Down-regulation of alpha class glutathione S-transferase by interleukin-1beta in human intestinal epithelial cells (Caco-2) in culture.
Down-regulation of alpha class glutathione S-transferase by interleukin-1beta in human intestinal epithelial cells (Caco-2) in culture.
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DOI：
10.1124/dmd.30.11.1186
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发表时间：
2002-11
期刊：
影响因子：
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通讯作者：
Laura Romero;M. Higgins;J. Gilmore;Kim Boudreau;Ann Maslen;Heather J Barker;G. Kirby
中科院分区：
文献类型：
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作者：
Laura Romero;M. Higgins;J. Gilmore;Kim Boudreau;Ann Maslen;Heather J Barker;G. Kirby
在培养的人结肠上皮细胞（Caco-2）中检测促炎细胞因子对α类谷胱甘肽S-转移酶A1和A2（GSTA 1/A2）表达的影响。在脂多糖刺激的鼠单核巨噬细胞（RAW 264.7）的条件培养基（CM）中培养的Caco-2细胞中，GSTA 1/A2 mRNA、蛋白质和活性水平出现剂量依赖性降低。中和抗白细胞介素-1 β（IL-1 β）抗体减弱了CM对GSTA 1/A2表达的抑制。此外，重组人IL-1 β在mRNA、蛋白质和活性水平以剂量相关方式降低GST α表达。IL-1受体拮抗剂预处理可减弱IL-1 β对GSTA 1/A2 mRNA水平的抑制作用。GSTA 1/A2 mRNA半衰期在对照组和IL-1 β处理的细胞中相似，表明IL-1 β对mRNA稳定性没有影响。在报告基因研究中，IL-1 β导致转染全长GSTA 1启动子-荧光素酶构建体的Caco-2细胞中荧光素酶活性的剂量相关性降低。使用截短的构建体，IL-1 β反应性被定位到编码区上游286个碱基对的区域。该区域肝核因子1（HNF-1）位点的缺失消除了IL-1 β介导的GSTA 1启动子活性抑制。这些结果表明，IL-1 β通过涉及HNF-1位点的转录机制下调培养的人肠上皮细胞中GSTA 1/A2的表达。
The influence of pro-inflammatory cytokines on alpha class glutathione S-transferase A1 and A2 (GSTA1/A2) expression was examined in human colonic epithelial cells (Caco-2) in culture. Dose-dependent reductions in GSTA1/A2 mRNA, protein, and activity levels occurred in Caco-2 cells cultured in conditioned medium (CM) from lipopolysaccharide-stimulated murine monocyte-macrophage cells (RAW 264.7). Neutralizing anti-interleukin-1beta (IL-1beta) antibodies attenuated this repression of GSTA1/A2 expression by CM. Moreover, recombinant human IL-1beta reduced GSTalpha expression at the mRNA, protein, and activity levels in a dose-related fashion. Reduction of GSTA1/A2 mRNA levels by IL-1beta was attenuated by pretreatment with IL-1 receptor antagonist. GSTA1/A2 mRNA half-lives were similar in control and IL-1beta-treated cells, indicating that IL-1beta has no effect on mRNA stability. In reporter gene studies, IL-1beta caused a dose-related reduction of luciferase activity in Caco-2 cells transfected with the full-length GSTA1 promoter-luciferase construct. Using truncated constructs, IL-1beta responsiveness was mapped to a region 286 base pairs upstream to the coding region. Deletion of a hepatic nuclear factor 1 (HNF-1) site in this region abrogated the IL-1beta-mediated repression of GSTA1 promoter activity. These results demonstrate that IL-1beta down-regulates GSTA1/A2 expression in cultured human enterocytes by a transcriptional mechanism involving an HNF-1 site.