Cells Use ‘Bioelectricity’ To Coordinate and Make Group Decisions

A cell shrinks, due to a change in its bioelectrical properties, before it is extruded from tissue.

细胞在从组织中挤出之前，由于其生物电特性的变化而收缩。

The “lightning” flash represents a change in light refraction as the membrane is depolarized and water exits the cell.

当膜去极化并且水离开细胞时，“闪电”闪光代表光折射的变化。

Original video quality enhanced using AI with creator’s approval.

经创作者批准，使用 AI 增强原始视频质量。

(Images taken every two minutes.)

（每两分钟拍摄一次图像。）

We’re used to thinking of the brain as an electric organ.

我们习惯于将大脑视为一个电子器官。

The rest of the body?

身体的其余部分？

Not so much.

没那么多。

But it would be a mistake to dismiss your other tissues as dumb hunks of electrically inert flesh.

但如果你把你的其他组织视为无电的肌肉块，那就大错特错了。

Even the protective layers of cells that compose your skin and line your organs use electrical signals to make decisions, according to recent research.

根据最近的研究，即使是构成皮肤和器官的细胞保护层也使用电信号来做出决定。

Results published in Nature show that cells use bioelectricity to coordinate a complex collective behavior called extrusion, a vital process that ejects sick or struggling individual cells from tissue to maintain health and keep growth in check.

《自然》杂志发表的结果表明，细胞利用生物电来协调一种称为“挤出”的复杂集体行为，这是一种将患病或挣扎的单个细胞从组织中排出以维持健康并控制生长的重要过程。

Merciless as it might seem, extrusion helps keep you alive.

尽管挤压看似无情，但它却能帮助你活下去。

It’s vital for the health of protective epithelial tissues, and when it goes wrong, it can contribute to disease, including cancer and asthma.

它对于保护性上皮组织的健康至关重要，如果出现问题，就会导致疾病，包括癌症和哮喘。

Until now, it’s been unclear how cells were singled out for this process.

到目前为止，尚不清楚如何为这个过程挑选出细胞。

According to the new results, as epithelial tissue grows, cells are packed more tightly together, which increases the electrical current flowing through each cell’s membrane.

根据新的结果，随着上皮组织的生长，细胞更加紧密地堆积在一起，从而增加了流过每个细胞膜的电流。

A weak, old, or energy-starved cell will struggle to compensate, triggering a response that sends water rushing out of the cell, shriveling it up and marking it for death.

虚弱、衰老或缺乏能量的细胞将难以补偿，从而引发一种反应，使水冲出细胞，使细胞枯萎并标记其死亡。

In this way, electricity acts like a health checkup for the tissue and guides the pruning process.

通过这种方式，电力就像对组织进行健康检查并指导修剪过程。

“This is a very interesting discovery — finding that bioelectricity is the earliest event during this cell-extrusion process,” said the geneticist GuangJun Zhang of Purdue University, who studies bioelectrical signals in zebra fish development and wasn’t involved in the study.

“这是一个非常有趣的发现——发现生物电是细胞挤出过程中最早的事件，”普渡大学遗传学家张广军说，他研究斑马鱼发育中的生物电信号，但没有参与这项研究。

“It’s a good example of how a widening electronic-signaling perspective can be used in fundamental biology.”

“这是一个很好的例子，展示了如何在基础生物学中使用更广泛的电子信号视角。”

The new discovery adds to the growing assortment of bioelectrical phenomena that scientists have discovered playing out beyond the nervous system, from bacteria swapping signals within a biofilm to cells following electric fields during embryonic development.

这项新发现进一步丰富了科学家们发现的神经系统之外的生物电现象，从细菌在生物膜内交换信号到细胞在胚胎发育过程中遵循电场。

Electricity increasingly appears to be one of biology’s go-to tools for coordinating and exchanging information between all kinds of cells.

电似乎越来越成为生物学上在各种细胞之间协调和交换信息的首选工具之一。

“People just kind of relegated [bioelectricity] to ‘This is just neurons.’ No — it’s all of our bodies,” said study author Jody Rosenblatt , an epithelial cell biologist at King’s College London and the Francis Crick Institute.

“人们只是将[生物电]归结为‘这只是神经元’。不，它是我们的整个身体，”研究作者乔迪·罗森布拉特 (Jody Rosenblatt) 说，他是伦敦国王学院和弗朗西斯·克里克研究所的上皮细胞生物学家。

“There are electrical currents going through your body all the time, and they’re doing things.”

“电流一直流过你的身体，它们在做事。”

It’s no coincidence that Frankenstein’s monster sprang to life with a spark.

弗兰肯斯坦的怪物凭着火花复活并非巧合。

In the late 18th century, just a few decades before Mary Shelley wrote her science fiction masterpiece, the Italian surgeon Luigi Galvani jolted the scientific community with experiments that used metal and electricity to compel disembodied frog legs to kick.

18 世纪末，就在玛丽·雪莱 (Mary Shelley) 写出她的科幻杰作的几十年前，意大利外科医生路易吉·加尔瓦尼 (Luigi Galvani) 进行了利用金属和电力迫使无实体青蛙腿踢腿的实验，震惊了科学界。

He became convinced that there was an “animal electricity” running through life.

他开始相信生命中存在着一种“动物电”。

In the late 1700s, the anatomist Luigi Galvani (left) discovered that dissected frog legs twitched when touched with an electrical spark, setting off the study of what he called “animal electricity.”

1700 年代末，解剖学家路易吉·加尔瓦尼（左）发现，解剖后的青蛙腿在接触电火花时会抽搐，从而引发了他所谓的“动物电”的研究。

Public Domain; ETH-Bibliothek Zurich / Science Source

公共领域；苏黎世联邦理工学院图书馆 / Science Source

While Galvani was later proven wrong in the details, he wasn’t totally off.

虽然伽伐尼后来被证明在细节上是错误的，但他并没有完全错了。

Virtually every cell on every branch of the tree of life expends a hefty chunk of its energy budget — in some cells, more than half — on maintaining a voltage across its membrane.

事实上，生命之树每个分支上的每个细胞都将其能量预算的很大一部分（在某些细胞中，超过一半）用于维持其膜上的电压。

The voltage difference that results, called the membrane potential, stores potential energy that can be released later.

产生的电压差称为膜电位，储存可以稍后释放的势能。

It’s like the pressure behind a dam: Gravity tugs water downhill, and dams store energy by holding water at the top of a hill.

这就像水坝后面的压力：重力将水拖向山下，水坝通过将水保持在山顶来储存能量。

Like gravity, the electrochemical force tugs charges “downhill” — positive charges stream toward negative charges and vice versa in electrical currents.

与重力一样，电化学力牵引电荷“下坡”——正电荷流向负电荷，反之亦然。

Blocking that flow, for example with a cell membrane, stores up electrical potential energy.

例如用细胞膜阻止该流动，从而储存电势能。

The electric currents that pour from our wall sockets are streams of electrons.

从墙上插座流出的电流是电子流。

In cells, “it’s quite similar, but not exactly the same,” said Elias Barriga , who studies tissue biophysics at the Dresden University of Technology.

在细胞中，“它非常相似，但不完全相同，”德累斯顿工业大学研究组织生物物理学的埃利亚斯·巴里加（Elias Barriga）说。

“We are fueled by ions.”

“我们以离子为燃料。”

Ions are atoms or molecules that carry charge because of extra or missing electrons, which give them negative or positive charges, respectively.

离子是由于额外或缺少电子而携带电荷的原子或分子，这分别赋予它们负电荷或正电荷。

They can enter and exit cells only through specialized protein channels and pumps.

它们只能通过专门的蛋白质通道和泵进入和离开细胞。

Just as hydroelectric plants can use surplus energy to pump water back up into the reservoir for later use, cells use their chemical energy to pump ions “uphill” against the electric flow.

正如水力发电厂可以利用剩余能量将水泵回水库以供以后使用一样，电池利用化学能将离子逆着电流“上坡”泵送。

By controlling the natural current and letting positive or negative charge build up on either side of their membranes, cells maintain their membrane potential.

通过控制自然电流并让正电荷或负电荷在细胞膜两侧积聚，细胞可以维持其膜电位。

And if this energy is used or leaks away, cells can replenish it by expending more of their chemical energy.

如果这种能量被使用或泄漏，细胞可以通过消耗更多的化学能来补充它。

Elias Barriga has shown that frog embryos generate electrical fields to guide cell migration.

埃利亚斯·巴里加（Elias Barriga）证明，青蛙胚胎会产生电场来引导细胞迁移。

The study of bioelectricity, formerly stranded in biology’s backwaters, is “coming back like crazy,” he said.

他说，以前陷入生物学停滞状态的生物电研究正在“疯狂地卷土重来”。

“You generate a potential: what’s inside versus what’s outside, a different concentration of ions,” Barriga said.

巴里加说：“你会产生一种势能：内部与外部、不同浓度的离子。”

“That is the source of bioelectricity.”

“这就是生物电的来源。”

Neurons make use of this biological electricity to share information.

神经元利用这种生物电来共享信息。

By releasing messenger molecules called neurotransmitters that open and close ion channels, neurons can nudge their neighbors’ membrane potentials up or down.

通过释放打开和关闭离子通道的称为神经递质的信使分子，神经元可以向上或向下推动邻近的膜电位。

If these chemical nudges push a neuron’s membrane potential beyond a threshold, the cell “spikes” — voltage-sensitive ion channels throw open the floodgates for positive sodium ions, which rush into the cell and cause a rapid voltage swing that ripples along the neuron’s length.

如果这些化学推动使神经元的膜电位超过阈值，细胞就会“尖峰”——电压敏感的离子通道打开正钠离子的闸门，钠离子冲入细胞，引起快速的电压波动，沿着神经元的长度产生波纹。

When that signal reaches the interface between neurons, voltage-sensitive channels open wide, triggering the release of neurotransmitters to more neurons downstream.

当该信号到达神经元之间的界面时，电压敏感通道会打开，触发神经递质释放到下游更多的神经元。

Muscle contraction also kicks off with a voltage spike ; neurons send electrical signals streaming into muscle fibers, triggering contractions.

肌肉收缩也会随着电压尖峰开始；神经元发送电信号流入肌肉纤维，引发收缩。

This is why Galvani’s electrified frog legs twitched, and why a jolt of electricity can jump-start a stopped heart.

这就是伽伐尼带电的青蛙腿抽搐的原因，也是电的震动可以使停止的心脏跳动的原因。

(Specialized cells in the heart use electricity to set the pace of its regular contractions.) While all tissues maintain membrane potentials, researchers don’t really know what they do.

（心脏中的特殊细胞利用电力来设定其定期收缩的速度。）虽然所有组织都保持膜电位，但研究人员并不真正知道它们的作用。

Compared to electrophysiology, which often focuses on electricity in the brain and heart, the field of bioelectricity — a grab-bag term for electrical activity everywhere else in organisms — has lagged behind, Barriga said.

巴里加说，与通常关注大脑和心脏电的电生理学相比，生物电领域（生物体中其他地方的电活动的一个笼统术语）已经落后了。

“I think that at some point it got stuck,” he said.

“我认为在某个时候它陷入了困境，”他说。

“But now I can tell you that that is coming back like crazy.”

“但现在我可以告诉你，这种情况正在疯狂地回归。”

The epithelial tissues that make up skin and line organs, blood vessels, and body cavities quietly burn about 25% of their available energy to maintain membrane voltages between minus 30 and minus 50 millivolts.

构成皮肤和线路器官、血管和体腔的上皮组织悄悄地燃烧大约 25% 的可用能量，以将膜电压维持在负 30 到负 50 毫伏之间。

But researchers interested in these tissues typically study mechanical forces, chemical signaling, and gene expression — not currents and voltage, Rosenblatt said.

但罗森布拉特说，对这些组织感兴趣的研究人员通常研究机械力、化学信号和基因表达，而不是电流和电压。

Until recently, that included her.

直到最近，这其中也包括她。

Rosenblatt has spent 25 years piecing together the details of epithelial extrusion, a process that keeps tissue growth in check.

Rosenblatt 花了 25 年时间拼凑出上皮挤出的细节，这是一个控制组织生长的过程。

Because epithelial cells grow quickly, even a slight mismatch between the rates of cell division and cell death can quickly add up to a tumor or injury.

由于上皮细胞生长迅速，即使细胞分裂速度和细胞死亡速度之间存在轻微的不匹配，也可能很快导致肿瘤或损伤。

Runaway replication can grow into cancer, while overzealous culling — as can happen in asthma — compromises the integrity of tissues.

失控的复制可能会发展成癌症，而过度的剔除——就像哮喘中可能发生的那样——会损害组织的完整性。

It’s important to get the balance right.

保持正确的平衡很重要。

Around 14 years ago, Rosenblatt and colleagues discovered that overcrowded epithelial cells are popped up and out of the tissue alive — extruded — to maintain that tissue balance as new cells grow.

大约 14 年前，Rosenblatt 及其同事发现，过度拥挤的上皮细胞会从组织中活生生地弹出（挤出），以在新细胞生长时维持组织平衡。

That raised a question: How does tissue “choose” which living cells to expel?

这就提出了一个问题：组织如何“选择”排出哪些活细胞？

In earlier work, Rosenblatt’s team watched as some cells dumped their water and shriveled up like raisins before being extruded; indeed, this shrinkage seemed to kick off the process.

在早期的工作中，罗森布拉特的团队观察到一些细胞在被挤出之前会倒掉水分并像葡萄干一样枯萎。事实上，这种收缩似乎拉开了这一进程的序幕。

But the researchers didn’t know what caused the cells to shrink in the first place.

但研究人员并不知道是什么导致细胞缩小。

They didn’t work on bioelectricity and were unaware of any effect it might have.

他们没有研究生物电，也不知道它可能产生的任何影响。

The cell biologist Jody Rosenblatt studies extrusion, the process by which a tissue expels cells to prevent overcrowding.

细胞生物学家乔迪·罗森布拉特（Jody Rosenblatt）研究挤压，即组织排出细胞以防止过度拥挤的过程。

Her lab recently described bioelectricity as helping the tissue “choose” which cells to extrude.

她的实验室最近将生物电描述为帮助组织“选择”要挤出的细胞。

In further experiments, they were able to prevent the cells from shrinking by blocking a pressure-sensitive ion channel in the cell membrane that opens when squeezed.

在进一步的实验中，他们能够通过阻断细胞膜中受挤压时打开的压力敏感离子通道来防止细胞收缩。

They decided to see if blocking other ion channels might interfere with extrusion too.

他们决定看看阻断其他离子通道是否也会干扰挤出。

“We got so many hits, we were just like: Jesus, this is crazy,” Rosenblatt recalled.

“我们获得了如此多的点击率，我们就像是：天哪，这太疯狂了，”罗森布拉特回忆道。

One of those hits was a voltage-gated potassium channel, like those that open up during a neuron’s voltage spike.

其中之一是电压门控钾通道，就像神经元电压尖峰期间打开的通道一样。

It struck Rosenblatt as “weird” enough to follow up on.

罗森布拉特觉得这“很奇怪”，足以跟进。

Using special dyes that reveal the voltage across cell membranes, the scientists found that epithelial cells destined for extrusion — and only those cells — lose their membrane potential about five minutes before shrinking and being extruded.

使用显示细胞膜电压的特殊染料，科学家们发现，注定要被挤压的上皮细胞（而且只有这些细胞）会在收缩和被挤压前大约五分钟失去膜电位。

The result was clear: Extrusion kicks off with an electrical signal.

结果很明显：挤压随着电信号开始。

Instead of sending neurotransmitters back and forth like neurons, densely packed epithelial cells squeeze each other.

密集的上皮细胞并不像神经元那样来回发送神经递质，而是相互挤压。

As the tissue gets more crowded, the squeezing intensifies.

随着组织变得更加拥挤，挤压也会加剧。

This opens pressure-sensitive ion channels, which allow positive sodium ions to leak across the squashed cells’ membranes and into the cell.

这会打开压力敏感的离子通道，使正钠离子穿过被压扁的细胞膜渗入细胞内。

Faced with this challenge, a healthy cell will use its chemical energy to activate pumps to push sodium back out and restore its normal voltage.

面对这一挑战，健康的细胞将利用其化学能来激活泵，将钠推出并恢复其正常电压。

But stressed or unhealthy cells without energy to spare can’t keep up.

但是，如果细胞受到压力或不健康，没有多余的能量，就无法跟上。

Their membrane voltage falters, throwing open those “weird” voltage-sensitive channels.

它们的膜电压不稳定，打开那些“奇怪的”电压敏感通道。

When that happens, water pours out of the cell in a “lightning” flash clearly visible in microscope images, Rosenblatt said.

罗森布拉特说，当这种情况发生时，水会以“闪电”的方式从细胞中涌出，在显微镜图像中清晰可见。

Once a cell loses 17% or more of its volume, it is extruded.

一旦细胞体积减少 17% 或更多，它就会被挤压。

Her working hypothesis is that a biochemical cascade set off by the shrinkage contracts motor proteins, which mechanically extrude the cell.

她的工作假设是，收缩引发的生化级联会收缩运动蛋白，从而机械地挤出细胞。

In this way, bioelectrical flow across cell membranes lets tissues test which cells are the least healthy and mark them for extrusion.

通过这种方式，穿过细胞膜的生物电流可以让组织测试哪些细胞最不健康，并标记它们以进行挤压。

“They’re always pushing against each other and bullying each other.

“他们总是互相推挤、互相欺凌。

And what they’re doing is probing each other for which one’s the weakest link,” Rosenblatt said.

他们所做的就是互相探测对方最薄弱的环节，”罗森布拉特说。

“It’s a community effect.”

“这是一种社区效应。”

At the University of California, San Diego, the biophysicist Gürol Süel studies electricity in bacterial biofilms , which are collectives composed of single-celled bacteria that can also survive independently.

在圣地亚哥加利福尼亚大学，生物物理学家 Gürol Süel 研究细菌生物膜中的电，生物膜是由单细胞细菌组成的集合体，也可以独立生存。

The signaling that Rosenblatt and her team described in human tissues has several things in common with electrical mechanisms Süel has described in microbes — and which appear again and again across the tree of life.

罗森布拉特和她的团队在人体组织中描述的信号传导与苏埃尔在微生物中描述的电机制有几个共同点，并且这些信号在生命之树中一次又一次地出现。

“It’s a very elegant study, very nice results,” he said of the new research.

“这是一项非常优雅的研究，取得了非常好的结果，”他谈到这项新研究时说道。

“And conceptually, it makes sense.”

“从概念上讲，这是有道理的。”

Gürol Süel studies how bacteria in biofilms use bioelectricity to communicate and coordinate.

Gürol Süel 研究生物膜中的细菌如何利用生物电进行交流和协调。

A membrane potential “tells you, in one glance almost, about the state of the cell,” he said.

他说，膜电位“几乎一眼就能告诉你细胞的状态”。

Electricity increasingly appears to be one of evolution’s go-to solutions for integrating multiple streams of information.

电力似乎越来越成为集成多种信息流的进化首选解决方案之一。

Epithelial tissues use it to keep tabs on crowding.

上皮组织用它来监视拥挤情况。

Neurons compile input signals from multiple sources into a spiking output.

神经元将来自多个源的输入信号编译成尖峰输出。

A Venus flytrap snaps shut when sensory hairs with touch-sensitive ion channels react to prey.

当带有触敏离子通道的感觉毛发对猎物做出反应时，捕蝇草就会突然关闭。

These channels are tuned to trigger a voltage spike and tell the trap to close only if stimulated multiple times in rapid succession.

这些通道经过调整，可触发电压尖峰，并指示陷阱仅在快速连续多次刺激时关闭。

“The membrane potential is so fundamental, and it is very fast,” Süel said.

“膜电位非常重要，而且速度非常快，”Süel 说。

While switching genes on and off or upping protein production could take minutes or hours, a membrane potential can flip in fractions of a second.

虽然打开和关闭基因或增加蛋白质产量可能需要几分钟或几小时，但膜电位可以在几分之一秒内翻转。

“It tells you, in one glance almost, about the state of the cell,” he added.

“它几乎一眼就能告诉你细胞的状态，”他补充道。

Ten years ago, Süel and his team showed that microbes in biofilms can spike their membrane potentials to communicate , just as neurons do.

十年前，苏埃尔和他的团队证明，生物膜中的微生物可以提高膜电位来进行交流，就像神经元一样。

Since then, they’ve shown that biofilms use electricity to coordinate tasks , prevent runaway growth , and invite free-swimming bacteria to join the collective .

从那时起，他们证明生物膜利用电力来协调任务，防止失控生长，并邀请自由游动的细菌加入集体。

Bioelectricity can even help them avoid falling victim to the tragedy of the commons: Two biofilms sharing scarce food can send electrical signals to each other to take turns eating.

生物电甚至可以帮助它们避免成为公地悲剧的受害者：共享稀缺食物的两个生物膜可以互相发送电信号，轮流进食。

Multicellular animals, too, use electrical signaling to organize themselves.

多细胞动物也使用电信号来组织自身。

Zhang, of Purdue, studies bioelectrical signaling in zebra fish, which develop striking extra-long tails when a certain ion channel is mutated.

普渡大学的张研究斑马鱼的生物电信号，当某个离子通道发生突变时，斑马鱼会长出引人注目的超长尾巴。

This suggests that electrical signaling somehow tells tissues in a developing embryo how long to grow.

这表明电信号以某种方式告诉发育中的胚胎中的组织需要生长多长时间。

Michael Levin , a researcher at Tufts University, has blocked cell channels to manipulate the membrane potentials of developing worm embryos, causing genetically identical worms to develop different body plans.

塔夫茨大学的研究人员迈克尔·莱文（Michael Levin）通过阻断细胞通道来操纵发育中的蠕虫胚胎的膜电位，从而导致基因相同的蠕虫发育出不同的身体计划。

And last year, Barriga and his colleagues showed that frog embryos generate natural electric fields that guide the migration of specific stem cells to their proper locations in the developing embryo.

去年，巴里加和他的同事表明，青蛙胚胎会产生自然电场，引导特定干细胞迁移到发育胚胎中的适当位置。

The failure of bioelectric processes might be an overlooked cause of disease.

生物电过程的失败可能是一个被忽视的疾病原因。

Cancerous cells tend to have different membrane potentials than healthy ones, and Levin has argued that some cancers might result from a breakdown in multicellularity that happens when cells can no longer use electricity to coordinate.

癌细胞往往具有与健康细胞不同的膜电位，莱文认为，某些癌症可能是由于细胞无法再利用电力进行协调时多细胞性的崩溃引起的。

For example, maybe they can no longer communicate the message “I’m struggling and should be extruded,” and the result is the uncontrolled growth and, ultimately, a tumor.

例如，也许他们无法再传达“我正在挣扎，应该被挤出”的信息，结果就是不受控制的生长，最终形成肿瘤。

Süel is convinced that bioelectricity is as old as life itself.

苏埃尔坚信生物电与生命本身一样古老。

Indeed, an electric current drives the molecular turbines that synthesize life’s universal energy currency, ATP, in every cell alive today.

事实上，电流驱动分子涡轮，在当今每个活着的细胞中合成生命的通用能量货币 ATP。

One leading origin-of-life scenario places the beginning at deep-sea hydrothermal vents.

一个主要的生命起源场景是从深海热液喷口开始的。

There, natural currents of positively charged protons could have served as a kind of primordial membrane potential and powered prebiotic chemical reactions.

在那里，带正电的质子的自然电流可以充当一种原始膜电位并为生命起源前的化学反应提供动力。

But whether life started with such a spark or not, bioelectricity’s ubiquity suggests it has deep evolutionary roots that we’re just beginning to unearth.

但无论生命是否始于这样的火花，生物电的普遍存在表明它具有我们刚刚开始挖掘的深层进化根源。

“There are a lot of interesting things that cells are probably doing, just like this paper showed, that we just don’t know yet,” Süel said.

“就像这篇论文所展示的那样，细胞可能正在做很多有趣的事情，但我们还不知道，”苏埃尔说。

“We have not uncovered even half of this.

“我们连一半都没有发现。

…

……

There’s a lot of opportunity for discovery.”

有很多发现的机会。”

Get highlights of the most important news delivered to your email inbox

获取发送到您的电子邮件收件箱的最重要新闻的摘要

Quanta Magazine moderates comments to facilitate an informed, substantive, civil conversation.

《Quanta》杂志对评论进行审核，以促进知情、实质性、文明的对话。

Abusive, profane, self-promotional, misleading, incoherent or off-topic comments will be rejected.

辱骂、亵渎、自我推销、误导、语无伦次或偏离主题的评论将被拒绝。

Moderators are staffed during regular business hours (New York time) and can only accept comments written in English.

版主在正常工作时间（纽约时间）有工作人员，并且只能接受英文评论。