Sage Begolly1, Peter G Shrager2, John A Olschowka3, Jacqueline P Williams4, M Kerry O'Banion5. 1. Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York. 2. Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York; Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, New York. 3. Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York. 4. Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; Department of Radiation Oncology, University of Rochester School of Medicine and Dentistry, Rochester, New York. 5. Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York; Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, New York. Electronic address: Kerry_OBanion@URMC.Rochester.edu.
Abstract
PURPOSE: To determine the late effects of fractionated versus single-dose cranial radiation on murine white matter. METHODS AND MATERIALS: Mice were exposed to 0 Gy, 6 × 6 Gy, or 1 × 20 Gy cranial irradiation at 10 to 12 weeks of age. Endpoints were assessed through 18 months from exposure using immunohistochemistry, electron microscopy, and electrophysiology. RESULTS: Weight gain was temporarily reduced after irradiation; greater loss was seen after single versus fractionated doses. Oligodendrocyte progenitor cells were reduced early and late after both single and fractionated irradiation. Both protocols also increased myelin g-ratio, reduced the number of nodes of Ranvier, and promoted a shift in the proportion of small, unmyelinated versus large, myelinated axon fibers. CONCLUSIONS: Fractionation does not adequately spare normal white matter from late radiation side effects.
PURPOSE: To determine the late effects of fractionated versus single-dose cranial radiation on murine white matter. METHODS AND MATERIALS: Mice were exposed to 0 Gy, 6 × 6 Gy, or 1 × 20 Gy cranial irradiation at 10 to 12 weeks of age. Endpoints were assessed through 18 months from exposure using immunohistochemistry, electron microscopy, and electrophysiology. RESULTS:Weight gain was temporarily reduced after irradiation; greater loss was seen after single versus fractionated doses. Oligodendrocyte progenitor cells were reduced early and late after both single and fractionated irradiation. Both protocols also increased myelin g-ratio, reduced the number of nodes of Ranvier, and promoted a shift in the proportion of small, unmyelinated versus large, myelinated axon fibers. CONCLUSIONS: Fractionation does not adequately spare normal white matter from late radiation side effects.
Authors: Rachel N Andrews; Gregory O Dugan; Ann M Peiffer; Gregory A Hawkins; David B Hanbury; J Daniel Bourland; Robert E Hampson; Samuel A Deadwyler; J Mark Clinea Journal: Radiat Res Date: 2019-01-29 Impact factor: 2.841