Effects of combination of melatonin and L-carnitine on in vitro maturation in mouse oocytes: An experimental study.

BACKGROUND

Melatonin and L-carnitine are free radical scavengers with antiapoptotic and antioxidant properties that improve oocyte development.

OBJECTIVE

This study aimed to find the possible effect of combining 2 antioxidant agents of melatonin and L-carnitine on oocyte morphology, maturation, apoptosis, and expression of bone morphogenetic protein 15 () and growth differentiation factor 9 () genes in a mice model.

MATERIALS AND METHODS

To overstimulation, 60 female NMRI mice were injected intraperitoneally using mare serum gonadotropin. On day 2 post-injection, 70 cumulus-oocyte complexes were collected from each mouse. The collected oocytes randomly were then divided into 4 groups including, the control, melatonin, L-carnitine, and melatonin + L-carnitine groups. The morphology and maturation rate of the oocytes was evaluated using a light microscope. Apoptosis was identified by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and the expression of and growth and differentiation factor genes was also evaluated by real-time polymerase chain reaction.

RESULTS

Oocyte diameter significantly was increased in combination treatment of L-carnitine and melatonin compared to other groups (p 0.05). L-carnitine group showed the highest mean percentage of oocyte cytoplasmic pattern. Results of the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling indicated that the lowest apoptosis rate belonged to the melatonin + L-carnitine group. Moreover, the combination groups showed the highest number of oocytes and maturation rate. The and genes were significantly upregulated in all treatment groups compared to the control group.

CONCLUSION

Our results suggested a combination of melatonin + L-carnitine administration as a more effective choice for in vitro promotion of oocyte maturation.