Fw: News release from UT Southwestern February 28, 2001

[Guest guest]

I hope you all find this article interesting!

Martha Murdock, Director

National Silicone Implant Foundation

Dallas, Texas Headquarters

----- Original Message -----

From: " Robin Amerine " <Robin.Amerine@...>

<UTSWNEWS@...>

Sent: Wednesday, February 28, 2001 12:32 PM

Subject: News release from UT Southwestern February 28, 2001

Media Contact: Cofer

214-648-3404

brian.cofer@...

UT SOUTHWESTERN, KOREAN RESEARCHERS LINK

BICARBONATE TRANSPORT TO CYSTIC FIBROSIS

DALLAS - March 1, 2001 - Physiology researchers at UT Southwestern Medical

Center at Dallas, working with Korean researchers, have connected defects in

the transport of bicarbonate with cystic fibrosis. Their findings raise the

question about whether delivering bicarbonate to diseased tissues can

someday be used to lessen the effects of cystic fibrosis in patients and

even extend their lives.

CF is caused by mutations in a protein called CFTR. Until recently,

researchers believed cystic fibrosis was always caused by a defect in the

transport of chloride by CFTR across cells lining organs such as the lungs

and pancreas to their outer surfaces. But in recent years, researchers have

identified many mutations that do not prevent chloride transport by CFTR. In

those mutations, chloride transport is normal, but cystic fibrosis still

results in varying degrees of severity.

In previous studies, the UT Southwestern and Korean researchers found that

CFTR transports not only chloride but also bicarbonate. In this current

research published in the March 1 edition of Nature, they found that

mutations in CFTR that do not affect chloride transport actually inhibit

bicarbonate transport. They also found a correlation between the extent of

this inhibition and the severity of the disease; the greater the inhibition,

the more serious the disease.

" This tells us that bicarbonate secretion is very important for the proper

functioning of tissues affected in CF, " said Dr. Shmuel Muallem, professor

of physiology at UT Southwestern.

" We know that these tissues secrete very alkaline fluids that contain high

concentrations of bicarbonate. "

Tissues that secrete such fluids include the vas deferens, pancreas, lungs

and intestine. The acidity of those fluids in CF contributes to the

precipitation of the mucins, or secretions, that coat the surface of tissues

affected in CF and plug the ductal systems of these tissues. This acidity

also helps bind harmful bacteria to these precipitated mucins.

" Plugged ducts destroys the pancreas, and pathenogenic bacteria eventually

destroys the lungs of all CF patients, " Muallem said. " That leads to death

at an early age. "

Cystic fibrosis affects about 30,000 Americans and is caused by a defective

gene carried by about 5 percent of the population. CF patients' secretory

glands produce abnormally thick mucus that obstructs the vas deferens, the

pancreas and the airways, resulting in their destruction. The disease's

symptoms include salty-tasting skin, persistent coughing, wheezing or

pneumonia and bulky stools. Patients usually require frequent

hospitalizations and treatments, and while their life expectancy has

increased dramatically over the years, few people with the disease live

beyond their 20s.

While pointing to defective bicarbonate delivery as a culprit in causing CF

in some cases and in facilitating its symptoms, the researchers do not at

this time know how to improve delivery of bicarbonate to the surface of

affected tissues. This question remains for future research.

" If we can learn how to deliver bicarbonate to the surface of the cells, we

may be able to reduce the debilitating effects of cystic fibrosis and

lengthen the lives of CF patients, " Muallem said.

Other researchers in the study are Dr. Philip , associate professor

of physiology, and Dr. Joo Young Choi, postdoctoral research fellow, both of

UT Southwestern; and Dr. Min Goo Lee of Yonsei University in Seoul.

###

This news release is available on our World Wide Web home page at

http://www.utsouthwestern.edu/home_pages/news/