Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCLA scientists find male gene in brain area targeted by Parkinson’s

21.02.2006


Discovery may explain why more men than women develop the disease



UCLA scientists have discovered that a sex gene responsible for making embryos male and forming the testes is also produced by the brain region targeted by Parkinson’s disease. Published in the Feb. 21 edition of Current Biology, the new research may explain why more men than women develop the degenerative disorder, which afflicts roughly 1 million Americans.

"Men are 1.5 times more likely to develop Parkinson’s disease than women," said Dr. Eric Vilain, associate professor of human genetics at the David Geffen School of Medicine at UCLA. "Our findings may offer new clues to how the disorder affects men and women differently, and shed light on why men are more susceptible to the disease."


In 1990, British researchers identified SRY as the gene that determines gender and makes embryos male. Located on the male sex chromosome, SRY manufactures a protein that is secreted by cells in the testes.

Now, in an unexpected discovery, Vilain’s team became the first to trace the SRY protein to a region of the brain called the substantia nigra, which deteriorates in Parkinson’s disease.

Parkinson’s disease occurs when cells in the substantia nigra begin to malfunction and die. These brain cells produce a neurotransmitter called dopamine that communicates with the brain areas controlling movement and coordination.

As the cells die off, they produce less dopamine. This slows the delivery of messages from the brain to the rest of the body, leaving the person unable to initiate or control their physical movements. The condition eventually leads to paralysis.

"For the first time, we’ve discovered that the brain cells that produce dopamine depend upon a sex-specific gene to function properly," Vilain said. "We’ve also shown that SRY plays a central role not just in the male genitals, but also in regulating the brain."

Vilain’s lab used a rat model to study the effect of SRY on the brain. When the researchers lowered the level of SRY in the substantia nigra, they saw a corresponding drop in an enzyme called tyrosine hydroxylase (TH), which plays a key role in the brain’s production of dopamine.

In a surprise finding, the drop in TH occurred only in the male rats. The female rats remained unaffected.

"When we reduced SRY levels in the rats’ brains, the male animals began experiencing the movement problems caused by insufficient dopamine," Vilain said. "Low levels of SRY triggered Parkinson’s symptoms in the male rats, cutting their physical agility by half in a week.

"Initially, the rat could walk 14 steps in 10 seconds," he noted. "After we lowered the SRY levels in its brain, the rat could only manage seven steps in the same amount of time."

Vilain believes that variations in SRY levels may be linked to the onset of Parkinson’s and could offer insights into who is at risk for the disease.

"SRY may serve as a protective agent against Parkinson’s," he said. "Men who contract the disease may have lower levels of the gene in the brain."

Because SRY is found only in males, Vilain thinks women must possess another physiological mechanism that protects dopamine-producing cells in the substantia nigra.

"We suspect that estrogens in women could play the same role as SRY in protecting the female brain from Parkinson’s disease," he said. "Our lab is currently studying this hypothesis in an animal model."

Sex differences in other dopamine-linked disorders, such as schizophrenia or addiction, may also be explained by the SRY gene, Vilain said.

"It’s possible that dopamine-related disorders that reveal dramatic differences in severity and rates in the genders could depend on the SRY levels in the brain," he said.

Elaine Schmidt | EurekAlert!
Further information:
http://www.mednet.ucla.edu

More articles from Life Sciences:

nachricht Stiffness matters
22.02.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Separate brain systems cooperate during learning, study finds
22.02.2018 | 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: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Stiffness matters

22.02.2018 | Life Sciences

Magnetic field traces gas and dust swirling around supermassive black hole

22.02.2018 | Physics and Astronomy

First evidence of surprising ocean warming around Galápagos corals

22.02.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>