title: Photodynamic effect of protoporphyrin diarginate (PPArg2) on methicillin-resistant Staphylococcus aureus and human dermal fibroblasts.
abstract: The worldwide rise in the antibiotic resistance of bacteria forces the development of alternative antimicrobial treatments. A potential approach is photodynamic inactivation (PDI). The aim of the present study was to determine the phototoxicity of protoporphyrin diarginate (PPArg(2)) against methicillin-resistant Staphylococcus aureus and human dermal fibroblasts. Different concentrations (0 to 20 microM) of PPArg(2) and light dose of 6 J cm(-2) were tested. Cell viability was evaluated using the methylthiazoletetrazolium (MTT) assay. Incubation with 10 microM followed by illumination yielded a 3.6 log(10)-unit reduction in the viable count for Staphylococcus aureus. At the same experimental conditions, only 22.5% of the fibroblasts were photoinactivated. Protoporphyrin diarginate at concentrations up to 20 microM demonstrated no toxicity towards S. aureus or fibroblasts when not irradiated. These results suggest that the protoporphyrin diarginate exerts a high bactericidal effect against methicillin-resistant S. aureus strain without harming eukaryotic cells.
authors.affiliation: Department of Biotechnology, Division of Molecular Diagnostics, University of Gdansk and Medical University of Gdansk, Gdańsk, Poland. grinholc@biotech.ug.gda.pl
authors.forename: Mariusz
authors.initials: M
authors.lastname: Grinholc
authors.forename: Anna
authors.initials: A
authors.lastname: Kawiak
authors.forename: Julianna
authors.initials: J
authors.lastname: Kurlenda
authors.forename: Alfreda
authors.initials: A
authors.lastname: Graczyk
authors.forename: Krzysztof P
authors.initials: KP
authors.lastname: Bielawski
mesh_terms: D001120:Arginine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D020405:Dermis / Q000166:cytology*; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D008027:Light; D008712:Methicillin / Q000494:pharmacology*; D016106:Methicillin Resistance; D008954:Models, Biological; D010777:Photochemistry / Q000379:methods; D017319:Photosensitizing Agents / Q000494:pharmacology; D011524:Protoporphyrins / Q000494:pharmacology*; D012867:Skin / Q000166:cytology / Q000378:metabolism; D013211:Staphylococcus aureus / Q000378:metabolism*; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology
chemical_list: D017319:Photosensitizing Agents; D011524:Protoporphyrins; D013778:Tetrazolium Salts; D013844:Thiazoles; D001120:Arginine; C022616:thiazolyl blue; D008712:Methicillin