Protection of Oligodendrocytes Through Neuronal Overexpression of the Small GTPase Ras in Hyperoxia-Induced Neonatal Brain Injury

Bibliographic Details
Title: Protection of Oligodendrocytes Through Neuronal Overexpression of the Small GTPase Ras in Hyperoxia-Induced Neonatal Brain Injury
Authors: Meray Serdar, Josephine Herz, Karina Kempe, Elke Winterhager, Holger Jastrow, Rolf Heumann, Ursula Felderhoff-Müser, Ivo Bendix
Source: Frontiers in Neurology, Vol 9 (2018)
Publisher Information: Frontiers Media S.A., 2018.
Publication Year: 2018
Collection: LCC:Neurology. Diseases of the nervous system
Subject Terms: preterm birth, brain injury, hyperoxia, neuronal Ras, white matter injury, neuroprotection, Neurology. Diseases of the nervous system, RC346-429
More Details: Prematurely born infants are highly susceptible to various environmental factors, such as inflammation, drug exposure, and also high environmental oxygen concentrations. Hyperoxia induces perinatal brain injury affecting white and gray matter development. It is well known that mitogen-activated protein kinase signaling is involved in cell survival, proliferation, and differentiation. Therefore, we aim to elucidate cell-specific responses of neuronal overexpression of the small GTPase Ras on hyperoxia-mediated brain injury. Six-day-old (P6) synRas mice (neuronal Ras overexpression under the synapsin promoter) or wild-type littermates were kept under hyperoxia (80% oxygen) or room air (21% oxygen) for 24 h. Apoptosis was analyzed by Western blot of cleaved Caspase-3 and neuronal and oligodendrocyte degeneration via immunohistochemistry. Short-term differentiation capacity of oligodendrocytes was assessed by quantification of myelin basic protein expression at P11. Long-lasting changes of hyperoxia-induced alteration of myelin structures were evaluated via transmission electron microscopy in young adult animals (P42). Western blot analysis of active Caspase-3 demonstrates a significant upregulation in wild-type littermates exposed to hyperoxia whereas synRas mice did not show any marked alteration of cleaved Caspase-3 protein levels. Immunohistochemistry revealed a protective effect of neuronal Ras overexpression on neuron and oligodendrocyte survival. Hyperoxia-induced hypomyelination in wild-type littermates was restored in synRas mice. These short-term protective effects through promotion of neuronal survival translated into long-lasting improvement of ultrastructural alterations of myelin sheaths in mice with neuronal overexpression of Ras compared with hyperoxic wild-type mice. Our data suggest that transgenic increase of neuronal Ras activity in the immature brain results in secondary protection of oligodendrocytes from hyperoxia-induced white matter brain injury.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1664-2295
Relation: http://journal.frontiersin.org/article/10.3389/fneur.2018.00175/full; https://doaj.org/toc/1664-2295
DOI: 10.3389/fneur.2018.00175
Access URL: https://doaj.org/article/81ab30f2e0614968beabbc241ad6f1b8
Accession Number: edsdoj.81ab30f2e0614968beabbc241ad6f1b8
Database: Directory of Open Access Journals
More Details
ISSN:16642295
DOI:10.3389/fneur.2018.00175
Published in:Frontiers in Neurology
Language:English