Circadian Rhythm of Metabolic Oscillation in Suprachiasmatic Nucleus Depends on the Mitochondrial Oxidation State, Reflected by Cytochrome C Oxidase and Lactate Dehydrogenase
Circadian Rhythm of Metabolic Oscillation in Suprachiasmatic Nucleus Depends on the Mitochondrial Oxidation State, Reflected by Cytochrome C Oxidase and Lactate Dehydrogenase
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DOI：
10.1002/jnr.22609
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发表时间：
2011-06-01
影响因子：
4.2
通讯作者：
Nishino, Hitoo
中科院分区：
文献类型：
--
作者：
Isobe, Yoshiaki;Hida, Hideki;Nishino, Hitoo
视交叉上核（SCN）是生物节律的中心，其代谢活动在白天比夜间高。SCN中的节律性振荡是由Clock/Bmal 1异二聚体与靶基因中的E-box结合的反馈控制的（例如，例如，在一个实施例中，精氨酸-加压素）。通过Npas 2/Bmal 1异二聚体形成的类似转录调节在脑中起作用，这取决于氧化还原状态（即，NAD/NADH）。为了阐明SCN的代谢功能与氧化还原状态和糖酵解水平的关系，我们测量了葡萄糖，乳酸脱氢酶（LDH），LDH mRNA，和细胞色素C氧化酶，能量产生的生化材料从线粒体/胞质溶胶，在大鼠保持在一个光暗循环。线粒体细胞色素C氧化酶的活性，测定在550 nm处的吸收的变化，在光周期比在黑暗时期。葡萄糖浓度在光照期间较高。相反，LDH及其编码mRNA在黑暗期较高。线粒体聚集，这是反映了线粒体膜电位，JC-1荧光指数，在光周期较高。结果表明，SCN中的糖酵解能量途径在白天比晚上表现出更高的代谢活性，可能参与了昼夜节律的产生。(C)2011 Wiley-Liss，Inc.
Metabolic activity in the suprachiasmatic nucleus (SCN), a center of biological rhythm, is higher during the daytime than at night. The rhythmic oscillation in the SCN is feedback controlled by the Clock/Bmal1 heterodimer binding to the E-box in target genes (e. g., Arg-vasopressin). Similar transcriptional regulation by Npas2/Bmal1 heterodimer formation operates in the brain, which is dependent on the redox state (i.e., NAD/NADH). To clarify the metabolic function of SCN in relation to the redox state and glycolysis levels, we measured glucose, lactate dehydrogenase (LDH), LDH mRNA, and cytochrome C oxidase, energy-producing biochemical materials from mitochondria/cytosol, in rats kept under a light-dark cycle. Mitochondrial cytochrome C oxidase activity, measured by the changes in absorption at 550 nm, was higher during the light period than during the dark period. Glucose concentration was higher during the light period. In contrast, LDH and its coding mRNA were higher during the dark period. Mitochondrial aggregation, which is reflected by mitochondrial membrane potential, indexed by JC-1 fluorescence, was higher during the light period. The results indicate that the glycolysis energy pathway in the SCN, which exhits higher metabolic activity during the day than at night, might be involved in the generation of circadian rhythm. (C) 2011 Wiley-Liss, Inc.