Novel Gel Boosts Blood Flow in Patients with Arterial Disease

An injectable gel derived from the natural scaffolding in human muscle holds promise for treating arterial disease, say engineers at the University of California, San Diego.

Kristopher Sturgis

A new treatment could be used to treat poor blood circulation caused by advanced peripheral artery disease, a condition that can lead to infection and limb amputation.

The idea derives from a similar approach to repairing heart muscle used on pigs, says Karen Christman, professor of bioengineering at UC San Diego and senior author of the paper describing the work.

"We had initially developed a similar material that showed significant promise for repairing the heart after a heart attack," Christman said. "This previous material was derived from the natural scaffolding, or extracellular matrix, of pig hearts. We therefore developed this new material derived from the extracellular matrix of skeletal muscle to treat the damaged muscle in peripheral artery disease patients."

Christman and her team recently tested the injection therapy procedure on rats suffering from the disease and found that the use of natural scaffolding from muscle tissue improved the blood flow and promoted muscle remodeling.

"We injected a gel that sets up into a porous and fibrous material in the damaged tissue," Christman says. "It then provides a new scaffold and appropriate cues for the body's cells to migrate into and help repair the damaged region, improving the blood vessel network, and helping to regenerate muscle tissue."

In their study, Christman found that the hydrogel actually increased the diameter of the rats' arterioles, which promptly led to improved blood flow to the limbs. Study results showed that in just 35 days, the animals treated with the injection therapy had restored healthy muscle tissue comparable to rats unaffected by arterial disease. The promising results could make the injection treatment a possible solution to a disease that doesn't offer many treatment options.

"Most people have looked at cell or growth factor therapies," Christman said. "To date, injectable biomaterials have mainly been examined for delivering these cell or growth factor therapies. To our knowledge, no one has developed an injectable material scaffold to treat both the low blood flow and muscle damage associated with peripheral artery disease."

Approximately 10 million Americans suffer from PAD, according to the National Center for Biotechnology Information. The condition can lead to a bevy complications including tissue damage decreased blood flow, and tissue necrosis --  and as these symptoms escalate, they can result in limb amputation and even death. Restoring natural blood flow for these patients is critical, however, practical therapy solutions have been difficult to come by, and as a result, amputation is required in many severe cases.

In the future, Christman hopes to continue to adapt the method to explore other disease models to see where this kind of injection therapy can have a similar impact. The group also plans to refine the safety protocols so that this treatment option can be produced on a larger scale to treat as many patients as possible.

With over 200,000 amputations performed a year in North America and Europe alone due to poor circulation and arterial disease complications, Christman believes this kind of therapy could be a promising solution for countless patients worldwide.

"If successful, this could improve blood flow in critical limb ischemia patients -- the most severe and advanced form of peripheral artery disease -- to prevent amputations and other complications, while being significantly less expensive than cell therapies."

Kristopher Sturgis is a contributor to Qmed and MPMN.

Like what you're reading? Subscribe to our daily e-newsletter.