Physical activity and tailored support fails to deliver lasting benefits for smokers not ready to quit

Peer-Reviewed Publication

UNIVERSITY OF PLYMOUTH

Promoting physical activity and other behavioural support can help people wanting to reduce their smoking to quit in the short-term.

However, after nine months, physical activity delivers no noticeable benefits – compared with offering no additional support – in the rates of people stopping smoking, according to the findings of a major national study.

The Trial of physical Activity and Reduction of Smoking (TARS) study, led by the University of Plymouth with funding from the National Institute for Health and Care Research, took place across four cities – Plymouth, Nottingham, Oxford and London – before the COVID-19 pandemic.

Its aim was to provide a definitive answer as to whether future NHS services should be adapted to provide additional support to smokers not ready to quit but who do wish to reduce their smoking, with the hope of increasing sustained abstinence from smoking and associated health benefits.

The study also sought to look into previous suggestions that behavioural support for these smokers can lead to smoking reduction and more attempts to quit.

To answer these questions, half the 915 smokers recruited into the study were offered up to eight, weekly face-to-face or phone motivational support sessions to reduce their smoking and increase moderate to vigorous physical activity. It was an approach which had previously shown encouraging signs in a Plymouth pilot study, and was contrasted against the other half of participants who were offered the usual NHS advice on quitting.

The study showed that engaging with the motivational support had some short-term benefits, with 19% of those receiving the additional support saying they had at least halved the number of cigarettes smoked by three months – 14% had still halved their smoking after nine months. By contrast, around 10% of those receiving the standard advice reported having halved their cigarette intake at both milestones.

However, just 2% of those who received the additional support had abstained from smoking between three and nine months. Less than 1% of those receiving the standard advice managed to abstain from smoking for those six months.

In addition, while after three months people receiving the additional support took part in 81 minutes more physical activity each week than those receiving no support, researchers did not find evidence of sustained differences in physical activity at nine months.

With the additional support costing health services in the region of £240 per person, the study’s authors say their findings show the approach is neither effective for long-term smoking cessation or cost-effective.

The research, published in the journal Addiction, also involved the University Hospitals Plymouth NHS Trust, St George’s University of London, University of Oxford, University of Nottingham, University of Exeter, and Plymouth City Council.

Adrian Taylor, Professor in Health Services Research within the University of Plymouth’s Peninsula Medical School, is the study’s lead author. He said: “Generally, the smokers in our study were enthusiastic about the support they received to help reduce their smoking and increase physical activity, which avoided pressuring them to quit. However, they were unable to maintain increases in physical activity and smoking reduction did not lead to more smokers giving up completely, which is the best thing for an individual’s health. Helping smokers to move from wanting to reduce to quitting completely is far more challenging than other less rigorous studies had suggested.”

“This is a further demonstration of the scale of the challenge facing society if we are to achieve the UK Government’s stated aim of being smoke free by 2030. However, it is potentially only through additional difficult national policy decisions such as even higher taxation on tobacco, the subsidised promotion of vaping, and increasing the legal age of tobacco purchasing, in line with other countries such as New Zealand, that the huge costs of smoking for our NHS Services will be reduced.”

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JOURNAL

Addiction

DOI

10.1111/add.16129 

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Effectiveness and cost-effectiveness of behavioural support for prolonged abstinence for smokers wishing to reduce but not quit: Randomised controlled trial of physical activity assisted reduction of smoking (TARS)

ARTICLE PUBLICATION DATE

6-Mar-2023

Potential treatment of autoimmune diseases revealed in new study

Scientists have uncovered a chemical compound that holds potential as a therapeutical for various autoimmune diseases, and they’ve used it to treat mice.

Peer-Reviewed Publication

OKINAWA INSTITUTE OF SCIENCE AND TECHNOLOGY (OIST) GRADUATE UNIVERSITY

 

IMAGE: MICE THAT HAVE NEUROINFLAMMATION CAUSED BY AUTOIMMUNITY WERE TREATED WITH PEP. THE RESULTS FOUND THAT PEP-TREATED MICE SHOWED IMPROVED SIGNS OF RECOVERY, IN COMPARISON TO MICE THAT WEREN’T TREATED WITH PEP. view more 

CREDIT: TSUNG-YEN HUANG (OIST)

Scientists in Japan have revealed a chemical compound that could be used for the treatment of various autoimmune diseases like multiple sclerosis and rheumatoid arthritis. These diseases occur when the body’s immune response goes wiry. The immune system, which normally attacks pathogens and infections, instead attacks healthy cells and tissues. For the millions of people who suffer from autoimmune diseases worldwide, the result can be debilitating—rheumatoid arthritis causes excessive joint pain, while multiple sclerosis can disable one’s brain and spinal cord function.

“The key to the development of autoimmune diseases, and thus the way to inhibit this development, lies in our cells, but the underlying mechanism has always been unclear,” stated Prof. Hiroki Ishikawa, who leads the Immune Signal Unit at the Okinawa Institute of Science and Technology (OIST). “Now, our recent research has shed light on a compound that could suppress the development of these diseases.”

Prof. Ishikawa went on to explain that this research, published in Cell Reports, could lead to the development of treatments for autoimmune diseases.

The research focused on T helper 17 cells, or Th17 cells. Th17 cells are a type of T cell—a group of cells, which form major parts of the immune system. These cells, which exist in high numbers in our guts, evolved to help us fight invasive pathogens but, sometimes, they’re overactivated and mistake normal, healthy tissue as pathogens, resulting in autoimmunity. The generation of Th17 cells requires glycolysis, a metabolic process in which glucose is broken down and converted to energy to support the metabolic needs of cells. Glycolysis is essential for the growth of not only Th17 cells but also a variety of cells in our body.

“What’s interesting in that excessive glycolysis seems to suppress Th17 cell activity,” stated first author, Mr. Tsung-Yen Huang, a PhD candidate in the Immune Signal Unit. “So, we hypothesized that molecules produced during glycolysis may inhibit the cells.”

Enter phosphoenolpyruvate, or PEP for short. This chemical compound is a metabolite produced when glucose is converted to energy. Since it is part of such an important process, PEP is generated every day in our bodies. The researchers found that treatment with PEP can inhibit the maturation of TH17 cells, leading to resolution of inflammatory response.

Mr. Huang explained how this was, at first, a confusing result, as it went against all other research on the topic, but he decided to persevere and take a closer look at what could be occurring.

The research led them to a protein called JunB, which is essential for the maturation of Th17 cells. JunB promotes Th17 maturation by binding to a set of specific genes. The researchers found that PEP treatment inhibits the generation of Th17 cells by blocking JunB activity.

Armed with this knowledge, the researchers went on to treat mice that had neuroinflammation caused by autoimmunity with PEP. This disease is very similar to multiple sclerosis and these mice showed positive signs of recovery. The scientists have now filed a patent to continue with this research.

“Our results show the clinical potential of PEP,” explained Mr. Huang. “But first we need to increase its efficiency.”

In the past, researchers who were interested in developing a treatment for autoimmune diseases, often looked at inhibiting glycolysis and thus Th17 cells. But glycolysis is essential to various types of cells in the body and inhibiting it could have significant side-effects. PEP has the potential to be used as a treatment without resulting in such side-effects.

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JOURNAL

Cell Reports

DOI

10.1016/j.celrep.2023.112205 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Phosphoenolpyruvate regulates the Th17 transcriptional program and inhibits autoimmunity

ARTICLE PUBLICATION DATE

28-Mar-2023

Humanity’s quest to discover the origins of life in the universe

Reports and Proceedings

ETH ZURICH

 

IMAGE: DIDIER QUELOZ, NOBEL LAUREATE, PROFESSOR OF ASTROPHYSICS, DIRECTOR OF ETH ZURICH'S CENTRE FOR ORIGIN AND PREVALENCE OF LIFE, AND DIRECTOR OF THE UNIVERSITY OF CAMBRIDGE'S LEVERHULME CENTRE FOR LIFE IN THE UNIVERSE. view more 

CREDIT: ETH ZURICH / MARCO ROSASCO PHOTOGRAPHY

“We are living in an extraordinary moment in history,” says Didier Queloz, who directs ETH Zurich’s Centre for Origin and Prevalence of Life and the Leverhulme Centre for Life in the Universe at Cambridge. While still a doctoral student Queloz was the first to discover an exoplanet - a planet orbiting a solar-type star outside of Earth’s solar system. A discovery for which he would later receive a Nobel Prize in physics. Within a generation, scientists have now discovered more than 5,000 exoplanets and predict the potential existence of trillions more in the Milky Way galaxy alone. Each discovery inspires more questions than answers about how and why life emerged on Earth and whether it exists elsewhere in the universe. Technological advancements, such as the James Webb Space Telescope and interplanetary missions to Mars, accelerate access to an overwhelming volume of new observations and data, such that it will take the convergence of a multidisciplinary network to understand the emergence of life in the universe.

ETH Zurich, Cambridge, Harvard, and Chicago found the “Origins Federation”

Joining forces with chemist and fellow Nobel Laureate, Jack Szostak and astronomer, Dimitar Sasselov, Didier Queloz announced the founding of a new “Origins Federation” during the American Association for the Advancement of Science (AAAS). While a fictional interstellar federation might immediately spring to mind, this international alliance brings together the expertise of researchers working in the origins of life centers and initiatives at ETH Zurich, University of Cambridge, Harvard University, and The University of Chicago.

Together, scientists will explore the chemical and physical processes of living organisms and environmental conditions hospitable to supporting life on other planets. “The Origins Federation,” Queloz commented, “builds upon a long-standing collegial relationship strengthened through a shared collaboration in a recently completed project with the Simons Foundation.”

What humanity could learn from extra-terrestrial biosignatures

Such collaborations support the work of researchers like Zoology professor, Emily Mitchell. Mitchell, who works with Queloz in Cambridge’s Leverhulme Centre for Life in the Universe is an ecological time traveler. She uses field-based laser-scanning and statistical mathematical ecology on 580-million-year-old fossils of deep-sea organisms to determine the driving factors that influence the macro-evolutionary patterns of life on Earth. Speaking during ETH Zurich’s Origins of Life session at the AAAS, Mitchell took participants back in time to 4-billion years ago when Earth’s early atmosphere - devoid of oxygen and steeped in methane – showed its first signs of microbial life. She spoke about how life survives in extreme environments and then evolves offering potential Astro-biological insights into the origins of life elsewhere in the universe.

“As we begin to investigate other planets, through the Mars missions,” Mitchell says, “biosignatures could reveal whether or not the origin of life itself and its evolution on Earth is just a happy accident or part of the fundamental nature of the universe, with all its biological and ecological complexities.”

Colonizing space with synthetic cells

While complex biological cells are not yet fully understood, synthetic cells allow biochemists, like Kate Adamala, University of Minnesota’s Protobiology Lab to deconstruct complex systems into simpler parts. Parts that allow scientists to understand the basic principles of life and evolution not only on Earth, but potentially life on other planets in the solar system.

Adamala launched her quest to build life from scratch as a graduate student at Harvard working with Nobel Laureate, Jack Szostak. She endeavors to create simple, cell-like bioreactors resembling the earliest forms of life by applying the principles of engineering to biology. During the AAAS, Adamala explained how synthetic cells allow scientists to study the past, present, and future of life in the universe. Unlike biological cells, it is possible to digitalize synthetic cells and transmit them across vast distances to create, for example, on demand medication or vaccines – an “Astro-pharmacy” that could potentially support life on spaceship, or even a future Martian colony. Until such time, synthetic cells offer practical applications for humanity in terms of sustainable energy systems, higher crop yields, and biomedical therapies.

What is life?

While there is not yet a comprehensive definition of life, the quest to discover its origins has inspired enthusiasm, new collaborations, and opened the doors within the scientific community’s most hallowed halls.

 

Special thanks to Carl Zimmer, a columnist for The New York Times and author of “Life’s Edge: The search for what it means to be alive” for moderating ETH Zurich’s Origins of Life discussion during the AAAS.

###

 

Public Announcement

Embargoed until March 4th, 2023, 1 PM ET / 6 PM GMT / 19hrs CET

Origins Federation

Researchers from four leading institutions are pleased to announce their intent to create a research consortium with the goal of facilitating efficient multidisciplinary and innovative collaborative research to advance our understanding of the emergence and early evolution of life, and its place in the cosmos.

The following centers establish the Origins Federation:

• The Origins of Life Initiative (Harvard University),
• Centre for Origin and Prevalence of Life (ETH Zurich),
• Center for the Origins of Life (The University of Chicago),
• Leverhulme Centre for Life in the Universe (University of Cambridge).

The Origins Federation will pursue scientific research topics of interest to its founding centers with a long-term perspective and common milestones. It will strive to establish a stable funding platform to create opportunities for creative and innovative ideas, and to enable young scientists to make a career in this new field.

The Origins Federation is open to new members, both centers and individuals, and is committed to developing the mechanisms and structure to achieve that aim.

The Origins Federation inaugural science conference will take place at Harvard University on September 12 – 15, 2023.

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ARTICLE TITLE

Humanity’s quest to discover the origins of life in the universe

ARTICLE PUBLICATION DATE

4-Mar-2023

New breakthrough enables perfectly secure digital communications

Reports and Proceedings

UNIVERSITY OF OXFORD

• Researchers have achieved a breakthrough to enable ‘perfectly secure’ hidden communications for the first time.
• The method uses new advances in information theory methods to conceal one piece of content inside another in a way that cannot be detected.
• This may have strong implications for information security, besides further applications in data compression and storage.

A group of researchers has achieved a breakthrough in secure communications by developing an algorithm that conceals sensitive information so effectively that it is impossible to detect that anything has been hidden.

The team, led by the University of Oxford in close collaboration with Carnegie Mellon University, envisage that this method may soon be used widely in digital human communications, including social media and private messaging. In particular, the ability to send perfectly secure information may empower vulnerable groups, such as dissidents, investigative journalists, and humanitarian aid workers.

The algorithm applies to a setting called steganography: the practice of hiding sensitive information inside of innocuous content. Steganography differs from cryptography because the sensitive information is concealed in such a way that this obscures the fact that something has been hidden. An example could be hiding a Shakespeare poem inside an AI-generated image of a cat.

Despite having been studied for more than 25 years, existing steganography approaches generally have imperfect security, meaning that individuals who use these methods risk being detected. This is because previous steganography algorithms would subtly change the distribution of the innocuous content.

To overcome this, the research team used recent breakthroughs in information theory, specifically minimum entropy coupling, which allows one to join two distributions of data together such that their mutual information is maximised, but the individual distributions are preserved.

As a result, with the new algorithm, there is no statistical difference between the distribution of the innocuous content and the distribution of content that encodes sensitive information.

The algorithm was tested using several types of models that produce auto-generated content, such as GPT-2, an open-source language model, and WAVE-RNN, a text-to-speech converter. Besides being perfectly secure, the new algorithm showed up to 40% higher encoding efficiency than previous steganography methods across a variety of applications, enabling more information to be concealed within a given amount of data. This may make steganography an attractive method even if perfect security is not required, due to the benefits for data compression and storage.

The research team has filed a patent for the algorithm, but intend to issue it under a free licence to third parties for non-commercial responsible use. This includes academic and humanitarian use, and trusted third-party security audits. The researchers have published this work as a preprint paper on arXiv, as well as open-sourced an inefficient implementation of their method on Github. They will also present the new algorithm at the premier AI conference, the 2023 International Conference on Learning Representations in May.

AI-generated content is increasingly used in ordinary human communications, fuelled by products such as ChatGPT, Snapchat AI-stickers, and TikTok video filters. As a result, steganography may become more widespread as the mere presence of AI-generated content will cease to arouse suspicion.

Co-lead author Dr Christian Schroeder de Witt (Department of Engineering Science, University of Oxford) said: ‘Our method can be applied to any software that automatically generates content, for instance probabilistic video filters, or meme generators. This could be very valuable, for instance, for journalists and aid workers in countries where the act of encryption is illegal. However, users still need to exercise precaution as any encryption technique may be vulnerable to side-channel attacks such as detecting a steganography app on the user’s phone.’

Co-lead author Samuel Sokota (Machine Learning Department, Carnegie Mellon University) said: ‘The main contribution of the work is showing a deep connection between a problem called minimum entropy coupling and perfectly secure steganography. By leveraging this connection, we introduce a new family of steganography algorithms that have perfect security guarantees.’

Contributing author Professor Jakob Foerster (Department of Engineering Science, University of Oxford) said: ‘This paper is a great example of research into the foundations of machine learning that leads to breakthrough discoveries for crucial application areas. It's wonderful to see that Oxford, and our young lab in particular, is at the forefront of it all.’

Besides Dr Christian Schroeder de Witt, Samuel Sokota  and Professor Jakob Foerster, the study involved Prof. Zico Kolter at Carnegie Mellon University, USA, and Dr Martin Strohmeier from armasuisse Science+Technology, Switzerland. The work was partially funded by a EPSRC IAA Doctoral Impact fund hosted by Professor Philip Torr, Torr Vision Group, at the University of Oxford.

DOI

10.48550/arXiv.2210.14889 

The planet that could end life on Earth

Experiment demonstrates solar system’s fragility

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - RIVERSIDE

 

IMAGE: SOLAR SYSTEM MONTAGE OF THE NINE PLANETS AND MOONS OF JUPITER IN OUR SOLAR SYSTEM. view more 

CREDIT: NASA/JPL/ASU

A terrestrial planet hovering between Mars and Jupiter would be able to push Earth out of the solar system and wipe out life on this planet, according to a UC Riverside experiment.

UCR astrophysicist Stephen Kane explained that his experiment was meant to address two notable gaps in planetary science. 

The first is the gap in our solar system between the size of terrestrial and giant gas planets. The largest terrestrial planet is Earth, and the smallest gas giant is Neptune, which is four times wider and 17 times more massive than Earth. There is nothing in between. 

“In other star systems there are many planets with masses in that gap. We call them super-Earths,” Kane said. 

The other gap is in location, relative to the sun, between Mars and Jupiter. “Planetary scientists often wish there was something in between those two planets. It seems like wasted real estate,” he said. 

These gaps could offer important insights into the architecture of our solar system, and into Earth’s evolution. To fill them in, Kane ran dynamic computer simulations of a planet between Mars and Jupiter with a range of different masses, and then observed the effects on the orbits of all other planets. 

The results, published in the Planetary Science Journal, were mostly disastrous for the solar system. “This fictional planet gives a nudge to Jupiter that is just enough to destabilize everything else,” Kane said. “Despite many astronomers having wished for this extra planet, it’s a good thing we don’t have it.”

Jupiter is much larger than all the other planets combined; its mass is 318 times that of Earth, so its gravitational influence is profound. If a super-Earth in our solar system, a passing star, or any other celestial object disturbed Jupiter even slightly, all other planets would be profoundly affected.

Depending on the mass and exact location of a super-Earth, its presence could ultimately eject Mercury and Venus as well as Earth from the solar system. It could also destabilize the orbits of Uranus and Neptune, tossing them into outer space as well. 

The super-Earth would change the shape of this Earth’s orbit, making it far less habitable than it is today, if not ending life entirely.

If Kane made the planet’s mass smaller and put it directly in between Mars and Jupiter, he saw it was possible for the planet to remain stable for a long period of time. But small moves in any direction and, “things would go poorly,” he said. 

The study has implications for the ability of planets in other solar systems to host life. Though Jupiter-like planets, gas giants far from their stars, are only found in about 10% of the time, their presence could decide whether neighboring Earths or super-Earths have stable orbits. 

These results gave Kane a renewed respect for the delicate order that holds the planets together around the sun. “Our solar system is more finely tuned than I appreciated before. It all works like intricate clock gears. Throw more gears into the mix and it all breaks,” Kane said. 

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JOURNAL

The Planetary Science Journal

DOI

10.3847/PSJ/acbb6b 

METHOD OF RESEARCH

Computational simulation/modeling

ARTICLE TITLE

The Dynamical Consequences of a Super-Earth in the Solar System

Multiple crises, better health for older people, and the ocean and its biodiversity: G7 science academies present statements for the G7 Summit in Hiroshima

Reports and Proceedings

LEOPOLDINA

How can we manage multiple crises such as pandemics, wars and the effects of climate change, which occur at the same time and reinforce each other? How can we protect the ocean and its biodiversity and how can science and innovation contribute to improving older people’s health? The science academies of the G7 states have published three statements regarding these questions today. Illustrating possible courses of action, the academies appeal to the G7 governments to address these issues at this year’s G7 Summit in Hiroshima, Japan, in May. The statements were prepared under the leadership of the Science Council of Japan with the participation of the German National Academy of Sciences Leopoldina.

“The governments of the G7 states are meeting this year against a backdrop of multiple crises that are interdependent and need to be tackled together: climate change, war and the impact of the pandemic. The preservation of marine biodiversity and an ageing society also require solutions that need to be developed through multilateral cooperation and on the basis of robust research results. For this purpose, the G7 science academies – the S7 Academies – are presenting their science-based recommendations in the run up to the summit,” says Professor (ETHZ) Dr Gerald Haug, President of the German National Academy of Sciences Leopoldina.

Multiple crises

In their statements, the G7 science academies identify three major current challenges: the consequences of anthropogenic (human-made) climate change, the socioeconomic impact and health implications of the COVID-19 pandemic, and Russia’s war of aggression against Ukraine. These three converging and mutually reinforcing crises highlight the urgent need for action. With regard to climate change, there are currently significant shortfalls in meeting the Paris climate goals: both in terms of the pledges to mitigate climate change and in terms of delivering the necessary reductions in greenhouse gas emissions. The statements explain that rapid and decisive action is needed to address multiple crises and to advance the development of more resilient societies.

Ageing societies

The proportion of the world’s population aged 65 or above is expected to increase from 10% to 16% by 2050. Entering this major demographic transition, there is a need to achieve a society in which an increasing number of people can enjoy health, well-being, and independence throughout their lifespans to the fullest extent.  While it has been well established that maintaining an appropriate environment, physical activity, and social interactions is beneficial in reducing the likelihood of developing age-related diseases, our understanding of the underlying biological mechanisms is still insufficient to develop effective and personalized prevention strategies. This is one of the reasons, according to the S7 Academies, that more investment is needed to promote aging science or “Geroscience”.

The ocean and its biodiversity

The ocean is a global, interconnected body of saltwater and covers approximately 70% of the Earth’s surface. The ocean’s biodiversity consists of complex systems. Researching their mechanisms, including the long-term perspective of evolution, is crucial to understanding the effects of human intervention in the marine ecosystem and its biodiversity. It is therefore crucial to foster joint, long-term efforts, for example expanding international databases and observation networks as well as training suitable experts.

The joint statements of the G7 science academies are available here in English: www.leopoldina.org/g7-2023

The science academies accompany the annual summits of the G7 states. In the run up to the summit, they address science-related issues that are relevant to the agenda and require multilateral action. The G7 Summit is scheduled for 19 to 21 May 2023 in Hiroshima, Japan. Information about the G7 process and advice provided by the science academies as well as the current statements is available here: https://www.leopoldina.org/en/international/g7-and-g20-policy-advice/.

The Leopoldina on Twitter: www.twitter.com/leopoldina

Most relevant hashtags are #S7, #Science7, #GScience2023

About the German National Academy of Sciences Leopoldina

As the German National Academy of Sciences, the Leopoldina provides independent science-based policy advice on matters relevant to society. To this end, the Academy develops interdisciplinary statements based on scientific findings. In these publications, options for action are outlined; making decisions, however, is the responsibility of democratically legitimized politicians. The experts who prepare the statements work in a voluntary and unbiased manner. The Leopoldina represents the German scientific community in the international academy dialogue. This includes advising the annual summits of heads of state and government of the G7 and G20 countries. With 1,600 members from more than 30 countries, the Leopoldina combines expertise from almost all research areas. Founded in 1652, it was appointed the National Academy of Sciences of Germany in 2008. The Leopoldina is committed to the common good.

Females of all ages, ethnicities have more salt- sensitive hypertension than males

Peer-Reviewed Publication

MEDICAL COLLEGE OF GEORGIA AT AUGUSTA UNIVERSITY

 

IMAGE: (FROM LEFT) JESSICA FAULKNER, PHD, GRADUATE STUDENT CANDEE BARRIS (SEATED) AND ERIC BELIN DE CHANTEMELE, PHD view more 

CREDIT: TAKEN BY AU PHOTOGRAPHER MICHAEL HOLAHAN.

There is increasing evidence that females of all ethnicities and ages are more salt sensitive than males, and that this propensity to hold onto more salt, which drives blood pressure up, increases after menopause.

Another important emerging bottom line is that healthy blood pressures might differ between the sexes, which means females might benefit from earlier and different intervention to avoid damage to their heart and vasculature.

“The realities are that women and men regulate our blood pressure differently and our blood pressures are different at baseline,” says Dr. Eric Belin de Chantemele, physiologist in the Vascular Biology Center at the Medical College of Georgia at Augusta University.

It’s generally thought that females are better protected against cardiovascular disease than males until menopause, when the risk is thought to level out. Laboratory studies in traditional hypertension rat models, like the Dahl Salt-Sensitive rat, have generally supported those ideas, including an equalization of risk in the two sexes following removal of the ovaries.

But in female humans and some mouse models the protection appears less absolute: Because more females are salt sensitive before menopause, and menopause exacerbates both its severity and prevalence, MCG scientists report in a review article featured on the cover of the American Heart Association journal Hypertension.

That supports yet another emerging concept that the sex chromosome XX predisposes females to salt sensitivity, presumably because females need to nearly double their fluid volume during pregnancy, and estrogen does help mitigate some of the related increased risk, at least until its levels drop after menopause, says Belin de Chantemele.

Work primarily in male humans and animal models feeds the misconception that women are less salt sensitive, Belin de Chantemele and his colleagues Dr. Jessica Faulkner, vascular physiologist in the MCG Department of Physiology and AU Graduate Student Candee T. Barris write.

“Salt sensitivity is one of the leading factors for hypertension. And, if you look at people who have treatment-resistant hypertension, which is most people, most are salt sensitive,” Belin de Chantemele says. “It’s very important to know the cause of that.”

Salt sensitivity means your body has an apparent natural tendency to hold onto salt rather than excrete excess in the urine. Salt sensitivity of blood pressure is when blood pressure decreases or increases more than 10% in response to how much salt you are consuming, the scientists say. 

Salt sensitivity is a factor in about half of cases where the cause of hypertension is not obvious, like a kidney problem. It’s also a usual contributor to treatment resistant hypertension, and only about 1 in 4 adults have their hypertension under control, according to the Centers for Disease Control and Prevention.

There also is good human information that reducing salt intake reduces salt sensitivity and even more so in females, Belin de Chantemele says.

“We think it’s mostly the vasculature not relaxing in response to an intake of sodium that is leading to an elevation in pressure,” he says of the distinctive female handling of salt. Animal studies of salt sensitivity generally indicate that the kidneys, which should excrete more sodium when we consume too much, are working fine in females. In fact, human and lab animal evidence indicates that female kidneys are better at salt excretion, he says. The problem, it appears, is with the vasculature, because salt should also make the blood vessels relax.

“If you expand your blood vessels more then you will be able to keep your blood pressure stable, but if your vessels do not relax, that is how pressure goes up,” Belin de Chantemele says. “Later on, you also excrete sodium to reduce your blood volume, but the first response should be relaxation of your blood vessels.” And that is the way it works in those of us who are salt resistant. But apparently not so well in many females.

One of the other unique factors about females Belin de Chantemele and others are finding that appears important is that, also likely because their bodies are prepared to reproduce, they have high levels of the hormone aldosterone. Aldosterone is produced by the adrenal gland and has a direct effect on blood pressure by regulating salt-water balance in the body. Females also tend to have way more receptors for aldosterone, called mineralocorticoid receptors.

High levels of aldosterone are known to contribute to bad things for the body like widespread inflammation, stiff and scarred blood vessels, even enlargement of the heart. In females the scientists think and have some evidence that aldosterone is mostly deleterious to blood vessels, including their important ability to dilate to accommodate more blood volume in response to holding onto more salt. The scientists see this effect in their lab mice and in women.

“We think that what is happening is that salt-sensitive females cannot reduce their aldosterone production enough and we think that predisposes them to salt sensitivity,” Belin de Chantemele says.

Higher activation of the epithelial sodium channel, which prompts the body to hold onto more salt, is another negative for females. And, the renin-angiotensin-aldosterone system, which coordinates the work of the heart, blood vessels and kidneys, to regulate fluid and electrolyte balance in the body, also tends to be suppressed in females.

There are drugs that target aldosterone, including the old blood pressure medication spironolactone, as well as newer drugs like eplerenone and finerenone, which Belin de Chantemele has studied in the lab and which he has been advocating would be a good first-line treatment for females because they lower aldosterone action. He notes the drugs are getting better traction recently.

One of the MCG scientists’ many active pursuits is looking at whether aldosterone and estrogen levels have a connection, but they don’t have evidence of one at this point.  

Important to the mix of better understanding sex differences in how males and females regulate blood pressure is the also emerging reality that, while female blood pressures tend to run lower than males, that doesn’t necessarily mean their pressures are good. Because while current guidelines have the same healthy blood pressure range for both sexes, it appears that females experience damage at a lower threshold or pressure.

Women tend to start with a lower pressure so it’s presumed they are not hypertensive but, particularly after menopause, the increases in pressure can be much larger for females, Belin de Chantemele says.

“I would say that the threshold for hypertension should be lower in women,” he says. “If we had a different threshold, we would notice changes in pressure faster, so we could hopefully intervene faster.” And when blood pressures start to rise, treatment for women should likely start at a lower pressure, he says.

While salt sensitivity is prevalent in both sexes and different ethnicities, large population studies worldwide indicate it’s most prevalent in females. For example, large studies in China indicate females have the biggest blood pressure response — up and down — to changes in salt levels in the diet. Big studies in individuals from the United States, France, Spain and Mexico, also indicate salt sensitivity is significantly more prevalent in females. They note that people of African American decent have the higher overall incidence regardless of their sex at 70%.

The two sex chromosomes, the XX that make a female and the XY that means male, as well as sex hormones like estrogen, likely are key to females’ propensity for this common condition. Genetics, like variations in the estrogen receptor, likely also contribute.

Evidence also indicates that females tend to like salt more than males, Belin de Chantemele says. Like many sex-related differences, the proclivity for salt likely relates to the physiological need to retain sodium, and the fluid which follows sodium, which is sufficient to sustain another life in pregnancy. There also is some evidence that the male hormone testosterone suppresses the appetite for salt.

Mice models that have been found to spontaneously develop salt-sensitive hypertension might be better for future studies of this condition in females than older models like the Dahl-Salt Sensitive rat, they write. Because what many have shown over and over in rats does not reproduce what is happening with females, Belin de Chantemele says.

He also suggests that all of us back off the salt intake. “There is nothing better than that,” he notes.

Read the full study.

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JOURNAL

Hypertension

ARTICLE TITLE

Salt Sensitivity of Blood Pressure in Women

Wings, not webs: Certain bugs are the winners of urbanization, impacting cities’ insect diversity

Scientists studying how urbanization impacts insects found that some bugs are better adapted to urban environments than others

Peer-Reviewed Publication

FRONTIERS

 

IMAGE: A ‘CUCUMBER GREEN SPIDER’ view more 

CREDIT: DR MARION CHATELAIN

Cities are bursting with life, both human and animal. The smallest of them, insects, spiders, and ants are easily overseen, but their presence – or absence – in cities has wide-reaching effects. Scientists in Austria have published a study in Frontiers in Ecology and Evolution, which found a correlation between the presence of arthropods – invertebrate animals with an exoskeleton; among them are bees, insects, and spiders – and level of urbanization.

“We show that richness and diversity of arthropods on trees and bushes decreases along the rural-urban gradient,” said first author Dr Marion Chatelain, a postdoctoral researcher at the University of Innsbruck, Austria. “More specifically, we show that urbanization disfavors wingless groups, particularly so on trees. Indeed, web spiders and springtails are less likely to be found in the city, where, on the contrary, aphids, woodlice and flies are common.”

From bush to treetop

“In this study, we compared how different indexes of urbanization shape arthropod communities,” explained Chatelain. To do so, they collected arthropod samples at 180 sites within an area covering 56.5 sq km in and around the Austrian city of Innsbruck.

At each site, samples were collected in three micro-habitats: the canopy, the tree bark, and the bush layer. By measuring the percentage of paved-over and built-up area, vegetation or trees, Chatelain and her colleagues estimated the level of urbanization within 100 meters, 500 meters and 1000 meters around each site. Then they tested the impact it had on the total number of arthropods (abundance), how many different taxonomic groups were present (richness), and what arthropods were present. The team also considered diversity, a metric taking both abundance and richness into account. Measuring the level of urbanization at different scales allowed to better explain the effects of urbanization on arthropod communities.

Urbanization bugs unwinged, carnivorous, web-building arthropods

Their findings showed a correlation between the level of urbanization and total arthropod numbers in the bush layer. The more urbanized the site was, the more bark lice and crab spiders dwelled on the shrubs – a pattern that may be due to more nutritious leaves in the bush layer in cities. In the canopy, certain species, like flies, increased in more urbanized areas, whereas certain groups of spiders were found less often. This may indicate an advantage of winged arthropods in cities, likely because of their increased ability to move between isolated green spaces.  

Chatelain and her team also observed type-specific effects on bugs. For example, they found web-building spiders at consistently lower density than those that actively hunt, such as crab spiders. This suggests that the decline or increase of spider groups correlates with their hunting modes. The lower occurrence of four out of ten spider families examined in the study, suggests a direct impact on plant-eating bugs, which were found more often in urban settings.

Certain arthropod groups do well in cities while other don’t, the scientists said. This, however, offers no direct conclusion on total bug numbers: “Because some groups thrive while other are filtered from urban areas, there are at least as many arthropods in the city as in the rural surrounding,” Chatelain stated. “In fact, in bushes, arthropods, especially bark lice and crab spiders, are actually more abundant in the city.”

From bugs to birds

The researchers also pointed out possible bottom-up effects on insect-eating birds. “Our results suggest that urbanization affects the availability of arthropod prey, which is expected to have consequences on predator nutritional status, foraging behavior, reproduction success, survival and distribution within the urban landscape,” Chatelain said. “This study is part of a larger project aiming at understanding the effects of urbanization on food availability, diet and nutritional status of great tits and blue tits.”

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JOURNAL

Frontiers in Ecology and Evolution

DOI

10.3389/fevo.2023.980387 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Urban-driven decrease in arthropod richness and diversity associated with group-specific changes in arthropod abundance

ARTICLE PUBLICATION DATE

7-Mar-2023