SKINIPEDIA - Skin Encyclopedia: Unlocking Skin's Secrets P.2
Dr. Julie Segre : Unlocking Skin's Many Secrets - Part 2
In a study published in the Journal of Clinical Investigation (Connexin 26 regulates epidermal barrier and wound remodeling and promotes psoriasiform response), Segre and her colleagues recently found an important key to determining who will develop psoriasis and eczema by studying a protein called connexin 26 (Cx26). Cx26 forms communication channels that allow cells around a wound edge to tell each other to make more cells to close the wound; that tell cells in the underlying, undamaged skin layers that an emergency situation exists and ask them to make more cells; and that alert and attract immune cells to the damaged area to fight off pathogens while the wound heals. The skin produces large amounts of Cx26 when it is developing before birth, and also increases Cx26 production when tissues are damaged so they can regenerate.
Problems arise when the body does not turn off Cx26 production after a wound has healed. This puts the affected epithelial cells into an overdrive state called hyperproliferation, which stimulates the immune system. Dr. Segre hopes that finding ways to help the skin barrier heal quickly and efficiently in people with a genetic tendency to overproduce Cx26 will encourage Cx26 production to shut down in a timely manner and make it possible to minimize or eliminate psoriatic flares.
Schematic diagram of the stages of skin cell
differentiation, resulting in a barrier.
Premature babies are another group Dr. Segre and her colleagues hope they can help. They are studying how skin develops in the womb and establishes its marvelous protective barrier, and hope their new understanding will teach them how to speed up that process in premature infants, who are born before their skin is ready to keep bacteria out or body fluids in.
"Premature infants lose fluid at an alarming rate," said Dr. Segre. "If they are born before 34 weeks, so much fluid leaks out through their immature skin that they need to take in three times the amount of liquid of a baby born after 34 weeks just to keep their red blood cells, oxygen, electrolytes and nutrients circulating. We want to change that."
Learning how the skin develops will also help researchers create a synthetic barrier for thermal and chemical burn patients, whose damaged skin must be covered until new skin can regenerate. Dr. Segre said that people with severe burns have the same problems as premature infants, including difficulty maintaining body temperature, fluid loss and infection. Creating a synthetic barrier that can be put in place immediately may be crucial to surviving these acute injuries.
"Petroleum jelly just doesn't mimic skin," Dr. Segre said. "When we understand how skin truly works, we hope people will be able to design a synthetic barrier that can perform all the functions of the real one until the skin can heal itself."Intriguingly, the past, not the present, may hold the key to much of Dr. Segre's research.
"You can't look at the world today and understand why our bodies respond the way they do," Dr. Segre remarked, "because our bodies are still programmed for earlier conditions. Antibiotics were only discovered in 1928, so strong, even drastic responses to breaks in our skin are still encoded in our genome to correct what would have been a life-threatening situation in the past." Dr. Segre said that the rate of eczema in children is increasing, and may be due to the fact that our skin is programmed to coexist with dirt and farm animals, not clean suburban lawns.
"This is called the hygiene hypothesis," she explained. "It's not a fully developed story, but a number of disorders, including eczema, are becoming more common as people move into increasingly urban environments. It takes thousands, maybe millions of years to change our genome from an evolutionary standpoint. Society is evolving faster than our genome can respond."
Further read: What is Eczema is answered here and Ezcema in Depth Resources could be found here.