Original Article The Effect of Melatonin on Maturation, Glutathione Level and Expression of HMGB1 Gene in Brilliant

Objective: Nutrients and antioxidants in the medium of immature oocyte have a profound effect on maturation, fertilization and development of resulting embryos. In this study the ef-fects of melatonin as an antioxidant agent on maturation, glutathione level and expression of high mobility group box-1 (HMGB1) gene were evaluated in immature oocytes of mice stained with brilliant cresyl blue (BCB). Materials and Methods: In this experimental study, immature oocytes were harvested from ovaries of Naval Medical Research Institute (NMRI) mice. Oocytes were stained with 26 μM BCB for 90 minutes and transferred to in vitro maturation medium containing vary-ing doses of melatonin (10-12, 10-9, 10-6, 10-3 M) and without melatonin, for 22-24 hours. Maturation was monitored using an inverted microscope. Glutathione was assessed by monochlorobimane (MCB) staining and HMGB1 expression in mature oocyte was ana-lyzed using real-time polymerase chain reaction (PCR). Results: Melatonin in the concentration of 10-6 M had the most effect on maturation and HMGB1 expression of BCB+ oocytes (p<0.05). Meanwhile melatonin had no effects o