April 28, 2016

A pair of molecular signals controls skin and hair color in mice and humansand could be targeted by new drugs to treat skin pigment disorders like vitiligo, according to a report by scientists at NYU Langone Medical Center.

Finding ways to activate these pathways, researchers say, could lead to therapies that repigment skin cells damaged in vitiligo, a disfiguring illness marked by the loss of skin pigmentation, leaving a blotchy, white appearance. The same pathways could serve as targets for drug therapies that repigment grayed hair cells for people seeking a younger look but who are allergic to cosmetic dyes. Such therapies might even one day reinforce pigment to correct discoloration around scars.

In experiments in mice and human cells, researchers found that control of these skin and early-stage hair cells, known as melanocyte stem cells, is regulated by cell-to-cell signaling reactions. These reactions are part of the endothelin receptor type B (EdnrB) and the Wnt signaling pathways.

Previous research had shown that endothelin proteins and the EdnrB pathway help control blood vessel development, as well as some aspects of cell growth and division, the scientists say. But they believe that their new findings, to be published in the journal Cell Reports online April 28, are the first evidence tying the signaling pathways to the routine growth of cells that produce pigment (melanocytes) and provide color to skin and hair.

They say the study is the first to outline the link between EdnrB and Wnt signaling, confirming that EdnrB coordinates the rapid reproduction of melanocyte stem cells.

"Our study results show that EdnrB signaling plays a critical role in growth and regeneration of certain pigmented skin and hair cells and that this pathway is dependent on a functioning Wnt pathway," says study senior investigator and cell biologist Mayumi Ito, PhD. Ito is an associate professor in the Ronald O. Perelman Department of Dermatology at NYU Langone and a member of NYU Langone's Helen L. and Martin S. Kimmel Center for Stem Cell Biology.

Among the study's key findings, Ito reports, was that mice bred to be deficient in the EdnrB pathway experienced premature graying of their fur.

Study co-lead investigator and postdoctoral fellow Wendy Lee, PhD, says the pathway's involvement in determination of hair color was "clearly evident" in the mice when she first examined them.

In further experiments in mice, stimulating the EdnrB pathway resulted in a 15-fold increase in melanocyte stem cell pigment production within two months, producing what Ito calls "hyperpigmentation." Wounded skin in normally white mice became dark upon healing.

In the latest study, Ito and her team found that blocking Wnt signaling stalled stem cell growth and the maturing of stem cells into normally functioning melanocytes, even when endothelin proteins were present. This led to mice with unpigmented grayish coats.

Ito says her team plans further investigations into how other cell repair and signaling pathways interact with EdnrB and melanocyte stem cells.

According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, vitiligo occurs in about 1 percent of people worldwide.

Explore further: New research provides clues on why hair turns gray

A new study by researchers at NYU Langone Medical Center has shown that, for the first time, Wnt signaling, already known to control many biological processes, between hair follicles and melanocyte stem cells can dictate ...

Mammals possess the remarkable ability to regenerate a lost fingertip, including the nail, nerves and even bone. In humans, an amputated fingertip can sprout back in as little as two months, a phenomenon that has remained ...

A pathway known for its role in regulating adult stem cells has been shown to be important for hair follicle proliferation, but contrary to previous studies, is not required within hair follicle stem cells for their survival, ...

Regenerative medicine may offer ways to banish baldness that don't involve toupees. The lab of USC scientist Krzysztof Kobielak, MD, PhD has published a trio of papers in the journals Stem Cells and the Proceedings of the ...

The human body maintains a healthy layer of skin thanks to a population of stem cells that reside in the epidermis. Previously, the signals responsible for regulating these so-called 'interfollicular epidermal stem cells' ...

Nicotinamide riboside (NR) is pretty amazing. It has already been shown in several studies to be effective in boosting metabolism. And now a team of researchers at EPFL's Laboratory of Integrated Systems Physiology (LISP), ...

Everything you eat or drink affects your intestinal bacteria, and is likely to have an impact on your health. That is the finding of a large-scale study led by RUG/UMCG geneticist Cisca Wijmenga into the effect of food and ...

In a major breakthrough, scientists at the Gladstone Institutes transformed skin cells into heart cells and brain cells using a combination of chemicals. All previous work on cellular reprogramming required adding external ...

For the first time, scientists studying stool transplants have been able to track which strains of bacteria from a donor take hold in a patient's gut after a transplant. The team, led by EMBL with collaborators at Wageningen ...

Researchers at the Icahn School of Medicine at Mount Sinai say that tiny doses of a cancer drug may stop the raging, uncontrollable immune response to infection that leads to sepsis and kills up to 500,000 people a year in ...

Age-related changes in the human pancreas govern how our bodies respond to rising and falling blood sugar levels throughout our lifetimes, and could affect whether we develop diabetes as adults. But it's been nearly impossible ...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Read more from the original source:
Stem cell study finds mechanism that controls skin and ...

Comments are closed.