第2117期:Study Details Brain Changes in Alzheimer’s Patients

A long-term study in China has shown that a series of changes take place in the brains of people who get Alzheimer’s disease long before they present signs of the sickness.

中国的一项长期研究表明，早在阿尔茨海默病患者出现症状之前，他们的大脑就发生了一系列变化。

The large study followed middle-aged and older adults for 20 years. The individuals were examined on a regular basis during that period. The researchers used brain imaging, spinal fluid checks and other tools to collect data.

这项大型研究对中老年人进行了长达 20 年的跟踪调查。 在此期间，这些人定期接受检查。 研究人员使用脑成像、脊髓液检查和其他工具来收集数据。

The researchers reported that the study subjects who later developed Alzheimer’s showed high levels of disease-linked protein in their spinal fluid. The higher levels were recorded as much as 18 years before the patients were identified as having Alzheimer's.

研究人员报告说，后来患上阿尔茨海默氏症的研究对象的脊髓液中显示出高水平的疾病相关蛋白。 在患者被确诊患有阿尔茨海默氏症之前 18 年，该水平就出现了较高的记录。

Then every few years, the study detected another so-called biomarker of coming trouble.

然后每隔几年，这项研究就会检测到另一种所谓的即将出现麻烦的生物标志物。

Scientists still do not know exactly how Alzheimer’s forms. The disease slowly destroys the brain, interfering with the ability to think. Alzheimer’s patients develop proteins called beta-amyloid and tau, which over time build up into plaques that block brain processes.

科学家们仍然不知道阿尔茨海默氏症是如何形成的。 这种疾病会慢慢破坏大脑，干扰思考能力。 阿尔茨海默氏症患者体内会产生一种叫做 β-淀粉样蛋白和 tau 蛋白的蛋白质，随着时间的推移，这些蛋白质会形成斑块，阻碍大脑的活动。

The new research, published in the New England Journal of Medicine, offers a timeline for how these proteins develop.

这项发表在《新英格兰医学杂志》上的新研究提供了这些蛋白质如何发育的时间表。

The study’s importance “cannot be overstated,” said Dr. Richard Mayeux, an Alzheimer’s specialist at Columbia University who was not involved in the research.

没有参与这项研究的哥伦比亚大学阿尔茨海默病专家理查德·梅耶克斯博士说，这项研究的重要性“怎么强调都不为过”。

“Knowledge of the timing of these physiological events is critical” for testing new ways of treating and maybe even preventing Alzheimer’s, he wrote in a piece published alongside the study report.

他在与研究报告一起发表的一篇文章中写道，“了解这些生理事件发生的时间对于测试治疗甚至预防阿尔茨海默病的新方法至关重要”。

Scientists already knew that in rare, genetic forms of Alzheimer’s that affect young people, a poisonous form of amyloid starts developing about 20 years ahead of symptoms. At some point after that, tau develops as well.

科学家们已经知道，在影响年轻人的罕见阿尔茨海默氏症遗传形式中，有毒的淀粉样蛋白在症状出现前约 20 年就开始形成。 此后的某个时刻，tau 蛋白也会发育。

The new findings show the order of such biomarker changes common to age-related Alzheimer’s.

新发现显示了与年龄相关的阿尔茨海默病常见的生物标志物变化顺序。

Researchers with Beijing’s Innovation Center for Neurological Disorders compared 648 people who were later found with Alzheimer’s to an equal number who remained healthy. The amyloid finding in future Alzheimer’s patients was the main discovery.

北京神经疾病创新中心的研究人员将 648 名后来被发现患有阿尔茨海默病的人与同等数量的健康人进行了比较。 在未来的阿尔茨海默氏症患者中发现的淀粉样蛋白是主要发现。

Differences in tau were found next, followed by a marker of trouble in how neurons communicate. A few years after that, the study found differences in brain shrinkage and cognitive test scores between the two groups.

接下来发现了 tau 蛋白的差异，然后是神经元通讯方式出现问题的标志。 几年后，研究发现两组之间的大脑萎缩和认知测试分数存在差异。

“The more we know about viable Alzheimer’s treatment targets and when to address them, the better and faster we will be able to develop new therapies and preventions,” said Claire Sexton, director of scientific programs with the Alzheimer’s Association. She noted that blood tests are coming soon that promise to also help by making it easier to find amyloid and tau.

“我们对可行的阿尔茨海默病治疗目标以及何时解决这些目标了解得越多，我们就能更好更快地开发新的疗法和预防措施，”阿尔茨海默病协会科学项目主任克莱尔·塞克斯顿说。 她指出，血液测试即将推出，这也有望帮助更容易地找到淀粉样蛋白和 tau 蛋白。

More than 6 million Americans, and millions more worldwide, have Alzheimer’s. There is no cure.

超过 600 万美国人以及全世界数以百万计的人患有阿尔茨海默病。 没有治愈方法。

But last year, Leqembi became the first approved drug that could slow the worsening of early Alzheimer’s for a few months. The drug works by clearing away some of the amyloid protein. Other drugs are being developed to target tau.

但去年，Leqembi 成为第一个获批的药物，可以在几个月内减缓早期阿尔茨海默病的恶化。 该药物的作用是清除一些淀粉样蛋白。 其他针对 tau 蛋白的药物正在开发中。