leaky blood vessel article

[Guest guest]

Forgive me if this article has been posted before (I'm presuming it's ok for me

to post articles from the met, if it's not please let me know). It doesn't

mention rosacea but I think it just shows that there may be a little light at

the end of the tunnel.......

http://www.heartlink.org.uk/headlines2001/october2001/11th-oct-2001/11thoctober2\

001story1.htmlDate: 11th October 2001 Non-leaky blood vessels grown in mice

Researchers have found a way to prompt the growth of new blood vessels that do

not leak--at least in mice. The findings could lead to improved treatments for

heart disease and diabetes-related blood vessel disease and wounds, they

suggest. Scientists have experimented with ways to promote blood vessel growth

in order to treat tissue ischemia, a temporary deficiency of blood supply due to

a blockage of a blood vessel that can occur during heart disease and poorly

controlled diabetes. They have mainly used vascular endothelial growth factor

(VEGF), a natural substance produced by the body that stimulates blood vessel

growth. However, blood vessels produced with VEGF tend to be leaky and abnormal,

and associated with tissue swelling and inflammation, the authors note. Dr.

M. Arbeit of the University of California, San Francisco, and colleagues

have managed to grow blood vessels in mice that appear to be " leakage

resistant. " The investigators say they hope the new way of promoting blood

vessel growth could improve therapy of tissue ischemia. They focused their

research on a protein called HIF-1 alpha (HIF-1a), which regulates the activity

of several genes that promote new blood vessel growth in response to low blood

oxygen levels. HIF-1a also regulates VEGF production. To test the role of HIF-1a

in promoting blood vessel growth, Arbeit's team bred a strain of mice

genetically engineered to produce high levels of the protein in their skin cells

in the presence of normal, rather than low, blood oxygen concentrations.

Writing in the October 1st issue of Genes & Development, Arbeit and colleagues

report that the number of the smallest type of blood vessels, called

capillaries, was increased in the genetically altered mice by more than half and

the increase was visible to the naked eye. In addition, the researchers found

that levels of VEGF were increased 13-fold over normal levels in the mice. And

HIF-1a did not produce swelling, inflammation or blood vessel leakage. The

investigators conclude that gene therapy prompting HIF-1a overexpression might

be useful in treating ischemia, as well as blood vessel damage and wounds that

can result from diabetes. Arbeit suggests that these findings may eventually be

applicable to humans, " either by using gene therapy to engineer HIF-1a

overexpression, or by designing drugs that will stabilize (a person's own)

HIF-1a by preventing its breakdown, " he told Reuters Health. But he said,

" additional studies will be necessary to further determine the value of

manipulation of HIF-1a function. " Source: " Reuters " .

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