Ernst Titovets
Republican Research and Clinical Center of Neurology and Neurosurgery, Belarus
Title: Nanofluidics domain and computer simulation of water metabolism in the brain cortex
Biography
Biography: Ernst Titovets
Abstract
Brain water metabolism is involved in cell communication, transfer of signaling molecules, neurotransmitters, energy substrates and gases, heat exchange, etc. A number of pathologies including Alzheimer’s disease, idiopathic normal pressure hydrocephalus, migraine, traumatic brain injury and stroke, brain edema, etc. directly or indirectly arise from disorders in brain water metabolism.
There are the two mutually excluding basic views at present on brain water metabolism. A conventional theory maintains that the brain nanodimentional extracellular space presents a diffusion barrier to water movement. A new theory, based on an interdisciplinary approach and adopted here, makes it possible to treat the brain extracellular space as a nanofluidic domain where water flow is governed by the slip-flow mechanism. Contrary to the diffusion-barrier theory, the new one suggests fast water movement in the extracellular space.
Computer simulations of brain water metabolism have been carried out using a cuboid nanofluidic model. The model encompasses layers I-IIIb of the brain cortex and incorporates a central draining venule surrounded by four penetrating arterioles with the intervening capillary network. Aquaporin AQP4 presents a rate-limiting stage in the overall water transfer across the blood-brain barrier, i.e. between the blood and the brain parenchyma. The extracellular space is viewed as a nanofluidic domain. Computer simulations have produced a detailed 3D topography of brain water metabolism in terms of the volumetric water fluxes. Physiological and pathophysiological significance of the obtained results is discussed.