P-25: Study of the Effect of Experimental Diabetes Induced by STZ on In vitro Fertilization and Preimplantation Embryo Development Rate in Male Mouse Model

Background: Diabetes is a metabolic disease caused by a deficiency in the pancreatic secretion of insulin and/or by the inability of tissues to efficiently respond to insulin, events that cause hyperglycemia and affect all organs.Tissue alterations caused by diabetes affect different organic systems , including the male reproductive system. Reproductive dysfunction is one of the common secondary effects of diabetes. The aim of the present study was to consider the fertility index, in vitro fertilization, and embryo developmental rate. Materials and Methods: In this experiment two groups of male mice were either received intraperitoneally 50 mg/kg bw daily for 5 days of STZ to induce type 1 diabetes or solvent as control sham.Diabetes was confirmed 5-7 days after the last injection of STZ by the determination of glycemia.Following 45 days of last injection each group of animals was sacrificed by cervical dislocation.Cauda epididymis were removed surgically and placed in 1 ml HTF + BSA 4mg/ml medium (preequilibirated) and incubated for 30 minute in Co2 incubator(5% Co2, 37°C) to allow the spermatozoa to swim out .For each male mouse, 3 superovulated mouse oocytes were collected and fertilized by fresh sperms of each groups.The rate of fertilization, two cell embryos, arrested embryos,blastocytes and embryos quality examined in period of 120 hours.The data were later compared and statistically analyzed by 2 proportion test (p<0.05). Results: The results obtained from this study revealed that fertilization rates were significantly lower in the STZ-injected group as compared to the normal group. Also the fertilized, embryo development rates to the blastocyst stage were lower in diabetic models as compared to controls.The rate of arrested embryos including lysis and degenerated blastomers and cytoplasmic vesicles has been increased significantly in experimental diabetic group (p<0.05). Conclusion: Althogh diabetes is one of the major factors of organic impotence, in this study the results showed that the fertilization rate of spermatozoa and preimplantation embryo development in diabetic mouse were decreased significantly. Present results highly support the idea that diabetes induced testicular injury with adverse effect on sperm production, sperm DNA integration and maturation of nucleous.