Interaction of extracellular vesicles from bovine uterine fluid with sperm: impact on sperm fertile potential.

• Grant number: 24/05151-1
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): November 01, 2024
• Effective date (End): May 31, 2025
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Maíra Bianchi Rodrigues Alves
• Grantee: Raissa Braido Rangel
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated research grant: 21/09886-8 - Epigenetic maturation of the oocyte and totipotence: the potential of the oocyte and its relationship with the ovarian follicular niche, AP.SPEC

Abstract

With the advancement of reproductive biotechniques, attention is growing on sperm fertile potential and the need to expand knowledge about sperm characteristics that impact fertility, including molecular features. Sperm are transcriptionally inert and depend on extracellular factors to have their molecular content modulated, a modulation that has already been demonstrated through sperm interaction with extracellular vesicles (EVs) from the epididymal fluid and seminal plasma. In vivo, sperm migrate through the uterine lumen until reaching the oviduct and have interactions with uterine cells, however the modulation of sperm molecular content by EVs released by these cells remains unknown. Furthermore, in vitro, sperm carry out fertilization without this interaction, which could possibly impact sperm molecular content and embryo production rates. Therefore, the objective of this project is to investigate the interaction of sperm with EVs isolated from uterine fluid and the impact on sperm fertile potential in cattle. Spermatozoa obtained from commercial doses of semen from five Nelore bulls will be incubated with EVs isolated from the uterine fluid of high-fertility or infertile cows, prior to in vitro fertilization, to investigate the rates of first cleavage, cleavage and blastocysts. As a control, the spermatozoa will be incubated with the EVs dilution medium and, finally, they will be evaluated for their morphofunctional and molecular characteristics. The data will be analyzed using analysis of variance for sperm evaluations and chi-square test for production rates. The significance level for the tests will be 5%.