Laminar inflammatory events in lean and obese ponies subjected to high carbohydrate feeding: Implications for pasture-associated laminitis.
Equine Vet J
; 47(4): 489-93, 2015 Jul.
Article
in En
| MEDLINE
| ID: mdl-24963607
ABSTRACT
REASONS FOR PERFORMING STUDY Acute, massive enteral carbohydrate overload is associated with laminar inflammation in equids; it is unclear if the same is true for a more prolonged period of moderate dietary carbohydrate intake. OBJECTIVES:
To characterise laminar inflammation in ponies exposed to a dietary carbohydrate challenge meant to mimic acute pasture exposure. STUDYDESIGN:
In vivo experiment.METHODS:
Mixed-breed ponies (n = 22) received a diet of hay chop (nonstructural carbohydrate [NSC] â¼7% on a dry matter [DM] basis) for 4 weeks prior to initiation of the experimental feeding protocol. Following dietary acclimation, ponies were stratified into either Lean (n = 11, body condition score [BCS] ≤4) or Obese (n = 11, BCS ≥7) groups and each group further stratified to either remain on the control, low NSC diet (n = 5 each for Obese and Lean) or receive a high NSC diet (hay chop supplemented with sweet feed and oligofructose, total diet â¼42% NSC; n = 6 each for Obese and Lean) for a period of 7 days. Laminar samples were collected following euthanasia and sections stained immunohistochemically for CD163, MAC387/calprotectin and cyclo-oxygenase-2 (COX-2) using commercially available antibodies. The number of CD163 (+) and MAC387(+) cells was quantified for each section; the distribution of COX-2 expression was qualitatively assessed. Laminar mRNA concentrations of several proinflammatory molecules (interleukin-1ß [IL-1ß], IL-6, tumour necrosis factor-α [TNFα], IL-8, IL-10, monocyte chemoattractant protein-1 [MCP-1], MCP-2), inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1), E-selectin, plasminogen activator inhibitor-1 (PAI-1) and COX-2 were evaluated using real-time quantitative polymerase chain reaction (qPCR).RESULTS:
High carbohydrate feeding resulted in no increase in laminar proinflammatory cytokine expression; laminar COX-2 expression was increased by high carbohydrate feeding. No laminar leucocyte infiltration was observed in response to high carbohydrate feeding.CONCLUSIONS:
These results suggest that the marked laminar inflammation observed in models of sepsis-associated laminitis may not play a central role in the pathophysiology of pasture-associated laminitis.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Carbohydrates
/
Foot Diseases
/
Horse Diseases
/
Inflammation
/
Obesity
Type of study:
Prognostic_studies
/
Risk_factors_studies
Limits:
Animals
/
Female
/
Humans
/
Male
Language:
En
Journal:
Equine Vet J
Year:
2015
Document type:
Article
Affiliation country:
United States