Revealing the Therapeutic Potential of Muscle-Derived Mesenchymal Stem/Stroma Cells: An In Vitro Model for Equine Laminitis based on Activated Neutrophils, Anoxia-Reoxygenation and Myeloperoxidase

Equine laminitis is a debilitating condition characterized by the breakdown of the dermal–epidermal junction, resulting in severe lameness and pain, often requiring euthanasia. This study aimed to establish an in vitro model of laminitis using a continuous keratinocyte cell line exposed to anoxia-reoxygenation and activated neutrophil supernatant. A significant decrease in keratinocytes metabolism was noted during the reoxygenation period, indicative of cellular stress. Adding muscle-derived mesenchymal stem/stroma cells during reoxygenation demonstrated a protective effect, restoring keratinocytes metabolic activity. Moreover, incubation of keratinocytes with activated neutrophil supernatant or myeloperoxidase alone induced increased keratinocyte myeloperoxidase activity, which was modulated by stem cells. These findings underscore the potential of muscle-derived mesenchymal stem/stroma cells in mitigating inflammation and restoring keratinocyte metabolism, offering insights for future cell therapy research in laminitis treatment.