Test may predict Alzheimer’s 3.5 years before diagnosis

By Elissa Wolfson, The Science Advisory Board assistant editor

January 30, 2023 -- King's College London researchers have developed a blood-based test that could be used to predict the risk of Alzheimer's disease up to 3.5 years before clinical diagnosis. The study, published January 27 in the journal Brain, indicates that human blood components can affect the formation of new brain cells, a process called neurogenesis.

Neurogenesis occurs in a part of the brain involved in learning and memory, called the hippocampus. While Alzheimer's disease affects the formation of new brain cells in the hippocampus during the early stages of the disease, previous studies have only been able to study neurogenesis in its later stages, through autopsies.

To better understand the early changes, researchers collected blood samples over several years from 56 individuals with mild cognitive impairment. While not everyone experiencing this condition went on to develop Alzheimer's disease, those who did progressed to a diagnosis at a much higher rate than others. Of the 56 participants in the study, 36 later received an Alzheimer's diagnosis.

The researchers treated brain cells with blood taken from people with mild cognitive impairment, exploring how those brain cells changed in response to blood exposure as Alzheimer's disease progressed.

The blood samples collected from participants who subsequently developed Alzheimer's disease promoted a decrease in cell growth and division and an increase in apoptotic cell death -- the process by which cells are programmed to die. However, these blood samples also increased the conversion of immature brain cells to hippocampal neurons. While reasons for this increased neurogenesis remain unclear, the researchers hypothesize that it may be an early compensating mechanism for the neurodegeneration (loss of brain cells) experienced by those developing Alzheimer's disease.

Previous studies showed that blood from young mice could have a rejuvenating effect on the cognition of older mice by improving hippocampal neurogenesis.

The researchers sought to model the neurogenesis process in a lab using human brain cells and human blood, in order to better understand neurogenesis and the prediction of Alzheimer's disease. They found the first evidence in humans that the body's circulatory system can affect the brain's ability to form new cells. When the researchers used blood samples collected long before the participants' Alzheimer's disease diagnosis, they found that the neurogenesis changes occurred 3.5 years prior to clinical diagnosis.

The findings potentially allow noninvasive early prediction of Alzheimer's onset, according to the researchers. This could complement other blood-based biomarkers that reflect classical signs of the disease, such as the accumulation of Alzheimer's flagship proteins amyloid and tau.

The researchers said that their work may also help illuminate changes the brain undergoes at the earliest Alzheimer's disease stages, potentially leading to earlier detection and interventions such as identifying individuals with memory problems who might benefit from clinical trials of disease-modifying Alzheimer's drugs.

"It is now essential to validate these findings in a bigger and more diverse group of people," said co-first author Dr. Hyunah Lee in a statement.

Increasing immune cell production may reverse cognitive decline: study
Rutgers University researchers have discovered that the underproduction of immune cells called mucosal-associated invariant T cells contribute to Alzheimer’s...
Gene mutation may explain Alzheimer's brain plaque buildup
Researchers at the New York University Grossman School of Medicine and the Icahn School of Medicine at Mount Sinai have found that a gene mutation may...
Alzheimer's risk gene degrades brain's 'wiring'
Massachusetts Institute of Technology-based researchers investigated the gene variant APOE4, which increases the risk of Alzheimer's disease, revealing...
Stimulating immune cells around the brain could be Alzheimer's treatment
An immune-stimulating compound rejuvenates immune cells and improves waste clearance from the brain, which could help treat people with Alzheimer's, Parkinson's,...
Nucleolin could be key to understanding neurodegenerative disorders
A new study challenges recent theories of the role structures inside the nucleus play in neurodegenerative disorders and suggests the relevance of researching...
NIH grant to fund early Alzheimer's detection
A $1.2 million National Institutes of Health (NIH) grant will help Penn State-led researchers explore the development of a machine-learning system to...
Gene overexpression may protect against Alzheimer’s disease: study
Scientists at the University of Colorado Anschutz Medical Campus have discovered the overexpression of a gene tied to cell division and the structure...
CRISPR interference screening reveals mitochondrial door linked to Alzheimer's, cancer
Using CRISPR interference screening, scientists at the Whitehead Institute have uncovered the gene that serves as a doorway to the mitochondrial membrane,...
Brain molecule discovery may help treat Alzheimer's, MS
University of Virginia researchers have discovered a molecule in the brain responsible for coordinating the brain's cleansing of detritus associated with...
RNA splicing defects in mouse model sheds light on Alzheimer’s
St. Jude Children’s Research Hospital scientists created a mouse model to study the role of RNA splicing defects in Alzheimer’s disease, revealing degeneration...
Brain tissue mechanism may explain why women are more susceptible to Alzheimer's
Case Western Reserve University researchers have identified a mechanism in brain tissue that may explain why women are twice as vulnerable to Alzheimer’s...
Link between ion channel and cholesterol in brain may lead to novel treatments for Alzheimer’s
Mechanical forces and tissue functions influence the morphology of the developing brain, according to University of California, Irvine researchers, who...
Boosting neuron production offers viable treatment strategy for Alzheimer’s: mice study
A new study from University of Illinois Chicago researchers shows that boosting neurogenesis, the process by which new neurons are formed in the brain,...

Copyright © 2023 scienceboard.net

Science Advisory Board on LinkedIn
Science Advisory Board on Facebook
Science Advisory Board on Twitter