Navigation Links
Discovery Sheds Light on Huntington's Disease
Date:6/4/2009

Researchers identify protein that could lead to treatment or prevention

THURSDAY, June 4 (HealthDay News) -- Scientists have pinpointed a protein that plays a key role in cell death in Huntingdon's disease, a degenerative disorder that leads to uncontrolled movements and loss of intellectual functioning.

The discovery raises hope that drugs could be developed to slow or halt the disease, according to a study in the June 5 issue of Science.

In Huntington's disease, cells in the corpus striatum, the area of the brain that controls movement, gradually die off.

Previous research has shown that people with Huntington's have a genetic defect that produces a mutant version of the protein "huntingtin," which accumulates in cells throughout the body.

But for reasons scientists didn't understand, the protein only kills cells in the corpus striatum. The protein causes little damage to tissues elsewhere.

In the new study, researchers discovered that a tiny protein called "rhes" -- found only in the corpus striatum -- interacts with the mutant huntingtin proteins, causing cell death.

The findings explain the pattern of brain damage in Huntington's disease and suggest strategies for developing new drug therapies, researchers at Johns Hopkins University said.

"It's always been a mystery why, if the protein made by the HD (Huntington's disease) gene is seen in all cells of the body, only the brain, and only a particular part of the brain, the corpus striatum, deteriorates," said Dr. Solomon H. Snyder, a professor of neuroscience at Johns Hopkins. "By finding the basic culprit, the potential is there to develop drugs that target it and either prevent symptoms or slow them down."

Huntington's is a familial disease, passed from parent to child through a gene mutation. A child of someone with Huntington's has a 50-50 chance of inheriting the gene, according to the National Institute of Neurological Disorders and Stroke.

Because the damage from the faulty gene is limited to the corpus striatum, researchers went searching for proteins that interacted specifically and exclusively with the huntingtin protein in that part of the brain.

Rhes is found almost exclusively in the corpus striatum, according to the study.

Using human and mouse cells, researchers found that rhes interacted with both healthy and mutant versions of huntingtin protein, but that it bound much more strongly to mutant huntingtin, also known as mHtt.

"Touching or binding is one matter, but death is altogether another," Snyder said.

Further tests using human embryonic cells and brain cells taken from mice showed that when both mHtt and rhes were present in the same cells, half the cells died within 48 hours. Rhes or mHtt alone did not cause cell death.

"Here's the rhes protein, we've known about it for years, nobody ever really knew what it did in the brain or anywhere else," Snyder said. "And it turns out it looks like the key to Huntington's disease."

Researchers also did a set of tests to learn more about the role of rhes. Previous research has shown that the abnormal huntingtin proteins form clumps in cells throughout the body and brain, but that there are fewer of the clumps in the corpus striatum.

"This has led to much controversy: Are the clumps toxic, or is it the lack of clumps that's toxic to these brain cells?" said Srinivasa Subramaniam, a postdoctoral fellow at Johns Hopkins.

Experiments showed that adding rhes to cells with abnormal huntingtin led to fewer clumps, but the cells died.

Researchers said that the unclumping of mutant huntingtin proteins by rhes might cause the cell death.

"Since rhes is highly found in the corpus striatum, clumping somehow protects cells in other tissues of the body from dying," Subramaniam said.

The team is currently testing to see if removing rhes from mice with Huntington's disease can slow or stop brain cells from dying.

"Now that we've uncovered the role of rhes, it's possible that drugs can be designed that specifically target rhes to treat or even prevent the disease," Snyder said.

More information

The National Institute of Neurological Disorders and Stroke.



-- Jennifer Thomas



SOURCE: Johns Hopkins University, news release, June 4, 2009


'/>"/>
Copyright©2009 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Discovery of sugar sensor in intestine could benefit diabetes
2. Discovery suggests location of genes for breast density, a strong risk factor for breast cancer
3. Stem cell research produces a key discovery for Fragile X Syndrome
4. Welch Foundation gives $1.6 million for drug discovery research
5. New discovery leaves blood-doping athletes scratching their heads
6. Chemical Diversity Initiates International Prostrate Cancer Discovery Partnership
7. New discovery leaves blood-doping athletes scratching their heads
8. Discovery of widespread tumor growth gene holds promise for effective anti-cancer treatment
9. Discovery supports theory of Alzheimers disease as form of diabetes
10. Discovery Health CME Explores the Benefits and Risks of Aspirin in Aspirin Therapy: Maximizing the Benefits
11. New discovery may improve treatment of one of the worlds leading causes of blindness
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Discovery Sheds Light on Huntington's Disease 
(Date:10/13/2017)... ... ... The American Board of Family Medicine's (ABFM) Board of Directors has selected Warren ... James C. Puffer upon his retirement. Dr. Newton will serve in the position of ... end of 2018. Upon assuming the role of President and CEO on January 1, ...
(Date:10/13/2017)... ... ... PurhealthRX , a leading Health and Nutrition Company, is announcing the ... spectrum CBD oil will revolutionize the rapidly growing CBD market by reducing the amount ... into liquid products, while reducing costs to end users. , The team of researchers ...
(Date:10/13/2017)... (PRWEB) , ... October 13, 2017 , ... Lori R. ... a member of ElderCounsel, a national organization of elder law and special needs planning ... laws and rules. It also provides a forum to network with elder law attorneys ...
(Date:10/13/2017)... SAN LUIS OBISPO, Calif. (PRWEB) , ... October 13, 2017 , ... ... with Alzheimer’s or dementia. However, many long-term care insurance companies have a waiver for ... mean is the 90-day elimination period, when the family pays for care, is often ...
(Date:10/13/2017)... ... October 13, 2017 , ... Ellevate Network, the leading ... to advocate for action towards gender equality at their inaugural Summit in New York ... globe, and reached a social audience of over 3 million. To watch the Mobilize ...
Breaking Medicine News(10 mins):
(Date:10/11/2017)... , Oct. 11, 2017  Caris Life Sciences ... on fulfilling the promise of precision medicine, today announced ... joined Caris, Precision Oncology Alliance™ (POA) as its 17 ... centers, the St. Jude Crosson Cancer Institute will help ... the use of tumor profiling, making cancer treatment more ...
(Date:10/7/2017)... --  Provista, a proven leader in the supply ... power, today announced a new resource area on Provistaco.com ... is the online home for case studies, articles on ... releases, slideshows and events. ... at their fingertips, viewers can also watch short videos ...
(Date:10/2/2017)... Mich. , Oct. 2, 2017 Diplomat ... 8th Day Software and Consulting, LLC , and ... 8th Day Software, based in Tennessee ... LLC. 8th Day expands EnvoyHealth,s service offerings for health ... development. "In an ...
Breaking Medicine Technology: