Innovative Use of Commercial Dyes Promises Advances in Dementia Diagnosis

Researchers at the University of California, San Francisco, are exploring the potential of repurposing industrial dyes to improve the diagnosis of dementia. Currently, diagnosing conditions like Alzheimer's and other dementias relies heavily on behavioral assessments, with brain scans and blood tests often providing inconclusive results during a patient's life. Definitive diagnoses are typically confirmed only post-mortem.

To bridge this diagnostic gap, scientists conducted a large-scale screening of hundreds of commercially available dyes to determine their affinity for protein aggregates characteristic of dementia-related brain changes. Specifically, they examined dyes' ability to bind to different forms of tau protein, which forms abnormal clumps in diseases such as Alzheimer’s, progressive supranuclear palsy, and frontotemporal dementia.

The team created various shapes of tau clumps in the lab and tested 300 dyes for their binding properties. Through repeated experiments, they narrowed down the list to 27 promising candidates, ultimately identifying 10 dyes that reliably attached to specific tau structures. One of these dyes successfully highlighted tau accumulations in an animal model of Alzheimer’s and in samples from deceased patients.

Besides tau, scientists also evaluated the dyes' ability to bind other disease-related protein clumps, with some promising hits discovered. This innovative screening approach showcases how existing chemical molecules can be repurposed, potentially leading to the development of new, highly specific diagnostic tools for different types of dementia.

Professor Jason Gestwicki emphasized that, despite the slow progress historically in diagnosing and treating dementias, their methodology offers a more efficient way to discover diagnostic dyes. The researchers hope this approach will accelerate the development of better diagnostic techniques, enabling earlier and more accurate detection of these neurodegenerative conditions.

The study was published in Nature Chemistry, and the findings open new avenues for utilizing industrial chemistry in biomedical applications, including neurology and beyond.