title: Inhibition of the human leukocyte endopeptidases elastase and cathepsin G and of porcine pancreatic elastase by N-oleoyl derivatives of heparin.
abstract: N-oleoyl-heparin derivatives differing in their oleic acid and sulfate contents were synthesized and studied for their abilities to inhibit human leukocyte elastase (HLE), human leukocyte cathepsin G (CatG) and porcine pancreatic elastase (PPE) at pH 8.0, ionic strength 0.05 M and 37 degrees. Heparin (Hep) as well as N-oleoyl-heparins behaved as tight-binding, hyperbolic noncompetitive inhibitors of HLE (KiHep = 75 pM) and CatG (KiHep < 25 pM). The main driving force for the interaction between enzymes and glycosaminoglycans was electrostatic in nature. Under the condition [enzyme] >> Ki, the stoichiometries of the interaction with Hep were 1:2 (Hep:HLE) and 1:4 (Hep:CatG). Coupling one oleic acid residue to three disaccharide units of partially N-desulfated Hep, Ol1:3Hep, lowered HLE inhibition (Ki = 0.3 nM) and the stoichiometry of binding was reduced to 1:1. Re-N-sulfation of a similar derivative, Ol1:5Hep(SO4), containing one fatty acid residue for five disaccharide units, led to a substance with similar HLE inhibitory characteristics as Hep (Ki = 92 pM) and stoichiometry 1:2. Ol1:5Hep(SO4) was also a more efficient inhibitor of CatG (Ki < 33 pM) than Ol1:3Hep (Ki = 9.5 nM). The residual activities of N-oleoyl-Hep complexes with CatG were much lower than the corresponding activities in the presence of Hep. While oleate and Hep could not inhibit PPE, N-oleoyl-Hep, independently of fatty acid substitution and sulfate content, could inhibit this enzyme with Ki congruent to 60 nM and low residual activity. The efficient endopeptidase inhibitory characteristics of N-oleoyl-Hep derivatives, together with their non-anticoagulant properties and their capacity to interact with elastin, may be therapeutically useful in connective tissue degenerative diseases.
authors.affiliation: Department of Rheumatology, University Hospital, Zurich, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Baici
authors.forename: C
authors.initials: C
authors.lastname: Diczházi
authors.forename: A
authors.initials: A
authors.lastname: Neszmélyi
authors.forename: E
authors.initials: E
authors.lastname: Móczár
authors.forename: W
authors.initials: W
authors.lastname: Hornebeck
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D056649:Cathepsin G; D002403:Cathepsins / Q000037:antagonists & inhibitors*; D010450:Endopeptidases / Q000378:metabolism; D006025:Glycosaminoglycans / Q000032:analysis; D006493:Heparin / Q000031:analogs & derivatives* / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D007962:Leukocytes / Q000187:drug effects* / Q000201:enzymology; D008969:Molecular Sequence Data; D009829:Oleic Acids / Q000494:pharmacology*; D010179:Pancreas / Q000187:drug effects* / Q000201:enzymology; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors*; D012697:Serine Endopeptidases; D013552:Swine
chemical_list: D006025:Glycosaminoglycans; D009829:Oleic Acids; C072705:oleoyl heparin; D006493:Heparin; D002403:Cathepsins; D010450:Endopeptidases; D012697:Serine Endopeptidases; C534094:CTSG protein, human; D056649:Cathepsin G; D010196:Pancreatic Elastase