Vitamin E supplementation may negatively affect preimplantation development and mitochondrial ultrastructure of vitrified murine embryos

Objective:To observe the effects of vitamin E on post-vitrification preimplantation development,gross morphology as well as mitochondrial distribution and ultrastructure.Methods:Twenty-four female C57BL/6NTac mice,aged 12-16 weeks,were randomly divided into four groups.Group A did not receive any treatment and served as the control group.Group B was treated with corn oil stripped of tocopherols and served as the vehicle group.Group C was treated with 60 mg/kg body weight of tocotrienol-rich-fraction with corn oil stripped of tocopherols.Group D was treated with 60 mg/kg body weight of alpha-tocopherol with corn oil stripped of tocopherols.All treatments were administered orally for 7 consecutive days.After superovulation and mating with fertile males,2-cell stage embryos were harvested for vitrification.Post vitrification development in vitro,gross morphology and ultrastructure were compared between groups.Results:The number of 2 and 8-cell embryo,and blastocysts in the treatment and control groups were not significantly different(P>0.05).Following vitrification,all 2-cell embryos had equal-sized blastomeres and intact zona pellucida.Mitochondrial aggregation toward the perinuclear region was seen in all of the treatment groups.Both groups C and D had vacuolated mitochondria,which was reflected in the trend of preimplantation development reduction.Conclusions:Vitamin E supplementation of 60 mg/kg body weight does not improve the viability of healthy embryos according to this study.As a result,the most effective dose of vitamin E supplementation may be determined by the initial quality of the embryos.

Glutathione (GSH) improves sperm quality and testicular morphology in streptozotocin-induced diabetic mice

Diabetes mellitus(DM)is known to cause reproductive impairment.In men,it has been linked to altered sperm quality and testicular damage.Oxidative stress(OS)plays a pivotal role in the development of DM complications.Glutathione(GSH)is a part of a nonenzymatic antioxidant defense system that protects lipid,protein,and nucleic acids from oxidative damage.However,the protective effects of exogenous GSH on the male reproductive system have not been comprehensively examined.This study determined the impact of GSH supplementation in ameliorating the adverse effect of type 1 DM on sperm quality and the seminiferous tubules of diabetic C57BL/6NTac mice.GSH at the doses of 15 mg kg^(-1)and 30 mg kg^(-1)was given intraperitoneally to mice weekly for 6 consecutive weeks.The mice were then weighed,euthanized,and had their reproductive organs excised.The diabetic(D Group)showed significant impairment of sperm quality and testicular histology compared with the nondiabetic(ND Group).Diameters of the seminiferous lumen in diabetic mice treated with 15 mg kg^(-1) GSH(DGSH15)were decreased compared with the D Group.Sperm motility was also significantly increased in the DGSH15 Group.Improvement in testicular morphology might be an early indication of the protective roles played by the exogenous GSH in protecting sperm quality from effects of untreated type 1 DM or diabetic complications.Further investigation using different doses and different routes of GSH is necessary to confirm this suggestion.