Diving for Cures

  • Researchers are hoping to find cures underwater in corals and sponges. (Photo courtesy of NOAA)

Making medicine from things
found in nature isn’t a new
idea. Think, aspirin – which
originally came from the bark
of willow trees. Now drugs
derived from ocean animals are
slowly making their way onto
shelves. Samara Freemark talks to a researcher
who helps get them there:

Transcript

Making medicine from things
found in nature isn’t a new
idea. Think, aspirin – which
originally came from the bark
of willow trees. Now drugs
derived from ocean animals are
slowly making their way onto
shelves. Samara Freemark talks to a researcher
who helps get them there:

Mark Slattery is trying to find a cure for cancer. Slattery is a pharmacology professor at the University of Mississippi. But he doesn’t really spend much time in the lab. Instead, he’s usually in a wetsuit, scuba diving off the coasts of places like Guam and Antarctica.

He’s taking samples from tens of thousands of corals and sponges. He’s looking for that one special species that might make a chemical that could cure disease. He calls it, ‘diving for cures.’

“In many ways, it’s like going out and playing your super lotto or whatever. You pick your eight numbers and you see if you hit or not.”

The idea is pretty simple. A third of the medicines on shelves today were derived from plants and animals that live on land. So ocean researchers got to thinking that the organisms they studied probably also produced a lot of useful chemicals.

Take corals and sponges. They can’t run away from predators, so instead they squirt out chemicals that poison the fish that try to take a bite out of them. Marc Slattery says those toxins are bad for the fish – but they could be good for people.

“Those particular compounds that tell a fish “not today” are the same ones that might tell the AIDS virus “you can’t replicate” or tell a cancer cell “you’re dead” or those kinds of things.”

So Slattery and other researchers like him clip off bits of sponges and corals. When they get back to the lab they extract the chemicals, which is a nice way of saying…

“Stick it in a blender with methanol and ethyl acetate and hexanes and all those sorts of things you used in organic chemistry lab, and you throw away the dead sponge, and the tarry residue that’s left is sort of the biochemistry that came out of that sponge.”

“So you make a sponge smoothie?”

“Exactly.”

Once they’ve extracted the chemicals, researchers test to see if they have any human application. If a compound looks promising, it moves on to clinical trials. Those trials can take decades, which is why ocean-derived drugs are only now starting to hit the market. So far only two have been approved for use in the United States: a painkiller, and a cancer drug marketed by Johnson and Johnson.

I wondered how ocean conservationists felt about diving for cures. So I called up Sandra Brooke. She studies corals at the Marine Conservation Biology Institute. Brooke says she does worry that diving for cures could lead to over-harvesting.

“Once something becomes valuable to people, there’s a resistance to closing access to it. It becomes harder to regulate it.”

But she says corals are under much greater and much more immediate threats. The biggest culprit is industrial trawling. That’s when fisherman scrape reefs off the ocean floor so they can get to the fish.

“It’s just like the clear cutting of the forest, but on a much vaster scale. They are deliberately mowing down these deepwater coral ecosystems that are thousands and thousands of years old – some of the oldest animals ever measured. And that’s not going to come back – not in our lifetimes, not in many lifetimes.”

There’s also the fact that oceans are changing as the climate does. Those changes mean corals are becoming weaker. Marc Slattery thinks he might be seeing that in a Pacific reef he’s been studying for fifteen years.

“When we went back and started looking at it, we noticed that there was a change in the chemistry through time. As things have heated up on the reefs, there’s a physiological effect that has cascaded down into their ability to produce the chemistry we’re used to seeing. Early on it was so apparent, it was always there, and now they seem to be able to produce less of it.”

That’s means that today the cure for cancer might be out there in some coral reef, but it could be gone tomorrow.

For The Environment Report, I’m Samara Freemark.

Related Links

Coral Conservation in the Caribbean

  • The island of Bonaire is somewhat of an anomaly in the Caribbean due to its remarkably preserved coral reefs (Photo by Ann Dornfeld)

Scientists say nearly half of the coral reefs in the US are in bad shape.
Many are dead. The situation is similar in much of the world. But not
everywhere, as Ann Dornfeld found on the Caribbean island of Bonaire:

Transcript

Scientists say nearly half of the coral reefs in the US are in bad shape.
Many are dead. The situation is similar in much of the world. But not
everywhere, as Ann Dornfeld found on the Caribbean island of Bonaire:

(sound of waves on shore)

Jerry Ligon was working as the on-board naturalist on a small Caribbean
cruise ship when he first saw Bonaire.

“And I saw how clear the water was. And I’d been able to compare, during
my stint on the cruise ship, other islands in the Caribbean, and I realized
how special Bonaire was. So that was at the end of my contract, so I
decided to stay here. And I’ve been here for 15 years!”

It’s wasn’t just the clarity of Bonaire’s water that made Ligon stick around. It
was the remarkably healthy coral reefs that lay beneath the waves.

“I can even talk to divers who come to Bonaire and they say, ‘What
fantastic diving!’ and they remember, ‘This is how the way it was in Cayman
Islands 25 years ago!'”

Ligon says the Cayman Islands might have even had more impressive
reefs than Bonaire’s back in the day. But coral throughout the US and
Caribbean has been in sharp decline for decades.

So how do Bonaire’s reefs remain intact?

Ramón de León is the manager of the Bonaire National Marine Park. He
says the island has an advantage in that it has no industries to pollute the
water.

The island is mostly undeveloped, which means relatively little farm and
lawn fertilizer run-off that can create marine algae blooms. And cool
upwellings in the region help balance the rising ocean temperatures. Warm
oceans can cause coral bleaching, which often kills the coral animal.

But de León says Bonaire really owes its healthy reefs to its history of
conservation laws. They date back to an era when such policies were rare.

“Bonaire start to protect sea turtles and turtle nests in 1961, back when
everybody was promoting sea turtle soups and nailing shells in the walls.”

By the end of the 1970s, Bonaire had banned spear fishing and made it
illegal to damage coral. For years, divers have been required to pay a
sizeable fee and take an orientation course before they’re allowed to dive
on the island. That helps them avoid touching the coral, which can kill it.

De León says the island still allows too much fishing. So several years ago,
he told the island’s fishermen they needed to choose a no-take zone to let
the reefs recover.

“I refuse to decide myself. I give the fishermen some prerequisites that they
have to have to close, and they chose which area. Is not my number-one
option, but is their number-one option. So I have to respect that.”

De León says because the fishermen chose the no-take zone, something
important happened. Compliance is high.

For all of Bonaire’s success in coral conservation, there are still some
problems. De León says its reefs suffer from leaky septic tanks and boat
pollution. And there are few of the large predator fish that used to maintain
population balance on the reefs.

But the island is a haven for researchers like Mark Patterson. He designs
underwater robots at Virginia Institute of Marine Sciences.

Last year he led a NOAA expedition to use robots to map Bonaire’s reefs.
He says the island’s reefs are valuable as a baseline by which other reefs
can be judged.

“If you’re an up-and-coming marine scientist and you go to a lot of the coral
reefs on the planet now, you might think that all coral reefs have always
look like this. And they haven’t! So the fact that we’ve got some pristine
reefs left is very important, and we’ve got to work very hard to protect them
because it shows us how the ecosystem should look and used to look
around the planet before things started to go downhill.”

For The Environment Report, I’m Ann Dornfeld.

Related Links

Artificial Reefs: A Help or a Hindrance?

Artificial reefs are being built in the Great Lakes to attract fish.
Sport fishing groups like them because the reefs make it easier to catch
fish. However…the Great Lakes Radio Consortium’s Lester Graham reports
some conservationists are concerned the artificial reefs could destroy
natural habitat: