NPP Seminar - Professor David Attwell, University College London

Academic Host: Stephanie Schorge

Abstract: Brain blood flow is regulated to ensure adequate power for neuronal computation. Blood flow is increased to areas where neurons are active, and this increase underlies non-invasive brain imaging using BOLD fMRI. I will demonstrate that neuronal activity largely increases cerebral blood flow by dilating capillaries via pericytes, that this involves signalling via astrocytes, and that dilation of capillaries and dilation of arterioles are mediated by different messengers.

Ischaemia leads to pericytes constricting and dying, thus producing a long-lasting decrease of blood flow. I will show that similar events occur in Alzheimer’s Disease, when pericyte-mediated constriction is sufficient to approximately halve blood flow and in humans increases with the severity of the disease. A similar pericyte-mediated constriction may occur in Covid-19 and in diabetes. Pericyte constriction is therefore a therapeutic target in stroke, Alzheimer’s disease and perhaps Covid-19 and diabetes.