Post-doc student College of Veterinary Medicine, The Ohio State University Columbus, Ohio, United States
Abstract:
Background: Hypovitaminosis D is common in critically ill patients, including foals. In addition to calcium and phosphorus homeostasis, vitamin D has antibacterial properties through antimicrobial peptides (β-defensin-1 and cathelicidin). These peptides have not been evaluated in equine patients but could play a role in disease progression.
Objectives: To measure serum vitamin D metabolites (25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] and determine their association with β-defensin-1 and cathelicidin concentrations, disease severity and outcome in hospitalized foals.
Methods: Prospective, multicenter study. 60 foals < 72 hours (hospitalized = 41; healthy = 19) were included. Blood samples were collected over 72 h to measure serum 25(OH)D, 1,25(OH)2D, β-defensin-1 and cathelicidin concentrations. Data were analyzed by non-parametric methods and univariate logistic regression.
Results: On admission, serum 25(OH)D and 1,25(OH)2D concentrations were lower in hospitalized compared to healthy foals (P < 0.05). Serum β-defensin-1 and cathelicidin concentrations were lower in all time points in hospitalized than healthy foals (P < 0.05). There was a positive correlation between serum β-defensin-1 and 25(OH)D in hospitalized foals (r = 0.72; P < 0.05). Non-surviving foals had the lowest serum 25(OH)D concentrations (P < 0.05). Hospitalized foals with serum 25(OH)D < 6.1 ng/mL were more likely to die (OR = 5.1; P < 0.05).
Conclusions: Decreased antimicrobial peptides in the presence of hypovitaminosis D and their association with disease severity indicates that vitamin D directly and through its regulated genes is protective against illness in newborn foals.
