Misoprostol Inhibits Lipopolysaccharide-Induced Pro-inflammatory Cytokine Production by Equine Leukocytes.
Authors: Martin Emily Medlin, Messenger Kristen M, Sheats Mary Katherine, Jones Samuel L
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: Misoprostol as an Anti-inflammatory Agent in Equine Medicine Excessive production of pro-inflammatory cytokines—particularly TNF-α, IL-1β, IL-6 and IL-8—drives tissue damage in serious equine conditions including sepsis and laminitis, yet targeted cytokine therapies remain limited in horses. This in vitro study investigated whether misoprostol, a prostaglandin E1 analogue currently used for gastric protection, could suppress cytokine production by stimulating E-prostanoid receptors and raising intracellular cyclic AMP levels—a mechanism known to dampen inflammation in human leukocytes. Leukocyte-rich plasma from 12 healthy horses was exposed to lipopolysaccharide (to trigger inflammation) with misoprostol added either before or after stimulation, with results analysed across 23 cytokines and mRNA expression of four key cytokines. Misoprostol significantly reduced TNF-α and IL-6 production at both protein and mRNA levels regardless of timing, and suppressed IL-1β transcription; however, IL-8 responses were unaffected, and IL-1β protein levels showed unexpected augmentation when misoprostol was given before LPS challenge at 6 hours—suggesting timing-dependent and cytokine-specific effects. Whilst these findings are promising for repurposing an existing, well-tolerated drug, the disconnect between mRNA and protein levels and the variable IL-1β response highlight the complexity of equine cytokine regulation; in vivo studies are essential before considering misoprostol for inflammatory conditions like laminitis or endotoxaemia.
Read the full abstract on PubMed
Practical Takeaways
- •Misoprostol, already used safely as a gastroprotectant in horses, shows promise as a cytokine-targeting therapy for inflammatory conditions like sepsis and laminitis
- •In vitro results are encouraging but in vivo studies are needed before clinical application; timing and dosing of misoprostol treatment may affect outcomes differently depending on the cytokine target
- •The drug's selective effects on different cytokines suggest it may require careful clinical evaluation and potentially combination therapy approaches
Key Findings
- •Misoprostol pre- and post-treatment inhibited LPS-induced TNF-α and IL-6 protein production in equine leukocytes
- •Misoprostol had no effect on IL-8 protein production despite inhibiting IL-8 mRNA
- •Misoprostol pretreatment enhanced IL-1β protein at 6 hours but posttreatment inhibited IL-1β at 24 hours of LPS stimulation
- •Anti-inflammatory effects were cytokine-specific and differed between mRNA and protein levels