Perregaux D G, Dean D, Cronan M, Connelly P, Gabel C A
Department of Cancer, Pfizer Inc., Groton, Connecticut 06340, USA.
Mol Pharmacol. 1995 Sep;48(3):433-42.
Cytokine-suppressing anti-inflammatory drugs (CSAIDs) are reported to inhibit production of proinflammatory cytokines such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) by affecting a stress-induced kinase. To gain a better understanding of the selectivity and cellular dynamics of this type of inhibitor, we studied in vitro the prototype member of this class of agents, SKF86002. Lipopolysaccharide (LPS)-activated human monocytes treated with SKF86002 produced less proIL-1 beta but normal amounts of the noncytokine lysozyme. Two-dimensional gel analysis indicated that only eight polypeptides produced by monocytes were decreased by SKF86002. Inhibition of IL-1 beta production was achieved by affecting two separate steps in this cytokine's biogenesis. First, SKF86002 lowered proIL-1 beta synthesis. By pulse-chase analysis, this effect was localized to a posttranscriptional site of action; maximal inhibition was observed when SKF86002 was added at the time of cytokine translation. Exposure of monocytes to SKF86002 for > 2 hr led to a loss of IL-1 beta inhibitory activity, suggesting that these cells adapted to this agent. Moreover, LPS-activated monocytes that were pretreated with granulocyte-macrophage colony-stimulating factor were less sensitive to the proIL-1 beta inhibitory effect of SKF86002, and production of proIL-1 beta by cytokine-stimulated human fibroblasts was impaired only modestly by the CSAID. A second effect of SKF86002 was to inhibit release of IL-1 beta into the medium in response to high concentrations of LPS; this effect is observed only with freshly isolated human monocytes as other IL-1 beta-producing cells do not release significant cytokine in response to LPS. The ability of SKF86002 to inhibit this posttranslational mechanism was mimicked by lysosomotrophic agents such as chloroquine, quinacrine, and methylamine. In contrast, chloroquine, and quinacrine were not effective inhibitors of monocyte proIL-1 beta translation. Thus, SKF86002 inhibits IL-1 beta production by affecting at least two distinct steps in the biosynthesis of this cytokine. Manifestation of these two effects, however, is dependent on the length of time for which cells are exposed to this agent and the nature of the cytokine-producing cellular system.
据报道，细胞因子抑制性抗炎药物（CSAIDs）通过影响一种应激诱导激酶来抑制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）的产生。为了更好地理解这类抑制剂的选择性和细胞动力学，我们在体外研究了这类药物的原型成员SKF86002。用SKF86002处理脂多糖（LPS）激活的人单核细胞，产生的前体IL-1β减少，但非细胞因子溶菌酶的量正常。二维凝胶分析表明，SKF86002仅使单核细胞产生的8种多肽减少。通过影响IL-1β生物合成中的两个独立步骤实现了对IL-1β产生的抑制。首先，SKF86002降低了前体IL-1β的合成。通过脉冲追踪分析，这种作用定位于转录后作用位点；当在细胞因子翻译时加入SKF86002时观察到最大抑制作用。单核细胞暴露于SKF86002超过2小时会导致IL-1β抑制活性丧失，表明这些细胞对该药物产生了适应性。此外，用粒细胞-巨噬细胞集落刺激因子预处理的LPS激活的单核细胞对SKF86002的前体IL-1β抑制作用不太敏感，并且CSAID仅适度损害细胞因子刺激的人成纤维细胞产生前体IL-1β的能力。SKF86002的第二个作用是抑制IL-1β对高浓度LPS的反应而释放到培养基中；仅在新鲜分离的人单核细胞中观察到这种作用，因为其他产生IL-1β的细胞对LPS不释放大量细胞因子。SKF86002抑制这种翻译后机制的能力被溶酶体营养剂如氯喹、奎纳克林和甲胺模拟。相反，氯喹和奎纳克林不是单核细胞前体IL-1β翻译的有效抑制剂。因此，SKF86002通过影响IL-1β生物合成中的至少两个不同步骤来抑制IL-1β的产生。然而，这两种作用的表现取决于细胞暴露于该药物的时间长度以及产生细胞因子的细胞系统的性质。
