Ionizing radiation causes its
biological effects mainly through oxidative damage induced by
reactive oxygen species. Previous studies showed that
ozone oxidative preconditioning attenuated pathophysiological events mediated by
reactive oxygen species. As inhalation of
ozone induces
lung injury, the aim of this study was to examine whether
ozone oxidative preconditioning potentiates or attenuates the effects of irradiation on the lung. Rats were subjected to total body irradiation, with or without treatment with
ozone oxidative preconditioning (0.72 mg/kg). Serum proinflammatory
cytokine levels, oxidative damage markers, and histopathological analysis were compared at 6 and 72 h after total body irradiation. Irradiation significantly increased lung
malondialdehyde levels as an end-product of lipoperoxidation. Irradiation also significantly decreased lung
superoxide dismutase activity, which is an
indicator of the generation of oxidative stress and an early protective response to oxidative damage.
Ozone oxidative preconditioning plus irradiation significantly decreased
malondialdehyde levels and increased the activity of
superoxide dismutase, which might indicate protection of the lung from radiation-induced
lung injury. Serum
tumor necrosis factor alpha and
interleukin-1 beta levels, which increased significantly following total body irradiation, were decreased with
ozone oxidative preconditioning. Moreover,
ozone oxidative preconditioning was able to ameliorate radiation-induced
lung injury assessed by histopathological evaluation. In conclusion,
ozone oxidative preconditioning, repeated low-dose intraperitoneal administration of
ozone, did not exacerbate radiation-induced
lung injury, and, on the contrary, it provided protection against radiation-induced lung damage.