Research supports toxoplasmosis link to schizophrenia

Mar 11, 2009
This is a toxoplasma cyst outlined in red fluorescent cyst dye in mouse brain section. Hundreds of parasites are visible in the cyst as blue dots (nuclei stained blue) and in surrounding brain tissue. Image courtesy of E. Prandovszky

Scientists have discovered how the toxoplasmosis parasite may trigger the development of schizophrenia and other bipolar disorders.

The team from the University of Leeds' Faculty of Biological Sciences (UK) has shown that the parasite may play a role in the development of these disorders by affecting the production of dopamine - the chemical that relays messages in the controlling aspects of movement, cognition and behaviour.

, which is transmitted via cat faeces (found on unwashed vegetables) and raw or undercooked infected meat, is relatively common, with 10-20% of the UK population and 22% of the US population estimated to carry the parasite as cysts. Most people with the parasite are healthy, but for those who are immune-suppressed - and particularly for pregnant women - there are significant health risks that can occasionally be fatal.

Dr Glenn McConkey, lead researcher on the project, says: "Toxoplasmosis changes some of the chemical messages in the brain, and these changes can have an enormous effect on behaviour. Studies have shown there is a direct statistical link between incidences of and toxoplasmosis infection and our study is the first step in discovering why there is this link."

The parasite infects the brain by forming a cyst within its cells and produces an enzyme called tyrosine hydroxylase, which is needed to make dopamine. Dopamine's role in mood, sociability, attention, motivation and sleep patterns are well documented and schizophrenia has long been associated with dopamine, which is the target of all schizophrenia drugs on the market.

The team has recently received $250,000 (£160,000) to progress its research from the US-based Stanley Medical Research Institute, which focuses on mental health conditions and has a particular emphasis on bipolar illnesses.

Dr McConkey says: "It's highly unlikely that we will find one definitive trigger for schizophrenia as there are many factors involved, but our studies will provide a clue to how toxoplasmosis infection - which is more common than you might think - can impact on the development of the condition in some individuals.

"In addition, the ability of the parasite to make dopamine implies a potential link with other neurological conditions such as Parkinson's Disease, Tourette's syndrome and attention deficit disorders, says Dr McConkey. "We'd like to extend our research to look at this possibility more closely."

Source: University of Leeds

Explore further: Recorded Ebola deaths top 7,000

add to favorites email to friend print save as pdf

Related Stories

US struggles to pinpoint cyber attacks: Top official

Mar 10, 2009

The United States often cannot quickly or reliably trace a cyber attack back to its source, even as rival nations and extremists may be looking to wage virtual war, a top official warned Tuesday.

Hewlett Packard to create 500 jobs in Ireland

Mar 10, 2009

US technology company Hewlett Packard is to create 500 jobs with an 18-million-euro (23-million-dollar) expansion of its global service desk operation in Leixlip, County Kildare southwest of Dublin, Prime ...

Can mental training games help prevent Alzheimer's?

Mar 10, 2009

Loss of thinking power is a fear shared by many aging baby boomers. That fear has resulted in a budding industry for brain training products - exercises such as Brain Age, Mindfit and My Brain Trainer - which in 2007 generated ...

Recommended for you

Recorded Ebola deaths top 7,000

12 hours ago

The worst Ebola outbreak on record has now killed more than 7,000 people, with many of the latest deaths reported in Sierra Leone, the World Health Organization said as United Nations Secretary-General Ban ...

Liberia holds Senate vote amid Ebola fears (Update)

17 hours ago

Health workers manned polling stations across Liberia on Saturday as voters cast their ballots in a twice-delayed Senate election that has been criticized for its potential to spread the deadly Ebola disease.

Evidence-based recs issued for systemic care in psoriasis

Dec 19, 2014

(HealthDay)—For appropriately selected patients with psoriasis, combining biologics with other systemic treatments, including phototherapy, oral medications, or other biologic, may result in greater efficacy ...

Bacteria in caramel apples kills at least four in US

Dec 19, 2014

A listeria outbreak believed to originate from commercially packaged caramel apples has killed at least four people in the United States and sickened 28 people since November, officials said Friday.

Steroid-based treatment may answer needs of pediatric EoE patients

Dec 19, 2014

A new formulation of oral budesonide suspension, a steroid-based treatment, is safe and effective in treating pediatric patients with eosinophilic esophagitis (EoE), according to a new study in Clinical Gastroenterology and Hepatology, the official clinical practice journal ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.