Cuzzocrea S, Caputi A P, Zingarelli B
Institute of Pharmacology, School of Medicine, University of Messina, Italy.
Immunology. 1998 Jan;93(1):96-101. doi: 10.1046/j.1365-2567.1998.00409.x.
The aim of the present study was to investigate the role of poly (ADP-ribose) synthetase in acute local inflammation (carrageenan-induced pleurisy), where oxyradicals, nitric oxide and peroxynitrite are known to play a crucial role in the inflammatory process. DNA single-strand breakage and activation of the nuclear enzyme poly (ADP-ribose) synthetase (PARS) triggers an energy-consuming, inefficient repair cycle, which contributes to peroxynitrite-induced cellular injury. Here we investigated whether peroxynitrite production and PARS activation are involved in cytotoxicity in macrophages collected from rats subjected to carrageenan-induced pleurisy. Macrophages harvested from the pleural cavity exhibited a significant production of peroxynitrite, as measured by the oxidation of the fluorescent dye dihydrorhodamine 123, and by nitrotyrosine Western blotting at 4 hr after carrageenan injection. Furthermore, carrageenan-induced pleurisy caused a suppression of macrophage mitochondrial respiration, DNA strand breakage, activation of PARS and reduction of NAD+ cellular levels. In vivo treatment with 3-aminobenzamide (10 mg/kg intraperitoneally, 1 hr after carrageenin injection) significantly inhibited the decrease in mitochondrial respiration and the activation of PARS and partially restored the cellular level of NAD+. In a separate group of experiments, in vivo pretreatment with NG-nitro-L-arginine methyl ester, a non-selective inhibitor of nitric oxide (NO) synthesis (10 mg/kg intraperitoneally, 15 min before carrageenan administration), reduced peroxynitrite formation and prevented the appearance of DNA damage, the decrease in mitochondrial respiration and the loss of cellular levels of NAD+. Our study suggests that formation of peroxynitrite and subsequent activation of PARS may alter macrophage function in inflammatory processes and inhibition of NO and PARS may be a novel pharmacological approach to prevent cell injury in inflammation.
本研究的目的是探讨聚（ADP - 核糖）合成酶在急性局部炎症（角叉菜胶诱导的胸膜炎）中的作用，已知氧自由基、一氧化氮和过氧亚硝酸盐在炎症过程中起关键作用。DNA单链断裂和核酶聚（ADP - 核糖）合成酶（PARS）的激活触发了一个耗能的、低效的修复循环，这导致了过氧亚硝酸盐诱导的细胞损伤。在此，我们研究了过氧亚硝酸盐的产生和PARS的激活是否参与了从角叉菜胶诱导的胸膜炎大鼠中收集的巨噬细胞的细胞毒性。通过荧光染料二氢罗丹明123的氧化以及角叉菜胶注射后4小时的硝基酪氨酸免疫印迹法测定，从胸腔收集的巨噬细胞显示出过氧亚硝酸盐的大量产生。此外，角叉菜胶诱导的胸膜炎导致巨噬细胞线粒体呼吸抑制、DNA链断裂、PARS激活以及细胞内NAD +水平降低。在角叉菜胶注射后1小时腹腔注射3 - 氨基苯甲酰胺（10 mg/kg）进行体内治疗，显著抑制了线粒体呼吸的降低和PARS的激活，并部分恢复了细胞内NAD +水平。在另一组实验中，用一氧化氮（NO）合成的非选择性抑制剂NG - 硝基 - L - 精氨酸甲酯（在角叉菜胶给药前15分钟腹腔注射10 mg/kg）进行体内预处理，减少了过氧亚硝酸盐的形成，并防止了DNA损伤的出现、线粒体呼吸的降低以及细胞内NAD +水平的损失。我们的研究表明，过氧亚硝酸盐的形成以及随后PARS的激活可能会改变炎症过程中巨噬细胞的功能，抑制NO和PARS可能是预防炎症中细胞损伤的一种新的药理学方法。
