EFFECT OF CLIMATE CHANGE MODEL ON REPRODUCTION: EVALUATION OF PROGRAMMED CELL DEATH AND DNA METHYLATION PROFILE ON MICE OOCYTES AND EMBRYOS

• Grant number: 24/14606-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2024
• End date: October 31, 2025
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: FABÍOLA FREITAS DE PAULA LOPES
• Grantee: Leonardo Shin Matsui Toma
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil

Abstract

Climate change has led to a progressive temperature rise around the world, thus causing a higher incidence of heatwaves. Adverse temperatures are likely to become frequent, putting both the human population and animals at risk of heat stress. Heat stress has deleterious effects on different tissues and systems. In the female reproductive system, heat stress diminishes fertility and pregnancy rates in many species. Due to the impairment in the follicular dynamics, in the hormonal profile, in the reproductive tract and especially in the oocyte and embryo. It is known that both the oocyte and embryo are extremely sensitive to elevated temperatures, reducing its competence of development, as well as altering cellular, molecular and oxidative properties. However, little is known about the effects of heat stress on epigenetic reprogramming during development. Previous studies in our laboratory using whole genome bisulfite sequencing have demonstrated that mice exposed to light heat stress of 35°C during the epigenetic reprogramming window of gametogenesis caused great alterations on the germinative epigenome profile. But with little functional changes, highlighting the plasticity of the epigenome. Moreover, mice exposed to moderate heat stress of 39°C had reduced oocyte competence. Therefore, this study aims to determine the effect of moderate heat stress of 39°C during the events of epigenetic reprogramming that happen during oogenesis and embryogenesis on programmed cell death of oocyte apoptosis and on the DNA methylation profile of embryos.