Behrooz Niknafs - Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
Ahmad Mehdipour - Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
Amaneh Mohammadi Roushandeh - Department of Anatomical Sciences, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.

Background: Melatonin, a reactive oxygen species (ROS) scavenger and an antioxidant, has been shown that can inhibit apoptosis. Administration of melatonin may improve embryo development in assisted reproductive technology (ART). Objective: The aim of this study was to evaluate the role of melatonin in inhibitionof spontaneous and induced apoptosis by Tumor Necrosis Factor Alph (TNF-α) and actinomycin-D during preimplantation development of mouse embryos. Materials and Methods: Female BALB/c mice were superovulated with pregnant mare serum gonadotropin (PMSG) followed by human chorionic gonadotropin(HCG), then allowed to mate with male mice. The resultant 2-cell embryos weredivided into six groups as follows: control (group I), melatonin (group II), actinomycin-D (group III), actinomycin-D + melatonin (group IV), TNF-α (groupV), and TNF-α + melatonin (group VI). We recorded the numbers and developmental rates of the 4-cell, 8-cell, morula and blastocyst embryos. Blastocystswere stained with acridine orange in order to assess for the embryo quality. Results: The group IV showed a significantly higher developmental rate ofblastocysts compared to group III (p<0.05). The number of dead blastomers was significantly decreased in group IV in comparison to group III (p<0.05). Both V andVI groups had a lower developmental rate and lesser quality of blastocysts compared with group I. There was no significant difference in the developmental rate ofblastocysts from group II compared to group I (p<0.05). Conclusion: Supplementation of embryo culture media with melatonin can improve the quality and developmental rate of embryos. Melatonin can prevent cell death that was induced by TNF- α and actinomycine-D.

Melatonin, Embryo, Actinomycine-D, TNF-α, Development