Wu Danli, Yotnda Patricia
Center for Cell and Gene Therapy, Baylor College of Medicine, USA.
J Vis Exp. 2011 Nov 21(57):3357. doi: 10.3791/3357.
Reactive oxygen species include a number of molecules that damage DNA and RNA and oxidize proteins and lipids (lipid peroxydation). These reactive molecules contain an oxygen and include H(2;)O(2;) (hydrogen peroxide), NO (nitric oxide), O(2;)(-) (oxide anion), peroxynitrite (ONOO(-)), hydrochlorous acid (HOCl), and hydroxyl radical (OH(-)). Oxidative species are produced not only under pathological situations (cancers, ischemic/reperfusion, neurologic and cardiovascular pathologies, infectious diseases, inflammatory diseases, autoimmune diseases , etc…) but also during physiological (non-pathological) situations such as cellular metabolism. Indeed, ROS play important roles in many cellular signaling pathways (proliferation, cell activation, migration etc..). ROS can be detrimental (it is then referred to as "oxidative and nitrosative stress") when produced in high amounts in the intracellular compartments and cells generally respond to ROS by upregulating antioxidants such as superoxide dismutase (SOD) and catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH) that protects them by converting dangerous free radicals to harmless molecules (i.e. water). Vitamins C and E have also been described as ROS scavengers (antioxidants). Free radicals are beneficial in low amounts. Macrophage and neutrophils-mediated immune responses involve the production and release of NO, which inhibits viruses, pathogens and tumor proliferation. NO also reacts with other ROS and thus, also has a role as a detoxifier (ROS scavenger). Finally NO acts on vessels to regulate blood flow which is important for the adaptation of muscle to prolonged exercise. Several publications have also demonstrated that ROS are involved in insulin sensitivity. Numerous methods to evaluate ROS production are available. In this article we propose several simple, fast, and affordable assays; these assays have been validated by many publications and are routinely used to detect ROS or its effects in mammalian cells. While some of these assays detect multiple ROS, others detect only a single ROS.
活性氧包括多种会损害DNA和RNA并氧化蛋白质和脂质（脂质过氧化）的分子。这些活性分子含有氧，包括H₂O₂（过氧化氢）、NO（一氧化氮）、O₂⁻（超氧阴离子）、过氧亚硝酸盐（ONOO⁻）、次氯酸（HOCl）和羟基自由基（OH⁻）。氧化物质不仅在病理情况下（癌症、缺血/再灌注、神经和心血管疾病、传染病、炎症性疾病、自身免疫性疾病等）产生，也在诸如细胞代谢等生理（非病理）情况下产生。事实上，活性氧在许多细胞信号通路（增殖、细胞活化、迁移等）中发挥重要作用。当在细胞内区室中大量产生时，活性氧可能有害（此时称为“氧化和亚硝化应激”），细胞通常通过上调抗氧化剂如超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）和谷胱甘肽（GSH）来应对活性氧，这些抗氧化剂通过将危险自由基转化为无害分子（即水）来保护细胞。维生素C和E也被描述为活性氧清除剂（抗氧化剂）。少量自由基是有益的。巨噬细胞和中性粒细胞介导的免疫反应涉及一氧化氮的产生和释放，一氧化氮可抑制病毒、病原体和肿瘤增殖。一氧化氮还与其他活性氧反应，因此也具有解毒剂（活性氧清除剂）的作用。最后，一氧化氮作用于血管以调节血流，这对于肌肉适应长时间运动很重要。一些出版物还证明活性氧与胰岛素敏感性有关。有多种评估活性氧产生的方法。在本文中，我们提出了几种简单、快速且经济实惠的检测方法；这些检测方法已被许多出版物验证，并经常用于检测哺乳动物细胞中的活性氧或其作用。虽然其中一些检测方法可检测多种活性氧，但其他方法仅检测单一活性氧。
