Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Effects of Huntington’s disease mutation more complex than supposed

23.07.2004


Competing theories about why brain cells die in Huntington’s disease may not be competitors after all, according to a report published July 23, 2004, in the online edition of the Annals of Neurology.



Researchers report finding minor molecular abnormalities of the sort proposed by these different theories in cells throughout the brain and even in the skin. Yet only select groups of cells in a few movement centers of the brain are so vulnerable to these disruptions that they degenerate and die.

The results suggest that therapeutic strategies for Huntington’s--as well as other neurodegenerative diseases such as Alzheimer’s and Parkinson’s--may have to be more complex than previously supposed.


Huntington’s is an inherited, degenerative brain disease marked by movement abnormalities--involuntary, dance-like movements called "chorea" early in the illness and later a gradual loss of the ability to move muscles voluntarily--as well as psychiatric symptoms such as depression and mood swings.

Huntington’s disease is caused by mutations in a single gene. The mutation leads to an abnormal form of the protein called huntingtin, which accumulates into toxic deposits inside nerve cells. Researchers have focused their efforts on understanding why mutant huntingtin accumulates and how it might damage brain cells.

One prominent theory notes that there is a breakdown in the clearance of abnormal proteins in Huntington’s disease. Normally, a cellular "garbage" service called the ubiquitin-proteasome system (UPS) tags defective proteins and disassembles them. In Huntington’s disease, the UPS does not appear to be fully functional, leaving defective proteins like huntingtin to accumulate.

However, researchers have also found other critical defects in the brain cells of Huntington’s patients, including a scarcity of molecules called neurotrophins that nourish brain cells, and problems with mitochondria, the "power plants" that produce energy for cells.

In their study, Ole Isacson, MD, and his colleagues at Harvard University and McLean Hospital explored the relationships between these different cellular processes in different cells inside and outside the brain.

Surprisingly, first author Hyemyung Seo, PhD, and colleagues found that the UPS is not working properly in the skin cells of Huntington’s disease either, yet there is no evidence that this harms the cells. Similarly, the researchers found abnormalities in neurotrophins and mitochondrial operation in many unaffected areas of the brain in Huntington’s disease.

"It appears that only a few select groups of cells in the brain fail to adapt to this combination of problems. The degeneration of these cells leads to Huntington’s disease," said Isacson.

An important implication of the study is that the mutant huntingtin protein does not just have one negative effect on brain cells, but several. This may mean that therapeutic strategies will have to take the form of combinations of drugs that address the different processes.

Mark Cookson, Ph.D, an expert on neurodegenerative disease at the National Institute on Aging in Bethesda, Maryland, believes this study will be of great interest to scientists who study diseases like Alzheimer’s and Parkinson’s, which also feature accumulations of abnormal proteins, problems in UPS "garbage collection," and the death of only certain vulnerable subgroups of cells.

"An obvious follow-up is to look at other neurodegenerative diseases. Presumably, there would be a pattern of cellular deficits parallel to, but distinct from those of Huntington’s disease," said Cookson.

David Greenberg | EurekAlert!
Further information:
http://www.interscience.wiley.com

More articles from Life Sciences:

nachricht Designer cells: artificial enzyme can activate a gene switch
22.05.2018 | Universität Basel

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Turning entanglement upside down

23.05.2018 | Physics and Astronomy

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>