Effect of Specific Nutrients on Ovulation, Oocytes Development, Gene Expression and Coupling Success in Mice

Introduction: The roles of genetic, epigenetic, metabolic and other environmental factors such as nutrition and stress, are becoming evident for a successful and healthy pregnancy. This raises the possibility and question, if and how, we improve the probability of pregnancy and of a healthy fetus? The present study examined the role of metabolic, antioxidant and minerals and the results suggest that these factors may positively influence the oocyte quality and the pregnancy rate. Methods: CD1 female mice aged 15 and 5 weeks were divided into four groups of ten each and treated by intragastric gavage daily for 3 weeks. G1: Vehicle; G2: Carnitines (L-carnitine 0.4 mg and acetyl-L-carnitine 0.12 mg/mouse); G3: Microelements (Zinc 4 ng, Copper 0.8 ng, Iron 7 ng/mouse); G4: G3+G2. At the end of the treatment period superovulation was induced and oocytes were collected to assess their quantity and quality. Further, in vitro fertilization (IVF) experiments were performed to assess the preimplantation embryo development. The birth success rate was also analyzed in old and young female. The mice were in vivo fertilized. qRT-PCR were performed to analyze a possible modulation in key genes of the reproductive process. Results: The number of oocytes was significantly higher in groups 2 and 4 compared to the control group. The oocyte number in group 3 was not affected. The level of degraded oocytes was 29.1% and 19.3% (group 2 and 4) versus 34.3% (control). Concomitantly, the numbers of embryos arriving to successful birth were also increased in G4, both in the old and young group of mice. Preliminary analysis of genes affected evidenced that AMH was up regulated in the ovary and KITL in the uterus in group 2. Conclusion: Results showed that L-carnitine, acetyl-L-carnitine and micronutrients were able to improve both oocytes quality and success rate of pregnancy. Further studies are planned to further examine ways to improve pregnancy and fetal health.