Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Tiny but toxic: MBL researchers discover a mechanism of neurodegeneration in Alzheimer's disease

Tiny, toxic protein particles severely disrupt neurotransmission and inhibit delivery of key proteins in Alzheimer's disease, two separate studies by Marine Biological Laboratory (MBL) researchers have found.

The particles are minute clumps of amyloid beta, which has long been known to accumulate and form plaques in the brain of Alzheimer's patients.

"These small particles that haven't aggregated into plaques—these are increasingly being seen as the really toxic species of amyloid beta," says Scott Brady of University of Illinois College of Medicine, who has been an MBL investigator since 1982.

Brady and his colleagues found that these particles inhibit neurons from communicating with each other and with other target cells in the body.

"The disease symptoms for Alzheimer's are associated not with the death of the neurons – that is a very late event – but with the loss of functional connections. It's when the neuron is no longer talking to its targets that you start to get the memory deficits and dementia associated with the disease," Brady says.

The amyloid beta particles activate an enzyme, CK2, which in turn disrupts the "fast axonal transport" system inside the neuron, Brady found. This transport system has motor proteins that move various kinds of cargo (including neurotransmitters and the associated protein machinery for their release) from place to place in the neuron on microtubule tracks.

Brady's findings are complemented by a new study by Rudolfo Llinás of New York University School of Medicine. Brady and Llinás both conduct neuroscience research at the MBL using the giant nerve cell of the Woods Hole squid, Loligo paeleii, as a model system.

Llinás found that activation of CK2 blocks neurotransmission at the synapse – the point where the neuron connects to its target.

"Disruptions in the fast axonal transport system are probably key elements in the pathogenesis of Alzheimer's and other adult-onset neurodegenerative diseases, such as Parkinson's and ALS," says Brady. "It doesn't mean that is the only thing going on, or that it is the triggering feature of the disease. But we do know that changes in the fast axonal transport system are sufficient to cause the 'dying back' of neurons that is characteristic of these diseases."

The new findings suggest the possibility of designing a drug to inhibit CK2 activation in Alzheimer's patients. However, a prior study by Brady found that activation of another enzyme, GSK3, in Alzheimer's also disrupts the fast axonal transport system. It may therefore be necessary to inhibit both enzymes.

"There haven't yet been any therapies designed for Alzheimer's with the idea of protecting the fast axonal transport system," says Brady. "But if there were, they would have to inhibit the activation of both CK2 and GSK3. We can't think of it as a single thing going wrong. There are several things going wrong."


Pigino, G., et al. (2009) Disruption of fast axonal transport is a pathogenic mechanism for intraneuronal amyloid beta. PNAS: doi 10.1073/pnas0901229106.

Moreno, H. et al. (2009) Synaptic transmission block by presynaptic injection of oligomeric amyloid beta. PNAS: doi 10.1073/pnas09000944106.

Background information:

Lapointe, N.E., et al. (2009) The amino terminus of tau inhibits kinesin-dependent axonal transport: Implications for filament toxicity. J. Neurosci. Res. 87(2): 440-451.

The MBL is a leading international, independent, nonprofit institution dedicated to discovery and to improving the human condition through creative research and education in the biological, biomedical and environmental sciences. Founded in 1888 as the Marine Biological Laboratory, the MBL is the oldest private marine laboratory in the Western Hemisphere.

Diana Kenney | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>