Center for Oxygen Research and Development, Institute of Chemistry B6a, University of Liège, 4000 Liège, Belgium; Department of Clinical Sciences, Equine Clinic, Veterinary Institute B41, University of Liège, 4000 Liège, Belgium.
Chem Biol Interact. 2013 Nov 25;206(2):194-203. doi: 10.1016/j.cbi.2013.09.009. Epub 2013 Sep 21.
We investigated the antioxidant activities of some phenolic acid derivatives on a cell free system and on cellular and enzymatic models involved in inflammation. The stoichiometric antioxidant activities of phenolic acid derivatives were studied by measuring their capacity to scavenge the radical cation 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS(+)) and reactive oxygen species (ROS) produced by stimulated neutrophils. The anticatalytic antioxidant capacity of the molecules was evaluated on the activity of myeloperoxidase (MPO), an oxidant enzyme present in and released by the primary granules of neutrophils. The ROS produced by PMA-stimulated neutrophils were measured by lucigenin-enhanced chemiluminescence (CL) and the potential interaction of the molecules with MPO was investigated without interferences due to medium by Specific Immuno-Extraction Followed by Enzyme Detection (SIEFED). The antioxidant activities of the phenolic compounds were correlated to their redox potentials measured by differential pulse voltammetry (DPV), and discussed in relation to their molecular structure. The ability of the phenolic molecules to scavenge ABTS radicals and ROS derived from neutrophils was inversely correlated to their increased redox potential. The number of hydroxyl groups (three) and their position (catechol) were essential for their efficacy as stoichiometric antioxidants or scavengers. On MPO activity, the inhibitory capacity of the molecules was not really correlated with their redox potential. Likewise, for the inhibition of MPO activity the number of OH groups and mainly the elongation of the carboxylic group were essential, probably by facilitating the interaction with the active site or the structure of the enzyme. The redox potential measurement, combined with ABTS and CL techniques, seems to be a good technique to select stoichiometric antioxidants but not anticatalytic ones, as seen for MPO, what rather involves a direct interaction with the enzyme.
我们研究了一些酚酸衍生物在无细胞体系以及细胞和酶模型中对炎症相关的抗氧化活性。通过测量其清除自由基阳离子 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）（ABTS(+)) 和由刺激的中性粒细胞产生的活性氧（ROS）的能力来研究酚酸衍生物的化学计量抗氧化活性。通过测量由 PMA 刺激的中性粒细胞产生的 ROS 来评估分子的抗催化抗氧化能力，髓过氧化物酶（MPO）是存在于和由中性粒细胞的初级颗粒释放的氧化酶。通过发光增强化学发光（CL）测量由 PMA 刺激的中性粒细胞产生的 ROS，并通过特异性免疫提取后酶检测（SIEFED）在没有介质干扰的情况下研究分子与 MPO 的潜在相互作用。通过差分脉冲伏安法（DPV）测量酚类化合物的氧化还原电位，并将其与分子结构相关联，讨论其抗氧化活性。酚类分子清除 ABTS 自由基和来自中性粒细胞的 ROS 的能力与其增加的氧化还原电位成反比。羟基的数量（三个）及其位置（儿茶酚）对于它们作为化学计量抗氧化剂或清除剂的功效是必不可少的。对于 MPO 活性，分子的抑制能力与其氧化还原电位没有真正相关。同样，对于 MPO 活性的抑制，羟基的数量和主要是羧酸基团的延长是必不可少的，可能通过促进与活性位点或酶结构的相互作用。氧化还原电位测量，结合 ABTS 和 CL 技术，似乎是一种很好的技术来选择化学计量抗氧化剂，但不是抗催化抗氧化剂，如 MPO 所见，这涉及到与酶的直接相互作用。
