Featured Research

from universities, journals, and other organizations

Common parasite may trigger suicide attempts: Inflammation from T. gondii produces brain-damaging metabolites

Date:
August 16, 2012
Source:
Michigan State University
Summary:
A parasite thought to be harmless and found in many people may actually be causing subtle changes in the brain, leading to suicide attempts. New research adds to the growing work linking an infection caused by the Toxoplasma gondii parasite to suicide attempts.

The Toxoplasma gondii parasite has been linked to inflammation in the brain, damaging cells.
Credit: Image courtesy of Michigan State University

A parasite thought to be harmless and found in many people may actually be causing subtle changes in the brain, leading to suicide attempts.

New research appearing in the August issue of The Journal of Clinical Psychiatry adds to the growing work linking an infection caused by the Toxoplasma gondii parasite to suicide attempts. Michigan State University's Lena Brundin was one of the lead researchers on the team.

About 10-20 percent of people in the United States have Toxoplasma gondii, or T. gondii, in their bodies, but in most it was thought to lie dormant, said Brundin, an associate professor of experimental psychiatry in MSU's College of Human Medicine. In fact, it appears the parasite can cause inflammation over time, which produces harmful metabolites that can damage brain cells.

"Previous research has found signs of inflammation in the brains of suicide victims and people battling depression, and there also are previous reports linking Toxoplasma gondii to suicide attempts," she said. "In our study we found that if you are positive for the parasite, you are seven times more likely to attempt suicide."

The work by Brundin and colleagues is the first to measure scores on a suicide assessment scale from people infected with the parasite, some of whom had attempted suicide.

The results found those infected with T. gondii scored significantly higher on the scale, indicative of a more severe disease and greater risk for future suicide attempts. However, Brundin stresses the majority of those infected with the parasite will not attempt suicide: "Some individuals may for some reason be more susceptible to develop symptoms," she said.

"Suicide is major health problem," said Brundin, noting the 36,909 deaths in 2009 in America, or one every 14 minutes. "It is estimated 90 percent of people who attempt suicide have a diagnosed psychiatric disorder. If we could identify those people infected with this parasite, it could help us predict who is at a higher risk."

T. gondii is a parasite found in cells that reproduces in its primary host, any member of the cat family. It is transmitted to humans primarily through ingesting water and food contaminated with the eggs of the parasite, or, since the parasite can be present in other mammals as well, through consuming undercooked raw meat or food.

Brundin has been looking at the link between depression and inflammation in the brain for a decade, beginning with work she did on Parkinson's disease. Typically, a class of antidepressants called selective serotonin re-uptake inhibitors, or SSRIs, have been the preferred treatment for depression. SSRIs are believed to increase the level of a neurotransmitter called serotonin but are effective in only about half of depressed patients.

Brundin's research indicates a reduction in the brain's serotonin might be a symptom rather than the root cause of depression. Inflammation, possibly from an infection or a parasite, likely causes changes in the brain's chemistry, leading to depression and, in some cases, thoughts of suicide, she said.

"I think it's very positive that we are finding biological changes in suicidal patients," she said. "It means we can develop new treatments to prevent suicides, and patients can feel hope that maybe we can help them.

"It's a great opportunity to develop new treatments tailored at specific biological mechanisms."

Brundin and co-senior investigator Teodor Postolache of the University of Maryland led the research team. Funding for the project came from several sources, most notably the Swedish Research Council and American Foundation for Suicide Prevention.


Story Source:

The above story is based on materials provided by Michigan State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Yuanfen Zhang, Lil Trδskman-Bendz, Shorena Janelidze, Patricia Langenberg, Ahmed Saleh, Niel Constantine, Olaoluwa Okusaga, Cecilie Bay-Richter, Lena Brundin, Teodor T. Postolache. Toxoplasma gondiiImmunoglobulin G Antibodies and Nonfatal Suicidal Self-Directed Violence. The Journal of Clinical Psychiatry, 2012; DOI: 10.4088/JCP.11m07532

Cite This Page:

Michigan State University. "Common parasite may trigger suicide attempts: Inflammation from T. gondii produces brain-damaging metabolites." ScienceDaily. ScienceDaily, 16 August 2012. <www.sciencedaily.com/releases/2012/08/120816170400.htm>.
Michigan State University. (2012, August 16). Common parasite may trigger suicide attempts: Inflammation from T. gondii produces brain-damaging metabolites. ScienceDaily. Retrieved August 23, 2014 from www.sciencedaily.com/releases/2012/08/120816170400.htm
Michigan State University. "Common parasite may trigger suicide attempts: Inflammation from T. gondii produces brain-damaging metabolites." ScienceDaily. www.sciencedaily.com/releases/2012/08/120816170400.htm (accessed August 23, 2014).

Share This




More Mind & Brain News

Saturday, August 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) — According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
Powered by NewsLook.com
Do More Wedding Guests Make A Happier Marriage?

Do More Wedding Guests Make A Happier Marriage?

Newsy (Aug. 20, 2014) — A new study found couples who had at least 150 guests at their weddings were more likely to report being happy in their marriages. Video provided by Newsy
Powered by NewsLook.com
Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) — Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) — Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins