A new drug originally developed to treat a different brain disease is now showing signs that it could help people with Alzheimer’s disease too. The drug, called NU-9, is a small molecule that has already been approved by the U.S. Food and Drug Administration (FDA) for clinical trials for treating ALS (amyotrophic lateral sclerosis).
In a recent study by Northwestern University, researchers found that NU-9 also improves the health of brain cells in mice with Alzheimer’s disease.
Alzheimer’s and ALS are different diseases, but they share something in common: both involve a buildup of misfolded proteins in the brain. These proteins are normally helpful, but when they clump together in the wrong way, they become harmful. In ALS, a protein called SOD1 misfolds and causes damage.
In Alzheimer’s, the problem is caused by clumps of amyloid beta proteins. These sticky proteins gather in and around brain cells, disrupting their normal work, harming connections between cells, and eventually causing the brain cells to die. This leads to memory loss, confusion, and other symptoms of Alzheimer’s.
The study showed that NU-9 doesn’t just treat symptoms—it works on the root cause. It helps brain cells get rid of these harmful protein clumps. NU-9 was first shown to improve neuron health in animal models of ALS by doing exactly that. Scientists then wondered if it could work the same way for Alzheimer’s.
To find out, the researchers first ran experiments using cultured brain cells from animals. In one test, they added amyloid beta proteins to the brain cells and saw that the proteins quickly clumped up and stuck to the cells. In a second test, they gave the cells NU-9 before adding the proteins.
The cells treated with NU-9 had much fewer protein clumps, both inside the cells and along the parts of the cells that help them send messages (called dendrites). Even after the drug was removed, the protective effect remained—suggesting that NU-9 might have lasting benefits.
Next, they tested NU-9 on mice bred to show symptoms of Alzheimer’s. The mice were given the drug by mouth. After the treatment, the mice performed better on memory tests. These are the kinds of tests researchers use to measure thinking and learning in animal models.
Even more exciting, the brains of these mice showed less inflammation—a common and damaging feature of Alzheimer’s disease. NU-9 not only stopped the buildup of harmful protein clumps, but also reduced the brain’s immune response, which can cause more damage if left unchecked.
So how does this drug actually work? The scientists discovered that NU-9 uses the cell’s own recycling system to get rid of the protein clumps. Every cell has compartments that work like trash bins. One of these is called the lysosome.
It helps break down and clear out waste, including harmful proteins. NU-9 seems to help move amyloid beta proteins into these lysosomes, where they can be destroyed. A specific enzyme inside the lysosome, called cathepsin B, helps with this process.
Interestingly, the researchers also tested another type of trash bin in the cell, called the proteasome, but found it wasn’t involved. The lysosome appears to be the key player in how NU-9 works.
Still, they don’t know exactly how the drug activates this process. It’s possible that NU-9 helps hand off the harmful proteins from one part of the cell to another in a kind of relay race, ending in the lysosome. But the exact target of the drug remains unknown.
Though the findings are promising, more work is needed. The scientists want to test NU-9 more thoroughly in animals before trying it in humans with Alzheimer’s. They are also working on improving the drug to make it even more effective. In the future, they plan to see if NU-9 can help with other brain diseases like Parkinson’s or Huntington’s, which also involve toxic protein buildup.
One of the most exciting parts of this discovery is that NU-9 seems to treat a shared cause behind several neurodegenerative diseases, not just one.
This could mean that diseases once thought to be completely separate may actually be linked by common processes in the brain. If NU-9 or similar drugs can target that common cause, they might help treat multiple diseases before too much damage is done.
In summary, the study shows that NU-9 has real potential as a treatment for Alzheimer’s disease. It helps clear out toxic proteins from brain cells, reduces inflammation, and improves memory in animals. While it’s still early, these findings give researchers and families affected by Alzheimer’s a new reason to be hopeful.
If you care about Alzheimer’s disease, please read studies about the protective power of dietary antioxidants against Alzheimer’s, and eating habits linked to higher Alzheimer’s risk.
For more health information, please see recent studies that oral cannabis extract may help reduce Alzheimer’s symptoms, and Vitamin E may help prevent Parkinson’s disease.
The research findings can be found in PNAS.
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