Gureev Artem P, Shaforostova Ekaterina A, Laver Denis A, Khorolskaya Victoria G, Syromyatnikov Mikhail Yu, Popov Vasily N
Voronezh State University, Faculty of Medicine and Biology, Department of Genetics, Cytology and Bioengineering, Voronezh, Russia.
Voronezh State University of Engineering Technologies, Voronezh, Russia.
J Appl Biomed. 2019 Jun;17(2):107-114. doi: 10.32725/jab.2019.008. Epub 2019 Jun 17.
Methylene blue (MB) is a promising compound with a broad range of neuroprotective activity. One of therapeutic effects is the activation of mitochondrial biogenesis via Nrf2/ARE signaling cascade. Probably, mild oxidative stress caused by MB-depended H2O2 production is a trigger for activation of this signaling cascade. So mechanistically, MB can be regarded as prooxidant. We investigated the dose-dependent H2O2 production in intact brain mitochondria and showed the increase in the H2O2 production after adding as little as 50 nM MB. We have not found genotoxic effect of therapeutic concentration of MB to mitochondrial genome. 100 μM MB selectively damaged fragments of mitochondrial DNA, which correlated with the number of purine-T-G-purine (RTGR)-sequences in studied fragments. Furthermore, 20 μM MB combined with the red light caused the formation of singlet oxygen, which strongly damaged mitochondrial DNA in all studied fragments. We did not observe mitochondrial DNA lesions in brain after single intraperitoneal injection of MB in the concentration of 50 mg/kg. Furthermore, we showed the neuroprotective properties of MB pretreatments after rotenone injection. Therefore, we suggest that MB-induced mild oxidative stress does not have genotoxic effect on mitochondrial DNA.
亚甲蓝（MB）是一种具有广泛神经保护活性的有前景的化合物。其治疗作用之一是通过Nrf2/ARE信号级联激活线粒体生物合成。可能，由MB依赖的H2O2产生引起的轻度氧化应激是激活该信号级联的触发因素。因此，从机制上讲，MB可被视为促氧化剂。我们研究了完整脑线粒体中剂量依赖性的H2O2产生，并表明加入低至50 nM的MB后H2O2产生增加。我们未发现治疗浓度的MB对线粒体基因组有遗传毒性作用。100 μM的MB选择性地损伤线粒体DNA片段，这与所研究片段中嘌呤-T-G-嘌呤（RTGR）序列的数量相关。此外，20 μM的MB与红光结合会导致单线态氧的形成，这会强烈损伤所有研究片段中的线粒体DNA。在单次腹腔注射50 mg/kg浓度的MB后，我们未在脑中观察到线粒体DNA损伤。此外，我们展示了鱼藤酮注射后MB预处理的神经保护特性。因此，我们认为MB诱导的轻度氧化应激对线粒体DNA没有遗传毒性作用。
