Nicotine normalises brain activity in schizophrenia patients

January 25, 2017

Washington, Jan 25: A steady stream of nicotine normalises genetically-induced impairments in brain activity associated with schizophrenia, according to a new study that could lead to new non-addictive, nicotine-based treatments for the 51 million people worldwide who suffer from the disease.

BrainThe 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, researcher at the Institute for Behavioural Genetics (IBG) in the US.

The study found that when mice with schizophrenic characteristics were given nicotine daily, their sluggish brain 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," said Stitzel.

The scientists set out to explore the underlying 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 suggested that people with a variation in a gene called CHRNA5 are more likely to have schizophrenia, but the mechanism for that association has remained unclear. People with that variant are also more likely to smoke.

Eighty to 90 per cent of people with schizophrenia smoke and most are very heavy smokers, a fact that has long led researchers to suspect they are self-medicating.

The research team first took mice with the CHRNA5 gene variant and used state-of-the-art brain imaging technologies to see if they had hypofrontality.

Then they conducted behavioural tests to see if the mice shared key characteristics of schizophrenics, like being unable to suppress a startle response and being averse to social interaction.

The results validated that the gene variant likely plays a role in schizophrenia by causing hypofrontality, said Stitzel.

Nicotine appeared to reverse this in the mice, normalising brain activity by acting on nicotinic receptors in regions of the brain key to healthy cognitive function.

The study appears in the journal Nature Medicine.

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News Network
March 6,2020

Mar 6: The spread of the new coronavirus is shining the spotlight on a little-discussed gender split: men wash their hands after using the bathroom less than women, years of research and on-the-ground observations show.

Health officials around the world advise that deliberate, regular handwashing is one of the best weapons against the virus which causes a flu-like respiratory illness that can kill and has spread to around 80 countries.

The Centers for Disease Control and Prevention's online fact sheet "Handwashing: A corporate activity," cites a 2009 study that finds "only 31% of men and 65% of women washed their hands" after using a public restroom.

Social media comments about men's handwashing lapses forced an august British institution to caution visitors about bathroom behaviour this week.

After author Sathnam Sanghera complained on Twitter about "grown," "educated" men in the British Library toilets not washing their hands, the library responded, putting up additional signs reminding patrons to wash their hands in men's and women's bathrooms.

Thanks to "visitor feedback," a spokesman told Reuters, "we have increased further the number of posters in public toilets so that visitors are reminded of the importance of good hygiene at exactly the point where they can wash their hands."

Men and women approach handwashing after using the restroom differently, according to multiple surveys and field studies.

"Women wash their hands significantly more often, use soap more often, and wash their hands somewhat longer than men," according to a 2013 Michigan State University field study conducted by research assistants who observed nearly 4,000 people in restrooms around East Lansing, Michigan.

The study found 14.6% of men did not wash their hands at all after using the bathroom and 35.1% wet their hands but did not use soap, compared to 7.1% and 15.1% of women, respectively.

"If you stand in the men's bathroom at work, and watch men leave, they mostly don't wash their hands if they used the urinal," said one New York City public relations executive, who did not want to be identified for fear of alienating his colleagues.

Since the virus's spread, he's seen an uptick in men's handwashing at work, he noted. "I, for the record, do wash my hands all the time," he added.

Female medical staff in critical care units "washed their hands significantly more often than did their male counterparts after patient contact," a 2001 study published in the American Journal of Infection Control found.

Middle-aged women with some college education had the highest level of knowledge about hand hygiene, a survey published in 2019 by BMC Public Health, an open access public health journal, found.

Early information about coronavirus infection in China shows that men may be more susceptible to the disease. Just over 58% of the more than 1,000 COVID-19 patients reported in China through Jan. 29, 2020, were male, research published in the New England Journal of Medicine shows.

Researchers have not linked the difference to hand hygiene.

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News Network
February 4,2020

Boston, Feb 4: Practising yoga may increase levels of a messenger molecule involved in regulating brain activity, and completing one yoga class per week may maintain elevated levels of this chemical, according to a study which may lead to better ways of mitigating depressive symptoms.

The study, published in the Journal of Alternative and Complementary Medicine, assessed a group of 30 clinically depressed patients who were randomly divided into two groups.

According to the researchers, including those from Boston University in the US, both groups engaged in coherent breathing, and Iyengar yoga -- a form of hatha yoga, developed by B. K. S. Iyengar, emphasising on detail, precision, and alignment in the performance of yoga postures.

The only difference between the groups, the scientists said, was the number of 90 minute yoga sessions, and home sessions in which each group participated.

Over three months, they said, the high-dose group (HDG) was assigned three sessions per week, while the low-intensity group (LIG) engaged in two sessions per week.

The participants underwent magnetic resonance imaging (MRI) scans of their brain before the first and after the last yoga session, and also completed a clinical depression scale to monitor their symptoms, the study noted.

Results of the study revealed that both groups had improvement in depressive symptoms after three months.

Their MRI analysis showed that levels of the brain messenger molecule GABA were elevated after three months of yoga, as compared to the levels before starting yoga.

According to the study, this increase was found for approximately four days after the last yoga session, but the rise was no longer observed after about eight days.

"The study suggests that the associated increase in GABA levels after a yoga session are 'time-limited' similar to that of pharmacologic treatments such that completing one session of yoga per week may maintain elevated levels of GABA," explained study co-author Chris Streeter from Boston University.

Providing evidence-based data may help in getting more individuals to try yoga as a strategy for improving their health and well-being, the scientists said.

"A unique strength of this study is that pairing the yoga intervention with brain imaging provides important neurobiological insight as to the 'how' yoga may help to alleviate depression and anxiety," said study co-author Marisa Silveri from Harvard University.

In this study, we found that an important neurochemical, GABA, which is related to mood, anxiety, and sleep, is significantly increased in association with a yoga intervention," Silveri said.

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Agencies
June 17,2020

Leading physicians are celebrating a small dose of good news that arrived Tuesday about dexamethasone, a cheap and widely used steroid shown to be able to save lives among COVID-19 patients, but also cautioning against releasing study results by press release during a global health emergency, like in the case of the latest dexamethasone study by University of Oxford.

"It will be great news if dexamethasone, a cheap steroid, really does cut deaths by one-third in ventilated patients with COVID19, but after all the retractions and walk backs, it is unacceptable to tout study results by press release without releasing the paper", Atul Gawande, surgeon and CEO of Haven Healthcare, tweeted.

"Bottom line is, good news," Dr. Fauci, America's foremost infectious diseases expert told a US newswire on Tuesday, soon after the dexamethasone results were announced in the UK.

Fauci, who has long championed the therapeutics-first view said that dexamethasone is a "significant improvement" in the available therapeutic options currently available.

On Medical Twitter and Facebook, doctors broadly agree that dexamethasone use aligns well with the way COVID19 attacks the body's immune system. Fauci said the results in the Oxford study make "perfect sense" in that context.

"We should see the number of people who actually survive go up, if the study holds up," virologist and epidemiologist Dr. Joseph Fair told a television network.

Global coronavirus cases crossed 8 million on Tuesday. In the US, Texas and Florida are facing a new wave of cases after lifting lockdown orders earlier than medical experts recommended. Amidst the relentless graph upwards, the dexamethasone study results injected hope for better survival rates among those most seriously ill.

World Health Organization chief scientist Soumya Swaminathan welcomed the results from the randomised control trial.

Dr Eugene Gu, Founder and CEO of CoolQuit tweeted that he is "genuinely impressed" with the UK dexamethasone trial. This may be a "game changer", he wrote.

"There's no conflict of interest as dexamethasone is a generic steroid. The mechanism of action makes sense because steroids can reduce cytokine storms and overactive immune systems that makes COVID-19 so deadly. The number needed to treat is 8 ventilated patients which is great."

The Oxford study found that dexamethasone reduced deaths by 35 percent in patients who needed treatment with breathing machines and by 20 percent in those only needing supplemental oxygen. Dexamethasone was one of 5 drugs studied in a large clinical trial in the United Kingdom named RECOVERY, short for Randomised Evaluation of COVID-19 Therapy.

Peter Horby, chief investigator of the University of Oxford clinical trial, said dexamethasone is the first drug to be shown to improve survival in COVID-19. Details of the study have not been released. The trial organisers said they made their announcement via a news release because of "the public health importance of these results." According to Horby's public comments, there was a lot of initial resistance to studying steroids.

During the study, 2,104 patients were randomly selected to be given 6 milligrams of dexamethasone once a day (either by mouth or by intravenous injection) for 10 days. That group was compared with 4,321 patients who received the usual care alone.

Researchers estimated that dexamethasone would prevent one death for every eight patients treated while on ventilators and one for every 25 patients on extra oxygen alone.

UK experts have called the study results a breakthrough in the fight against the virus. The researchers have promised they would publish the results soon.

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