Endothelial cells present an innate resistance to glucocorticoid treatment: implications for therapy of primary vasculitis
Endothelial cells present an innate resistance to glucocorticoid treatment: implications for therapy of primary vasculitis
复制标题
DOI：
10.1136/annrheumdis-2011-200530
复制
发表时间：
2012-05-01
影响因子：
27.4
通讯作者：
Viemann, Dorothee
中科院分区：
文献类型：
--
作者：
Koenen, Paola;Barczyk, Katarzyna;Viemann, Dorothee
背景与其他慢性炎症性疾病相比，单独使用糖皮质激素并不能维持原发性血管炎的充分缓解。这种治疗失败的原因尚不清楚。 目的 研究糖皮质激素对内皮细胞 (EC) 的分子效应，并阐明其分子途径。 方法 采用比较方法，用糖皮质激素或糖皮质激素与肿瘤坏死因子 α (TNF α) 长期和短期治疗人类微血管和大血管 EC 以及单核细胞。应用微阵列技术、复杂的生物信息学检查和定量逆转录 PCR 分析基因表达变化。通过细胞分级分析和免疫荧光显微镜追踪糖皮质激素受体易位过程。结果在EC中，在单独糖皮质激素暴露和糖皮质激素治疗TNFα诱导的促炎反应后，糖皮质激素完全不能抑制免疫反应基因的表达。相比之下，在单核细胞中观察到促炎基因的显着下调。该研究表明，糖皮质激素受体在 EC 和单核细胞中表达相当，并证明配体结合的糖皮质激素受体具有良好的易位性，从而允许基因组糖皮质激素发挥作用。精细的基因表达分析表明，在 EC 中发生反式激活，并导致糖皮质激素对生长和代谢产生副作用，而单核细胞中的反式抑制介导的抗炎作用则缺失。 SAP30（Sin3A-组蛋白脱乙酰酶复合物的重要组成部分）在 EC 中诱导不足，表明由于共阻遏物缺失而导致反式阻抑受损。 结论 EC 对抗炎糖皮质激素作用的明显无反应与糖皮质激素受体易位下游缺陷相关，该缺陷不影响反式激活，但影响反式阻抑。这些发现为原发性血管炎患者糖皮质激素治疗效果不佳提供了第一个分子线索。
Background In contrast to other chronic inflammatory diseases glucocorticoids alone do not maintain sufficient remission in primary vasculitis. The reasons for this therapeutic failure remain unclear.Objectives To investigate the molecular effects glucocorticoids exert on endothelial cells (EC) and to elucidate the molecular pathways responsible.Methods A comparative approach was used to treat human micro and macrovascular EC as well as monocytes long and short term with glucocorticoids or glucocorticoids and tumour necrosis factor alpha (TNF alpha). Gene expression changes were analysed applying microarray technology, sophisticated bioinformatic work-up and quantitative reverse transcription PCR. Glucocorticoid receptor translocation processes were traced by cell fractionation assays and immunofluorescence microscopy.Results In EC glucocorticoids completely failed to inhibit the expression of immune response genes both after sole glucocorticoid exposure and glucocorticoid treatment of a TNF alpha-induced proinflammatory response. In contrast, an impressive downregulation of proinflammatory genes was seen in monocytes. The study demonstrated that the glucocorticoid receptor is comparably expressed in EC and monocytes, and demonstrated good translocation of ligand-bound glucocorticoid receptor allowing genomic glucocorticoid actions. Refined gene expression analysis showed that in EC transactivation takes place and causes glucocorticoid side effects on growth and metabolism whereas transrepression-mediated anti-inflammatory effects as in monocytes are missing. Insufficient induction of SAP30, an important constituent of the Sin3A-histone deacetylase complex, in EC suggests impairment of transrepression due to co-repressor absence.Conclusions The impressive unresponsiveness of EC to anti-inflammatory glucocorticoid effects is associated with deficiencies downstream of glucocorticoid receptor translocation not affecting transactivation but transrepression. The findings provide the first molecular clues to the poor benefit of glucocorticoid treatment in patients with primary vasculitis.