Effect of platelet-rich plasma on endometrial reaction and uterine microbiota in mares susceptible to endometritis and in vitro antimicrobial effect on bacteria responsible for endometritis in mares

• Grant number: 21/05152-0
• Support type: Regular Research Grants
• Duration: November 01, 2021 - October 31, 2023
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal researcher: Marco Antonio Alvarenga
• Grantee: Marco Antonio Alvarenga
• Home Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Assoc. researchers: Igor Frederico Canisso ; Lorenzo Garrido Teixeira Martini Segabinazzi

Abstract

Post-breeding endometritis is a physiological process after exposure to semen, which must be resolved within 48 hours. This inflammation is necessary to eliminate excess semen, debris, and microorganisms from the uterus. However, endometritis can become persistent if this inflammation is not resolved or as a result of a microbial infection. In healthy and resistant mares, this post-breeding inflammation is eliminated within 48 hours, however mares unable to eliminate this inflammation within 96 h are considered susceptible to persistent breeding-induced endometritis (PBIE). Endometritis is the major cause of subfertility in mares, and is the third most common disease in horses. Infectious endometritis is caused mainly by microorganisms such as Staphylococcus aureus, Streptococcus equi subs. zooepidemicus, Escherichia coli, Pseudomonas aeruginosa; Klebsiella pneumoniae, Candida spp. and Aspergillus spp. Susceptible mares have low reproductive efficiency, accumulation of uterine fluid, and an exacerbated number of neutrophils in the uterine lumen after covering. Several studies have shown promising results in the treatment of inflammatory and infectious conditions using platelet-rich plasma (PRP), as well as improving reproductive efficiency in women, cows and mares. However, the mechanism by which PRP acts by modulating the inflammatory response in the uterus has not been elucidated. Recent studies have shown that the mammalian uterus is occupied by a resident microbiota that confers resistance against infectious agents. Thus, the present proposal has been justified to evaluate the anti-inflammatory, antimicrobial effects, and the potential modulating role of PRP in the uterine microbiota of mares susceptible to EPPC. We aim to understand the mechanism (s) of action of PRP in the uterus of mares through the use of modern tools of genomics and bioinformatics; in addition, the present study will use in vitro techniques to evaluate the antimicrobial properties of PRP against pathogens commonly causing endometritis in mares. Two studies are proposed, one in vivo study where the population microbiota and genetic sequencing of the endometrium of mares susceptible to EPPC treated with PRP after being challenged with sperm will be evaluated; and a second in vitro study evaluating the effect of PRP against microorganisms (Streptococcus equi zooepidemicus; Staphylococcus aureus; Klebsiella pneumoniae; Pseudomonas aeruginosa, Escherichia coli) isolated from the uterus of mares with clinical endometritis. (AU)