Sleep Helps To Repair Damaged DNA In Neurons, Scientists Find (theguardian.com) 98
An anonymous reader quotes a report from The Guardian: Scientists have discovered that broken DNA builds up in brain cells in the daytime and repair work reverses the damage only during sleep. For an act so universal, sleep has enormous benefits. Found in organisms from flies to worms and jellyfish, it restores the body and helps learning and memory. But despite extensive research, the purpose of sleep is still mysterious. Lior Appelbaum from Bar-Ilan University and his student, David Zada, reasoned that if sleep had evolved in all organisms with a nervous system, then it might be working at the level of individual neurons.
To find out, they genetically engineered small, transparent zebrafish so the chromosomes in their neurons carried colorful chemical tags. The researchers then used a powerful, specialized microscope to watch how the chromosomes moved in the neurons, and how often DNA was broken, when the fish were awake and asleep. When the fish were awake, the chromosomes did not move much and broken strands of DNA built up in the neurons, as part of the normal wear and tear of life. If the fish were sleep-deprived, by tapping on their tank for example, some of the neurons accumulated so much genetic damage they were in danger of dying off. But, when the fish fell asleep, the picture changed. The scientists noticed that the chromosomes changed shape far more often in sleeping fish, and that DNA damage in their neurons plummeted. The same happened when the researchers added a sleep-inducing drug to the tank, causing the fish to fall asleep in the daytime. "Appelbaum said that chromosomes are constantly changing shape to allow the cells' natural repair mechanisms to mend DNA damage at different points," the report adds. "When awake, the repair work cannot keep up with the rate at which damage builds up, but in the calm hours of sleep, the repair mechanisms have a chance to get on top of the job." The study has been published in Nature Communications.
To find out, they genetically engineered small, transparent zebrafish so the chromosomes in their neurons carried colorful chemical tags. The researchers then used a powerful, specialized microscope to watch how the chromosomes moved in the neurons, and how often DNA was broken, when the fish were awake and asleep. When the fish were awake, the chromosomes did not move much and broken strands of DNA built up in the neurons, as part of the normal wear and tear of life. If the fish were sleep-deprived, by tapping on their tank for example, some of the neurons accumulated so much genetic damage they were in danger of dying off. But, when the fish fell asleep, the picture changed. The scientists noticed that the chromosomes changed shape far more often in sleeping fish, and that DNA damage in their neurons plummeted. The same happened when the researchers added a sleep-inducing drug to the tank, causing the fish to fall asleep in the daytime. "Appelbaum said that chromosomes are constantly changing shape to allow the cells' natural repair mechanisms to mend DNA damage at different points," the report adds. "When awake, the repair work cannot keep up with the rate at which damage builds up, but in the calm hours of sleep, the repair mechanisms have a chance to get on top of the job." The study has been published in Nature Communications.
Did I miss it? (Score:4, Interesting)
What are the exact effects of damaged neuron DNA?
Re:Did I miss it? (Score:5, Informative)
Stressed myelin sheathing that gets hit with amyloid plaques. Since you asked.
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From the summary, the cells may die off. Even worse, they might vote republican.
So all that DNA-wrecking radiation ... (Score:2, Interesting)
... is rather harmless, since that's normal wear and tear, and will be repaired later anyway?
I guess that explains why animals thrive in the Chernobyl exclusion zone.
I guess it's more complicated, and depends on what specific parts break that can't be repaired, and how our general lifestyle and upbringing are.
Re:So all that DNA-wrecking radiation ... (Score:5, Informative)
Radiation around Chernobyl still damages DNA & causes cancer in all mammals - not just humans.
Animals thrive in Chernobyl because there aren't any humans there. They are still having their DNA damaged by ionizing radiation though - which will give them cancer if they live long enough.
Wild animals rarely get cancer simply because they don't live long enough. Other things kill them before they're old enough for cancer to be a concern for them; predators, disease, accidents etc.
Re:So all that DNA-wrecking radiation ... (Score:4, Informative)
Poor editting, as usual (Score:2)
The story does not explain why DNA damage is a problem for a neuron and the statement " the neurons accumulated so much genetic damage they were in danger of dying off" is just thrown in as if it made sense to a layman.
It does not.
EDITORS, EDIT !
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Purpose (Score:2, Interesting)
But despite extensive research, the purpose of sleep is still mysterious
Main purpose of sleep is simply saving energy. It's hard to safely find food in the dark, so it's better to go into a power down mode instead, and expend the energy during the day. Not mysterious at all.
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If that's the purpose, it would be much better to stay awake and relaxed, so that predators couldn't attack you while asleep.
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That would depend on the energy difference between staying alert and sleeping, and the chance of getting attacked by predators, and your ability to spot them in the dark. Also depends on the sleeping patterns of the predators. Some animals (e.g. ducks) do indeed stay more alert than others.
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Except we don't really save much energy by sleeping and we expose ourselves to danger
What do you mean by "we" ?
Are you talking about humans, or about all organisms with a sleep/wake cycle ?
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Read Why We Sleep by Matthew Walker. This is an early theory that emerged that has since been debunked.
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many animals are nocturnal, and many archaic animals live in the dark depths of the sea without light, so your answer doesn't hold
That depends on how these animals evolved. Here's my hypothesis:
1) sleep evolved to save energy
2) once sleep cycle was introduced into organism, evolution modified biochemistry on various levels to take advantage of sleep/wake cycle.
3) organism becomes dependent on these modifications, even after evolving to new habitats.
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That is demonstrably false. Forcibly sleep-deprived animals (and people) die much sooner than they deplete their stored (as fat) energy reserves.
That's because they've evolved to become dependent on sleep/wake patterns. Once an organism goes to sleep every night, it makes sense to optimize their biochemistry by doing some tasks only during the sleep cycle.
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There are many functions of sleep, but conserving energy is not one of them. Sleeping is quite a handicap in terms of "staying alive" as it leaves you open to predation, yet *every* animal studied has some form of sleep. List of things that occur while you sleep is always growing, but for starters: memory consolidation, neuron connection/deletion optimization, neuron protein and contaminate cleanup, body immunity boosting / cleanup, etc. If you don't get enough sleep certain things skyrocket: heart disease
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Main purpose of sleep is simply saving energy. It's hard to safely find food in the dark, so it's better to go into a power down mode instead, and expend the energy during the day. Not mysterious at all.
This is not an actual fact. It is a simplistic speculation as to the possible "main purpose of sleep" purporting to be an incontrovertible truth. But the ubiquity of sleep to all essentially all vertebrates (at least) suggests this cannot be "the answer". Yes, you can find lots of places claiming that animal X "does not sleep" but if you dig just a little into the claim, you find that really they just have a very different sleep pattern.
There is a pretty obvious demonstration that "it mainly conserves energ
It raises interesting questions (Score:5, Interesting)
Re:It raises interesting questions (Score:5, Interesting)
A better question:
Why exactly, do you want to sleep less?
Do you think that if you spend less time asleep, you will somehow get more personal time?
Do you think that if you sleep less, you will be able to do more work? If so, who actually profits from that? Do you not realize that labor is a commodity, and like any commodity that gluts the market, it suddenly being even more available will just lower its trade value?
Why exactly do you want to sleep less?
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Well considering on weekdays if I go to bed after I get home from work at a reasonable hour I have 2 hours of time at home per workday to handle anything that needs to be done and then whatever time is left over for entertainment an additional 6 hours would be the the ability to have a life outside of work.
Of course this is assuming that if this was all of a sudden a standard thing that employers wouldn't suddenly expect an extra 6 hours of work out of people and people wouldn't suddenly be ok with working
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No, you will work longer and harder at your job, and get paid the same amount, and die younger from the increased stress and demands on your body.
Remember, this is a scenario where everyone-- and I mean EVERYONE-- is able to do this reliably/affordably. You will not be unique in having the increased time. This will have the effect of increasing the workforce's size-- at least as far as what it will do to "Dollars paid per hour of work". It will devalue labor. You will have to work more hours to compensa
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I see that you DO NOT UNDERSTAND the question AC, Or rather, do not understand the implication of the question. Here, I will spell it out for you.
A person's ability to "Have a life" in the modern capitalist world, is based on how much of a person's energy and productive potential they are willing to exchange for the materials required to feel that sense of fullfillment and enjoyment. (EG, to pay for food that actually tastes good, or for housing that isn't in a festering roach hole.)
The laws of supply and d
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A better question:
Why exactly, do you want to sleep less?
Do you think that if you spend less time asleep, you will somehow get more personal time?
Do you think that if you sleep less, you will be able to do more work? If so, who actually profits from that? Do you not realize that labor is a commodity, and like any commodity that gluts the market, it suddenly being even more available will just lower its trade value?
Why exactly do you want to sleep less?
Ah here we have the unionist work as little as possible, sleep as much as possible model. Yeah, we had a few of you back in the day. Check in, then go hide in some nook and sleep most of the day. I guess in your book, they are winning.
I've never been much of a sleeper, I've also had a lot of energy. And while some of the folk I worked with would get a bit pissed that I was willing to put in more time, it showed the revers of your cheapened commodity claim, as I was paid much more then the others. And re
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Sleep is underrated. Those who say, "Eh, I'll sleep when I'm dead" may find themselves sleeping sooner than they thought they would. The brain, heart, and body need downtime, or at least low power mode, regularly. That doesn't mean someone needs to sleep 10 hours a day though either.
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Sleep is underrated. Those who say, "Eh, I'll sleep when I'm dead" may find themselves sleeping sooner than they thought they would.
Hey - I dream solutions to problems when I'm asleep. I don't dislike it at all. My biggest issue is the concept that as a person that goes to sleep when they are sleepy, and wakes up when they are refreshed must have 8 or more hours to do so, lest they be committing slow motion suicide.
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"My single, and notedly exceptional to the rule claim obviates your statement, because I'm totally representative of the masses, except I'm not!"
Yeah... That's real enlightening. Try this one on instead.
After the second world war, women were regularly in the workplace, having migrated there during the war in order to keep their households and the nation's economy running. When the war was over, BOTH spouses were now working, which previously was not the case.
There was an initial boom is available money fr
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"My single, and notedly exceptional to the rule claim obviates your statement, because I'm totally representative of the masses, except I'm not!"
Let's make this simple, I've profited mightily off of taking advantage of people with your outlook. Your laziness makes my job easier, and brings me more money. Its okay if you do as little as possible. It's how you stick it to the man.
So go take your ignorant retired snowflake self, and stop pretending that "If everyone worked just a LITTLE harder---" because that is not what happens when EVERYONE does something.
Of course, but I know human nature. And I enjoy work. A majority of people are lazy. A majority of people actualy don't want to work at all, and are happy to approach that if possible. That is my secret sauce. People aren't going to all work harder. So I bring value, and
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Every single one of your posts so far has been all about how special and wonderful YOU are.
That is why you are a snowflake. You insist on trying to be special, and to try justifying your specialness.
I AM glad that you do acknowledge that your behavior is not indicative of the human norm, however-- It spares me having to listen to you preach about how good the world would be if everyone just worked a little harder, because it acknowledges that this is a total farce.
I am not "Lazy" as you put it though. I s
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Every single one of your posts so far has been all about how special and wonderful YOU are.
I offer an alternative. You can take it, you can ignore it, or you can get pissed off. Perhaps I am guilty of listening to people whine, bitch and moan about how terrible they have it, and mistakenly think they might want to do something different.
But yeah , I'm convinced by now, that what you are doing is bitching and moaning because that is what you want to do. Let us know how that works out for ya.
That is why you are a snowflake. You insist on trying to be special, and to try justifying your specialness.
Oh, silly lad. Here's the definition of Snowflake from Wikipedia :Generation Snowflake, or Snowflake Gen
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Do you think that if you spend less time asleep, you will somehow get more personal time? Do you think that if you sleep less, you will be able to do more work?
I would be happy to do either of those in exchange for sleep.
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Yes, I am certain that you would.
The problem is that you will not get that for your sacrifice. You will instead get to enjoy the same standard of living you currently enjoy, but with spending more time at work for your trouble, and will likely end up using the rest of the time you made this way working in the gig economy to try to get ahead (like everyone else), driving down the costs of labor through market saturation.
Those were sardonic rhetorical questions. If you think you will get those things, you a
Re: It raises interesting questions (Score:2)
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A comic on just that principle http://powernapcomic.com/ [powernapcomic.com]
Wish it would update more often, but it is what it is.
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These are mostly easy questions if you do any basic research. Caffeine suppresses your feelings of tiredness, it doesn't make you more awake. You feel and thus act more awake, but your body isn't. The body goes though roughly 90 minute cycles while sleeping. If you wake up in the middle of a cycle you're going to feel like shit. If you wake up at the end of the cycle you'll feel like you simply closed your eyes then opened them.
A nap is a period of sleep. A nap for 90 minutes and you've gone through o
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When awake, the repair work cannot keep up with the rate at which damage builds up, but in the calm hours of sleep, the repair mechanisms have a chance to get on top of the job.
What are we doing while awake that increases the rate of damage? It can't be environmental since that would presumably also be a factor while sleeping. Does *thinking* damage the brain's DNA? I don't want to even think about the implications of that...
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What are we doing while awake that increases the rate of damage?
Obsessing about getting the right amount of sleep.
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All doctors should now sue AMA (Score:4, Interesting)
Quantum mechanics observer effect? (Score:2)
That's interesting. What if the mechanism behind this action of the chromosomes moving is related in some way to quantum mechanics. For instance, what if when we are asleep we no longer have an observer effect.