Prospecting the effects of 4-methyl esculetin in the in vitro production of bovine embryos: potential antioxidant effect

• Grant number: 23/17455-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2024
• End date: December 31, 2024
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Marcelo Fábio Gouveia Nogueira
• Grantee: Isabela Batista de Castro Nunes
• Host Institution: Faculdade de Ciências e Letras (FCL-ASSIS). Universidade Estadual Paulista (UNESP). Campus de Assis. Assis , SP, Brazil
• Associated research grant: 21/11747-6 - Remote or presential: the importance of communication in the reproductive processes, AP.TEM

Abstract

In the bovine species, in vitro embryo production (IVP) is a biotechnology in growing demand in recent years, with constant search for the development of technical innovations or inputs. The ultimate goal is to improve the quality of the embryo (blastocyst) and, consequently, its ability to tolerate cryopreservation and sustain full term pregnancy. However, one of the inherent problems of IVP is oxidative stress, by generating reactive oxygen species (ROS) from exposure to external elements such as ambient light and atmospheric air. Several strategies to mitigate oxidative stress have been tested, but so far, nothing has been explored about the antioxidant capacity of coumarin derivatives in IVP in cattle. 4-Methylculetin is a hydroxyumarin that has already demonstrated an antioxidant effect in studies with non-embryon cells. This study aims to use 4-methylculetin (4-ME) during the stages of maturation (IVM) and in vitro culture (IVC) of IVP. In Experiment 1, concentrations of 0 (control), 50, 100 and 200¼M of 4-ME in IVM (4 to 5 replicats) and IVC (4 to 5 replicats) will be used. To evaluate a possible embryotoxic effect, blastocyst (D7-8) and hatching (D9) rates will be compared with the control group. After this and if there is any promising evidence with the use of 4-ME (Experiment 1), the highest concentration that does not present evidence of toxicity (when used in both IVM and IVC) will be chosen for Experiment 2. In this, the abundance of ROS at the end of IVM will be measured (oocytes; 3 replicates) and IVC (blastocysts in D7; 3 replicates). The statistical analysis will be performed with parametric tests (if the data are normal) for four groups (ANOVA, Experiment 1) and for two groups (Student's t test, Experiment 2) and significance level of 5%.