Melatonin treatment for prevention of oxidative stress: involving histopathological changes.
This study was undertaken to test the effect of irradiation on the histopathology of the hypothalamus and cerebral cortex. In addition, the probable effects of radiotherapy on the activities of antioxidant enzymes and levels of nitric oxide (NO) in the plasma were investigated as well. The effects of melatonin treatment on radiotherapy-based central nervous system (CNS) damage were also studied. For this purpose, the rats were randomized into four groups. The first group was the control group (sham-exposed group), the second group received only melatonin, the third group was irradiated and the fourth group received both melatonin and irradiation. Plasma samples of rats were collected for measuring the activities of superoxide dismutase (SOD), catalase (CAT) and the levels of NO. 24 h after the interventions, tissue samples were obtained from the hypothalamus and the cerebral cortex for the light microscopic investigations. These tissues were mostly affected by radiation. The results indicated that the application of radiation significantly enhanced the levels of plasma SOD and NO. On the other hand, melatonin pretreatment prevented the decrease in plasma CAT activity induced by irradiation. It was found that the application of melatonin could significantly prevent the irradiation-induced damages. Light microscopic results revealed that the damage of the CNS by radiation was prevented by the application of melatonin.
Department of Biology, Faculty of Sciences, University of Ankara, 06100 Tandogan, Ankara, Turkey. yildirim@science.ankara.edu.tr
O
O
Yildirim
S
S
Comoğlu
S
S
Yardimci
M
M
Akmansu
G
G
Bozkurt
M C
MC
Avunduk
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002374:Catalase / Q000097:blood / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D002540:Cerebral Cortex / Q000187:drug effects / Q000473:pathology / Q000528:radiation effects / Q000648:ultrastructure; D016166:Free Radical Scavengers / Q000378:metabolism / Q000528:radiation effects; D005720:Gamma Rays; D007031:Hypothalamus / Q000187:drug effects / Q000473:pathology / Q000528:radiation effects / Q000648:ultrastructure; D007928:Lethal Dose 50; D008550:Melatonin / Q000494:pharmacology*; D009569:Nitric Oxide / Q000097:blood / Q000378:metabolism / Q000528:radiation effects; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D011837:Radiation-Protective Agents / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000097:blood / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects
D000975:Antioxidants; D016166:Free Radical Scavengers; D011837:Radiation-Protective Agents; D009569:Nitric Oxide; D002374:Catalase; D013482:Superoxide Dismutase; D008550:Melatonin