Khan Farah D, Roychowdhury Sanjoy, Nemes Radita, Vyas Piyush M, Woster Patrick M, Svensson Craig K
Department of Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA.
Toxicology. 2006 Feb 1;218(2-3):90-9. doi: 10.1016/j.tox.2005.10.002. Epub 2005 Nov 14.
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.
与人类免疫缺陷病毒（HIV）阴性患者相比，磺胺类药物，如磺胺甲恶唑（SMX）和相关的砜类药物氨苯砜（DDS），在获得性免疫缺陷综合征（AIDS）患者中引起皮肤药物反应（CDR）的发生率更高。在HIV感染期间，促炎细胞因子如白细胞介素-1β（IL-1β）和肿瘤坏死因子-α（TNF-α）会增加。我们推测，促炎细胞因子的这种增加可能通过降低谷胱甘肽（GSH）含量，增加角质形成细胞中SMX的芳基羟胺代谢产物（S-NOH）和DDS的芳基羟胺代谢产物（D-NOH）的毒性。我们评估了TNF-α对正常人表皮角质形成细胞（NHEK）中GSH水平的影响，发现24小时后GSH显著降低。用TNF-α预处理也导致D-NOH的回收率增加，但未能改变NHEK中药物-蛋白质共价加合物的形成。我们还评估了TNF-α、IL-1β、干扰素-γ（IFN-γ）、脂多糖（LPS）和条件培养基（从用LPS刺激的单核细胞中获得）对NHEK中预先形成的芳基羟胺代谢产物细胞毒性的影响。用细胞因子预处理细胞并没有显著改变代谢产物的细胞毒性。还确定了用TNF-α预处理对NHEK中活性氧（ROS）生成的影响。虽然在D-NOH存在下NHEK中的ROS形成增加，但TNF-α并没有改变ROS的生成水平。我们的数据表明，促炎细胞因子诱导的GSH降低水平并不会使NHEK对S-NOH或D-NOH的细胞毒性更敏感。
