Petukh M G, Semenkova G N, Fuchs D, Cherenkevich S N
Tsitologiia. 2009;51(10):824-9.
We investigated the influence ofneopterin and 7, 8-dihydroneopterin on the activity and secretory degranulation of myeloperoxidase in neutrophils and the ability of pteridines to interact with the main substrate of this enzyme, hydrogen peroxide, and with the intermediate product of halogenation cycle--hypochlorous acid. It was shown that neopterin and 7, 8-dihydroneopterin while being a redox-pair regulated the process of oxygen activation in neutrophils by functioning of myeloperoxidase. Depending on concentration, pteridines can influence the secretion of myeloperoxidase into intracellular medium and decrease the level of hydrogen peroxide and hypochlorous acid that are a substrate and an intermediate product of the enzyme respectively. It was shown that 7, 8-dihydroneopterin in micromolar concentration appeared to be noncompetitive inhibitor of myeloperoxidase. We suppose that myeloperoxidase assists 7, 8-dihydroneopterin oxidation by hypochlorous acid that leads to neopterin concentration increase. These changes modify the concentration of reactive oxygen species in intracellular and extracellular media.
我们研究了新蝶呤和7,8 - 二氢新蝶呤对中性粒细胞中髓过氧化物酶活性和分泌性脱颗粒的影响，以及蝶啶与该酶的主要底物过氧化氢和卤化循环中间产物——次氯酸相互作用的能力。结果表明，新蝶呤和7,8 - 二氢新蝶呤作为氧化还原对，通过髓过氧化物酶的作用调节中性粒细胞中的氧激活过程。根据浓度不同，蝶啶可影响髓过氧化物酶向细胞内介质的分泌，并降低过氧化氢和次氯酸的水平，它们分别是该酶的底物和中间产物。结果表明，微摩尔浓度的7,8 - 二氢新蝶呤似乎是髓过氧化物酶的非竞争性抑制剂。我们推测髓过氧化物酶协助次氯酸氧化7,8 - 二氢新蝶呤，导致新蝶呤浓度增加。这些变化改变了细胞内和细胞外介质中活性氧的浓度。
