Laboratoire de Photobiologie des Cancers, Département Laser, 44093, Nantes, France.
Photochem Photobiol Sci. 2009 Oct;8(10):1476-86. doi: 10.1039/b9pp00032a. Epub 2009 Aug 24.
Singlet oxygen (1O2) is produced by leucocytes during inflammatory reactions, various biochemical reactions and during photoreactions. It deactivates by reacting with a number of targets to produce reactive oxygen species (ROS) and peroxides (that in turn produce ROS). To verify whether serum had the same capability to deactivate secondary oxidants after exposure to 1O2, we provoked a photoreaction using rose bengal added to sera of 53 healthy donors and, after light delivery, reduced 2',7'-dichlorofluorescein (DCFH) was added at the end of irradiation and fluorescence of the oxidized derivative (DCF) was recorded. To avoid optical artifacts, we analyzed the influence of hemolysis. Deactivation capability of secondary oxidants after exposure to (1)O(2) was stable over a long period of time, slightly different between men and women, but standard biochemistry parameters had little influence. Hemolysis, age and platelet number reduced deactivation of 1O2-induced secondary oxidants. Addition of lysed cancer cells had no influence. Blood sampling in clot act tubes gave a better signal than in heparinized tubes. Red blood cells (RBCs) loaded with antioxidants strongly decreased deactivation of secondary oxidants. Assays are in progress to evaluate the clinical implications of these findings.
单线态氧（1O2）是由白细胞在炎症反应、各种生化反应和光反应中产生的。它通过与许多靶标反应失活，产生活性氧（ROS）和过氧化物（继而产生 ROS）。为了验证血清在暴露于 1O2 后是否具有相同的能力来使次级氧化剂失活，我们使用添加到 53 名健康供体血清中的孟加拉玫瑰红引发光反应，并且在光传递之后，在辐照结束时添加 2'，7'-二氯荧光素（DCFH），并记录氧化衍生物（DCF）的荧光。为了避免光学假象，我们分析了溶血的影响。暴露于（1）O（2）后次级氧化剂的失活能力在很长一段时间内是稳定的，在男性和女性之间略有不同，但标准生化参数的影响很小。溶血、年龄和血小板计数降低了 1O2 诱导的次级氧化剂的失活。添加裂解的癌细胞没有影响。在凝血试管中采集血液比在肝素化试管中采集血液产生的信号更好。用抗氧化剂负载的红细胞（RBC）强烈降低了次级氧化剂的失活。正在进行评估这些发现的临床意义的研究。
