise protects against Alzheimer’s and Parkinson’s

Accumulating evidence shows that exercise can improve brain function and delay or prevent the onset of neurodegenerative diseases. (Credit: Shutterstock Images)

Accumulating evidence shows that exercise can improve brain function and delay or prevent the onset of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Although the underlying mechanisms remain unclear, recent research suggests that exercise-induced activation of peripheral systems such as muscle, gut, liver, and adipose tissue may influence neuronal plasticity.

A special issue of Brain Plasticity presents new research and findings on neuronal plasticity and the role of peripheral factors in cognitive health.

“At least a dozen peripheral factors have been identified influencing neurotrophin levels, adult neurogenesis, inflammation, synaptic plasticity, and memory function,” explained co-guest editor and journal editor-in-chief Henrietta van Praag, Ph.D., Charles E. Schmidt. College of Medicine and Florida Atlantic University Brain Institute.

Cathepsin B (CTSB), myokine, and brain-derived neurotrophic factor (BNDF) have been found to have strong neuroprotective effects. In a new study presented in a special issue, researchers examined whether increasing the intensity of aerobic exercise would lead to an increase in the amount of CTSB and BDNF circulating in the blood. Sixteen young healthy subjects performed aerobic exercises on a treadmill at maximum load, and then at 40%, 60% and 80% of power.

Similar stories

Circulating CTSB and BDNF were measured in blood samples taken after each exercise, and CTSB, BDNF and mRNA protein expression was measured in skeletal tissue. Researchers have found that high-intensity exercise increases circulating CTSB in young adults immediately after exercise, and that skeletal muscle tissue expresses both the message and protein CTSB and BDNF.

“CTSB and BDNF are promising therapeutic targets that can delay the onset and progression of cognitive impairment,” said lead researcher Jacob M. House, Ph.D., University of Michigan School of Kinesiology. “Further studies are needed to elucidate the mechanisms governing their release, processing, and the specific role of fibers in skeletal muscle tissue.”

The special issue also highlights new research that suggests that CTSB may play a role in cognitive control by modulating processing speed, and that both moderate and high-intensity interval exercise improves serum BDNF and working memory performance in young adult women.

In response to various stimuli, skeletal muscles can interact with the central nervous system (CNS) in various ways. Regulated processes include improved cerebral blood flow, brain metabolic functions, mitochondrial biogenesis, and neurogenesis, while protective signaling reduces oxidative stress, cell aging, and neuroinflammation. In general, the effect of muscle-brain signals on these cellular processes improves cognitive functions. (Credit: Credit: Mamta Rai and Fabio Demontis, Brain Plasticity)

Five review articles cover inter-organ crosstalk between muscle, liver, adipose tissue, gut microbiome, and brain. Although exercise is well known to protect the central nervous system, it has only recently been discovered that it depends on the endocrine capacity of skeletal muscles.

In their review, co-authors Mamta Rai, Ph.D., and Fabio Demontis, Ph.D., both from the Department of Developmental Neuroscience at St. Jude Children’s Research Hospital, highlight the influence of myokines, metabolites, and other non-traditional factors that mediate muscle effects. – the connection between the brain and retinal muscles in neurogenesis, neurotransmitter synthesis, proteostasis, mood, sleep, cognitive function and eating behavior after exercise.

They also raise the possibility that harmful myokines resulting from muscle inactivity and disease states could become a new avenue for therapeutic intervention. “We hypothesize that adaptation of muscle signaling to the central nervous system by modulating myokines and myometabolites may combat age-related neurodegeneration and brain diseases that are affected by systemic signals,” they said.

Men and women show differences in their biological responses to physical activity, as well as in their vulnerability to the onset, progression, and outcomes of neurodegenerative disease.

A review by co-authors Constanza J. Cortes, Ph.D., University of Alabama at Birmingham, and Zurin De Miguel, Ph.D., California State University, discusses new research on sex differences in immune system response to exercise as a potential mechanism for which physical activity influences brain.

“Anecdotal evidence suggests that the immune response to exercise may be enhanced in women, but more research is needed,” said Dr. Cortes and Dr. De Miguel. “Interdisciplinary research is needed, integrating neuroscience, exercise physiology, and hero science, to explain sex differences in cognitive aging and age-related neurodegenerative diseases, and to develop new therapeutic targets.”

Effect of acute intensity aerobic exercise on CTSB circulation. CTSB circulation before and 30 minutes after AE A) 40% VO2max, B) 65% VO2max, C) 80% VO2max, and D) at VO2max. n = 15 (9 months/6 women) 80% VO2max, n = 16 (10 months/6 women) all other time points. (Credit: Credit: Mamta Rai and Fabio Demontis, Brain Plasticity)

Crosstalk studies between the brain and adipose tissue, especially a hormone that can cross the BBB and has been shown to improve neuronal function in animal models of Alzheimer’s disease; accumulating evidence that neurogenesis can be regulated by the gut microbiome; studies on the effect of exercise and diet on BDNF signaling in the hippocampus are also reviewed, which offer approaches for the treatment of neurodegenerative conditions.

“The research compiled in this issue supports the importance of exercise for memory function,” said co-guest editor Christian D. Vrann, PhD, MD, Massachusetts General Hospital and Harvard Medical School. “We are excited to share this exciting special edition. Many more brain-related systemic molecules are likely to be discovered in the coming years, and they could provide the basis for new therapeutic approaches for neurodegenerative diseases.”

To learn more about scientific stories, check out our New Discoveries section at The bright side of the news.

Note: Materials courtesy of IOS Press above. Content can be edited for style and length.

Do you like such pleasant stories? Get Brighter Side of News Newsletter.