Tuesday, October 17, 2023

AMERIKA

National Poll: Parents of elementary-aged children may engage in more helicopter parenting than they think


Report suggests gap between what parents say about fostering children’s independence and what tasks they actually let their kids do without them


Reports and Proceedings

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

Do children have enough independence? 

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REPORTS SUGGESTS SIZABLE GAP BETWEEN PARENT ATTITUDES ABOUT PROMOTING CHILDREN’S INDEPENDENCE AND WHAT THEY ACTUALLY ALLOW OR ENCOURAGE THEIR CHILDREN TO DO WITHOUT SUPERVISION.

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CREDIT: UNIVERSITY OF MICHIGAN HEALTH C.S. MOTT CHILDREN’S HOSPITAL NATIONAL POLL ON CHILDREN’S HEALTH




ANN ARBOR, Mich. –  As they grow, children start doing certain activities without their parents watching over them, including trick-or-treating with friends, staying home alone or biking to a friend’s house.

And while most parents agree that kids benefit from opportunities to be independent, they may be engaging in more “helicopter parenting” than they realize, suggests a new University of Michigan Health C.S. Mott Children’s Hospital National Poll on Children’s Health.

“There’s a sizable gap between parent attitudes about promoting children’s independence and what they actually allow or encourage their children to do without supervision,” said Mott Poll co-director Sarah Clark, M.P.H.

“This suggests some parents may be missing opportunities to guide their children in tasks of autonomy and unintentionally hindering kids’ development of independence and problem-solving skills.”

Four in five parents of children ages 9-11 agree that it’s good for children to have free time without adult supervision. But fewer report their child actually does certain things without an adult present, the poll suggests.

About three in five parents have let their tween-aged child stay home for 30-60 minutes while half say their child has separated from them to find an item at another aisle in the store. Less than half say their child has waited in the car while the parent runs a quick errand, walked or biked to a friend’s house or played at the park with a friend, and less than a sixth of parents have let their child trick-or-treat with friends.

The top reason behind parents’ hesitancy to promote such independent milestones was safety. Yet, while a little more than half worried someone might scare or follow their child, just 17% of parents say their neighborhood is not safe for children to be alone.

“To some extent, worrying about your child is natural. But some parents are limiting their child’s independent activities due to highly publicized media reports, even if those outcomes are very unlikely to occur or cannot be prevented,” Clark said.

“Parents can ease in with small steps such as letting their child spend time with a friend at a familiar public place. Discussions before and after can help parents assess if their kids understand the importance of following safety rules.”

Other parents say they keep children from taking on such tasks alone because they don’t believe they’re ready while some parents believe state or local laws don’t allow children that age to be alone and that someone might call the police. A little more than one in 10 parents also think others will think they are a bad parent if their child is seen unsupervised.

Over half of parents say that unsupervised children cause trouble while a quarter have criticized another parent, and 13% have been criticized for not adequately supervising their child.

“Parents may be affected by ‘blame culture’ – the expectation that they will be criticized if something happens to their child,” Clark said.  

The poll report also suggests a disconnect between what parents of younger children ages 5-8 say and what they do in fostering independence.

Nearly three quarters say they make it a point to have their child do things themselves. But less than half of these parents say their child regularly engages in actions such as talking with the doctor or nurse at health visits, deciding how to spend allowance or gift money, speaking to unfamiliar adults in business situations, such as ordering at a restaurant, or preparing their own meal or snack.

Among reasons were safety, getting stuck in habits, the parent belief that their child doesn’t want to do things themselves or isn’t mature enough, thinking it will take too long or that it won’t be done in the parent’s preferred way.

The elementary school years, Clark notes, is an important phase for developing independence with parental guidance.

“Becoming independent is a gradual process of allowing children increasing amounts of freedom, with parents there to teach skills and help the child understand the consequences of their choices,” Clark said.

“As children become more experienced and comfortable with tasks, they can assume responsibility for doing them regularly. Research shows encouraging independence fosters a child’s self-confidence, resilience, problem-solving ability, and mental health.”

The nationally representative poll is based on responses from 1,044 parents of children 5-11 years surveyed in August.

 

Treating high-risk drinking, alcohol use disorder: new Canadian guideline


CANADIAN MEDICAL ASSOCIATION JOURNAL




A new Canadian guideline for treating high-risk drinking and alcohol use disorder (AUD) with 15 evidence-based recommendations to reduce harms associated with high-risk drinking and to support people’s treatment and recovery from AUD is published in CMAJ (Canadian Medical Association Journalhttps://www.cmaj.ca/lookup/doi/10.1503/cmaj.230715.

High-risk drinking, AUD and alcohol-related harms are common in Canada. Nearly 18% of people aged 15 years or older in Canada will meet the clinical criteria for an AUD in their lifetime, and over 50% of people in Canada aged 15 years or older currently drink more than the amount recommended in Canada’s Guidance on Alcohol and Health.

Despite the high prevalence of high-risk drinking and AUD, these conditions frequently go unrecognized and untreated in the health care system. Even if recognized, AUD does not receive evidence-based interventions. It’s estimated that less than 2% of eligible patients receive evidence-based alcohol treatment in the form of evidence-based pharmacotherapies, likely owing to low awareness. Conversely, according to the guideline, many Canadian patients receive medications that may be ineffective and potentially harmful.

Guideline developed in partnership with Canadian Research Initiative on Substance Misuse

To address this health issue, Health Canada funded the Canadian Research Initiative on Substance Misuse (CRISM) and the BC Centre on Substance Use (BCCSU) to develop the “Canadian Guideline for the Clinical Management of High-Risk Drinking and Alcohol Use Disorder.” The guideline provides recommendations for the clinical management of high-risk drinking and AUD to support primary health care providers to implement evidence-based screening and treatment interventions.

The guideline, developed by a 36-member committee, is based on the latest evidence, expert consensus, and lived and living experience, as well as clinical experience from across Canada. It makes 15 recommendations for care providers about how to ask about alcohol, diagnose AUD, manage alcohol withdrawal, and create treatment plans based on the individual’s goals. These treatment plans can include medications, counselling, harm reduction or a combination.

“High-risk drinking and alcohol use disorder frequently go unrecognized and untreated in our health care system, leaving individuals without access to effective treatments that can improve their health and well-being,” says Dr. Jürgen Rehm, co-chair of the guideline writing committee and senior scientist in the Institute for Mental Health Policy Research at the Centre for Addiction and Mental Health (CAMH), Toronto, Ontario. “These guidelines give primary care providers the tools to support early detection and treatment, and connect patients and families with specialized care services and recovery-oriented supports in their communities.”

The website Helpwithdrinking.ca will be available to raise awareness of resources and treatments available to people in Canada based on the new guidelines.

Practice article highlights potential harms of prescribing medications not recommended in guideline

A related practice article https://www.cmaj.ca/lookup/doi/10.1503/cmaj.231015 highlights the complexity of providing treatment to patients with AUD and the possible negative effects of selective serotonin reuptake inhibitor (SSRI) therapy, which can worsen the disease in some people.

“Although the initiation of an SSRI appeared to be a likely explanation for the escalation in this patient’s alcohol use, other factors may also have played an important role,” writes Dr. Nikki Bozinoff, associate scientist at CAMH, with co-authors. “This case illustrates that although it may be common practice to prescribe SSRIs for people with AUD, SSRIs may not be effective for depressive symptoms in people with concurrent active AUD, and may worsen alcohol use in some.”

The guideline recommends against SSRI antidepressants in patients with AUD, or AUD and concurrent anxiety or depression.

“Despite the burden of illness, there remains a tremendous gap between what we know is effective treatment and the care Canadians are actually receiving,” says Dr. Evan Wood, co-chair of the guideline writing committee and an addiction medicine specialist. “Unfortunately, in the absence of effective care, people are being routinely prescribed potentially harmful medications that can, unknown to most prescribers, actually increase alcohol use in some patients. These guidelines seek to close that gap and ensure Canadians are accessing the safest and most effective treatments that meet their needs.”

 

Local retail outlets for legal marijuana may be associated with alcohol co-use among high school students: Study


Peer-Reviewed Publication

JOURNAL OF STUDIES ON ALCOHOL AND DRUGS

Retail marijuana outlet 

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RETAIL MARIJUANA OUTLET

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CREDIT: JOURNAL OF STUDIES ON ALCOHOL AND DRUGS




PISCATAWAY, NJ—Given the increasing trend toward legalizing marijuana in many states, there is growing concern that underage youth may find the drug easier to access. In fact, a recent study reported in the Journal of Studies on Alcohol and Drugs suggests that in areas with local retail availability of legalized marijuana, high school students are more likely to use marijuana and alcohol together, as well as alcohol alone.

“Greater retail availability may ‘normalize’ marijuana use for young people, even if they are unable to purchase marijuana directly from retail businesses, and retail sales may introduce greater access through social sources,” says study lead author Sharon O’Hara, Dr.P.H., lecturer at the University of California Berkeley School of Public Health and associate research scientist at the Pacific Institute for Research and Evaluation.

For their research, O’Hara and colleagues used info from the 2010-2011 and 2018-2019 California Healthy Kids Surveys of 9th and 11th graders in 554 public high schools in 38 California cities. Students were asked how often they used marijuana and alcohol over the previous 30 days.

The researchers also calculated the density of marijuana and cannabis retail outlets in each area (the number of outlets per square mile within the city limits).

Among the full sample, O’Hara and colleagues found a significant interaction between recreational marijuana legalization and marijuana outlet density, indicating a greater increase in the likelihood of alcohol use and co-use of alcohol and marijuana in cities with higher retail availability of cannabis after the passage of recreational marijuana legalization. A positive association between recreational marijuana legalization and marijuana use was found in cities at all levels of marijuana outlet density.

That outcome was expected, but a closer look at the data found some surprising results.

“We were most surprised by the effects of recreational marijuana legalization on the co-use of alcohol and marijuana by subgroups of alcohol users versus cannabis users,” says O’Hara. “We found significant positive associations between recreational marijuana legalization and co-use for past-30-day drinkers but significant inverse associations between recreational marijuana legalization and co-use among past-30-day marijuana users.”

The researchers hypothesize that, since its legalization, marijuana use has been increasing in the general population of California adolescents, while alcohol use continues to decrease.

Given that, among the full sample of high school students, the effect of recreational marijuana legalization was strongest in the cities with relatively high marijuana outlet density, attention should be paid to policies that limit the retail availability of marijuana, says O’Hara.

“Regulatory policies can be considered at the state level and in local jurisdictions with zoning authority over retail marijuana businesses,” she says. “So, even if your state legalizes recreational marijuana, you may have the ability to regulate the number and location of retail marijuana businesses using local land use authority.”

As marijuana outlets and retail sales become as commonplace as alcohol stores, O’Hara and her co-researchers have concerns about the effects on high school students.

The researchers hope their findings help to inform future research on the possible effects of recreational marijuana legalization and marijuana retail outlet density on alcohol and marijuana co-use and guide investigations into the mechanisms underlying these associations.

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O’Hara, S. E., Paschall, M. J., & Grube, J. W. (2023). Recreational marijuana legalization, local retail availability, and alcohol and marijuana use and co-use among California high school students. Journal of Studies on Alcohol and Drugs, 84, 734–743. doi: 10.15288/jsad.22-00277

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To arrange an interview with Sharon O’Hara, Dr.P.H., please contact her at sohara@prev.org.

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The Journal of Studies on Alcohol and Drugs (jsad.com) is published by the Center of Alcohol & Substance Use Studies (alcoholstudies.rutgers.edu) at Rutgers, The State University of New Jersey. It is the oldest substance-related journal published in the United States.

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The Journal of Studies on Alcohol and Drugs considers this press release to be in the public domain. Editors may publish this press release in print or electronic form without legal restriction. Please include a byline and citation.

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To view the public domain, stock-photo database of alcohol, tobacco and other drug-related images compiled by the Journal of Studies on Alcohol and Drugs, please visit www.jsad.com/photos.

 

 

Marine bacteria take a bite at plastic pollution


A bacterium found in the sea can degrade a plastic that otherwise resists microbial breakdown in marine environments

Peer-Reviewed Publication

HOKKAIDO UNIVERSITY

Vibrio ruber 

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VIBRIO RUBER (BOTTOM LEFT) WAS SHOWN TO DEGRADE PBS.

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CREDIT: YUTARO KIMURA ET AL., ENVIRONMENTAL MICROBIOLOGY, SEPTEMBER 29, 2023.




Joint press release by Hokkaido University and the Mitsubishi Chemical Group

A bacterium that can degrade the common polymer polybutylene succinate (PBS), which naturally biodegrades to only a limited extent in marine environments, could lead to improved ways to recycle this polymer. The bacterium’s potential, and its enzyme molecule that breaks down PBS, was discovered by researchers at Hokkaido University, working with colleagues at the Mitsubishi Chemical Group in Japan. The team published their results in the journal Environmental Microbiology.

PBS is generally regarded as an eco-friendly polymer due to its biodegradability when discarded on land and exposed to the atmosphere. This has led to its increasing use since the early 1990s in industrial plastics, including mulching films, compostable bags and catering packaging. But many discarded plastics eventually find their way into the sea, and unfortunately PBS does not biodegrade well in that environment.

“Plastic pollution in the ocean is a global problem and we need to tackle it by gaining new understanding of plastic behaviour in that environment, and new technologies to deal with the pollution,” says Tomoo Sawabe, leader of the research team at Hokkaido University’s Faculty of Fisheries Sciences.

As only a small number of marine microorganisms able to biodegrade PBS had been discovered previously, Sawabe and his colleagues set out to try to find others and with better activity.

They examined the effect on PBS of microbes gathered from natural seawater off Japan, allowing them to identify several types of marine bacteria that could degrade it. They also identified the enzyme responsible for degrading PBS in a specific strain of bacteria called Vibrio ruber. They named the enzyme PBSase.

They then took things further by using molecular biological techniques to insert the gene for PBSase into the common bacterium Escherichia coli, which they cultured to produce highly purified samples of the enzyme for further study.

“Elucidating the degradation mechanism in seawater at the molecular level may lead to the development of new marine biodegradable polymers,” says Yasuhito Yamamoto, Sawabe’s collaborator at Mitsubishi Chemical Corporation of the Mitsubishi Chemical Group. “This enzyme could be used as a decomposition accelerator or catalyst for chemical recycling of collected waste plastics.”

The availability of the purified enzyme also allowed the researchers to examine its structure, with simulations suggesting it was closely related to a different enzyme known to degrade another common polymer: polyethylene terephthalate (PET).

“By exploring the enzyme’s activity in degrading other polymers, such as PET, we hope that our work will contribute more widely to advances in plastic recycling technologies,” Sawabe concludes.

This research is part of wider efforts to address the complexity of biodegradable polymer technologies caused by their differing biodegradability on land and in the sea. By learning more about what controls biodegradability in different environments, scientists will hopefully develop polymers that are best suited to the environments they are used in, and those that they may end up in after use.

A protein structure comparison between PBSase (pink gold backbone) and PET degrading enzyme PET6 (cobalt backbone). The catalytic centers are indicated by magenta and green. PET binding residues of PET6 are shown in yellow.

CREDIT

Yutaro Kimura et al., Environmental Microbiology, September 29, 2023.

 

The emotional function of dreams is not the same everywhere


By comparing the dreams of Western and non-Western populations, a study by the UNIGE and the University of Toronto shows that dreams can have a variable emotional function


Peer-Reviewed Publication

UNIVERSITÉ DE GENÈVE



Why do we dream? A product of our brain’s neurophysiology, dreaming is a complex experience that can take on many emotional tones and simulate reality to varying degrees. As a result, there is still no clear answer to this question. A study led by the universities of Geneva (UNIGE) and Toronto, and the Geneva University Hospitals (HUG), compared the dreams of two forager communities, in Tanzania and the Democratic Republic of Congo, with those of individuals living in Europe and North America. It showed that the first two groups produced more threatening, but also more cathartic and socially-oriented dreams than the Western groups. These results, to be read in Scientific Reports, show how strong are the links between the socio-cultural environment and the function of dreams.


Dreaming is a hallucinatory experience common to all human beings. It occurs most often during the paradoxical phase of sleep, known as the Rapid Eye Movement (REM) phase. However, it can occur at any sleep stage. What are the physiological, emotional or cultural functions of dreams? Does it regulate our emotions? Does it prepare us to deal with a specific situation? Recent theories suggest that during a ‘‘functional’’ dream, the individual simulates more threatening and/or social situations, which would have an evolutionary advantage in promoting adapted behaviour to real-life situations.


The outcome of dreams differs depending on the environment and the population studied

To test these theories, researchers from the UNIGE and the University of Toronto compared the content of the dreams of the BaYaka in the Democratic Republic of Congo and the Hadza in Tanzania - two communities whose way of life is close to that of our hunter-gatherer ancestors - with that of different groups of individuals living in Europe and North America (Switzerland, Belgium, Canada), including healthy participants and patients with psychiatric disorders. For the BaYaka and Hadza, dream narratives were collected over a two-month period in the field by anthropologists from the University of Toronto. The data on the dreams of the Western groups came from past studies, published between 2014 and 2022.


‘‘We discovered that the dreams of the BaYaka and Hadza are very dynamic. They often begin with a situation of danger, in which life is threatened, but end up staging a means of coping with this threat, unlike the scenarios in the Western groups we observed. On the other hand, in clinical populations - such as patients suffering from nightmares or social anxiety - the dreams are intense but do not contain a cathartic emotional resolution. In these latter groups, the adaptive function of dreaming seems to be deficient,’’ explains Lampros Perogamvros, a privat-docent and group leader in the Departments of Psychiatry and Basic Neurosciences at the UNIGE Faculty of Medicine, and an attending physician at the HUG Center for Sleep Medicine, who led the study.


A mirror of the social fabric

Among the responses available to indigenous people when faced with a threat in their dreams, the researchers found that those linked to social support were very frequent. This is the case, for example, when an indigenous person reports a dream in which he is hit by a buffalo in the middle of the bush, only to be rescued by a member of his community. Or when another dreams that he falls into a well and one of his friends helps him out. These dreams contain their own emotional resolution.


'‘Among the BaYaka and Hadza, the social bonds they have are, by necessity, very strong. Compared to the more individualist societies in Europe and North America, day to day life and division of labor is typically more egalitarian. It appears this kind of social connection, and reliance on community means that the best way they process the emotional content associated with threat in their dreams, is by way of the social relationships they have. In effect these relationships are the emotional tools used to process life’s challenges,’’ explains David Samson, Associate Professor of Evolutionary Anthropology at the University of Toronto, Mississauga, and first author of the study. The research team therefore suggests that there is a close connection between the function of dreams and the societal norms and values of each specific society studied.


‘‘However, it is difficult to deduce any causal links between the dreams and daytime functioning in this study. Nor should we conclude that dreams in groups of Western individuals have no emotional function,’’ Lampros Perogamvros adds. In fact, in 2019, the same research team published a study showing that ‘‘bad dreams’’ in Western individuals, i.e. dreams with a negative content that are not nightmares, are often simulations of our fears that prepare us to face them once we are awake. ‘‘There seems to be more than one type of ‘functional’ dreams. The present study shows that there is a strong link between our socio-cultural life and the function of dreams,’’ concludes the researcher.

 

USTC constructs global variable-resolution atmospheric physico-chemical coupling simulation framework


using atmospheric sand and dust as a case study.

Peer-Reviewed Publication

UNIVERSITY OF SCIENCE AND TECHNOLOGY OF CHINA




A research team led by Prof. ZHAO Chun from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) has developed a global variable-resolution modeling framework and conducted research using atmospheric sand and dust as a case study. The results were published in Journal of Advances in Modeling Earth Systems.

Atmospheric dust aerosols play a critical role in the Earth's climate system. However, numerical modeling of dust aerosols still faces significant uncertainties due to limitations in horizontal resolution. Previous studies have typically employed downscaling methods for regional high-resolution simulations. But this approach can introduce boundary issues and restrict the interaction between regional atmospheric dust and large-scale circulation.

Simulating dust aerosols using a global variable-resolution atmospheric model with regional refinement capabilities offers an alternative that avoids the use of boundary conditions and is computationally more efficient than a global high-resolution model.

In this study, the research team constructed a framework for modeling segmented refined aerosols and their feedback effects based on the power kernel of the global variable-grid atmospheric model MPAS. The model provides a more accurate spatial distribution of dust and sand compared to observations and previous studies.

Furthermore, this research achieved the first dust simulation at a convectively resolved scale (4km) within a global framework. The results indicate that convectively resolved scale simulations enhance the wet scavenging efficiency of dust and reduce the dust mass concentration by resolving the convective precipitation process.

This study presents a new model framework that allows us to uncover the mechanisms behind aerosol impacts on regional and global weather and climate systems. Building on this foundation, future work will continue to develop physical and chemical parameterizations, optimize AI-based model performance, and delve deeper into these mechanisms.

Paper Link: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023MS003636

Contact:

Jane FAN Qiong

Tel: +86-551-63607280

E-mail:englishnews@ustc.edu.cn

 

The number of chickenpox cases in children in Finland fell rapidly after the launch of the vaccination program


Finland was the first Nordic country to start a chickenpox vaccination program

Peer-Reviewed Publication

FINNISH INSTITUTE FOR HEALTH AND WELFARE




A recent study by the Finnish Institute for Health and Welfare (THL) reveals that a two-dose varicella vaccination programme to all children under the age of 12 who had not had chickenpox reduced the number of health centre appointments related to the disease significantly and fast in all age groups. The number of health centre appointments of children under the age of 12 decreased by more than 95% in 2022 compared with the time before the vaccinations. The number of chickenpox cases among unvaccinated children under the age of one also decreased by 87%, which suggests herd protection of the vaccinations. 

The varicella vaccination programme was launched in Finland in September 2017. The varicella vaccination programme includes doses at the ages of 18 months and 6 years. In addition, extensive so-called catch-up vaccinations were carried out during the first year, offering the vaccine to all those under the age of 12 who had not had chickenpox. 

“For example, while 3-year-olds had more than 1,000 cases of chickenpox requiring contact with primary healthcare every year before the vaccination programme, there have been only a few dozen cases per year in the past few years,” says Heini Salo, Senior Researcher at THL. 

“It should also be noted that the majority of young children's chickenpox cases do not require contact with healthcare. However, it is likely that, as the circulation of the virus has decreased, the number of chickenpox cases treated at home has also decreased,” Salo continues.  

Finland was the first Nordic country to start a chickenpox vaccination programme

Finland was the first Nordic country to start a chickenpox vaccination programme, and the vaccinations for all children under the age of 12 who had not had chickenpox were exceptionally extensive. In the first year of the vaccination programme, a quarter of a million children were vaccinated. 

Between 2017 and 2022, 85–87% of children received the first vaccine dose. Information on the coverage of the second dose is available only on those born in 2016. It was 58% in 2022. 

The catch-up vaccinations were also well accepted. Based on previous studies, it is known that 23% of 5–9-year-olds, for example, had not had chickenpox. However, the vaccination coverage in this age group was 33%, which was clearly higher than expected. 

There is still room for improvement in the coverage of chickenpox vaccinations. 

“At the moment, more than one in ten children in all the age groups do not get vaccinated. The accumulation of people susceptible to chickenpox in the population means that chickenpox epidemics are likely to occur in the future," Salo says. 

“Children who are not vaccinated may catch chickenpox as adults when travelling abroad, for example. Chickenpox is significantly more serious in adults than in children and practically always leads to a doctor's appointment and medication.” 

The study was carried out by examining the national register data in primary healthcare. 

 

Link between seasons and eating habits

Peer-Reviewed Publication

UNIVERSITY OF COPENHAGEN - THE FACULTY OF HEALTH AND MEDICAL SCIENCES




The number of hours of light exposure we experience affects how we eat and how we burn energy. This may help us understand the link between seasons and metabolism.

You might imagine that you're healthier in the summer. The sun is shining, we get plenty of vitamin D, and the days are long.

However, recent research from the University of Copenhagen suggests that eating habits in winter may be better for our metabolic health than eating habits in summer, at least if you’re a mouse. Researchers have examined the metabolism and weight of mice exposed to both ‘winter light’ and ‘summer light’.

“We found that even in non-seasonal animals, differences in light hours between summer and winter do cause differences in energy metabolism. In this case, body weight, fat mass and liver fat content,” says Lewin Small, who carried out the research while a postdoc at Novo Nordisk Foundation Center for Basic Metabolic Research at the University of Copenhagen. He adds:

“We found this mostly in mice exposed to winter light hours. These mice had less body weight gain and adiposity. They have more rhythmicity in the way they eat over a 24-hour period. And this then led to benefits in metabolic health.”

The study is the first of its kind to examine light hour’s influence on metabolism in mice, that are not considered seasonal animals as like humans they do not only breed in specific seasons. Animals breeding in specific seasons gain weight before the breeding season to save energy supplies.  

Light hours affect the metabolism

The researcher's inspiration for initiating the study stemmed from the significant variation in daylight hours across various regions of the world.

“We study the influence of the time-of-day on aspects of metabolism such as exercise, obesity and diabetes. However, most studies that investigate this link do so assuming an equal length of day and night all year round,” says Lewin Small.

Therefore, they wanted to find out what the seasonal light differences meant for the metabolism. Most people in the world live with at least a two-hour difference in light between summer and winter.

“I come from Australia, and when I first moved to Denmark, I was not used to the huge difference in light between summer and winter and I was interested in how this might affect both circadian rhythms and metabolism,” says Lewin Small and adds:

“Therefore, we exposed laboratory mice to different light hours representing different seasons and measured markers of metabolic health and the circadian rhythms of these animals.”

Because the research was conducted using mice as the experimental subjects, it is not possible to assume that the same thing goes for humans.

“This is a proof of principle. Do differences in light hours affect energy metabolism? Yes, it does. Further studies in humans may find that altering our exposure to artificial light at night or natural light exposure over the year could be used to improve our metabolic health,” says Juleen Zierath, Professor at the Novo Nordisk Center for Basic Metabolism Research (CBMR) and senior author of the study.

Lewin Small adds that the new knowledge is important to understand how eating patterns are affected by the light and seasons which might help us understand why some people gain more weight or if people gain more weight in a specific time of year.

“Differences in light between summer and winter could affect our hunger pathways and when we get hungry during the day,” he says.

Read the study ‘Seasonal light hours modulate peripheral clocks and energy metabolism in mice’ in Cell Metabolism

A visual circuit related to the habenula mediates the prevention of cocaine relapse by bright light treatment


Peer-Reviewed Publication

SCIENCE CHINA PRESS

A visual circuit related to the habenula mediates the prevention of cocaine relapse by bright light treatment 

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BRIGHT LIGHT TREATMENT ADMINISTERED DURING COCAINE WITHDRAWAL PREVENTS COCAINE-DRIVEN REINSTATEMENT AND ALLEVIATES AVERSIVE EMOTIONAL STATES THROUGH THE ACTIVATION OF THE VLGN/IGL-LHB PATHWAY

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CREDIT: ©SCIENCE CHINA PRESS




This study is led by Prof. Chaoran Ren (Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan university), Prof. Tifei Yuan (Shanghai Mental Health Center, Shanghai Jiaotong University School of Medicine), and Prof. Song Lin (Department of physiology, Jinan university)

The treatment of drug addiction remains a significant challenge, with cocaine use disorder (CUD) carrying a high rate of relapse and imposing a significant global burden. Over the past few decades, considerable efforts have been made to increase the effectiveness of extinction training, a method where individuals are repeatedly exposed to drug-related cues without actual drug use. These efforts have bolstered earlier reports that support the potential for interventions during drug withdrawal with extinction training to prevent relapse.

The lateral habenula (LHb) is particularly noteworthy as it is responsible for driving aversive emotional states, cognition, and withdrawal effects from cocaine. Previous studies have found that the LHb underlies the non-visual aspect of bright light treatment (BLT) in modulating aversive emotional states. Activation of the ventral lateral geniculate nucleus and intergeniculate leaflet (vLGN/IGL)-LHb pathway by BLT can modulate LHb neuronal excitability and fire mode switching. Considering that aversive emotional state is a significant driver of relapse, it is conceivable that light-based modulation of LHb neuronal activity could influence CUD-related symptoms, particularly relapse.

The present study investigated the effects and underlying circuit mechanisms of BLT during cocaine withdrawal with extinction training on relapse-related reinstatement. Yunwei Fu et al. began by mapping the brain network active during cocaine withdrawal using the neuronal activity marker c-Fos. They found a progressive potentiation of LHb neuronal activity during cocaine withdrawal. Subsequently, they found that BLT administrated during cocaine withdrawal ameliorates LHb neuronal activity, cocaine-driven reinstatement and the aversive emotional states.

To elucidate the neuronal circuitry underlying the effects of BLT on cocaine-driven reinstatement, the team focused on the vLGN/IGL-LHb pathway using various brain circuit analysis tools, including ex vivo electrophysiological recording, fiber photometry ,and chemogenetics. They revealed that the effects of BLT were mediated by activating LHb-projecting neurons in the vLGN/IGL or by inhibiting postsynaptic LHb neurons.

In summary, the team uncovered the non-visual function of light in modulating relapse-related reinstatement after cocaine withdrawal, with and without extinction training, offering a promising avenue for the use of light-based therapy in the treatment of drug addiction.