They do not have it all figured
out, but it appears that it has become possible to manage natural scarring to
the extent of outright eliminating it.
At worst, this should produce a
treatment that will hugely reduce what scarring that we do get and may even
help reduce heart damage in heart attack victims who suffer from scarring that
lowers performance after the attack.
This should also naturally lower unnecessary
inflammation and actually speed healing in injuries also. If we can also add biologically available
oxygen while we are at it, the whole process may be hugely sped up.
So far it all seems to be quite a
simple procedure and we may just be that lucky.
Blocking a Common Sugar Molecule May Be Key to Preventing Scar
Formation
Small sugar fragments can set off a signal cascade that increases
inflammation and scar formation. A small peptide can block this process and
allow scar-free healing
By Carrie Arnold | December 12,
2010 | 4
SCARRED FOR LIFE? Rats treated with a small protein, named 15-1, show
less scar formation (in center) compared to control animals because of reduced
inflammation and collagen formation. Image: Cornelia Tolg
Most people have one somewhere: a nasty scar from an old injury. It
typically causes no serious harm, but can be unsightly. Scar-reducing creams
and other dermatological procedures can help, but no one has known how to
prevent scarring in the first place. Now scientists have discovered that the
key to scar-free wound healing could involve blocking the action of a common
sugar.
Hyaluronan is a long, gooey sugar discovered in the 1970s. Researchers
long thought that it was just another component of the extracellular slime that
surrounds all cells. Since then, hyaluronan has been shown to be a significant
player in heart development and tumor metastasis.
Scientists also have discovered that developing fetuses and newborns
have very high levels of the sugar, compared with teens and adults. And, the
former group can recover from surgery without major scarring. This led Cornelia
Tölg and Eva Turley, both of the London
Health Sciences
Center in Ontario
As humans age, levels of intact hyaluronan drop dramatically. Fragments
of hyaluronan increase as the body breaks down the intact versions. Tölg and
colleagues found that although intact hyaluronan promotes scar-free wound
healing, the hyaluronan fragments spur the formation of excess scar tissue.
The researchers manipulated the wound repair process in rats by giving
them a small protein, called peptide 15-1. The peptide prevents the hyaluronan
fragments from binding to a receptor on skin cells. Rats with wounds treated
with the peptide had significantly less scarring than control rodents. Skin
cells on the injured rats treated with it also regenerated similar to human
embryos and newborns.
When not blocked by peptide 15-1, hyaluronan fragments bind to skin
cell receptors and set off a signaling cascade that increases inflammation at
the site of the injury. Inflammation calls more immune cells to the wound to
help fight infection, along with collagen, a fibrous protein, to help seal the
wound shut. The excess collagen and rapidity with which inflammation drives
skin cells to divide to keep bacteria out ultimately causes scarring. The
researchers presented their results December 12 at the American Society for
Cell Biology's 50th annual conference in Philadelphia
A fetus is bathed in a sterile fluid, Turley says, and therefore does
not need to close wounds to prevent infection. In the germ-filled world,
however, preventing infection is a matter of life and death. "There is a
lot 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 preventing
immune cells from infiltrating the wound. Yet treatment with this peptide did
not increase the odds of infection in the lab or noticeably slow the rate of
wound healing, Tölg says.
"It's a very significant work," says Vinata Lokeshwar, a cell
biologist at the University
of Miami Miller School
The researchers still do not understand why intact and fragmented
versions of hyaluronan have such different effects on scar formation. Tölg and
Turley think that the size differences between the two molecules might help
explain their disparate effects. "It's an odd thing to have information
encoded in size," Turley says. The large, intact hyaluronan molecules
might not be able to bind very well to the skin cell receptors used by the
hyaluronan fragments, she says.
Nevertheless, the discovery is significant—even just one treatment by
peptide 15-1 may make scarring a thing of the past, Tölg and Turley conclude.
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