This is the shell of a Conus Magus sea snail I collected this shell myself from a website called eBay this snail produces a Remarkable molecule that has an effect on the human nervous system. It's been approved for use as a painkiller That's a thousand times more potent than morphine and doesn't cause addiction when I heard about this it got me thinking like why is it that so many of the drugs that we take Are derived from natural sources and more specifically? Why are we finding so many new drugs in the ocean and hyper specifically Why are we finding new cancer drugs in the ocean? Basically, I ended up down this really interesting rabbit hole and I thought I'd drag you in with me So, why does Mother Nature provide us with so many useful molecules? Well for some compounds the answer is obvious Which is that the thing that we use it for is the same thing that the organism that we found it in Uses it for, penicillin is a good example of that So we use it to kill bacteria and the mold that makes it evolved the ability to make it Because it kills bacteria and that reduces competition for nutrients. The way penicillin works is really interesting by the way. So bacteria have a cell wall and they're constantly breaking down old bits of cell wall and building in new bits. To make new bits of cell wall the bacteria takes structural molecules and binds them together with cross links and that cross-linking is Facilitated by an enzyme, but the penicillin binds to the enzyme so the cross-linking can't happen So now the bacteria is still happily tearing down old bits of cell wall, but it's not building any new ones and eventually it pops It's clever There's loads of other examples of drugs that do the same thing For us as they do for the organism that we found them in but there's another category which is less obvious Take Eptifibatide, for example, figuratively take it don't actually take it It's a good example of when scientists say, okay, look if I inject myself with this thing, then I will bleed uncontrollably until I'm dead, but Hear me out. What if I just take a little bit and amazingly that approach works sometimes Eptifibatide is derived from the venom of a snake it prevents the formation of blood clots So if you're bitten by a snake, then you will bleed without stopping. That's how the snake kills its prey But if you suffer from dangerous blood clots, then you can take a small amount Eptifibatide And it might just save your life another example of a poison that is Medicinal in small quantities is Curare It's found in certain trees and it's what you add to the tip of a poison dart The way it works is really interesting it inhibits the flow of Signals down motor neurons making it hard for you to move And if you have too much of it, you won't be able to move your diaphragm You won't be able to breathe and you'll die That's how it works as a poison, but in small quantities, it works as a muscle relaxant So we've got two categories so far drugs that do the same thing for us as they do for the organism that we found them in and Drugs that are poisonous unless you take them in very small doses in which case they're medicinal We've got two more categories The third category is drugs that are poisonous for certain animals But not for humans the Conus Magus snail is a good example of that It produces a molecule called Ziconotide and it has a similar effect to the poison arrow toxin It prevents the transmission of signals down motor neurons in fish, which immobilizes the fish So the snail can eat it, but the human nervous system is quite different to the fish nervous system so instead of inhibiting transmission down motor neurons it Inhibits transition of signals down neurons that transmit pain So if you inject Ziconotide into someone's spine then they stop feeling pain You can't take the drug orally or intravenously Because it's broken down by enzymes in the body but scientists are working on a way to protect Ziconotide from those enzymes and The idea is really clever enzymes are able to attach themselves to the ends of the Ziconotide molecule. So the idea is that you chained a whole load of these Ziconotide molecules together by the ends. And then the two exposed ends at the end of the chain are joined together to form a ring now there are no exposed ends for the enzyme to attach to and the molecules can survive the journey through the human body and still work as a painkiller How cool is that? The fourth category of drugs found in nature is the Coincidence category. These are my categories, by the way. There's nothing formal about them and morphine is a good example of the coincidence category So Morphine comes from the opium poppy and it's incredibly well studied not just the drug but the plant as well But what's interesting is that there isn't much research into what morphine does for the plant. We know a lot about what it does in the human body, but not in the plant I did manage to find one paper that suggests that it's part of a healing mechanism So if the opium poppy experiences some kind of stress like a cut then that triggers a reaction where morphine turns into Bismorphine and Bismorphine is used to create strong cross links between Structural molecules. So in the site of the cut you get this solid mass basically like a scab for the opium poppy and it's just a coincidence that it also binds to the opiate receptors in the human brain There's a quote that I quite like and it goes like this What do you call alternative medicine that has been proven to work? And the answer is medicine It's a Tim Minchin quote I probably butchered it slightly But it's the kind of thing that skeptics like me enjoy saying because it neatly Dismisses all of alternative medicine and you can argue in the comments whether that's a good approach I suspect it isn't but the other reason I like this quote is because it encapsulates The history of a lot of the medicine that we use so early medicine starts out as folk remedies that have been proven to work Through clinical trials and by now the vast majority of folk remedies have been categorized as either Medicine or not medicine which means now we're actively going out and looking for new compounds in nature instead of Relying on what our ancestors have stumbled upon over the years. A really promising frontier in this Bioprospecting is the oceans literally Scientists going down in submersibles and collecting samples with their robotic arms So what does marine biology provide us with such a rich source of novel chemicals? Well, a lot of the animals that live on the ocean floor are sessile, they don't move they're literally stuck to a rock or they're really slow like a sea snail, which means they can't run away from Predators and they can't chase prey Instead they're engaged in chemical warfare; a chemical arms race. Here's the really interesting question, though Why are we finding new cancer fighting drugs in the ocean? So Trabectedin is an example of a drug that's already approved as a chemotherapy drug. The thinking goes like this if you're a creature stuck to a rock at the bottom of the ocean like The sea squirt that makes Trabectedin, then that's prime real estate down there You don't want other creatures growing up around you and using up the nutrients So if you can produce a chemical that inhibits rapid cell division Then you're going to stop new young creatures in their tracks, but if you can take that chemical and put it in a human body Maybe it will inhibit the rapid cell division of cancer cells. These drugs tend to work on Specific types of cancer or families of cancer because cancer is such a diverse disease So it means that we probably aren't ever going to find a cure-all in the oceans sadly But it's interesting to think that the next big breakthrough in the fight against cancer might be found at the end of a robotic arm deep under the waves You might have noticed some nice animations in this video. That's thanks to Dom Burgess He's got his own science youtube channel called Every Think and it's really good Like, the production value in his videos are amazing. You'll see what I mean when you go over there He's got like two thousand subscribers And he deserves a thousand times that so I really want you to go over there and show him some love. I recommend you start with a video about the effect on the human body of going to Mars Link in the description. This video is sponsored by The Body Shop, which is unusual for a channel like mine But this is how it happened I happen to meet some people from The Body Shop when I was at an event and we started talking about the science of folk remedies Because I just can't help talking about science and in particular we started talking about tea tree oil because they put tea tree oil in a lot of their products and tea tree oil is an interesting one because it's one of those folk remedies that is actually actively currently being researched at the moment and The latest findings suggest that it really does genuinely have medicinal properties anyway I made a whole video about that over on their Channel and The link is in the description as well if you want to watch that I hope you enjoyed this video. If you did, don't forget to hit subscribe. I'll see you next time
