It is the most common form of age-related dementia, possibly the most feared disease of old age. There is no cure, and the available drugs only help to relieve symptoms without slowing progression of the disease.
One of the characteristic changes in the brains of Alzheimer's patients is the accumulation of plaques and tangles; currently, the best hope for curing or at least slowing the disease lies in developing drugs that target this buildup. Some drugs are already in clinical trials, but there is still a pressing need for more research, and for more and better drugs directed against both known and novel targets.
One of the big problems in rapidly screening potentially useful drugs has been the lack of a good model system in which Alzheimer's plaques and tangles appear quickly. However, Mike Virata and Bob Zeller, scientists working at San Diego State University, California, have come up with a new, and perhaps unlikely candidate; the humble sea squirt, Ciona intestinalis. Sea squirts are tunicates, marine organisms protected by an outer hard tunic with a soft body inside.
Adults spend their lives attached to one spot on underwater structures like the pilings of piers, sucking in water through one siphon, filtering out small plants to eat, and squirting the water back out through another siphon. However, as long ago as Darwin, it has been recognized that sea squirts may be our closest invertebrate relatives; in their immature, tadpole form, they resemble proper vertebrates, and they share about 80% of their genes with us.
Bob Zeller has been a fan of sea squirt tadpoles since starting work with them in the 1990s, when he helped develop a way of introducing foreign DNA into fertilized sea squirt eggs with almost 100% efficiency, opening the way for their use as model organisms. He and his colleague Mike Virata decided to see whether it would be possible to model Alzheimer's disease in the tiny animals, which share all the genes needed for the development of Alzheimer's plaques in humans. Incredibly, dosing the sea squirt tadpoles with a mutant protein found in human families with hereditary Alzheimer's resulted in aggressive development of plaques in the tadpoles' brains in only a day, and these, along with the accompanying behavioral defects seen in the tadpoles, could be reversed by treating with an experimental anti-plaque forming drug.
This is an important breakthrough, as all other invertebrates tested have been unable to process the plaque-forming protein, and vertebrates take months or years to make plaques. These exciting results make it a real possibility that sea squirts are an excellent model for testing new drugs in the fight against Alzheimer's disease.
Hope for Alzheimer's sufferers from an unlikely source: the sea squirt is presented in the Research Article entitled 'Ascidians: an invertebrate chordate model to study Alzheimer's disease pathogenesis', written by Michael J. Virata and Robert W. Zeller, of San Diego State University, California. The study is published in Volume 3 Issue 5/6 of the research journal, Disease Models & Mechanisms (DMM), http://dmm.biologists.org/, published by The Company of Biologists, a non-profit organisation based in Cambridge, UK.
About Disease Models & Mechanisms:
Disease Models & Mechanisms (DMM) is a new research journal, launched in 2008, that publishes primary scientific research, as well as review articles, editorials, and research highlights. The journal's mission is to provide a forum for clinicians and scientists to discuss basic science and clinical research related to human disease, disease detection and novel therapies. DMM is published by the Company of Biologists, a non-profit organization based in Cambridge, UK.
The Company also publishes the international biology research journals Development, Journal of Cell Science, and The Journal of Experimental Biology. In addition to financing these journals, the Company provides grants to scientific societies and supports other activities including travelling fellowships for junior scientists, workshops and conferences. The world's poorest nations receive free and unrestricted access to the Company's journals.
Kristy Kain | EurekAlert!
Colorectal cancer risk factors decrypted
13.07.2018 | Max-Planck-Institut für Stoffwechselforschung
Algae Have Land Genes
13.07.2018 | Julius-Maximilians-Universität Würzburg
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences