Equine neutrophil elastase in plasma, laminar tissue, and skin of horses administered black walnut heartwood extract.

This study conducted on horses found that the administration of black walnut heartwood extract (BWHE) increased concentrations of neutrophil elastase, a protein secreted by a type of white blood cell, in the blood, skin, and laminar tissues. This increase, caused by inflammation, further supports the theory that the white blood cells, called neutrophils, play a significant role in the development of laminitis, an inflammatory condition of the hoof.

Objective and Methodology

• The researchers aimed to measure the concentrations of neutrophil elastase in the blood, skin, and laminar tissues (layers in the horse’s hoof) after the administration of BWHE, which has been known to induce laminitis.
• Healthy horses of varying ages were divided into four groups, three received BWHE via a nasogastric (through the nose and into the stomach) tube, while the control group was given an equal volume of water.
• The horses in the experimental groups were euthanized at different intervals after the administration of BWHE to examine the impact over time. Control horses were euthanized 12 hours after the administration of water.
• Blood samples were collected from the horses at several points after treatment and laminar tissue and skin samples were collected upon euthanasia.
• A statistical significance level of p<0.05 was set, implying that only results with a probability of 5% or less were considered statistically significant.

Findings

• Blood levels of neutrophil elastase in the BWHE group were significantly higher at specific time intervals compared to the control group.
• Neutrophil elastase concentrations were also significantly elevated in skin and laminar tissue for the BWHE administered horses at 3 and 12 hours after exposure to BWHE, again compared to the control group.
• The study found higher neutrophil elastase concentrations in the skin than in the laminar tissue of horses 12 hours post BWHE intake, suggesting a systemic impact of the inflammatory process.

Implications

• The findings of the study confirm the contribution of neutrophils in the early stages of laminitis and the overall systemic nature of this inflammatory condition.
• As neutrophil elastase may contribute to the deterioration of the hoof’s basal membrane, it may be a possible target for developing new treatments for laminitis.