American Society of Hirudotherapy

The derivatives of hirudin-like peptides from the Poecilobdella manillensis exhibit antithrombotic and anti-ischemic stroke effects

Research article published in International journal of biological macromolecules (2025)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Drug DevelopmentKhalid M et al. · International journal of biological macromolecules, 2025

Abstract

Almost all currently approved anticoagulants interfere with hemostasis and increase the risk of bleeding complications. Thus, there is a critical need for safer anti-thrombotic drugs without bleeding risk. Hirudin has demonstrated potent antithrombotic properties, but is clinically limited due to its high bleeding risk. Hirudin variants such as bivalirudin have been developed to address this issue, yet present a similar proportional risk of bleeding. In this study, several hirudin-like peptides were identified from the salivary gland transcriptome of Poecilobdella manillensis. Guided by the structural design principles of bivalirudin, derivatives of these hirudin-like peptides were synthesized and evaluated for their antithrombotic efficacy and safety in thrombosis and ischemic stroke. Results suggested that derived peptides PM3, PM4, PM6 and PM7 can effectively inhibited the activity of thrombin in vitro. Furthermore, PM4, PM6 and PM7 exhibited robust anticoagulant activity in vivo. Importantly, PM4 and PM7 exhibited significantly lower bleeding risk compared to bivalirudin, as well as comparable efficacy in mitigating intracerebral thrombosis in a transient middle cerebral artery occlusion mouse model, without inducing intracerebral hemorrhage. These findings highlight the therapeutic potential of hirudin-like peptide derivatives as promising candidates for the treatment of thrombosis and ischemic stroke, combining efficacy with an improved safety profile.

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

Publication typeJournal Article
Indexed MeSH termsAnimalsHirudinsFibrinolytic AgentsMiceIschemic StrokePeptidesMaleDisease Models, AnimalAnticoagulantsThrombinThrombosisPeptide Fragments

Summary

Almost all currently approved anticoagulants interfere with hemostasis and increase the risk of bleeding complications.

Why This Matters for Hirudotherapy

This study identified hirudin-like peptides from the salivary gland transcriptome of Poecilobdella manillensis and synthesized derivatives guided by bivalirudin structural design principles. Derivatives PM3, PM4, PM6, and PM7 effectively inhibited thrombin in vitro; PM4, PM6, and PM7 exhibited anticoagulant activity in vivo; and PM4 and PM7 showed significantly lower bleeding risk than bivalirudin while demonstrating comparable efficacy in mitigating intracerebral thrombosis in a transient middle cerebral artery occlusion mouse model without inducing intracerebral hemorrhage. This is directly relevant to ASH's domain as it explores leech-derived hirudin variants as potentially safer antithrombotic and anti-stroke agents. Caveat: Findings are preclinical, based on mouse thrombosis and ischemic stroke models with synthetic peptide derivatives, not live leech therapy; no human safety or efficacy data are presented.

Citation

The derivatives of hirudin-like peptides from the Poecilobdella manillensis exhibit antithrombotic and anti-ischemic stroke effects

Khalid M et al. · International journal of biological macromolecules, 2025

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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