Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dartmouth heart researchers discover new defect in artery growth

06.06.2006
From the beginning, arteries and veins are different in the way they branch into vascular networks, say Dartmouth heart researchers. They have identified a new defect limited to arterial development.

The discovery, reported in the June issue of Developmental Cell, upends some theories about the origins of blood vessels and could change the nature of vascular biology research that seeks to harness the mechanisms of blood vessel growth for treatment.

"This is the first demonstration of a vascular branching defect that is limited to arteries," says Dr. Michael Simons, professor of medicine and of pharmacology and toxicology at Dartmouth Medical School and chief of cardiology at Dartmouth-Hitchcock Medical Center, who led the international team. "It appears that venous and arterial endothelial cells are fundamentally different from day one. Just because they are endothelial cells doesn’t mean they are the same."

Blood vessel growth, called angiogenesis, is a double-edged sword. It aids in circulation and wound healing, but also feeds cancer tumors. Most attempts at therapeutic angiogenesis to stimulate growth of arteries have failed, Simons notes. One of the reasons may be the tendency to use venous cells to study potential therapeutic agents. "Our findings indicate that you have to choose the endothelial cell type to study to fit question you ask. So, to think about how to understand the forces of artery formation, we need to study arterial endothelial cells."

The researchers determined that an intracellular protein synectin is a key regulator of arterial growth. Using mice and zebra fish, they showed that disruption of synectin impairs arterial development. Knocking down levels in zebra fish or eliminating them in mice, they found, "resulted in profound reduction in size and complexity of the arterial network, while remarkably, not affecting venous development," the team reports. The synectin gene is expressed in every cell type in body, yet the defect is only arterial.

Homing in on the molecular process, the team found that the synectin deficient arterial endothelial cells did not make the thin membrane extensions characteristic of moving cells. Normally, a protein called Rac1 is activated to initiate the formation of the filaments, called lamellipodia. Synectin deficient arterial endothelial cells appear to have a defect that prevents the movement of the activated Rac1 protein to the cell edge to form lamellipodia.

When arteries are clogged in coronary artery disease, patients form extra arteries called collaterals to help blood bypass the obstruction. However, some patients cannot form many collateral arteries, and those patients have more serious heart disease, Simons explains. Early studies suggest that abnormal synectin gene expression may explain the absence of extra arteries in some of the patients.

Mednews | EurekAlert!
Further information:
http://www.Dartmouth.edu

More articles from Life Sciences:

nachricht Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>