The Road to a Cure for Alzheimer's

Stanford Medicine’s “Rethinking Alzheimer’s” series highlights a shift away from viewing Alzheimer’s solely through the lens of amyloid plaque buildup and toward a more comprehensive understanding rooted in genetics, immunity, and metabolism. For decades, scientists focused on A-beta plaques that gather between neurons, assuming they were responsible for memory loss, yet clearing these plaques did little to help patients. This failure pushed researchers to explore deeper causes, including the APOE gene, especially the APOE4 variant carried by about one-fifth of the population and strongly linked to early-onset Alzheimer’s. APOE’s role in transporting fats throughout the brain and body has become central to rethinking how the disease develops and why APOE4 may increase risk more than the other three known versions of the gene.
The series also explains why “plaque-attack” treatments fall short by shifting attention to neurofibrillary tangles, which form inside neurons and strongly contribute to their degeneration. These tangles are made from tau, a protein normally responsible for stabilizing the cell’s internal structure, but chemical changes can cause it to clump into harmful aggregates. A key finding is that individuals carrying the HLA-DR4 variant may naturally block tau clumping because DR4 binds to specific modified regions of tau, opening the door to immune-based therapies that mimic this protective effect. At the same time, aging-related inflammation emerges as another driving factor. Macrophages in the body become more reactive with age, producing chronic inflammation that, according to Stanford neuroscientist Kati Andreasson, “fuels brain aging in general and Alzheimer’s in particular.” Her team found that high levels of the inflammatory molecule TREM1 increase Alzheimer’s risk, and in mice, removing TREM1 from macrophages protected cognition without reducing amyloid plaques, meaning changes in the body’s immune system can influence the brain.

The final article expands this immune-metabolic view by identifying a third major hallmark of Alzheimer’s: the accumulation of lipid droplets, or tiny balls of fat, inside microglia, the brain’s resident immune cells. These droplets were largely overlooked in older autopsy samples because standard preparation methods washed away most lipids. Microglia, which make up roughly 15% of brain cells, normally clear pathogens and support neuron health, but with age, and especially in individuals carrying APOE4, they begin to store excess fat and become more inflammatory. Stanford researchers found that microglia overloaded with lipid droplets were linked to more severe amyloid and tau pathology and worse cognitive outcomes, suggesting this fat buildup plays an active role in neuro degeneration. Together, these findings connect genetic risk (APOE4), tau toxicity, and immune dysfunction with altered lipid metabolism, offering a more integrated, and promising, direction for future Alzheimer’s treatments.

Linked below is a pdf of a more extensive analysis of the four articles included in the studies, it was much too long for a blog post but I found a lot of information through these articles.

The Road to a Cure for Alzheimer's pdf

Sources: 

Goldman, Bruce. “Rethinking Alzheimer’s: Why This Common Gene Variant Is Bad for Your Brain.” News Center, 25 Sept. 2025, med.stanford.edu/news/insights/2025/09/rethinking-alzheimers-gene-variant-apoe4.html. 

Goldman, Bruce. “Rethinking Alzheimer’s: Untangling the Sticky Truth about Tau.” News Center, 23 Sept. 2025, med.stanford.edu/news/insights/2025/09/rethinking-alzheimers-tau-protein.html.

Goldman, Bruce. “Rethinking Alzheimer’s: Could It Begin Outside the Brain?” News Center, 24 Sept. 2025, med.stanford.edu/news/insights/2025/09/rethinking-alzheimers-outside-brain-macrophages.html.

Goldman, Bruce. “Rethinking Alzheimer’s: How These Tiny Balls of Fat Factor In.” News Center, 25 Sept. 2025, med.stanford.edu/news/insights/2025/09/rethinking-alzheimers-tiny-balls-fat-microglia.html.

A Decreased Risk of Alzheimer's and Parkinson's in Your Genes?

Alzheimer's, Parkinson's, and The DR4 Gene

    A recent Stanford led medical study about Parkinson's disease (PD) and Alzheimer's disease has revealed that people with a mutation of the DR4 gene have a decreased risk of PD and Alzheimer's. About 1 in 5 people carry the mutation of the DR4 gene, which was discovered to reduce the chance of developing PD or Alzheimer's by 10%. Researchers also believe the tau proteins involved in Alzheimer's may also be involved with PD, hence the close relatedness of decreased risks that we see in this article and the gathered genomic-based conclusions. Other studies have shown that the DR4 mutation protects against PD, and combining the new research, it is believed that it may pose the same effect in preventing Alzheimer's. The data suggested that in people with DR4, there were fewer neurofibrillary tangles, which as associated with the tau proteins that aggressively effect the brains of those with Alzheimer's disease as it progresses, creating the plaque that impairs cognition.  There are immunological connections with DR4 as well, and they are promising enough to possibly initiate the creation of a vaccine that can attack and destroy the fibers that create the tau proteins coating the brain.

    With a significant increase in patients with both PD and Alzheimer's, this idea of a vaccine could be very promising and useful in the near future. Also, the fact that the scientists at Stanford were able to discover and pinpoint the exact gene is also very exciting as well. As we continue to make these advances in science and medicine, many things are looking up in our future and the future of middle aged individuals that will soon be susceptible to deteriorating and life altering diseases and conditions. Overall, this article was exciting to read because of how relevant this is to the conditions we are facing in the medical field, and have been, over the past two decades. With this in mind, what these scientists and Stanford University are doing is amazing, and I am ecstatic to be in the field of biology at this time in our world!

LINKS:

1) https://med.stanford.edu/news/all-news/2023/08/stanford-medicine-led-study-finds-genetic-factor-fends-off-alzhe.html 

2) https://www.sciencealert.com/a-single-gene-variant-protects-from-both-alzheimers-and-parkinsons 

Tau protein- not amyloid may be a key driver of Alzheimer's symptoms

The sticky-plaques of beta-amyloid protein is one of the most well known signs of Alzheimer’s disease (AD). These plaques are known to gather around neurons which blocks information processing and kills cells. There is a second protein, called tau, that scientists are now suggesting may be the real reason for dementia and memory loss in AD patients. By using positron emission tomography (PET), the beta-amyloid protein deposits can be visualized in people with AD along with postmortem brain tissue analyses, and brains of healthy people. It was shown that beta-amyloid protein plaques can be found in abundance even in the brains of healthy people without Alzheimer’s, specifically about 30% of healthy people have brains full of beta-amyloid protein. With further testing and PET imaging, it was shown that more tau deposits found in the temporal lobe, the more likely a person was to show deficits when performing memory and attention tests. While no associations have been proven between tau and memory loss, it is interesting to see the further advancements toward the discovery of how this disease works differently in each person’s brain.

Tau Protein
Alzheimer's Disease