Study provides new insights into biological processes linked to Huntington’s disease

A study conducted by the Sant Pau Research Institute (IR Sant Pau) and Hospital de Sant Pau has identified for the first time in living individuals a brain pattern related to the tau protein that changes according to the stage of Huntington's disease. This discovery opens the door both to the use of new biomarkers for monitoring the disease and to the development of treatments for a condition for which no therapeutic options are currently available.

Using positron emission tomography-a molecular neuroimaging technique known as PET-and the second-generation radiotracer [¹8F]PI-2620, the researchers demonstrated that this signal can already be detected in some mutation carriers who have not yet developed clinically manifest disease and that, as the disease progresses, the signal increases and spreads according to an organized anatomical distribution.

The study, published in the European Journal of Nuclear Medicine and Molecular Imaging, provides new insights into the biological processes that occur between the genetic alteration responsible for the disease and the onset of its motor, cognitive, and neuropsychiatric manifestations. The findings suggest that tau-related alterations may form part of a cascade of secondary mechanisms capable of amplifying, modifying, or influencing disease progression.

"We have known for some time that tau may play a role in Huntington's disease, but we had never been able to study in the brains of living individuals how this signal was distributed or how it varied across the different stages of the disease," explains Dr. Saül Martínez-Horta, a neuropsychologist in the Movement Disorders Unit of the Neurology Department at Hospital de Sant Pau, a researcher at IR Sant Pau, and first author of the study. "Our findings show that a tau-related biological process is already present before manifest disease develops and that it follows a clearly defined anatomical organization, particularly in certain subcortical regions," he adds.