Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

U-M scientists trigger new hair growth in mice

15.05.2003


Brief activation of signaling protein stimulates hair follicle growth phase



University of Michigan graduate student David Van Mater knew something strange was going on when he noticed stubble on the shaved skin of experimental mice in his laboratory. Instead of the tumors he had originally expected to see, the mice were growing hair.

Van Mater had stumbled on the discovery that beta-catenin (“bay-tuh-kuh-TEEN-in”), a signaling protein involved in embryonic development and several types of cancer, also triggers changes in adult mouse hair follicles that lead to the growth of new hair.


The discovery by Van Mater and U-M scientists Frank T. Kolligs, M.D., Andrzej A. Dlugosz, M.D., and Eric R., Fearon, M.D., Ph.D., will be published in the May 15 issue of Genes & Development.

“Other researchers have shown that beta-catenin and other genes in the Wnt (“wint”) pathway are important for normal development of hair follicles in embryos and after birth,” says Dlugosz, an associate professor of dermatology in the U-M Comprehensive Cancer Center. “What’s new about our study is the finding that a brief activation of beta-catenin in resting hair follicles could be enough to trigger the complex series of changes it takes to produce a normal hair.”

The original purpose of the research study was to learn how the Wnt signaling pathway and beta-catenin are connected to cancer development, according to Fearon, the Emanual N. Maisel Professor of Oncology in the U-M Cancer Center. “Beta-catenin carries signals from growth factors called Wnts to the cell’s nucleus,” Fearon says. “If beta-catenin expression in the cell isn’t adequately controlled and regulated, it changes normal patterns of gene expression. This can lead to several types of cancer, especially colon cancer.”

The study used genetically altered mice developed in the U-M Transgenic Animal Model Core. By adding a packaged set of genes called a construct to fertilized mouse eggs, U-M researchers created a new strain of transgenic mice with an inducible form of beta-catenin in their skin cells and hair follicles.

Van Mater induced beta-catenin signaling activity by applying a chemical called 4-OHT to shaved areas on the backs of the transgenic mice and matched control mice with normal beta-catenin genes. This chemical turned on the beta-catenin in the skin and follicles of the transgenic mice. The plan was to use 4-OHT to turn on beta-catenin activity in the transgenic mice until skin tumors developed, and then turn off beta-catenin activity to see if the tumors disappeared.

“But we never saw tumors -- just massive hyperplastic growth of hair follicle cells,” Van Mater says. The scientists also noticed other skin changes that suggested an exaggerated growth phase of the hair cycle. Dlugosz suggested applying 4-OHT just once, instead of every day, and to do it during the hair follicles’ resting phase or telogen.

“Hair follicles are like a mini-organ in the body,” explains Van Mater, a graduate student in the U-M Medical School’s Medical Scientist Training Program. “Unlike most organs in the adult body, hair follicles go through regular cycles of growth, regression and rest. They are able to regenerate completely during each growth phase. Previous studies had suggested that a Wnt signal might be the switch that drives resting hair follicles into the active growth phase. By treating the transgenic mice with a single application of 4-OHT, we hoped to mimic the effect of a short pulse of Wnt expression in normal mice.”

So Van Mater started over -- applying 4-OHT just once to the shaved backs of transgenic mice and normal mice during the telogen phase of the hair cycle. Fifteen days later, the transgenic mice needed another shave, but there were no signs of new hair growth on the control mice.

“Our findings suggest some potential strategies for inducing hair growth, but it is premature to think these results will lead to new approaches for treating common male-pattern baldness,” Dlugosz cautioned. “Many hair follicles in bald and balding men are greatly reduced in size, so merely reactivating hair growth would not produce a normal hair. Also, activation of beta-catenin in the body would need to be tightly regulated, since uncontrolled beta-catenin activity can lead to tumors of hair follicle cells or tumors in other sites, such as the colon, liver or ovary.”


The research was funded by the National Cancer Institute of the National Institutes of Health. Co-author Frank T. Kolligs, M.D., a U-M former post-doctoral scholar working in Fearon’s laboratory, is now at the University of Munich.

Nicole Fawcett | EurekAlert!
Further information:
http://www.med.umich.edu/1toolbar/whatsnew.htm

More articles from Life Sciences:

nachricht Ambush in a petri dish
24.11.2017 | Friedrich-Schiller-Universität Jena

nachricht Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

IceCube experiment finds Earth can block high-energy particles from nuclear reactions

24.11.2017 | Physics and Astronomy

A 'half-hearted' solution to one-sided heart failure

24.11.2017 | Health and Medicine

Heidelberg Researchers Study Unique Underwater Stalactites

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>