Assessment of oxidative stress during pregnancy in healthy mares

• Grant number: 24/03083-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2024
• End date: December 31, 2024
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Breno Fernando Martins de Almeida
• Grantee: Anna Flávia Valeri
• Host Institution: Centro Universitário Faculdades Integradas de Ourinhos. Fundação Educacional Miguel Mofarrej. Ourinhos , SP, Brazil

Abstract

Oxidative stress is the imbalance between oxidizing compounds and antioxidants, inwhich excessive release of free radicals can react with almost allbiological molecules, including nucleic acids, proteins, carbohydrates and lipids,causing oxidative damage to cells and tissues. During pregnancy, the contributionhigh oxygen levels can increase the production of reactive oxygen species andfailure of antioxidant protection mechanisms, leading to oxidative damage. They existmany descriptions of the role of oxidative stress in pregnancy in humans andits direct relationship with fetal and neonatal changes, with such studies being scarce inequines. In this context, the present project aims to test the hypothesis thatthat oxidative stress occurs during pregnancy in healthy mares. ForAs such, 25 recipient mares will have blood samples obtained prior to transfer andmonthly until the moment of delivery, all clinically healthy and without changesin screening tests (blood count and biochemical profile with albumin, total protein,globulin, creatinine, urea, aspartate aminotransferase and gamma glutamyltransferase).Hematological analyzes will be performed in an automated cell counterveterinary tests with differential leukocyte count and morphological analyzes inblood smear using optical microscopy. Biochemical determinationswill be carried out in an automated photocolorimeter using a set of reagentscommercial products and following the manufacturers' recommendations. Oxidative stress will bedetermined in an automated photocolorimeter by evaluating the capacitytotal antioxidant (CAT) by four methods: equivalent to trolox by inhibition ofreduction of the ABTS cation (CAT-ABTS), inhibition of the reduction of the associated ABTS cationto peroxidase (CAT-ABTS+HRP), ferric (CAT-FRAP) and cupric (CAT CUPRAC) reduction; in addition to determining the total oxidizing capacity (TOC), peroxidationlipid by substances reactive to thiobarbituric acid (TBARS) and antioxidantsuric acid and albumin. The variables will be tested for normality asdifferences between moments will be verified by ANOVA tests with measurementsrepeated with Tukey or Friedmann post-test with Dunn's post-test, withconsidered significant when p<0.05.