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Health is the most valuable thing we have in life, but we tend to forget that until we lose it.
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We're living longer than ever before, which is great,
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but an unforeseen consequence of this is that we also spend a larger and larger portion of our lives being sick.
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Getting old currently means spending more time in pain.
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So scientists are trying to shift the attention of the medical community from optimizing lifespans to optimizing healthspans,
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the part of our lives during which we're disease free.
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To do this, we need to attack the root cause of almost all bodily defects: aging itself.
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Unbeknown to most people, the science of aging has made enormous progress In the last few years,
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with human trials about to begin in the near future.
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Let's look at three examples of discoveries that might benefit people who are alive right now
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INTRO
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1: senescent cells.
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Your cells have an expiration date.
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Each time one of your cells divides, it copies its chromosomes.
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Because of the way this works, they lose a tiny bit of DNA at the ends.
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This could be catastrophic, so to protect themselves we have long segments of DNA called telomeres
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that sort of act like the stiff bits at the end of shoelaces, but they shrink with every cell division.
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In some cells, after a number of divisions the telomeres are gone, and the cell becomes a zombie, a senescent cell.
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Senescent cells stay around and don't die. The older you get the more of them are inside you.
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They harmed tissue around them and are linked to many diseases that accompany old age like diabetes and kidney failure.
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But what if you could kill them off?
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Scientists genetically engineered mice so that they could destroy their senescent cells as they pleased.
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Older mice without senescent cells were more active. Their hearts and kidneys worked better, and they were less prone to cancer.
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Overall, they lived up to 30 percent longer and in better health than average mice.
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Since we can't genetically engineer all the cells in the human body, we need to find another way to get rid of our senescent cells.
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But how do we kill them without harming healthy cells?
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Most cells in the body commit a programmed cell suicide when they're damaged, but senescent cells don't.
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It turns out that they underproduce a protein that tells them when it's time to die.
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So in a late 2016 study, mice were given an injection of this protein.
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It killed 80 % of all their senescent cells, while causing almost no harm to healthy cells.
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The treated mice became generally healthier and even regrew lost hair.
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As a result, there are a number of new companies looking at treatments involving senescent cells and the first human trials will start soon.
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2: NAD+
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Cells are made of hundreds of millions of parts.
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They're the structures, machines, messages, and the catalysts that make reactions happen.
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All these parts constantly need to be destroyed, cleaned up, and rebuilt.
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As we age, this process becomes less effective and so parts become crumpled, bunched up,
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or are removed slower, or they are no longer produced in the quantities we need.
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One of these parts is NAD+, a coenzyme that tells ourselves to look after themselves.
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At age 50, we only have about half as much in our bodies as we do at age 20.
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Low amounts of it are linked to a whole bunch of diseases from skin cancer to Alzheimer's, cardiovascular disease, and multiple sclerosis.
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But NAD+ can't enter cells so we can't get it as a pill.
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But scientists notice that other more flexible substances could enter cells and would then turn into an NAD+ inside.
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In 2016, multiple trials on mice showed that they boosted the multiplication of skin, brain, and muscle stem cells.
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They were rejuvenated, had a higher ability to repair their DNA, and had a slightly increased lifespan,
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This even got NASA interested,
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which is looking for a way to minimize the DNA damage astronauts would be exposed to from cosmic radiation on Mars missions.
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There are human trials being planned right now,
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but it's too soon to say if this will boost our healthspan or even lifespan.
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But NAD+ is a serious candidate and could become the first human anti-aging pill.
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3: stem cells
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Stem cells are like cell blueprints that sit at various places in the body and copy themselves to produce a steady flow of fresh young cells,
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but they decline as we age and so we decline too.
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Without new parts, human bodies break.
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In mice, scientists observed that as the stem cells in their brains disappeared, they started to develop diseases
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So they took stem cells from baby mice brains and injected them directly into the brains of middle-aged mice,
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more specifically the hypothalamus, a polyp that's involved in regulating a lot of bodily functions.
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The fresh stem cells reinvigorated older brain cells by secreting micro RNAs that regulated their metabolism.
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After 4 months, brain and muscles worked better than those of untreated mice and on average, they lived ten percent longer.
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Another study took stem cells from mice embryos and injected them directly into the hearts of older mice.
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As a consequence, they had improved heart function, could exercise 20% longer, and weirdly enough their hair regrew faster.
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Conclusion
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What all of this tells us is that there is not a single magic bullet with which to cure aging.
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It requires a complex array of different therapies.
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We can kill off senescent cells to clear away the junk,
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give ourselves fresh new stem cells to fill the gap, all while regulating the metabolism of the other cells using medication.
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This video comes with a big caveat. After all, these studies have been carried out on mice.
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There's no guarantee the same therapies would work in us to the same extent, but they are proof of concepts.
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To learn more about how we can modify our own healthspan, we need human trials.
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We've only covered a tiny part of the research that's being done right now, and only scratched the surface of these ideas.
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The field of healthspan extension needs more attention and funding.
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If it gets it, all of us might enjoy growing old without pain
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If you now want to support the research on aging directly, you can do so at lifespan.io,
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a community of people actively supporting the scientists working to cure aging.
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Check them out to learn about the latest advances and visit their blog or group on Facebook.
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The lifespan team also kindly supported the creation of this video with a donation and their expertise.
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If you want to help us make more of our videos, you can do so on patreon.com.9081
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