Alzheimer’s disease causes nerve cells in the brain to die, resulting in problems with memory, speech and understanding. Little is known about how the nerve cells die, but this new research has revealed how they first lose the ability to communicate with each other, before deteriorating further.
“We've all experienced how useless a computer is without broadband. The same is true for a nerve cell (neuron) in the brain whose wiring (axons and dendrites) has been lost or damaged,” explained Dr Michael Coleman the project’s lead researcher. “Once the routes of communication are permanently down, the neuron will never again contribute to learning and memory, because these 'wires' do not re-grow in the human brain.”
But axons and dendrites are much more than inert fibre-optic wires. They are homes to the world's smallest transport tracks. Every one of our hundred billion nerve cells continuously shuttles hundreds of proteins and intracellular packages out along its axons and dendrites, and back again, during every minute of every day. Without this process, the wires cannot be maintained and the nervous system will cease to function within a few hours.
During healthy ageing this miniature transport system undergoes a steady decline, but the challenges are immense. Axons up a metre long have to survive and function for at least eight or nine decades. Over this period, our homes will need rewiring several times, but in our brains the wires are all original, surviving from childhood. In Alzheimer's disease, axons swell dramatically, ballooning to 10 or 20 times their normal diameter. These swellings disrupt transport but not, it seems, completely. Enough material gets through the swellings to keep more distant parts of the axon alive for at least several months, and probably for a year or more. This is important because it suggests a successful therapy applied during this early period may not only halt the symptoms, but allow a degree of functional recovery.
“We’ve been able to look at whole nerve cells affected by Alzheimer’s”, said Dr Michael Coleman. "For the first time we have shown that supporting parts of nerve cells are alive, and we can now learn how to intervene to recover connections. This is very important for treatment because in normal adult life, nerve cell connections constantly disappear and reform, but can only do so if the supporting parts of the cell remain. Our results suggest a time window in which damaged connections between brain cells could recover under the right conditions.”
This basic research gives hope over the longer term to the 700,000 people in the UK who live with dementia. Understanding how the brain responds to disease also tells us a lot about how it functions in all of us.
Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology
Migrating Cells: Folds in the cell membrane supply material for necessary blebs
23.11.2017 | Westfälische Wilhelms-Universität Münster
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
23.11.2017 | Information Technology
23.11.2017 | Physics and Astronomy
23.11.2017 | Life Sciences