title: Effect of pro-inflammatory cytokines on the toxicity of the arylhydroxylamine metabolites of sulphamethoxazole and dapsone in normal human keratinocytes.
abstract: Sulphonamides, such as sulphamethoxazole (SMX) and the related sulphone dapsone (DDS), show a higher incidence of cutaneous drug reactions (CDRs) in patients with the acquired immunodeficiency syndrome (AIDS) compared with human immunodeficiency virus (HIV) negative patients. During HIV infection, pro-inflammatory cytokines such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) are increased. We hypothesized that this increase in pro-inflammatory cytokines may increase the toxicity of the arylhydroxylamine metabolites of SMX (S-NOH) and DDS (D-NOH) in keratinocytes through a reduction in glutathione (GSH) content. We evaluated the effect of TNF-alpha on GSH levels in normal human epidermal keratinocytes (NHEK) and found a significant decrease in GSH after 24h. Pre-treatment with TNF-alpha also resulted in an increase in the recovery of D-NOH, but failed to alter drug-protein covalent adduct formation in NHEK. We also evaluated the effect of TNF-alpha, IL-1 beta, interferon-gamma (IFN-gamma), lipopolysaccharide (LPS) and conditioned media (obtained from monocytes stimulated with LPS) on the cytotoxicity of pre-formed arylhydroxylamine metabolites in NHEK. Priming cells with cytokines did not significantly alter the cytotoxicity of the metabolites. The effect of pre-treatment with TNF-alpha on reactive oxygen species (ROS) generation in NHEK was also determined. While ROS formation in NHEK was increased in the presence of D-NOH, TNF-alpha did not alter the level of ROS generation. Our data suggest that the level of GSH reduction induced by pro-inflammatory cytokines does not predispose NHEK to cellular toxicity from either S-NOH or D-NOH.
authors.affiliation: Department of Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA.
authors.forename: Farah D
authors.initials: FD
authors.lastname: Khan
authors.forename: Sanjoy
authors.initials: S
authors.lastname: Roychowdhury
authors.forename: Radita
authors.initials: R
authors.lastname: Nemes
authors.forename: Piyush M
authors.initials: PM
authors.lastname: Vyas
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Woster
authors.forename: Craig K
authors.initials: CK
authors.lastname: Svensson
mesh_terms: D000890:Anti-Infective Agents / Q000633:toxicity; D016923:Cell Death / Q000187:drug effects; D002478:Cells, Cultured; D003622:Dapsone / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006898:Hydroxylamines / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology*; D007375:Interleukin-1 / Q000494:pharmacology*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D011485:Protein Binding; D017382:Reactive Oxygen Species; D013420:Sulfamethoxazole / Q000633:toxicity*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D006898:Hydroxylamines; D007375:Interleukin-1; D008070:Lipopolysaccharides; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D003622:Dapsone; D005978:Glutathione; D013420:Sulfamethoxazole