Mechanisms underlying the aluminum-induced potentiation of the pro-oxidant properties of transition metals.
Mechanisms underlying the aluminum-induced potentiation of the pro-oxidant properties of transition metals.
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DOI：
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发表时间：
1998-02
期刊：
影响因子：
3.4
通讯作者：
S. Bondy;S. Guo-Ross;J. Pien
中科院分区：
文献类型：
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作者：
S. Bondy;S. Guo-Ross;J. Pien
众所周知，铝可以增强铁促进活性氧（ROS）生成的能力，但其机制尚不清楚。为了了解这种增强作用发生的方式，进行了几种类型的实验。研究发现，铁必须以亚铁形式存在，才能在大脑皮质突触体-线粒体部分中发生基于铝的 ROS 刺激。在铝的存在下，其他不同价态的过渡金属（铜和铬）催化ROS形成的能力也得到增强。过氧化氢酶而非超氧化物歧化酶阻断了这种刺激，表明过氧化氢是中间体。脑组织中硅铝酸盐的形成不会增强铁刺激的 ROS 形成。此外，为解释这种现象而提出的蛋白质构型变化似乎并不是关键因素，因为可以使用带有外部负电荷的无蛋白质脂质体胶束观察到铁-铝增强作用。
Aluminum is known to enhance the ability of iron to promote the generation of reactive oxygen species (ROS) but the mechanism subserving this is unknown. In an attempt to understand the means by which this potentiation occurs, several types of experiment have been conducted. It was found that iron must be in the ferrous form for aluminum-based stimulation of ROS to take place in a cerebral cortical synaptosomal-mitochondrial fraction. The ability of other transition metals of varying valences, copper and chromium, to catalyze formation of ROS was also increased in the presence of aluminum. Catalase but not superoxide dismutase blocked such stimulation suggesting hydrogen peroxide as an intermediate. The formation of aluminosilicates in the presence of brain tissue did not enhance iron-stimulated ROS formation. Furthermore, configurational changes of proteins which have been proposed to account for this phenomenon, do not appear to be a key element since iron-aluminum potentiation could be observed using protein-free liposomal micelles bearing an external negative charge.