title: Neuroprotective effect of hyperbaric oxygen therapy in a juvenile rat model of repetitive mild traumatic brain injury.
abstract: Repetitive mild traumatic brain injury (rmTBI) is an important medical concern for adolescent athletes that can lead to long-term disabilities. Multiple mild injuries may exacerbate tissue damage resulting in cumulative brain injury and poor functional recovery. In the present study, we investigated the increased brain vulnerability to rmTBI and the effect of hyperbaric oxygen treatment using a juvenile rat model of rmTBI. Two episodes of mild cortical controlled impact (3 days apart) were induced in juvenile rats. Hyperbaric oxygen (HBO) was applied 1 hour/day × 3 days at 2 atmosphere absolute consecutively, starting at 1 day after initial mild traumatic brain injury (mTBI). Neuropathology was assessed by multi-modal magnetic resonance imaging (MRI) and tissue immunohistochemistry. After repetitive mTBI, there were increases in T2-weighted imaging-defined cortical lesions and susceptibility weighted imaging-defined cortical microhemorrhages, correlated with brain tissue gliosis at the site of impact. HBO treatment significantly decreased the MRI-identified abnormalities and tissue histopathology. Our findings suggest that HBO treatment improves the cumulative tissue damage in juvenile brain following rmTBI. Such therapy regimens could be considered in adolescent athletes at the risk of repeated concussions exposures.
authors.affiliation: Department of Anesthesiology, School of Medicine, Loma Linda University, Loma Linda, CA, USA; Department of Basic Sciences, Division of Physiology, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Lei
authors.initials: L
authors.lastname: Huang
authors.affiliation: Department of Pediatrics, School of Medicine, Loma Linda University, Loma Linda, CA, USA; Cell, Molecular and Developmental Biology Program, University of California Riverside, Riverside, CA, USA; Division of Interdisciplinary Studies, School of Behavioral Health, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Andre
authors.initials: A
authors.lastname: Obenaus
authors.affiliation: Department of Pediatrics, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Hamer
authors.affiliation: Department of Anesthesiology, School of Medicine, Loma Linda University, Loma Linda, CA, USA; Department of Basic Sciences, Division of Physiology, School of Medicine, Loma Linda University, Loma Linda, CA, USA; Department of Neurosurgery, Loma Linda University, Loma Linda, CA, USA.
authors.forename: John H
authors.identifier: 0000-0002-4319-4285
authors.initials: JH
authors.lastname: Zhang
keywords: T2-weighted imaging; adolescent; concussion; diffusion weighted imaging; gliosis; magnetic resonance imaging; rat; susceptibility weighted imaging