Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scripps research team discovers a chemical pathway that causes mice to overeat and gain weight

14.02.2007
Research could ultimately aid in development of obesity treatments through understanding the inflammatory aspects of obesity

The Scripps Research team, led by neuroscientists Manuel Sanchez-Alavez and Tamas Bartfai, discovered that mice genetically altered to lack a molecule known as the EP3 receptor tend to be more active during their normal sleep cycle and to eat more. In the study, this led to weight increases of up to 30 percent relative to mice with the receptors.

The EP3 receptor is one of four types of receptors for prostaglandin E2 (PGE2), the most important inflammatory mediator that controls a variety of physiological functions including fever, fertility, and blood pressure. The most common anti-inflammatory and analgesic treatments like ibuprofen are aimed at reducing PGE2 signaling at all four prostaglandin receptors.

The absence of EP3 receptors has long been known to prevent fever response in mice, and it was this effect that the Scripps Research team was originally studying. Previous research on mice lacking the receptors had focused on fever inhibition until mice were about three months old. The team wanted to better understand the process by studying if fever inhibition continued later in life.

... more about:
»EP3 »PGE2 »Sanchez-Alavez »receptor

When the mice were four to five months old, the researchers made a startling discovery. The older mice still did not develop fever, but the researchers noticed that these mice were gaining weight.

"The experimental mice were clearly getting heavier than their wild type litter mates, the control mice," says Sanchez-Alavez. "We realized there was something interesting going on with these animals, so we started watching their behavior at night and during the day."

During continuous monitoring of temperature and motor activity, the researchers realized that the mice without the EP3 receptors were more active during the light hours-the nocturnal mice's "night"-and, more importantly, were eating during this time. The increased activity led to higher body temperatures, but this did not burn enough extra calories to balance the additional eating, so the mice weighed 15 to 30 percent more than control mice.

Determining why the lack of EP3 receptors causes increased activity and eating will likely take a great deal of experimentation. "It's a very complex phenomenon to explore," says Sanchez-Alavez. He notes that the next step in the research will be to determine whether the obese phenotype observed in the EP3 receptor deficient mice is dependent on the lack of EP3 in the central nervous system and/or peripheral organs, as EP3 is expressed in both locations.

The research has interesting implications for scientists' understanding of appetite regulation. PGE2 is known to stimulate the release of leptin-an important hormone secreted by white fat cells and a suppressor of appetite. However, in this model, lack of EP3 did not prevent leptin increase. "Something is happening there in that circuit," says Sanchez-Alavez. "The PGE2 and leptin may be interacting and controlling eating behavior."

Bartfai notes, "Inflammation as part of the obesity and metabolic syndrome is being recognized to an increasing degree. These data directly couple the lack of a particular type of inflammatory signaling via EP3R with leptin and insulin increase, glucose tolerance, and white fat accumulation, and thus may provide a very important animal model for determining the importance of inflammation in obesity and in the conversion of obesity to type 2 diabetes."

Ultimately, better understanding of the role of EP3 receptors in feeding and obesity could lead to the development of treatments that could prevent or reverse these conditions.

Along with Sanchez-Alavez and Bartfai, Izabella Klein, Sara Brownell, Iustin Tabarean, Christopher Davis, and Bruno Conti, all of Scripps Research, were authors on the paper, "Night eating and obesity in the EP3R deficient mouse."

Marisela Chevez | EurekAlert!
Further information:
http://www.scripps.edu

Further reports about: EP3 PGE2 Sanchez-Alavez receptor

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

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

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

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

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>