Concentration Dependent Influence of Lipopolysaccharides on Separation of Hoof Explants and Supernatant Lactic Acid Concentration in an Ex Vivo/In Vitro Laminitis Model.

This study investigates how different concentrations of lipopolysaccharides (LPS) affect horse hoof cells and tissue in a lab-based laminitis model. The researchers discovered that LPS damages hoof tissue integrity and alters lactic acid production, despite having no harmful effects on individual hoof cells. The results underscore the need for further research on endotoxins like LPS in understanding and combating laminitis.

Objective of Study

• The study aimed to investigate the effect of different concentrations of lipopolysaccharides (LPS), a type of endotoxin, on epidermal and dermal hoof cells as well as hoof explants. This was carried out in an attempt to better understand the pathogenesis of laminitis, a common and damaging horse disease.

Research Methodology

• The researchers used isolated cells and tissue explants from horse hooves and treated them with different concentrations of LPS (0, 2.5, 5, 10, and 100 μg/mL).
• They examined the effects of these treatments on cell viability and tissue integrity.
• They also measured glucose, acetic acid, lactic acid, and propionic acid concentrations in the explant supernatant to assess the energy metabolism of the hoof tissue.

Findings

• The study found that LPS did not show toxic effects on individual epidermal or dermal cells from horse hooves.
• However, the force required to separate the LPS treated hoof explants decreased in a concentration-dependent manner, indicating a detrimental effect on tissue integrity. Hoof explants treated with higher concentrations of LPS (10 and 100 μg/mL) required significantly less force to separate compared to control explants.
• The researchers also found alterations in lactic acid concentrations, which were significantly decreased in explants incubated with LPS of 5, 10, or 100 μg/mL. Other metabolic markers, such as glucose, acetic acid and propionic acid, remained unaffected by LPS treatment.

Interpretation and Implications

• The findings suggest that LPS do not harm individual epidermal and dermal cells isolated from hoof tissue. However, these endotoxins can impair the integrity of the entire hoof tissue, as evidenced in the explant study. The results indicate that while LPS might not directly harm the cells, they can cause damage at a tissue level.
• Additionally, the alteration of lactic acid levels in the hoof tissue implies that LPS can interfere with energy metabolism, which could be a contributory factor in the development of laminitis.
• This study underscores the importance of further exploring the role of endotoxins in the development of laminitis, which could inform better prevention, diagnosis, and treatment strategies for the disease in horses.