Introduction: Doxorubicin is one of the major antitumor treatment. The essential limiting factor of using this drug is the production of cardiotoxicity. However, melatonin is a powerful antioxidant that may protect the heart.
Aim: This study was aimed to study possible protective role of melatonin in adult male albino rats following doxorubicin administration
Material and Method: In this study, 40 adult male albino rats were used. They were divided into four groups (10 rats for each): control group, Melatonin group, Doxorubicin group and Doxorubicin & Melatonin group. Heart specimens were obtained at the end and processed.
Results: Light studies showed degenerative changes. Some fibers showed dark acidophilic cytoplasm and pyknotic nuclei. Apoptosis were detected where the nuclei varying from peripheral condensation of chromatin up to pyknosis, confirmed with positively caspase-3 activity. Dilatation of the vessels with mononuclear cellular infiltrations and deposited collagen fibers were seen. Ultrastructural examination showed disarrangement of the sarcomeres, disruption of microfilaments and Z- line, the number and size of mitochondria apparently increased, dilated SER and T tubules were also noticed. The presence of oval shaped cells (Telocyte) with thin long processes (Telopodes) were detected.
Conclusion: From this study, it was concluded that, melatonin markedly suppressed cardiomyopathy induced by doxorubicin.