Equine neutrophil elastase in plasma, laminar tissue, and skin of horses administered black walnut heartwood extract.
Authors: de la Rebière de Pouyade, Riggs, Moore, Franck, Deby-Dupont, Hurley, Serteyn
Journal: Veterinary immunology and immunopathology
Summary
# Editorial Summary: Neutrophil Elastase in Experimentally-Induced Laminitis Black walnut heartwood extract (BWHE) reliably induces laminitis in horses through a systemic inflammatory cascade involving neutrophil activation, and this 2010 study measured neutrophil elastase—a serine protease released from activated neutrophils—across plasma, laminar tissue and skin samples to characterise the inflammatory timeline. Researchers administered BWHE or control water to 28 healthy horses via nasogastric tube, collecting plasma samples at regular intervals (0–12 hours) and harvesting laminar and skin tissue at 1.5, 3, or 12 hours post-administration before euthanasia. BWHE-treated horses showed significantly elevated plasma neutrophil elastase at 6 and 8 hours compared to controls, whilst elastase concentrations in both skin and laminar tissue were markedly higher in the 3 and 12-hour BWHE groups; notably, skin concentrations exceeded those in the lamina, suggesting variable tissue penetration or differential neutrophil infiltration. These findings confirm that laminitis involves a genuinely systemic inflammatory process rather than a purely local tissue event, implicating neutrophil elastase as a potentially destructive agent capable of degrading the basal membrane architecture that anchors the dermal and epidermal laminae. For equine practitioners, this work suggests that therapeutic strategies targeting neutrophil activation or elastase activity during the early developmental phase (particularly within the first 6–12 hours of insult) may represent a viable approach to preventing laminitis progression, though further investigation into inhibitors and their clinical efficacy remains necessary.
Read the full abstract on PubMed
Practical Takeaways
- •Neutrophil elastase emerges as a potential therapeutic target for laminitis treatment, suggesting that anti-neutrophil or anti-elastase interventions may help prevent hoof basal membrane degradation
- •The systemic nature of the inflammatory cascade in laminitis development occurs early (within 6-8 hours), supporting the need for rapid intervention when laminitis is suspected
- •Monitoring systemic markers of neutrophil activation could help identify horses progressing toward clinical laminitis during the developmental phase when intervention may be most effective
Key Findings
- •Plasma neutrophil elastase concentrations were significantly elevated at 6-8 hours post-BWHE administration compared to controls
- •Neutrophil elastase concentrations in skin and laminar tissue were significantly higher in BWHE-treated horses at 3 and 12 hours compared to controls
- •Neutrophil elastase concentrations were significantly higher in skin than in laminar tissue at 12 hours post-BWHE
- •Results confirm neutrophil activation and involvement in the developmental phase of laminitis with systemic inflammatory characteristics