A saliva test for equine ulcers?

Changes in the saliva proteome analysed by gel-proteomics in horses diagnosed with equine gastric ulcer syndrome (EGUS) at diagnosis and after successful treatment

Res Vet Sci. 2023 Dec 15:167:105112. doi: 10.1016/j.rvsc.2023.105112. Online ahead of print.
Authors
María José López-Martínez 1 , Elsa Lamy 2 , José Joaquín Cerón 3 , Ignacio Ayala 4 , María Dolores Contreras-Aguilar 5 , Ida-Marie Holm Henriksen 6 , Alberto Muñoz-Prieto 7 , Sanni Hansen 8
Affiliations

1 Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Regional Campus of International Excellence ‘Campus Mare Nostrum’, University of Murcia, Campus de Espinardo s/n, 30100 Murcia, Spain. Electronic address: mariajose.lopez28@um.es.
2 MED – Mediterranean Institute for Agriculture, Environment and Development & CHANGE – Global Change and Sustainability Institute, University of Évora, Évora, Portugal. Electronic address: ecsl@uevora.pt.
3 Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Regional Campus of International Excellence ‘Campus Mare Nostrum’, University of Murcia, Campus de Espinardo s/n, 30100 Murcia, Spain. Electronic address: jjceron@um.es.
4 Department of Animal Medicine & Surgery, Veterinary School, Regional Campus of International Excellence Mare Nostrum, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain. Electronic address: iayape@um.es.
5 Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Regional Campus of International Excellence ‘Campus Mare Nostrum’, University of Murcia, Campus de Espinardo s/n, 30100 Murcia, Spain. Electronic address: mariadolores.contreras@um.es.
6 Department of Veterinary Clinical Sciences, Section Medicine and Surgery, University of Copenhagen, Agrovej 8, 2630 Taastrup, Denmark. Electronic address: ida-marie.boll@sund.ku.dk.
7 Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Regional Campus of International Excellence ‘Campus Mare Nostrum’, University of Murcia, Campus de Espinardo s/n, 30100 Murcia, Spain. Electronic address: alberto.munoz@um.es.
8 Department of Veterinary Clinical Sciences, Section Medicine and Surgery, University of Copenhagen, Agrovej 8, 2630 Taastrup, Denmark. Electronic address: sannih@sund.ku.dk.

PMID: 38176208
DOI: 10.1016/j.rvsc.2023.105112

Abstract

Equine gastric ulcer syndrome (EGUS) is currently one of the more frequent diseases in horses. We aimed to identify changes in the salivary proteome in horses with EGUS at diagnosis and after successful treatment by using gel proteomics. Saliva samples were collected from nine horses with EGUS before and after treatment and nine matched healthy controls. SDS-PAGE (1DE) and two-dimensional gel electrophoresis (2DE) were performed, and significantly different protein bands and spots were identified by mass spectrometry. Horses with EGUS had increases in proteins such as adenosine deaminase (ADA), triosephosphate isomerase, keratins and immuno-globulin heavy constant mu and decreases in carbonic anhydrase (CA), albumin and prolactin-induced protein. These changes would indicate various physiopathological mechanisms involved in this disease, such as the activation of the immune system, decreased stomach defence mechanisms and inflammation. The treated horses presented lower expression levels of thioredoxin (TRX) after a successful treatment, in proteomics analysis and also measured with a commercially available ELISA kit. Overall, horses with EGUS have protein changes in their saliva when measured with gel proteomics compared with healthy horses, and they also showed changes after successful treatment. These proteins could be potential biomarkers for detection and monitoring treatment response in EGUS.

Keywords: Biomarkers; EGUS; Horses; Salivary proteome.