|
Mice Bred to mimic schizophrenia
BBC News Saturday, 4 August 2007
US scientists have genetically modified mice to exhibit both the anatomical and behavioural defects associated with the complex condition schizophrenia. Previous studies that rely on drugs can only mimic the symptoms of the disease, such as delusions and paranoia.
As these mice matured, they became more agitated when placed in an open field, had trouble finding hidden food, and did not swim as long as regular mice - behaviours that echo the hyperactivity, smell defects and apathy observed in schizophrenia patients.
|
This mouse model will help us fill many gaps in schizophrenia research
Professor Akira Sawa
Johns Hopkins University
|
Paul Corry, of the mental health charity Rethink, said: "This is the first in a series of genetic 'breakthroughs' we are expecting to see over the next 12 months in the field of severe mental illness. "Research in this field deserves to be better funded and supported. "It is the case that schizophrenia is a complex human condition in which genes play just one part. However, this will give hope of further advances."
Read the rest of the article here
Can cats cause schizophrenia?
 December 7, 2000 issue of The Times-- It told of two American scientists who have the idea that a virus in cat droppings may cause schizophrenia.
These men plan to use a common drug to test their cat-poop concept on some people with schizophrenia. The results aren't in yet, but here's how the thinking goes:
In everyone's DNA are things called "endogenous retroviruses." They're throwbacks to infections our ancestors had and are normally harmless. But if they're activated, they slowly mess up an area of the brain known as the hippocampus. The damage doesn't show up until the brain stops growing in adolescence and it's between then and age 30 when most schizophrenia develops.
What triggers this destructive retrovirus? Psychiatrist Fuller Torrey and virologist Robert Yolken believe the culprit is something called toxoplasmosis. That's a parasite found in the faeces of about 1 percent of house cats.
This bug is killed by most people's immune systems before it causes the disease toxoplasmosis. But a pregnant woman with the parasite can transmit it to her foetus. And here's where it gets interesting. As the resulting baby grows into an adult, the parasite supposedly hides dormant in the person's brain. Then sometime between age 15 and 30, the toxoplasma comes alive, triggers the retrovirus and schizophrenia develops.
Read the whole article here
For further info see Mihms article/interview with Fuller Torrey
http://cogweb.ucla.edu/ep/Schizovirus.html
Schizophrenia, Cat Faeces And Undercooked Meat Link - Evidence Grows
En opdatering
Article Date: 23 Jan 2006
Researchers have found stronger evidence for a link between a parasite in cat faeces and undercooked meat and an increased risk of schizophrenia.
Research published today in Procedings of the Royal Society B, shows how the invasion or replication of the parasite Toxoplasma gondii in rats may be inhibited by using anti-psychotic or mood stabilising drugs.
The researchers tested anti-psychotic and mood stabilising medications used for the treatment of schizophrenia on rats infected with T. gondii and found they were as, or more, effective at preventing behaviourial alterations as anti-T. gondii drugs. This led them to believe that T. gondii may have a role in the development of some cases of schizophrenia.
Read the whole article here
Now to something from Denmark, (If anyone finds the pigs I would like to hear about it...) :)
“Danes want to create schizophrenic pigs?”
Danes want to make schizophrenic pigs (06/21/01)
Schizophrenic pigs? Yes, at least if scientists at a psychiatric unit at Bispebjerg Hospital in Denmark gets it their way. They mean pigs' brains are big enough to give appropriate results on brain scans. They also say pigs have a well developed social hierarchy, which it is thought to be very helpful, since schizophrenics often have problems with their social behaviour. They hope the experiments with the schizophrenic pigs will help them understand how schizophrenia works in humans, so they can develop methods to prevent the disease. http://www.hubin.org/media/artiklar/index_en.html#schizopigs
Schizophrenic pigs
Science 22 June 2001:
Vol. 292. no. 5525, p. 2247
Danish scientists are aiming to produce schizophrenic pigs by disrupting fetal brain development.
Past efforts to develop animal models for schizophrenia--a devastating disorder that disrupts thoughts and causes hallucinations, emotional disturbance, and social withdrawal--have been fraught with problems. Researchers have engineered rodents that exhibit stereotyped movements that are reversed by antipsychotic drugs, but they don't show the social disturbances central to the disease.
Pigs, though, are a lot like us, says psychiatrist Sidse Arnfred of Copenhagen University Hospital. Their "well-developed social hierarchy allows us to study disease-related social changes and their biological basis," she says. Pig smarts are only at the dog level, but the emotional brain or limbic system, like that of humans, is very large, says Arnfred, who is collaborating with scientists at Copenhagen's Agricultural University and Århus University Hospital.
To disrupt the fetal pigs' brain development, Arnfred will inject pregnant sows with methylazoxymethanol acetate, a toxin that stunts cell division. This, she believes, will replicate abnormalities, including sparse and disarrayed-looking cells, seen in the hippocampus of schizophrenics. The researchers will then use brain scans and behavioral tests to see if there are changes resembling those in humans. Schizophrenic pigs might be expected to withdraw socially and sink to the bottom of the social ladder, says Arnfred.
Psychiatrist Rasmus Fogh of Copenhagen's Skt. Hans Hospital says the approach makes sense in view of evidence suggesting that prenatal toxic insults may play a role in the disease. But skeptics, such as psychologist Michael Miller of the University of Missouri, Columbia, question the model's relevance, because symptoms such as hallucinations or thought disorder would be hard to assess in pigs. Also, he says, "I would expect a sick pig to have low social status no matter what the cause of its illness."
But Arnfred is optimistic. "We believe we can create a model in which a wide range of anatomical, cognitive, and behavioral characteristics are present simultaneously," she says. The scientists hope to have their first schizophrenic pigs by 2004.
High heels can cause schizophrenia!
Guardian newspaper report 2004 UK
Women watch out! Our high heels can make us crazy
MALMO (SWEDEN): The well-heeled might have cause for alarm. A scientist in Sweden says wearing high heels can lead to mental disorders, and has drawn alarming parallels between stilettos and schizophrenia among women.
Jarl Flensmark says high heels cause their wearers to tense their calves in a way that normal walking never does. That could prevent neuro-receptors in the calf muscles from triggering release of dopamine, a compound necessary for mental well-being.
"During walking, synchronised stimuli from mechanoreceptors in the lower extremities increase activity in cerebellothalamo-cortico-cerebellar loops through their action on NMDA-receptors," Flensmark wrote in a recent paper in the journal Medical Hypotheses.
"Using heeled shoes leads to weaker stimulation of the loops. Reduced cortical activity changes dopaminergic function, which involves the basal gangliathalamo-cortical-nigro-basal ganglia loops," he said.
Longterm wearing of high heels could conceivably explain why Western societies have higher rates of schizophrenia among women then do other societies where high heels are rarely worn.
Read the whole article here
|
