Dvorák Zdenek, Vrzal Radim, Maurel Patrick, Ulrichová Jitka
Institute of Medical Chemistry and Biochemistry, Medical Faculty, Palacký University Olomouc, Hnevotínská 3, 77515 Olomouc, Czech Republic.
Chem Biol Interact. 2006 Feb 1;159(2):117-28. doi: 10.1016/j.cbi.2005.10.105. Epub 2005 Nov 10.
Natural compounds have been used in the treatment of various diseases for centuries. Herein, we investigated the effects of structurally diverse alkaloids with anti-inflammatory activity (berberine, sanguinarine, chelerythrine, and colchicine) on two important anti-inflammatory and pro-inflammatory players, i.e. glucocorticoid receptor (GR) and nuclear factor kappa B (NF-kappaB), respectively. Sanguinarine and chelerythrine elicited nuclear translocation of the p65 subunit of NF-kappaB. The nuclear import of p65 was strongly augmented by these akaloids in non-stimulated cells as well as in cells challenged with tumor necrosis factor alpha (TNFalpha). Colchicine and berberine had no effect on p65 nuclear translocation regardless of the presence or absence of TNFalpha. Colchicine caused rapid degradation of the GR protein, whereas berberine had no effect on GR content or cellular localization. Sanguinarine and chelerythrine induced accumulation of GR in the nucleus with concomitant diminution of cytosolic GR. Analyses on the transcriptional activity of GR and NF-kappaB monitored by reporter assays using HeLa cells transiently transfected with glucocorticoid response element (pGRE-LUC) and/or NF-kappaB elements fused to luciferase gene (pNF-kappaB-luc) showed that none of the compounds tested had the capability to trigger GR and/or NF-kappaB transcriptional activities, respectively. The ligand binding assay showed that colchicine and berberine are not GR ligands whereas sanguinarine and chelerythrine significantly decreased binding of (3)H-labelled dexamethasone to GR. In conclusion, structurally diverse natural antiflogistics displayed differential effects on GR and NF-kappaB in HeLa cells.
几个世纪以来，天然化合物一直被用于治疗各种疾病。在此，我们研究了具有抗炎活性的结构多样的生物碱（黄连素、血根碱、白屈菜红碱和秋水仙碱）分别对两个重要的抗炎和促炎因子，即糖皮质激素受体（GR）和核因子κB（NF-κB）的影响。血根碱和白屈菜红碱引起NF-κB的p65亚基的核转位。在未受刺激的细胞以及用肿瘤坏死因子α（TNFα）刺激的细胞中，这些生物碱强烈增强了p65的核输入。无论有无TNFα，秋水仙碱和黄连素对p65核转位均无影响。秋水仙碱导致GR蛋白快速降解，而黄连素对GR含量或细胞定位无影响。血根碱和白屈菜红碱诱导GR在细胞核中积累，同时细胞质中的GR减少。通过使用瞬时转染了糖皮质激素反应元件（pGRE-LUC）和/或与荧光素酶基因融合的NF-κB元件（pNF-κB-luc）的HeLa细胞进行报告基因检测，对GR和NF-κB的转录活性进行分析，结果表明所测试的化合物均无能力分别触发GR和/或NF-κB的转录活性。配体结合试验表明，秋水仙碱和黄连素不是GR配体，而血根碱和白屈菜红碱显著降低了3H标记的地塞米松与GR的结合。总之，结构多样的天然抗炎药对HeLa细胞中的GR和NF-κB表现出不同的作用。
