Influence of Insulin-Like Growth Factor-I on Maturation and Fertilization Rate of Immature Oocyte and Embryo Development in NMRI Mouse with TCM199 and α-MEM Medium

Abstract

Introduction: In vitro maturation (IVM) of oocytes and subsequent, in vitro fertilization (IVF) for the generation of embryos in the laboratory has important values. Growth factors are a component of a complex system of autocrine and paracrine factors that have a regulatory role in ovarian function and affect oocyte maturation. Therefore, the aim of this study is to evaluate the effect of IGF-I on IVM and IVF of mice oocytes during culture with α-MEM and TCM199 medium. Materials and Methods: Cumulus oocyte complexes (COCs) and denuded oocyte were obtained from 4-6 week old NMRI mice and underwent in vitro maturation and in vitro fertilization in presence or absence of IGF-I with α-MEM and TCM199. Result: Maturation rate (79.6%), fertilization rate (87.2%), two cells development rate (79.5%) and blastocyst rate(43.2%) was higher in COCs cultured in α-MEM with IGF-I, while lower maturation rate (50.6%) fertilization rate (61%), two cells development rate (48.8%) and blastocyst rate(14.6%) were seen in cultured denuded oocytes (DOs) in TCM199 without growth factor. As well as, maturation fertilization, two cells development and blastocyst rates in COCs were higher than DOs. Conclusion: Our findings have shown that IGF-I is involved in the oocyte biology and improve the oocyte maturation, fertilization and embryo development to blastocyst competence in vitro. In addition, it has also shown that cumulus cells are vital for oocyte development when IGF-1 added to the mediums.

Keywords

• embryo development
• insulin-like growth factor-i
• maturation
• oocyte