Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Discovery could lead to new types of Alzheimer’s drugs

12.07.2005


A ground-breaking new research approach to understanding the cellular processes of Alzheimer’s and other degenerative diseases has revealed a promising pathway to the development of new types of drugs for these diseases.



The discovery, made in the laboratory of Ratnesh Lal, research scientist in the Neuroscience Research Institute (NRI) at the University of California, Santa Barbara, is published in this week’s online issue of the Proceedings of the National Academy of Sciences (PNAS).

The research describes a new way of understanding the degeneration of brain cells in patients with Alzheimer’s, Huntington’s, and Parkinson’s diseases, as well as other degenerative diseases. Misfolded proteins in the cell membrane, and subsequent changes in the electrical properties of cells, provide the explanation for the cell degeneration. Specific three-dimensional structures of misfolded proteins are embedded in the cell membrane.


"It has long been thought that amyloid plaque, which has been studied for 30 years, was the cause of Alzheimer’s disease," said Lal. "Plaque isn’t the cause." He explained that the fibers of plaque are too large to directly affect small cells.

The answers may come from small globs of misshapen, misfolded proteins that make well-defined holes in cell membranes and disrupt their electrical activity, according to the study.

Amyloid protein is a sticky, globular substance created when normal cellular proteins become twisted and contorted into abnormal shapes. While amyloid formation has been associated with diseases like Alzheimer’s, Parkinson’s, and Huntington’s, scientists have puzzled over whether and how it actually kills cells and causes disease. To gain insight into this mysterious process, Lal and his research team examined the three-dimensional structure of several different proteins associated with these diseases. The researchers observed that all of the proteins folded into structures resembling ion channels, or pores within cell membranes. These pores control the electrical properties of the cell by regulating the flow of charged particles (ions) such as calcium.

When embedded into artificial membranes, the misfolded proteins were able to produce electrical currents, confirming their similarity to ion channels. Since abnormal ion balance is known to disrupt cell function and cause degeneration, these results provide proof of a possible mechanism by which amyloid formation may lead to the cellular destruction seen in these neurodegenerative diseases.

"These ion channels could serve as a model system for designing preventive and therapeutic drugs," said Lal. "You don’t need large aggregates of these amyloid proteins, the plaque, to have this disruption. Rather, small aggregates, when in contact with membrane, form ion channels and allow passage of ion current. By controlling activity and designing specific drugs to regulate these channels, we might be able to prevent and/or treat various diseases related to the amyloids."

These findings provide a major piece of the puzzle about the underlying protein misfolding associated with these degenerative diseases. Besides the diseases already mentioned, other degenerative diseases that also result from misfolded proteins include cystic fibrosis, type II diabetes, cerebrovascular dementia, arthritis, tuberculosis, as well as British and Danish famial dementias.

The researchers used atomic force microscopy (AFM) to view the ion channels. By using the AFM they were able to view these "bio-nano" molecules. The AFM allows for a look at these very small channels, which would be very difficult if not impossible to see in their native, cell-like environment with electron microscopy.

In addition to Lal, the authors of this path-breaking paper are: Arjan Quist and Ivo Doudevski of the NRI at UCSB; Han Lin of the University of Pittsburgh; Rushana Azimova and Bruce Kagan of the University of California, Los Angeles; and Douglas Ng, Blas Frangione, and Jorge Ghiso of New York University.

Gail Gallessich | EurekAlert!
Further information:
http://www.ucsb.edu

More articles from Life Sciences:

nachricht Fingerprint' technique spots frog populations at risk from pollution
27.03.2017 | Lancaster University

nachricht Parallel computation provides deeper insight into brain function
27.03.2017 | Okinawa Institute of Science and Technology (OIST) Graduate 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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>