American Society of Hirudotherapy

Free radicals inactivate human neutrophil elastase and its inhibitors with comparable efficiency

Comparative study published in Biochemical and biophysical research communications (1989)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Observational studyDrug DevelopmentDean RT et al. · Biochemical and biophysical research communications, 1989

Abstract

Free radicals produced in a Fenton reaction (H202/Cu), modelling some xenobiotic and cell-mediated inflammatory affronts, efficiently inactivated the elastase-inhibitor eglin, but equally, human neutrophil elastase itself. Elastase activity was not regenerated from proteinase/inhibitor complexes during radical attack. Three different elastase inhibitors, eglin, secretory leukocyte proteinase inhibitor and alpha-1-proteinase inhibitor were all similarly sensitive to inactivation. Unlike certain oxidants which can selectively inactivate alpha-1-proteinase inhibitor, free radicals may influence comparably the availability of both proteinase inhibitors and their targets.

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

Publication typeComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't
Indexed MeSH termsBlood ProteinsCopperEnzyme ActivationFree RadicalsHumansHydrogen PeroxideNeutrophilsPancreatic ElastaseProtease InhibitorsProteinsSerpinsalpha 1-Antitrypsin

Summary

Free radicals produced in a Fenton reaction (H202/Cu), modelling some xenobiotic and cell-mediated inflammatory affronts, efficiently inactivated the elastase-inhibitor eglin, but equally, human neutrophil elastase itself.

Why This Matters for Hirudotherapy

This study examined how free radicals generated in a Fenton reaction (H2O2/Cu) inactivate human neutrophil elastase and several proteinase inhibitors, including eglin, secretory leukocyte proteinase inhibitor, and alpha-1-proteinase inhibitor, in vitro. Elastase activity was not regenerated from proteinase/inhibitor complexes during radical attack, and all three inhibitors were similarly sensitive to inactivation, suggesting free radicals comparably influence the availability of both proteinase inhibitors and their targets. The abstract identifies eglin only as an elastase-inhibitor and provides no information about its biological origin. Because the abstract contains no mention of leeches, leech saliva, leech secretome, or hirudotherapy, no defensible connection to ASH's domain can be drawn from this source alone; any leech-origin claim would require external information absent from the abstract.

Citation

Free radicals inactivate human neutrophil elastase and its inhibitors with comparable efficiency

Dean RT et al. · Biochemical and biophysical research communications, 1989

DOI

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

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