- - - MSc, Department of Radiology, Faculty of Paramedicine, Shiraz University of Medical Sciences, Shiraz, Iran
- - - PhD, Department of Radiology, Faculty of Paramedicine, Shiraz University of Medical Sciences, Shiraz, Iran
- - - MSc, Department of Radiology, Faculty of Paramedicine, Shiraz University of Medical Sciences, Shiraz, Iran
- - - PhD, Department of Radiology, Faculty of Paramedicine, Shiraz University of Medical Sciences, Shiraz, Iran

Background: The heart is the major dose-limiting organ for radiotherapy of malignant tumor in the mediastanal region. Objective: This study aims to investigate the radio protective effects of Hesperidin (HES) as a natural flavonoid after localized irradiation of the rat’s mediastinum region.Material and Methods: In this experimental study, we divided sixty male rats into ۴ groups (n=۱۵). First group: Sham which received PBS; second group: Hesperidin only (۱۰۰ mg/kg/day orally) for one week; third group: Radiation that received single dose of ۲۰ Gy gamma radiation using Co-۶۰ unit and the forth group: Radiation+HES that underwent the same dose of radiation and received HES for ۷ days prior irradiation. Each group was divided in two branches. Early sampling from subgroup one was done ۴-۶ hours after irradiation to determine troponin-۱ level changes. Rats of second subgroups were killed ۵۶ days after irradiation for histopathological evidence. Results: In radiation group, troponin -۱ serum level had a significant increase in comparison with sham group (p <۰.۰۵). Histopathological evaluation of second subgroup showed there was a significant difference between sham and radiation group in some parameters. Inflammation (p=۰.۰۰۸), pericardial effusion (P=۰.۰۰۱), and vascular plaque (P=۰.۰۰۱) had an increase in the irradiation group. Oral administration of hesperidin significantly decreased all the above factors when was compared with irradiation group (P>۰.۰۱۶). Conclusion: Oral administration of Hesperidine for seven days prior radiotherapy may decrease troponin-۱ and cardiac injury due to radiation.

Radiation, Heart Injury, Hesperidin