Brief Summary
A 2025 study identified two existing cancer drugs, letrozole and irinotecan, as promising candidates for reversing Alzheimer's brain damage. Researchers found that these drugs, when used in combination, reduced tau protein levels and improved learning and memory in mice. This approach targets multiple types of brain cells affected by Alzheimer's, offering a potential path to more personalized and effective treatments.
- Letrozole and irinotecan, already FDA-approved, could expedite clinical trials for Alzheimer's.
- The drugs reversed gene expression changes associated with Alzheimer's in the brain.
- Combination therapy reduced harmful tau protein clumps and improved cognitive functions in mice.
Scientists Identify Existing Drugs to Reverse Alzheimer's Brain Damage
In a 2025 study, scientists investigated existing drugs for treating Alzheimer's disease and identified letrozole and irinotecan, both used in cancer treatment, as promising candidates. These drugs are already approved by regulators in the US, potentially allowing for quicker initiation of clinical trials for Alzheimer's.
Research Methodology and Findings
The US research team began by examining how Alzheimer's alters gene expression in the brain. They then used the Connectivity Map, a medical database, to find drugs that could reverse these gene expression changes. They also cross-referenced records of cancer patients who had taken these drugs and found a decreased risk of developing Alzheimer's among them.
Impact of Letrozole and Irinotecan on Alzheimer's
The application of letrozole and irinotecan reduced the level of tau proteins in mouse brains. After identifying these drugs as top candidates, the researchers tested them on mouse models of Alzheimer's. The tandem use of letrozole and irinotecan reversed some brain changes caused by the disease, significantly reducing harmful tau protein clumps and improving learning and memory in the mice.
Targeting Brain Cells with Combined Therapy
By combining letrozole and irinotecan, the researchers were able to target different types of brain cells affected by Alzheimer's. Letrozole appeared to counteract Alzheimer's in neurons, while irinotecan had an effect on glia. This dual action is crucial because Alzheimer's results from numerous alterations in genes and proteins that disrupt brain health.
Future Steps and Implications
While the drugs have shown promise in mice, further research is necessary, including clinical trials for people with Alzheimer's disease. The researchers suggest that this approach could lead to more personalized and effective treatments based on individual gene expression changes. With over 55 million people affected by Alzheimer's and the number expected to double in the next 25 years, finding ways to prevent or reverse the disease is critical for global health.
