Evaluation of tear film proteinases in horses with ulcerative keratitis.
Abstract: Ulcerative keratitis is a common and potentially blinding ocular disease of horses, capable of progressing to corneal perforation in as little as 24 h. This rapid stromal degeneration is mediated in part by exogenous and endogenous proteinases. We measured and compared the concentrations of two matrix metalloproteinases (MMP-2 and MMP-9) and a serine proteinase (neutrophil elastase) present in the precorneal tear film of normal horses and horses with rapidly progressing ulcerative keratitis. Precorneal tear film samples were collected from 23 ulcerated and 21 unaffected eyes of 23 horses with unilateral ulcerative keratitis, and from 33 normal eyes of 17 control horses. MMP-2, MMP-9, and neutrophil elastase were identified by casein and gelatin zymography and quantified by computerized image analysis. Median MMP-9 levels were significantly higher in the precorneal tear film of young control horses vs. older control horses (P = 0.005). Median MMP-2, MMP-9, and neutrophil elastase levels were significantly higher in the precorneal tear film of ulcerated eyes when compared to age-matched normal controls (P = 0.004, P = 0.001, and P = 0.012, respectively). Median MMP-2 levels were also significantly higher in the precorneal tear film of contralateral eyes of affected horses when compared to age-matched normal controls (P = 0.004). No significant differences in median proteinase levels were detected between 'sterile' ulcers and those from which bacteria or mixed infections (bacteria and fungi) were isolated. However, median MMP-2 and neutrophil elastase levels were significantly higher in the precorneal tear film of eyes with 'sterile' ulcers when compared with ulcerated eyes from which fungi were isolated (P < 0.05). The results of this study support the use of topical antiproteinase therapy which targets both MMPs and serine proteinases in progressive equine ulcerative keratitis.
Publication Date: 2001-06-09 PubMed ID: 11397292DOI: 10.1046/j.1463-5224.2000.00093.xGoogle Scholar: Lookup
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- Journal Article
Summary
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The research investigates the role of certain proteins in the tear film of horses suffering from ulcerative keratitis, an eye disease that could lead to blindness. The study concludes that topical treatment targeting these specific proteins could be useful in treating this condition.
About the Research
- The study aimed to understand the role of certain proteins, particularly two matrix metalloproteinases (MMP-2 and MMP-9) and a serine proteinase (neutrophil elastase), in contributing to the rapid degeneration of the cornea in horses suffering from ulcerative keratitis. This is a potentially vision-threatening disease in horses that can cause the cornea to perforate within 24 hours.
- Precorneal tear film samples of both normal horses and those with ulcerative keratitis were collected and analyzed. The samples comprised 33 normal eyes from 17 healthy horses and 44 eyes from 23 horses with the disease (23 affected and 21 unaffected).
- The concentrations of MMP-2, MMP-9, and neutrophil elastase in these tear film samples were measured and compared using casein and gelatin zymography, combined with a digital image analysis.
Findings
- First, it was found that the level of MMP-9 was significantly higher in the tear film of young healthy horses compared to the older ones.
- Significantly higher levels of MMP-2, MMP-9, and neutrophil elastase were found in the tear film of ulcerated eyes when compared to the eyes of age-matched healthy horses.
- In addition, levels of MMP-2 were higher in the unaffected eye of horses with one affected eye, when compared to the eyes of age-matched healthy horses.
- No significant difference in proteinase levels was observed between sterile ulcers and those contaminated with bacteria or mixed infections. However, significantly higher levels of MMP-2 and neutrophil elastase were present in the tear film of eyes with sterile ulcers compared to those with fungal infections.
Conclusion
- The results suggest that the elevated levels of these proteins contribute to the rapid progress of ulcerative keratitis in horses.
- The study, therefore, advocates for the use of topical antiproteinase treatment targeting both MMPs and serine proteinases to manage progressive equine ulcerative keratitis.
Cite This Article
APA
Strubbe DT, Brooks DE, Schultz GS, Willis-Goulet H, Gelatt KN, Andrew SE, Kallberg ME, MacKay EO, Collante WR.
(2001).
Evaluation of tear film proteinases in horses with ulcerative keratitis.
Vet Ophthalmol, 3(2-3), 111-119.
https://doi.org/10.1046/j.1463-5224.2000.00093.x Publication
Researcher Affiliations
- Departments of Small and Large Animal Sciences, University of Florida College of Veterinary Medicine, PO Box 100126, Gainesville, Florida 32610-0126, USA.
Citations
This article has been cited 6 times.- Stolle LM, Oltmanns H, Meißner J, Heun F, Schieder AK, Wolff HT, Ohnesorge B, Busse C. Polyhexanide, Povidone-Iodine, and Hypochlorous Acid Show High In Vitro Antimicrobial Efficacy Against Pathogens Commonly Associated With Equine Infectious Keratitis. Vet Ophthalmol 2026 Jan;29(1):e70141.
- Farghali HA, AbdElKader NA, AbuBakr HO, Ramadan ES, Khattab MS, Salem NY, Emam IA. Corneal Ulcer in Dogs and Cats: Novel Clinical Application of Regenerative Therapy Using Subconjunctival Injection of Autologous Platelet-Rich Plasma. Front Vet Sci 2021;8:641265.
- Barton AK, Richter IG, Ahrens T, Merle R, Alalwani A, Lilge S, Purschke K, Barnewitz D, Gehlen H. MMP-9 Concentration in Peritoneal Fluid Is a Valuable Biomarker Associated with Endotoxemia in Equine Colic. Mediators Inflamm 2021;2021:9501478.
- Guyonnet A, Bourguet A, Donzel E, Bataille G, Pascal Q, Laloy E, Boulouis HJ, Milleman Y, Chahory S. Bilateral bullous keratopathy secondary to melting keratitis in a Suri alpaca (Vicugna pacos). Clin Case Rep 2018 Apr;6(4):626-630.
- Laurie DE, Splan RK, Green K, Still KM, McKown RL, Laurie GW. Detection of prosecretory mitogen lacritin in nonprimate tears primarily as a C-terminal-like fragment. Invest Ophthalmol Vis Sci 2012 Sep 12;53(10):6130-6.
- Mathalone N, Marmor S, Rahat MA, Lahat N, Oron Y, Geyer O. MMP expression in leaking filtering blebs and tears after glaucoma filtering surgery. Graefes Arch Clin Exp Ophthalmol 2011 Jul;249(7):1047-55.
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