Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protein that controls hair growth also keeps stem cells slumbering

28.01.2008
A drug's unsightly side effect leads to a new understanding of how stem cells maintain their potency

Like fine china and crystal, which tend to be used sparingly, stem cells divide infrequently. It was thought they did so to protect themselves from unnecessary wear and tear. But now new research from Rockefeller University has unveiled the protein that puts the brakes on stem cell division and shows that stem cells may not need such guarded protection to maintain their potency.

This research, to be published in the January 25 issue of Cell, raises questions about what stem cells need in order to maintain their ability to regenerate tissue. It may also be key in developing new treatments for thinning hair.

The impetus for the work began five years ago when Elaine Fuchs, head of the Laboratory of Mammalian Cell Biology and Development, and several researchers in her lab discovered that the protein NFATc1 was one of only a few that are highly expressed within the stem cell compartment of the hair follicle. Clinical research, meanwhile, showed that a particular immunosuppressant that inhibits NFATc1, a drug called cyclosporine A, has a rather unsightly side effect: excessive hair growth.

... more about:
»Horsley »NFATc1 »Stem »cyclosporine »stem cells

Fuchs and Valerie Horsley, a postdoc in her lab, realized that there was a connection between the drug's side effect and the abundance of NFATc1 within the hair follicle's stem cell compartment -- the bulge. The mice they treated with the drug grew fur at a much faster rate than mice they did not treat. The researchers then showed that this excessive hair growth was due to increased stem cell activity within the bulge, a process that cranked up the production of hair. Specifically, the hair cycle shifted gears from its resting phase, when stem cells slumber, to its growth phase, when stem cells proliferate.

To maintain their multipotent properties, though, it appears that these stem cells hardly needed much "rest" at all. These findings came as a surprise to the researchers, who, like their colleagues, had believed that stem cells proliferating infrequently protected them from depletion or mutations that would lead to hair loss. "It seems like the resting phase isn't as necessary as was once thought," says Horsley. "Even though these stem cells are highly proliferative, they still maintain their stem cell character."

Using genetically engineered mice bred by colleagues at Harvard Medical School, Horsley and Fuchs then further explored what happens when skin stem cells lack NFATc1. They found that these mice looked exactly like the hairy mice that were treated with cyclosporine A: The loss of NFATc1 didn't stop the hair cycle, but rather shortened the resting phase and prompted precocious entry to the growth state.

In probing the underlying mechanisms mediating this process, Horsley and Fuchs discovered that NFATc1, a transcription factor, blocks the expression of a gene that provides the cell cycle with "go ahead" signals at certain checkpoints. By blocking these signals, NFATc1 prevents the stem cells from dividing, preventing unnecessary wear and tear. These same cells, if treated with cyclosporine A, show a rapid loss of the transcription factor, an effect that turns the light green at these checkpoints.

For those with thinning hair, this research may hold promise. As people age, the resting phase of the hair cycle gets longer and longer such that the stem cells proliferate less frequently and hair does not grow at the rate it once did. "If we could use a local and more specific inhibitor of NFATc1 than cyclosporine A to stimulate these stem cells, which are just sitting there during an extended resting phase, we might be able to promote new hair growth," says Fuchs, who is Rebecca C. Lancefield Professor at Rockefeller and an investigator at the Howard Hughes Medical Institute. "In a sense, by blocking NFATc1 activity in our older mice, their hair follicles were brought back to what appeared to be a more youthful state."

So far, these proliferating stem cells lacking NFATc1 have not led to increased tumor formation, which is often a dangerous byproduct of triggering stem cells into action. "This is the first case where we have been able to activate the hair cycle without accompanying signs of tumorigenesis," says Fuchs. "If we can control the activation process of follicle stem cells without promoting tumorigenesis, then this would be a big move in the right direction."

Thania Benios | EurekAlert!
Further information:
http://www.rockefeller.edu

Further reports about: Horsley NFATc1 Stem cyclosporine stem cells

More articles from Life Sciences:

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Millions through license revenues

27.04.2017 | Health and Medicine

The TU Ilmenau develops tomorrow’s chip technology today

27.04.2017 | Information Technology

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>