Failure of drainage of fluid from the brain along the walls of blood vessels in vascular dementia

Stroke Association Priority Programme Award (vascular dementia) –  £245,198.00

Cerebral small vessel disease (SVD) is a key feature of vascular dementia, radiologically defined by the presence of white matter hyperintensities, lacunar infarcts, microbleeds and perivascular spaces.  Cerebral arteriolosclerosis resulting in loss of elasticity and segmental disorganisation of the arterial wall leads to damage of the deep white matter.  The primary functions of penetrating and perforating cerebral arteries supplying blood and drainage of fluid and solutes from the parenchyma along IPAD pathways are impaired.  In this project, using animal models and post-mortem brain tissue from stroke survivors with SVD (CogFAST study) along with light sheet 3D microscopy and post-mortem MRI, we will assess the immunocytochemical pattern of distribution of AQP4, α-dystrobrevin and β-dystroglycan.  We will then test the hypotheses that 1) disruption in the anchoring system of the basement membranes such as that observed in α-dystrobrevin knock-out mice and 2) disruption of gliovascular end feet tracked by aquaporin 4 (AQP4) knock-out mice there is failure of perivascular clearance of fluid from the deep gray matter and the corpus callosum.  Our aim is to demonstrate that failure of perivascular drainage of fluid from the brain is a mechanism underlying SVD and this could be targeted therapeutically.