They do not have it all figuredout, but it appears that it has become possible to manage natural scarring tothe extent of outright eliminating it.
At worst, this should produce atreatment that will hugely reduce what scarring that we do get and may evenhelp reduce heart damage in heart attack victims who suffer from scarring thatlowers performance after the attack.
This should also naturally lower unnecessaryinflammation and actually speed healing in injuries also. If we can also add biologically availableoxygen while we are at it, the whole process may be hugely sped up.
So far it all seems to be quite asimple procedure and we may just be that lucky.
Blocking a Common Sugar Molecule May Be Key to Preventing ScarFormation
Small sugar fragments can set off a signal cascade that increasesinflammation and scar formation. A small peptide can block this process andallow scar-free healing
By Carrie Arnold | December 12,2010 | 4
SCARRED FOR LIFE? Rats treated with a small protein, named 15-1, showless scar formation (in center) compared to control animals because of reducedinflammation and collagen formation. Image: Cornelia Tolg
Most people have one somewhere: a nasty scar from an old injury. Ittypically causes no serious harm, but can be unsightly. Scar-reducing creamsand other dermatological procedures can help, but no one has known how toprevent scarring in the first place. Now scientists have discovered that thekey to scar-free wound healing could involve blocking the action of a commonsugar.
Hyaluronan is a long, gooey sugar discovered in the 1970s. Researcherslong thought that it was just another component of the extracellular slime thatsurrounds all cells. Since then, hyaluronan has been shown to be a significantplayer in heart development and tumor metastasis.
Scientists also have discovered that developing fetuses and newbornshave very high levels of the sugar, compared with teens and adults. And, theformer group can recover from surgery without major scarring. This led CorneliaTölg and Eva Turley, both of the London Health Sciences Center in Ontario
As humans age, levels of intact hyaluronan drop dramatically. Fragmentsof hyaluronan increase as the body breaks down the intact versions. Tölg andcolleagues found that although intact hyaluronan promotes scar-free woundhealing, the hyaluronan fragments spur the formation of excess scar tissue.
The researchers manipulated the wound repair process in rats by givingthem a small protein, called peptide 15-1. The peptide prevents the hyaluronanfragments from binding to a receptor on skin cells. Rats with wounds treatedwith the peptide had significantly less scarring than control rodents. Skincells on the injured rats treated with it also regenerated similar to humanembryos and newborns.
When not blocked by peptide 15-1, hyaluronan fragments bind to skincell receptors and set off a signaling cascade that increases inflammation atthe site of the injury. Inflammation calls more immune cells to the wound tohelp fight infection, along with collagen, a fibrous protein, to help seal thewound shut. The excess collagen and rapidity with which inflammation drivesskin cells to divide to keep bacteria out ultimately causes scarring. Theresearchers presented their results December 12 at the American Society forCell Biology's 50th annual conference in Philadelphia
A fetus is bathed in a sterile fluid, Turley says, and therefore doesnot need to close wounds to prevent infection. In the germ-filled world,however, preventing infection is a matter of life and death. "There is alot of evolutionary pressure to heal wounds really quickly," she says."We heal at the expense of tissue architecture."
Peptide 15-1 seems to block the inflammatory processes by preventingimmune cells from infiltrating the wound. Yet treatment with this peptide didnot increase the odds of infection in the lab or noticeably slow the rate ofwound healing, Tölg says.
"It's a very significant work," says Vinata Lokeshwar, a cellbiologist at the University of Miami Miller School
The researchers still do not understand why intact and fragmentedversions of hyaluronan have such different effects on scar formation. Tölg andTurley think that the size differences between the two molecules might helpexplain their disparate effects. "It's an odd thing to have informationencoded in size," Turley says. The large, intact hyaluronan moleculesmight not be able to bind very well to the skin cell receptors used by thehyaluronan fragments, she says.
Nevertheless, the discovery is significant—even just one treatment bypeptide 15-1 may make scarring a thing of the past, Tölg and Turley conclude.
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