Gender based differences in radiation-induced lung injury in rats

Introduction: Pulmonary injury in patients receiving thoracic radiotherapy causes significant morbidity and mortality. There are many factors which influence the development of radiation-induced lung injury and the role of gender is not clearly known. This study aimed to show whether gender is a risk factor in the development of radiation-induced lung injury in the experimental lung radiation injury modeL. Method: A total of 31 male and 31 female Wistar albino rats aged 12 weeks were used in the study. Rats were grouped as; A1: Sham female control, A2: Radiotherapy (RT) female, A3: Oophorectomy female, A4: Oophorectomy + RT female, B1: Sham control male, B2: RT male, B3: Orchiectomy male B4: Orchiectomy+RT male. Radiotherapy groups received a single dose of 12 Gy RT for both lungs. After radiotherapy, all groups were followed for 16 weeks. Histopathologic examination, hydroxyproline measurements and TGF β1 expressions were examined in lung tissue. Results: All groups receiving radiotherapy were found to have increased lung tissue hydroxyproline content, histopathological evaluation of tissue damage and pulmonary fibrosis, and increased TGF β1 expression when compared to the control group (p<0.05). However, histopathological and biochemical markers of radiation lung injury were not different between male and female rats treated with radiotherapy. Conclusion: The results of our study suggest that gender may not a risk factor for the development of radiation-induced lung injury.