Earlier this month, we reported on work being done to improve recovery from hypertrophic scars, a type of scar that often occurs after a burn. In a similar vein, work is also underway by different researchers and institutes to develop treatment or preventative measures that are effective against other scars as well. One such group has successfully tested an enzyme-based keloid scar treatment in vitro and is currently paving the way towards the next stage of testing.
In Brief: Keloids
As mentioned in the previous article, scars form when collagen is used to fill in deeper skin injuries. Keloid scars occur when this process is taken to its extreme and an overproduction of collagen—even more so than in hypertrophic scars—ensues. Keloid scars are firm masses of scar tissue that grow beyond (sometimes well beyond) the border of the original injury. While not dangerous, keloids can be disfiguring and about 250,000 people in the U.S. need surgery every year for keloid removal. Keloids rarely come from scraped knees and elbows and usually require a burn or similar-scale skin injury to arise.
Scar formation is enabled by an enzyme called lysyl oxidase (LOX), which allows the collagen to crosslink during wound healing. Although this is needed to heal the injury, it also prevents the original architecture of the skin from getting restored and leads to scarring. The researchers decided to try a LOX-inhibiting treatment to see if this could be avoided.
And Now, Molecules
The basic idea behind what the researchers were attempting is that, by developing a small, targeted molecule, they could block LOX enough to allow the original architecture of the skin to assert itself. This was tested using what is known as the “scar-in-a-jar” model. This is an in vitro technique that cultures human tissue to create samples that overproduce collagen, like during real scar formation. For this study, the researchers cultured samples from patients with keloids as well as Dupuytren’s Contracture, a type of connective tissue condition that restricts the ability to extend the hand.
The LOX inhibitor was applied to the cultures and the samples were monitored for various biochemical and other changes. It was found that the tissue cultures showed altered collagen in a way that restored the normal skin architecture, suggesting that scar formation would be reduced or blocked. The major caveat here for anyone who is getting excited is that plenty of things that look good in a Petri dish don’t work out when applied to living systems. This is why the next stage in the research will be to perform animal tests and, if those are successful, to move on to clinical trials.
The results were presented at the 252nd National Meeting & Exposition of the American Chemical Society.
“Stopping scars before they form,” American Chemical Society web site, August 21, 2016; https://www.acs.org/content/acs/en/pressroom/newsreleases/2016/august/stopping-scars-before-they-form.html, last accessed August 21, 2016.