title: Biological effects of nitric oxide generated by an atmospheric pressure gas-plasma on human skin cells.
abstract: Physical plasmas which contain a mixture of different radicals, charged species and UV-radiation, have recently found entry in various medical applications. Though first clinical trials are underway nothing is known about the plasma components mediating the biological effects seen and safety concerns have been neglected. We here use for the first time a plasma device equipped with a bent quartz capillary to omit UV-radiation by directing the gas flux only, containing high concentrations of NO, onto cultured human skin cells. This enables us to compare the effects of plasma produced radical species alone - mainly NO - and in combination with the also emitted UV-radiation on cells. Evaluation of cell death after different treatment times with the capillary present shows no sign of apoptosis in primary human keratinocytes even after 15 min plasma exposure. In human skin endothelial cells however, toxicity is elevated after treatment for more than 10 min. In contrast, without the capillary treatment of both cell types results in maximal cell death after 10 min. Measuring nitrite and nitrosothiols reveals that plasma-treatment leads to an increase of these NO-products in buffer solution and cell culture medium. Using an intracellular fluorescent NO-probe and analysing the nitrosation status of plasma exposed skin cells we can prove that NO indeed reaches and penetrates into these cells. Non-toxic exposure times modulate proliferation in both cell types used, indicating that the gas species, mainly NO, are biological active.
authors.affiliation: Institute of Molecular Medicine, Research Group Immunobiology, Heinrich-Heine-University Duesseldorf, Germany. liebmann@uni-duesseldorf.de
authors.forename: Joerg
authors.initials: J
authors.lastname: Liebmann
authors.forename: Joachim
authors.initials: J
authors.lastname: Scherer
authors.forename: Nikita
authors.initials: N
authors.lastname: Bibinov
authors.forename: Priyadarshini
authors.initials: P
authors.lastname: Rajasekaran
authors.forename: Reinhold
authors.initials: R
authors.lastname: Kovacs
authors.forename: Roland
authors.initials: R
authors.lastname: Gesche
authors.forename: Peter
authors.initials: P
authors.lastname: Awakowicz
authors.forename: Victoria
authors.initials: V
authors.lastname: Kolb-Bachofen
mesh_terms: D000704:Analysis of Variance; D017209:Apoptosis / Q000187:drug effects; D002461:Cell Line, Transformed; D049109:Cell Proliferation; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D009573:Nitrites / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D009603:Nitroso Compounds / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D058626:Plasma Gases / Q000494:pharmacology*; D012867:Skin / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000032:analysis / Q000737:chemistry / Q000378:metabolism
chemical_list: D009573:Nitrites; D009603:Nitroso Compounds; D058626:Plasma Gases; D013438:Sulfhydryl Compounds; D009569:Nitric Oxide