Manganese: Brain transport and emerging research needs
Manganese: Brain transport and emerging research needs
复制标题
DOI：
10.2307/3454532
复制
发表时间：
2000-06-01
影响因子：
10.4
通讯作者：
Aschner, M
中科院分区：
文献类型：
--
作者：
Aschner, M
特发性帕金森病（IPD）是一种常见的神经退行性疾病。据估计，65岁及以上的美国人口中有2%患有IPD。随着婴儿潮一代逐渐步入这个高危年龄组，随着平均预期寿命的增加，IPD患者的数量肯定会在未来几十年内增加。虽然许多研究表明工业化学品和农药可能是[PD]的基础，但其病因仍然难以捉摸。在有毒金属中，锰中毒与IPD的关系早已被认识。锰中毒的神经系统体征受到密切关注，因为它们类似于统称为锥体外系运动系统功能障碍的几种临床疾病，特别是IPD和肌张力障碍。然而，IPD和锰中毒之间的明显差异是公认的，它仍然有待确定锰是否在IPD中发挥病因作用。特别值得注意的是，由于最近的法院判决，甲基三羰基锰（MMT）目前在美国和加拿大可用于燃料，取代铅作为抗爆添加剂。潜在长期暴露于可能存在于汽车排放物中的低水平MMT燃烧产物的影响尚未得到充分评估。然而，应该指出的是，最近在蒙特利尔大都市（MMT已经使用了10多年）采用各种环境建模方法进行的研究表明，空气中的Mn含量与未使用MMT的地区非常相似。这些研究还表明，锰主要以磷酸锰和硫酸锰的混合物的形式从机动车辆的尾管排放。这篇简短的综述描述了锰在血液中的形态和锰进入中枢神经系统的转运动力学，这是锰在脑内积累的关键步骤，概述了选定人群的潜在易感性（例如，缺铁）锰暴露，并解决未来的研究需要锰。
Idiopathic Parkinson's disease (IPD) represents a common neurodegenerative disorder. An estimated 2% of the U.S. population, age 65 and older, develops IPD. The number of IPD patients will certainly increase over the next several decades as the baby-boomers gradually step into this high-risk age group, concomitant with the increase in the average life expectancy. While many studies have suggested that industrial chemicals and pesticides may underlie [PD, its etiology remains elusive. Among the toxic metals, the relationship between manganese intoxication and IPD has long been recognized. The neurological signs of manganism have received close attention because they resemble several clinical disorders collectively described as extrapyramidal motor system dysfunction, and in particular, IPD and dystonia. However, distinct dissimilarities between IPD and manganism are well established, and it remains to be determined whether Mn plays an etiologic role in IPD. It is particularly noteworthy that as a result of a recent court decision, methylcyclopentadienyl Mn tricarbonyl (MMT) is presently available in the United States and Canada for use in fuel, replacing lead as an antiknock additive. The impact of potential long-term exposure to low levels of MMT combustion products that may be present in emissions from automobiles has yet to be fully evaluated. Nevertheless, it should be pointed out that recent studies with Various environmental modeling approaches in the Montreal metropolitan (where MMT has been used for more than 10 years) suggest that airborne Mn revels were quite similar to those in areas where MMT was not used. These studies also show that Mn is emitted from the tail pipe of motor vehicles primarily as a mixture of manganese phosphate and manganese sulfate. This brief review characterizes the Mn speciation in the blood and the transport kinetics of Mn into the central nervous system, a critical step in the accumulation of Mn within the brain, outlines the potential susceptibility of selected populations (e.g., iron-deficient) to Mn exposure, and addresses future research needs for Mn.