Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biological link established between tumors and depression

19.05.2009
Animal models may help explain mood changes in cancer patients

In a study that could help explain the connections between depression and cancer, researchers at the University of Chicago have used an animal model to find, for the first time, a biological link between tumors and negative mood changes.

The team determined that substances associated with depression are produced in increased quantities by tumors and are transmitted to the brain.

Additionally, pathways that normally moderate the impact of depression-causing substances are disrupted when a tumor develops.

The research further showed that tumors induce changes in gene expression in the hippocampus, the portion of the brain that regulates emotion. Although researchers have long known that depression is a common outcome for people diagnosed with cancer, they had not known if it was brought on by a patient learning of the diagnosis or the result of treatments such as chemotherapy. Now a third source may have been identified.

"Our research shows that two types of tumor-induced molecules, one secreted by the immune system and another by the stress axis, may be responsible," said Leah Pyter, a postdoctoral fellow and lead author of a paper, "Peripheral Tumors Induce Depressive-like Behaviors and Cytokine Production and Alter Hypothalamic-Pituitary-Andrenal Axis Regulation," which is published in the current issue of the Proceedings of the National Academy of Sciences.

"Both of these substances have been implicated in depression, but neither has been examined over time frames and magnitudes that are characteristic of chronic diseases such as cancer," she said.

For their research, the team conducted a series of tests on about 100 rats, some of whom had cancer to determine their behavioral responses in tests of emotional state.

"Rats are commonly used to test drugs that are being studied for potential human benefits, such as treating depression," said Brian Prendergast, Associate Professor of Psychology at the University of Chicago, and the senior author on the study. "In this case, examining behavioral responses to tumors in non-human animals is particularly useful because the rats have no awareness of the disease, and thus their behavioral changes were likely the result of purely biological factors."

The team used tests commonly used in testing anti-depressants on rats and found that the rats with tumors became less motivated to escape when submitted to a swimming test, a condition that is similar to depression in humans. The rats with tumors also were less eager to drink sugar water, a substance that usually attracts the appetites of healthy rats.

Further tests revealed that the rats with tumors had increased levels of cytokines in their blood and in the hippocampus when compared with healthy rats. Cytokines are produced by the immune system, and an increase in cytokines has been linked to depression.

The team also found that stress hormone production also was altered in rats with tumors. The rats with tumors also had dampened production of the stress hormone corticosterone. The hormone helps regulate the impact of cytokines and reducing its production therefore increases the impact of cytokines.

The project was supported by an American Cancer Society fellowship, an NIH grant and a grant from the Brian Research Foundation.

William Harms | EurekAlert!
Further information:
http://www.uchicago.edu

More articles from Life Sciences:

nachricht Fingerprint' technique spots frog populations at risk from pollution
27.03.2017 | Lancaster University

nachricht Parallel computation provides deeper insight into brain function
27.03.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>