American Society of Hirudotherapy

From natural to synthetic multisite thrombin inhibitors

Research article published in Biopolymers (1999)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportGenomics & ProteomicsSalivary PharmacologyLombardi A et al. · Biopolymers, 1999

Abstract

A large number of potent and selective therapeutic agents, useful for the treatment of several diseases, have been isolated from natural sources. For example, the most active thrombin inhibitors are those secreted by the salivary glands of leeches. One peculiar feature of these agents is the lack of any significant inhibitory cross-reaction with other serine proteinases. Hence, the knowledge of the exact mechanism of action of these molecules provides the basis for the development of new and efficient synthetic drugs. For this reason, many studies have been undertaken on the structure-activity relationships of natural thrombin inhibitors, and a large amount of detailed information has been obtained by the crystal structures of these inhibitors when complexed with thrombin. In this paper, we review natural and synthetic multisite thrombin inhibitors, whose structural aspects have been determined in detail. We also report here the approach used by us to develop a new class of synthetic, multisite directed thrombin inhibitors, named hirunorms, designed to mimic the distinctive binding mode of hirudin.

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

Publication typeJournal Article
Indexed MeSH termsAmino Acid SequenceAnimalsAntithrombinsBinding SitesDrug DesignFibrinogenHirudinsHumansLeechesModels, MolecularMolecular Sequence DataProtein Conformation

Summary

A large number of potent and selective therapeutic agents, useful for the treatment of several diseases, have been isolated from natural sources.

Why This Matters for Hirudotherapy

This paper reviews natural and synthetic multisite thrombin inhibitors whose structural aspects have been determined in detail, noting that the most active thrombin inhibitors are those secreted by the salivary glands of leeches. The authors discuss how detailed structural information from crystal structures of these natural inhibitors complexed with thrombin provides the basis for developing new synthetic drugs, and report their own approach to designing a new class of synthetic multisite-directed thrombin inhibitors called hirunorms, designed to mimic the distinctive binding mode of hirudin. This is relevant to ASH's domain as the abstract explicitly identifies leech salivary gland secretions as the source of the most potent natural thrombin inhibitors and uses hirudin as a structural model for drug design. The caveat is that the paper's scope is molecular design and structural pharmacology rather than clinical application.

Citation

From natural to synthetic multisite thrombin inhibitors

Lombardi A et al. · Biopolymers, 1999

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

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