Well, for me, it all began with this little fellow.

結束是從何開始的？

This adorable organism --

對我來說，它開始於這個小傢伙。

well, I think it's adorable --

這可愛的有機體，

is called Tetrahymena and it's a single-celled creature.

我認為它很可愛，

It's also been known as pond scum.

它叫做四膜蟲，是種單細胞生物。

So that's right, my career started with pond scum.

它也就是池塘浮渣。

Now, it was no surprise I became a scientist.

是的，我的職涯始於池塘浮渣。

Growing up far away from here,

我變成科學家並不讓人意外。

as a little girl I was deadly curious

我在離這裡很遠的地方長大，

about everything alive.

我小時候非常有好奇心，

I used to pick up lethally poisonous stinging jellyfish and sing to them.

對所有的生物都好奇。

And so starting my career,

我以前會撿起有致命劇毒 會螫人的水母，然後對牠們唱歌。

I was deadly curious about fundamental mysteries

所以，開始我的職涯時，

of the most basic building blocks of life,

我非常好奇，想解開最根本的謎題，

and I was fortunate to live in a society where that curiosity was valued.

想知道構成生命的基礎積木是什麼，

Now, for me, this little pond scum critter Tetrahymena

很幸運，我所在的社會 很重視好奇心。

was a great way to study the fundamental mystery

對我而言，四膜蟲 這池塘浮渣小生物

I was most curious about:

是研究我最好奇的 根本謎題的好方式：

those bundles of DNA in our cells called chromosomes.

我們的細胞內大量的 DNA，

And it was because I was curious about the very ends of chromosomes,

也就是所謂的染色體。

known as telomeres.

因為我對染色體的末端很好奇，

Now, when I started my quest,

也就是所謂的端粒。

all we knew was that they helped protect the ends of chromosomes.

當我開始探索，

It was important when cells divide.

我們只知道：它們 協助保護染色體的末端。

It was really important,

細胞分裂時，這點很重要。

but I wanted to find out what telomeres consisted of,

它相當重要，

and for that, I needed a lot of them.

但我想要了解端粒是什麼組成的，

And it so happens that cute little Tetrahymena

為這個目的，我需要很多端粒。

has a lot of short linear chromosomes,

剛好這個可愛的小四膜蟲

around 20,000,

有很多短短線性的染色體。

so lots of telomeres.

大約兩萬個，

And I discovered that telomeres consisted of special segments

所以會有很多端粒。

of noncoding DNA right at the very ends of chromosomes.

我發現端粒包括

But here's a problem.

位在染色體最末端 未編碼的特殊 DNA 區段。

Now, we all start life as a single cell.

但，有一個問題。

It multiples to two. Two becomes four. Four becomes eight,

生命是從單細胞開始的。

and on and on to form the 200 million billion cells

一個會變成兩個， 兩個變成四個，四個變成八個，

that make up our adult body.

一路這樣下去， 形成了二十萬兆個細胞，

And some of those cells have to divide thousands of times.

組成了成人的身體。

In fact, even as I stand here before you,

有些細胞需要分裂數千次。

all throughout my body, cells are furiously replenishing

事實上，即使我站在各位面前，

to, well, keep me standing here before you.

我整個身體的細胞正瘋狂地補充，

So every time a cell divides, all of its DNA has to be copied,

讓我能夠持續站在你們面前。

all of the coding DNA inside of those chromosomes,

每當一個細胞分裂， 它所有的 DNA 都會被複製，

because that carries the vital operating instructions

那些染色體中所有編碼的 DNA，

that keep our cells in good working order,

因為那帶有極重要的運作指示，

so my heart cells can keep a steady beat,

讓我們的細胞 能處於良好的工作狀態，

which I assure you they're not doing right now,

這麼一來我的心臟細胞 才能保持穩定的心跳，

and my immune cells

我向各位保證，它們現在並沒做到，

can fight off bacteria and viruses,

而我的免疫細胞，

and our brain cells can save the memory of our first kiss

能擊退細菌和病毒，

and keep on learning throughout life.

我們的頭腦細胞 能儲存我們初吻的記憶，

But there is a glitch in the way DNA is copied.

並在整個人生中持續學習。

It is just one of those facts of life.

但複製 DNA 的方式有個小毛病，

Every time the cell divides and the DNA is copied,

僅是生命的事實之一。

some of that DNA from the ends gets worn down and shortened,

每當細胞分裂、DNA 被複製，

some of that telomere DNA.

某些末端 DNA 會磨損縮短，

And think about it

一些端粒的 DNA。

like the protective caps at the ends of your shoelace.

可以用這方式來想：

And those keep the shoelace, or the chromosome, from fraying,

就像你的鞋帶末端的保護套。

and when that tip gets too short, it falls off,

它們能讓鞋帶或染色體不會被磨損，

and that worn down telomere sends a signal to the cells.

當尖端變得太短時，它就會脫落，

"The DNA is no longer being protected."

而那被磨損掉的端粒 就會發送一個訊號給細胞。

It sends a signal. Time to die.

「這 DNA 不再受到保護。」

So, end of story.

它發出訊號。是死亡的時候了。

Well, sorry, not so fast.

所以，故事結束。

It can't be the end of the story,

抱歉，沒那麼快。

because life hasn't died off the face of the earth.

故事不可能這樣結束，

So I was curious:

因為生命還沒從地球表面上消逝。

if such wear and tear is inevitable,

所以我很好奇：

how on earth does Mother Nature make sure

如果這種損耗是無可避免的，

we can keep our chromosomes intact?

大自然到底要如何確保

Now, remember that little pond scum critter Tetrahymena?

我們能保持不讓染色體受損？

The craziest thing was, Tetrahymena cells never got old and died.

還記得那池塘浮渣小生物四膜蟲嗎？

Their telomeres weren't shortening as time marched on.

最瘋狂的是，四膜蟲細胞 從來不會變老或死亡。

Sometimes they even got longer.

牠們的端粒並不會隨時間而變短。

Something else was at work,

有時甚至還會變長。

and believe me, that something was not in any textbook.

還有某樣東西在運作，

So working in my lab with my extraordinary student Carol Greider --

相信我，那某樣東西 並不在任何教科書中。

and Carol and I shared the Nobel Prize for this work --

所以，我和傑出學生 凱洛葛萊德在實驗室中合作──

we began running experiments

凱洛和我共享 這項研究贏得的諾貝爾獎──

and we discovered cells do have something else.

我們開始進行實驗，

It was a previously undreamed-of enzyme

我們發現細胞的確有其他的東西。

that could replenish, make longer, telomeres,

是先前意想不到的酶（酵素），

and we named it telomerase.

它能補充端粒，讓端粒更長，

And when we removed our pond scum's telomerase,

我們將它命名為「端粒酶」。

their telomeres ran down and they died.

當我們移除池塘浮渣的端粒酶後，

So it was thanks to their plentiful telomerase

牠們的端粒就會耗盡而死亡。

that our pond scum critters never got old.

所以要歸功於豐富的端粒酶，

OK, now, that's an incredibly hopeful message

我們的池塘浮渣才能永生不老。

for us humans to be receiving from pond scum,

那是我們人類能從池塘浮渣身上

because it turns out

得到的一個非常有希望的訊息，

that as we humans age, our telomeres do shorten,

因為結果發現，

and remarkably, that shortening is aging us.

隨著我們人類年紀增長， 我們的端粒確實會變短，

Generally speaking, the longer your telomeres,

很驚人的是， 那縮短現象讓我們變老。

the better off you are.

一般來說，你的端粒越長，

It's the overshortening of telomeres

你的狀況就會越好。

that leads us to feel and see signs of aging.

是端粒過度減短的現象

My skin cells start to die

導致我們會感到及看到老化的徵象。

and I start to see fine lines, wrinkles.

我的皮膚細胞開始死亡，

Hair pigment cells die.

我就會開始看到線條、皺紋。

You start to see gray.

頭髮色素細胞死亡，

Immune system cells die.

你就會開始看到白髮。

You increase your risks of getting sick.

免疫細胞死亡，

In fact, the cumulative research from the last 20 years

你被攻擊的風險就會提升。

has made clear that telomere attrition

事實上，過去二十年所累積的研究

is contributing to our risks of getting cardiovascular diseases,

清楚地指出，

Alzheimer's, some cancers and diabetes,

端粒損耗可能造成罹患

the very conditions many of us die of.

像是：心血管疾病、阿滋海默症、

And so we have to think about this.

某些癌症，以及糖尿病等 許多致死疾病的風險。

What is going on?

所以我們得要想想這一點。

This attrition,

發生了什麼事？

we look and we feel older, yeah.

這種損耗，

Our telomeres are losing the war of attrition faster.

我們看起來且感覺起來變老了。

And those of us who feel youthful longer,

我們的端粒在 損耗之戰中敗退得很快。

it turns out our telomeres are staying longer

至於覺得年輕時間比較長的人，

for longer periods of time,

結果發現是端粒能留比較久，

extending our feelings of youthfulness

比較長的時間，

and reducing the risks of all we most dread

延長我們對於年輕的感覺，

as the birthdays go by.

並減少我們隨著每個生日過去

OK,

而最害怕的那些風險。

seems like a no-brainer.

好。

Now, if my telomeres are connected

似乎很簡單。

to how quickly I'm going to feel and get old,

如果我的端粒和我多快感到變老

if my telomeres can be renewed by my telomerase,

及實際變老是有關聯的，

then all I have to do to reverse the signs and symptoms of aging

如果我能用端粒酶來復原端粒，

is figure out where to buy that Costco-sized bottle

那麼若我想要反轉 老化的徵兆和症狀，

of grade A organic fair trade telomerase, right?

就是要找個地方 買像好市多那樣超大罐、

Great! Problem solved.

A 級、有機、公平貿易的 端粒酶，對吧？

(Applause)

好極了！問題解決。

Not so fast, I'm sorry.

（掌聲）

Alas, that's not the case.

很抱歉，沒那麼快。

OK. And why?

唉，並不是那樣的。

It's because human genetics has taught us

那為什麼呢？

that when it comes to our telomerase,

因為人類遺傳學教導我們，

we humans live on a knife edge.

談到我們的端粒酶時，

OK, simply put,

我們人類是住在刀緣上的。

yes, nudging up telomerase does decrease the risks of some diseases,

簡單來說，

but it also increases the risks of certain and rather nasty cancers.

是的，增加端粒酶的確 可以減少一些疾病的風險，

So even if you could buy that Costco-sized bottle of telomerase,

但同時也會增加某些 很糟糕的癌症的風險。

and there are many websites marketing such dubious products,

所以，就算你能買到 像好市多那樣超大罐的端粒酶，

the problem is you could nudge up your risks of cancers.

有許多網站在行銷這類可疑的產品，

And we don't want that.

問題是你有可能增加罹癌的風險。

Now, don't worry,

我們不想要那樣。

and because, while I think it's kind of funny that right now,

別擔心，

you know, many of us may be thinking, well, I'd rather be like pond scum.

因為，雖然我覺得有點好笑，

(Laughter)

也許此刻很多人正想著， 我寧可像池塘浮渣一樣。

There is something for us humans

（笑聲）

in the story of telomeres and their maintenance.

在這關於端粒以及維護端粒的真相中

But I want to get one thing clear.

還是有我們人類可以學習之處。

It isn't about enormously extending human lifespan

但我想先澄清一件事。

or immortality.

重點並不是將人類壽命期間延長很多

It's about health span.

或是永生不死。

Now, health span is the number of years of your life

重點是「健康期間」。

when you're free of disease, you're healthy, you're productive,

健康期間，就是你人生中有多少年

you're zestfully enjoying life.

是沒有疾病、很健康、有生產力、

Disease span, the opposite of health span,

能夠熱情享受人生的。

is the time of your life spent feeling old and sick and dying.

相對於健康期間的「疾病期間」，

So the real question becomes,

指的就是你人生中有多長時間 覺得自己老、病、和垂死。

OK, if I can't guzzle telomerase,

所以，真正的問題變成是，

do I have control over my telomeres' length

如果我無法狂飲端粒酶，

and hence my well-being, my health,

我是否能控制端粒酶的長度，

without those downsides of cancer risks?

進而控制我的福祉、我的健康，

OK?

而沒有癌症風險的壞處？

So, it's the year 2000.

好嗎？

Now, I've been minutely scrutinizing little teeny tiny telomeres

所以，那是 2000 年。

very happily for many years,

多年來，我很快樂地、分分鐘鐘地

when into my lab walks a psychologist named Elissa Epel.

持續仔細觀察著那些極微小的端粒，

Now, Elissa's expertise is in the effects of severe, chronic psychological stress

直到有一天，名叫伊莉莎埃佩爾的 心理學家走入了我的實驗室。

on our mind's and our body's health.

伊莉莎的專長在於嚴重慢性心理壓力

And there she was standing in my lab,

對於我們身、心健康的影響。

which ironically overlooked the entrance to a mortuary, and --

她出現在我的實驗室，

(Laughter)

很諷刺的是從實驗室 可以眺望停屍間的入口，而且──

And she had a life-and-death question for me.

（笑聲）

"What happens to telomeres in people who are chronically stressed?"

她有個生死問題要問我。

she asked me.

「有慢性壓力的人， 他們的端粒會發生什麼事？」

You see, she'd been studying caregivers,

她這樣問我。

and specifically mothers of children with a chronic condition,

她一直在研究照護者，

be it gut disorder, be it autism, you name it --

特別慢性病孩童的母親，

a group obviously under enormous and prolonged psychological stress.

可能是腸病，可能是自閉症， 任何你想得到的──

I have to say, her question

這個族群很顯然處在 巨大且長期的心理壓力之下。

changed me profoundly.

我不得不說，

See, all this time I had been thinking of telomeres

她的問題深深改變了我。

as those miniscule molecular structures that they are,

一直以來，

and the genes that control telomeres.

我從小分子結構的角度來思考端粒

And when Elissa asked me about studying caregivers,

和控制端粒的基因。

I suddenly saw telomeres in a whole new light.

當伊莉莎問我 關於照護者的問題時，

I saw beyond the genes and the chromosomes

我突然從全新的角度去看端粒。

into the lives of the real people we were studying.

我超越了基因和染色體，

And I'm a mom myself,

看到我們所研究的真實人類的生活。

and at that moment,

我自己也是個母親，

I was struck by the image of these women

在那一刻，

dealing with a child with a condition

我被這個影像震撼了：

very difficult to deal with, often without help.

這些女子通常靠一己之力照顧孩子，

And such women, simply,

有非常難處理的疾病的孩子， 往往沒有幫手。

often look worn down.

這類女子，很顯而易見，

So was it possible their telomeres were worn down as well?

經常看起來是耗盡了精力的模樣。

So our collective curiosity went into overdrive.

有沒有可能她們的端粒 也被損耗掉了呢？

Elissa selected for our first study a group of such caregiving mothers,

我們共同的好奇心 促使我們加倍努力。

and we wanted to ask: What's the length of their telomeres

伊莉莎為我們的第一項研究 選了一群照護母親，

compared with the number of years that they have been caregiving

我們想要問：她們的端粒長度

for their child with a chronic condition?

和她們照顧有慢性疾病孩童多少年

So four years go by

有什麼關聯？

and the day comes when all the results are in,

所以，經過了四年，

and Elissa looked down at our first scatterplot

所有結果都進來的那一天，

and literally gasped,

伊莉莎看著我們的 第一張資料散佈圖，

because there was a pattern to the data,

真的是倒抽了一口氣，

and it was the exact gradient that we most feared might exist.

因為資料的確呈現出了模式，

It was right there on the page.

且正是我們最怕存在的斜線。

The longer, the more years that is,

就在那裡，呈現在那一頁上。

the mother had been in this caregiving situation,

母親在照護情境中的時間

no matter her age,

越久、越多年，

the shorter were her telomeres.

不論她幾歲，

And the more she perceived

她的端粒都會比較短。

her situation as being more stressful,

而且，她若越是感受到

the lower was her telomerase and the shorter were her telomeres.

她所處的情境有很大的壓力，

So we had discovered something unheard of:

她的端粒酶就會越少， 她的端粒也就會越短。

the more chronic stress you are under, the shorter your telomeres,

所以我們發現了以前沒聽過的事：

meaning the more likely you were to fall victim to an early disease span

越是在長期壓力之下， 你的端粒就會越短，

and perhaps untimely death.

意味著，你越可能很早就罹患疾病，

Our findings meant that people's life events

也可能最終會比較早死。

and the way we respond to these events

我們的發現意味著， 人一生經歷的事件、

can change how you maintain your telomeres.

以及我們對這些事件的因應方式，

So telomere length wasn't just a matter of age counted in years.

能夠改變你的端粒的維護狀況。

Elissa's question to me,

所以端粒長度並不只是 把年齡換算成年數。

back when she first came to my lab, indeed had been a life-and-death question.

伊莉莎一開始到我實驗室問的問題，

Now, luckily, hidden in that data there was hope.

的確是個生死的問題。

We noticed that some mothers,

幸運的是，在那些 資料中也藏有希望。

despite having been carefully caring for their children for many years,

我們注意到，有些母親

had been able to maintain their telomeres.

雖然多年來都一直 很細心照顧她們的孩子，

So studying these women closely revealed that they were resilient to stress.

卻仍然能維持著她們的端粒。

Somehow they were able to experience their circumstances

仔細研究這些女性， 發現她們對壓力的恢復力很強。

not as a threat day in and day out

她們能夠以某種方式，

but as a challenge,

不一天到晚視她們 所經歷的情況為威脅，

and this has led to a very important insight for all of us:

而視為是挑戰，

we have control over the way we age

這就導出了對於我們所有人 都非常重要的洞見：

all the way down into our cells.

我們能夠控制我們老化的方式

OK, now our initial curiosity became infectious.