Exercise

Exercise brings changes to the brain that are beneficial for MS

 

What is happening in MS?

Multiple sclerosis (MS) is a chronic disease with damage to the central nervous system (the brain and the spinal cord). In our central nervous system, nerve cells (neurons) communicate with each other by sending signals along a long cellular projection called an axon. Axons have an insulating layer that wraps around them like a sheath. This layer, called the myelin sheath, functions like the outer rubber layer that insulates electrical wires to ensure signals are transmitted quickly and effectively between neurons. Neurons do not make their own myelin sheath. Instead, the sheath is made by one type of support cell for neurons called oligodendrocytes.

In MS, the immune system that protects us from pathogens and infections becomes aberrant. It starts to attack the protective myelin layer and causes damage to the myelin sheath (we call this process demyelination) and axons. This damage compromises and disrupts signal transmission between neurons, manifesting in patients as various symptoms. Some of the damage to the myelin sheath can be repaired by the inherent repair mechanism in our body (we call this progress remyelination). However, prolonged, and extensive damage to the myelin sheath can put tremendous stress and harm on axons, resulting in the loss of axons and subsequent loss of neurons (we call this neurodegeneration).  The continuous loss of axons and neurons is believed to be the principal contributor to increasing disease severity and progression of disability in MS.

 

Why exercise is good for MS?

Historically, people with MS were advised to avoid physical activity to reduce symptoms. Exercise can also be challenging and intimidating, especially if people with MS suffer from heat sensitivity, fatigue, and decreased mobility. However, emerging research suggests that exercise not only improves the health and well-being of MS patients but also has therapeutic benefits (a thorough review on the topic can be found in those publications)1–6.

 

Research indicates that exercise brings beneficial functional and structural changes to the brain. Remember the support cells, oligodendrocytes, that make the myelin sheath? They have amazing abilities to repair and rewrap myelin around axons that have damaged or lost myelin sheath. However, these support cells are also under attack by the dysfunctional immune system in MS. In addition, there is only a limited time window when these support cells can make myelin. To help repair myelin and protect neurons, the brain needs to produce more of those support cells, and they need to get to the right place to do the right repair job. Research shows that exercise can increase the number of oligodendrocytes and help the repair process after injury. One research that specifically investigates the myelin repair in an animal model has an interesting finding: remyelination achieved by exercise was comparable to that achieved by a remyelination-stimulating medication. More importantly, there is a synergistic response in remyelination when exercise and the medication are used together7.

 

Exercise can also be neuroprotective. This effect can manifest in multiple ways, including increasing the production and release of beneficial molecules in the brain, increasing neural activity, and reducing brain volume loss. The beneficial molecules (they are called neurotrophic factors) are growth factors that promote proliferation, differentiation, growth and survival of neurons and support cells. One example of neurotrophic factors is a molecule called brain-derived neurotrophic factor (BDNF). BDNF is critical to myelin repair and human studies have shown that exercise increases BDNF levels in the serum of MS patients. However, not all exercise is equivalent in regulating neurotrophic factors. Exercise intensity, training regimen, and body weight may affect changes in those factors. The type of MS that patients have may also influence the changes.

 

In addition to the beneficial effects on the brain, exercise also modulates the immune system. In MS, aberrant immune cells travel to the central nervous system and cause inflammation there (we call this neuroinflammation). Neuroinflammation is a significant contributor to the loss of axons and neurons.  Research showed that exercise can strengthen the barrier that guards the travelling of dysfunctional immune cells to the brain8. In addition, exercise seems to create a more anti-inflammatory environment in the central nervous system that helps suppress abnormal inflammation7,9,10.

 

Summary

Emerging research has provided evidence to support the benefits of exercise in MS. However, much remains to be known on the underlying mechanism. Further exploration of the relationship between exercise and beneficial central nervous system outcomes would provide insights and guidance on the design of the best approaches for prevention, mitigation and therapeutic intervention.

 

About AnthoBio:

AnthoBio Inc is a Canadian biomedical research company dedicated to providing safe and natural therapeutic options for individuals living with multiple sclerosis. The AnthoBio team takes pride in their evidence-based approach in developing a natural product that is safe, accessible, and affordable to individuals to help them live better with their MS.

 

References:

  1. Guo LY, Lozinski B, Yong VW. Exercise in multiple sclerosis and its models: Focus on the central nervous system outcomes. J Neurosci Res. 2020 Mar 1;98(3):509–23.
  2. Lozinski BM, Yong VW. Exercise and the brain in multiple sclerosis. Mult Scler J. 2020;1352458520969099.
  3. Doulatabad SN, Nooreyan K, Doulatabad AN, Noubandegani ZM. The Effects of Pranayama, Hatha and Raja Yoga on Physical Pain and the Quality of Life of Women with Multiple Sclerosis. Afr J Tradit Complement Altern Med. 2012 Oct 1;10(1):49–52.
  4. Guner S, Inanici F. Yoga therapy and ambulatory multiple sclerosis Assessment of gait analysis parameters, fatigue and balance. J Bodyw Mov Ther. 2015 Jan 1;19(1):72–81.
  5. Salgado BC, Jones M, Ilgun S, McCord G, Loper-Powers M, van Houten P. Effects of a 4-month Ananda Yoga Program on Physical and Mental Health Outcomes for Persons With Multiple Sclerosis. Int J Yoga Ther. 2013 Oct 28;23(2):27–38.
  6. Sandroff BM, Hillman CH, Benedict RHB, Motl RW. Acute effects of walking, cycling, and yoga exercise on cognition in persons with relapsing-remitting multiple sclerosis without impaired cognitive processing speed. J Clin Exp Neuropsychol. 2015 Feb 7;37(2):209–19.
  7. Jensen SK, Michaels NJ, Ilyntskyy S, Keough MB, Kovalchuk O, Yong VW. Multimodal Enhancement of Remyelination by Exercise with a Pivotal Role for Oligodendroglial PGC1α. Cell Rep. 2018 Sep 18;24(12):3167–79.
  8. Souza PS, Gonçalves ED, Pedroso GS, Farias HR, Junqueira SC, Marcon R, et al. Physical Exercise Attenuates Experimental Autoimmune Encephalomyelitis by Inhibiting Peripheral Immune Response and Blood-Brain Barrier Disruption. Mol Neurobiol. 2017 Aug;54(6):4723–37.
  9. Kohman RA, Bhattacharya TK, Wojcik E, Rhodes JS. Exercise reduces activation of microglia isolated from hippocampus and brain of aged mice. J Neuroinflammation. 2013 Sep 18;10(1):885.
  10. Mandolesi G, Bullitta S, Fresegna D, De Vito F, Rizzo FR, Musella A, et al. Voluntary running wheel attenuates motor deterioration and brain damage in cuprizone-induced demyelination. Neurobiol Dis. 2019 Sep 1;129:102–17.

 

%d bloggers like this: