Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In Mice, Anxiety Is Linked to Immune System

30.10.2008
Immune cells in the brain directly influence how mice normally behave in stressful situations. The work is the first ever to genetically link mast cells to anxiety, and opens new doors for drugs that target immune cells in the brain to regulate emotions.

In the first study ever to genetically link the immune system to normal behavior, scientists at Rockefeller and Columbia universities show that mast cells, known as the pharmacologic bombshells of the immune system, directly influence how mice respond to stressful situations.

The work, to appear this week in The Proceedings of The National Academy of Sciences and to be highlighted in Science, chips away at the increasingly stale idea that the two most complex systems in the body have entirely separate modes of operation.

Eight years ago, scientists from Columbia University discovered that mast cells travel to the brain from other organs early on in development. “We now knew that mast cells resided in the brain but we didn’t know their function,” says Rockefeller University’s Donald Pfaff, head of the Laboratory of Neurobiology and Behavior. “But we know that they synthesize a large number of important chemical mediators that could potentially have severe neurophysiological effects.”

Since then, mast cells have been associated with several behaviors and conditions. For example, the number of mast cells and anxiety levels in mice have been shown to ebb and flow with the onset of stressful conditions, including asthma and food allergies. Lethargy has also been associated with an excess of mast cells. “However, we have now been the first to manipulate mast cells genetically and pharmacologically and show an immediate behavioral effect,” says Pfaff.

In their work, Pfaff and postdoc Ana Ribeiro, and the Columbia team, led by senior author Rae Silver and graduate student Kate Nautiyal, bred mice that lacked mast cells and compared their behavior in stressful situations to the behavior of mice that had a full or a moderate arsenal of mast cells. The researchers observed how willing the mice were to navigate open and lit environments and high spaces, which mice find anxiety-producing. In the wild, if a mouse is down in its own burrow, it’s not visible to predation. But if it’s bold, that is, if it has low anxiety, it will go out where it can potentially be seen by predators and hunted.

The results were striking. When the researchers placed the mice in an elevated maze with four long arms -- two simulated a canyon and the other two a cliff -- mice that lacked mast cells preferred to stay in the canyons, entering and investigating the doors to the cliffs significantly fewer times than mice with mast cells. When placed in a square box, mast cell-deficient mice preferred to scuttle against the walls, and were more hesitant to venture out to the center of the box than mice with mast cells. They also defecated more, a physiological sign of anxiety. However, the genetically different mice did not show differences in overall arousal or locomotion, suggesting that their behavioral changes were specific to their anxious state.

To confirm the behavioral and physiological differences among the genetically different mice, the researchers conducted an additional experiment. In mice that had mast cells, they used a drug that prevents sack-like granules in mast cells from busting open and releasing the array of mood and immune regulators they contain, such as serotonin, histamine, and various biochemical mediators. When the researchers targeted the drug to work specifically on mast cells in the brain, rather than in other organs, the mice showed much higher levels of anxiety-like behavior during the tests, but showed no difference in other tested physiological responses.

“The two most complicated and highly integrated systems in the body -- the immune system and the nervous system -- have been shown to be linked,” says Pfaff. “We now show that mast cells in the brain link these two systems at the level of behavior.”

Thania Benios | Newswise Science News
Further information:
http://www.rockefeller.edu

Further reports about: Mice anxiety behavior drugs genetically immune immune cells immune system mast cells stressful

More articles from Life Sciences:

nachricht New photocatalyst speeds up the conversion of carbon dioxide into chemical resources
29.05.2017 | DGIST (Daegu Gyeongbuk Institute of Science and Technology)

nachricht Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

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...

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

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>