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 Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin

nachricht Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care

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: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>