Background: Lung is a radiosensitive organ. Studies have shown that exposure
of the lung to acute and high doses of radiation following inhalation of radioactive agents
or an accidental radiological event may lead to pneumonitis and fibrosis, which are associated
with a risk of death. So far, some agents have been studied for mitigation of pneumonitis
and fibrosis following exposure of murine lung tissues to ionizing radiation. In this
study, we aimed to detect the possible mitigatory effect of alpha-lipoic acid, resveratrol
and their combination on mice pneumonitis and fibrosis markers following irradiation.
Methods: 25 mice were divided into 5 groups: control, radiation; radiation plus alpha-lipoic
acid; radiation plus resveratrol; and radiation plus both resveratrol and alpha-lipoic acid. Mice
chest regions were irradiated with 18 Gy using a cobalt-60 gamma rays source. Treatments
started 24 h after irradiation and continued for two weeks. After 100 days, all mice were sacrificed
and their lung tissues removed for histopathological evaluation.
Results: Pathological study showed that exposure to radiation led to severe pneumonitis and
moderate fibrosis after 100 days. Both resveratrol and alpha-lipoic acid, as well as their
combination could mitigate pneumonitis and fibrosis markers. Although, resveratrol could
not mitigate infiltration of most inflammatory cells as well as inflammation and vascular
damage, alpha-lipoic acid and its combination were able to mitigate most damaged markers.
Conclusion: Alpha-lipoic acid and its combination with resveratrol were able to mitigate
fibrosis and pneumonitis markers in mice lung tissues following lung irradiation. Although
resveratrol has a protective effect on some markers, it has a weaker effect on lung injury.
In conclusion, our results suggest that the combination of resveratrol and alpha-lipoic acid
has a potent mitigatory effect compared to the single forms of these agents.