After an injury or surgical procedure, scars often linger as a visual reminder of the trauma the body has endured. Cosmetically, they may be unsightly. And, as wounds heal, scars can cause tissue to contract, limiting mobility, inducing pain and causing functional problems later on.
“It's an astronomical burden on our healthcare system,” says plastic surgeon Steven Moran, chair of the Division of Plastic Surgery and Reconstructive Surgery at the Mayo Clinic’s Center for Reconstructive Transplant Surgery.
For centuries, people have attempted to find cures for unseemly or uncomfortable scarring. These treatments, which range from surgical removal to freezing scars with liquid nitrogen, often deliver inconsistent results.
But what if, in lieu of a silver bullet to treat existing scars, medical providers could prevent them from forming in the first place? In two recent studies, researchers have discovered novel ways to do just that. Like something straight from science fiction, topical or injected medicines may allow tissue to grow back, complete with hair follicles, sweat glands, skin oil and pores.
Types of Scarring
Scars can form in many ways throughout the body. When the dermis — the second layer of skin — is damaged, the tissue commonly heals improperly. Scars can also form when muscle is stitched together during surgery, or when a ligament or tendon is torn.
In healthy tissue, cells are arranged in a very organized fashion. But when tissue is damaged, cells and other substances, like collagen, rush to fill in the wound. In this process, the body may send too much collagen or new cells may be disorganized. Collagen, which is found throughout the body, is key to the healing process. But when there is too much in a small space, as is the case with many scars, there may be visible differences in the skin, like raised or reddened tissue.
An excess of collagen and other proteins can form hypertrophic scars. These often appear reddish, elevated and hard, compared with the surrounding tissue. In some cases, collagen and other extracellular substances can travel outside the bounds of the original wound, causing bumps or nodules in the skin called keloids. These may surface months or years after the original trauma and can cause itching and discomfort. A person’s likelihood of developing severe scars, and especially keloids, can depend on genetics, ethnicity and how well the wound was treated.
Current Treatment Methods
Scientists have long devised ways to disappear scars. Dermatologists or plastic surgeons may start by applying tape to relieve tension on tissue around the wound and lessen the chances of developing a hypertrophic scar, says Ailynne Marie Vergara-Wijangc, owner of VW Dermatology in the Philippines.
Silicone gels, sheets and other products can prevent hypertrophic scars by keeping wounds hydrated and can help heal existing ones. For keloid and other scars, some medical providers inject cortisone or other steroids to reduce the thickness.
Other treatment methods include freezing the scar, laser therapy, onion extract and even radiation therapy. In a review of scar treatment methods published in the journal Facial Plastic Surgery, researchers found that many of the existing while some of the current treatments may be effective, results are often inconsistent. For instance, the authors state the chances of a scar returning after surgical removal — one of the most established and effective methods — is up to 80%.
“People have tried everything, and we have not been able to convince or trick the cells into healing normally in a non-irritated way,” Moran says. One of the best ways to minimize the effects of a scar, he says, is preventative — keep the wound clean and moist, avoid repetitive trauma and protect it with sunscreen.
But if scientists can create an easy-to-use, viable method for getting wounds to heal completely, rather than scar over, the need for such treatments could become null. “It's kind of been the Holy Grail,” Moran says.
The Future of Tissue Repair?
This week, Moran's team at the Mayo clinic published a preclinical study indicating that an off-the-shelf product can be applied topically to heal ischemic wounds — those that arise when arteries are clogged, preventing blood from reaching the skin.
Another paper, published last week in Science by a team of Stanford researchers, indicates that injecting a drug into the edge of a skin wound could prevent keloid and hypertrophic scars from forming. In the animal study, scientists were able to block a key chemical pathway in the cells, allowing them grow just like normal skin.
In both cases, scientists were able to induce the regeneration of cells complete with all the typical organelles. With these key cellular components, Moran says it’s more likely that the body will promote regenerated cell growth, rather than scarring. Plus, the body naturally produced skin cells, sebaceous glands and hair follicles. With these components, previous wounds can operate like healthy tissue, with similar levels of stretchiness and hydration.
“The first thing we were shocked by was all the hair in the healed wound,” plastic surgeon Michael Longaker, senior author on the study and professor of medicine at Stanford, said in a prepared statement. “We were also able to see normal glands and showed that the skin was just as strong as unwounded skin.”
For now, neither research group has gone through clinical trials to test how these methods work in humans. But Moran says he feels determined to make regenerative medicines available as quickly and safely as possible. “I have patients who need this every day,” he says. “There’s such a huge need for it and I'm glad so many people are working on it.”