Navigation Links
Researchers work to take the pressure off newborns' lungs
Date:7/27/2011

AUGUSTA, Ga. Children born with heart defects that pummel their lungs with up to three times the normal blood volume quickly find their lungs in jeopardy as well.

Georgia Health Sciences University researchers are working to take the pressure off by augmenting a natural recycling system that enables blood vessels to temporarily handle the extra workload until the heart problem is resolved.

They've found that system isn't getting enough energy to generate sufficient nitric oxide, the powerful blood vessel dilator. But drugs called PPAR agonists, already in use for adult lung injury and to lower blood glucose and lipids in diabetes, may provide the boost small, fragile blood vessels need.

"Our goal is to help protect the babies' lungs until their heart defect can be corrected," said Dr. Shruti Sharma, molecular biologist at GHSU's Vascular Biology Center. About 1 percent of newborns have a heart defect with half requiring surgery. Improved surgical and medical treatments have increased survival rates but the risk of related lung disease also can be deadly as the high blood flow turns flexible pulmonary blood vessels into narrow, rigid pipes. The result, pulmonary hypertension, also puts additional strain on the heart.

Sharma is principal investigator on a four-year American Heart Association grant to better define key steps of the recycling system and whether increasing PPAR signaling can help restore optimal functioning of the system when it's needed most.

It's known that the amino acid arginine interacts with nitric oxide synthase to form nitric oxide and while these babies have plenty of arginine, they can't access it. Studies at GHSU and elsewhere have shown that the arginine found in the endothelial cells which line blood vessels are most important for nitric oxide generation. That's where recycling comes in.

Under normal conditions, arginine helps nitric oxide synthase produce nitric oxide as well as the byproduct citrulline which interacts with two enzymes that convert it back to arginine, repeating the process anew. Sharma's early findings show that high pressures from the heart defect disrupts the cell's powerhouse, or mitochondria. That means insufficient amounts of the energy source ATP are produced, hindering the function of the molecular chaperone, HSP90, which helps the enzymes do their job.

"Upstream you can see one thing getting disrupted and downstream all the molecules it's regulating are affected," Sharma said.

That's where PPAR agonists come in. Dr. Stephen Black, a cell and molecular physiologist at the Vascular Biology Center who co-directs the Cardiovascular Discovery Institute, has shown that PPAR signaling falters in their animal model of pulmonary hypertension, impairing the cell powerhouse. In fact by blocking PPAR signaling, the researchers have produced the negative effects on the blood vessels without the heart defect.

"We hope that adding a PPAR agonist will improve mitochondrial activity and function and downstream help improve arginine recycling and nitric oxide production," Sharma said. She is retracing the recycling process to see how the agonist impacts each known step as well as the desired bottom line of improved nitric oxide production. "We're optimistic that we can get these two enzymes back to doing what they are supposed to."


'/>"/>

Contact: Toni Baker
tbaker@georgiahealth.edu
706-721-4421
Georgia Health Sciences University
Source:Eurekalert  

Related medicine news :

1. Researchers map all the fragile sites of the yeast Saccharomyces cerevisiaes genome
2. UH Case Medical Center researchers publish promising findings for advanced cervical cancer
3. Researchers discover new way to kill pediatric brain tumors
4. Researchers Who Discovered First Genes for Stuttering will Present Findings to the National Stuttering Association
5. Researchers create drug to keep tumor growth switched off
6. Urine protein test might help diagnose kidney damage from lupus, UT Southwestern researchers find
7. GUMC researchers say flower power may reduce resistance to breast cancer drug tamoxifen
8. Clemson researchers develop hands-free texting application
9. Researchers find biomarkers in saliva for detection of early-stage pancreatic cancer
10. Researchers chart genomic map spanning over 2 dozen cancers
11. Researchers discover second protective role for tumor-suppressor
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Researchers work to take the pressure off newborns' lungs
(Date:10/12/2017)... , ... October 12, 2017 , ... ... to meet the demand of today’s consumer and regulatory authorities worldwide. From Children’s ... experts and tested to meet the highest standard. , These products are ...
(Date:10/12/2017)... ... October 12, 2017 , ... Asante, a nationally ... care, have expanded their existing home health joint venture through an agreement, effective ... operating a joint venture home health company with Asante, delivering clinically integrated care, ...
(Date:10/12/2017)... ... October 12, 2017 , ... HMP , a leader ... a 2017 Folio Magazine Eddie Digital Award for ‘Best B-to-B Healthcare Website.’ Winners were ... 11, 2017. , The annual award competition recognizes editorial and design excellence across a ...
(Date:10/12/2017)... ... 12, 2017 , ... Women-owned and Grand Rapids-based workplace wellness ... in Wellness® by Best and Brightest. OnSite Wellness will be honored at the ... 7:30 a.m. to 2 p.m. at the Henry Autograph Collection Hotel, located at ...
(Date:10/12/2017)... ... October 12, 2017 , ... Vohra Chief Medical Officer ... physician colleagues, skilled nursing facility medical directors and other clinicians at various events ... Care." , "At many of these conferences we get to educate other physicians, ...
Breaking Medicine News(10 mins):
(Date:10/4/2017)... , Oct. 4, 2017  South Korean-based healthcare ... CPR training aide "cprCUBE" on Kickstarter. The device will ... during cardiac arrests with better efficiency compared to the ... offers real-time feedback on efficacy of the compression for ... campaign has a goal to raise $5,000. ...
(Date:10/2/2017)... Oct. 2, 2017  Eli Lilly and Company (NYSE: ... for the third quarter of 2017 on Tuesday, October ... on that day with the investment community and media ... The conference call will begin at 9 a.m. Eastern ... a live webcast of the conference call through a ...
(Date:9/28/2017)... -- Hill-Rom Holdings, Inc. (NYSE: HRC), will host its ... on Friday, November 3, 2017, beginning at 7:00 a.m. ... 8:30 a.m. (CDT) / 9:30 a.m. (EDT). ... and guidance for 2018, Hill-Rom executives will also highlight ... and long-range financial outlook through 2020. ...
Breaking Medicine Technology: