Articles, Blog

Pain-Killing Hunger and Superpowered Diabetic Fish

August 29, 2019

SciShow is supported by Skillshare. [INTRO ♪] Pain sucks. And if that wasn’t bad enough, the best
painkillers we have tend to be incredibly addictive and can pose
other dangers, too. So scientists are on the lookout for alternatives. And a new study in the journal Cell may have
just found an unlikely ally in the hunt: hunger. On Thursday, biologists from the University of Pennsylvania reported that mice going without food for a day felt far less inflammatory pain than their
fully-fed counterparts. The team was curious about how animal brains
prioritize competing needs. Previous research had shown that hungry mice don’t react as much to painful stimuli,
but it wasn’t clear why. So they made some mice hungry by taking away
their food for a day, while others were allowed to eat normally. Then they injected their paws with a painful
chemical, which causes both acute and inflammatory pain. Acute pain is the sharp ouch that happens
right away in response to injury, while inflammatory pain is the duller throb associated with things like swelling, and
takes a little while to kick in. It’s also one of the major causes of chronic
pain in people. Both fully-fed and starved mice noticed the
acute pain of the injection, and weren’t huge fans—they kept licking
their paws. Which suggests immediate threats to the body
take top billing in the brain. But the starved mice seemed much less bothered
over time, when they should have felt the inflammatory
pain kicking in. It was sort of like they’d been given painkillers! The next step was tracking down which neurons
in the brain were involved in the pain relief. They used a technique called optogenetics
to genetically modify cells involved in brain hunger responses so they
could be turned on with laser light. They started by activating all of these neurons, which, as expected, had the pain-killing effect. Then they went through more specific circuits
of neurons one by one, using a tiny little fiber to shine the light
on certain areas of the brain. And they found that activating just one particular
set of 300 neurons provided pain relief for the mice, without
causing the animals to eat more food. And while the results are just in mice, researchers think the same basic mechanism
probably exists in humans. And if it does, studying the neurons involved
could reveal new ways to dull long-term, chronic pain—without
forcing people to starve themselves, which is always a plus. Therapies based on this would be decades away, but given the number of people struggling
with chronic pain, this small set of neurons is an exciting find. Next, we’re continuing the theme of hunger-related
evolution, this time in little fish called Mexican tetra. Some of these tetra live in caves, and after
millions of years of living in the dark, they’ve lost their eyes. But some might argue this isn’t their most
dramatic adaptation to cave life. This week, a study in the journal Nature reveals
that these fish have all the markings of being diabetic—and
yet, they’re super healthy. It’s an evolutionary puzzle that may help
us figure out how to better treat certain metabolic diseases. Despite millions of years apart from their
river-dwelling kin, the tetra that live in caves aren’t their
own species. And each cave has separately adjusted to cavern life, which makes the species a good species to study
adaptive evolution. In this case, the researchers were looking
at how the fish survive starvation. Their caves are too dark for plants to grow
in, which makes food a rarity. So cavefish may eat only once or twice a year, when seasonal floods bring in nutrients or
when bat poop lands in the water. And to survive this starvation, previous studies
had found that compared to river fish, cavefish store more
fat when they’re fed, and lose less weight when deprived of food. To figure out how they manage to pull this
off, the team gave a jolt of sugar to three groups of independently evolved cavefish and their
river-dwelling cousins. When they checked the fishes’ blood after
8 hours, the levels of glucose in the cavefish remained
high, while the river fish’s glucose had returned
to normal. In humans, that kind of result would be a
clear indicator of insulin resistance: a reduced response to the hormone insulin, which signals cells to remove sugar from the
bloodstream. It’s one of the hallmarks of type 2 diabetes. And sure enough, when biologists injected the
animals with compounds that stimulate insulin release
or insulin itself, glucose levels only dropped in the river fish. The researchers suspect this is what allows
the cavefish to quickly put on weight and use their reserves
more slowly, which is key to surviving those long periods
between meals. But they’re not sure how the fish avoid
the downsides of being diabetic. If you’re a person, having high blood sugar and being insulin resistant is a bad thing. But the cavefish didn’t seem any worse for
wear. In fact, they seem to age more slowly than
their river counterparts. When the researchers raised the fish in tanks, they found by their middle teens, the river
fish had the telltale signs of fish aging—a hunched back, loose skin,
and raggedy fins— whereas the cavefish were still going strong. The key seems to be that the cavefish somehow
limit glycation: the binding of sugar molecules to proteins, which occurs during long periods of high blood
sugar. Glycation can change how proteins function,
damaging tissues, and it’s thought to be a major driver of
diabetes-related complications. The cavefish studied had about the same number
of glycated proteins as river fish despite their lasting elevated
sugar levels. If researchers can figure out how the fish
prevent glycation, they might be able to do the same in people
with diabetes. Like hunger-based painkillers, it would take
a while to translate the research to humans. But these little diabetic fish show that there is a way to live a long, healthy life
with high blood sugar. We just have to figure out how they do it. These amazing discoveries are also thanks
to some pretty state-of-the-art tech. And if you want to stay up to date on the
latest tech news, you’ve come to the right place. Skillshare is an online community that brings
people from all over the world together to learn
from each other. So, fittingly, they’ve asked us to help
foster community by introducing you to a new YouTube channel that you might not have checked out yet as part
of their Skillshare Spotlight program. Rene Ritchie is a long-time tech blogger and
podcaster. On his new YouTube channel, Vector, he brings
his expertise to review products and unpack current news and changes
affecting the tech world. There’s a link to his most recent video
in the description where you can learn more about Vector and
get a special offer from Skillshare. Check it out! [OUTRO ♪]

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  • Reply SciShow March 23, 2018 at 9:00 pm

    Check out Rene Ritchie on Vector and get a special offer from Skillshare at:

  • Reply Almond Trees March 24, 2018 at 2:29 am

    so some hungry homeless people have endured other physical pain because hunger numbs other pain

  • Reply Disasters Today March 24, 2018 at 2:52 am

    If I am not wrong the brain prioritized pain, and a longer lasting pain is usually at lower priority the longer it goes, while hunger become priority the longer it last.

  • Reply rbfreitas March 24, 2018 at 2:53 am

    great video!!!

  • Reply Pugnado March 24, 2018 at 2:55 am

    I have those fish

  • Reply Miehos D. Silverwall March 24, 2018 at 3:12 am

    Can someone help me understand how did the cavefish gain more weight given they have insulin resistance?
    From my understanding, insulin converts glucose in the blood into fat and since the cavefish have insulin resistance, they should not have formed fat right?
    Also, given my understanding, both the riverfish and cavefish should just have the same energy absorbed and stored in their systems. The riverfish just converted their energy(glucose) into fat while the cavefish just lets it sit in its blood, but overall they have the same amount of energy.

    Please help point out flaws on my understanding and explain as simple as possible as I have no background in Science other than the Youtube vids that I watched.
    Thank you very much for helping quench my curiosity making me just a tad bit smarter!

  • Reply Ryuki 22 March 24, 2018 at 4:00 am

    Best. Band. Name. Ever.

  • Reply Javier Powell March 24, 2018 at 4:15 am

    Been dealing with chronic pain since August, i hope they develop this well.

  • Reply Maxx Nieves March 24, 2018 at 4:22 am

    I legit do not understand how anyone can get addicted to pain killers. I have chronic pain from an injury and have had multiple surgeries and I hate pain killers. I swear they put sonething in them that make you nauseous like you're dying of stomach flu. I dunno if it's just me, I just badly sprained my foot and ended up laid out sick all day cuz I took the freakin pain medicine.

  • Reply Furbloke March 24, 2018 at 4:29 am

    Christ I wish I could survive with high bloodsugars. I'm a type 1 Diabetic, have been for 8 years. This year alone I've had 8 hospital admissions with diabetic ketoacidosis and blood sugars over 30. Last year I had 19 admissions and the near before that I had 7. Its getting worse and worse, to the point where I'm experiencing asymmetric muscular atrophy on the left side of my body.

    The worst part?

    When people say "Oh you need to look after yourself better".

    With all these admissions, I've been taking my insulin and taking corrective doses to lower my BM's. To no avail.

    Life is brilliant as a diabetic. Especially when you don't respond to your insulin and basically live in hospital.

  • Reply Andrew Wright March 24, 2018 at 4:49 am

    Any solution to chronic pain that'll only likely get worse as I get older would be very welcome.

  • Reply Ben DeNardo March 24, 2018 at 4:56 am

    As someone who has dealt with chronic inflammatory pain (UC) I know one of the ways I dealt with the pain at first was basically starving myself so though very anecdotally(and wrapped up in a bunch of other issues) I've felt the dulling power of hunger on pain.

  • Reply ElementaryWatson March 24, 2018 at 5:08 am

    Poor mice ๐Ÿ™

  • Reply Johnny J March 24, 2018 at 5:30 am

    How does someone think to check a blind fish to see if it is diabetic?

  • Reply calencor March 24, 2018 at 6:30 am

    CAVE FISH to bat : i only eat once a year and you wont even poop for me!

  • Reply Nekros March 24, 2018 at 6:31 am

    Nothing will ever replace opiates, and it better stay that way. Opiates are amazing!

  • Reply Dave Abrams March 24, 2018 at 6:48 am

    Im not a fan of mice but dam we put them through some messed up stuff with test

  • Reply lekiscool March 24, 2018 at 7:37 am

    The Diabetic fish sort of coincides with the idea that diabetes first occurred in human during the Ice Age where food was scarce. If these humans rarely got to eat perhaps the diabetic ones were processing food the same way the fish do.

  • Reply Otakun Franks March 24, 2018 at 7:43 am

    How awesome is it that we are in a time where we can see a trait in an organism, recently discovered or not, and identify, and possibly harness its power?
    The best super power is taking all the others.

  • Reply ForRedmi 4A March 24, 2018 at 8:35 am

    Hi, LOVE YOUR VIDEOS!!.. recently had a query that, what if we traped Carbon dioxide from the atmosphere, compress it to dry ice and store them in leak proof containers and bury them in the Artic. And thus reduce carbon and lower the temp. in ice poles. Please it's a humble request to react on this and prove me wrong^_^^_^^_^

  • Reply Dyslexic Artist Theory on the Physics of 'Time' March 24, 2018 at 8:35 am

    Why donโ€™t you make a video on the alternative theories about the Universe on YouTube this would be interesting and good for the YouTube community!!!

  • Reply Akanksha And Aditya Singh March 24, 2018 at 9:08 am

    Well I don't understand how they store fat . Doesn't diabetes cause weight loss?

  • Reply BoomBoomBrucey March 24, 2018 at 9:45 am

    Lab mice are the real heroes.

  • Reply Randy Eldridge March 24, 2018 at 9:52 am

    Its the same militant theory that if your in pain one part if your body hurt something else so you won't know what hurts worse. And over stimuli the brain to where your just numb

  • Reply fennec fox March 24, 2018 at 10:10 am

    wow I wish being diabetic is just as cool as it is in the cave fish

  • Reply Vire March 24, 2018 at 10:45 am

    High level of sugar makes them blind

  • Reply John Laser March 24, 2018 at 11:38 am

    Raggedy Fins sounds like a cool rap nickname. Raggedy Finz on da track, y'all !

  • Reply claw836 March 24, 2018 at 1:42 pm

    Live longer? Hmmm

  • Reply Ark Ark March 24, 2018 at 2:17 pm

    Why does the title sound like something Filthy Frank would say?

  • Reply David Stinnett March 24, 2018 at 2:20 pm

    Can you do something on the lives of these lab rats? How do they have them modified so that their brains can be exposed to light?

  • Reply Jun March 24, 2018 at 2:36 pm

    is this a south park reference?

  • Reply Vanessa Hayes March 24, 2018 at 2:38 pm

    I feel sad that mice are still being tested upon ): I wish science wasn't so necessary for human survival

  • Reply Vanessa Hayes March 24, 2018 at 2:44 pm

    Well, this wasn't a happy episode for me. Both the studies made me sad.

  • Reply Rue Wayne Morante March 24, 2018 at 2:49 pm

    Poor animals

  • Reply Whippet Good March 24, 2018 at 2:49 pm

    So what Iโ€™m hearing is that when my doctor tells me that properly eating will help me manage my chronic pain he is a LIAR! ๐Ÿ˜‚

  • Reply Sally Philpin March 24, 2018 at 3:36 pm

    I have Ehlers Danlos syndrome, fibromyalgia, bulging discs in the neck and severe muscle spasms jn the lower back. I'm allergic to anti-inflammatory medication, instead I'm on fentanyl patches, liquid oxycodone, gabapentin, amitriptyline and paracetamol to control the pain. I would probably starve to death if hunger stopped me feeling the pain.

  • Reply Demosthenes March 24, 2018 at 4:05 pm

    Please take away the pain

  • Reply FriedEgg March 24, 2018 at 4:19 pm

    Stubbing your toe takes your mind off the pain of a head ache; therefore stubbing your toe is almost like being given a pain killer.

  • Reply Tigerous March 24, 2018 at 4:22 pm

    If Iโ€™m diabetic and I eat that fish I will be a healthy diabetic?

  • Reply THEY THREW THE BOOK AT ME March 24, 2018 at 4:35 pm

    Can I become a Superpowered Diabetic Human? ๐Ÿ˜€

  • Reply I'm listening March 24, 2018 at 4:45 pm

    Oh, great… So now I get to live with both chronic pain and starving…

  • Reply John Faria March 24, 2018 at 4:49 pm

    Wouldnโ€™t less food affect your bodyโ€™s ability to recover?

  • Reply Don Barron March 24, 2018 at 5:57 pm

    Do fish these fish eat sugar?

  • Reply ImFAULKn March 24, 2018 at 6:53 pm


  • Reply yeme March 24, 2018 at 6:58 pm

    leave the poor mices alone ๐Ÿ™

  • Reply Jess Marsh March 24, 2018 at 7:32 pm

    I'm sorry but I have chronic pain due to Ehlers Danlos Syndrome and due to the Ehlers Danlos Syndrome I have Gastroparesis which means my stomach doesn't work so can't eat. Before I had a feeding tube I was starving to death literally my body was shutting down and my chronic painnever got better it was the same or worse!

  • Reply Vincent SANTUCCI March 24, 2018 at 7:47 pm

    so we should put all diabetics in caves ? =)

  • Reply Simon's Discoveries March 24, 2018 at 8:11 pm

    I know it's important research and all but purposely giving a bunch of mice painful shots still seems sick AF to me.

  • Reply Dan McNeill March 24, 2018 at 8:50 pm

    Intermittent fasting

  • Reply Paศ™ca Alexandru March 24, 2018 at 10:20 pm

    Pain relief like… when your stomach hurts more than your thumb…?
    Or like hitting your thumb to alleviate a migraine.

  • Reply Aniss Zemri March 24, 2018 at 10:39 pm

    I wonder who tf was like ''hey let's research diabetes in cave tetra fish''

  • Reply Tim Williams March 24, 2018 at 10:49 pm

    I've been doing this for years. I suffer chronic pain. Fasting really helps and it's cheap. For maintenance I simply don't eat breakfast and don't eat lunch until after 1 pm. On bad days I only eat dinner. I've come off a laundry list of addictive meds doing this. Being hungry all the time sucks but it beats living perpetually in a drug induced fog just to not be in agony all the time.

  • Reply R3Testa March 24, 2018 at 11:01 pm

    So we're going with biological isolation NOT automatically defining a separate species again?

  • Reply avicohen2k March 24, 2018 at 11:19 pm

    The link from animals to humans is weak and if there is something there translating something like this to a wide spread treatment could take from 20 to 50 years..

  • Reply Pri Correia March 25, 2018 at 12:11 am

    Poor mice ๐Ÿ™

  • Reply Chris March 25, 2018 at 12:58 am

    As a type 1 diabetic, I wish type 1 and type 2 diabetes had different names. They're completely different diseases.

  • Reply JavaBro March 25, 2018 at 1:16 am

    Rock on, little diabetus fish. Tell us your secrets.

  • Reply John Smith March 25, 2018 at 1:28 am

    Hi Stefan Chin! That's a weird combination of names haha! Love you, bye! ๐Ÿ’‹๐Ÿ„๐Ÿ’‹๐Ÿ„๐Ÿ’‹

  • Reply thermotronica March 25, 2018 at 2:08 am

    Isnt it obvious that the cave fish get less light ? ๐Ÿคฆ๐Ÿปโ€โ™‚๏ธ

  • Reply Med Otaku March 25, 2018 at 3:21 am

    How exactly do they measure how much pain pain a mouse is feeling?

    Is there an objective Mousey Ouchie Pain Scale?

  • Reply Med Otaku March 25, 2018 at 3:23 am

    Where are all the people protesting the mouse torture?

  • Reply Empathic Dev March 25, 2018 at 3:23 am

    Why did I feel a pain in my foot after 0:45 ???

  • Reply #1 Tako March 25, 2018 at 3:41 am

    So the cure for diabetes will make us live longer?

  • Reply Violet Broregarde March 25, 2018 at 6:54 am

    Why is high blood sugar worse than low blood sugar? What damage does the sugar cause?

  • Reply Tory Alexander March 25, 2018 at 9:34 am

    WEED is fantastic for chronic pain

  • Reply Ben Tv Howman March 25, 2018 at 10:22 am

    An unreserched off the cuff Ben theory.
    In the before time and wild mice current time. When we were hunter gathers, we would not always know where our next meal was coming from.
    If we had freshly eaten our bodies can better rest up and recover without as much stress.
    We feel more pain as our bodies way of saying, stay put and rest.
    However if we have not eaten for a few days the luxury of rest does not exist. We feel some pain as not to over do it but less pain so we can get on with the job of survival.
    As I have rumitiod arthritis I have noticed in myself less pain when hungry although still excruciating it is more bearable. I never gave this any thought until now and put it down to sitting down to eat being less mobile during this time but I have noticed more pain in the few hours that follows.

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    Tone engineering pour alter somebody diamond alive automatic next examine greatest shoot.

  • Reply Alexandros X March 25, 2018 at 10:39 am

    Could the fish be explaind with ketosis? people that are in ketosis for example, dont use glucose as energy and instead use fats. so i have noticed that my blood sugar spikes when i wake up, as its normal for humans since u want to get the body going, but because i dont use the glucose as much since i am in ketosis i notice it staying at the same levels and very slowly going down during the day. So if you take a metabolism that is very slow, you could extend the whole process by a lot.

  • Reply Miss Chief March 25, 2018 at 1:28 pm

    So could diabetes be a way of overcoming lean times for humans too? Perhaps a result of irregular meals?

  • Reply Andrea Salindato March 25, 2018 at 9:28 pm

    Diabetic fish is like me

  • Reply fartzinwind March 25, 2018 at 10:25 pm

    Hard pass on this pain coping mechanism. Food > pain.

  • Reply MrFreeman012 March 26, 2018 at 1:28 am

    Hmm, who knew science could be incredibly wrong? Or at least incredibly misguided. Man, I've known about glycation for a long freaking time. How is it that actual scientists are only now realizing that high blood sugar and insulin resistance are not inherently bad?

  • Reply ZombieDogSpunky March 26, 2018 at 2:33 am

    Poor mice!

  • Reply John Smith March 26, 2018 at 4:52 am

    So they starved rats and injected them with a painful substance to see how much it hurt them. That is the most badass science ever.

  • Reply SRNF March 26, 2018 at 11:42 am

    The power of diabeatus!!!!!!

  • Reply Nico Angelo Bado March 26, 2018 at 1:39 pm

    Having the curse of diabetes in my lineage, i categorize this vid as HORROR SNUFF FILM. i can't watch to the end. LoL.

  • Reply Simon James March 26, 2018 at 4:03 pm

    Maybe solution for type 2 diabetes is to not to give sugar to humans in the first place, soo simple, but the best and simplest solutions are often overlooked

  • Reply Vilhelmo De Okcidento March 26, 2018 at 5:28 pm

    Pain Killer, like opioids, are not addictive.
    They cause Chemical Dependency.
    There is a difference.
    ~99% of people given opioids do not get addicted.
    That being said, people do get addicted to opioids, they also get addicted to food, shopping, gambling, video games, etc.

  • Reply Adam Ar-Staelin March 26, 2018 at 7:02 pm

    What about mol rates

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  • Reply Josh Sterling March 27, 2018 at 5:32 pm

    Our bodies were designed for periodic fasting ie survival

  • Reply Linn Xin Callenborn March 27, 2018 at 11:04 pm

    I feel kinda sad for the mice..๐Ÿ˜•

  • Reply Tin Cvik March 28, 2018 at 8:46 am

    Hmm, il try this next time something gets inflamed.
    Il keep you posted ๐Ÿ™‚

  • Reply Twilight Gardens presentations March 29, 2018 at 7:28 pm

    so diabetes is a starvation adaptation…interesting.

  • Reply Parakh Mody April 1, 2018 at 7:11 am

    Solving diabetes with obesity…..
    Hmmm, interesting…

  • Reply confusedwhale April 6, 2018 at 4:34 am

    So… Diabetes is a product of starvation periods?

  • Reply T4nkc0mm4nd3r April 12, 2018 at 2:03 am

    Scishow has discovered fasting reduces inflammation! Not like we've been saying this for decades…

  • Reply Akram Safirul April 15, 2018 at 9:52 am

    Or they are too hungry and powerless to react

  • Reply AmyX April 22, 2018 at 7:35 am

    New pain medications miracle! Lose weight too! Featuring, hunger strike! ๐Ÿ˜‚๐Ÿ˜‚๐Ÿ˜‚

  • Reply MtnTow July 6, 2018 at 9:07 pm

    No need to torture any mice for my benefit. Thx.

  • Reply ihartevil July 18, 2018 at 3:33 pm

    the best painkillers arent addictive its called cannabis its just illegal because it works so well advil also works its the only painkiller that can sometimes work for me but it has its consequences to my body

    it makes it so either the pain will last longer then normal or it really screws with my brain in very horrible ways (this wont happen to anybody else so i dont even want to type it)

    thx for this ha bisky vid i enjoyed knowing about this but i still say cannabis should be the number 1 painkiller

    this also explains why i want to fast before and while i am on my period

  • Reply warhawkjah September 24, 2018 at 7:16 am

    Fish diabeetus.

  • Reply Hannah Consiglio October 16, 2018 at 12:51 am

    Who is the host he's hot?

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  • Reply Gordon Lawrence April 21, 2019 at 11:59 pm

    Not only are a lot of pain killers addictive and have nasty side effects, but if you have Asperger's or Autism there is a good chance (25%-33% depending on study) that your CYP 2D6 gene does not express Cytochrome p450 2D6 which means not only that you cannot metabolise the oral form into the active form, but you also get pronounced side effects. Tramadol for me had zero effect apart from dropping my blood pressure and making me throw up every 20 minutes till it was out of my system. Codeine makes me get hot and taste metal in my mouth to the point where I cant taste food and pethidiene raises my body temperature to the point where I was put in an ice bath (in hospital), gabapentin does diddly squat apart from make me feel sick constantly, though pregabalin sort of works a bit my body will not tolerate it for more than 4 or absolute max 5 days (I'm assuming 5 but I have never pushed it much past 3).

  • Reply Tippi B June 2, 2019 at 2:36 am

    And then all the mice attacked the scientist, shouting, "We'll show ya acute pain!"

  • Reply CHARLIEM1010 July 29, 2019 at 12:23 am

    Whatโ€™s the point? Ugh

  • Reply Elizabeth Shaw August 17, 2019 at 5:03 am

    I have pernicious anemia with chronic unrelenting degenerative pain I don't feel from the hips down my forearms down all I feel is pain. My spine is also cracked from neck to tailbone and I have three discs left in my back damn. I was a ballerina with the Boston Ballet at one time. Now I am in a wheelchair and can barely use my hands I have 45 hours a week of Home Care. I don't eat for 2 or 3 days in a row simply because this disorder the printer is anemia comes from took away my appetite a long time ago because my insulin receptors don't function. I don't feel hunger very often and I'm diabetic.

  • Reply Elizabeth Shaw August 17, 2019 at 5:04 am

    I have no response to insulin so that would make me 100% insulin resistant.

  • Reply Raymond Gilbert August 21, 2019 at 8:54 pm

    Fun fact if you breed the river dwelling Mexican tetra, and their blind counterpart, the baby will look like the river dwelling version

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