The power of venom -- and how it could one day save your life
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0:01 - 0:04How does a sea snail catch a fish?
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0:04 - 0:07I mean, it's a snail, so it's slow,
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0:07 - 0:10and the fish is not.
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0:10 - 0:12But yet, this happens.
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0:13 - 0:15Hidden under the sand is a cone snail.
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0:15 - 0:18And that orange thing you see
is kind of like a tongue. -
0:18 - 0:20We call it a proboscis.
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0:20 - 0:25It uses that to track and subdue
this unsuspecting fish. -
0:26 - 0:28In this predator-prey interaction,
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0:28 - 0:31these are clearly not
your garden variety escargots. -
0:31 - 0:34These are assassins of the sea.
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0:35 - 0:38And their weapon of choice is venom.
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0:38 - 0:42Venom, like the venom you find
in venomous snakes and scorpions, -
0:42 - 0:47these sea snails, they use their venom
to subdue fish, worms -
0:47 - 0:48and other snails.
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0:48 - 0:50And the venom of these snails,
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0:50 - 0:51it's not just one thing,
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0:51 - 0:55it's actually a cocktail
of toxic molecules -
0:55 - 0:59that are packaged and delivered
through a false tooth called a radula. -
0:59 - 1:02You can think of the radulas
as hypodermic needles. -
1:02 - 1:03Now, no need to worry,
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1:03 - 1:06these snails are practicing
good needle habits, -
1:06 - 1:08because each radula is only used once.
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1:08 - 1:11Now from your own knowledge
about venomous organisms, -
1:11 - 1:15and the keep-you-up-at-night
fish-killing video that I just showed you, -
1:15 - 1:19you might think that venom
is dangerous and all bad. -
1:19 - 1:21Well, yes and no.
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1:21 - 1:23A more accurate way of thinking of venom
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1:23 - 1:27is to think of it as both
a supervillain and a superhero. -
1:27 - 1:31In my lab, we study the evolution
of venom in these sea snails -
1:31 - 1:33as a force for good.
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1:33 - 1:34Sounds like a stretch,
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1:34 - 1:36or maybe even snake oil,
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1:36 - 1:37but actually,
-
1:37 - 1:40while there are snakes involved,
the product is legit. -
1:40 - 1:42One reason the venom product
is so successful -
1:42 - 1:47is that it transforms a physical warfare
into a biochemical one. -
1:47 - 1:52Where usually the predator-prey
interaction is one of brute force, -
1:52 - 1:54venom takes it to a molecular scale.
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1:54 - 1:56And it's not size that matters,
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1:56 - 1:58but the mixture of your venom arsenal.
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1:58 - 2:01The chemistry of the toxins
in your arsenal -
2:01 - 2:04is what's going to enable David
to conquer Goliath. -
2:04 - 2:07And in our scenario,
David is clearly the snail. -
2:07 - 2:11Another feature of venom
that makes it so successful -
2:11 - 2:15is that the toxins work
with the precision of a Swiss Army knife. -
2:15 - 2:16And so these toxins,
-
2:16 - 2:20they come for strongholds
that help an organism to function. -
2:20 - 2:23So they target blood, brain and membranes.
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2:23 - 2:26Whether it's snail venom or snake venom,
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2:26 - 2:29they each have components
that can do things -
2:29 - 2:31like cause your blood to clot,
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2:31 - 2:32what we call "hemotoxic."
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2:32 - 2:36Or they cause neurons in your brains
to not function normally, -
2:36 - 2:38what we call "neurotoxic."
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2:38 - 2:42Or they have toxins that will poke holes
into the membranes of your cells, -
2:42 - 2:46causing them to rupture
and, basically, explode, -
2:46 - 2:47what we call "cytotoxic."
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2:47 - 2:50Cellular explosion, people.
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2:50 - 2:53Now, if that is not all powerful
and all present, -
2:53 - 2:54nothing is.
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2:54 - 2:56Now a little about me,
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2:56 - 2:58and why I'm so obsessed with venom.
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2:59 - 3:00I grew up in New York City
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3:00 - 3:03with forced access
to the Natural History Museum. -
3:03 - 3:05I say "forced access,"
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3:05 - 3:06because I'm one of five kids,
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3:06 - 3:10and my parents used museums
as a form of childcare. -
3:10 - 3:11There were two rules:
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3:11 - 3:13Don't lose anybody
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3:13 - 3:15and meet Mom and Dad
at the African elephants -
3:15 - 3:17at 5:30, when the museum closes.
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3:18 - 3:23Those totally unsupervised days
running through the halls of the museum -
3:23 - 3:26were full of adventure and exploration.
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3:26 - 3:29And that's how I feel
when I'm studying venom. -
3:29 - 3:30It's a scientific adventure.
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3:30 - 3:36We're boldly exploring this entity
that connects nature and humanity. -
3:36 - 3:38Another reason
that I'm obsessed with venom -
3:38 - 3:40is because of its duality.
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3:40 - 3:43When you inject the components
of a venom arsenal into an organism, -
3:43 - 3:46it can kill or it can cure.
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3:46 - 3:48At a molecular level,
several things can happen. -
3:49 - 3:52You saw one thing, paralysis in the fish.
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3:52 - 3:55Now that was happening
because the toxins in the venom -
3:55 - 3:58were attacking how the fish's cells
communicate with each other, -
3:58 - 4:00preventing it from swimming away.
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4:00 - 4:03Are there other things
that I would like to use venom to attack? -
4:04 - 4:05For sure.
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4:05 - 4:07And one of those is cancer.
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4:07 - 4:09Cancer tumors are cells.
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4:09 - 4:10And like all cells,
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4:10 - 4:13they communicate with themselves
and their environment around them. -
4:13 - 4:15So we would like to find venom components
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4:15 - 4:19that are very good at disrupting
how the tumor cells communicate. -
4:19 - 4:24Similar to how the venom disrupted
how the fish cells communicated -
4:24 - 4:26and the fish couldn't swim away.
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4:26 - 4:30In my lab, we study cancer
as a channelopathy. -
4:30 - 4:33What this means is, basically,
we're looking for venom components -
4:33 - 4:37that will target channels
that are overexpressed in tumor cells -
4:37 - 4:39versus normal cells.
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4:39 - 4:41The cancer that we're most
focused on right now -
4:41 - 4:42is liver cancer.
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4:42 - 4:45And that's because since the 1980s,
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4:45 - 4:48the death rate of liver
cancer has doubled, -
4:48 - 4:50and it's an emerging threat in the US.
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4:50 - 4:52In a screen in which we had cervical,
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4:52 - 4:55neuroblastoma, prostate
and liver cancer cells, -
4:56 - 4:58we found a compound from a terebrid snail
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4:58 - 5:01that seems to attack liver cancer cells,
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5:01 - 5:05and only liver cancer cells,
and none of the others that were tested. -
5:05 - 5:08And then, when we took this compound
and we injected it into mouse models -
5:09 - 5:11that were expressing liver cancer cells,
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5:11 - 5:14it significantly inhibited
the growth of the tumors. -
5:14 - 5:16We're not quite sure how this works yet,
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5:16 - 5:18we're still investigating the mechanism
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5:18 - 5:21and how we can make
this compound more effective, -
5:21 - 5:23so you can't rush out to the pharmacy
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5:23 - 5:27and order up a killer snail
liver-cancer therapy treatment. -
5:27 - 5:28Not yet.
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5:28 - 5:30Basically, what we think is happening
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5:30 - 5:34is that the compound is blocking
a specific channel, -
5:34 - 5:37prohibiting the transmission
of a specific chemical -
5:37 - 5:39that leads to downstream signaling
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5:39 - 5:43that enables the tumor to multiply
and draw blood to itself. -
5:43 - 5:46What we're doing in studying
the components of venom -
5:46 - 5:49to find treatments for human
diseases and disorders, -
5:49 - 5:50is not new,
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5:50 - 5:53it's what we call natural
products drug discovery, -
5:53 - 5:55and it's been happening for centuries,
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5:55 - 5:57and in cultures all over the world.
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5:57 - 5:59Venoms are not only giving us
cool new compounds, -
5:59 - 6:02but they're also giving us
new ways of thinking -
6:02 - 6:05about how we treat
human diseases and disorders. -
6:06 - 6:07And I'll give you three examples.
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6:07 - 6:10The first is from killer
snails, of course. -
6:10 - 6:14And so the first drug from these snails
that is on the market -
6:14 - 6:17is called ziconotide, or Prialt,
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6:17 - 6:21and it's used to treat chronic pain
in HIV and cancer patients. -
6:21 - 6:24Prialt is a nonaddictive pain therapy.
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6:24 - 6:28Three magic words when you think
about how we're treating pain currently. -
6:28 - 6:32We're using things that have
a huge cost of addiction. -
6:32 - 6:33So think of morphine
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6:33 - 6:36or think of any of your favorite
opioid out there. -
6:36 - 6:37What the snails have done
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6:37 - 6:41is they've shown us a way to treat pain
without the addiction, -
6:41 - 6:43which is huge.
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6:43 - 6:46The next example comes
from the Brazilian pit viper. -
6:46 - 6:50From these snakes, we've derived
a compound called captopril. -
6:50 - 6:53Captopril is used to treat
high blood pressure, -
6:53 - 6:55and captopril is a breakthrough drug.
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6:55 - 6:58But not only in and of itself,
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6:58 - 7:01but because it advanced
a whole class of drugs, -
7:01 - 7:03what we know as ACE inhibitors,
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7:03 - 7:06which are the most commonly [prescribed]
for treating hypertension -
7:06 - 7:08and heart failure.
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7:08 - 7:11The last example is from the Gila monster.
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7:11 - 7:15And this is a really exciting example
of understanding the ecology -
7:15 - 7:17of these organisms,
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7:17 - 7:19and pairing it with efficient
drug discovery. -
7:19 - 7:21And Gila monsters are binge eaters.
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7:21 - 7:24So when they bite into a large meal,
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7:24 - 7:27they release things in their venom
that lower blood sugar. -
7:27 - 7:31So what's the drug that you think
we found from the Gila monster? -
7:31 - 7:35A compound that is used to lower
the blood sugar in diabetic patients. -
7:35 - 7:37Now these are three marvelous examples,
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7:37 - 7:39but we've just scratched the surface.
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7:39 - 7:42There's so much more venom
out there for us to study. -
7:42 - 7:46In fact, we think that 15 percent
of all the animals on the planet -
7:46 - 7:47are venomous.
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7:47 - 7:49And I think this is a low estimate,
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7:49 - 7:52given the fact that we haven't surveyed
all the animals on the planet. -
7:52 - 7:55But nature seems to have found
something that she likes, -
7:55 - 7:58and she's repeated it
over and over and over again, -
7:58 - 8:01leading to the vast array of animals
that we see around us -
8:01 - 8:03and all throughout the tree of life.
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8:03 - 8:06So whether we're talking
about my fave, killer snails, -
8:06 - 8:07or jellyfish,
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8:07 - 8:10or the larvae of butterflies and moths,
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8:10 - 8:13or platypus or slow lorises,
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8:13 - 8:16whether by sea, land or air,
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8:16 - 8:19you're sure to encounter
a venomous creature. -
8:19 - 8:20Remember when I told you
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8:20 - 8:24that venom can be both
a superhero and a supervillain, -
8:24 - 8:26and you doubted me?
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8:26 - 8:27Mhm.
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8:27 - 8:30We're in a race to harness
all of this venom goodness -
8:30 - 8:33before we lose the vast majority
of animals on our planet. -
8:33 - 8:35It's a holistic process.
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8:35 - 8:39You can't have the therapeutic treatments
without having the animals. -
8:39 - 8:41And you can't have the animals
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8:41 - 8:43without having their ecosystems.
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8:43 - 8:45So for me and the snails,
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8:45 - 8:47what it means is
we have to save the oceans. -
8:47 - 8:50And because venomous animals
are found everywhere, -
8:50 - 8:52we basically have to save the planet.
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8:52 - 8:54So do it for the venomous animals,
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8:54 - 8:55if you don't want to do it for yourself.
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8:56 - 8:57And who knows,
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8:57 - 9:00some day, snail venom
might just save your life. -
9:01 - 9:02Thank you.
- Title:
- The power of venom -- and how it could one day save your life
- Speaker:
- Mandë Holford
- Description:
-
Venom can kill ... or it can cure. In this fascinating talk, marine chemical biologist Mandë Holford shares her research into animal venom, from killer sea snails to platypuses and slow lorises -- and explores its potential to one day treat human diseases like cancer. The mechanism behind this powerful substance is still mysterious, Holford says, but: "Someday, snail venom might just save your life."
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 09:16
marialadias edited English subtitles for The power of venom -- and how it could one day save your life | ||
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Krystian Aparta edited English subtitles for The power of venom -- and how it could one day save your life | ||
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Ivana Korom edited English subtitles for The power of venom -- and how it could one day save your life |