Alzheimer's Disease: finding early indications of the disease for better therapeutic interventions

With the world's population ageing, the most common form of dementia, Alzheimer's disease (AD), has become a major public health concern. To this day, the disease remains largely mysterious, with yet no known specific markers to confirm diagnosis with a 100% certainty and no available treatment to stop or reverse the progression of the disease. To boost the development of new therapeutic approaches, there is a clear need for tangible advances in our understanding of AD, especially when it comes to early, reliable indicators of the presence and progression of the disease. Addressing this need, Dr. Julia Guiomar Niso Galán is investigating the hypothesis that an imbalance in neural activity is a prevalent indication of early pre-clinical Alzheimer's disease.

"Nowadays there's no effective treatment for AD, and many scientists think that this is because they start too late, when there's already irreversible damage in the brain", explains Dr. Julia Guiomar Niso Galán. "Current diagnosis approaches all target the accumulation of a molecule called Amyloid beta (Aβ) – one of AD's hallmarks –, as indication of probable AD"."My assumption is that by studying abnormal brain activity, we could get an earlier indicator of the disease", she summarises. Indeed, Dr. Julia Guiomar Niso Galán's hypothesis is that alterations of the excitatory and inhibitory mechanisms of neural activity precede the accumulation of Aβ, and subsequent formation into plaques. "One possible explanation could be that the deposition of Aβ plaques in the AD brain are a consequence of primarily perturbed neural activity, rather than vice-versa", says the researcher.

Detecting precocious abnormal neural activity in patients likely to develop AD

To test her hypothesis, Dr. Julia Guiomar Niso Galán will compare recordings of brain activity collected over the past 4 years on more than 500 participants. To study brain activity throughout the different stages of AD and probable AD, 4 categories of patients were chosen : declared AD patients, patients with mild cognitive impairment, subjects complaining about memory problems, and asymptomatic subjects. Using a neuroimaging technique, Dr. Julia Guiomar Niso Galán and her team will try to detect early manifestations of abnormal neural activity in the participants likely to develop the disease. "Owing to the type and number of participants screened, as well as the duration of the study, we know that part of the data we collected comes from patients who will develop AD in the future", explains Dr. Julia Guiomar Niso Galán. "By studying their brain activity before the clinical onset of the disease, we aim to identify reliable indicators for early diagnosis, and even prevention for people at risk"."Our ultimate goal is to measure a healthy person's risk of developing the disease", she adds.

Current estimations indicate that around 50 million people worldwide live with dementia, and the number is expected to double in the next 20 years. The epidemic represents a major public health concern, not to mention a devastating ordeal for patients and their families. By aiming to detect early pre-clinical manifestations of Alzheimer's disease, Dr. Julia Guiomar Niso Galán objective is to contribute to providing the means for better therapeutic interventions and prevention.