Renin-Angiotensin System 24 hours after mild traumatic brain injury: a case- control study

Abstract

Background: The Renin-Angiotensin System (RAS) has been associated with several neuropathologies, including traumatic brain injury (TBI). Objectives: Assess the relationship between RAS and mild TBI within 24 hours after trauma. Design and setting: A case-control study developed by the Federal University of Minas Gerais and conducted at the Hospital João XXIII, Belo Horizonte, Minas Gerais, Brazil. Methods: Sociodemographic data and blood samples were collected from 52 individuals, of whom 28 suffered mild TBI in the 24 hours prior to collection and 24 healthy individuals made up the control group. The serum was used to measure the components of the RAS. Results: There were no significant sociodemographic differences between groups regarding to sex and age (p=0.782; p=0.077). Of the experimental group, 15 individuals reported loss of consciousness and 11 reported previous TBI. The experimental group showed significantly higher concentrations of angiotensin II (p=0.0234) and angiotensin-(1-7) (p=0.0225) and significantly lower concentrations of angiotensin converting enzyme (ACE) (p=0.0004) and ACE2 (p=0.0047). Conclusion: RAS seems to be involved in the pathophysiology of the hyperacute phase of mild TBI and the study of its components may contribute to identify prognostic biomarkers and new therapeutic targets for patients victims of TBI.