Total-body irradiation of postpubertal mice with (137)Cs acutely compromises the microarchitecture of cancellous bone and increases osteoclasts.
Ionizing radiation can cause substantial tissue degeneration, which may threaten the long-term health of astronauts and radiotherapy patients. To determine whether a single dose of radiation acutely compromises structural integrity in the postpubertal skeleton, 18-week-old male mice were exposed to (137)Cs gamma radiation (1 or 2 Gy). The structure of high-turnover, cancellous bone was analyzed by microcomputed tomography (microCT) 3 or 10 days after irradiation and in basal controls (tissues harvested at the time of irradiation) and age-matched controls. Irradiation (2 Gy) caused a 20% decline in tibial cancellous bone volume fraction (BV/TV) within 3 days and a 43% decline within 10 days, while 1 Gy caused a 28% reduction 10 days later. The BV/TV decrement was due to increased spacing and decreased thickness of trabeculae. Radiation also increased ( approximately 150%) cancellous surfaces lined with tartrate-resistant, acid phosphatase-positive osteoclasts, an index of increased bone resorption. Radiation decreased lumbar vertebral BV/TV 1 month after irradiation, showing the persistence of cancellous bone loss, although mechanical properties in compression were unaffected. In sum, a single dose of gamma radiation rapidly increased osteoclast surface in cancellous tissue and compromised cancellous microarchitecture in the remodeling appendicular and axial skeleton of postpubertal mice.
Kondo
Hisataka
H
Department of Radiation Oncology, University of California, Irvine, California, USA.
Searby
Nancy D
ND
Mojarrab
Rose
R
Phillips
Jonathan
J
Alwood
Joshua
J
Yumoto
Kenji
K
Almeida
Eduardo A C
EA
Limoli
Charles L
CL
Globus
Ruth K
RK
D000375:Aging / Q000473:pathology*; D000818:Animals; D001835:Body Weight / Q000528:radiation effects; D015519:Bone Density / Q000528:radiation effects; D001862:Bone Resorption / Q000000981:diagnostic imaging; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology / Q000528:radiation effects*; D002588:Cesium Radioisotopes; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays / Q000009:adverse effects; D008297:Male; D051379:Mice; D009929:Organ Size / Q000528:radiation effects; D010010:Osteoclasts / Q000473:pathology / Q000528:radiation effects*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014916:Whole-Body Irradiation / Q000009:adverse effects*
D002588:Cesium Radioisotopes