TEDxGalway | September 2017
Michel Dugon: The secrets of spider venom
Spider venom can stop your heart within minutes, cause unimaginable pain -- and potentially save your life, says zoologist Michel Dugon. As a tarantula crawls up and down his arm, Dugon explains the medical properties of this potent toxin and how it might be used to produce the next generation of antibiotics.
ABOUT THE SPEAKER
Michel Dugon · Zoologist, venom researcher
Michel Dugon researches the potential of spider venom as a source
of novel therapeutic agents.
Transcript:
Well, hello. This is Sophie. It's all right, don't worry, everything's going to be fine.
There are some people on the balcony that are very happy to be up there now.
So this is Sophie -- not Sophia -- no, Sophie. She has a French name. And you wonder why?
So Sophie, for most people, is the incarnation of terror, really. She's far too leggy, she's far too hairy, and she's far too big to ever be trusted. But to me, Sophie is a fantastic feat of bioengineering. You see, Sophie is a testimony to all those creatures that have managed to survive since the beginning of time; all those animals that have managed to have offspring generation after generation, until this day.
You see, over one billion years ago, the first primitive cells started to evolve on this planet. It took spiders 430 million years to become what they are now: one of the most versatile, one of the most diverse and one of the most evolved groups --of predators to ever walk this earth.
It's actually quite sporty to give a speech while wrangling a tarantula, I have to say.
So, we shouldn't forget that Sophie -- and in fact, all of us -- we all are a testimony to all those ruthless battles that actually were won consistently by all our ancestors, all our predecessors. In fact, all of us, every single one of you, is in fact an uninterrupted, one-billion-years-old success story. And in the gaze of Sophie, that success is partly due to what she has in her chest, just under her eyes. In there, she has a pair of venom glands that are attached to a pair of fangs, and those fangs are folded into her mouth. So, without those fangs and without this venom, Sophie would have never managed to survive.
Now, many animals have evolved venom systems in order to survive. Nowadays, any species of venomous snakes, any species of spider, any species of scorpion, has its own venom signature, if you will, made out of dozens, if not hundreds, of chemical compounds. And all of those compounds have evolved purely for one purpose: disable and, eventually, kill.
Now, venom can actually act in many different ways. Venom, believe me, can make you feel pains that you've never felt before. Venom can also make your heart stop within minutes, or it can turn your blood into jelly. Venom can also paralyze you almost instantly, or it can just eat your flesh away, like acid. Now, all of these are pretty gruesome stories, I know, but, to me, it's kind of music to my ears. It's what I love. So why is that? Well, it's not because I'm a nutcase, no.
Just imagine what we could do if we could harvest all those super powerful compounds and use them to our benefit. That would be amazing, right? What if we could, I don't know, produce new antibiotics with those venoms? What if we could actually help people that are suffering from diabetes or hypertension? Well, in fact, all those applications are already being developed by scientists just like me everywhere around the world, as I speak. You see, hypertension is actually treated regularly with a medication that has been developed from the toxin that is produced by a South American viper. People that have type 2 diabetes can be monitored using, actually, the toxin produced by a lizard from North America. And in hospitals all around the world, a new protocol is being developed to use a toxin from a marine snail for anesthetics.
You see, venom is that kind of huge library of chemical compounds that are available to us, that are produced by hundreds of thousands of live creatures. And --
Oh, sorry, she just wants to go for a little walk.
Spiders alone are actually thought to produce over 10 million different kinds of compounds with potential therapeutic application. 10 million. And do you know how many scientists actually have managed to study so far? About 0.01 percent. So that means that there is still 99.99 percent of all those compounds that are out there, completely unknown, and are just waiting to be harvested and tested, which is fantastic. You see, so far, scientists have concentrated their efforts on very charismatic, very dangerous animals -- vipers and cobras or scorpions and black widows. But what about all those little bugs that we actually have all around us? You know, like that spider that lives behind your couch? You know, the one that decides to just shoot through the floor when you're watching TV and freaks you out? Ah, you have that one at home as well.
Well, what about those guys? Do they actually produce some kind of amazing compound in their tiny body as well? Well, an honest answer a few months ago would have been, "We have no clue." But now that my students and myself have started to look into it, I can tell you those guys actually are producing very, very interesting compounds. And I'm going to tell you more about that in a second, but first, I would like to tell you more about this "we are looking into it." How does one look into it?
Well, first of all, my students and I have to capture a lot of spiders. So how do we do that? Well, you'd be surprised. Once one starts to look, one finds a lot of spiders. They actually live everywhere around us. Within a couple of hours, we are capable of catching maybe two, three, four hundred spiders, and we bring them back to my laboratory, and we house each of them in its own individual home. And we give each of them a little meal. So now I know what you're thinking: "This guy's nuts. He has a spider B&B at work ..."
No, no it's not exactly that, and it's not the kind of venture I would advise you to start. No, once we're done with that, we wait a few days, and then, we anesthetize those spiders. Once they're asleep, we run a tiny little electric current through their body and that contracts their venom glads. Then, under a microscope, we can see a tiny little droplet of venom appearing. So we take a hair-thin glass tube, a capillary, and we collect that tiny droplet. Then, we take the spider and we put it back into its home, and we start again with another one. Because spiders are completely unharmed during the process, it means that a few days later, once they've produced a little bit of venom again and they've recovered, we can release them back into the wild.
It takes literally hundreds of spiders to just produce the equivalent of one raindrop of venom. So that drop is incredibly precious to us. And once we have it, we freeze it, and we then pass it in a machine that will separate and purify every chemical compound that is in that venom. We're speaking about tiny amounts. We're actually speaking about a tenth of a millionth of a liter of compound, but we can dilute that compound several thousand times in its own volume of water and then test it against a whole range of nasty stuff, like cancer cells or bacteria. And this is when the very exciting part of my job starts, because this is pure scientific gambling. It's kind of "Las Vegas, baby," for me.
We spend so many hours, so much resources, so much time trying to get those compounds ready, and then we test them. And most of the time, nothing happens. Nothing at all. But once in a while -- just once in a while, we get that particular compound that has absolutely amazing effects. That's the jackpot. And when I'm saying that, actually, I should take out something else from my pocket -- be afraid, be very afraid.
Now, in that little tube, I have, actually, a very common spider. The kind of spider that you could find in your shed, that you could find in your basement or that you could find in your sewer pipe, understand: in your toilet. Now, that little spider happens to produce amazingly powerful antimicrobial compounds. It is even capable of killing those drug-resistant bacteria that are giving us so much trouble, that are often making media headlines. Now, honestly, if I was living in your sewer pipe, I'd produce antibiotics, too.
But that little spider, may actually hold the answer to a very, very serious concern we have. You see, around the world, every single day, about 1,700 people die because of antimicrobial-resistant infections. Multiply that by 365, and you're reaching the staggering number of 700,000 people dead every single year because antibiotics that were efficient 30, 20 or 10 years ago are not capable of killing very common bugs. The reality is that the world is running out of antibiotics, and the pharmaceutical industry does not have any answer, actually, any weapon to address that concern. You see, 30 years ago, you could consider that 10 to 15 new kinds of antibiotics would hit the market every couple of years. Do you know how many of them hit the market in the past five years? Two. The reality is that if we continue this way, we are a few decades away from being completely helpless in front of infections, just like we were before the discovery of penicillin 90 years ago.
So you see, the reality is that we are at war against an invisible enemy that adapts and evolves a lot quicker than we do. And in that war, this little spider might be one of our greatest secret weapons. Just a half a millionth of a liter of a venom, diluted 10,000 times, is still capable of killing most bacteria that are resistant to any other kind of antibiotics. It's absolutely amazing. Every time I repeat this experiment, I just wonder: How is that possible? How many other possibilities and secrets do the siblings actually have? What kind of wonderful product can we really find, if we care to look?
So when people ask me, "Are bugs really the future of therapeutic drugs?" my answer is, "Well, I really believe that they do hold some key answers." And we need to really give ourselves the means to investigate them. So when you head back home later tonight, and you see that spider in the corner of your room ...don't squash it.
Just look at it, admire it and remember that it is an absolutely fantastic creature, a pure product of evolution, and that maybe that very spider, one day, will hold the answer, will hold the key to your very own survival. You see, she's not so insignificant anymore now, is she?Thank you.
Source:www.ted.com
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