Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny particles can deliver antioxidant enzyme to injured heart cells

17.11.2009
Researchers at Emory University and the Georgia Institute of Technology have developed microscopic polymer beads that can deliver an antioxidant enzyme made naturally by the body into the heart.

Injecting the enzyme-containing particles into rats' hearts after a simulated heart attack reduced the number of dying cells and resulted in improved heart function days later.

Michael Davis, PhD, is presenting the results Sunday evening at the American Heart Association Scientific Sessions in Orlando. Davis is assistant professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

The enzyme in the particles, called superoxide dismutase (SOD), soaks up toxic free radicals produced when cells are deprived of blood during a heart attack. Previously scientists have tried injecting SOD by itself into injured animals, but it doesn't seem to last long enough in the body to have any beneficial effects.

"Our goal is to have a therapy to blunt the permanent damage of a heart attack and reduce the probability of heart failure later in life," Davis says. "This is a way to get extra amounts of a beneficial antioxidant protein to the cells that need it."

The simulated heart attacks caused a 20 percent decrease in the ability of the rats' hearts to pump blood that was completely prevented by the particles, he says.

The particles are made of a material called polyketals, developed by Niren Murthy, PhD, assistant professor of biomedical engineering at Georgia Tech and Emory. The polyketals encase the enzyme and are taken up by cells within the heart. There the particles slowly release the enzyme.

The microparticles break down into nontoxic components in the body -- an advantage over other biodegradable polymers like PLGA (polylactic-co-glycolic acid), already approved for use in sutures and grafts. When polymers such as PLGA are made into particles for drug delivery, they can induce inflammation.

Davis and his colleagues have also used the polyketal microparticles to encase anti-inflammatory drugs. This is the first report on the antioxidant enzyme-containing particles' use in a model of heart attack.

Emory and Georgia Tech scientists have also used SOD-containing particles to treat mice engineered to have a deficiency in SOD in the lung: http://www.ncbi.nlm.nih.gov/pubmed/18787098

Although the SOD particles had a protective effect when the heart was examined three days after the simulated heart attack, the beneficial effects weren't as strong three weeks later. The rats' hearts still had a 35 percent improvement compared to untreated animals, Davis says. Combining them with microparticles containing the anti-inflammatory drugs proved to provide an additional boost.

"This is likely because it is important to scavenge free radicals at early time points, but inflammation becomes more important later on," he says.

More on polyketals from Davis' lab:
http://www.nature.com/nmat/journal/v7/n11/abs/nmat2299.html
http://whsc.emory.edu/press_releases2.cfm?announcement_id_seq=16184
The Robert W. Woodruff Health Sciences Center of Emory University is an academic health science and service center focused on missions of teaching, research, health care and public service. Its components include the Emory University School of Medicine, Nell Hodgson Woodruff School of Nursing, and Rollins School of Public Health; Yerkes National Primate Research Center; Emory Winship Cancer Institute; and Emory Healthcare, the largest, most comprehensive health system in Georgia. Emory Healthcare includes: The Emory Clinic, Emory-Children's Center, Emory University Hospital, Emory University Hospital Midtown, Wesley Woods Center, and Emory University Orthopaedics & Spine Hospital. The Woodruff Health Sciences Center has $2.3 billion in operating expenses, 18,000 employees, 2,500 full-time and 1,500 affiliated faculty, 4,500 students and trainees, and a $5.7 billion economic impact on metro Atlanta.

Learn more about Emory's health sciences: http://emoryhealthblog.com - @emoryhealthsci (Twitter) - http://emoryhealthsciences.org

Jennifer Johnson | EurekAlert!
Further information:
http://www.emory.edu

More articles from Life Sciences:

nachricht New technology offers fast peptide synthesis
28.02.2017 | Massachusetts Institute of Technology

nachricht Biofuel produced by microalgae
28.02.2017 | Tokyo Institute of Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

New technology offers fast peptide synthesis

28.02.2017 | Life Sciences

WSU research advances energy savings for oil, gas industries

28.02.2017 | Power and Electrical Engineering

Who can find the fish that makes the best sound?

28.02.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>