American Society of Hirudotherapy

Dabigatran prevents lipopolysaccharide mediated apoptosis in zebrafish through a thrombin independent mechanism

Research article published in Shock (Augusta, Ga.) (2026)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsFleischmann et al. · Shock (Augusta, Ga.), 2026

Abstract

Endotoxemia is a feature of sepsis pathogenesis and has also been found to mediate the pathophysiology of multiple inflammatory conditions. In this work, we use a lipopolysaccharide (LPS) induced endotoxemia model in zebrafish to identify novel mediators of LPS toxicity. We performed transcriptomic studies on LPS-treated larvae, followed by in silico analysis, which revealed associations between the signatures of LPS-treated embryos and those of drugs involving diverse pathways. In parallel, we performed an in vivo screen using >1,500 FDA-approved compounds and identified multiple novel small molecules that reduced inflammation and prevented LPS toxicity. We focused on the direct thrombin inhibitor dabigatran, which was identified through both the in vivo and in silico analyses. We found that dabigatran co-administration significantly reduced the expression of inflammatory cytokines and completely protected zebrafish from endotoxemic death due to LPS. Surprisingly, we found that this protection occurs in prothrombin mutant fish, proving that protection from endotoxemia occurs independently of the anticoagulant function of dabigatran. We additionally found that dabigatran administration significantly decreased nitric oxide production and apoptosis compared to LPS treatment alone, suggesting possible mechanisms by which protection from endotoxemia is achieved. In summary, we identify several novel small molecules that prevent LPS-induced endotoxemia and show that one such small molecule, dabigatran, exerts a thrombin-independent effect on nitric oxide production and apoptosis. This and the other identified small molecules warrant further exploration in inflammatory conditions including sepsis.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This zebrafish study screened over 1,500 FDA-approved compounds in a lipopolysaccharide (LPS) endotoxemia model and found that the direct thrombin inhibitor dabigatran sharply reduced inflammatory cytokine expression and fully protected larvae from endotoxemic death, while decreasing nitric oxide production and apoptosis; notably, protection persisted in prothrombin-mutant fish, showing the effect was independent of dabigatran's anticoagulant action. For hirudotherapy this is a useful adjacent data point in the thrombin-inhibitor story: it illustrates that molecules acting on the thrombin axis can carry anti-inflammatory activity decoupled from clotting effects, the same conceptual space occupied by leech-derived antithrombins such as hirudin. The honest caveat is that this is a preclinical small-animal screen in zebrafish testing a synthetic small molecule, not a leech product and not a clinical trial; it supports hypothesis generation about thrombin-pathway pharmacology, nothing about leech efficacy in patients.

Citation

Dabigatran prevents lipopolysaccharide mediated apoptosis in zebrafish through a thrombin independent mechanism.

Fleischmann et al. · Shock (Augusta, Ga.), 2026

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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