Proteins Spur Diabetic Mice Models To Grow Blood Vessels, Nerves

[Guest guest]

Proteins Spur Diabetic Mice Models To Grow Blood Vessels, Nerves

http://www.medicalnewstoday.com/medicalnews.php?newsid=46420

University of Utah researchers have taken a potentially powerful new

therapy for treating diabetes, peripheral vascular disease, and other

illnesses out of the test tube and into animals by demonstrating it

restores nerve and blood vessel growth in mice.

The research has particularly important implications for the

estimated 21 million Americans with diabetes, a disease that damages

both nerves and blood vessels.

The therapy involves netrins, a family of proteins that promotes

nerve development. In a study to be published this week in the

journal Science Express, the Utah researchers and colleagues from

other universities showed netrins not only accelerated blood vessel

growth in ischemic mice (those with constricted blood flow) but they

also restored blood vessel and nerve growth in diabetic mice. Dean Y.

Li, M.D., Ph.D., a cardiologist and associate professor of internal

medicine at the University's School of Medicine, is the study's

corresponding author.

" We now have a (growth) factor that attracts both blood vessels and

nerves--that's why it's unique for diabetes, " Li said. " This

demonstrates that netrins are critical for development and may be

important as a new therapy. "

Li and fellow researchers from the University of Utah and Stanford

already had shown Netrin-1, a member of the netrins family, promotes

blood vessel growth in laboratory cultures. But, until now, it had

not been demonstrated that netrins work in animals.

The researchers tested netrins and vascular endothelial growth factor

(VEGF), a gene-based therapy in Phase 2 clinical trials, in mice.

They used the same method to inject netrins and VEGF. In the mice

whose blood circulation was decreased by peripheral vascular disease,

the researchers found netrins and VEGF promoted blood vessel growth

equally well. But in the diabetic mice, netrins proved markedly

better at promoting blood vessel and nerve growth than VEGF,

according to Li.

Already in Phase 2 clinical trials, VEGF may be available as a

therapeutic gene therapy within five years. Gene therapy requires

expertise that is available in only a few medical centers. The hope

is that netrins could be more effective and may not have to be

delivered as a gene therapy, making it available to a much larger

group of patients, according to Li.

Proving netrins work in mice is a big step, but Li says it's only a

start.

" We have to find a better way to deliver the therapy, " he said.

A biopharmaceutical drug would make a good way to give the therapy.

As for any drug, to develop and get a therapy approved could take

years. If Netrins prove to be a viable therapy and resources are

committed to drug development, a netrin-based therapy could be on the

market in 10 years, Li said.

Netrins are one of four major classes of neural guidance cues, which

induce axons or nerve fibers to extend in specific directions during

development. In 2004, Li and his colleagues showed in laboratory

cultures that in addition to promoting nerve growth, Netrin-1 also

induced formation of blood vessels.