Serum proteomic analysis in equine obstructive colic: A prospective observational study

The aim of the study was to identify proteomic signatures from the serum of horses affected by simple obstructive intestinal colic to characterize the pathological process and to assess potential biomarkers for early diagnosis. Seven horses with obstructive colic received venous blood samples for determination of standard hematobiochemical, inflammatory, and lipid profiles at the time of initial clinical examination and after conservative therapy upon recovery. Proteomic profiling was also performed on all samples by means of a within-group analysis (sick horses at discharge vs. sick horses at admission). A validation of expression levels was performed by the Multiple Reaction Monitoring approach. In the within-group comparison, 70 proteins showed a significant difference; The proteins involved in the immune response (C2, FC 2.41; CFB, FC 3.41; HPX, FC 7.36; LTF, FC 0.55; PSMA7, FC-0.55), blood coagulation (VWF, FC 0.54; F13A1, FC-0.54; F13B, FC-0.57; PRDX2, FC-0.41; FBLN1, FC-0.62; KNG1, FC-3.86) and lipid homeostasis (APOA4, FC 0.66; APOA5, FC 0.13; APOE, FC-0.56; LCAT FC-0.58) have changed. The study suggested the coexistence of inflammatory status, the presence of intestinal bacteria that may have triggered the immune response, and hyperlipidemia in horses with obstructive colic.