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Published on: August 23, 2019
Melatonin prevents possible radiotherapy-induced thyroid injury
Mitat Arıcıgil1, Mehmet Akif Dündar1, Abitter Yücel2
1a Department of Otorhinolaryngology , Meram Faculty of Medicine, Necmettin Erbakan University , Konya , Turkey.
Purpose:
We aimed to investigate the protective effect of melatonin in radiotherapy-induced thyroid gland injury in an experimental rat model.
Materials And Methods:
Thirty-two rats were divided into four groups: the control group, melatonin treatment group, radiotherapy group and melatonin plus radiotherapy group. The neck region of each rat was defined by simulation and radiated with 2 Gray (Gy) per min with 6-MV photon beams, for a total dose of 18 Gy. Melatonin was administered at a dose of 50 mg/kg through intraperitoneal injection, 15 min prior to radiation exposure. Thirty days after the beginning of the study, rats were decapitated and analyses of blood and thyroid tissue were performed.
Results:
Tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β), thiobarbituric acid reactive substances (TBARS) and nitric oxide (NO) levels in the radiotherapy group were significantly higher than those in the melatonin plus radiotherapy group (p < .05), whereas interleukin-10 (IL-10) and glutathione (GSH) values were higher in the melatonin plus radiotherapy group (p < .05). The infiltration of inflammatory cells and percentage of apoptosis in the radiotherapy group were significantly higher than those in the melatonin plus radiotherapy group (p < .05).
Conclusions:
Melatonin helped protect thyroid gland structure against the undesired cytotoxic effects of radiotherapy in rats.
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