Efeitos do exercício físico sobre a microcirculação cerebral em um modelo de hipoperfusão cerebral em ratos

Abstract

The decrease in cerebral blood flow is an important risk factor for dementia and cognitive dysfunctions. Currently, exercise has been proposed as an ameliorative intervention to promote better functioning of brain, however the mechanisms are not yet clear. The aims of this study was to investigated the effects of an experimental model of cerebral hypoperfusion by bilateral occlusion of the common carotid (2VO), and the impact of early versus late short-term-moderate exercise on brain microcirculatory and inflammatory parameters in rats after brain hypoperfusion. This 2VO model was able to decrease brain functional capillary density and cerebral blood flow, increase leukocyte-endothelial interactions, and although not significant, induced increases of gene expression of NADPH oxidase and IL-6. Early intervention with physical exercise was able to reverse the alterations in brain functional capillary density and adherent leukocyte-endothelial interactions and increases of gene expression of eNOS. Although in the late phase of cerebral hipoperfusion functional and inflammatory changes in brain microcirculation are no longer evident, the late exercise intervention did not induced significant alterations in the analyzed parameters. We concluded that the cerebral microcirculatory and inflammatory changes are triggered in first days after 2VO and therefore, early exercise intervention can be considered a preventive approach for neurodegenerative diseases caused by chronic cerebral hipoperfusion