Spanish researchers have found that during long marathon distances, in conditions of critical energy deficit, the brain begins to use myelin, which covers neuronal processes and is involved in accelerating signal transmission.
Marathon races in themselves seriously exhaust the body, posing a threat to the kidneys, stomach, causing a risk of cardiovascular failure and injury of the musculoskeletal system. In a new study, researchers from the San Sebastian CIC biomaGUNE analyzed the effect of a long run on the brain. In particular, they observed a decrease in the key biomarker myelin. This is the adipose tissue that covers neuronal processes. Under severe stress, the brain begins to use myelin as a source of energy.
However, the researchers add that such effects reversible as soon as the brain is running out supply of its standard energy source – glucose or sugar – it turns to backup generators, metabolizing fats as an alternative fuel source.
In general, the brain consumes up to 20% of all the energy produced by our body. If the usual sources of energy are exhausted the brain begins to suffer.
According to researcher Pedro Ramos Cabrera, he and other scientists sought to identify backup sources of brain power. They guessed that one of these sources could be myelin Previous studies in rodents have suggested that fatty acids derived from the breakdown of myelin may help increase brain cell survival.
The researchers used MRI to scan the brains of 10 runners 48 hours before they completed the marathon. After that, the scan was repeated 2 days later and again — 2 months later. MRI helped researchers detect the presence of water molecules trapped between layers myelin.
According to the scan results, it was found that 2 days after the race, the level of myelin in certain areas of the white matter decreased by about 10-28%, which cannot cause irreversible consequences.
«The areas in which we observed more significant changes were related to motor circuits and the emotional control center of the brain,including the corticospinal pathway, cerebellar pons, and radial corona», — Pedro Ramos Cabrera clarifies.
However, within 2 months, the myelin level in runners returned to normal The authors call this phenomenon metabolic myelin plasticity. They suggest that in conditions of glucose deficiency, the brain can temporarily use lipids from myelin as a source of energy. This does not destroy the entire insulating layer, but affects only a part of the fibers and is gradually restored.
However, these effects may carry an increased risk for some athletes. For example, in people with amyotrophic lateral sclerosis, the metabolic molecules that normally produce myelin are in short supply, and researchers believe that excessive exercise can potentially worsen the problem.
At what age does the brain start to age and how to prevent it, — research