Author/Authors :
Tahamtan، Raziyeh نويسنده Department of Biophysics and Biochemistry, Cellular and Molecular Biology Research Centre, Babol University of Medical Sciences, Babol, Iran , , Shabestani Monfared، Ali Ali نويسنده Cellular & Molecular Biology Research Center (CMBRC), Babol University of Medical Sciences, Babol, Iran Shabestani Monfared, Ali Ali , Tahamtani، Yasser نويسنده Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran , , Tavassoli، Alireza نويسنده Department of Pathology, Fasa University of Medical Sciences, Fasa, Iran , , Akmali، Maasoomeh نويسنده Department of Biochemistry, Faculty of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran , , Mosleh-Shirazi، Mohammad Amin نويسنده , , Naghizadeh، Mohammad-Mehdi نويسنده , , Ghasemi، Danial نويسنده Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran , , Keshavarz، Mojtaba نويسنده Department of Pharmacology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran , , Haddadi، Gholam Hassan نويسنده Department of Medical Physics, Fasa University of Medical Sciences, Fasa, Iran ,
Abstract :
Objective: Free radicals generated by ionizing radiation attack various cellular components
such as lipids. The lung is a very radiosensitive organ and its damage is a doselimiting
factor in radiotherapy treatments. Melatonin (MLT), the major product of the pineal
gland acts as a radioprotective agent. This study aims to investigate the radioprotective
effects of MLT on malondialdehyde (MDA) levels and histopathological changes in irradiated
lungs.
Materials and Methods: In this experimental study, a total of 62 rats were divided into
five groups. Group 1 received no MLT and radiation (unT), group 2 received oral MLT
(oM), group 3 received oral MLT and their thoracic areas were irradiated with 18 Gy (oMR),
group 4 received MLT by intraperitoneal (i.p.) injection and their thoracic areas were
irradiated with 18 Gy (ipM-R), group 5 received only 18 Gy radiation in the thoracic area
(R). Following radiotherapy, half of the animals in each group were sacrificed at 48 hours
for evaluation of lipid peroxidation and early phase lung injuries. Other animals were sacrificed
in the eighth week of the experiment for evaluation of the presence of late phase
radiation induced lung injuries.
Results: Pre-treatment of rats with either i.p injection (p < 0.05) and oral administration of
MLT (p < 0.001) significantly reduced MDA levels in red blood cell (RBC) samples compared
to the R group. Furthermore, i.p. injection of MLT decreased MDA levels in plasma
and tissue (p < 0.05). In the early phase of lung injury, both administration of MLT significantly
increased lymphocyte (p < 0.05) and macrophage frequency (p < 0.001). MLT reduced
the lung injury index in the lungs compared to the R group (p < 0.05).
Conclusion: The result of this study confirms the radioprotective effect of MLT on lipid
peroxidation, and in both early and late phases of radiation induced lung injuries in an
animal model.
