Physiopathologies de la dépression et du suicide: fondements neuroanatomiques

Chercheurs-boursiers - Junior 2 | Concours 2012-2013

Naguib Mechawar

Centre de recherche de l'Hôpital Douglas


Domaine : Neurosciences, santé mentale et toxicomanies

According to the World Health Organization, major depression affects approximately 121 million people worldwide and is ranked as one of the leading causes of disability. The most dramatic consequence of this illness for our society, however, is that between 7 and 15% of patients will commit suicide. It is currently thought that depression may arise from altered cerebral plasticity, particularly in brain regions involved in mood and emotion. This has been the focus of many investigations at the macroscopic level. In particular, brain imaging studies have provided evidence for depression-related functional and gross morphological alterations in some key regions, such as the prefrontal cortex, anterior cingulate cortex, hippocampus and amygdala. A better knowledge of underlying cellular alterations is required if we are to better understand how communication and plasticity are affected in the brains of depressed individuals. Unfortunately, the fine neuroanatomy of this psychiatric disorder remains a relatively unchartered field of investigation. My research program aims mainly at studying the fine organization of brain cells and circuits in regions involved in mood regulation. To carry out my research projects, I have access to well-characterized postmortem brain samples (Quebec Brain Bank) from individuals who suffered from depression and others who did not have any brain illness. In addition, we use in my laboratory animal models of depression to further investigate, for instance, the consequences of chronic stress on the brain, or cerebral mechanisms involved in antidepressant response. These studies are expected to lead to a better understanding of the cellular and molecular underpinnings of major depression and suicide.