London: Cold sore virus could lead to cognitive symptoms characteristic to schizophrenia patients, research led by Johns Hopkins scientists has found.
Dr. David J. Schretlen and colleagues found that exposure to cold sore virus may be partially responsible for shrinking regions of the brain and the loss of concentration skills, memory, coordinated movement and dexterity widely seen in patients with schizophrenia.
"We`re finding that some portion of cognitive impairment usually blamed solely on the disease of schizophrenia might actually be a combination of schizophrenia and prior exposure to herpes simplex virus 1 infection, which reproduces in the brain," said Schretlen.
The research could lead to new ways to treat or prevent the cognitive impairment that typically accompanies this mental illness, including with antiviral drugs, the scientists say.
Doctors have long known that cognitive impairment, including problems with psychomotor speed, concentration, learning, and memory, are prevalent features of schizophrenia.
Cognitive deficits often surface months to years before symptoms that are traditionally used to diagnose this disease, such as delusions or hallucinations.
Some previous studies have shown that schizophrenic patients with antibodies to herpes simplex virus 1 (HSV-1), the virus that causes cold sores, often have more severe cognitive deficits than patients without these antibodies.
Other studies have shown that patients with HSV-1 antibodies have decreased brain volumes compared to patients without the antibodies.
However, it has been unclear whether the cognitive deficits are directly related to the decreased brain volume.
To investigate, the researchers recruited 40 schizophrenic patients from outpatient clinics at the Johns Hopkins and Sheppard Enoch Pratt hospitals in Baltimore, Md.
Blood tests showed that 25 of the patients had antibodies for HSV-1 and 15 didn`t.
The researchers gave all of the patients tests to measure speed of coordination, organizational skills and verbal memory.
The patients then underwent MRI brain scans to measure the volume of particular regions of their brains.
As in previous studies, results showed that patients with antibodies to HSV-1 performed significantly worse on the cognitive tests than patients without the antibodies.
But expanding on those earlier studies, analysis of the brain scans showed that the same patients who performed poorly on the tests also had reduced brain volume in the anterior cingulate, which controls processing speed and the ability to switch tasks.
There was also shrinkage in the cerebellum, which controls motor function.
The results suggest that HSV-1 might be directly causing the cognitive deficits by attacking these brain regions, said Schretlen.
The researchers said that the results already suggest new ways of treating the disorder.
Data from other studies has shown that antiviral medications can reduce psychiatric symptoms in some patients with schizophrenia.
"If we can identify schizophrenic patients with HSV-1 antibodies early on, it might be possible to reduce the risk or the extent of cognitive deficits," he added.
The study has been published in the May Schizophrenia Research.
New Delhi: A day after Home Minister P Chidambaram said Maoists could be behind the attack on Jnaneswari Express, Railway Minister Mamata Banerjee Tuesday said she was not sure about the involvement of the Left-wing
"I do not know whether it is Maoists who were behind
the attack. But whoever is behind the attack should be
punished," Banerjee told reporters here.
She said she does not want to comment further on the
issue before the investigation is over.
"I am not a political astrologer. I cannot say anything
before investigation," she said.
Chidambaram yesterday said the needle of suspicion
pointed to Maoists or their frontal organisations.
The Railways has asked for a CBI probe into the
incident which claimed 149 lives. However, the state government
has not favoured such an idea.
"The matter of CBI probe is under the consideration of
Ministry of Home Affairs," Banerjee said.
The priority before the government is to ensure
passengers` safety and security, she said.
Banerjee termed the incident as a brutal murder of
innocent people and said the government will do everything to
punish the culprits.
On May 28, 13 coaches of the Maharashtra-bound express
were derailed and the train was later hit by a goods train coming from
the opposite direction.
Asked about the police firing incident in West Bengal
during yesterday`s civic body polls in which one person was
killed, the Trinamool Congress chief said her party activists
should not be blamed for it and held Chief Minister Buddhadeb
"It is the Chief Minister`s constituency. The CM allowed
the goons to rig the elections. It is their internal fight.
They did not allow the Trinamool workers and candidates to be
there. TC does not know anything," she said.