When Michael Harrison, a paediatric surgeon at the University of California, San Francisco, began to perform the first ever surgeries on fetuses, he noticed something curious about the babies who survived. Incisions he had made in them in the womb seemed to heal without scarring. Part of Nature Outlook: Skin. Harrison asked Michael Longaker, a postdoctoral researcher in his laboratory, to investigate the phenomenon. Longaker was sceptical. Longaker, now a plastic surgeon with a focus on regenerative medicine at Stanford University in California, has not yet unravelled the mystery completely.
Nor have other researchers. Although many studies have provided valuable insight into how scarring occurs, they have yielded few clinically useful treatments. Yet many researchers are cautiously optimistic that a better understanding of the mechanisms that lead to scarring will pave the way for innovative strategies for reducing the formation of scar tissue. The field of skin regeneration is moving in a different direction, Badylak says.
Rather than growing skin in Petri dishes in the lab, and then transplanting it onto people, researchers are using the body as a bioreactor and encouraging skin to do what it did during fetal development — regenerate. They want to find out more about how scarring occurs, as well as how it might be stopped. Cut the skin and it will bleed.
And then it will heal. Initially, a clot forms to staunch blood flow, which kicks off a massive inflammatory response. Next, the wound begins to fill. Spindle-shaped cells known as fibroblasts migrate to the damaged area and churn out collagen and other proteins that provide tissue with structure.
Within three weeks of the injury occurring, the wound has healed. But such speedy healing has a major downside. These quick repairs often result in scars, particularly when the wound is deep. In healthy skin, collagen fibres form a lattice. But during wound healing, fibroblasts lay down collagen fibres parallel to each other, which creates tissue that is stiff and weak. But large scars can be life-changing. That can be especially problematic when scars cover joints.
Imagine, Gibson says, not being able to hold a fork or to raise your arms to wash your hair. But scarring might not be inevitable. Fetal skin begins to scar only late in gestation, which suggests that human skin possesses at least some regenerative capabilities. All researchers have to do is to work out how to unlock them. Fetal wounds are not the only wounds that are resistant to scarring. Thomas Leung, a dermatologist at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia, noticed that older people often develop thinner scars than do younger adults.
To understand why, Leung turned to mice. In one-month-old animals, such wounds healed with a thick scar and never closed fully — similar to earring holes in people, Leung says. In month-old mice, which are roughly equivalent to year-old people, healing took longer, but the holes closed completely, and with less scarring. The same observations held for wounds on the backs of the mice. Fluorescence micrograph of human skin fibroblasts.
Leung and his colleagues wondered whether a component of the blood of young mice promotes scar formation. To test the idea, they joined together old and young mice, giving them a shared circulatory system through a surgical technique called parabiosis. The team found that exposure to the blood of young animals caused wounds in elderly mice to scar 1. Further experiments revealed the probable culprit: Cxcl12 , a gene that encodes a protein called stromal cell-derived factor 1 SDF1.
If you want to make a scar look less noticeable, you may want to try a natural remedy. There are many people who believe that natural remedies can get the job done.
As with any home remedy, have a conversation with your doctor before starting. Your doctor can offer insights and recommendations about which remedies you should or should not try. Read this article in Spanish. Whether your pockmarks were caused by acne, chickenpox, or another skin condition, the resulting scar can be difficult to fade.
Here's what works. Depending on appearance, some people may want to get rid of the keloids they have. We'll share some tips for fading chicken pox scars, including natural products, over-the-counter options, and professional treatments.
Here are 16 of the best sunscreens on the market in spray, lotion, and solid forms, and for different needs. They're tried and true. Everyone can benefit from a good facial cleanser, and many products are specially formulated for dry, sensitive skin. Blue lips are most often caused when something is preventing you from getting enough oxygen into your body.
In time, some collagen breaks down at the site of the wound and the blood supply reduces. The scar gradually becomes smoother and softer. Although scars are permanent, they can fade over a period of up to 2 years. It's unlikely they'll fade any more after this time.
Stretch marks are narrow streaks or lines that appear on the skin's surface when the deeper layer of skin dermis tears. They're often caused by hormonal changes during pregnancy or puberty , or as a result of bodybuilding or hormone replacement therapy.
Page last reviewed: 23 October Next review due: 23 October Overview - Scars Contents Overview Treatment. A scar is a mark left on the skin after a wound or injury has healed. Types of scars A scar can be a fine line or a pitted hole on the skin, or an abnormal overgrowth of tissue. Normal fine-line scars A minor wound like a cut will usually heal to leave a raised line, which will gradually fade and flatten over time.
Keloid scars A keloid scar is an overgrowth of tissue that happens when too much collagen is produced at the site of a wound. Silicone sheets can be washed and re-used. Silicone gel dries as a very thin layer and will stay on curved skin surfaces that move throughout the day. Silicone therapy is best used hours a day for months. Massage, vibration and rubbing the scars with various textures can help overly sensitive scars.
These occur when the nerves in the skin and deeper tissues are affected by the injury or surgery. The scar may also be submerged in slightly abrasive particles. The goal of this is to reduce scar sensitivity and to help the skin and nerves become tolerant of the normal forces of everyday living. It can be started as soon as the skin and repaired tissues have healed.
Injections or surgery can be effective for special scar problems. Burn scars or other more serious injuries can require aggressive treatment. Special gloves or topical treatment may be used for burn scars.
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