New Delhi:
According to a new study, it has been found that nicotine normalises generally-induced impairments in brain activity associated with schizophrenia.
In the reports, it has been found that nicotine-based treatments for 51 million people worldwide who suffer from the disease.
This new finding showed that when mice with schizophrenic characteristics were given nicotine daily, their sluggish brain activity increased within two days and within a week it was normalised.
The finding sheds light on what causes the disease and why those who have it tend to smoke heavily. It could also potentially have applications for treating addiction, Attention Deficit Hyperactivity Disorder, Bipolar disorder and other psychiatric conditions.
"Our study provides compelling biological evidence that a specific genetic variant contributes to risk for schizophrenia, defines the mechanism responsible for the effect and validates that nicotine improves that deficit," said Jerry Stitzel, a researcher at the Institute forBehavioural Genetics (IBG) in the US.
The study found that when mice with schizophrenic characteristics were given nicotine daily, their sluggish brains activity increased within two days. Within one week it had normalised. "Basically the nicotine is compensating for a genetically determined impairment. No one has ever shown that before," causes of said Stitzel.
The scientists set out to explore the and causes of "hypofrontality" a reduction of neuronal firing in the prefrontal cortex of the brain. Hypofrontality is believed to be the root cause of many of the signature cognitive problems experienced by schizophrenics, including trouble paying attention, remembering things, making decisions and understanding verbal explanations.
Previous genome-wide association studies have suggestedthat people with a variation in a gene called CHRNA5 are morelikely to have schizophrenia, but the mechanism for thatassociation has remained unclear. People with that variant arealso more likely to smoke. Eighty to 90 per cent of people with schizophrenia smokeand most are very heavy smokers, a fact that has long ledresearchers to suspect they are self-medicating.
The research team first took mice with the CHRNA5 genevariant and used state-of-the-art brain imaging technologiesto see if they had hypofrontality. Then they conducted behavioural tests to see if the miceshared key characteristics of schizophrenics, like beingunable to suppress a startle response and being averse tosocial interaction.
The results validated that the gene variant likely playsa role in schizophrenia by causing hypofrontality, saidStitzel. Nicotine appeared to reverse this in the mice, normalising brain activity by acting on nicotinic receptors inregions of the brain key to healthy cognitive function. The study appears in the journal Nature Medicine.
