Injectable hydrogel shores up damaged hearts
Numerous research efforts have attempted to curb the damage caused by scar tissue that results from heart attacks. Now researchers from the University of Pennsylvania have taken yet another step forward in the development of injectable gels that can strengthen areas most weakened by heart attacks and minimize the chances of subsequent heart failure.
Every year, 750,000 people in the U.S. suffer heart attacks, which constrict the arteries of the most vital organ in our body and restrict its blood flow to a point that either damages or kills cells in its tissue. After this initial event, damage persists through the formation of scar tissue, ultimately leading to a host of other medical problems that can lead to heart failure.
Previous studies have used animal models to test the effectiveness of treating damaged areas of the heart tissue using cell injections embedded in hydrogels – networks of polymer chains filled with water that prevent the cells from leaking out of the damaged heart tissue. Interestingly, these studies revealed that even without the addition of cell injections, hydrogels alone aided in the recovery process of some animals.
Jason Burdick, lead author of the current study, along with co-authors Christopher Rodell and Robert Gorman, are examining the potential of hydrogels as a non-invasive treatment for damaged heart tissue, and taking things a step further by attempting to pinpoint specific properties of these gels that make them most effective for treating heart attack patients.
"It's important we all keep moving forward to figure out how this therapy could be used, because it's different than any current treatment," says Burdick.
Using hyaluronic acid (HA) – a sugar molecule that naturally occurs in the body – as the base, Burdick and his team attached adamantane and cyclodextrin groups in order to create a gel that can flow seamlessly through catheters. In addition, they added thiol and methacrylate groups to to promote the linkage of polymer chains following the injection of the gel into the heart tissue, creating a stiffer and longer lasting gel.
The researchers tested their gel on sheep and found that it curbs the formation of scar tissue, as well as preventing the enlargement of the heart and thinning of the heart's walls, three effects commonly observed in individuals that have suffered heart attacks.
The research focuses on the effectiveness of hydrogels in minimizing scar tissue formation in animals, so their benefit in humans has yet to be determined. However, Burdick and his team hope that eventually, human methods of delivery will be finalized and brought to the market with a catheter to allow for an effective and non-invasive way of preventing the damages brought on by heart attack-induced scar tissue.
The findings, which have yet to be published, were presented at the American Chemical Society's annual meeting this week.
The following video outlines the research.
Source: American Chemical Society