"Sustaining
Life" Identifies Huge Losses to Medical
Science from the Decline and Extinction
of the World's Nature-Based Assets
Singapore/Nairobi, 24 April - A new generation
of antibiotics, new treatments for thinning
bone disease and kidney failure, and new
cancer treatments may all stand to be lost
unless the world acts to reverse the present
alarming rate of biodiversity loss a new
landmark book says.
The natural world holds
secrets to the development of new kinds
of safer and more powerful pain-killers;
treatments for a leading cause of blindness-
macular degeneration- and possibly ways
of re-growing lost tissues and organs by,
for example studying newts and salamanders.
But, the experts warn
that we may lose many of the land and marine-based
life forms of economic and medical interest
before we can learn their secrets, or, in
some cases, before we know they exist.
The new book, 'Sustaining Life', is the
most comprehensive treatment of this subject
to date and fills a major gap in the arguments
made to conserve nature.
Promising Treatment
for Peptic Ulcers Lost
A particularly illustrative example, highlighted
by the book's authors, of what may be lost
with species extinctions can be found in
the southern gastric brooding frog
(Rheobatrachus) which was discovered in
undisturbed rainforests of Australia in
the
1980s.
The frogs raise their young in the female's
stomach where they would, in other animals,
be digested by enzymes and acid.
Preliminary studies
indicated that the baby frogs produced a
substance, or perhaps a variety of substances,
that inhibited acid and enzyme secretions
and prevented the mother from emptying her
stomach into her intestines while the young
were developing.
The authors point out
that the research on gastric brooding frogs
could have led to new insights into preventing
and treating human peptic ulcers which affect
some 25 million people in the United States
alone.
"But these studies
could not be continued because both species
of Rheobactrachus became extinct, and the
valuable medical secrets they held are now
gone forever," say Eric Chivian and
Aaron Bernstein, the key authors of the
book based at the Center for Health and
the Global Environment, Harvard Medical
School.
The findings, announced
during the Business for the Environment
Summit in Singapore, come in the run up
to the 9th meeting of the parties to the
UN Environment Programme (UNEP)-linked Convention
on Biological Diversity (CBD) taking place
in Bonn, Germany later in May.
Here delegates from
close to 190 countries; business leaders,
academia and members of civil society will
look to accelerate action to reduce the
rate of loss of biodiversity by 2010.
(See Quotes by Key Players
below)
'Sustaining Life', the work of more than
100 experts and published by Oxford University
Press, has been supported by UNEP; the Secretariat
of the CBD; the UN Development Programme
(UNDP) and IUCN.
At the heart of the
book is a chapter dedicated to exploring
seven threatened groups of organisms valuable
to medicine, including amphibians, bears,
cone snails, sharks, nonhuman primates,
gymnosperms, and horseshoe crabs that underscore
what may be lost to human health when species
go extinct.
These losses include:
promising new avenues of medical research
and new treatments, pharmaceuticals and
diagnostic tests.
Experts, including the
authors, emphasize that the book's conclusions
should not be construed as a license to
harvest wildlife in a way that puts further
pressure on already threatened, vulnerable
and endangered species.
Instead they should
be a spur for even greater conservation
and improved management of species and the
ecosystems they inhabit.
Amphibians
The class Amphibians is made up of frogs,
toads, newts, salamanders and caecilians-little
known legless organisms that resemble giant
earthworms. Nearly one third of the approximately
6000 known amphibian species are threatened
with extinction.
These animals produce
a wide range of novel substances, some of
which are made only by amphibians living
in the wild, not by those in captivity.
These include the:-
Pumiliotoxins, like those made by the Panamanian
Poison Frog that may lead to medicines that
strengthen the contractions of the heart
and thus prove useful in treating heart
disease.
Alkaloids made by species like the Ecuadorian
Poison Frog, which could be the source of
a new and novel generation of pain-killers.
Antibacterial compounds
produced in the skin of frogs and toads
such as the African
Clawed Frog and South and Central American
leaf frogs.
Bradykinins and maximakinins,
made in the skin glands of species like
the Chinese
Large-Webbed Bell Toad; Mexican Leaf Frog,
and North American Pickerel Frog that dilate
the smooth muscle of blood vessels in mammals
and therefore offer promising avenues for
treating high blood pressure.
Frog glue, produced
by species such as the Australian frog,
could lead to natural adhesives for repairing
cartilage and other tissue tears in humans.
Many species of newts and salamanders, such
as the Eastern Spotted Newt, can re-grow
tissues such as heart muscle; nerve tissue
in the spinal cord and even whole organs.
As we are in evolutionary terms relatively
closely related to these species, they are
vital models for understanding how we might
someday harness our own dormant regenerative
potential.
Some frogs, such as
the Gray Tree Frog and the Chorus Frog can
survive long periods of freezing without
suffering cell damage-understanding how
these frogs do this may yield key insights
into how we might better preserve scarce
organs needed for transplant.
Bears
Nine species of bear are threatened with
extinction including the polar bear; the
Giant Panda, and the Asiatic Black Bear.
The threats to bears
are similar to those amphibians face, but
in addition many bears are
at risk because they are killed for body
parts, such as gall bladders, which can
command high prices in black markets in
places like China, Japan and Thailand.
Several medical benefits
have already arisen from the study of bears,
including the development of ursodeoxycholic
acid, found in the gall bladders of some
bear species such as polar and black bears,
into a medicine.
The substance is used
to prevent the build up of bile during pregnancy;
dissolve certain kinds of gallstones; and
prolong the life of patients with a specific
kind of liver disease, known as primary
biliary cirrhosis, giving them more time
to find a liver transplant.
Some bear species, known
as "denning" bears because they
enter into a largely dormant state when
food is scarce, are of tremendous value
to medicine as they are able to recycle
a wide variety of their body's substances.
Unlike people, who if
'bed-ridden' for a five-month period can
lose up to a third of their bone mass, bears
actually lay down new bone during the denning
period.
Bears appear to produce
a substance that inhibits cells that break
down bone and promote substances that encourage
bone and cartilage-making cells. Currently,
1000,000 deaths a year are the result of
hip fractures worldwide, a large number
of which are caused by osteoporosis.
By 2050 there will be
an estimated six million osteoporosis-linked
hip fractures globally.
Denning bears can survive
for a period of five months or more without
excreting their urinary wastes, whereas
humans would die from the build up of these
toxic substances after only a few days.
An estimated 1.5 million
people worldwide are receiving treatment
for end-stage renal disease, and more than
80,000 die each year in the U.S. alone from
this disease. By studying denning bears,
we may be able to learn how to treat them
more effectively and help large numbers
to survive.
Denning bears may also
hold clues to treating Type 1 and Type II
diabetes as well as obesity. Worldwide there
are an estimated 150 to 200 million cases
of Type II diabetes.
When produced in a non-invasive
and ethically acceptable way, without pushing
already threatened species further towards
extinction, these substances are of great
value to medicine.
Gymnosperms including pines and spruces
Close to 1,000 species
of Gymnosperms have been identified. Evolutionary
they are among the oldest of any plants
alive but many groups, such as the cycads,
are classified as endangered.
Several pharmaceuticals,
including decongestants and the anti-cancer
drug taxol, have already been isolated from
gymnosperms.
The researchers believe
many more are yet to be discovered and may
be lost if species of Gymnosperms become
extinct.
Substances from one
Gymnosperm, the Ginkgo tree may reduce the
production of receptors in the human nervous
system linked with memory loss. Thus they
may play a role in countering Alzheimer's
disease. They may also help in the treatment
of epilepsy and depression.
Cone Snails
Around 700 species make up the cone snails,
seven of which were identified only since
2004. While only four are now classified
as vulnerable, no thorough assessment has
been made in over ten years and thus current
listings may underestimate the true number
of endangered cone snail species.
For example almost 70 per cent of some 380
cone snail species surveyed had more than
half their geographic range within areas
where coral reefs, their main habitats,
are threatened.
Cone snail species may
produce as many as 70,000 to 140,000 peptide
compounds, large numbers of which may have
value as human medicines, yet only a few
hundred have been characterized.
One compound, known
as ziconotide, is thought to be 1000 times
more potent than morphine and has been shown
in clinical trials to provide significant
pain relief for advanced cancer and AIDS
patients. Another cone snail compound has
been shown in animal models to protect brain
cells from death during times of inadequate
blood flow.
It could prove a breakthrough
therapy for people suffering head injuries
and strokes and may even contribute to therapy
for patients with Parkinson's and Alzheimer's.
Other potential developments
from cone snail peptides include treatments
for urinary incontinence and cardiac arrhythmias.
Sharks
There are at least 400 species of sharks,
which, as a group, evolved in ancient seas
400 to 450 million years ago.
Many species are now threatened, with some
species, such as the Scalloped Hammerhead,
White Shark and Thresher Shark, falling
in numbers by as much as 75 percent over
the past 15 years.
Over-fishing has been
the main reason for the losses, and has
been driven by: an increased demand for
shark meat as a substitute for traditional
commercial fish catches in foods like fish
and chips; the rise in consumption of shark
fin soup; increases in by-catch, for example,
in tuna fisheries; and an increased market
for shark cartilage products for a variety
of unproved medical purposes.
?? Squalamine, a substance
isolated from sharks such as dogfish, especially
abundant in their livers, may lead to a
new generation of antibiotics as well as
treatments against fungal and protozoan
infections.
?? Studies are also
being undertaken with squalamine compounds
as possible antitumor and appetite-suppressant
substances.
?? Trials are now also
underway to see if squalamine can treat
age-related macular degeneration which can
lead to severe vision loss. The shark substance
may halt the growth of new blood cells in
the retina, which is linked to a loss of
retinal function and blindness in these
patients.
?? The salt glands of
some sharks are also being studied to gain
insight into how the human kidney functions
and how chloride ions are transported across
membranes, which may shed light on two diseases-cystic
fibrosis and polycystic kidney disease.
?? Sharks, having evolved
as some of the first creatures with a fully
functioning 'adaptive' immune system are
irreplaceable models to help us understand
human immunity. "What potential these
creatures may still hold to further our
knowledge of immunity is being rapidly depleted
with the mass slaughter of sharks and the
endangerment of sharks worldwide,"
say the book's authors.
Horseshoe Crabs
There are four species of horseshoe crabs,
with each organism possessing four eyes
and six other light-detecting organs as
well as blood that turns cobalt blue when
exposed to the air.
Because only around
ten offspring survive out of the estimated
90,000 eggs produced by a female, they are
highly sensitive to overfishing.
Once harvested and processed
to be used as fertilizer, they are now used
as bait for eel and whelk fisheries. Horseshoe
crabs are also important in the food chain,
especially for birds like the Red Knott,
which rely upon the eggs for fuel over their
16,000 km migratory journey
Horseshoe crabs also have tremendous value
to medicine.
Several classes of peptides
have been isolated from the creatures' blood
that appear to kill a wide range of bacteria.
Another pepetide from
the horseshoe crab has been developed into
a compound known as T140 which locks onto
the receptor in humans that allows the Human
Immunodeficiency Virus (HIV) to gain access
into the body's immune cells. Preclinical
trails indicate that the substance is at
least as effective as the drug AZT at inhibiting
the replication of HIV.
T140 has also shown
promise in preventing the spread of certain
cancers such as leukemia, prostate cancer
and breast cancer, and as a possible treatment
for rheumatoid arthritis.
Other cells in the blood
of horseshoe crabs can, for example, detect
the presence of key bacteria in the spinal
fluid of people suspected of having cerebral
meningitis.
The test is so sensitive
it can detect at levels of 1 picogram per
milliliter of solution- roughly the equivalent
of finding one grain of sugar in an Olympic-sized
swimming pool.
Quote from Key Players
Achim Steiner, UN Under-Secretary General
and UNEP Executive Director, said:
"Habitat loss, destruction and degradation
of ecosystems, pollution, over-exploitation
and climate change are among the powerful
and persistent impacts that are running
down the planet's nature-based capital,
including the medical treasure trove of
the world's biodiversity".
"The CBD has achieved
a great deal but it needs to achieve much
more if it is to meet the international
community's goals and objectives. We need
a breakthrough in Bonn on all three pillars
of the convention-conservation, sustainable
use, and access and benefit sharing of genetic
resources," he said.
Sigmar Gabriel, Minister
of the Environment, Germany, said: "We
are currently in the process of wiping nature's
hard drive - at a tremendous pace and without
any hope of restoring the data once it is
lost. We have to comprehend the extent of
the damage we are doing to ourselves so
that we can bring about a change of course.
In order to curb the ongoing destruction
of biodiversity before 2010 and thus reverse
the trend, we must finally adopt effective
measures at international level. This is
our overriding goal for the upcoming 9th
Meeting of the Conference of the Parties
to the Convention on Biological Diversity
in Bonn."
Ahmed Djoghlaf, UN Assistant
Secretary General and Executive Secretary,
Convention on Biological Diversity, said:
"The Earth's biodiversity, much of
which has yet to be discovered, provides
a unique opportunity to improve not only
the health of current but also that of future
generations".
"However as species
are lost so too are our options for future
discovery and advancement. Thus "Sustaining
Life" provides poignant evidence that
biodiversity loss is not merely an environmental
issue but one which affects us on a very
basic, fundamental and personal level,"
he said.
Jeffrey McNeely, Chief
Scientist at IUCN and a co-author of the
book, says: "While extinction is alarming
in its own right, this book demonstrates
that many species can help save human lives.
If we needed more justification for action
to conserve species, this book offers dozens
of dramatic examples of both why and how
citizens can act in ways that will conserve,
rather than destroy, the species that enrich
our lives.
Kemal Dervis, Administrator of UNDP, said:
"People everywhere,
and particularly the rural poor, depend
on biodiversity for food, fuel, shelter,
medicines and livelihoods. Unless we can
slow down the rapid extinction rate, which
is currently being greatly accelerated by
climate change, biodiversity loss will seriously
jeopardize our prospects for achieving the
Millennium Development Goals by 2015."
Notes to Editors
'Sustaining Life: How Human Health Depends
on Biodiversity' is published by Oxford
University Press priced $34.95 click here
On 24 April 2008
A link to the Sustaining Life web site at
Harvard Medical School Center for Health
and the Global Environment http://chge.med.harvard.edu/programs/bio/index.html
The book can also be purchased online at
Amazon.com.
The related resources can be accessed at
www.unep.org
The Convention on Biological Diversity including
details of the Bonn meeting www.cbd.int
The UN Development Programme www.undp.org
IUCN www.iucn.org
Business for the Environment Global Summit
2008 www.b4esummit.com
For More Information Please Contact Nick
Nuttall, Spokesperson/Head of Media
