Researchers have developed an effective new method of testing cognitive decline in mice with the disease, using an automated touch screen. It is hoped the screen will also allow researchers to study more effectively the cognitive difficulties in other neurodegenerative disorders such as in Alzheimer's and CJD.
Huntington's disease is a genetic disease affecting around 8 in 100,000 people. It is characterised by a progressive decline in cognitive functioning (including memory loss, intellectual decline and disorientation) together with the appearance of abnormal movements and impaired motor skills (such as unsteady gait and poor coordination).
There is currently no cure and whilst some symptoms can be alleviated, no treatments have been developed that help with cognitive deficits, a distressing aspect of the disease.
Whilst useful mouse models mimicking this disorder have been developed, it has been difficult to test cognitive skills such as learning, because most traditional experiments demand a level of physical performance that the mice cannot deliver due to the effect of the disease on their motor abilities.
The automated screen developed by Cambridge scientists provides a simple means of assessing cognition, in a way that requires minimal movement on the part of the mouse. The mouse makes its response by touching its nose to the touch-sensitive screen. This means that the HD mice can complete the task, despite motor problems.
Other benefits are that it is less labour intensive, less time consuming and less stressful for mice, compared to traditional testing methods. Given the difficulties associated with these traditional methods, progress to date in trialling new treatments for cognitive deficits has been slow with contract research organisations understandably reluctant to engage with such research. Given the ease of use of the touch screen system, it is hoped this will change.
Dr Jenny Morton, Dr Lisa Saksida and Dr Tim Bussey from the Departments of Pharmacology and Experimental Psychology at the University of Cambridge, who led the research, tested normal mice and mice carrying the HD gene mutation. The task set was a choice between two visual stimuli on a touch-sensitive computer screen. If a mouse touched the correct stimulus, it was rewarded with food pellets; if it touched the incorrect stimulus, the lights went out and the mouse did not get a reward. Both normal and HD mice learnt to touch the correct stimulus with their noses and were able to learn the correct stimulus to obtain a reward by day 10.
The researchers also demonstrated that when the stimuli were reversed (so the stimulus that had previously been correct was now incorrect), HD mice struggled with the task although younger HD mice, who had not progressed as far in the disease, eventually learned it. When the mice were then presented with a new pair of stimuli, this proved too difficult even for the younger HD mice.
Importantly, and where the screen is so valuable, all the HD mice were physically able to complete the task (i.e. they were able physically to touch the screen and obtain rewards, even though their responses were often incorrect). This indicates that their poor cognitive performance was not secondary to motor impairments. It also confirms that mice with HD have cognitive problems that worsen with increasing age.
Dr Morton said, "We are very excited about the results from the touchscreen apparatus. For many HD patients, the cognitive and emotional symptoms are as disabling as the more obvious motor effects of the disease, and much effort is focused on understanding cognitive decline in HD".
"Useful cognitive testing has been a bottle-neck in developing new treatments for this aspect of HD. The touchscreen system should make it easier to test drugs for treating cognitive decline in HD."
It is hoped the touchscreen system will also be valuable for testing cognition in animals with other types of neurological dysfunction such as Alzheimer's disease or prion disease, and particularly where motor deficits make cognitive testing difficult or impractical. Dr Morton said "we are pleased at just how effective the test was and already clinical trial companies are showing an interest in the touch screen system".
Leila Coupe | EurekAlert!
Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine
Flexible sensors can detect movement in GI tract
11.10.2017 | Massachusetts Institute of Technology
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
17.10.2017 | Life Sciences
17.10.2017 | Life Sciences
17.10.2017 | Earth Sciences