Effects of delmopinol on antimicrobial peroxidase systems and lysozyme in vitro and in human whole saliva.
Delmopinol is a new surface-active agent which can reduce plaque formation and gingivitis. This study was aimed to analyze whether delmopinol (0.0032-0.65 mM) interferes with the activity of two surface-active oral antimicrobial enzymes, salivary peroxidase and lysozyme. In addition to human whole saliva (pH 5.0 and 6.0), the experiments were done in 0.1 M phosphate buffer (pH 6.0) with purified lactoperoxidase (LPO) and myeloperoxidase (MPO). LPO and MPO were significantly inhibited in buffer by delmopinol concentrations > 6.5 mM and > or = 3.2 mM, respectively. No such inhibition was found for total peroxidase activity in mixed saliva. In vitro, delmopinol was found to desorb surface-bound peroxidases in an active form to the liquid phase. In further analyses, the possible effect of delmopinol on peroxidase-generated hypothiocyanite (HOSCN/OSCN-) was studied in saliva and buffer. No effect was found in buffer, but salivary HOSCN/OSCN- declined significantly with 6.5 mM delmopinol. This was obviously due to an enhanced decay of hypothiocyanite, rather than its reduced rate of formation. No delmopinol-related inhibition of lysozyme occurred in saliva or buffer. The results suggest that high concentration (6.4 mM -0.2%) of delmopinol may lower the concentrations of antimicrobial HOSCN/OSCN- in saliva but has no effect on human lysozyme.
Tenovuo
J
J
Department of Cariology, University of Turku, Finland.
Hannuksela
S
S
Lenander-Lumikari
M
M
D000890:Anti-Infective Agents / Q000037:antagonists & inhibitors; D002021:Buffers; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007784:Lactoperoxidase / Q000037:antagonists & inhibitors / Q000187:drug effects; D009025:Morpholines / Q000494:pharmacology*; D009113:Muramidase / Q000037:antagonists & inhibitors / Q000187:drug effects*; D009195:Peroxidase / Q000037:antagonists & inhibitors / Q000187:drug effects; D010544:Peroxidases / Q000037:antagonists & inhibitors / Q000187:drug effects*; D012463:Saliva / Q000187:drug effects / Q000201:enzymology*; D012471:Salivary Proteins and Peptides / Q000037:antagonists & inhibitors / Q000187:drug effects*; D013501:Surface-Active Agents / Q000494:pharmacology*; D013861:Thiocyanates / Q000037:antagonists & inhibitors
D000890:Anti-Infective Agents; D002021:Buffers; D004791:Enzyme Inhibitors; D009025:Morpholines; D012471:Salivary Proteins and Peptides; D013501:Surface-Active Agents; D013861:Thiocyanates; C014607:hypothiocyanite ion; C073738:delmopinol; D007784:Lactoperoxidase; D010544:Peroxidases; D009195:Peroxidase; D009113:Muramidase