Distinct differences in rates of oxygen consumption and ATP synthesis of regionally isolated non-synaptic mouse brain mitochondria
Distinct differences in rates of oxygen consumption and ATP synthesis of regionally isolated non-synaptic mouse brain mitochondria
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DOI：
10.1002/jnr.24371
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发表时间：
2019-08-01
影响因子：
4.2
通讯作者：
Aldana, Blanca I.
中科院分区：
文献类型：
--
作者：
Andersen, Jens V.;Jakobsen, Emil;Aldana, Blanca I.
脑线粒体功能障碍与几种神经退行性疾病有关。线粒体的分布和效率在整个大脑区域显示出很大的异质性。这可能意味着神经退行性疾病的选择性区域易感性可以通过区域线粒体功能的固有差异来介导。为了研究局部脑线粒体能量学，在雄性小鼠脑的大脑皮层、海马和纹状体的分离的非突触线粒体中评估氧消耗和腺苷-5 '-三磷酸（ATP）合成的速率。使用Seahorse XFe 96分析仪评估氧消耗速率，并通过在线的荧光素酶偶联发光测定法确定ATP合成速率。复合物I和复合物II驱动的呼吸和ATP合成，分别通过应用丙酮酸与苹果酸或琥珀酸作为呼吸底物进行了研究。当提供丙酮酸和苹果酸时，海马线粒体表现出最低的基础和腺苷-5 '-二磷酸（ADP）刺激的耗氧速率。然而，海马线粒体也表现出增加的质子泄漏和升高的相对速率的氧消耗在响应解偶联剂羰基氰4-（三氟甲氧基）苯腙（FCCP），显示出大容量的解偶联呼吸丙酮酸的存在下。当提供复合物II连接的底物琥珀酸时，纹状体线粒体的呼吸和ATP合成速率最高，而海马线粒体的最低。然而，线粒体效率，确定为ATP产生/O-2消耗，是三个区域之间的相似。这项研究揭示了区域线粒体能量学的内在差异，并可能作为进一步研究区域线粒体功能与神经退行性疾病的工具。
Brain mitochondrial dysfunction has been implicated in several neurodegenerative diseases. The distribution and efficiency of mitochondria display large heterogeneity throughout the regions of the brain. This may imply that the selective regional susceptibility of neurodegenerative diseases could be mediated through inherent differences in regional mitochondrial function. To investigate regional cerebral mitochondrial energetics, the rates of oxygen consumption and adenosine-5 '-triphosphate (ATP) synthesis were assessed in isolated non-synaptic mitochondria of the cerebral cortex, hippocampus, and striatum of the male mouse brain. Oxygen consumption rates were assessed using a Seahorse XFe96 analyzer and ATP synthesis rates were determined by an online luciferin-luciferase coupled luminescence assay. Complex I- and complex II-driven respiration and ATP synthesis, were investigated by applying pyruvate in combination with malate, or succinate, as respiratory substrates, respectively. Hippocampal mitochondria exhibited the lowest basal and adenosine-5 '-diphosphate (ADP)-stimulated rate of oxygen consumption when provided pyruvate and malate. However, hippocampal mitochondria also exhibited an increased proton leak and an elevated relative rate of oxygen consumption in response to the uncoupler carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), showing a large capacity for uncoupled respiration in the presence of pyruvate. When the complex II-linked substrate succinate was provided, striatal mitochondria exhibited the highest respiration and ATP synthesis rate, whereas hippocampal mitochondria had the lowest. However, the mitochondrial efficiency, determined as ATP produced/O-2 consumed, was similar between the three regions. This study reveals inherent differences in regional mitochondrial energetics and may serve as a tool for further investigations of regional mitochondrial function in relation to neurodegenerative diseases.