亚甲蓝对心肺缺血再灌注线粒体损伤的保护作用及机制

发布时间：2018-11-07 16:58

【摘要】：亚甲蓝(methyleneblue,MB)是一种吩噻嗪盐,临床上用来治疗高铁血红蛋白血症及氰化物中毒等。现有研究表明,MB在线粒体中可以充当电子载体增强呼吸链功能。本研究利用过氧化氢(hydrogen peroxide,H202)刺激小鼠腹腔巨噬细胞株RAW264.7引发氧化应激,并建立大鼠离体心、肺缺血再灌注(ischemia-reperfusion,IR)损伤模型,研究MB对氧化应激损伤和IR损伤的保护作用及机制。在H202刺激RAW264.7诱发氧化应激的实验中,0.1 μM和1μM MB处理组细胞存活率升高,乳酸脱氢酶(lactate dehydrogenase, LDH)释放减少,反映MB能有效减轻细胞损伤;MB处理使H2O2刺激的RAW264.7中活性氧(reactive oxygen species, ROS)产生减少,超氧化物歧化酶(superoxydedismutase,SOD)活性增强;同时MB处理使线粒体膜电位(mitochondrial membrane potential, MMP)升高,三磷酸腺苷(adenosine triphosphate, ATP)生成增加,半胱天冬酶-3活化程度降低,细胞凋亡减少,表明MB有效增强线粒体功能、减少细胞凋亡。在大鼠离体心、肺IR实验中,大鼠手术前2 h以2 mg/kg剂量腹腔注射MB处理使IR损伤后的离体心、肺功能改善,病理学损伤减轻,LDH释放减少,提示MB有效减轻了 IR引起的器官损伤;同时与IR组相比,MB处理使组织中ROS及丙二醛(malondialdehyde,MDA)的产生减少,而SOD活性增强,说明MB能改善氧化应激;MB增加IR后心、肺组织中MMP和线粒体中ATP生成,减轻线粒体肿胀,反映出MB对线粒体功能发挥了保护作用。离体肺IR实验结果还表明,MB处理抑制IR损伤后细胞色素C由线粒体向细胞质中释放,使细胞凋亡减少。研究结果表明MB能减轻H202诱发的RAW264.7氧化应激损伤和IR诱发的大鼠离体心、肺损伤,其保护机制可能与其能维持呼吸链功能、减轻线粒体损伤有关。
[Abstract]:Methylene blue (methyleneblue,MB) is a phenothiazine, which is used to treat methemoglobin and cyanide poisoning. Existing studies have shown that MB can act as an electronic carrier to enhance respiratory chain function in mitochondria. In this study, oxidative stress was induced by hydrogen peroxide (hydrogen peroxide,H202) stimulation of mouse peritoneal macrophage line RAW264.7, and an isolated rat heart and lung ischemia-reperfusion (ischemia-reperfusion,IR) injury model was established. To study the protective effect and mechanism of MB on oxidative stress and IR injury. In the oxidative stress induced by RAW264.7 stimulated by H202, the survival rate increased and the (lactate dehydrogenase, LDH) release of lactate dehydrogenase decreased in 0.1 渭 M and 1 渭 M MB groups, indicating that MB could effectively reduce cell damage. MB treatment decreased the production of reactive oxygen (reactive oxygen species, ROS) and enhanced the activity of superoxide dismutase (superoxydedismutase,SOD) in RAW264.7 stimulated by H2O2. At the same time, MB treatment increased mitochondrial membrane potential (mitochondrial membrane potential, MMP), adenosine triphosphate (adenosine triphosphate, ATP) production, cysteinase-3 (caspase 3) activation and apoptosis, which indicated that MB could effectively enhance mitochondrial function. Reduce apoptosis. In the isolated heart and lung IR test, the isolated heart of rats was treated with 2 mg/kg intraperitoneal injection of MB 2 hours before operation, the lung function was improved, the pathological injury was alleviated, and the release of LDH was decreased. The results suggest that MB can effectively alleviate the organ damage induced by IR. At the same time, compared with IR group, MB treatment decreased the production of ROS and malondialdehyde (malondialdehyde,MDA), but increased the activity of SOD, indicating that MB could improve oxidative stress. MB increased the production of MMP and ATP in the lung and heart after IR, and alleviated the swelling of mitochondria, which indicated that MB played a protective role on mitochondrial function. The results of IR in vitro lung also showed that MB treatment inhibited cytochrome C release from mitochondria to cytoplasm and decreased apoptosis after IR damage. The results showed that MB could attenuate the oxidative stress of RAW264.7 induced by H202 and the injury of isolated rat heart and lung induced by IR. The protective mechanism of MB may be related to its ability to maintain the function of respiratory chain and alleviate the damage of mitochondria.
【学位授予单位】：江南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R96

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