Bioactive peptides provide hope for chronic wound healing
MedWire News: Two bioactive peptides known as UN3 and comb1 are able to improve the rate of chronic wound closure in mice, say US researchers who believe their findings could be developed to help treat human patients with such wounds.
"The confirmation that these peptides could act synergistically to improve human wound healing moves our research one significant step closer to clinical application. We hope that someday soon, we may be able to help transform the way in which wound care is being delivered in civilian and combat settings," said study author Ira Herman (Tufts University School of Medicine, Boston, Massachusetts) in a press statement.
"The wound-healing peptides should also prove strategic as we continue developing 'smart' devices or fully-vascularized living tissue constructs for burn patients or those patients suffering with diabetic plantar or venous stasis ulcers."
In earlier research, Herman and team demonstrated the pro-angiogenic properties of several bioactive peptides derived from endothelial cells.
Using this knowledge the researchers tested the peptide comb1, formed from a combination of tenascin X and fibrillin 1 fragments, in a mouse model of chronic wounds (cyclophosphamide triggered).
They found that application of the peptide significantly improved the rate of wound closure at 5 days, achieving a wound-healing grade (score 0-5, where 5=healed and 0=no healing) of approximately 2.8 as opposed to 1.8 in those with no peptide application.
Herman and colleagues also created another peptide - UN3 - from a combination of two naturally occurring peptides found in platelet-rich plasma (UN1 and UN2).
In vitro tests revealed that UN3 increased blood vessel wall development 1.5-fold, blood vessel growth 2.5-fold, and cell migration threefold in response to injury.
When UN3 was tested in the chronic wound mouse model, alone and in combination with comb1, it achieved a wound-healing grade of approximately 3.0 and 3.8, respectively, after 5 days.
"Despite significant progress that has been achieved in our understanding of normal wound healing process and the pathologies that lead to wound chronicity, chronic wounds of differing etiology remain a significant health care burden affecting over 5 million people annually in the United States alone," write the investigators in PLoS ONE.
"Application of the peptides markedly promotes cellular responses to injury and essentially restores wound healing dynamics to those of normal, acute wounds," they add.
"Clinical trials using the peptides will be the next step," Herman told the press.
By Helen Albert