Oncology Publications

Title

Partial volume rat lung irradiation: the protective/mitigating effects of Eukarion-189, a superoxide dismutase-catalase mimetic.

Document Type

Article

Publication Date

5-1-2006

Journal

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology

Volume

79

Issue

2

First Page

231

Last Page

238

URL with Digital Object Identifier

http://dx.doi.org/10.1016/j.radonc.2006.03.017

Abstract

BACKGROUND AND PURPOSE: The purpose of the current study was to elucidate the protective/mitigating effects of a SOD-catalase mimetic, Eukarion-189 (EUK-189), on DNA damage in rat lung following irradiation. The particular focus of these studies was the efficacy of EUK-189 when given after irradiation (mitigation).

PATIENTS AND METHODS: We exposed whole or lower lungs of female Sprague-Dawley rats to doses ranging from 10 to 20.5 Gray (Gy) of (60)Co gamma rays. Animals in the EUK-189 treated groups received 2 or 30 mg/kg intraperitoneally (i.p.) at various times postirradiation (PI). A micronucleus assay was used to examine DNA damage at various times up to 16 weeks PI.

RESULTS: Our results indicated that EUK-189 administration after irradiation is effective at reducing micronucleus formation in lung fibroblasts at various times following radiation exposure. Treatment with EUK-189 in the first 3 days after thoracic irradiation did not, however, modify the dose required to cause severe morbidity at 2-3 months after irradiation.

CONCLUSIONS: The protection produced when Eukarion-189 was given shortly after irradiation suggests that DNA damage observed in the lung may be caused by chronic production of ROS induced by a chronic inflammatory response initiated by the radiation treatment. We speculate that our failure to observe protection against severe morbidity at 2-3 months may be because our treatment regime only blocked the initial wave of ROS production and that treatment needs to be more prolonged to suppress the effects of a chronic inflammatory response.

Notes

PMID:16675053