Potent Trivalent Inhibitors of Thrombin through Hybridization of Salivary Sulfopeptides from Hematophagous Arthropods
Basic science / drug design published in Angew Chem Int Ed Engl (2021)
Abstract
Blood feeding arthropods, such as leeches, ticks, flies and mosquitoes, provide a privileged source of peptidic anticoagulant molecules. These primarily operate through inhibition of the central coagulation protease thrombin by binding to the active site and either exosite I or exosite II. Herein, we describe the rational design of a novel class of trivalent thrombin inhibitors that simultaneously block both exosites as well as the active site. These engineered hybrids were synthesized using tandem diselenide-selenoester ligation (DSL) and native chemical ligation (NCL) reactions in one-pot. The most potent trivalent inhibitors possessed femtomolar inhibition constants against α-thrombin and were selective over related coagulation proteases. A lead hybrid inhibitor possessed potent anticoagulant activity, blockade of both thrombin generation and platelet aggregation in vitro and efficacy in a murine thrombosis model at 1 mg kg-1 . The rational engineering approach described here lays the foundation for the development of potent and selective inhibitors for a range of other enzymatic targets that possess multiple sites for the disruption of protein-protein interactions, in addition to an active site.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Rational design of trivalent thrombin inhibitors by hybridizing leech, tick, fly, and mosquito sulfopeptides. Engineered hybrids achieve femtomolar Ki against alpha-thrombin and effective antithrombotic activity in a murine thrombosis model at 1 mg/kg.
Why This Matters for Hirudotherapy
This study describes the rational design of novel trivalent thrombin inhibitors inspired by peptidic anticoagulant molecules from blood-feeding arthropods, including leeches, that simultaneously block thrombin's active site and both exosites. The engineered hybrids achieved femtomolar inhibition constants against α-thrombin, selectivity over related coagulation proteases, and efficacy in a murine thrombosis model at 1 mg kg⁻¹. For ASH and hirudotherapy, this work is relevant because medicinal leeches are named among the hematophagous arthropods whose salivary anticoagulants—exemplified by hirudin—serve as starting points for such inhibitor engineering, and the multi-site blockade strategy extends principles learned from leech-derived thrombin inhibitors. The key caveat is that this is a preclinical study in mice using synthetic engineered compounds, not leech-derived preparations; no clinical efficacy or safety in humans has been demonstrated.
Citation
Potent Trivalent Inhibitors of Thrombin through Hybridization of Salivary Sulfopeptides from Hematophagous Arthropods.
Agten SM et al. · Angewandte Chemie, 2021
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