Alzheimer’s disease (AD) is a progressive brain disorder that gradually robs people of their memory and thinking abilities. For many families, the diagnosis comes too late, leaving few options for effective intervention.
Researchers are exploring various methods to diagnose Alzheimer’s early, including artificial intelligence (AI) and many other techniques, but this approach holds enormous promise. A study published in Molecular Neurodegeneration offers hope by identifying specific biomarkers in blood that could act as early warning signs, shedding light on a new path for diagnosing and understanding Alzheimer’s disease.
Led by Xuemei Zeng and her colleagues, the study focused on using a cutting-edge proteomic technique called the NULISAseq CNS disease panel. This method allows researchers to measure a wide range of protein markers related to Alzheimer’s and other brain disorders directly from blood samples. What’s revolutionary here is the ability to monitor not just the classic hallmarks of Alzheimer’s, such as tau protein and amyloid beta, but also markers of inflammation, blood vessel health, and synaptic function, which are elements crucial in the early stages of the disease.
As Dr. Thomas Karikari, a key contributor to the study, puts it, “By capturing a comprehensive view of Alzheimer’s-related changes in the blood, we’re making strides toward earlier detection and a better understanding of the disease’s progression.”
The study examined blood samples from 113 older adults, most of whom were cognitively normal and living in economically disadvantaged regions of Pennsylvania. Using the NULISAseq panel, the researchers measured over 100 proteins. The results were promising: many of the protein markers showed strong correlations with the presence of amyloid plaques and tau tangles in the brain, even when participants had no obvious memory problems.
For instance, the performance of a protein known as p-tau217 stood out. This protein showed a strong ability to distinguish between those who had amyloid plaques in their brains and those who didn’t, even before symptoms appeared. Dr. Karikari explains, “p-tau217 in blood could serve as a critical biomarker for identifying individuals at risk of developing Alzheimer’s.” The study found that individuals with higher levels of p-tau217 were significantly more likely to have early-stage brain changes typical of Alzheimer’s.
Inflammation and Vascular Health
Alzheimer’s isn’t just about amyloid and tau; it involves a complex interplay of other processes like inflammation and changes in blood flow to the brain. This study is among the first to identify new blood-based markers of neuroinflammation and vascular health, such as TIMP3 and VEGFA. They found that these proteins undergo changes over time, potentially signaling the early stages of brain damage. For instance, TIMP3 levels were lower in individuals with early amyloid buildup, suggesting that these markers might provide new insights into how Alzheimer’s begins.
According to Zeng, “The ability to track these additional markers gives us a fuller picture of what is happening in the brain, helping us to understand not only who might develop Alzheimer’s but also how and why the disease progresses.”
Why It Matters
One of the biggest challenges in Alzheimer’s research is finding ways to detect the disease before it becomes symptomatic. Current methods like PET scans are expensive and not always accessible. Blood tests, on the other hand, could be a game-changer, offering a less invasive, more affordable, and widely available option for early diagnosis. This would allow doctors to intervene sooner, potentially slowing or even preventing cognitive decline.
Moreover, understanding the role of inflammation and blood vessel health in Alzheimer’s could open up new avenues for treatment. If researchers can pinpoint the early inflammatory responses that contribute to the disease, it might be possible to develop therapies that target these processes directly.
Although this study establishes a strong basis, further efforts are necessary to integrate blood tests for Alzheimer’s biomarkers into standard medical care. We need to confirm the findings in larger and more diverse populations to ensure their broad application, not just to specific groups. As they point out, most of their participants were non-Hispanic white adults, which limits the generalizability of the results.
For more, visit: https://doi.org/10.1186/s13024-024-00753-5
