title: Extracellular catalase activity protects cysteine cathepsins from inactivation by hydrogen peroxide.
abstract: The resistance of secreted cysteine cathepsins to peroxide inactivation was evaluated using as model THP-1 cells. Differentiated cells released mostly cathepsin B, but also cathepsins H, K, and L, with a maximum of endopeptidase activity at day 6. Addition of non-cytotoxic concentrations of H(2)O(2) did not affect mRNA expression levels and activity of cathepsins, while the catalase activity remained also unchanged, consistently with RT-PCR analysis. Conversely inhibition of extracellular catalase led to a striking inactivation of secreted cysteine cathepsins by H(2)O(2). This report suggests that catalase may participate in the protection of extracellular cysteine proteases against peroxidation.
authors.affiliation: INSERM U 618, Protéases et Vectorisation Pulmonaires, Equipe Protéases et Pathologies Pulmonaires, Tours F-37000, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Hervé-Grépinet
authors.forename: Florian
authors.initials: F
authors.lastname: Veillard
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Godat
authors.forename: Nathalie
authors.initials: N
authors.lastname: Heuzé-Vourc'h
authors.forename: Fabien
authors.initials: F
authors.lastname: Lecaille
authors.forename: Gilles
authors.initials: G
authors.lastname: Lalmanach
mesh_terms: D001483:Base Sequence; D002374:Catalase / Q000378:metabolism*; D002403:Cathepsins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D017931:DNA Primers; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D006861:Hydrogen Peroxide; D002374:Catalase; D002403:Cathepsins