Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Obesity research boosted by watching hunger in the brain

08.11.2007
Scientists can now measure how full or hungry a mouse feels, thanks to a new technique which uses imaging to reveal how neurons behave in the part of the brain which regulates appetite.

Researchers hope the technique, which uses magnetic resonance imaging, will enable a far greater understanding of why certain people become obese when others do not, and why different people have different appetites. The new study, led by researchers from Imperial College London, is described in a paper published today in the Journal of Neuroscience.

It had previously been very difficult to measure satiety, which is the psychological feeling of being full and satisfied rather than physical fullness. To judge satiety scientists have relied on asking volunteers in trials how full they feel, or watching how much food is eaten, rather than using more objective measures.

Scientists had already identified the part of the hypothalamus area of the brain which regulates appetite. In the new study, the researchers discovered that they could see the neurons there firing if they used a contrast agent of manganese ion to make the neurons visible on a magnetic resonance imaging scan.

When the mouse was hungry and hence the neurons showed increased activity, the contrast agent was taken up, making the neurons ‘light up’ on the scan. The intensity of this signal decreased as the mouse became less hungry and the neurons became less active.

Scientists already use different contrast agents to look at the anatomy of different cells in the body. The new research is the first to identify which contrast agent is taken up by the ‘hunger’ neurons and hence allow researchers to observe how they behave in response to different stimuli.

Professor Jimmy Bell, corresponding author of the study from the MRC Clinical Sciences Centre at Imperial College London, said: “Appetite and appetite control are important components of why people put on weight. We know very little about the mechanisms behind these processes and why they can vary so much between individuals. In the past we have had to rely on asking people how hungry they feel, this can be very subjective. Furthermore, sometimes your sense of satiety can be significantly affected by other factors such as your mood.

“Our new method is much more reliable and completely objective. With murine models, we can now look directly at neuronal activity in the brain. We are working on developing similar methods to study neuronal activity in the appetite centers in people,” he added.

For the study, mice given the contrast agent were also given one of two types of hormone. These were either pancreatic peptide YY (PYY), which is known to inhibit appetite, or ghrelin, which is known to increase it. The scientists then monitored the reactions of the ‘hunger’ neurons to these stimuli. As expected, the intensity of the neurons’ signals increased when ghrelin was administered and decreased with PYY.

The study was funded by the UK Medical Research Council, the Wellcome Trust, the UK Biotechnology Biological Services Research Council and the UK Department of Health.

Laura Gallagher | alfa
Further information:
http://www.imperial.ac.uk

More articles from Health and Medicine:

nachricht Infants later diagnosed with autism follow adults’ gaze, but seldom initiate joint attention
24.05.2019 | Schwedischer Forschungsrat - The Swedish Research Council

nachricht When wheels and heads are spinning - DFG research project on motion sickness in automated driving
22.05.2019 | Technische Universität Berlin

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: New studies increase confidence in NASA's measure of Earth's temperature

A new assessment of NASA's record of global temperatures revealed that the agency's estimate of Earth's long-term temperature rise in recent decades is accurate to within less than a tenth of a degree Fahrenheit, providing confidence that past and future research is correctly capturing rising surface temperatures.

The most complete assessment ever of statistical uncertainty within the GISS Surface Temperature Analysis (GISTEMP) data product shows that the annual values...

Im Focus: The geometry of an electron determined for the first time

Physicists at the University of Basel are able to show for the first time how a single electron looks in an artificial atom. A newly developed method enables them to show the probability of an electron being present in a space. This allows improved control of electron spins, which could serve as the smallest information unit in a future quantum computer. The experiments were published in Physical Review Letters and the related theory in Physical Review B.

The spin of an electron is a promising candidate for use as the smallest information unit (qubit) of a quantum computer. Controlling and switching this spin or...

Im Focus: Self-repairing batteries

UTokyo engineers develop a way to create high-capacity long-life batteries

Engineers at the University of Tokyo continually pioneer new ways to improve battery technology. Professor Atsuo Yamada and his team recently developed a...

Im Focus: Quantum Cloud Computing with Self-Check

With a quantum coprocessor in the cloud, physicists from Innsbruck, Austria, open the door to the simulation of previously unsolvable problems in chemistry, materials research or high-energy physics. The research groups led by Rainer Blatt and Peter Zoller report in the journal Nature how they simulated particle physics phenomena on 20 quantum bits and how the quantum simulator self-verified the result for the first time.

Many scientists are currently working on investigating how quantum advantage can be exploited on hardware already available today. Three years ago, physicists...

Im Focus: Accelerating quantum technologies with materials processing at the atomic scale

'Quantum technologies' utilise the unique phenomena of quantum superposition and entanglement to encode and process information, with potentially profound benefits to a wide range of information technologies from communications to sensing and computing.

However a major challenge in developing these technologies is that the quantum phenomena are very fragile, and only a handful of physical systems have been...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

 
Latest News

On Mars, sands shift to a different drum

24.05.2019 | Physics and Astronomy

Piedmont Atlanta first in Georgia to offer new minimally invasive treatment for emphysema

24.05.2019 | Medical Engineering

Chemical juggling with three particles

24.05.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>