American Society of Hirudotherapy

The Coagulation Factor XIIa Inhibitor rHA-Infestin-4 Improves Outcome after Cerebral Ischemia/Reperfusion Injury in Rats

Research article published in PloS one (2016)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Drug DevelopmentKrupka et al. · PloS one, 2016

Abstract

BACKGROUND AND PURPOSE: Ischemic stroke provokes severe brain damage and remains a predominant disease in industrialized countries. The coagulation factor XII (FXII)-driven contact activation system plays a central, but not yet fully defined pathogenic role in stroke development. Here, we investigated the efficacy of the FXIIa inhibitor rHA-Infestin-4 in a rat model of ischemic stroke using both a prophylactic and a therapeutic approach. METHODS: For prophylactic treatment, animals were treated intravenously with 100 mg/kg rHA-Infestin-4 or an equal volume of saline 15 min prior to transient middle cerebral artery occlusion (tMCAO) of 90 min. For therapeutic treatment, 100 mg/kg rHA-Infestin-4, or an equal volume of saline, was administered directly after the start of reperfusion. At 24 h after tMCAO, rats were tested for neurological deficits and blood was drawn for coagulation assays. Finally, brains were removed and analyzed for infarct area and edema formation. RESULTS: Within prophylactic rHA-Infestin-4 treatment, infarct areas and brain edema formation were reduced accompanied by better neurological scores and survival compared to controls. Following therapeutic treatment, neurological outcome and survival were still improved although overall effects were less pronounced compared to prophylaxis. CONCLUSIONS: With regard to the central role of the FXII-driven contact activation system in ischemic stroke, inhibition of FXIIa may represent a new and promising treatment approach to prevent cerebral ischemia/reperfusion injury.

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

Publication typeJournal ArticleResearch Support, Non-U.S. Gov't
Indexed MeSH termsAnimalsBrainCHO CellsCricetulusDrug Evaluation, PreclinicalFactor XIIaInfarction, Middle Cerebral ArteryInsect ProteinsMaleRatsRecombinant Fusion ProteinsReperfusion Injury

Summary

Peer-reviewed research on anticoagulant and antithrombotic drug development relevant to thrombin and factor inhibition. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This rat study tested rHA-Infestin-4, a Factor XIIa inhibitor, in a transient middle cerebral artery occlusion model of ischemic stroke using both prophylactic and post-reperfusion therapeutic dosing. According to the abstract, prophylactic treatment reduced infarct area and brain edema with better neurological scores and survival than controls, while therapeutic dosing still improved outcomes though less strongly, leading the authors to propose FXIIa inhibition as a promising approach to limit cerebral ischemia/reperfusion injury. For ASH, the connection to hirudotherapy is indirect and must be stated plainly: Infestin-4 derives from the kissing bug Triatoma infestans, NOT from a medicinal leech, so this is not direct leech-secretome evidence. It is relevant only as supporting biology for the broader contact-pathway anticoagulation strategy (selective FXIIa blockade) that some leech-derived molecules also target, reinforcing why this enzyme is an attractive drug-discovery target. Honest caveat: these are preclinical findings in a small-animal stroke model and do not establish efficacy or safety in humans.

Citation

The Coagulation Factor XIIa Inhibitor rHA-Infestin-4 Improves Outcome after Cerebral Ischemia/Reperfusion Injury in Rats.

Krupka et al. · PloS one, 2016

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

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