Could your brain repair itself? - Ralitsa Petrova

你的大脑能够自我修复吗？-瑞丽沙 • 佩拓娃（Ralitsa Petrova)

翻译人员: Qing Chen 校对人员: Yuanqing Edberg

Imagine the brain could reboot,

想象一下大脑能够自我重启，

updating its withered and damaged cells with new, improved units.

升级自己那些发育不良或者受损的细胞 为新的，改良的单元。

That may sound like science fiction,

这也许听起来跟科幻小说似的，

but it's a potential reality scientists are investigating right now.

但有朝一日这可能成为现实， 科学家们也正在研究。

Will our brains one day be able to self-repair?

我们的大脑能够有朝一日 进行自我修复吗？

It's well known that embryonic cells in our young developing brains

众所周知，初期正在发育的大脑里 的胚胎细胞

produce new neurons,

能够产生新的神经元，

the microscopic units that make up the brain's tissue.

即构成脑组织的微单元。

Those newly generated neurons migrate to various parts of the developing brain,

这些新生成的神经元 游走到发育中大脑的不同部分，

making it self-organize into different structures.

并自我组织成为不同的结构。

But until recently,

但直到最近，

scientists thought cell production came to an abrupt halt soon after this initial growth,

科学家们都一直认为，细胞增殖在初始发育过后 不久就突然中止了，

leading them to conclude that neurological diseases,

这一想法导致他们认为， 神经性疾病

like Alzheimer's and Parkinson's,

比如阿兹海默症， 或者帕金森症

and damaging events, like strokes, are irreversible.

跟中风一样，是无法逆转 的毁灭性损害。

But a series of recent discoveries

但一系列的最新发现

has revealed that adult brains actually do continue to produce new cells

显示，成人大脑竟然 至少在三个特殊的位置

in at least three specialized locations.

继续生成新的细胞。

This process, known as neurogenesis,

这一过程叫做神经发生，

involves dedicated brain cells, called neural stem cells

也就是说专门的大脑细胞， 叫做神经元细胞

and progenitor cells,

以及祖细胞,

which manufacture new neurons or replace the old ones.

它们能够生成新的神经元 或代替老的神经元。

The three regions where neurogenesis has been discovered

科学家发现，神经发生这一过程 存在于三个脑部区域：

are the dentate gyrus, associated with learning and memory,

一个是与学习及记忆相关的海马齿状回，

the subventricular zone, which may supply neurons to the olfactory bulb

一个是供给嗅球神经元的脑室下区，

for communication between the nose and brain,

负责鼻子和脑部的交流，

and the striatum, which helps manage movement.

还有帮助管理运动的纹状体。

Scientists don't yet have a good grasp on exactly what role

科学家目前还未掌握

neurogenesis plays in any of these regions,

在这些脑部区域的神经发生 具体扮演什么角色，

or why they have this ability that's absent from the rest of the brain,

或者说为什么它们仅存于这三区， 而非整个大脑。

but the mere presence of a mechanism to grown new neurons in the adult brain

但是在成人大脑中新神经元生成的 这一机制本身的存在

opens up an amazing possibility.

开放了一种惊人的可能性。

Could we harness that mechanism to get the brain to heal its scars

我们是不是能利用这一机制 让大脑来修复自身的创伤，

similar to how new skin grows to patch up a wound,

就像新皮长出来修复伤口，

or a broken bone stitches itself back together?

或者像断骨自我接合那样？

So here's where we stand.

那么我们现在的情况是这样：

Certain proteins and other small molecules that mimick those proteins

一部分蛋白质和其它模拟 这些蛋白质的小分子

can be administered to the brain

能被供给到大脑，

to make neural stem cells and progenitor cells

使得神经干细胞及祖细胞

produce more neurons in those three locations.

在上述的三个区域 生成更多的神经元。

This technique still needs improvement

这项技术仍需改善，

so that the cells reproduce more efficiently

让细胞更有效地增殖，

and more cells survive.

让更多的细胞活下来。

But research shows that progenitor cells from these areas

然而，研究表明来自这些区域的祖细胞

can actually migrate to places where injury has occurred

竟然还能游离到 损伤发生的部位，

and give rise to new neurons there.

并在那儿生成新的神经元。

And another promising possible approach

另一项有希望成功的做法

is to transplant healthy human neural stem cells,

就是移植健康的 在实验室里培育的

which are cultured in a laboratory, to injured tissue,

人类神经元细胞到损伤组织中，

like we can do with skin.

就跟植皮一样。

Scientists are currently experimenting

科学家们正在试验中，

to determine whether transplanted donor cells can divide, differentiate

以测定这些移植的供体细胞 是否能够分裂，分化

and successfully give rise to new neurons in a damaged brain.

并成功地在受损大脑中 生成新的神经元。

They've also discovered

科学家们还发现

that we might be able to teach other kinds of brain cells,

我们也许能够教其它种类的脑细胞

such as astrocytes or oligodendrocytes

如星细胞或者单树突胶质细胞

to behave like neural stem cells and start generating neurons, too.

模仿神经元细胞的行为， 也来开始生成新的神经元。

So, a couple of decades from now will our brains be able to self-repair?

那么几十年以后， 我们的大脑就能自我修复了？

We can't say for sure,

我们没有十足的把握，

but that has become one of the major goals of regenerative medicine.

但是这已然成为了 再生医学的主要目标。

The human brain has 100 billion neurons

人类大脑有一千亿的神经元，

and we're still figuring out the wiring behind this huge biological motherboard.

现阶段我们仍在研究这一硕大的 生物主板是如何布线的。

But everyday, research on neurogenesis brings us closer to that reboot switch.

但每天，关于神经发生的研究都让我们 离那个所谓的重启开关又更近了一步。