Instant Genius - The electrome, with Sally Adee

Episode Date: January 23, 2023

Every cell in our body – bones, skin, muscle, nerves – has a tiny voltage, like a battery. This bioelectricity enables our brains to send messages, but can also help us heal from injury and develop in the womb. In her new book, We Are Electric, science journalist Sally Adee explores our body’s electrome, and reveals the ways it could help us treat cancer, regenerate cells, and even halt ageing. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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I've probably heard of the microbiome. It's quite a popular subject at the moment. It's that community of bugs and bacteria that live in your gut. But have you heard about the electron? And your electron is the bioelectricity flowing through every cell of your body, and new insights into this field

could help us obtain a deeper understanding of wound healing, cancer, regeneration, and fetal development. I'm Alice Ipscombe Southwell, the managing editor at BBC Science Focus magazine. And in this episode, I talked to Sally Aidy, who is a bit of an expert on the Electroam. She's just written a new book, We Are Electric, it explores this new field of science. So, Sally, the subject of the Electroam, I certainly hadn't heard of it before I started reading your book. So what was the spark that inspired you to start writing about it?

Well, I'm a freelance science and technology journalist. I started out being on the microchips beat at an engineering magazine called I-Tri-E-E Spectrum. And on the microchips beat, I became really obsessed with neural integration of prosthetics because DARPA, which is the U.S. Defense Advanced Research Projects Agency, Darpa was at the time doing this project called revolutionizing prosthetics, and they were working on an arm that could interface with the nervous system so that a person could drive a prosthetic arm as intuitively as though they were just thinking about it. There was no sort of thinking about it. It wasn't like a clunky appendage. It was supposed to really just interface with the nervous system so that it was just like having your own arm.

They even, I think, some of the people who were working on one version called it the Luke Arm, like Luke Skywalker. So I went to DARPA Tech, which is this huge conference that they used to throw, 5,000 people, defense contractors. And I saw this thing in action where I saw a version of it. It wasn't norally integrated, but it was still so impressive. And I started asking the people who were working on it, how would this work? And so they started talking to me about these implants called Utah arrays that are sort of little like pincushion. Sort of they look like bed of nails for a ladybird. They're very tiny.

You stick them into the cortex and they read the neural activity there. They can stimulate it. They can read it. And so I started learning about all of this neural integration and neural brain computer interface stuff. And I just want, I was like, well, so the electricity that you're pumping into the brain affects us, how? And they were like, well, the electrical signals that, you know, your brain uses to communicate. And I think that's that electricity, that bioelectricity is what most people think of when they think of like the body's electricity. Because that's well characterized.

We know that, you know, the brain talks to itself and to the limbs and to the muscles using an electrical language. It's not only electrical. We also have chemicals. We have like neurotransmitters at the synapses, but the thing that takes a message from one end of a neuron to the other to get across to either the next. neuron or to a muscle, that's an electrical signal. And that's generated by these little ion channels, these little pores in a cell that let ions flow in and out, that generates a voltage, which is an electrical phenomenon. And then the voltage goes down, it goes up. There's a spike. But like, you know, this is the action potential, and that's what kicks the neurotransmitter across the

gap to the next neuron. And that's what we know. And that's really well characterized. We've known about this. We've been studying this since the late 1700s, and we got the tools to let us verify how it works and really sort of map it out in the 1970s. And so that was all very well and good, but when I started looking more into it, the history of it, sort of the patch clamp, that tool that let you look at how precisely that electrical signal is sent, I started seeing all these papers that were like, well, ion channels are present in all cells. And that's when I was like, well, why? Why? You know, if you, you know, this electrical signal is behind everything that can let you move and feel and walk and think and see and taste and smell. That's, that's all bioelectricity.

But then there's other stuff that the body also uses it for. And then I started looking into those papers. sort of found that it just goes so far beyond the nervous system, not just in mammals, not just in like our skin and our development, but also every single other organism has them. This is like a basic thing, like fungi have ion channels and plants and bacteria, and they all, you know, use electrical signaling to communicate with themselves. I think that's what surprised me most when I was looking through this. You talk about it and you call it the body's electroph. We know about our microbiome. This is our electron.

And I certainly knew that the brain and the nervous system use these electrical signals to communicate. But when you start saying that every single cell in your body has this electricity to it, it's just absolutely mind-blowing, isn't it? Yeah, it is. I mean, I think that's why I'm still, allegedly, after a person finishes writing a book, they just won't, they can't stand the topic anymore and never want to, I mean, this is what I've heard anyway. But like, I am obsessed.

I'm like, this is just my first book, like on this. There's just, there's so much else to cover, you know, there's just, it's like one of the researchers said to me, Mike Levin, it's the oldest thing about life, basically, or basically the oldest thing about life. Like once, you know, you have the first, once you have a, just a single-celled organism in, you know, floating in the ocean, whatever, billions of years ago, and it's got a membrane. And that's your first voltage. And, you know, electricity is a fundamental. sort of physical property. So why wouldn't bodies make use of it, right, for themselves? So once you have the membrane, you have the difference between electrical charges outside and inside. And then you just have to make ion channels. I'm sorry, I'm getting really nerdy. Let me just, I'm going to go back. I'm going to talk about the electron, which I can describe very simply as all the electrical dimensions and properties of biology from sort of the cellular level to the

sort of subcellular level, like the little things that are inside the cell like mitochondria, they also have a voltage, and then the way that cells combine into societies like organs, and how they sort of use their electricity to make the organ work. And so that is something that people are trying to work out now to try to understand how electricity works at all levels of biology, not just in the nervous system. So what's actually generating? that electricity inside every single cell? And you say there's like this different potential between the inside and outside of the cell. Is it just the substances in the cells that cause that difference? Because it's not like the same electricity you get plugging in your washing machine

or your dishwasher or something. Right, exactly. So that's actually, that was, I'm glad you said that because that was the cause of one of the early, some of the early skepticism about, about the presence of electricity in any part of the body. Because telegraph, you know, like in the 1800s or whatever, you have a power station, right? And it generates, you know, electricity. It goes down a wire and powers whatever it is that you need to power it. In electric eels, they have big electrogenic organs that fire off. You know, they're basically like the little power stations in an electric eel. Humans don't have any of that, which was at the root of a lot of early skepticism about the relevance of any kind of electricity in the body. Because people were like,

we don't have little electrostatic generators in ourselves. But actually, it turns out every single cell is a battery, which is something that we did not appreciate until the 1970s when Bert Sackman, Erwin Nair and Bert Sackman invented something called a patch clamp, which could look really closely at cell membranes. So permit me a really oversimplified metaphor, you've got a cell. It's just a membrane. And the, you know, the membrane is studied with all. of these little pores, and these are called ion channels. And they let in preferentially sodium and potassium ions. And because of the way, like, these little pores are kind of like, they're kind of like bouncers slash, you know, VIP entrances. So they're very preferential. They're like,

oh, I like sodium, but, no, they're like, I like potassium, but sodium, you need to stay out. And so because of these preferences, the inside of the cell is always kept at a more, slightly more negative value than the ions that sort of swim around in the soup outside of the cell. And so the inside is minus 70 millivolts, which is a very tiny amount, but it is enough to, when the balance outside shifts, a bunch of these little pores, bouncers freak out. and open the emergency exits, and then all of a sudden that minus 70 becomes zero, and then sometimes shoots up a little bit even into the positive. And this is so shocking. This is like a really shocking feeling for the cell. And it's like, you know, it throws open all of the emergency exits.

And then it goes back to, it works really hard to basically get itself back to its happy place, which is actually called its resting potential. It's kind of like this is where the cell is happy to. be. This is where it's sort of natural sort of put your feet up. This is how I like to live place. So when the sort of big voltage disruption happens, that is then passed down the cell membrane, which is what constitutes the action potential. And it is all about the ions traveling in and out of the cell passing an electrical current, basically. And what is some of the things that the electron is doing? You touched on it very briefly. I think you said it can help us with

our healing and our sense of taste. Can you just delve a bit more into that, how exactly that's working? Like, how is electricity helping me to heal? Okay, this is, this is super cool. This is, in the 70s and 80s, there was this professor at Purdue. His name is Ken Robinson. And he used to do an experiment where he would put an ammeter, he would project its dial onto a classroom. And he would, he would have two beakers of salt solution, and he would connect that up as well. M meter still doesn't move. And then he would dip his finger into one of the saltwater beakers still doesn't move. The dial still doesn't move. Then he would take a little blade and he would nick his finger. This is not something I would recommend anyone do today. This is the 70s. Everybody was crazy. But he would

Nick his finger, stick it in, and you would see the ammeter wildly go. And apparently it got gasps every time. Because when you cut yourself, what comes out along with the blood is about one microampere of current. Because the skin, actually, all those little minus 70 millivolt skin cells that I was talking about, they gang together to form the skin, and they're all connected really tightly by special ion channels called gap junctions. And they are like, it's like they're linking arms. And that all together, that generates something called a transepithelia voltage. And it's called the skin battery. And when you cut it, that's when it short circuits and all this current flows out. It's like if you cut a wire in your wall, basically what would happen is that the current has nowhere to go.

So it just goes everywhere. And so that's what was leaking into the wall. And so that's what was leaking into the water to make the ammeter dial go up. And when the current flows out, it generates an electric field, right? And the electric field, that's something that can go between like 40 and 200 millivolds per millimeter. And what it does is it's like a beacon slash homing signal for all of these cells like keratinocytes, which are like the most common skin cell, macrophages, which are like the guys who mop up the mass after you've had a wound. And these guys come flooding in. They're attracted to the cathode of this electric field, which is at the center of your wound, and that's how they get to your wound and start patching it up and repairing it.

And so what's really interesting, though, is this guy, Rich Nuchateli, created a measuring device called the Dermacorder in 2011. So this is quite recent that we've had this capability to measure the wound current in humans, or so the electric field. And what he found is that the electric field is strongest right after you've had a cut. And as it heals, it starts to slowly diminish until once you've got your sort of scar and it's all healed up, there's no more detectable wound electric field or current. And it's stronger in people who are 25 years old than it is in people who are 65.

It's about half the strength in people who are 65. So it diminishes as we age. So people are really, you know, this is early days with all of this, but people are really trying to figure out what are the electrical properties of wound healing. And can we, you know, sort of make use of them to speed up wound healing? Because there's all kinds of drugs like ion channel blockers that like block these little pores that people have messed with that if you do mess with the ion channels, then you slow down the healing. It's harder for these, for things to heal. And if you have messed with, you help amplify the wound current, you can actually speed up healing. So this podcast is sponsored by Name, Audio and Focal. With over 100 years of combined expertise, Name and Focal have been bringing music to listeners, just as the artist intended.

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Visit focal powered by name boutique. by name.com for more information. We've talked about healing there, but maybe at the other end of the scale, what I found fascinating was that if you have a cancer, that actually sort of disrupts the electricity in the body as well. I think they put sensors on someone with tumors, and they found it affected how the electrical flow. Yes, so this is an experiment from the 1940s and 50s,

which this guy, Harold Saxton Burr, he did experiments that are pretty hard to characterize now because, like, he, you know, his papers were really good and interesting, but, you know, obviously he didn't have the tools that we have now. But basically what he did is he measured the difference between the voltage in women who had ovarian cancer and women who didn't, and he found a difference. And 80 years later, that's when the really interesting stuff starts happening because people start characterizing the cellular voltage. You know how I said the nerve cells have the little negative inside charge of minus 70. So there are really interesting differences between different

kinds of cells. Musculoskeletal tissue is a very firm minus 90. It's much more sort of, you know, robust. And then like fat cells are a bit of a flabbier minus 50. So there's like an electrical identity that goes with a cell's identity. Stem cells start at about zero. So like those are the baby cells, and as they differentiate, they take on the electrical identity of, you know, whatever it is that they're going to become. What's interesting about that is that when cancer cells decide to go from healthy to cancerous, their voltage goes right back to zero. It's almost like they are deciding, like, well, I'm done with this nonsense. Like, I'm going to just go and consume and, like, do whatever I want. Don't make me, like, be a skin cell. Screw you. Like, I'm

going to be, I'm going to just go eat and proliferate. So that is. is super interesting, but also the other finding there by a guy called Mustafa Jamgauz at Imperial. He found in the late 90s that not only do they go to zero, but then they start like really, really, when they're really aggressive, cancer cells start to exhibit kind of spiking behavior that's very much like neurons. And he found that in prostate cancer, I think breast cancer cells. So this has been a really long project of his because he had to sort of always start from sort of first principles to explain this to people because people were like, what the hell are you talking about? Electricity and cancer. Like we're going to look at the genes.

And he was like, no, but you know how like your neural firing helps you, you know, get up and move around? It does the same thing for cancer. And so he was, you know, it took him a really long time. But now this is a very accepted deal. You know, cancer neuroscience now is like a really is a burgeoning field. and people are really interested in it. So there's this idea from these scientists, Ana Soto and Carlos Sonnenstein called the Society of Cells,

which has it that cancer isn't just like its own decision. Like the cancer cells aren't just making their own decisions. Like there are factors in the microenvironment that either allow or prohibit cells from deciding to proliferate however the hell they want to and going where they want to and eating whatever they want to. and so people suspect that bioelectricity is one of the environmental factors that could keep cancer in control. So if you were going to design some sort of treatment for this, you wouldn't be curing cancer. What you would be doing is you would be keeping like a tumor, basically sheltering in place.

You would keep it from metastasizing and metastasis is what kills most cancer patients. Now on to one more general question. In the film The Matrix, there's quite an iconic. image of humans being harvested for their electricity. There's all these humans lined up in pods and these little spider-like robots are crawling all over them and harvesting their electricity. So how feasible could that be in a really dystopian future? Could humans be harvested for their electricity and how much electricity are our bodies even generating? The number that gets sort of thrown around is that the body generates 100 watts a day, which is, you know, like a light bulb.

But I think generate, like getting all of that electricity out would be quite a, quite a fath would require giant banks of batteries being crawled by electrical spiders. Anyway, but what I think is much more interesting and useful is how we could use our own internally generated electricity for our own purposes. And this actually wasn't in the book, which I regret. There's this guy, Rahul Sharpescar, who worked on a design for a, implanted battery in the brain that runs on the electrons, that it strips from glucose in the cerebrospinal fluid. I went to a talk in like 2012, and when I saw him talk about that, I was just

like, this is bananas. I have to know more. But so basically, I don't know how far it's gotten, but it's basically like you could take like a very thin electron current from the cerebrose spinal fluid and use it to power like a really ultra low power brain implant, for example, in things. I don't know how far it's come. I don't know if it's stacked up. This is one of those wish list things that I never quite got to, but I keep wanting to return to. But the weird thing is that a similar design was proposed in the 1960s because we hadn't invented the lithium ion battery yet. And so they were trying really hard to figure out how to power pacemakers. Because pacemakers at the time, you had to have like, for a while, you had to have a whole,

first of all, initially you had to plug them into like the mains, which is like as terrifying as it sounds. And then they had these big VCR-sized batteries that people would have to push around like on like a trolley to have a pacemaker. So the pacemaker didn't take off until you had like really reliable batteries that would last a long time and didn't need to be changed all the time and were very small. But before they did that, they had all kinds of crazy designs. There's one, there was a pacemaker that was powered by plutonium. I think 139 people had it. And then there was this one that wanted to run off the electrons in glucose. So they had all kinds of crazy, like really interesting designs beforehand. But there's a lot of stuff that is trying

to turn the, you know, electricity and energy of the human body into something usable. I just read something about, they want to put tiny turbines in your blood, like little blood turbines. Then there's like the stuff we sort of, I think we hear about more often in the news, which is like, piezoelectric generators that would like convert like our footfalls, the mechanical energy of the footballs into electricity. So I think there are many ways to, um, and, and, you know, extract electrical energy from the body that don't require, like, basically raising us in a simulation and draining our life force. So they might not be as, like, visually impressive, although I think blood turbines is, like, super evocative. Yeah, I've just got images of, like, a little wind

turp, I'm, like, spinning around inside your plane. I know, it's nuts. I know. I know. It's really cool. Like, there's a lot of really interesting. There's so much interesting research into that. So, but yeah, so that's basically, I think that's, that's the, that's the basic. Now, is there a way that you could hack the electrical signals in your brain using like headsets or implants to make yourself smarter or improve your memory or something like that? There are many, many studies that have looked into accelerating the rate of learning, for example, using non-invasive electrical stimulation, just surface electrical stimulation. There are some really impressive results for deep brain stimulation.

like penetrating electrodes to, obviously, the sort of the gold standard of this is Parkinson's disease because deep brain penetrating electrodes can control the motor symptoms of Parkinson's disease. And so they've also started looking at that for depression, whether it can control depression. Now the thing is, there are so many of these studies. There's like a whole section in the book where I sort of go into how to report on them responsibly because the problem is like early studies are super important for, you know, they're almost like they're the clue that tells you like where to look further. But there are a lot of issues with early stage studies that make them as likely to pan out as not when you look at them in a bigger trial,

right? So it's really, this is something I haven't always known. So I think, you know, there have been sometimes when I've reported on very early studies in ways that are not necessarily, they're interesting. at the time, but they may paint a different picture than you end up getting with the bigger study. So I think right now there are really amazing implications and there's a lot of potential. You can put electricity into the brain in specific neural areas and like activate specific circuits so that people who maybe are tetraplegic can feel as if like specific fingers are being touched or, yeah, like touched or have pressure on them so that this is step, you know, one of, you know, a thousand in creating that kind of luke arm, for example. And there are really

promising studies about like being able to deal with depression. There are really interesting studies that suggest that we could sharpen focus by applying electrical stimulation. The problem is that as with the rest of the electron, There's so much about bioelectricity that hasn't been characterized. There's, just to choose one example, so with this like focus, you know, better focus thing, it works for some people and for other people. It leaves them completely cold. A similar story is for deep brain stimulation for depression.

For the people in whom it works, it's like someone turned off a switch and they'll say things like, you know, what did you do? Like how did you turn off like the OCD or the depression in my brain? but how do you find out who it is who it is that benefits in that way? Not everybody does. But obviously there is something there. There's there there. It's just that there is so much more left to do.

And I think that's part of the reason that I'm interested in projects that really take this on, like from a multidisciplinary perspective. Because if you can, one of the problems is that I think sometimes electrical stimulation, especially surface electrical stimulation, they don't have like one single parameter. Like, this is how many millie amps you use. Like, this is for how long. This is the kind of, you know, kit that you use. You know, you have to make sure the person's skull is a certain thickness that you

account for that. I mean, there's so many, like, little parameters. And it's just like, it seems like it's very discouraging when you look at all of the parameters because, like, the skull and the skin can siphon off some of the electricity that's being put onto your skull, obviously, because, you know, how, like our whole, every single cell is electric. Of course, it's going to pass it down. So, sorry, I know this is a really long waffling answer, but the thing is, I think there is promise there.

It's just that what we need to do is we need to go beyond our sort of idea that the brain is the only thing that's electric and sort of start to characterize all the electrical tissues in the body. And then also be like, well, you know, is it just neurons that are electric or is it also like the glial cells? You know, how much, sorry, I feel like we've got this very small window of biology where we're like, we've mapped this electricity super well. But then there's this entire other, like there's this dark matter, you know, where we haven't mapped the electricity. So I feel like if we do that, if we fill in those blanks, then that will cause those really promising experiments to become much more replicable and like reliable. And then, you know, then we can really, you know, start doing some really interesting. treatments for people. So what do you think is next for the science of the electron?

Are there any particular projects you're interested in there on the horizon? Yeah, well, I mean, that glucose battery after we get off the phone, I'm going to go right back there, give him another call. But I think so, but seriously, the Defence Advanced Research Projects Agency, again, is working on this program called Better, B-E-T-R, which is trying to accelerate wound healing by correlating electrical properties and parameters of wounds as they heal with all that other stuff, you know, the biochemical elements and the molecular elements. And they're going to start looking, they're going to start finding like really interesting

hacks, I guess. And that's one of them. The Air Force in the U.S. is looking at like even sort of the more basic science. They're not looking at the stuff that you can do now to make people's lives better. They're starting, they're looking, trying to look at the base. basic science. And I think stuff like that for me is the most exciting, because if you can find some, you know, group of people who can cross disciplinary lines, then, and start looking at this big picture of bioelectricity, then all of a sudden you're going to get these, like,

big paradigm shifts and all this stuff. You're going to get these really big movements forward in science. I think a lot of the stuff I discuss in the book is fascinating, but it's been done in like tadpoles, for example, or it's exploratory, it's observational. The whole book, I think, is a hint, a big clue that we need to sort of create this discipline and start really paying attention to it. And it's got such huge implications, hasn't it? We've touched on it here in the podcast where if it could help people, their wounds heal faster, it could help them identify cancer's better. It could help us, you know, people who are struggling to walk or something, and it could just bring all that back to people if we can just get some more research done on it.

Yeah, exactly. And, you know, yeah, just, you know, for people who don't have, who have non-healing wounds, this is a lot of the people who work on this. That's their, those people are their first priority because those, you know, there's nothing else you can really do if someone has a foot ulcer that won't heal. I think that the history of it is also really interesting. Just like how, why does mention of this get a side eye, you know, like people will be like, yeah, electricity. And it's just like, well, you know, it's not just people who write about it that get that. It's the scientist themselves. So one woman said that, you know, she had submitted this really carefully researched grant proposal based on some of these things that I've said, where, you know,

you've got this like, you've got very careful sort of stacking, you know, like this finding, you know, rests on this other finding that everybody is very, you know, everybody is, everybody understands. But when she submitted it, the reviewer, one of the reviewers came back with a single line. He said, do people really believe the shit anymore? So, and it's like, and it's really interesting that, you know, William Gibson said the future is already here. It's just unevenly distributed. And with bioelectricity, it's kind of the similar thing where the, the knowledge is there. It's just unevenly distributed because you have Mike Levin, who is like the sort of the biggest sort of bioelectricity researcher, I think. Like he's plugged into so many different projects.

But basically he says that he will go to one department and give a lecture and then he'll give this identical lecture at a different department. And the thing that seemed completely like obvious in one department will cause outrage in the other and vice versa because this knowledge is still siloed, I guess, some departments, you know, just so that's one thing. But the other thing is also that there's this like absolutely remarkable history of quackery from the early 1800s that like continues to sully the whole field today. Because before people could really understand either what electricity was or how the human variant interacted with it or whether it even existed at all. There were a lot of quacks who decided to make mileage out of that. And they were

just like, you know, check out my electrical tractors. They're going to cure you of, you know, everything from incontinence to impotence to, you know, cancer. It's always cancer, usually. And the breadth of whack projects still echoes down through history. And people will just bring that up occasionally. What is different now is the tools. We've had this explosion in technology that lets us actually see what's going on at the cellular level and just look at how this stuff works. And hopefully as our characterization of the electron advances,

it will really dispense with a lot of sort of electroquackery, and instead you will just have very rigorous science. Thank you for listening to this episode of Instant Genius. That was Sally A.D. Her new book, We Are Electric. The new science of our body's electrode is out on the 2nd of February. The latest issue of BBC Science Focus magazine is out now. Pick up a copy in store or visit sciencefocus.com.

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