Bioengineers 'pump' life into post-heart attack therapies

Jan 18, 2011

(PhysOrg.com) -- Bioengineers at UC San Diego are one step closer to improving therapies for heart attack victims.

A paper recently published in Biomaterials called “Hydrogels with time-dependent material properties enhance cardiomyocyte differentiation in vitro,” describes how the researchers measured the increase in stiffness that occurs in as it develops and then mimicked that change in a modified version of a biological material called hyaluronic acid. Pre-cardiac grown on these materials were found to mature into adult heart cells better than when grown on materials that did not stiffen. This process occurred despite not having the proper chemical signals around them and shows how important stiffness can be to cells.

This is why their finding is important: Stem cells are often injected into the scar tissue that results from a (called “myocardial infarction”) in a treatment called cellular cardiomyoplasty. This scar tissue is three-to-four-times stiffer than normal muscle. Since cells are normally responsive to stiffness, the stiff scar helps to block their ability to become muscle. Instead, they turn into immature bone.

“Our hypothesis for this latest effort was that we need to develop a material which we can inject that stiffens as the heart does naturally during development,” said Adam J. Engler, an assistant bioengineering professor at UC San Diego and co-author of the paper. “By placing pre-cardiac cells onto this material and allowing it to stiffen from a soft material to one that resembled normal muscle (and not the stiff scar), we can better ‘program’ the cells to become mature cardiac muscle. What we observed was that this is indeed the case.”

The bioengineers will follow this up with studies with animal experiments to see if the combination of stem cells and their material helps regenerate muscle rather than have the injected cells become immature bone as which often occurs with cellular cardiomyoplast Jennifer Young, co-author of the paper and a UC San Diego bioengineering Ph.D. student, is excited about theclinical application of her research – the potential to help improve the quality of life of patients who suffer from acute myocardial infarction (heart attack).

“It is always a very satisfying feeling to solve a challenging problem,” said Young, who chose the field of bioengineering because of its promise, cutting-edge nature and countless interesting applications. “It is rewarding to make a contribution to the field, and to see your hard work pay off. However, in a way, the most satisfying part of a breakthrough is identifying the next obstacle that needs to be overcome.”

Explore further: Molecule enhances copper's lethal punch against microbes

Related Stories

Heart derived stem cells develop into heart muscle

Apr 23, 2008

Dutch researchers at University Medical Center Utrecht and the Hubrecht Institute have succeeded in growing large numbers of stem cells from adult human hearts into new heart muscle cells. A breakthrough in stem cell research. ...

Stem cells to repair damaged heart muscle

Jun 22, 2007

In the first trial of its kind in the world, 60 patients who have recently suffered a major heart attack will be injected with selected stem cells from their own bone marrow during routine coronary bypass surgery.

Recommended for you

Breakthrough in understanding of important blood protein

11 hours ago

The human body contains a unique protein that has the unusual property of destroying itself after a few hours of existence - it must therefore be continually recreated and is no stable protein. The protein, ...

User comments : 0