The effect of adding Rosmarinic and Ascorbic acids to vitrification media on fertilization rate of the mice oocyte: An experimental study

Background: Oocytes vitrification is a pivotal step for the widespread and safekeepingof animal genetic resources. Oocytes endure notable morphological and functionaldamage during cryopreservation. Oxidative stress is one of the adverse effects thatvitrification imparts on oocytes.Objective: In the present study, we investigated the antioxidant effect of Rosmarinicand Ascorbic acids on the quality and fertilizing ability of frozen-thawed mice oocyte.Materials and Methods: In this experimental study, germinal vesicle oocytes obtainedfrom two-months-old (30–40gr) NMRI mice were randomly divided into four groups.The basic cryoprotectants were 7.5% (v/v) ethylene glycol+7.5% (v/v) Propanediol asan equilibration media. Vitrification medium contained 15% (v/v) ethylene glycol+15%(v/v) propanediol, and 0.5 M sucrose. In the first group (Control), nothing was addedto vitrification mediums, whereas, in the second and third groups, 0.5 mmol/L ofAscorbic acid and 105 μmol/L of Rosmarinic acid were added into vitrification medium,respectively. The cumulative concentration of Rosmarinic and Ascorbic acids wereadded to group 4. Mouse oocytes were vitrified and preserved for one month. Thethawed oocytes were transferred into the α-MEM medium (Alpha Minimum EssentialMedium) and maintained in this medium for 24 hr, to be matured and reach themetaphase II stage.Results: The addition of Rosmarinic and Ascorbic acids to the vitrification solutionimproved the survival, maturation of Germinal vesicles, fertilization rate, and finallydevelopment to 4-cell stage. Maturation rates to 4-cell stage for Ascorbic acid, Rosmarinicacid, and both of them together were 80%, 80.76%, and 86.61%, respectively.Conclusion: These results indicate that the addition of a cumulative concentration of0.5 mmol/L Ascorbic acid and 105 μmol/L of Rosmarinic acid to the cryopreservationsolution for the mouse immature oocytes would be of significant value (p< 0.01).

Keywords:

Vitrification , Antioxidant , Fertilization