[fcb-l] WONDER DRUG TO STOP BLINDNESS
don.moore48 at comcast.net
Thu Jul 26 11:43:41 EDT 2012
WONDER DRUG TO STOP BLINDNESS
Thursday July 26,2012
A CURE for blindness has moved a major step closer after a simple chemical
injection in the eye was shown to restore sight.
The breakthrough gives hope to millions of people suffering from inherited
and age-related blindness.
Scientists in the US used the technique to bring back sight to blind mice.
They are now developing an improved version of the chemical, known as AAQ,
which they believe could be just as effective on humans.
Dr Russell Van Gelder, a leading eye expert at Washington University in
Seattle who helped in the pioneering research, said: “This is a major
advance in the field of vision restoration.”
Wonder drug AAQ works by making normally “blind’’ cells in the retina
sensitive to light.
The researchers hope it will defeat the genetic disease retinitis
pigmentosa – the most common inherited form of blindness – as well as
age-related macular degeneration (AMD).
A quarter of all over-60s in Britain and more than half of over-75s are hit
It is the UK’s leading cause of blindness, affecting at least half a million
people. The number of sufferers is expected to rise rapidly as the
population ages. Currently there are few treatments – and no cure – for the
It is caused by the deterioration of the cells in the macula, the part of
the retina used to see straight ahead, robbing sufferers of their central
The more common “dry” form affects the eyes gradually, sometimes over many
decades. But one in seven of those with dry AMD will develop the more
serious wet form and lose their central vision almost immediately.
The number of people being struck by AMD is set to soar by the end of the
decade. A recent study predicted a rise in NHS cases from 26,000 to 71,000
In both AMD and the genetic disease retinitis pigmentosa, light-sensitive
cells in the retina die, leaving the eye without working photo-receptors.
But researchers say that when light activates the chemical AAQ, it switches
on brain cells in a similar way to the light-sensitive cells in working
retinas. It means that the brain registers light received through the eye.
Steve Winyard, of the Royal National Institute of Blind People, said last
night: “This is very interesting research.
“RNIB welcomes the continuing research into treatments that could one day
help to restore some people’s vision, particularly as it is predicted that
by 2050 the number of people with sight loss in the UK will double to nearly
“However, clearly it is still at an early stage and more extensive trials
are needed to confirm the safety and effectiveness of this kind of
After being injected into the eye, AAQ eventually wears off. But the US team
believes it offers a safer alternative to other experimental ways for
restoring sight, such as gene or stem cell therapies which permanently
change the retina.
It is also less invasive than implanting light-sensitive chips in the eye.
The study’s co-author, Professor Richard Kramer of California University in
Berkeley, said: “The advantage of this approach is it is a simple chemical
which means that you can change the dosage.
“You can use it in combination with other therapies or you can discontinue
the therapy if you don’t like the results.
“As improved chemicals become available you could offer them to patients.
You can’t do that when you surgically implant a chip or after you
genetically modify somebody.”
New versions of AAQ which activate neurons, or nerve cells, for days rather
than hours are now being tested.
More information about the fcb-l