Histopathology of insulin-induced laminitis in ponies.
Abstract: Ponies with laminitis associated with insulin resistance and hyperinsulinaemia lack systemic and/or intestinal inflammatory signs, suggesting a different pathogenesis potentially reflected in differing histopathology. Objective: To describe the histological appearance and quantify morphological changes in primary and secondary epidermal lamellae (PEL and SEL) of laminitis lesions from ponies with insulin-induced laminitis. Methods: Equine hoof lamellar tissue was obtained from 4 control ponies and 5 ponies with laminitis induced following infusion of insulin (1036 ± 55 µU/ml) while maintaining euglycaemia for 55.4 ± 5.5 h. Sections from all 4 hooves were stained and examined by a veterinary pathologist. Measurements of lamellar length (PEL and SEL) were made in mid-dorsal sections of the right forefeet by 2 blinded observers. Immunolabelling for calprotectin was performed using a monoclonal antibody. Results: No lesions were detected in normal ponies. Lesions detected in ponies with laminitis were variable in severity between ponies. Within ponies, SEL lesions were more severe along the axial region of PEL. Lesions included swelling, disorganisation and abnormal keratinisation of epidermal cells, increased mitotic activity and apoptosis. Separation of basement membranes was minimal. Immunostaining revealed inflammatory cells within the lamellar dermis. SEL were significantly elongated in laminitic hooves relative to controls, with the greatest elongation in those attached to abaxial and middle regions of PEL. Conclusions: Laminitis induced by prolonged infusion of insulin lacked widespread basement membrane disintegration, and increases in epidermal cellular proliferation at axial aspects were marked for this acute stage of disease. Conclusions: Defining equine laminitis entirely in terms of separation of the basement membrane may not be appropriate for laminitis associated with hyperinsulinaemia.
© 2010 EVJ Ltd.
Publication Date: 2010-11-03 PubMed ID: 21039799DOI: 10.1111/j.2042-3306.2010.00111.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research article focuses on studying the changes in the tissue structure of the hooves in ponies affected by insulin-induced laminitis, a hoof-related disease. Essentially, the study examines the specific tissue deformities caused by the disease in an attempt to better understand its pathogenesis.
Research Methodology
- The researchers carried out their study using tissue samples from the hooves (specifically the lamellae) of 4 healthy ponies and 5 ponies suffering from insulin-induced laminitis.
- Laminitis in the test group was induced by infusing insulin while maintaining normal blood glucose levels.
- A veterinary pathologist then studied and examined tissue sections from all four hooves of each pony.
- The length of the primary and secondary epidermal lamellae (PEL and SEL)—the layers of tissue within the hoof—were measured by two observers who did not know which samples belonged to the healthy or diseased ponies.
- Immunolabelling was carried out for calprotectin, a protein complex associated with inflammation and cell proliferation, to identify the presence of inflammatory cells.
Research Findings
- The study found that there were no lesions or abnormalities in the hoof tissues of the healthy ponies.
- In the ponies affected by laminitis, the changes differed in severity and were more pronounced along the axial region of the primary epidermal lamellae.
- The abnormalities observed included swelling, tissue disorganization, and abnormal keratinization of epidermal cells. The researchers also found increased cell division and programmed cell death or apoptosis.
- The researchers also found that the separation of the basement membrane, the layer that secures the epidermal cells to the hoof structure, was minimal.
- Immunolabelling showed the presence of inflammatory cells within the layers of the hoof tissue.
- The length of the secondary epidermal lamellae was significantly increased in the hooves affected by laminitis when compared to the control group.
Research Conclusions
- The research highlighted that traditional understanding of laminitis, involving separation of basement membrane, may not completely apply to cases linked with high insulin levels.
- In these cases, the disease did not involve extensive separation of the basement membrane but was marked by increased cell proliferation in certain areas of the hoof.
Cite This Article
APA
Asplin KE, Patterson-Kane JC, Sillence MN, Pollitt CC, Mc Gowan CM.
(2010).
Histopathology of insulin-induced laminitis in ponies.
Equine Vet J, 42(8), 700-706.
https://doi.org/10.1111/j.2042-3306.2010.00111.x Publication
Researcher Affiliations
- School of Veterinary Science, The University of Queensland, Australia.
MeSH Terms
- Animals
- Foot Diseases / chemically induced
- Foot Diseases / metabolism
- Foot Diseases / pathology
- Foot Diseases / veterinary
- Hoof and Claw / pathology
- Horse Diseases / chemically induced
- Horse Diseases / metabolism
- Horse Diseases / pathology
- Horses
- Insulin / administration & dosage
- Insulin / toxicity
- Leukocyte L1 Antigen Complex / metabolism
Citations
This article has been cited 4 times.- Malacarne BD, Martins RR, Paz CFR, Alves JVA, Dias LA, Cavalcante MA, Santos AM, Silva AGM, Leise BS, Carvalho AM, Faleiros RR. Histological comparison of the lamellar tissue of Iberian origin breed horses created in semi-feral conditions or in an intensive system. PLoS One 2023;18(6):e0286536.
- Bäßler SC, Kenéz Á, Scheu T, Koch C, Meyer U, Dänicke S, Huber K. Association between alterations in plasma metabolome profiles and laminitis in intensively finished Holstein bulls in a randomized controlled study. Sci Rep 2021 Jun 17;11(1):12735.
- Baskerville CL, Chockalingham S, Harris PA, Bailey SR. The effect of insulin on equine lamellar basal epithelial cells mediated by the insulin-like growth factor-1 receptor. PeerJ 2018;6:e5945.
- Dunbar LK, Mielnicki KA, Dembek KA, Toribio RE, Burns TA. Evaluation of Four Diagnostic Tests for Insulin Dysregulation in Adult Light-Breed Horses. J Vet Intern Med 2016 May;30(3):885-91.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
