Publisher Health

Running may be a useful activity to undertake for better mental health. University of Tsukuba researchers have found that only ten minutes of moderate-intensity running increases local blood flow to the various loci in the bilateral prefrontal cortex — the part of the brain that plays an important role in controlling mood and executive functions. These findings may contribute to the development of a wider range of treatment recommendations to benefit mental health.
There’s clear evidence that physical activity has many benefits, such as the ability to improve mood, but in previous studies, cycling was often the form of exercise studied. Running, however, has always played an important role in the well-being of humans. The unique form and efficiency of human running, which includes the ability to sustain this form of exertion (i.e., by jogging as opposed to sprinting), and the evolutionary success of humans are closely linked.
Despite this fact, researchers had not yet looked closely at the effects of running on brain regions that control mood and executive functions. “Given the extent of executive control required in coordinating balance, movement, and propulsion during running, it is logical that there would be increased neuronal activation in the prefrontal cortex and that other functions in this region would benefit from this increase in brain resources,” explains Professor Hideaki Soya.
To test their hypothesis, the research team used the well-established Stroop Color-Word Test and captured data on hemodynamic changes associated with brain activity while participants were engaged in each task. For example, in one task, incongruent information is shown, i.e., the word red is written in green, and the participant must name the color rather than read out the word. To do so, the brain must process both sets of information and inhibit the extraneous information. The Stroop interference effect was quantified by the difference in response times for this task and those for a simpler version of the task — stating the names of color swatches.
The results demonstrated that, after ten minutes of moderate-intensity running, there was a significant reduction in Stroop interference effect time. Furthermore, bilateral prefrontal activation had significantly increased during the Stroop task. After running, participants reported being in a better mood. “This was supported by findings of coincident activations in the prefrontal cortical regions involved in mood regulation,” first author Chorphaka Damrongthai adds.
Given that many characteristics of the human prefrontal cortex are uniquely human, this study not only sheds light on the present benefits of running but also on the possible role that these benefits may have played in the evolutionary past of humans.
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Free from the sun, vitamin D delivers a natural source for one of the hormones essential to our bodies, especially the bones. But when you’re down on this essential nutrient, it’s not only your bones that could suffer, but also your cardio health, according to new research from the University of South Australia.
In the first study of its kind, researchers from the UniSA’s Australian Centre for Precision Health at SAHMRI have identified genetic evidence for a role of vitamin D deficiency in causing cardiovascular disease.
The study, which is published in European Heart Journal today, shows that people with vitamin D deficiency are more likely to suffer from heart disease and higher blood pressure, than those with normal levels of vitamin D*. For participants with the lowest concentrations the risk of heart disease was more than double that seen for those with sufficient concentrations.
Globally, cardiovascular diseases (CVDs) are the leading cause of death worldwide, taking an estimated 17.9 million lives per year. In Australia, CVD accounts for one in four deaths and costs the Australian economy five billion dollars each year, more than any other disease.
Low concentrations of vitamin D are common in many parts of the world, with data from the UK Biobank showing that 55 per cent of participants have low levels of vitamin D (

The latest findings of a series of studies on mice that examined harmful effects caused by spending time in space show that gene expression related to liver metabolism is altered in response to the space environment. The benefit of these findings is that it may be possible to offset these changes with dietary supplementation during spaceflight.
Like other inhabitants of this planet, humans have evolved for life on Earth, not life in space or elsewhere. During spaceflight, the human body is exposed to a harmful environment, characterized by null or microgravity and high radiation levels. The liver is affected by spaceflight more than any other organ — its crucial role in neutralizing harmful substances in the body means that spaceflight places incredible demands on the organ.
“Environmental stressors, such as high radiation and microgravity, induce a state of oxidative stress,” explains Professor Iwao Ohtsu. “To deal with reactive oxygen and nitrogen compounds, the liver uses its limited resources, that is, antioxidant sulfur-containing compounds.” The research team conducted novel experiments to compare liver gene expression levels between mice exposed to microgravity, mice exposed to simulated gravity on the International Space Station, and mice at ground level on Earth.
Mice that traveled to space and back had a lower antioxidant capacity because they had lower levels of the sulfur-containing compounds (e.g., ergothioneine, cysteine, and glutathione) that play a role in protecting cells by reducing reactive oxygen compounds, which limits free-radical damage. Overall, many indicators of oxidative stress were evident in the livers of these mice. In addition, there was greater expression of genes related to oxidative stress and sulfur metabolism pathways (which deplete levels of sulfur-containing antioxidant compounds) in mice that had been exposed to space.
Some effects, however, only occurred in mice exposed to microgravity. “Consequently, we were able to identify that some aspects of altered liver metabolism are counteracted by exposure to artificial gravity, whereas those caused by other environmental effects could be treated with alternative solutions, such as the addition of dietary supplements to astronauts’ diets,” says Professor Ohtsu.
This research not only identifies factors that could exacerbate the likelihood of liver damage but, by clarifying the role of specific metabolic pathways, also demonstrates the potential for existing drugs or dietary supplements to be used to treat or prevent such damage as humans embark on a new era of space exploration.
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Good glucose control is important for reduction of cancer risk in obesity and type 2 diabetes. Large durable weight loss, as such, appears to afford protection against cancer, but with good glucose control the number of cancer cases also drops radically, a University of Gothenburg study shows.
That obesity is a risk factor for both type 2 diabetes and several types of cancer is a known fact. Similarly, intentional weight loss through, for example, bariatric surgery often results in amelioration of diabetes and many patients achieve normal blood-glucose control.
I patients with obesity, cancer risk, too, can be reduced after major, long-lasting weight loss. However, there have been relatively few studies on the association between weight loss, risk of cancer and glucose control in patients with both obesity and type 2 diabetes.
The present study, published in the journal Diabetes Care, used data from the “SOS” (Swedish Obese Subjects) intervention trial, which is led and coordinated from the University of Gothenburg, as well as data from other sources, such as the Swedish Cancer Registry.
Cancer risk 60 percent lower
The researchers studied a group of 393 people with type 2 diabetes who underwent bariatric surgery, and compared them with a control group of 308 people with the same clinical characteristics; i.e., they had severe obesity and type 2 diabetes, but had not undergone bariatric surgery. In other respects, such as in terms of gender composition, blood glucose, and smoking, the two groups were comparable.

Cataracts affect most older adults at risk for dementia, and now researchers are finding strong evidence that cataract surgery is associated with a lower risk of developing dementia.
The Adult Changes in Thought (ACT) study is a long-standing, Seattle-based observational study at Kaiser Permanente Washington of more than 5,000 participants older than 65. Based on the longitudinal data of over 3,000 ACT study participants, researchers have now found that subjects who underwent cataract surgery had nearly 30% lower risk of developing dementia from any cause compared with those who did not. This lowered risk persisted for at least a decade after surgery. Cataract surgery was also associated with lower risk of Alzheimer disease dementia specifically. The results were reported Dec. 6 in JAMA Internal Medicine.
Lead researcher Dr. Cecilia S Lee, associate professor and Klorfine Family Endowed Chair in ophthalmology at the University of Washington School of Medicine, said the observational study adjusted for a number of potential confounders, yet still yielded a strong association.
“This kind of evidence is as good as it gets in epidemiology,” Lee said. “This is really exciting because no other medical intervention has shown such a strong association with lessening dementia risk in older individuals.”
The mechanisms by which cataract surgery and lessened dementia risk are associated was not determined in this study. Researchers hypothesize that people may be getting higher quality sensory input after cataract surgery, which might have a beneficial effect in reducing the risk of dementia.
“These results are consistent with the notion that sensory input to the brain is important to brain health,” said co-author Dr. Eric B. Larson, a principal investigator of the ACT study, and senior investigator at Kaiser Permanente Washington Health Research Institute.

A new Cleveland Clinic-led study has identified sildenafil — an FDA-approved therapy for erectile dysfunction (Viagra) and pulmonary hypertension (Ravatio) — as a promising drug candidate to help prevent and treat Alzheimer’s disease.
According to findings published in Nature Aging, the research team, led by Feixiong Cheng, Ph.D., of Cleveland Clinic’s Genomic Medicine Institute, used computational methodology to screen and validate FDA-approved drugs as potential therapies for Alzheimer’s disease. Through a large-scale analysis of a database of more than 7 million patients, they determined that sildenafil is associated with 69% reduced incidence of Alzheimer’s disease, indicating the need for follow-up clinical trial testing of the drug’s efficacy in patients with the disease.
“Recent studies show that the interplay between amyloid and tau is a greater contributor to Alzheimer’s than either by itself,” said Dr. Cheng. “Therefore, we hypothesized that drugs targeting the molecular network intersection of amyloid and tau endophenotypes should have the greatest potential for success.”
Without the development of effective new treatments, Alzheimer’s disease is set to impact 13.8 million Americans by 2050, underscoring the need for rapid development of prevention and treatment strategies. Drug repurposing — use of an existing drug for new therapeutic purposes — offers a practical alternative to the costly and time-consuming traditional drug discovery process.
“This paper is an example of a growing area of research in precision medicine where big data is key to connecting the dots between existing drugs and a complex disease like Alzheimer’s,”said Jean Yuan, M.D., Ph.D., program director of Translational Bioinformatics and Drug Development at the National Institute on Aging (NIA), part of the National Institutes of Health (NIH), which funded this research. “This is one of many efforts we are supporting to find existing drugs or available safe compounds for other conditions that would be good candidates for Alzheimer’s disease clinical trials.”
Dr. Cheng’s team has found that understanding subtypes (endophenotypes) of neurodegenerative diseases such as Alzheimer’s disease may help to reveal common underlying mechanisms and lead to discovery of actionable targets for drug repurposing.

Our body must constantly defend itself against bacteria and viruses. It generates millions of different antibodies, which are selected to recognise the enemy and trigger the best possible immune response. Scientists use these antibodies to for therapeutic purposes to target proteins and disrupt their harmful. However, identifying the small molecules that will form the basis of the drug is a long and tedious process. Chemists at the University of Geneva (UNIGE), Switzerland, have developed a technique inspired by the theory of Darwinian evolution: amplifying the best combinations and generating diversity allows biology to find solutions to new problems. They have created a new methodology that rapidly generates millions of combinations of small molecules through programmed assembly using DNA-pairing processes, finding the best possible combination to counter a target protein within two weeks. These results, published in the journal Nature Chemistry, will open up a new and untapped space for drug development.
The way drugs work is based on the molecular recognition of a target protein involved in the disease, in order to disarm it. To do this, scientists use high-throughput screening to identify which molecule could become a drug, specifically targeting the protein of interest. Over the last ten years, the technique has been improved by encoding small molecules with DNA tags that simplify their identification, as DNA is easy to decode.
Drawing inspiration from Darwinian evolutionary forces to find efficient assemblies
Today, chemists at the UNIGE have gone one step further, drawing inspiration from Darwin’s theories: “Biology always finds a solution to a problem, explains Nicolas Winssinger, professor in the Department of Organic Chemistry at the Faculty of Science, UNIGE, and the corresponding author of the study. This is the principle of natural evolution, which consists of amplifying the best individuals, while generating diversity to adapt and survive changing conditions. That’s what we’ve set up for small molecules.” Indeed, the scientists have developed a technology that generates diversity by creating more than 100 million assemblies of molecules via their DNA, which they then select to best match a particular protein.
“We were inspired by the characteristics of antibodies that recognise target proteins and sought to mimic them in the form of simpler molecules to allow them to be assembled in different combinations, directed by DNA sequences,” explains Nicolas Winssinger. These combinations are then selected and amplified several times to find the best possible match with the protein to be targeted, all in one to two weeks, compared with months or even a year for traditional high-throughput screening.
A proven, easily reproducible and inexpensive technique
To validate the effectiveness of this methodology, the Geneva team focused on the PD-L1 protein, which protects cancer cells by diverting the immune system. “Thanks to our methodology, we quickly identified an assembly that specifically targets PD-L1, confirming that it works effectively,” says Nicolas Winssinger.
This technique, which is easy to reproduce in any laboratory in the world, costs only a few thousand francs, compared with millions for high-throughput screening. “By exploiting the evolutionary forces highlighted by Darwin, we can now improve our molecular assemblies and open up a new space of possible combinations that has not yet been exploited, in order to create new, more effective drugs,” concludes the Geneva researcher.
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Species extinction, the introduction of non-native plants, climate change, and pollution are all major drivers of changes in biological communities due to human activity. Though these patterns have been well studied, most investigations focus on only one of these drivers and often in a localized area rather than more globally.
In a study published December 6 in Nature Communications researchers have compiled a dataset of over 200,000 plant species worldwide to demonstrate the extent to which species extinctions and non-native invasive plants reorganize plant communities in the Anthropocene, the current geological age dominated by human activity.
“A lot is known about how animal communities are responding to global change,” said lead author Barnabas H. Daru, former postdoctoral fellow at the Harvard University Herbaria and in the Department of Organismic and Evolutionary Biology, “but we know so little about how plant communities are responding to global change.”
Daru began the project several years ago by mapping North American biomes while working with the lab of senior author Professor Charles C. Davis in the Department of Organismic and Evolutionary Biology and Curator of Vascular Plants at the Harvard University Herbaria at Harvard University. As the project progressed, Daru expanded it to include the biomes of Australia, South Africa, Europe and China. The study examined how landscapes and communities of plants change, especially following the bridging of the eastern and western hemispheres roughly 500 years ago. The analyses captured on a large scale the striking loss of species’ distinctiveness across landscapes leading Daru to ask what are the contributing factors to these changes.
Daru noted that extinction and the naturalization of non-native species cause biotic homogenization — the gradual replacement of native species by locally spreading non-native species — leading to a reduction in species and evolutionary differences. Biotic homogenization can also have negative impacts on key ecosystem functions. To asses these impacts Daru moved from mapping biomes to quantifying these processes.
While both extinction and the naturalization of non-native plants can drive homogenization, the study showed that regardless of extinction scenario, the strongest contributor to biotic homogenizations resulted from non-native plants naturalized by humans. These changes occurred over a short evolutionary span of approximately 500 years and were facilitated — intentionally or unintentionally — by humans moving organisms around the landscape.
“Plants are foundation species. They sustain food chains and drive terrestrial ecosystem productivity,” said Davis. “This means that plant distributions often underlie the biogeographic histories of other organisms so it’s important to understand the impact of anthropogenic change in plant communities.”
“The study’s results highlight yet another imprint of the Anthropocene and demonstrate the profound influence humans exert on regional biotas beyond changes in species richness,” said co-author Professor T. Jonathan Davies, The University of British Columbia.
Daru developed the database GreenMaps from global digitized Herbaria collections including Harvard University Herbaria, National Herbarium of the South African National Biodiversity Institute, Australian Virtual Herbarium, Consortium for Northeast Herbaria, and Atlas Florae Europaeae. Daru’s creation of a global map helped close the knowledge gap in the global distributions of plant occurrence records by generating predicted distributions for more than 200,000 species worldwide.
“This study demonstrates the enormous value and utility of natural history collections far beyond their original use,” said Davis, “especially once they are digitized and mobilized online.”
Of the more than 200,000 species, 10,000 were known to be invasive plants naturalized to other parts of the world. Over 1,000 were species that had recently gone extinct (within the last three to four hundred years).
“Invasive species are naturalized intentionally or unintentionally,” said Daru, “but ultimately these naturalizations were aided by humans on an ever-shrinking planet.”

SharecloseShare pageCopy linkAbout sharingImage source, Getty ImagesThe impotence pill Viagra may be a useful treatment against Alzheimer’s disease, say US researchers who have been studying its effects in the brain. Tests in cells suggest the drug targets some of the proteins that accumulate in this type of dementia. The Cleveland team also analysed a database of 7m patients and found men who were on the drug had a lower risk of Alzheimer’s. More studies on it are worthwhile, they say in the journal Nature Aging. Work like this is exciting, say experts, because repurposing an existing drug could be quicker, simpler and cheaper than finding and developing a brand new treatment. US approves first new Alzheimer’s drug in 20 yearsThe blue pillViagra, also known as sildenafil, was originally designed as a heart drug because of its main action – improving blood flow by relaxing or widening blood vessels. Doctors then discovered it was having a similar effect elsewhere in the body, including the arteries of the penis, and it was developed into a successful treatment for erectile dysfunction. But experts think it could have other uses too. Sildenafil is already used in men and women for a lung condition called pulmonary hypertension. And scientists have recently been exploring whether it might help people at risk of vascular dementia – the second most common form of dementia after Alzheimer’s – which occurs when reduced blood flow damages the brain. Now researchers believe it may help Alzheimer’s as well. The exact cause of this type of dementia is not fully understood, but doctors do know that abnormal protein deposits collect in the brains of people who have it. The Cleveland team found: High doses of the drug (larger than a person would normally take) increased brain cell growth and reduced protein accumulation in lab studies of human tissuePeople on sildenafil were less likely to develop Alzheimer’s than those not taking this medication, based on personal medical data spanning six years and involving more than 7.23m individuals Lead investigator Dr Feixiong Cheng said the findings were encouraging, but needed more exploring: “Because our findings only establish an association between sildenafil use and reduced incidence of Alzheimer’s disease, we are now planning a mechanistic trial and a phase II randomized clinical trial to test causality and confirm sildenafil’s clinical benefits for Alzheimer’s patients.”UK brain research expert Prof Tara Spires-Jones, from the University of Edinburgh, said: “More work will be needed to know whether this drug can indeed lower risk for Alzheimer’s disease.”While these data are interesting scientifically, based on this study, I would not rush out to start taking sildenafil as a prevention for Alzheimer’s disease.”Dr Jack Auty, lecturer in the Medical Sciences at the University of Tasmania, said: “In the field of Alzheimer’s disease research, we have been excited by many drugs over the years, only to have our hopes dashed in clinical trials. I will be following this research group and the research around sildenafil closely.”Nature AgingThe BBC is not responsible for the content of external sites.

An international research team has used the X-ray laser European XFEL to gain new insights into how radiation damage occurs in biological tissue. The study reveals in detail how water molecules are broken apart by high-energy radiation, creating potentially hazardous radicals and electrically charged ions, which can go on to trigger harmful reactions in the organism. The team led by Maria Novella Piancastelli and Renaud Guillemin from the Sorbonne in Paris, Ludger Inhester from DESY and Till Jahnke from European XFEL is presenting its observations and analyses in the scientific journal Physical Review X.
Since water is present in every known living organism, the splitting of the water molecule H2O by radiation, called the photolysis of water, is often the starting point for radiation damage. “However, the chain of reactions that can be triggered in the body by high-energy radiation is still not fully understood,” explains Inhester. “For example, even just observing the formation of individual charged ions and reactive radicals in water when high-energy radiation is absorbed is already very difficult.”
To study this sequence of events, the researchers shot the intense pulses from the X-ray laser at the water vapour. Water molecules normally disintegrate on absorbing a single such high-energy X-ray photon. “Due to the particularly intense pulses from the X-ray laser, it was even possible to observe water molecules absorbing not just one, but two or even more X-ray photons before their debris flew apart,” Inhester reports. This gives the researchers a glimpse of what goes on inside the molecule after the first absorption of an X-ray photon.
“The movement of the molecule between two absorption events leaves a clear fingerprint, in other words, its fragments fly apart in a very specific, characteristic way,” says Piancastelli. “By carefully analysing this fingerprint, as well as using detailed simulations, we were able to draw conclusions about the ultra-fast dynamics of the water molecule after it had absorbed the first X-ray photon.” The team measured the directions in which the fragments travelled and their speeds using a so-called reaction microscope. This allowed the scientists to record the disintegration of the water molecule, which lasted only a few femtoseconds (quadrillionths of a second), in a kind of slow-motion movie.
It turns out that the disintegration of the water molecule is much more complicated than initially expected. The water molecule (H2O) starts to stretch and expand before eventually breaking apart. After only ten femtoseconds, the two hydrogen atoms (H), which are normally attached to the oxygen atom (O) at an angle of 104 degrees, can build up so much momentum as to face each other at an angle of around 180 degrees. As a result, the oxygen atom is not in fact flung away hard when the molecule breaks up, because the momenta of the two hydrogen nuclei largely balance each other out as they fly off, leaving the oxygen virtually at rest in the middle. In an aqueous environment, this free oxygen radical can then easily lead to further potentially harmful chemical reactions.
“In our research, we succeeded for the first time in taking a closer look at the dynamics of a water molecule after it absorbs high-energy radiation,” says Inhester, who works at the Centre for Free-Electron Laser Science (CFEL), a collaboration between DESY, the University of Hamburg and the Max Planck Society. “In particular, we were able to characterise the formation of the oxygen radical and the hydrogen ions more precisely, as well as the way this process unfolds over time. This disintegration of the water molecule is an important first step in the further chain of reactions that ultimately lead to radiation damage.”
The analysis adds to the overall picture of radiation effects on water. A previous study involving some members of the same team had explored the detailed dynamics of the formation of so-called free radicals by less energetic radiation in water. The processes observed there have similar dynamics to the secondary processes in the absorption of high-energy radiation now under investigation. The newly gained insights address elementary questions about reaction dynamics in water, which are to be further investigated at the Centre for Molecular Water Science (CMWS) currently being set up with international partners at DESY.
The new experiments on single water molecules were among the first performed with the new COLTRIMS reaction microscope at the experimental station SQS of the European XFEL. “The results show that we will be also able to look at other solvents and molecules with more complex structure, such as ethanol or cyclic compounds, which are of great interest in chemistry and other disciplines,” says Jahnke.
Involved in the study were researchers from the universities of Frankfurt am Main, Freiburg, Hamburg and Kassel as well as Gothenburg, Lund and Uppsala in Sweden and Turku in Finland, from the Fritz Haber Institute of the Max Planck Society and the Max Planck Institute for Nuclear Physics, from Lawrence Berkeley National Laboratory and Kansas State University in the USA, the National Research Council and the Technical University of Milan in Italy, the Sorbonne in Paris, European XFEL and DESY.