Alzheimer’s disease (AD) is the main cause of dementia in elderly. Increasing life expectancy is behind the growing prevalence of AD worldwide with approximately 45 million cases currently documented and projection studies suggesting a triplication of this number by 2050. Mexico does not have an accurate AD registry, but 860,000 cases were reported in 2014 and the prediction reaches 3.5 million cases by 2050. Amyloid plaques and neurofibrillary tangles represent the main hallmarks of AD, being constituted of amyloid beta (Aβ) peptide and phosphorylated tau, respectively. The risk factors for AD include genetic mutations, lifestyle and environmental pollution. Particularly, lead (Pb) has attracted attention due to its ability to target multiple pathways involved in the pathophysiology of AD. Although the epidemiological data are limiting, animal and in vitro studies show growing evidence of causal effects of Pb exposure on AD-linked features including Aβ aggregation and tau phosphorylation. Interestingly, many Pb effects occur selectively following early-life exposure to the metal, suggesting an epigenetic mechanism. This hypothesis is supported by changes in DNA methylation and microRNA expression patterns inflicted by early-life Pb exposure. Pb pollution in Mexico represents a significant problem because past and current mining activities, historical use of Pb as fuel additive and culturally rooted use of Pb in glazed ceramics, contribute to high levels of Pb pollution in Mexico. In this review we will discuss potential risks of AD development in Mexican populations chronically exposed to Pb in their childhood.

中文翻译：

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铅早期暴露是阿尔茨海默氏病的潜在危险因素：墨西哥人口是否有危害？

阿尔茨海默氏病（AD）是老年人痴呆症的主要原因。预期寿命的增加是全球AD流行率上升的原因，目前有大约4,500万例病例记录在案，而预测研究表明，到2050年，这一数字将增加三倍。墨西哥尚无准确的AD登记册，但2014年报告了860,000例，且预测达到到2050年将达到350万例。淀粉样蛋白斑块和神经原纤维缠结是AD的主要标志，分别由淀粉样蛋白β（Aβ）肽和磷酸化的tau构成。AD的危险因素包括基因突变，生活方式和环境污染。特别地，铅（Pb）由于其靶向多种与AD病理生理学有关的途径的能力而引起了人们的关注。尽管流行病学数据有限，动物和体外研究表明，铅暴露对AD相关特征（包括Aβ聚集和tau磷酸化）的因果关系的证据越来越多。有趣的是，在生命早期暴露于金属后，有选择地发生了许多Pb效应，表明了表观遗传机制。早年Pb暴露引起的DNA甲基化和microRNA表达模式的变化支持了这一假设。墨西哥的铅污染是一个严重的问题，因为过去和现在的采矿活动，铅在燃料陶瓷中的历史使用以及铅在陶瓷上的根源在文化上都造成了墨西哥高水平的铅污染。在这篇综述中，我们将讨论在儿童期长期暴露于铅的墨西哥人群中AD发展的潜在风险。