Kolodziejczyk-Czepas Joanna, Krzyżanowska-Kowalczyk Justyna, Sieradzka Malgorzata, Nowak Pawel, Stochmal Anna
Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland.
Phytochemistry. 2017 Nov;143:54-63. doi: 10.1016/j.phytochem.2017.07.011. Epub 2017 Aug 1.
This in vitro study provides a new insight into the phytochemical, antioxidant, antiplatelet and cytotoxic profiles of commercial trans-clovamide and clovamide-rich extracts, isolated from aerial parts of three Trifolium species (i.e. T. clypeatum L., T. obscurum Savi and T. squarrosum L.). Under inorganic experimental conditions, the EC for the investigated substances varied between 4.87 (clovamide) and 7.91 μg/ml (T. clypeatum) according to the DPPH assay. The most effective 1 mM ONOO scavenger was clovamide (IC = 19.29 μg/ml), and the weakest was the T. obsucurum extract (IC = 41.79 μg/ml). The antioxidant action of the examined substances (1-50 μg/ml) was also evaluated in blood plasma (under 100 μM ONOO-induced oxidative stress) using 3-nitrotyrosine, protein thiol groups, lipid hydroperoxides and thiobarbituric acid-reactive substances as biomarkers. All examined substances were more effective in limiting the oxidative damage to blood plasma components than the nitrative damage. Their anti-nitrative action was statistically significant only at the highest concentration (50 μg/ml). Measurements of platelet adhesion and aggregation found the compounds to have moderate antiplatelet properties of up to 20% inhibition of platelet adhesion at concentrations of 1-5 μg/ml. Additionally, clovamide and Trifolium extracts demonstrated no cytotoxicity towards blood platelets or peripheral blood mononuclear cells.
这项体外研究为从三种三叶草属植物（即密被三叶草、暗黄三叶草和疏花三叶草）地上部分分离得到的商业反式丁香酰胺和富含丁香酰胺的提取物的植物化学、抗氧化、抗血小板和细胞毒性特征提供了新的见解。在无机实验条件下，根据DPPH测定法，所研究物质的半数有效浓度（EC）在4.87（丁香酰胺）至7.91μg/ml（密被三叶草）之间变化。最有效的1mM过氧亚硝酸盐清除剂是丁香酰胺（半数抑制浓度[IC]=19.29μg/ml），最弱的是暗黄三叶草提取物（IC=41.79μg/ml）。还使用3-硝基酪氨酸、蛋白质硫醇基团、脂质氢过氧化物和硫代巴比妥酸反应性物质作为生物标志物，在血浆中（在100μM过氧亚硝酸盐诱导的氧化应激下）评估了所检测物质（1-50μg/ml）的抗氧化作用。所有检测物质在限制对血浆成分的氧化损伤方面比硝化损伤更有效。它们的抗硝化作用仅在最高浓度（50μg/ml）时具有统计学意义。血小板粘附和聚集的测量发现，这些化合物具有中等抗血小板特性，在1-5μg/ml浓度下对血小板粘附的抑制率高达20%。此外，丁香酰胺和三叶草提取物对血小板或外周血单核细胞没有细胞毒性。
