Memory and brain condition may depend on an enzyme produced during exercise. Research has revealed a new pathway for the influence of physical activity.
Brain / © Pixabay
Physical activity might safeguard the brain not only through its effects on neurons but also by restoring blood vessels. Researchers have discovered that a liver enzyme released during exercise strengthens the brain’s barrier and improves memory in mice.
This was reported by the publication Earth.com.
The enzyme in question is GPLD1, which enters the bloodstream after physical exertion. Work by a team at the University of California, San Francisco, led by Saul Villeda, demonstrates that this enzyme does not directly penetrate the brain but acts on the surface of the blood vessels surrounding the brain.
A key factor in brain aging has been found to be the deterioration of the blood-brain barrier – the structure separating blood flow from brain tissue. In older mice, this barrier becomes more permeable, leading to “leaks” in the vessels through which small molecules can enter the brain. This, in turn, triggers stress signals in cells and is associated with memory impairment.
Previous studies have indicated that the barrier’s permeability increases with age and correlates with poorer cognitive performance. Similar dysfunctions have also been observed in the early stages of Alzheimer’s disease.
In aging mice, an age-related protein accumulation on the surface of vascular cells weakens the protective barrier. The GPLD1 enzyme selectively removes this specific accumulation, with minimal impact on other surface proteins.
Experiments have shown that when young mice had their amount of such accumulation artificially increased, they began to perform worse on memory tasks and behaved similarly to older animals. This allowed for testing whether the removal of this accumulation affects brain functions.
When older mice were administered additional GPLD1, the enzyme reached the brain’s blood vessels via the bloodstream and reduced these age-related accumulations on their surface. Consequently, the barrier became less permeable, inflammation decreased, and the animals demonstrated better results in memory tests. Some of the age-related changes in vascular cells also shifted towards a more “youthful” state.
The researchers also examined an alternative approach – a compound added to food that reduced these accumulations without penetrating the brain. The effect was similar: the vessel walls strengthened, and cognitive performance improved.
In mice genetically modified to form plaques characteristic of Alzheimer’s disease, an increased level of the GPLD1 enzyme contributed to a reduction in these deposits in the hippocampus – the brain region responsible for memory. A similar effect was observed when blocking accumulations in the blood vessels, which also reduced the overall plaque burden in the brain. Concurrently, analysis of brain samples from elderly individuals with Alzheimer’s disease revealed an elevated level of the same vascular accumulations.
“These findings suggest healthier blood vessels as one way to reduce neuronal burden, though only clinical trials can determine if this strategy works in humans,” the article states.
Scientists note that the results are currently derived from animal studies, and clinical trials are needed to confirm efficacy in humans. Furthermore, GPLD1 is involved in various bodily processes, so potential therapeutic interventions must be thoroughly investigated.
Recall that scientists previously discovered that industrial food processing “switches off” attention and alters human cognitive abilities.
Comments Sort: New Old Popular Submit
Source: tsn.ua