Rôle des lésions cholinergiques mésopontiques dans les troubles exécutifs de la maladie de Parkinson: une étude d'imagerie cérébrale par tomographie par émission de positons avec le F18-Fluoroethoxybenzovesamicol

 

Camille Legault-Denis

CUSM-Institut neurologique de Montréal

 

Domaine : Vieillissement

Programme : Formation de maîtrise

Concours 2016-2017

Partenaire:

Parkinson Québec

Parkinson's disease (PD) is a neurodegenerative disorder affecting over 100,000 Canadians (Parkinson Society Canada). Age is a risk factor for PD, and prevalence is expected to increase with the aging population. Currently, there is no treatment that can stop the progression of the disease, and the etiology still remains unknown. Symptoms of PD include at rest tremor, rigidity, and difficulty to initiate movements. These symptoms are associated to a lack of a brain chemical messenger called Dopamine. Current PD treatments are aimed to compensate for this Dopamine deficiency. However, these treatments have no effect on other symptoms such as the Mild Cognitive Impairments (MCI) frequently encountered in PD, which are characterised by deficits in attention, planning abilities, and working memory. There are some evidences suggesting that MCI involves a depletion of another chemical messenger of the brain named Acetylcholine (Ach).

The 18F-fluoroethoxybenzovesamicol (FEOBV) is a radioactive compound recently synthesized by our team in order to be used for brain imaging, using positron emission tomography (PET). The FEOBV is believed to label specifically the cells of the brain that produce ACh. Results from our animal and post mortem studies in human suggest that FEOBV has the potential to detect ACh changes in the brain. However, this has never been demonstrated in a living human.

The aim of this study is therefore to demonstrate that FEOBV used with PET will be able to quantify Ach depletion in the brain of patients with PD. If so, we will search for relationship between this depletion and the MCI. As a whole, this study will allow a better understanding of the pathophysiology of MCI in PD, which may in turn lead to the development of new treatments of this clinical condition.