Bioactive peptides found to promote wound healing

Newly created bioactive peptides promote wound healing through the growth of new blood vessels and epithelial tissue, such as skin. These wound-healing peptides, synthesized by researchers at the Tufts Center for Innovations in Wound Healing Research, increased angiogenesis in vitro by 200%. The discovery, reported online in advance of print in Wound Repair and Regeneration, provides a better understanding of the mechanisms regulating wound healing and might lead to new therapies for acute and chronic wound healing.

"We identified specific bioactive peptides that are produced from collagenase treatment of extracellular matrix, which stimulate the healing process within a wound. By creating combinations of several key peptide fragments, we were able to synthesize an entirely novel class of wound-healing peptides that promote the fundamental response to injury: blood vessel formation and epithelialization," said senior author Ira Herman, PhD, a professor of molecular physiology and pharmacology at Tufts University School of Medicine; member of the cell, molecular & developmental biology, and cellular & molecular physiology program faculties at the Sackler School of Graduate Biomedical Sciences; and director, Tufts Center for Innovations in Wound Healing Research, all in Boston.

"This is the first time these peptides have been identified and synthesized, and we hope that these discoveries and new technologies will have broad implications for acute, chronic, burn, and scarless wound healing," Herman said.

The team from Tufts used a three-dimensional wound model to examine the effect of the bioactive peptides on wound healing. After three days, wounds treated with the peptides showed signs of robust repair, while controls did not.

First author Tatiana Demidova-Rice, BS, a PhD candidate in the cell, molecular and developmental biology program at the Sackler School of Graduate Biomedical Sciences at Tufts, said, "We found that collagenase enzyme derived from Clostridium histolyticum bacteria releases biologically active fragments — peptides — from extracellular mammalian proteins. These peptides stimulate proliferation of capillary endothelial cells, enhance microvascular remodeling in the 2-D model, and induce endothelial sprouting in a 3-D model of injury repair, and therefore are likely to have potential to stimulate blood vessel formation and promote healing in response to injury in animals and humans."

Angiogenesis, the formation of new blood vessels from existing vessels, is a key step in all types of wound healing from knee scrapes to venous stasis ulcers, pressure sores and diabetic foot ulcers. In order for tissues to be repaired, there must be an adequate blood supply bringing nutrients, oxygen, and signaling molecules to the site of the injury. Collageneses are enzymes that remodel extracellular matrix by cleaving one of its key components, collagen.