Nail stem cells are the key to limb regeneration?
The path to limb regeneration may be suggested by nail stem cells
LifeSciencesToday based on NYU Langone Medical Center: Fingernails Reveal Clues To Limb RegenerationMammals have a remarkable ability to regenerate lost fingertips, including nails, nerves and even bones, and in this respect are no different from amphibians.
In humans, amputated fingertips can regenerate in as little as two months – a phenomenon that has so far remained virtually unexplored. It is also unknown why this ability is limited to the area associated with the nail.
In an article published in the journal Nature (Takeo et al., Wnt activation in nail epithelium couples nail growth to digit regeneration), scientists at NYU Langone Medical Center shed light on this phenomenon in mammals using genetically modified mice in their study. They described for the first time a chain of biochemical events unfolding as a result of amputation of a fingertip. The results they obtained may contribute to the development of future treatments for patients who have lost limbs.
"Everyone knows that nails are constantly growing, but no one knows why," says study leader Mayumi Ito, PhD, associate professor of dermatology at New York University School of Medicine (NYU School of Medicine). Little is known about the relationship between nail growth and the ability to regenerate bone and tissue under the nail. Dr. Ito and his team have found an important key to this process – a population of self–renewing stem cells in the proximal nail matrix – a part of the nail bed rich in nerve endings and blood vessels - stimulating nail growth. In addition, scientists have found that these stem cells depend on a family of proteins known as the Wnt signaling network for their ability to repair the fingertip bone. These same proteins play an important role in hair growth and tissue regeneration in general.
In mice with amputated fingertips and a blocked Wnt signaling pathway, claws and bones do not recover. Even more intriguing is the discovery of the possibility of manipulating the Wnt pathway and thereby stimulating the regeneration of bone and subcutaneous tissue. The results obtained by the researchers suggest that the Wnt signaling pathway is necessary for fingertip regeneration, and point to a potential treatment method that can help patients recover lost limbs. According to statistics, 1.7 million people who have undergone various amputations live in the United States.
The scientists plan to continue studying the molecular mechanisms controlling the interaction of the Wnt signaling pathway with nail stem cells, which determines the growth of new structures and tissues.
Portal "Eternal youth" http://vechnayamolodost.ru14.06.2013