Addition effects of IGF-1 or IGF-Long R3 on molecular and cellular aspects during bovine oocytes in vitro maturation

• Grant number: 13/19528-5
• Support type: Scholarships in Brazil - Master
• Effective date (Start): December 01, 2013
• Effective date (End): March 31, 2015
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal researcher: Fernanda da Cruz Landim
• Grantee: Michelle Silva Araujo Volpato
• Home Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Although 80% of in vitro matured oocytes being successfully fertilized, only 30 to 40% blastocysts are produced from oocytes after in vitro maturation (IVM), fertilization and culture of bovine embryos. A major challenge that remains in the field of reproductive biology is the understanding of the global molecular and cellular processes that control oocyte competence. Studies involving the addition of growth-promoting substances to the maturation medium, among which stands out the family of insulin-like growth factors (IGFs), has been highlighted. The IGF-1 and other growth factors are involved in the control of follicular development, oocyte maturation and subsequent embryonic development in several species, including cattle. The recombinant insulin-like growth factor 3 (LongR3-IGF) is an analog of IGF-1 systems widely used in cultivation of follicles and granulosa cells and displays a thousand times lower affinity for IGF binding proteins (IGFBPs) which ensures greater bioavailability. However, no studies have been done yet based on the effects of IGF-Long R3 on in vitro maturation of bovine oocytes. Thus, this study aims to evaluate and compare the meiotic progression using Hoechst-33342 staining, apoptosis by TUNEL assay and gene profile in oocytes (GDF9, BMP15, histona H2A, PDE3, OOSP1) and cumulus cells (FSHR, EGFR, Ampiregulina, Receptor de P4 e COX2) in cumulus-oocyte complexes (CCO) from cattle, after in vitro maturation with IGF-LongR3 hormone or IGF-1. As already shown for IGF-1 is expected that IGF-LongR3 when added to the maturation medium enhances oocyte in vitro maturation, but more efficiently that IGF-1 by its increased bioavailability, thus being able to increase the number of fertilizable oocytes and then, perhaps, the production of viable bovine embryos in vitro. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ARAUJO, M. S.; GUASTALI, M. D.; PAULINI, F.; SILVA, A. N.; TSUNEMI, M. H.; FONTES, P. K.; CASTILHO, A. C. S.; LANDIM-ALVARENGA, F. C.. Molecular and cellular effects of insulin-like growth factor-1 and LongR3-IGF-1 on in vitro maturation of bovine oocytes: comparative study. GROWTH HORMONE & IGF RESEARCH, v. 55, DEC 2020. (13/19528-5)