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Biodiversity
Loss - It Will Make You Sick
"Sustaining
Life" Identifies Huge Losses to Medical Science from the Decline
and Extinction of the World's Nature-Based Assets
Singapore/Nairobi, 24 April 2008 - 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, 740,000 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."
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