Effects of extracellular vesicle supplementation during bovine embryo cleavage

• Grant number: 19/04981-2
• Support type: Scholarships in Brazil - Master
• Effective date (Start): April 01, 2019
• Effective date (End): August 31, 2020
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Juliano Coelho da Silveira
• Grantee: Rosane Mazzarella
• Home Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated research grant: 14/22887-0 - Cell-secreted vesicles containing miRNAs modulate epigenetic changes during in vitro culture of bovine gametes and embryos, AP.JP

Abstract

The use of assisted reproduction techniques is an alternative to solve reproductive problems in domestic species and in humans. However, there is concern that the in vitro culture of gametes and embryos can generate epigenetic changes which may lead to increased pre-disposition to cardiac, reproductive or tumor development in adult life. Epigenetic changes are regulated by DNA methylation, post-translational modifications of histones or by microRNAs (miRNA). The miRNAs are non-coding RNAs that regulate gene expression during different processes of tissue differentiation. Recently, vesicles secreted by cells, called exosomes and microvesicles, were found in different body fluids containing bioactive material including miRNAs. These extracellular vesicles (EVs) are considered a new class of cellular communication with possible implications in different physiological processes. However, its role in the acquisition of gametes' competence and in embryonic development is still unknown. The hypothesis that will be tested is that small EVs secreted by oviduct cells are able to alter oocyte fertilization in vitro and the development of bovine embryos produced in vitro. The objective is to evaluate the effects of supplementation of small EVs from oviduct cells in the fertilization of cumulus oocyte complexes (CCOs) and the in vitro embryo development of cattle. For this, EVs will be isolated from oviduct and oviduct conditioned medium and will be characterized. It is expected to determine the role of EVs supplementation during maturation and early embryonic development, which may influence the current in vitro production system. The results obtained in this project will allow the development of protocols more similar to the physiological condition for the in vitro production of embryos, with great impact in the assisted reproduction industry in cattle and in humans.