Drabikova Katarina, Perecko Tomas, Nosal Radomir, Rackova Lucia, Ambrozova Gabriela, Lojek Antonin, Smidrkal Jan, Harmatha Juraj, Jancinova Viera
Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Bratislava, Slovakia.
Neuro Endocrinol Lett. 2010;31 Suppl 2:73-8.
Activated phagocytes, generating a variety of powerful inflammatory mediators, such as oxygen and nitrogen species, may participate in oxidative stress-mediated inflammation and organ toxicity. At present, great attention is devoted to the important class of phenolic compounds - coumarins - due to their antiinflammatory/antioxidant activities. We compared two synthetic phenylcoumarins: 7-hydroxy-3-(4´-hydroxyphenyl) coumarin (HHC; 0.01-100 µmol/l) and its hydrogenated analogue: 7-hydroxy-3-(4´-hydroxyphenyl)-3,4-dihydrocoumarin (HHDC; 0.01-100 µmol/l) as their ability to inhibit reactive oxygen species (ROS) generation in human neutrophils and nitric oxide (NO) production by RAW 264.7 macrophages in vitro, with respect to some of their physicochemical characteristics.
ROS production was measured with luminol-enhanced chemiluminescence (CL) in the microplate luminometer Immunotech LM-01T, nitrite formation was determined by the Griess reaction - spectrophotometrically. The radical scavenging assays were employed to assess the antiradical activity values. The relevant physico-chemical parameters of the compounds tested, electronic and hydrophobic, were determined experimentally as well as by suitable computational programmes.
Both HHC and HHDC were found to decrease significantly (p<0.01) CL of whole blood stimulated with phorbol myristate acetate (PMA) from the concentration of 1 µmol/l. While HHC significantly inhibited CL stimulated by A23187 and opsonized zymosan (OpZ), HHDC was ineffective. Unlike HHDC, HHC in the concentrations of 10 and 100 µmol/l significantly (p<0.01) reduced NO formation in lipopolysaccharide (LPS) -stimulated murine macrophages RAW 264.7. HHC possessed the higher free radical reducing efficacy in accordance with its more favourable values of electronic parameters in comparison with HHDC.
Our results show the different inhibitory effects of HHC and HHDC on phagocytic activity that might be the result of their diverse free radical scavenging properties and lipophilicity features.
活化的吞噬细胞可产生多种强大的炎症介质，如氧和氮类物质，可能参与氧化应激介导的炎症和器官毒性。目前，由于其抗炎/抗氧化活性，一类重要的酚类化合物——香豆素受到了极大关注。我们比较了两种合成苯基香豆素：7-羟基-3-(4´-羟基苯基)香豆素（HHC；0.01 - 100 μmol/l）及其氢化类似物：7-羟基-3-(4´-羟基苯基)-3,4-二氢香豆素（HHDC；0.01 - 100 μmol/l）在体外抑制人中性粒细胞中活性氧（ROS）生成以及RAW 264.7巨噬细胞中一氧化氮（NO）产生的能力，并研究了它们的一些物理化学特性。
用鲁米诺增强化学发光法（CL）在酶标仪Immunotech LM - 01T中测定ROS生成，通过格里斯反应分光光度法测定亚硝酸盐形成。采用自由基清除试验评估抗自由基活性值。通过实验以及合适的计算程序测定所测试化合物的相关物理化学参数，包括电子参数和疏水参数。
发现HHC和HHDC在浓度为1 μmol/l时均能显著降低（p<0.01）佛波酯（PMA）刺激的全血的CL。虽然HHC能显著抑制A23187和调理酵母聚糖（OpZ）刺激的CL，但HHDC无效。与HHDC不同，浓度为10和100 μmol/l的HHC能显著（p<0.01）减少脂多糖（LPS）刺激的小鼠巨噬细胞RAW 264.7中NO的形成。与HHDC相比，HHC因其更有利的电子参数值而具有更高的自由基还原功效。
我们的结果表明HHC和HHDC对吞噬活性具有不同的抑制作用，这可能是由于它们不同的自由基清除特性和亲脂性特征所致。
