Alzheimer's Disease. Around the world, tens of millions of people have Alzheimer's disease, a debilitating brain disorder that gradually destroys a person's memory and other cognitive abilities.

阿爾茨海默病。 阿爾茨海默病是一種使人衰弱的腦部疾病，會逐漸破壞人的記憶力和其他認知能力。

It takes a heavy toll on both patients and families, as caring for a loved one with Alzheimer's can be emotionally overwhelming and financially difficult. While doctors have studied Alzheimer's for decades, conducting hundreds of clinical trials, there is still no effective preventive treatment or cure.

阿爾茨海默氏症給患者和家庭都帶來了沉重的負擔，因為照顧患有阿爾茨海默氏症的親人在情感上可能會不堪重負，在經濟上也會十分困難。 儘管醫生對阿爾茨海默氏症進行了數十年的研究，並進行了數百次臨床試驗，但仍然沒有有效的預防性治療或治癒方法。

So why is Alzheimer's disease so difficult to treat?

那麼，為什麼阿爾茨海默病如此難以治療呢？

Alzheimer's accounts for 60-80% of all dementia patients worldwide. Dementia is a broader term used to describe a variety of conditions that affect a patient's memory, thinking skills, and everyday functions.

阿爾茨海默氏症患者佔全球痴呆症患者總數的 60-80%。 痴呆症是一個更廣泛的術語，用於描述影響患者記憶力、思維能力和日常功能的各種疾病。

Most Alzheimer's patients first notice symptoms in their 60s, experiencing mild memory problems, like losing track of dates or forgetting what they just learned.

大多數阿爾茨海默氏症患者在 60 多歲時首次發現症狀，出現輕微的記憶問題，如記不住日期或忘記剛學過的內容。

Some experience other changes, like frequent shifts in mood, increased anxiety and agitation, and problems with coping in new situations. Symptoms typically progress gradually over years, and eventually, a person with Alzheimer's may require constant care.

有些人會出現其他變化，如情緒經常變化、焦慮和煩躁增加，以及在應對新情況時出現問題。 阿爾茨海默氏症的症狀通常會在數年內逐漸加重，最終，阿爾茨海默氏症患者可能需要持續的護理。

Some rare forms of Alzheimer's are caused by a single inherited gene variant.

有些罕見的阿爾茨海默氏症是由單一遺傳基因變異引起的。

But most of the time, Alzheimer's is due to the complex interaction of multiple genes, in combination with lifestyle and environmental factors.

但大多數情況下，阿爾茨海默氏症是由多種基因與生活方式和環境因素的複雜相互作用造成的。

So it's impossible to predict who will develop the disease. Alzheimer's involves a long chronic process, resulting in many changes to the brain that likely starts to unfold at least one to two decades before symptoms first appear.

是以，我們無法預測誰會患上這種疾病。 阿爾茨海默氏症是一個漫長的慢性過程，會導致大腦發生許多變化，而這些變化很可能在症狀首次出現前至少一二十年就已經開始了。

So it's been difficult for scientists to pinpoint exactly what triggers this process, and what causes the many symptoms of Alzheimer's.

是以，科學家們一直難以確定究竟是什麼觸發了這一過程，又是什麼導致了阿爾茨海默氏症的多種症狀。

But thanks to continued research, they're beginning to put this puzzle together. Initially, scientists noticed that the brains of Alzheimer's patients display an abnormal buildup of a compound called beta-amyloid.

不過，由於研究的不斷深入，他們開始將這一難題拼湊起來。 最初，科學家們注意到，阿爾茨海默氏症患者的大腦中會異常堆積一種叫做β-澱粉樣蛋白的化合物。

Beta-amyloid is created when a large protein, amyloid beta-precursor protein, or APP, is broken down.

β-澱粉樣蛋白是一種大型蛋白質，即澱粉樣蛋白β-前體蛋白（APP）被分解後產生的。

APP plays an essential role in the brain, aiding in neural growth and repair.

APP 在大腦中發揮著重要作用，有助於神經生長和修復。

However, in Alzheimer's patients, it's thought that APP is improperly cleaved, creating sticky beta-amyloid byproducts, which easily clump together.

然而，在阿爾茨海默氏症患者中，人們認為 APP 被不適當地裂解，產生了粘性的 beta 澱粉樣蛋白副產品，這些副產品很容易凝結在一起。

These plaques can build up in the spaces between neurons, and interfere with normal brain signaling. But this likely isn't the full story.

這些斑塊會堆積在神經元之間的空隙中，干擾大腦的正常信號傳遞。 但這可能並不是故事的全部。

While all patients with Alzheimer's have plaques, not all people with plaques have or will develop dementia.

雖然所有阿爾茨海默氏症患者都有斑塊，但並不是所有有斑塊的人都已經或將要患上痴呆症。

And Alzheimer's symptoms don't always become more severe as plaques accumulate in the brain.

阿爾茨海默氏症的症狀並不總是隨著斑塊在大腦中的累積而變得更加嚴重。

In the 1980s, another protein, tau, emerged as a possible contributor.

20 世紀 80 年代，另一種蛋白質 tau 成為可能的致病因素。

Tau's normal role is as a scaffolding protein to help reinforce the internal structure of neurons and give them their shape.

Tau 的正常作用是作為一種支架蛋白，幫助加固神經元的內部結構，並賦予其形狀。

But in Alzheimer's patients, tau is modified and misfolded, causing it, like beta-amyloid, to become sticky and to clump.

但在阿爾茨海默氏症患者體內，tau 會發生改變和錯誤摺疊，導致它和β-澱粉樣蛋白一樣變得粘稠並凝結成塊。

These tau tangles accumulate within neurons and are toxic, causing the cells to eventually die. In patients, plaques normally appear before tangles.

這些 tau 結在神經元內積聚，具有毒性，最終導致細胞死亡。 在患者中，斑塊通常出現在糾結之前。

Yet questions still remain.

然而，問題依然存在。

Do amyloid plaques trigger tau dysfunction?

澱粉樣蛋白斑塊會引發 tau 功能障礙嗎？

And why exactly do these abnormal proteins lead to such specific disease symptoms? To make matters more complex, recent studies have found that Alzheimer's is closely linked to changes in the way immune cells, called microglia, function in the brain.

這些異常蛋白質究竟為什麼會導致如此特殊的疾病症狀呢？ 更復雜的是，最近的研究發現，阿爾茨海默氏症與被稱為小膠質細胞的免疫細胞在大腦中的功能變化密切相關。

Others have found that Alzheimer's may also be caused by problems in the junctions between neurons, called synapses.

還有人發現，阿爾茨海默氏症也可能是由神經元之間的連接（稱為突觸）出現問題引起的。

And alterations in the way the brain produces and burns energy may also be an underlying factor.

大腦產生和燃燒能量的方式發生改變也可能是一個潛在因素。

Together, all this suggests that Alzheimer's is likely caused by a complex cascade of events. And teasing out the order of events, and how to stop it once it starts, will take more research.

所有這些都表明，阿爾茨海默氏症很可能是由一系列複雜的事件引起的。 要弄清事件發生的順序，以及如何在事件發生後加以阻止，還需要更多的研究。

But there are things patients can do to better manage symptoms.

不過，患者也可以做些事情來更好地控制症狀。

Staying active, learning new skills, and even participating in daily activities like household chores seems to slow disease progression.

保持活躍、學習新技能，甚至參與家務等日常活動，似乎都能延緩疾病的發展。

Medications that target neurotransmitters, the brain's signaling molecules, can slow memory loss and help with learning and reasoning.

針對神經遞質（大腦的信號分子）的藥物可以減緩記憶力衰退，並有助於學習和推理。

And scientists continue to develop new therapies.

科學家們還在繼續開發新的療法。

For example, drugs that target beta-amyloid have shown promise in slowing the disease and reducing plaque accumulation in the brain. Alzheimer's disease won't go away anytime soon.

例如，針對β-澱粉樣蛋白的藥物已顯示出減緩疾病和減少大腦中斑塊堆積的前景。 阿爾茨海默病不會很快消失。

Dementia cases are expected to double in the next 20 years.

在未來 20 年內，痴呆症病例預計將翻一番。

But continued research holds the promise of better treatment, and perhaps one day, prevention, as scientists piece the Alzheimer's puzzle together. What do you think will happen to Alzheimer's disease?

但是，隨著科學家們對阿爾茨海默氏症拼圖的不斷拼湊，持續的研究有望帶來更好的治療，也許有一天還能起到預防作用。 您認為阿爾茨海默病會怎樣？

Will it regenerate itself, updating its own damaged cells?

它會自我再生，更新自己受損的細胞嗎？

This might sound like science fiction, but it's actually something scientists are seriously looking into.

這聽起來像是科幻小說，但實際上科學家們正在認真研究。

Learn about neurogenesis with this video.

通過這段視頻瞭解神經發生。