Previous research has indicated that women who contract flu while pregnant may give birth to babies at increased risk of schizophrenia in later life. The new study, reported in the journal Biological Psychiatry, also suggests that early use of drugs can stop the illness developing.
Scientists in Israel exposed pregnant rats to a chemical that mimics the infectious properties of a virus. Brain scans were then used to monitor the progress of their offspring. The study showed affected rat pups were normal at birth and during adolescence, but in early adulthood began to show schizophrenia-like symptoms.
A similar pattern is seen in humans, who typically experience the first signs of the disease at around the age of 20. The scans showed changes associated with schizophrenia, including enlarged ventricles – fluid-filled cavities in the brain. Treating at-risk rats with two commonly used antipsychotic drugs – risperidone and clozapine – appeared to counter the effects.
Study leader Professor Ina Weiner, from the department of psychology at Tel Aviv University, said: "If progressive brain changes occur as schizophrenia is emerging, it is possible that these changes could be prevented by early intervention. That would revolutionise the treatment of the disorder."
It was the first time the drugs had been shown to be effective as a preventative treatment, she said.
"Clinicians have suspected that these drugs can be used to prevent the onset of schizophrenia, but this is the first demonstration that such a treatment can arrest the development of brain deterioration," said Prof Weiner.
The drugs worked best when delivered during the rats' "adolescent" period, several months before they reached full maturity, she said. Currently antipsychotic drugs are only prescribed to people suffering from symptoms. Prof Weiner is now conducting further research to determine at what point changes in the brain can be detected.
Last year Scots scientists discovered a gene that could help explain the causes of mental illness. Research at Edinburgh University found the gene – ABCA13 – is partially inactive in patients with severe mental illnesses such as schizophrenia, bipolar disorder and depression.
The scientists said identifying the genes that predispose people to psychiatric illness is seen as the most important step in developing ways to tackle the conditions.
The international team of scientists, studied the genes of 2,000 psychiatric patients and compared them to 2,000 healthy people.