Digital hypothermia inhibits early lamellar inflammatory signalling in the oligofructose laminitis model.
Authors: van Eps A W, Leise B S, Watts M, Pollitt C C, Belknap J K
Journal: Equine veterinary journal
Summary
# Digital Hypothermia and Early Laminitis Prevention: Understanding the Mechanism Acute laminitis remains a devastating condition in equine practice, and whilst prophylactic digital cryotherapy is known to reduce disease severity, the precise molecular mechanisms underlying this protective effect have been unclear. Van Eps and colleagues used an oligofructose-induced laminitis model in 14 Standardbred horses, comparing cooled and non-cooled forelimbs at two critical timepoints: 24 hours post-administration (before lameness onset) and at lameness onset. Gene expression analysis revealed that cryotherapy significantly suppressed the upregulation of pro-inflammatory mediators in lamellar tissue, including chemokines (CXCL1, CXCL6, CXCL8), cytokines (IL-6, IL-1β), cell adhesion molecules (ICAM-1, E-selectin) and COX-2, whilst paradoxically increasing the protective anti-inflammatory cytokine IL-10 in the early developmental phase. These findings suggest that digital hypothermia works by interrupting the inflammatory cascade at its inception, preventing the cellular recruitment and activation processes that lead to lamellar necrosis and mechanical failure. For practitioners, this research reinforces the evidence base for aggressive ice-water immersion protocols in high-risk laminitis cases and opens potential therapeutic avenues beyond cryotherapy, such as targeted inhibition of specific chemokine or adhesion molecule pathways in future intervention strategies.
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Practical Takeaways
- •Prophylactic cooling of the digit during acute laminitis episodes reduces the inflammatory cascade at the cellular level, providing a mechanistic explanation for why ice therapy improves outcomes in clinical cases.
- •Early application of digital hypothermia (before lameness onset) may be particularly effective at preventing the inflammatory cascade; prompt cooling protocols are therapeutically justified.
- •These molecular findings support cryotherapy as a core intervention in acute laminitis management and suggest it should be initiated early in the disease process for maximum benefit.
Key Findings
- •Digital hypothermia significantly decreased lamellar mRNA concentrations of chemokines (CXCL1, CXCL6, CXCL8), proinflammatory cytokines (IL-6), COX-2, and endothelial adhesion molecules (ICAM-1, E-selectin) compared to non-cooled limbs at lameness onset.
- •In the developmental phase (24h post-oligofructose, prior to lameness), cooled limbs showed decreased mRNA of CXCL1, ICAM-1, IL-1β, CXCL8, and MCP-2, with increased anti-inflammatory IL-10.
- •Cryotherapy blocked early lamellar inflammatory signalling cascade known to contribute to lamellar tissue injury during acute laminitis development.