title: Heparin-like dextran derivatives as well as glycosaminoglycans inhibit the enzymatic activity of human cathepsin G.
abstract: Some synthetic dextran derivatives that mimic the action of heparin/heparan sulfate were previously shown to inhibit neutrophil elastase and plasmin. Here we report that these derivatized dextrans also inhibit cathepsin G (CatG). Dextran containing carboxymethyl and benzylamide groups (RG1150) as well as those containing carboxymethyl, sulfate and benzylamide groups (RG1192), were the most efficient inhibitors of CatG activity. RG1192 and RG1150 bind CatG with a K(i) of 0.11 and 0.17 nM, respectively, while carboxymethylated sulfated dextran (RG1503) as well as heparin, heparan sulfate and dermatan sulfate bind CatG with a 7- to 30-fold lower affinity. Variation of K(i) with ionic strength indicates that ionic interactions account for 26% of the RG1503-CatG binding energy, while binding of RG1192 or RG1150 to CatG is mainly governed by non-electrostatic interactions. This, together with the fact that these compounds both protect fibronectin and laminin against CatG-mediated degradation, suggest that specific dextran derivatives can contribute to the regulation of CatG activity.
authors.affiliation: Laboratoire de Recherche sur la Croissance Cellulaire, la Réparation et la Régénération Tissulaires, CNRS FRE-2412, Université Paris XII, Avenue du Général de Gaulle, 94000 Créteil, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Ledoux
authors.forename: Didier
authors.initials: D
authors.lastname: Merciris
authors.forename: Denis
authors.initials: D
authors.lastname: Barritault
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Caruelle
mesh_terms: D056649:Cathepsin G; D002403:Cathepsins / Q000037:antagonists & inhibitors*; D003871:Dermatan Sulfate / Q000494:pharmacology; D003911:Dextrans / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006025:Glycosaminoglycans / Q000494:pharmacology*; D006493:Heparin / Q000737:chemistry / Q000494:pharmacology*; D006497:Heparan Sulfate / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D012697:Serine Endopeptidases; D013379:Substrate Specificity
chemical_list: D056649:Cathepsin G; D002403:Cathepsins; D003871:Dermatan Sulfate; D003911:Dextrans; D004791:Enzyme Inhibitors; D006025:Glycosaminoglycans; D006493:Heparin; D006497:Heparan Sulfate; D012697:Serine Endopeptidases; C534094:CTSG protein, human