A good blood supply is good for memory
February 14, 2020
Science Daily/DZNE - German Center for Neurodegenerative Diseases
Memory performance and other cognitive abilities benefit from a good blood supply to the brain. This applies in particular to people affected by a condition known as "sporadic cerebral small vessel disease." Researchers of the German Center for Neurodegenerative Diseases (DZNE) and the University Medicine Magdeburg report on this in the journal "BRAIN." Their study suggests that blood perfusion of the so-called hippocampus could play a key role in age- and disease-related memory problems.
Inside the human brain there is a small structure, just a few cubic centimeters in size, which is called the "hippocampus" because its shape resembles a seahorse. Strictly speaking, the hippocampus exists twice: once in each brain hemisphere. It is considered the control center of memory. Damage to the hippocampus, such as it occurs in Alzheimer's and other brain diseases, is known to impair memory. But what role does blood supply in particular play? A team of scientists headed by Prof. Stefanie Schreiber and Prof. Emrah Duezel, both affiliated to the DZNE and the University Medicine Magdeburg, investigated this question. The researchers used high-resolution magnetic resonance imaging (MRI) to examine the blood supply to the hippocampus of 47 women and men aged 45 to 89 years. The study participants also underwent a neuropsychological test battery, which assessed, in particular, memory performance, speech comprehension and the abilty to concentrate.
A double supply line
"It has been known for some time that the hippocampus is supplied by either one or two arteries. It also happens that only one of the two hippocampi, which occur in every brain, is supplied by two vessels. This varies between individuals. The reasons are unknown," explained Schreiber. "Maybe there is a genetic predisposition. However, it is also possible that the individual structure of the blood supply develops due to life circumstances. Then the personal lifestyle would influence the blood supply to the hippocampus." In the cognition tests, those study participants in whom at least one hippocampus was doubly supplied generally scored better. "The fact that the blood supply is fundamentally important for the brain is certainly trivial and has been extensively documented. We were therefore particularly focused on the hippocampus and the situation of a disease of the brain vessels. Little is actually known about this."
Patients benefited in particular
Of the study subjects, 27 did not manifest signs of brain diseases. The remaining twenty participants showed pathological alterations in brain blood vessels, which were associated with microbleeding. "In these individuals, sporadic cerebral small vessel disease had been diagnosed prior to our investigations," said Dr. Valentina Perosa, lead author of the current study, who is currently doing postdoctoral research in Boston, USA. These individuals exhibited a broad spectrum of neurological anomalies, including mild cognitive impairment. "The healthy subjects generally scored better on cognitive tests than the study participants with small vessel disease. Among the participants with disease, those with at least one hippocampus supplied by two arteries reached better scores in cognition. They particularly benefited from the double supply. This may be due to a better supply not only of blood but also of oxygen. However, this is just a guess," said Perosa.
Starting point for therapies?
"Our study shows a clear link between blood supply to the hippocampus and cognitive performance," Schreiber summarised the results. "This suggests that brain blood flow might play a key role in the declining of memory performance, whether caused by age or disease." Such findings help to understand disease mechanisms and can also be useful for the development of novel treatment options, she indicates: "At present we can only speculate, because we don't know, but it is possible that lifestyle has an influence on the formation of the blood vessels that supply the hippocampus. This would then be a factor that can be influenced and thus a potential approach for therapies and also for prevention. This is a topic we intend to investigate."
https://www.sciencedaily.com/releases/2020/02/200214134725.htm
Study of 'SuperAgers' offers genetic clues to performance
MAP2K3 genetic variants could help slow age-related memory loss
May 30, 2018
Science Daily/The Translational Genomics Research Institute
Recent studies have shown that SuperAgers have less evidence of brain atrophy, have thicker parts of the brain related to memory, and lower prevalence of the pathological changes associated with Alzheimer's disease. Now, a study suggests that having resilient memory performance during aging could be inherited, and that a particular gene might be associated with SuperAgers.
All humans experience some cognitive decline as they age. But how is it that some people in their 80s and beyond still have memory capacity of those 30 or more years younger?
Recent studies have shown that these SuperAgers have less evidence of brain atrophy, have thicker parts of the brain related to memory, and lower prevalence of the pathological changes associated with Alzheimer's disease.
Now, a study by the Translational Genomics Research Institute (TGen), an affiliate of City of Hope, and Northwestern University Feinberg School of Medicine suggests that having resilient memory performance during aging could be inherited, and that a particular gene might be associated with SuperAgers.
The study results, published today in the journal Frontiers in Aging Neuroscience, suggest that therapies targeting the MAP2K3 gene could reduce age-related memory decline, and perhaps the threat of memory loss posed by Alzheimer's disease.
"This study suggests that SuperAgers may have a genetic 'leg up' on the normal aging population -- they may have higher resistance to age-related cognitive changes -- and also that this might highlight a new way to enhance memory performance," said Dr. Matt Huentelman, Ph.D., TGen Professor of Neurogenomics, and the study's lead author.
Researchers sequenced the genomes of 56 SuperAgers in the hunt for genetic variations. They defined SuperAgers as those individuals 80 years or older who scored at or above average normative values for adults age 50-65 in episodic memory tests, and at least average-for-age in other cognitive tests.
They compared these to a control group of 22 cognitively average individuals, those who scored within the average-for-age on episodic memory and other cognitive tests, as well as with a large group of individuals from the general population.
They found that the SuperAgers were enriched for genetic changes in the MAP2K3 gene compared to the two control groups.
"Based on our findings, we postulate MAP2K3 inhibitors may represent a novel therapeutic strategy for enhanced cognition and resistance to Alzheimer's disease," said Dr. Emily J. Rogalski, Ph.D., Associate Professor at the Mesulam Cognitive Neurology and Alzheimer's Disease Center at Northwestern's Feinberg School of Medicine, and the study's senior author. "Replication of the finding and mechanistic studies are important next steps."
https://www.sciencedaily.com/releases/2018/05/180530113217.htm