Testa Maria Pia, Alvarado Omar, Wournell Andrea, Lee Jonathan, Guilford Frederick T, Henriksen Steven H, Phillips Tom R
College of Veterinary Medicine, Western University of Health Sciences, USA.
J Vis Exp. 2011 Jul 13(53):e2841. doi: 10.3791/2841.
An often-suggested mechanism of virus induced neuronal damage is oxidative stress. Astrocytes have an important role in controlling oxidative stress of the Central Nervous System (CNS). Astrocytes help maintain a homeostatic environment for neurons as well as protecting neurons from Reactive Oxygen Species (ROS). CM-H2DCFDA is a cell-permeable indicator for the presence of ROS. CM-H(2)DCFDA enters the cell as a non-fluorescent compound, and becomes fluorescent after cellular esterases remove the acetate groups, and the compound is oxidized. The number of cells, measured by flow cytometry, that are found to be green fluorescing is an indication of the number of cells that are in an oxidative state. CM-H(2)DCFDA is susceptible to oxidation by a large number of different ROS. This lack of specificity, regarding which ROS can oxidize CM-H(2)DCFDA, makes this compound a valuable regent for use in the early stages of a pathogenesis investigation, as this assay can be used to screen for an oxidative cellular environment regardless of which oxygen radical or combination of ROS are responsible for the cellular conditions. Once it has been established that ROS are present by oxidation of CM-H(2)DCFDA, then additional experiments can be performed to determine which ROS or combination of ROSs are involved in the particular pathogenesis process. The results of this study demonstrate that with the addition of hydrogen peroxide an increase in CM-H(2)DCFDA fluorescence was detected relative to the saline controls, indicating that this assay is a valuable test for detecting an oxidative environment within G355-5 cells, a feline astrocyte cell line.
一种常被提及的病毒诱导神经元损伤机制是氧化应激。星形胶质细胞在控制中枢神经系统(CNS)的氧化应激中发挥着重要作用。星形胶质细胞有助于为神经元维持稳态环境,并保护神经元免受活性氧(ROS)的侵害。CM-H2DCFDA是一种用于检测ROS存在的细胞可渗透指示剂。CM-H(2)DCFDA以非荧光化合物的形式进入细胞,在细胞酯酶去除乙酰基并使该化合物被氧化后变为荧光性。通过流式细胞术测量发现呈绿色荧光的细胞数量可指示处于氧化状态的细胞数量。CM-H(2)DCFDA易被大量不同的ROS氧化。关于哪种ROS能氧化CM-H(2)DCFDA缺乏特异性,这使得该化合物成为发病机制研究早期阶段的一种有价值试剂,因为该检测方法可用于筛查氧化细胞环境,而不论哪种氧自由基或ROS组合导致细胞状况。一旦通过CM-H(2)DCFDA的氧化确定存在ROS,那么就可以进行额外实验以确定哪种ROS或ROS组合参与特定的发病过程。本研究结果表明,相对于生理盐水对照,添加过氧化氢后检测到CM-H(2)DCFDA荧光增加,这表明该检测方法对于检测猫星形胶质细胞系G355-5细胞内的氧化环境是一种有价值的测试。