Hi, this is Science Friday. I'm Ira Fletto. Today on the show, eyeballs. As we age, all sorts of things can go awry in our eyes. Our vision gets blurry, cataracts may make our eyes cloudy, and we're more at risk for diseases like glaucoma. So how do we keep our eyes healthy for longer? According to new research published in Nature Communications, one clue may lie in the eyeball of, you're not going to guess this, the eyeballs of Greenland sharks. These sharks can survive for more than 400 years. And because they live for so long and their eyeballs look glazed over, scientists thought they were basically blind. That is until this new study found that the shark's eyes are healthier than we originally thought. So how can Greenland sharks maintain their healthy eyes for so long? And can it tell us anything about preserving our own eyesight? Joining me is the study author, Dr. Dorotas Kovranska-Kravchik, associate professor at the University of California, Irvine, who studies the mechanisms of aging. Welcome to Science Friday. Yeah, hello. Thank you for having me. Nice to have you. So what is it about Greenland sharks that caught your eye, so to speak? Yes. There was a study in 2016 in Science, so very good journal, talking about how long sharks can live. And they found that these sharks can live, as you said, over 400 years. But at the same time, they released a lot of movies. And the movies were really cool. I mean, you know, they were like people swimming along the shark and filming them. And what I noticed is that the sharks are observing the swimmers. So they're looking back at the swimmers or are looking at them, is what you're saying? Exactly. They were following them with their eyes. Well, that was just first observation. So I was really, I mean, for me as a eye lover, it was very interesting and so on. And then I read the paper carefully and I realized that there is a strong assumption that those animals do not see. That was weird for me because they were definitely following the light especially. And that was like a moment there. Yeah. That was surprising. And then the occasion came when we realized that we can actually contact the scientist there and ask if they still have some leftover eyeballs from their studies because they collected some eyeballs exactly for the carbon dating, which they did on lens. It's very interesting. Just to order up a box of shark eyeballs here. Something like that. Well, of course, we wrote to them a nice, nice message and asked if they are interested in this collaboration. And they said, yes, sure, we can send you some eyes we have in freezer, but we can also collect some more eyes during our next trip. Wow. That was amazing. So please describe what these eyeballs look like from me. Spare no details here. I want to know exactly. Well, they are quite slimy. They are quite slimy. So when you get them. They are frozen and usually. And first of all, they are size of the, let's say, small apple or big plum, you know, so they are pretty big. And then when we get them frozen, we don't want to lose the specimens. So what we do, we actually cut them with the little thin saw in half. I'm cringing. I'm cringing. I know it sounds like that, but you know, we don't want to spare material. Those animals are living so long and we want to be sure we study everything we can with the material we have. So what's it like once you get cut, you cut through it? What's it like to do that? Well, it's just, it's like ice, right? It's frozen. So it's like cutting through ice. But what is really amazing when you open, you just see cross section, you know, like through the eye and it's how beautiful, how big it is. And also how protected it is from the pressure. There is a very thick walls around so the eye is not collapsed when they are deep in the sea. It's just already, you know, like amazing. You just already see that there are adaptations to how they live and where they live. So it is a low light detecting. So there's no really high resolution, but they definitely see shapes passing by, a light passing by and of course, probably see if there's big, small and so on, so on. And of course, with these sharks living up to 400 years, I would expect that when you cut open the eye, you might see aged things like we have like cataracts and signs of aging. But you didn't see that, did you? So that's the surprising part. There is no signs of the deposits behind the retina. There is no signs of some degeneration of the part of it, some cells disappearing. Everything looks very organized and ready to go, ready to work. As opposed to that happening in humans. Yes, yes. As we get older. Exactly. When you start to look at the human eyeballs, which we fortunately received from donors, we can see already like around 40, 50 years old donors. We start to see some deposits, some debris, some, you know, things in the eye that we can presume they were already disturbing a little bit vision. But then with 67 years old eyeballs, now we start to see plethora of different problems. So what is it about aging that our eyes fall apart as we get older? What's going on there? I don't want to be pessimist, but actually we all fall apart. Everything falls apart, not just your eyes. Not just our eyes. Our eyes seem to actually work pretty well for a long time and they have really a lot of mechanisms to resist the stress. But what seems to happen is that our eyes are exposed to many different small stresses, impacts and challenges through the life. And they always have to repair themselves. So there's always a little bit of damage, repair, damage, repair. But, you know, if you have it so often, sometimes the repair will not be perfect, right? Or sometimes the mechanism of repair is not efficient in given type of damage. So that's why with time, you know, the system is less and less resilient or more and more susceptible to next stress. And this is how it happens, you know, with time, the tissue goes. Mad. Tell me about it. I'm a direct witness to that. Well, what is it? I guess this is what you would like to know. What is it about the Greenland sharks that they can prevent all of this? Is there something genetic, do you think? So, yes. So there are two things that we think happen. First of all, the environment is really cold, so it slows down spandabolism. But then we looked into the more into molecular biology of these eyeballs and we realized that the molecular level, they seem to have very efficient, highly expressed or highly present DNA repair mechanism, which means there is a push to keep this vision healthy longer. Do we have the same gene mechanism that maybe is not expressed? That's actually a beautiful question. We have exact same mechanism. We have exact same genes, but maybe they are not expressed highly enough. So one of those genes that we shown, we have studied a little bit before. So we know already that this mechanism is crucial. But now we have a proof that if you actually turn it up, it may be protective. So what we need to do is figure out how to hack the Greenland sharks, ice saving method and this genetics and possibly use it for a treatment for us. That would be the simplest translation of the findings. And obviously it sounds like that. We have to test it very much. But I do think that if we can increase the efficiency of the DNA repair mechanism, we actually may be able to protect vision longer. So now we started many different experiments to think about it creatively, how we could really bring it to human. Where do you go from here? Yeah. Thank you for that question. So what our laboratory is interested in is to really use the knowledge about the DNA damage repair mechanism and how it's boosted in the shark eye to try to understand whether we can do the same first in mammals. So I can mouse and then hopefully we can translate it nicely to the human eye. We just need to think about the ways either through small molecules or maybe even gene therapy to bring this to human. And that's where you come full circle because you're a molecular biologist. Yes. This is how we work. Well, I'm glad you've shared that with us. Thank you for taking time to be with us today. Thank you. Thank you for asking those great questions and having me share my love. Dr. Dorotas Kovranska Kravchik, associate professor at the University of California, Irvine, who studies the mechanisms of aging. Coming up after the break, a different kind of eye. This one is the eye in the sky that's changing our understanding of the universe. Of course, I'm talking about the James Webb Space Telescope. Stick around. How does AI even work? Where does creativity come from? What's the secret to living longer? Ted Radio Hour explores the biggest questions with some of the world's greatest thinkers. They will surprise, challenge and even change you. Listen to NPR's Ted Radio Hour, wherever you get your podcasts. Hey, it's Flora. Speaking of remarkable eyes, one of you dear listeners called us with questions about the biggest eye in the sky, the James Webb Space Telescope and what kind of technology had to be invented to see farther back in time than ever before. And we live to serve. So here to see that we get some answers is the James Webb Space Telescope Project Scientist, Dr. Michael M. Welcome back, Makarena. And thanks for doing this. Thank you so much for having me, Flora. Slowly to be back. Let me start by introducing you to our listener who called with this question. Hi, my name is Leon and I'm from Kennewick, Washington. Leon's 18 years old. So I'm just finishing up high school, but I'm taking classes at the local community college and then I'll be going to university. I'm going to the university. I'm going to the university. I'm going to the university. I'm going to the university. I'm going to the university. I'm going to the university. I'll be going to university after I serve a mission for two years for my church. And Leon's into space and he's into James Webb. And he heard this thing about the James Webb Space Telescope that caught his ear. I heard once that the gold-plated mirrors on the James Webb Space Telescope have remarkably small imperfections. The analogy I heard was that if it were the size of the United States, the highest bump would be the size of a baseball. Makarena, that seems wild to me. Is that true? It's actually not quite true because it is better than a baseball. Really? Yeah, really. And I think Liam is referring to those tiny bumps and imperfections that, you know, they are there and you cannot do anything about them. And those would be give or take a 30 percent smaller than a baseball if a mirror would be the size of the United States. We're in golf ball territory. Oh, yeah. That's amazing. I mean, why do you need such a perfectly flat mirror? Well, because when you want to observe the very first galaxies that were created in the universe or when you want to observe nearby objects, but with a really exquisite detail, you do need that size and you do need that perfection. Otherwise, things will be blurry. For sharpness. Very cute. It is sharpness and acuity. OK, let's get to Leon's other question. Here's what he wants to know. My question is what the biggest hurdles were in terms of what technology they needed to develop and how they got past those and how they figured out solutions to their most complex problems. What were the biggest challenges? Are there things that still haunt you? No, because it's going so well. Well, because because he's interested in the mirrors, there were many technologies developed. The manufacturing of the mirrors was fresh and new, but specifically the polishing of the mirrors required new technologies and the measurement of those imperfections required development of new techniques. And this is because when you build one of these telescopes, they are a one of. So you really have to do new things to make it as perfect as possible. So what did you have to develop to make sure it was as flat as it was? There is a lot when it comes to building this telescope of processes and engineering. So in this case, would be, first of all, select the right material, make sure the material is going to behave well when it gets really, really cold because it's in a space and it would be very cold, but also make sure that the polishing they are made out of beryllium and metal and that they have to be polished to perfection. So, for instance, there was a development of a technique to measure those tiny bumps, to measure them very precisely to make sure that it was as flat as possible. And today that technique of part of that technique, it's used to diagnose and to really measure surfaces of eyes to make sure that they can be perhaps be used by optometrists or by doctors to the surgeries. Oh, to see if your if your eye has any imperfections on it. Right. Just to measure the surface of the eye. So it is actually used in medicine, which is one of those, you know, spin-offs, as NASA calls them, technology you develop for a purpose and then it trickles down into society. Wow. That's really cool. That's exactly what Leon was asking about. Yeah, he has really good questions. You know, before I hung up, I asked Leon why he was interested in space. And and his answer caught me off guard. This might be an unusual answer, but I'm a deeply religious person and science is kind of for me has strengthened my relationship with God. And I feel like helps me to understand the creator a little bit better. And so it just makes me feel, I guess, hope and and joy for something greater out there than than us. Macarena, I loved this sentiment and I wondered how it would hit you. That's a lovely answer. I think when it comes to the universe and we look at any of, you know, even the night sky or any of the telescopes results, you always wonder about the big questions, asking where do we come from? Where are we going? What is the origin of everything in this case? What is the origin of the universe in the big band? So I think there is an interplay that is very clear there. Yeah, and there's awesomeness in both fields, right? And I mean that in the, you know, the true sense of the word that there's awe. Yeah, there is absolute awe. And think of the big one, right? That particular moment, which is the creation of our universe. Or the so we can study the universe afterwards, but it can also be. Addressed from a religious perspective as the moment of creation. So I think there's a lot to think about that. Leon had one more thing to tell you, Makarena. What you've done is super awesome. And thank you for what you've done for science and exploring space. That's fantastic. And thank you to Leon, but this is of course the effort of thousands and thousands of people. It takes a village. And none of this, none of this happened by chance. These were very well planned and thought of engineering the science and science objectives and really teamwork that made it happen. But thank you. And it really works my day to hear that. Thank you, Makarena. Thank you for joining us today. Thank you. Dr. Makarena Garcia-Marine is a project scientist for JWST. And Leon, thank you for the wonderful question. This show is produced by Russia Aready. And if you have a question that you need an answer to, give us a ring, 877-4-Sci Fry. Catch you tomorrow. I'm Flora Lichtman.
