Department of Bio-medical Sciences, University of Catania, Viale A. Doria, 6, 95125 Catania, Italy.
Life Sci. 2012 Jun 27;90(25-26):968-74. doi: 10.1016/j.lfs.2012.04.043. Epub 2012 May 24.
The present work evaluated the anti-inflammatory/antioxidant activity of a well characterized extract from Citrus bergamia Risso and Poiteau (CBE), containing neoeriocitrin, naringin, neohesperidin and other flavonoids, on human NCTC 2544 keratinocytes treated with interferon-gamma (IFN-γ) and histamine (H).
High performance liquid chromatography (HPLC) coupled with diode array detectors was used to characterize and quantify phenolic compounds in CBE. Anti-inflammatory/antioxidant ability on keratinocytes was determined through evaluation of inter-cellular adhesion molecule-1 (ICAM-1) and inducible nitric oxide synthase (iNOS) expression by Western blot, production of nitric oxide (NO) with Griess reagent and concentration of reactive oxygen species (ROS) by fluorescent quantitative analysis with 2',7'-dichlorfluorescein-diacetate (DCFH-DA). Cell viability was assessed using 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Antioxidant activity was also measured by oxygen radical absorbance capacity (ORAC) assay. Glycosaminoglycans (GAGs) were quantified using 1.9-dimethyl methylene blue (DMB).
CBE exhibited high antioxidant activity confirmed by elevated ORAC values related to high capacity in oxygen radical scavenging. The assays on keratinocytes demonstrated that CBE does not inhibit cell proliferation and is shown to significantly reduce dose-dependently ICAM-1, iNOS, NO, ROS and GAG production in cells exposed to IFN-γ and H.
Our study demonstrates that the pools of compounds of an extract from C. bergamia efficiently block the proinflammatory actions induced by IFN-γ and H on human keratinocytes. CBE may be used for topic employment in some inflammatory diseases of the skin and to represent an important opportunity for the essential oil processing industries.
本研究评估了具有良好特征的柑橘属 Bergamia 里索和波托提取物（CBE）的抗炎/抗氧化活性，该提取物含有新橙皮苷、柚皮苷、新橙皮苷和其他类黄酮，对干扰素-γ（IFN-γ）和组胺（H）处理的人 NCTC 2544 角质形成细胞的作用。
高效液相色谱法（HPLC）与二极管阵列检测器联用，用于鉴定和定量 CBE 中的酚类化合物。通过 Western blot 评估细胞间黏附分子-1（ICAM-1）和诱导型一氧化氮合酶（iNOS）的表达，用 Griess 试剂测定一氧化氮（NO）的产生，用荧光定量分析 2',7'-二氯荧光素二乙酸酯（DCFH-DA）测定活性氧（ROS）的浓度，来评估角质形成细胞的抗炎/抗氧化能力。使用 3-(4,5-二甲基-2 噻唑基)-2,5-二苯基-2H-四唑溴盐（MTT）法评估细胞活力。通过氧自由基吸收能力（ORAC）测定法也测定了抗氧化活性。使用 1,9-二甲基甲亚胺蓝（DMB）定量测定糖胺聚糖（GAGs）。
CBE 表现出较高的抗氧化活性，这一点得到了确认，其 ORAC 值升高与氧自由基清除能力较高有关。对角质形成细胞的检测表明，CBE 不抑制细胞增殖，并能显著降低 IFN-γ 和 H 暴露细胞中 ICAM-1、iNOS、NO、ROS 和 GAG 的产生，呈剂量依赖性。
我们的研究表明，来自 C. bergamia 的提取物中的化合物库可以有效地阻止 IFN-γ 和 H 对人角质形成细胞的促炎作用。CBE 可用于治疗某些皮肤炎症性疾病，并为精油加工业提供重要机会。
