Radical triads, not pairs, may explain effects of hypomagnetic fields on neurogenesis.
Radical triads, not pairs, may explain effects of hypomagnetic fields on neurogenesis.
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DOI：
10.1371/journal.pcbi.1010519
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发表时间：
2022-09
影响因子：
4.3
通讯作者：
中科院分区：
文献类型：
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成年小鼠海马神经发生和海马依赖性认知被发现受到低磁场暴露的不利影响。在没有地磁场的情况下，活性氧的减少也会产生这种效果。最近的一项理论研究提出了一个机械的解释，这一现象的框架下的自由基对机制。根据这个模型，黄素-超氧自由基对，出生在单重态自旋配置，经历磁场依赖的自旋动力学，使对的重组增强所施加的磁场减少。这个模型有两个明显的弱点：a）单重态初始状态的假设与产生这种自由基对的已知反应途径是不可调和的，以及B）该模型忽略了自由超氧化物的快速自旋弛豫，这消除了地磁/亚磁场中的任何磁敏感性。在这里，我们建议，一个模型的基础上的自由基三元组和二级自由基清除反应的假设，在原则上，可以解释的现象，没有不自然的假设，从而提供了一个连贯的解释亚磁场在生物学中的影响。大脑的海马区在学习和记忆功能中起着重要作用。在雄性小鼠中，发现屏蔽地球磁场会减少海马神经发生，即新神经元的形成，这是由于活性氧水平下降。在这项研究中，我们提出了一个解释的自旋动力学的三自由基系统组成的黄素半醌，超氧化物和抗坏血酸自由基。该模型与实验数据一致，同时保留了生物系统的现实参数，不像自由基对机制。
Adult hippocampal neurogenesis and hippocampus-dependent cognition in mice have been found to be adversely affected by hypomagnetic field exposure. The effect concurred with a reduction of reactive oxygen species in the absence of the geomagnetic field. A recent theoretical study suggests a mechanistic interpretation of this phenomenon in the framework of the Radical Pair Mechanism. According to this model, a flavin-superoxide radical pair, born in the singlet spin configuration, undergoes magnetic field-dependent spin dynamics such that the pair’s recombination is enhanced as the applied magnetic field is reduced. This model has two ostensible weaknesses: a) the assumption of a singlet initial state is irreconcilable with known reaction pathways generating such radical pairs, and b) the model neglects the swift spin relaxation of free superoxide, which abolishes any magnetic sensitivity in geomagnetic/hypomagnetic fields. We here suggest that a model based on a radical triad and the assumption of a secondary radical scavenging reaction can, in principle, explain the phenomenon without unnatural assumptions, thus providing a coherent explanation of hypomagnetic field effects in biology. The hippocampal region of the brain plays a major role in learning and memory functionality. In male mice, shielding of the Earth’s magnetic field was found to decrease hippocampal neurogenesis, i.e. the formation of new neurons, following from a decrease in levels of reactive oxygen species. In this study, we suggest an explanation in terms of spin dynamics of a three radical system composed of flavin-semiquinone, superoxide and ascorbyl radical. This model agrees with the experimental data whilst retaining realistic parameters for a biological system, unlike the Radical Pair Mechanism.
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影响因子：
--
作者：
CABELLI, DE;BIELSKI, BHJ
通讯作者：
BIELSKI, BHJ
影响因子：
21.8
作者：
Kattnig, Daniel R.;Evans, Emrys W.;Hore, P. J.
通讯作者：
Hore, P. J.
影响因子：
4.4
作者：
Atkins, Chadsley;Bajpai, Kieran;Kattnig, Daniel R.
通讯作者：
Kattnig, Daniel R.
DOI：
10.1073/pnas.1600341113
发表时间：
2016-04-26
影响因子：
11.1
作者：
Hiscock, Hamish G.;Worster, Susannah;Hore, P. J.
通讯作者：
Hore, P. J.
影响因子：
4.4
作者：
Fay, Thomas P.;Lindoy, Lachlan P.;Manolopoulos, David E.
通讯作者：
Manolopoulos, David E.