Proteomics of endometrial fluid after dexamethasone treatment in mares susceptible to endometritis

Abstract

Corticotherapy is a common treatment in mares susceptible to endometritis. Isoflupredone improves pregnancy rates and affects the protein profile of endometrial fluid in comparison to untreated mares. Dexamethasone decreases postbreeding fluid accumulation and uterine edema; however, its effects on the protein profile of the endometrial fluid have not yet been studied. The aim of the present study was to verify the effect of dexamethasone on the protein profile of endometrial fluid, in the presence or absence of infection, from mares susceptible to persistent postbreeding endometritis. Nine susceptible mares aged between 7 and 18 years were used. After checking for signs of estrus, mares were subjected to four treatments: C: mares received no treatment and served as control; D: mares received 40-mg dexamethasone at breeding, with collection of samples after 6 hours; I-6 and I-24: intrauterine infusion of 1 × 109Streptococcus zooepidemicus/mL and samples collected after 6 and 24 hours; I/D-6 and I/D-24: intrauterine infusion of 1 × 109S zooepidemicus/mL and 40-mg dexamethasone, collecting the sample after 6 and 24 hours. All mares were subjected to all treatments. Samples were collected and subjected to two-dimensional electrophoresis and mass spectrometry for the identification of relevant protein spots. Corticotherapy altered the protein profile of the endometrial fluid of susceptible mares, characterized by an increase and/or decrease in the optical density of inflammatory acute-phase proteins. We conclude that the use of dexamethasone in mares with and without infection alters the protein profile of endometrial fluid of susceptible mares.