Today we discuss how frog skin stem cells were recently used to create microscopic living machines, how scientists are trying to replicate the powerful punch of a mantis shrimp, and a new breakthrough in the creation of an oral insulin tablet.
Today we discuss how frog skin stem cells were recently used to create microscopic living machines, how scientists are trying to replicate the powerful punch of a mantis shrimp, and a new breakthrough in the creation of an oral insulin tablet.
Frog Skin Cells
Shrimp Robots
Oral Insulin Tablet
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/frog-skin-cells-shrimp-robots-oral-insulin-tablet
[SFX: INTRO MUSIC/WHOOSH]
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today you’ll learn about how frog skin stem cells were recently used to create microscopic living machines, how scientists are trying to replicate the powerful punch of a mantis shrimp, and a new breakthrough in the creation of an oral insulin tablet!
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
CALLI: Nate, do you remember that story we did a while back about the robot finger that researchers grew human-like skin over?
NATE: Oh yeah! That was so cool...and kind of creepy, but mostly cool.
CALLI: Well, there’s a new experiment that’s somewhat similar but equally fascinating. Scientists recently took skin stem cells from frog embryos, and started growing them in a lab, basically creating microscopic living machines. These cells grew into small blobs called xenobots. Even though they don’t have nerve cells or a brain, they’re capable of some pretty impressive things!
NATE: Wait, scientists started growing their own living…frogs?
CALLI: Sure did. And they have been for a while, because if you recall we also talked about scientists growing new frog legs. In this new study, Scientists took those skin stem cells from the frog embryos and put them in a lab just to see what would happen. As the researchers watched, the stem cells organized themselves into balls, and started to grow to about half a millimeter wide. After only three days…these clusters of cells started to swim.
NATE: Swim!? Did they revert back to their frog origins and grow a tadpole tail or legs to kick with?
CALLI: It's way stranger than that. The cells didn’t look or act at all like a frog. Frogs have these structures on their skin called cilia, they’re like tiny hairs covering the frog. Usually, these hairs help spread mucus and fight off pathogens. But in the xenobots, the clumps of cells used the cilia to wiggle and propel themselves through the water. They repurposed an existing structure…in just a matter of days.
NATE: That's wild! I feel like usually that kind of change happens over thousands of years through evolution, this feels like a huge deal! Some may even say unheard of!
CALLI: Scientists were thrilled, they say it marks a big step in using science not just to understand how the world exists, but to start asking what is possible.
NATE: Well when it comes to xenobots, what even is possible?
CALLI: Right, well like I said before, these clumps of cells don’t have a brain or nerve cells, but they were able to use the cilia to help them swim through thin tubes, and even navigate mazes. And maybe most impressively, if you cut the zenobots in half, they’re capable of healing themselves by kind of just….zipping that gash back up.
NATE: So can these things die? Or are they immortal?
CALLI: The scientists say that they live for about 10 days without food. But, if you feed them sugar, they can live longer, about four months, but they don’t get bigger than the initial little zenobot clump.
NATE: I wish I could live on only sugar. So what’s next for these xenobots?
CALLI: At the moment, it's pretty unclear. There are a lot of potential uses, and it seems like there’s just a question about where to start. Maybe we could use them to clean waterways, or use them in super tiny spaces like arteries. But whether we find a job for these xenobots or not, it's still really thrilling because we have opened the door to a whole new world of what is possible, scientifically speaking.
NATE: That’s very exciting, but it’s also a little scary. Have we thought about what happens if we start making living machines? Just because we can….should we?
CALLI: Such a great question, Nate, and one that is starting a whole bunch of conversations. Right now, there’s no consensus on what the ethics are around creating living machines. We haven’t even begun to consider the repercussions and unintended consequences. It's an exciting world, but one we have to be careful in.
NATE: I’ll be on the lookout for a xenobot invasion.
[SFX: WHOOSH]
NATE: Calli, when I say the words “Camel Corps,” “Iceworm,” and “Project Pigeon,” what do you think of?
CALLI: Oh man. Other than totally badass animal movies that I would absolutely watch… it sounds like codenames to me!
NATE: BINGO! All of these were experiments by the US Military. Camels were brought to the US in the 1800s in an experiment to replace horses out west, scientists thought they could train pigeons to carry and drop bombs, and Iceworm was actually just a series of bases underneath Greenland.
CALLI: Okay, first of all, I’m ready to plan a field trip for us to the Iceworm bases in Greenland and second, why are you bringing this up?
NATE: The US Military is at it again, this time developing… robot shrimp.
CALLI: SHRIMP? The delicious seafood commonly found in pasta? Color me curious. What’s the reason for the research?
NATE: Researchers at Harvard University and Duke University are interested in the biology of mantis shrimp, specifically, those who use their calcified claws to strike, punch, and pulverize anything or anyone in their way. Gaining a better understanding of the mechanisms of these creatures will help us discover more about animal biology AND help us expand our knowledge of engineering. What’s so interesting is that their claws accelerate faster than a bullet from a gun. It’s said that just one strike can knock the arm off a crab or break through the shell of a snail. Some mantis shrimp have even fought an octopus - and won.
CALLI: Wow! That’s one strong prawn!
NATE: Exactly. So the idea is to manifest that power into a robot. Biologists have been fascinated by these deadly, ultra-fast prawn punches for decades, and new advancements in high-speed imaging have made it possible to see and measure these strikes to try to replicate them, but some of the mechanics are a bit confusing.
CALLI: What do you mean?
NATE: So, a lot of small organisms like frogs or chameleons will do these ultra fast movements, like hopping and darting, by storing elastic energy before releasing it super quick through a kind of latching mechanism in their limbs. Think of a mouse trap or a bow and arrow, but a biological one. In mantis shrimp, there are these two small structures in their muscle tendons called sclerites that are like the springs in the mouse trap. When these release, something causes a delay which builds up EVEN MORE momentum and power, like a hand holding up the mousetrap before letting it go down. The mantis shrimp evolved this method for catching their prey but researchers are still trying to nail down exactly how the mechanism works.
CALLI: And how are they doing that?
NATE: They studied and observed the mantis shrimp using these behaviors and then they built a physical, robotic model. Once they had the robot, the team was able to develop a mathematical model of the movement.
CALLI: What did they find?
NATE: They mapped out four distinct phases of the mantis strike, starting with the sclerites and ending with the strike of the appendage. They found that after the sclerites unlatch, the actual shape of the limb keeps holding onto that energy, building it up and holding it in place before it reaches a certain point and then BOOM - the latch releases.
CALLI: So, they recreated a deadly shrimp hit but.. Only partially?
NATE: Exactly. To date, their super shrimp is faster than any similar devices made at the same scale. The only thing is it’s not quite as fast, or strong, as the OG mantis shrimp… yet.
CALLI: Very cool, Nate. But what’s the point? I’m trying to picture Super Shrimp Serum creating whole armies of Captain Shrimp-merica super soldiers.
NATE: Well, by combining physical and analytical models of the shrimp punch, this could help biologists better understand some of nature’s other extraordinary feats. You know, like how trap jaw ants snap their jaws so quickly or how frogs propel themselves so high.
CALLI: That’s awesome. Just let me know when the Shrimps join the MCU. I’ll definitely be tuning in.
[SFX: WHOOSH]
CALLI: Nate, there is some amazing news I want to tell you about. I recently read a study about a potential new insulin treatment for diabetics with no needles involved!
NATE: Oh my, that’s huge, Calli. How did that come about?
CALLI: A team of researchers at the University of British Columbia have developed an oral replacement for daily insulin injections. Even better - they’ve discovered that their new pills were just as efficient at delivering insulin!
NATE: That’s incredible, especially considering the amount of people are suffering from diabetes.
CALLI: Absolutely. Approximately one in ten Americans – around 37.3 million people – have diabetes in one form or another, and as many as a THIRD of them treat it with injectable insulin. That’s a minimum, a MINIMUM, of over 12 million needles, DAILY, that don’t need to be used. On top of that, the cost to even make insulin would be cheaper, and therefore it could BE cheaper.
NATE: And a huge quality of life improvement for people living with type 1 diabetes.
CALLI: It’s definitely a potential improvement for their mental health. Injected insulin can carry a bit of social stigma so privacy is definitely needed and that can be really stressful. A tablet or pill could get rid of those extra steps. And this is something that the head researcher cares deeply about as well - the inspiration for this research comes from his diabetic father who has been injecting insulin 3-4 times a day for the past 15 YEARS. So, he understands what a burden that is.
NATE: Wow, that would really motivate someone to find a better method. What are the success rates so far?
CALLI: A whopping 100 percent, Nate.
NATE: No freaking way.
CALLI: Well, they say “nearly” 100 percent. But those are incredible odds. Even if the tablet was 90% or 99.9% effective, it still would deliver an accurate dose of insulin so getting up to 100% was exactly what the researchers wanted to see.
NATE: That’s amazing but, if this is so effective, why hasn't there already been an insulin tablet?
CALLI: It’s not for lack of trying. There are several other oral insulin alternatives in various stages of testing and development right now, but none are as effective as this breakthrough. The oral tablets need a lot more units of insulin than an injection, so that makes things more difficult in advancing the treatment.
NATE: Have they started human trials yet?
CALLI: Unfortunately, no. As we’ve heard time and time again on this show, the researchers need more time, funding, and collaborators for that to happen. They don’t think it should be hard to find those though; this is almost certainly going to be more sustainable, more cost-effective, and more accessible for millions of people around the world.
NATE: Howso?
CALLI: Well, where do you think the needles for insulin go after they're done? You obviously can’t reuse most needles, so that’s a LOT of environmental waste you’d avoid with a digestible tablet.
NATE: Well, that’s very exciting. Hopefully they’re able to find funding soon! I’ll keep my fingers crossed till then!
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: Scientists have created small living machines called xenobots from skin stem cells. While these living machines are opening doors to what is possible, they’re also raising moral and ethical conundrums.
NATE: Did you know the mantis shrimp has one of the strongest punches in the world? I didn’t, but the US army did, and they’re currently developing a robot that emulates the force projected by these small crustaceans. If successful, this shrimp punch robot could help us better understand the biology of many living creatures with mysterious mechanisms!
CALLI: Over 37 million people in America have some form of diabetes, and around 12 million treat it with injected insulin, but if a recent invention goes to market, that number could one day plummet to zero. Ingestible insulin is now a reality and could potentially save anybody with diabetes money, stress, and waste - all that’s needed now is more funding for the treatment to continue research!