RESUMO
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 4 groups (n=15). First group: Sham which received PBS; second group: Hesperidin only (100 mg/kg/day orally) for one week; third group: Radiation that received single dose of 20 Gy gamma radiation using Co-60 unit and the forth group: Radiation+HES that underwent the same dose of radiation and received HES for 7 days prior irradiation. Each group was divided in two branches. Early sampling from subgroup one was done 4-6 hours after irradiation to determine troponin-1 level changes. Rats of second subgroups were killed 56 days after irradiation for histopathological evidence. RESULTS: In radiation group, troponin -1 serum level had a significant increase in comparison with sham group (P<0.05). Histopathological evaluation of second subgroup showed there was a significant difference between sham and radiation group in some parameters. Inflammation (p=0.008), pericardial effusion (P=0.001), and vascular plaque (P=0.001) had an increase in the irradiation group. Oral administration of hesperidin significantly decreased all the above factors when was compared with irradiation group (P>0.016). CONCLUSION: Oral administration of Hesperidine for seven days prior radiotherapy may decrease troponin-1 and cardiac injury due to radiation.
