Supplementation of culture media with vitamin E improves mouse antral follicle maturation and embryo development from vitrified ovarian tissue.

Abstract

The aim of this study was to evaluate the effects of preventive vitamin E (α-tocopherol) on antral follicle development and embryogenesis of oocytes obtained after vitrification of mouse ovarian tissue. Female Balb/c mice were killed by cervical dislocation after the injection of pregnant mare's serum gonadotrophin (10 IU) and their ovaries were randomly divided into three groups: control or non-vitrified (n = 10), vitrification 1 (5, 10% ethylene glycol +5, 10% dimethylsulfoxide) (n = 15), and vitrification 2 (10, 15% ethylene glycol+10, 15% dimethylsulfoxide) (n = 15) with ascending concentration of cryoprotectants. After toxicity tests and vitrification-warming, mechanically isolated antral follicles were cultured in α-minimum essential medium, which was supplemented with or without α-tocopherol (100 μM). The follicular maturation rates and embryo development were collected and assessed. Also, the viability, morphology and ultrastructure of derived antral follicles from vitrified ovaries were analyzed. The morphology and ultrastructure of follicles were well preserved in the vitrified groups and α-tocopherol supplementation of culture media significantly increased the proportion of oocytes that reached metaphase II blastocyst rates compared to non-α-tocopherol supplemented media (P < 0.01). Vitamin E improves in vitro maturation rates and blastocyst rates of oocytes that are isolated from vitrified ovarian tissue.