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When you think of narcolepsy, you probably think of people falling asleep at seemingly
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random times, but it's actually much more than that.
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It causes hallucinations, insomnia and sleep paralysis and can be triggered by moments of joy.
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Oh, and the key to understanding it came from studying man's best friend.
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Narcolepsy is a neurological disorder where your brain loses its ability to control its sleep-wake cycle.
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This includes symptoms like cataplexy, a condition that causes uncontrollable muscle weakness
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or paralysis which is often triggered by excitement or laughter, and hypnagogic hallucinations,
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which is basically when you start to dream before you fall asleep.
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That's great.
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It would be white wine.
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Hello my name is Emmanuel Mignot, I'm a professor at Stanford.
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I'm a medical doctor and a researcher and I've been working for 30 years on a sleep disorder called narcolepsy.
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Narcolepsy is a very strange disorder...
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So initially people thought it was even a type of seizure.
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But then when people looked they said no, it's not seizures, they are more sleeping.
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But narcolepsy isn't really about falling asleep, it's about not being able to stay
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awake - and the role of a specific neuropeptide made in a very small region of the brain.
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The region that's called hypothalamus which is just above the optic nerve.
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So very important, very primitive part of the brain that regulates sleep, appetite, very basic physiology.
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And these cells that produce hypocretin are all there.
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Hypocretin, also known as orexin, is a neuropeptide that is responsible for keeping you awake.
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Once released, hypocretin travels throughout the brain activating other cells, like those
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responsible for creating things like dopamine, histamine, serotonin and norepinephrine.
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These brain cells then start to fire more, releasing their respective chemicals which,
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in turn, further stimulate your brain.
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And the other thing it does is and that's a little bit less understood but it can also control your dreaming.
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So is that when this chemical is absent, dreams come too strongly and too fast.
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And that's why you have all these weird symptoms of dreaming too much and the dreams are almost
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real and sometimes you are paralyzed at the wrong time because you are paralyzed during dreaming.
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So the two main function of this chemical is: one is to stay awake voluntarily and the
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second one is to control your dreams so that your dreams don't come too fast into wakefulness.
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And this chemical is very important...and when it's not there you have narcolepsy.
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It took me 10 years to figure out the cause of narcolepsy in terms of losing the hypocretin cells.
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Then it took me 15 years to figure out why the cells were missing.
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This is the Pandemic H1N1/09 virus, but you may know it as the swine flu.
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Dr Mignot and team noticed that during the 2009 swine flu pandemic, there was a significant uptick in narcolepsy cases.
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And that I have to say we discovered by chance that it seems to be the flu that triggers this abnormal reaction…
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In fact we discovered that there is a piece of this 2009 swine flu that looks very much like hypocretin.
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And then instead of attacking just the flu the cells start to attack hypocretin and then
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it kills the cells that produce it.
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And then once the process is started then it starts to be more and more inflamed and
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then it kills the hypocretin cell thinking is the flu infected cells and then you don't
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have anymore hypocretin cells and then you have narcolepsy for the rest of your life.
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The immune system attacking hypocretin producing cells is why many people categorize narcolepsy
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as an autoimmune disease.
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But this response doesn't happen to everyone who gets the flu virus.
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In fact, I like to say that to develop narcolepsy, you have to have a series of bad luck.
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You know because really your immune system has to be primed a certain way and you have
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to get the flu at a certain time together with a certain immune background to genetic
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background to really develop narcolepsy.
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So it's like a perfect storm to develop narcolepsy.
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But humans aren't the only ones to develop narcolepsy.
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It can affect dogs and as well as horses and bulls.
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In fact, by studying narcolepsy in dogs, Dr Mignot and others were able to initially make
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the connection between hypocretin and staying awake.
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And at the end you know one breakthrough was actually which found a family of dachshund with narcolepsy.
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I still remember the dog.
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It was Fritz.
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Narcolepsy in dogs is a genetic disease, so researchers were able to map the mutation
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that caused narcolepsy in dog families, notably in Fritz, and found a very important mutation.
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And then finally we discovered that this gene was a mutation in a receptor for a chemical called orexin, or hypocretin.
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From there Dr Mignot and his team were able to focus their study of narcolepsy in humans
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and eventually come to their breakthrough connecting it to the hypothalamus and the swine flu.
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Fritz was really key.
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Thanks Fritz...good dog.