Yoshida S
Division of Neurological Diseases, Wakayama Medical College.
Rinsho Shinkeigaku. 1991 Dec;31(12):1310-2.
Recent decline in incidence rates of ALS in Guam and the Kii Peninsula of Japan strongly implicates environmental factors rather than inheritance in its causation. Environmental studies in Western Pacific foci showed identical mineral compositions in the soils and drinking water, i.e., extremely low calcium (Ca) and magnesium (Mg) and high aluminum (Al) and manganese (Mn). Series of trace-elemental analyses of the CNS tissue of ALS patients have revealed a high contents of Al and Ca with significant positive correlations between Al and Ca and/or between Ca and Mn, suggesting the prolonged exposure to these trace environment to cause abnormal mineral metabolism detrimental to neurons. Using electron energy loss spectrometry (EELS), Al was found to accumulate within DNA-containing chromatins and rRNA-containing cellular components, i.e., nucleolus, heterochromatin, rough endoplasmic reticulum, in lumbar motor neurons of ALS. Thus, Al may preferentially bind to nucleic acids and cause a progressive inhibition of the protein synthesis of rRNA and the transcription or gene modulation of DNA, leading to neuronal degeneration.
关岛和日本纪伊半岛肌萎缩侧索硬化症（ALS）发病率近期的下降强烈表明，其病因是环境因素而非遗传因素。对西太平洋发病地区的环境研究表明，土壤和饮用水中的矿物质成分相同，即钙（Ca）和镁（Mg）含量极低，而铝（Al）和锰（Mn）含量很高。对ALS患者中枢神经系统组织进行的一系列微量元素分析显示，铝和钙含量很高，且铝与钙之间和/或钙与锰之间存在显著正相关，这表明长期暴露于这些微量环境会导致不利于神经元的异常矿物质代谢。使用电子能量损失谱（EELS）发现，铝在ALS患者腰段运动神经元中含DNA的染色质和含rRNA的细胞成分（即核仁、异染色质、粗面内质网）中积累。因此，铝可能优先与核酸结合，并导致rRNA蛋白质合成以及DNA转录或基因调控的逐步抑制，从而导致神经元变性。
