212CNO07AUG2015
CNO Report 212
Release Date 14 AUG 2015
Draft Report Compiled by
Ralph Turchiano
1. Fatty acid increases performance of cellular powerhouse
2. Probiotics improve behavioral symptoms of chronic inflammatory diseases in mice
3. Omega-3 fatty acids may help improve treatment and quality of life in cancer patients
4. McMaster scientists show a link between intestinal bacteria and depression
5. An all-natural sunscreen derived from algae
6. Red grape chemical may help prevent bowel cancer, but less is more
7. The evolutionary link between diet and stomach acidity
8. Consuming highly refined carbohydrates increases risk of depression
9. BIDMC researchers identify new vitamin B3 pathway
10. Pesticides: More toxic than previously thought?
11. Study finds association between blood levels of trace metals and risk of glaucoma
12. Scientists show how aging cripples the immune system, suggesting benefits of antioxidants
13. Common medications could delay brain injury recovery
14. The Lancet Diabetes & Endocrinology: Universal iodine supplementation during pregnancy could offer huge cost savings
15. Chickenpox vaccination does increase shingles cases, but mainly in young adults
16. Trans fats, but not saturated fats, linked to greater risk of death and heart disease
17. Protein-packed breakfast prevents body fat gain in overweight teens
18. Children who are leaner report eating more polyunsaturated fatty acids
Public Release: 28-Jul-2015
Fatty acid increases performance of cellular powerhouse
Fundamentally new biological signaling pathway discovered
German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ)
Mitochondria are essential to all higher forms of life. Every animal and plant depends on these small intracellular structures. Mitochondria have multiple tasks: Since they generate most of the cell’s biochemical energy, they are referred to as the powerhouses of the cell. In addition, they are responsible for producing and breaking down amino acids and fats. They also regulate cellular death, called apoptosis.
As a result, the spectrum of diseases that are linked to mitochondrial defects is wide, ranging from severe muscular and nervous disorders to neurodegenerative diseases as well as all symptoms of aging.
“It was by pure chance that we discovered this completely new control mechanism of mitochondrial function,” says first author Deniz Senyilmaz, who works in Aurelio Teleman’s group at the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ). In collaboration with colleagues from Cambridge, Teleman and his team had planned to investigate the metabolism of long-chain fatty acids. For this purpose, the researchers bred flies whose cells were unable to produce stearic acid, a fatty acid that is composed of 18 carbon atoms. Animals with this defect did not develop beyond the pupal stage and were not viable afterwards.
Teleman and his team were curious to find out why this happened. They then discovered a highly complex biological control mechanism that regulates the fusion – as well as fragmentation – of mitochondria and, hence, the performance of these organelles.
The key element in this control mechanism is the transferrin receptor, which binds stearic acid. “For the first time in biological research, we have found out that stearic acid, which up until now has been believed to be simply a metabolic product, also has signaling function,” says Teleman. The researchers demonstrated that mitochondrial control via stearic acid works not only in flies but also in the HeLa human cancer cell line.
When the researchers added stearic acid to fly food, the animals’ mitochondria fused; when they kept fatty acid levels low, the organelles fragmented. “If using stearic acid as a food additive improves the performance of normal mitochondria, then it might do the same in pathogenically dysfunctional mitochondria,” Teleman explained, describing their experimental approach.
The researchers studied flies that exhibit Parkinson’s-like symptoms resulting from a mitochondrial defect in the PINK and Parkin proteins and are recognized as a model system for studying this neurodegenerative disease. When the affected animals were fed stearic acid with their food, their motor skills and energy balance improved and they survived for much longer.
“This opens up the fascinating possibility of using a food additive to alleviate symptoms in patients with mitochondrial disease,” says Teleman. “However, this still is a dream of the future, because we do not yet know whether human cells respond in the same way as fly cells do to increased quantities of stearic acid in the diet. Our diet naturally contains much more stearic acid than fly food does. Therefore, a further increase might not make any more difference.”
Public Release: 28-Jul-2015
Probiotics improve behavioral symptoms of chronic inflammatory diseases in mice
Society for Neuroscience
WASHINGTON, DC — Probiotics may improve the behavioral symptoms of chronic inflammatory diseases by altering communication between the immune system and the brain, according to an animal study published July 29 in the Journal of Neuroscience. Chronic inflammatory diseases such as rheumatoid arthritis and inflammatory bowel disease are associated with behavioral symptoms that include fatigue, depression, and social withdrawal. Researchers at the University of Calgary fed probiotics to mice with liver inflammation and found that the treatment reduced these behaviors.
The gastrointestinal tract is inhabited by a mass of microorganisms called the microbiota, which supports digestion and immune system health. Probiotics are live bacteria and yeasts that are commonly ingested to support the microbiota, and previous research has demonstrated that probiotics can have beneficial effects on mood and cognition. The mechanism of probiotics’ effects on the brain is unclear, but it has been linked to changes in the immune system.
In this study, mice with liver inflammation were fed either a probiotic mixture or a placebo. The researchers gauged behavioral symptoms by measuring the amount of time the mice spent in social behaviors compared to time spent in isolation. Although it is unclear how inflammatory diseases lead to changes in brain function and behavior, previous research implicates the increased production of the inflammatory signaling molecule tumor necrosis factor alpha (TNF-α). Thus, the researchers also measured the amount of TNF-α circulating in the blood and the amount of activated immune cells in the brain.
They found that:
· Mice that received the probiotics spent more time engaging in social behaviors compared to mice that received a placebo.
· Mice that received the probiotics had lower blood levels of TNF-α and fewer activated immune cells in the brain compared to mice that received a placebo.
· Probiotics did not alter the severity of liver inflammation.
The findings suggest that probiotics improved behavioral symptoms by altering communication between the immune system and the brain, the researchers said. The results suggest that, “in the setting of inflammatory disease, eating probiotics may be a novel way to improve the disease-associated symptoms that negatively impact the lives of patients,” study author Mark Swain said.
The results have broader implications for the field as well, said Keith Kelley, an immunophysiologist at the University of Illinois at Urbana-Champaign who was not involved in the study. “The global implication of these data is that the gut microbiome can perhaps be manipulated to not only regulate immunity but also to regulate the neural circuitry that affects behavior.”
Public Release: 28-Jul-2015
Omega-3 fatty acids may help improve treatment and quality of life in cancer patients
American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.)
Adding omega-3 fatty acids to anti-tumor medications may improve treatment response and quality of life for cancer patients according to a new study by researchers at the University Hospitals of Leicester in the United Kingdom.
The study, published today in the OnlineFirst version of the Journal of Parenteral and Enteral Nutrition (JPEN), the research journal of the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.), examined 50 patients with advanced pancreatic cancer.
Patients were given 1,000 mg of gemcitabine weekly followed by up to 100 g of omega-3 rich lipid emulsion for three weeks followed by a rest week. This was continued for up to six cycles, progression, unacceptable toxicity, patient request, or death.
The study found evidence of activity in response and disease stabilization rates, reduction in liver metastasis volume, and improved quality of life scores in this group of patients.
While this is the first study to use omega-3 fatty acids with a chemotherapy agent in a cancer setting, the researchers believe the results are encouraging enough to warrant further investigation in a randomized phase III trial.
Public Release: 28-Jul-2015
McMaster scientists show a link between intestinal bacteria and depression
Exploring the role of intestinal microbiota in the altered behavior that is a consequence of early life stress
McMaster University
Hamilton, ON (July 28, 2015) – Scientists from the Farncombe Family Digestive Health Research Institute at McMaster University have discovered that intestinal bacteria play an important role in inducing anxiety and depression.
The new study, published today in Nature Communications, is the first to explore the role of intestinal microbiota in the altered behaviour that is a consequence of early life stress.
“We have shown for the first time in an established mouse model of anxiety and depression that bacteria play a crucial role in inducing this abnormal behaviour,” said Premysl Bercik, senior author of the paper and an associate professor of medicine with McMaster’s Michael G. DeGroote School of Medicine. “But it’s not only bacteria, it’s the altered bi-directional communication between the stressed host — mice subjected to early life stress — and its microbiota, that leads to anxiety and depression.”
It has been known for some time that intestinal bacteria can affect behaviour, but much of the previous research has used healthy, normal mice, said Bercik.
In this study, researchers subjected mice to early life stress with a procedure of maternal separation, meaning that from day three to 21, newborn mice were separated for three hours each day from their mothers and then put back with them.
First, Bercik and his team confirmed that conventional mice with complex microbiota, which had been maternally separated, displayed anxiety and depression-like behaviour, with abnormal levels of the stress hormone corticosterone. These mice also showed gut dysfunction based on the release of a major neurotransmitter, acetylcholine.
Then, they repeated the same experiment in germ-free conditions and found that in the absence of bacteria mice which were maternally separated still have altered stress hormone levels and gut dysfunction, but they behaved similar to the control mice, not showing any signs of anxiety or depression.
Next, they found that when the maternally separated germ-free mice are colonized with bacteria from control mice, the bacterial composition and metabolic activity changed within several weeks, and the mice started exhibiting anxiety and depression.
“However, if we transfer the bacteria from stressed mice into non stressed germ-free mice, no abnormalities are observed. This suggests that in this model, both host and microbial factors are required for the development of anxiety and depression-like behavior. Neonatal stress leads to increased stress reactivity and gut dysfunction that changes the gut microbiota which, in turn, alters brain function,” said Bercik.
He said that with this new research, “We are starting to explain the complex mechanisms of interaction and dynamics between the gut microbiota and its host. Our data show that relatively minor changes in microbiota profiles or its metabolic activity induced by neonatal stress can have profound effects on host behaviour in adulthood.”
Bercik said this is another step in understanding how microbiota can shape host behaviour, and that it may extend the original observations into the field of psychiatric disorders.
“It would be important to determine whether this also applies to humans. For instance, whether we can detect abnormal microbiota profiles or different microbial metabolic activity in patients with primary psychiatric disorders, like anxiety and depression,” said Bercik.
Public Release: 29-Jul-2015
An all-natural sunscreen derived from algae
American Chemical Society
For consumers searching for just the right sunblock this summer, the options can be overwhelming. But scientists are now turning to the natural sunscreen of algae — which is also found in fish slime — to make a novel kind of shield against the sun’s rays that could protect not only people, but also textiles and outdoor materials. They report on their development in the journal ACS Applied Materials & Interfaces.
Existing sunblock lotions typically work by either absorbing ultraviolet rays or physically blocking them. A variety of synthetic and natural compounds can accomplish this. But most commercial options have limited efficiency, pose risks to the environment and human health or are not stable. To address these shortcomings, Vincent Bulone, Susana C. M. Fernandes and colleagues looked to nature for inspiration.
The researchers used algae’s natural sunscreen molecules, which can also be found in reef fish mucus and microorganisms, and combined them with chitosan, a biopolymer from crustacean shells. Testing showed their materials were biocompatible, stood up well in heat and light, and absorbed both ultraviolet A and ultraviolet B radiation with high efficiency.
ublic Release: 29-Jul-2015
Red grape chemical may help prevent bowel cancer, but less is more
Cancer Research UK
Resveratrol, a chemical found in red grapes, is more effective in smaller doses at preventing bowel cancer in mice than high doses, according to new research* published today (Wednesday) in the journal Science Translational Medicine.
Previous research looked at high doses of purified resveratrol to study its potential to prevent cancer. This is the first study to look at the effects of a lower daily dose – equivalent to the amount of resveratrol found in one large (approx. 250ml) glass of red wine – comparing it with a dose 200 times higher.
Results from bowel cancer-prone mice given the smaller dose showed a 50 per cent reduction in tumour size while the high dose showed a 25 per cent reduction. Lower doses of resveratrol were twice as effective as the higher dose in stopping tumours growing, although this effect was only seen in animals fed a high-fat diet.
Samples of tumours from bowel cancer patients given different doses of resveratrol showed that even lower doses can get into cancer cells and potentially affect processes involved in tumour growth.
Resveratrol is a naturally-occurring chemical found in grape skins and other plants. Laboratory studies have suggested that it may have anti-cancer properties, although results from human trials have been mixed.
This study opens up new avenues for the role of purified resveratrol in preventing cancer, but suggests that it may only be effective for people with a specific genetic make-up, particular diets and lifestyles.
And it doesn’t mean drinking red wine reduces cancer risk, as drinking alcohol increase the chances of developing the disease.
Karen Brown, professor of translational cancer research at the University of Leicester, said: “For the first time, we’re seeing that less resveratrol is more. This study shows that low amounts may be better at preventing tumours than taking a high dose.
“The same might be true for other plant-derived chemicals and vitamins that are also being studied for cancer prevention. There should be more research looking at the effects of low doses. But this is early laboratory research and the next stage is for clinical trials to confirm whether resveratrol has the same effects in people at high risk of bowel cancer.”
Dr Julie Sharp, Cancer Research UK’s head of health information, said: “This research doesn’t mean that having a glass of red wine will reduce your risk of cancer because you can’t separate the resveratrol from the alcohol. And the increase in cancer risk linked to alcohol outweighs any possible benefits of the resveratrol.
“It’s a fascinating study but we need much more research to understand all the pros and cons of someone taking resveratrol to prevent bowel cancer. However, we do know that keeping a healthy weight along with a balanced diet low in red and processed meat with lots of fibre including fruit and vegetables can stack the odds in your favour to lower your risk of developing the disease.”
Public Release: 29-Jul-2015
The evolutionary link between diet and stomach acidity
North Carolina State University
An analysis of data on stomach acidity and diet in birds and mammals suggests that high levels of stomach acidity developed not to help animals break down food, but to defend animals against food poisoning. The work raises interesting questions about the evolution of stomach acidity in humans, and how modern life may be affecting both our stomach acidity and the microbial communities that live in our guts.
“We started this project because we wanted to better understand the relationship between stomach acidity, diet and the microbes that live in the guts of birds and mammals,” says DeAnna Beasley, a postdoctoral researcher at North Carolina State University and corresponding author of a paper on the work. “Our idea was that this could offer some context for looking at the role of the human stomach in influencing gut microbes, and what that may mean for human health.”
The research team – including scientists from Washington University and the University of Colorado, Boulder – examined all of the existing literature on stomach acidity in birds and mammals, and found data on 68 species. They then collected data on the natural feeding habits of each species. The researchers then ran an analysis to see how feeding behavior was related to stomach acidity.
The researchers found that scavengers, or species that eat food at high risk of microbial contamination, have more acidic stomachs. This acidity allows the stomach to act as a filter, effectively controlling which microbes can pass through the stomach to the gut.
“The finding confirms our hypothesis, but you have to get that confirmation before moving forward,” Beasley says. “The next step will be for scientists to examine the microbial ecosystems in the guts of these animals to see how these ecosystems have evolved. Do animals with high stomach acidity have smaller or less diverse populations of gut microbes? Or do they simply host microbes that can survive in acidic environments?”
One surprise was that, while the researchers classified humans as omnivores, human stomachs have the high acidity levels normally associated with scavengers. Meanwhile, the literature shows that medical treatments – from surgery to antacids – can significantly alter the acidity in a human stomach.
“This raises significant questions about how humans have evolved, our species’ relationship with food over time, and how modern changes in diet and medicine are affecting our stomachs, our gut microbes and – ultimately – our health,” Beasley says. “Those are questions the research community is already exploring, and the answers should be interesting.”
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The paper, “The Evolution of Stomach Acidity and Its Relevance to the Human Microbiome,” will be published July 29 in the journal PLOS ONE. The paper was co-authored by Rob Dunn of NC State, Amanda Koltz of Washington University, and Joanna Lambert and Noah Fierer of UC Boulder.
Public Release: 5-Aug-2015
Consuming highly refined carbohydrates increases risk of depression
Columbia University Medical Center
NEW YORK, NY, August 5, 2015 – A diet high in refined carbohydrates may lead to an increased risk for new-onset depression in postmenopausal women, according to a study published in The American Journal of Clinical Nutrition.
The study by James Gangwisch, PhD and colleagues in the department of psychiatry at Columbia University Medical Center (CUMC) looked at the dietary glycemic index, glycemic load, types of carbohydrates consumed, and depression in data from more than 70,000 postmenopausal women who participated in the National Institutes of Health’s Women’s Health Initiative Observational Study between 1994 and 1998.
Consumption of carbohydrates increases blood sugar levels to varying degrees, depending on the type of food ingested. The more highly refined the carbohydrate, the higher its score on the glycemic index (GI) scale. The GI scale, which goes from 0-100, measures the amount of sugar found in the blood after eating. Refined foods such as white bread, white rice, and soda trigger a hormonal response in the body to reduce blood sugar levels. This response may also cause or exacerbate mood changes, fatigue and other symptoms of depression.
The investigators found that progressively higher dietary GI scores and consumption of added sugars and refined grains were associated with increased risk of new-onset depression in post-menopausal women. Greater consumption of dietary fiber, whole grains, vegetables and non-juice fruits was associated with decreased risk. This suggests that dietary interventions could serve as treatments and preventive measures for depression. Further study is needed to examine the potential of this novel option for treatment and prevention, and to see if similar results are found in the broader population.
Public Release: 6-Aug-2015
BIDMC researchers identify new vitamin B3 pathway
Findings could lead to new treatments to improve metabolism and lower cholesterol
Beth Israel Deaconess Medical Center
BOSTON – Researchers at Beth Israel Deaconess Medical Center (BIDMC) have identified a new vitamin B3 pathway that regulates liver metabolism. The discovery provides an opportunity to pursue the development of novel drug therapies to address obesity, type 2 diabetes and related metabolic diseases.
Published in the August 2015 issue of Nature Medicine, the new findings show that a small molecule called N1-methylnicotinamide prevents metabolic complications caused by a high-fat diet.
“Our laboratory investigates the metabolic effects of nicotinamide adenine dinucleotide [NAD+], a metabolite derived from a form of vitamin B3 called nicotinamide,” explained senior author Pavlos Pissios, PhD, an investigator in the Division of Endocrinology, Diabetes and Metabolism at BIDMC and Assistant Professor of Medicine at Harvard Medical School. NAD+ is central to intermediary metabolism, the intracellular process by which food is converted into cellular components in the body.
“Like reservatrol, which is found in red wine, NAD+ boosts the effects of the protein sirtuin 1 [Sirt1], which is known to provide many health benefits,” said Pissios. “Interest in the metabolic effects of NAD+ has spurred the production of several new dietary supplements to improve metabolic health and delay aging. While these results have yet to be demonstrated in humans, recent research has shown that boosting tissue levels of NAD+ can improve health and reduce metabolic complications in mice that have been fed a high-fat diet.”
The liver plays a central role in all metabolic processes, including breaking down fats to produce energy. Because a number of different proteins are involved in the metabolic effects of NAD+, Pissios and his colleagues hypothesized that there might be an as-yet-unidentified vitamin B3 pathway that was directly regulating liver metabolism. “We thought that, in addition to boosting NAD+, vitamin B3 might be positively impacting liver metabolism by acting directly on another pathway,” he explained.
To test this hypothesis, the researchers conducted a variety of experiments that assessed these proteins. Their results showed that nicotinamide N-methyltransfersase (NNMT), a “clearance” enzyme that helps the body excrete excess vitamin B3, also plays a more prominent metabolic role.
“Our lab had been gathering evidence that NNMT not only functions to clear nicotinamide from the liver, but is also involved in the regulation of liver metabolism,” said Pissios. “We confirmed this in our new study, which found that N1-methylnicotinamide, the product of nicotinamide methylation by NNMT, increases Sirt1 protein levels and improves metabolism.”
In subsequent experiments, Pissios and colleagues found that NNMT correlated positively with Sirt1 and a healthy metabolic profile in mice, and also showed that humans with low cholesterol and low triglycerides exhibited high levels of NNMT and Sirt1 in their livers.
“Since N1-methylnicotinamide is a small molecule, we were able to feed it directly to mice to find out if it would prevent the metabolic complications caused by a high-fat diet,” said Pissios. As predicted, N1-methylnicotinamide increased liver Sirt1 protein and suppressed triglyceride and cholesterol synthesis resulting in a healthier liver — with fewer inflammatory markers, less liver fat and lower cholesterol compared to control groups.
“We have now identified a new vitamin B3 pathway that regulates liver metabolism and provides us with an opportunity to pursue development of novel treatments for metabolic diseases,” said Pissios.
Public Release: 6-Aug-2015
Pesticides: More toxic than previously thought?
Changes in personality of jumping spiders suggest effects of insecticide exposure may have been underestimated
McGill University
Insecticides that are sprayed in orchards and fields across North America may be more toxic to spiders than scientists previously believed. A McGill research team reached this conclusion after looking at changes in the behaviour of individual Bronze Jumping Spiders both before and after exposure to Phosmet, a widely used broad spectrum insecticide. It is a finding with far-reaching implications for agricultural production and ecosystem health.
“Bronze jumping spiders play an important role in orchards and fields, especially at the beginning of the agricultural season, by eating many of the pests like the oblique-banded leafroller, a moth that attacks young plants and fruit,” says Raphaël Royauté, a former McGill PhD student whose study on the subject was published in Functional Ecology recently. “Farmers spray insecticides on the plants to get rid of these same pests, and it was thought that it had little significant effect on the spiders’ behaviours. But we now know that this isn’t the case.”
The researchers discovered this fact by focusing on the way that exposure to insecticide affected the behaviour of individual spiders, including things like their ability to leap on prey and their interest in exploring new territory, both of which are crucial to their survival and to their role in keeping down pests.
Spider personalities
Even jumping spiders have personalities scientists have discovered. A “shy” individual will not make the same choices as a “bold” individual. This means that some individuals, because of their personality type, will capture more prey than others, and will therefore have a larger effect on local ecosystems.
“Most individuals have an individual signature in their behaviours, what scientist call “personality types” says Royauté. “Some individuals are willing to take risks when predators are present, explore new territories faster, or capture prey more quickly. But the effects of insecticides on personality types remains poorly described.”
The researchers found that, in general, the behaviour of spiders became more “unpredictable” and individuals behaved less according to their personality type once they were exposed to insecticide. This could be because some individuals are much more sensitive to the insecticide than others. Interestingly, they also found that male and female spiders were affected differently. Males who had been exposed to the insecticide were able to continue to capture prey as they had before, but “lost” their personality type when exploring their environment. Individual females, on the other hand, were much more affected in their ability to capture prey.
“By looking at the way that insecticides affect individual spider behaviours, rather than averaging out the effects on the spider population as a whole, as is traditionally done in scientific research, we are able to see some significant effects that we might have otherwise missed,” says Chris Buddle, who co-authored the paper. “It means we can measure the effects of insecticides before any effects on the spider population as a whole are detected, and in this case, it’s raising some red flags.”
The researchers hope that this study will lead to the reevaluation of procedures used to estimate the toxicity of insecticidal compounds by encouraging other researchers to pay more attention to effects occurring at the individual level.
Public Release: 6-Aug-2015
Study finds association between blood levels of trace metals and risk of glaucoma
The JAMA Network Journals
In an analysis that included a representative sample of the South Korean population, a lower blood manganese level and higher blood mercury level were associated with greater odds of a glaucoma diagnosis, according to a study published online by JAMA Ophthalmology.
Glaucoma is the leading cause of irreversible blindness worldwide and a growing public health concern because of an aging global population. Abnormal body levels of essential elements and exposure to toxic trace metals have been postulated to contribute to the pathogenesis of diseases affecting many organ systems, including the eye, according to background information in the article.
Shan C. Lin, M.D., of the University of California, San Francisco, and colleagues investigated the relationship between body levels of 5 trace metals (manganese, mercury, lead, cadmium, and arsenic) and the prevalence of glaucoma. Blood or urine metallic element levels and information pertaining to ocular disease were available for 2,680 individuals (19 years and older) participating in the fourth Korea National Health and Nutrition Examination Survey between January 2008 and December 2009, the second and the third years of the survey (2007-2009).
After adjustment for potential confounders, analyses indicated that lower blood manganese levels and higher blood mercury levels were associated with greater glaucoma prevalence. No association was found between blood lead or cadmium levels or urine arsenic levels and a diagnosis of glaucoma in the study population.
“Future prospective investigations will be necessary to confirm these associations and to explore the role of trace elements in the pathogenesis of glaucoma, as well as possible neuroprotective effects, which could lead to novel therapeutic targets in glaucoma management,” the authors write.
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Public Release: 6-Aug-2015
Scientists show how aging cripples the immune system, suggesting benefits of antioxidants
Scripps Research Institute
JUPITER, FL, August 6, 2015 – Scientists from the Florida campus of The Scripps Research Institute (TSRI) have shown how aging cripples the production of new immune cells, decreasing the immune system’s response to vaccines and putting the elderly at risk of infection. The study goes on to show that antioxidants in the diet slow this damaging process.
The research, published August 6 in the journal Cell Reports, focused on an organ called the thymus, which produces T lymphocytes, critical immune cells that must be continuously replenished to respond to new infections.
“The thymus begins to atrophy rapidly in very early adulthood, simultaneously losing its function,” said TSRI Professor Howard Petrie. “This new study shows for the first time a mechanism for the long-suspected connection between normal immune function and antioxidants.”
Scientists have been hampered in their efforts to develop specific immune therapies for the elderly by a lack of knowledge of the underlying mechanisms of this process.
To explore these mechanisms, Dr. Petrie and his team developed a computational approach for analyzing the activity of genes in two major thymic cell types–stromal cells and lymphoid cells–in mouse tissues, which are similar to human tissues in terms of function and age-related atrophy. The team found that stromal cells were specifically deficient in an antioxidant enzyme called catalase, which resulted in elevated levels of the reactive oxygen by-products of metabolism and, subsequently, accelerated metabolic damage.
To confirm the central role of catalase, the scientists increased levels of this enzyme in genetically altered animal models, resulting in preservation of thymus size for a much longer period. In addition, animals that were given two common dietary antioxidants, including vitamin C, were also protected from the effects of aging on the thymus.
Taken together, the findings provide support for the “free-radical theory” of aging, which proposes that reactive oxygen species such as hydrogen peroxide, produced during normal metabolism, cause cellular damage that contributes to aging and age-related diseases.
While other studies have suggested that sex hormones, particularly androgens such as testosterone, play a major role in the aging process, it fails to answer the key question–why does the thymus atrophy so much more rapidly than other body tissues?
“There’s no question that the thymus is remarkably responsive to androgens,” Dr. Petrie noted, “but our study shows that the fundamental mechanism of aging in the thymus, namely accumulated metabolic damage, is the same as in other body tissues. However, the process is accelerated in the thymus by a deficiency in the essential protective effects of catalase, which is found at higher levels in almost all other body tissues.”
Public Release: 9-Aug-2015
Common medications could delay brain injury recovery
University of East Anglia
Drugs used to treat common complaints could delay the recovery of brain injury patients according to research led by University of East Anglia (UEA) scientists working with other UK universities including Aston and the NHS, published today in Brain Injury.
Prescribed for up to 50 per cent of older people, medications with anticholinergic properties are used to treat a broad range of common conditions including bladder problems, depression and insomnia.
Anticholinergics are already known to have side effects such as temporary cognitive impairment, dizziness and confusion. But their effects on people with pre-existing brain and spinal injuries have not been investigated until now.
Medications with anti-cholinergic properties are often used on neuro-rehabilitation units frequently to manage symptoms from urinary incontinence to pain.
The study of 52 patients with acquired brain or spinal injury at a neuro-rehabilitation unit showed that the average length of stay was longer in patients with a higher level of anticholinergic drugs in their system, known as the anticholinergic drug burden, or ACB.
Results showed that the change in ACB correlated directly to the length of hospital stay. A higher ACB score on discharge, compared with on admission, was associated with a longer stay in hospital and a lower ACB on discharge saw on average a shorter stay. The team cautioned however that as an observational study, cause-and-effect relationship cannot be implied.
Dr Chris Fox, Professor of Clinical Psychiatry at the Norwich Medical School at UEA and lead author on the paper, said: “The findings suggest there may be a statistically significant relationship between ACB score and length of stay in a neuro-rehabilitation unit following traumatic brain or spinal cord injury”.
He added: “This pilot study demonstrates the need for larger studies to confirm the results and need for further investigation into what long-term effects these common medications are having on the recovery of these patients.”
“While medications with ACB are often needed to treat common complications of brain or spinal cord injuries, cognitive impairment due to the medication may adversely affect a patient’s ability to engage in the rehabilitation process, potentially increasing their length of stay in hospital.”
Length of patient stay is used a performance indicator for hospitals, with financial incentives in place for units to discharge patients as soon as is safe.
Dr Ian Maidment, Senior Lecturer in Clinical Pharmacy at Aston University said: “This work adds to the evidence that anticholinergics should be avoided in a wide-range of populations, when possible. Regular medication review by a nurse, doctor or pharmacist may be a way of ensuring that medicines with anti-cholinergic effects are used appropriately.”
Prof Fox said: “Identifying factors which might adversely affect the length of a patient’s stay can have important financial as well as quality of life implications. So the findings of this study could be directly useful to current health care settings if they can reduce the time patients spend in rehabilitation units, improving wider efficiency of care.”
‘Does anticholinergics drug burden relate to global neuro-disability outcome measures and length of hospital stay?’ is published in the journal Brain Injury on Monday 10 August 2015.
Public Release: 9-Aug-2015
The Lancet Diabetes & Endocrinology: Universal iodine supplementation during pregnancy could offer huge cost savings
The Lancet
Giving all pregnant women iodine supplements, even in mildly iodine deficient countries like the UK, could result in huge cost savings for health care systems and society, according to new modelling research published in The Lancet Diabetes & Endocrinology journal.
The new estimates suggest that introducing iodine supplementation in pregnancy in the UK could save the National Health Service (NHS) around £200 per expectant mother and provide monetary benefits to society of around £4500 per child from increased lifetime earnings and lower public sector costs. With around 1.9 billion people and 241 million school-age children (aged 6-12 years) living in the 32 countries that have iodine deficiency, the authors conclude that the benefits of universal iodine supplementation during pregnancy could be substantial.
“Iodine deficiency in pregnancy remains the leading cause of preventable retardation worldwide. Even mild iodine deficiency during pregnancy is associated with children with lower IQs,” explains Kate Jolly, a co-author and Professor of Public Health at the University of Birmingham in the UK. “It’s time for all women living in iodine deficient countries without universal supplementation of iodine, who are pregnant, breastfeeding, or planning a pregnancy to be advised to take a daily supplement containing iodine.” [1]
Iodine is not made naturally in the body and must be consumed by eating foods like dairy and seafood or supplements. Severe iodine deficiency during pregnancy can cause substantial mental impairment and delayed development in children, resulting in a lower IQ and consequently lower educational attainment and earning potential. International health organisations like WHO and the European Food Safety Authority recommend that pregnant and breastfeeding women take daily iodine supplements. However, no recommendation for iodine supplementation has been issued to pregnant women in the UK, even though mild iodine deficiency has been reported to be widespread.
As a randomised trial might not be approved because of ethical concerns in the untreated group, a team of researchers from the University of Birmingham did a modelling study to examine the cost-effectiveness of iodine supplementation versus no supplementation for pregnant women in the UK. Using data from a systematic review of published studies and expert opinion they modelled both the direct health service savings and monetary benefits to society (lifetime earnings) in terms of gains from an additional IQ point in the children.
By converting the effects of iodine supplementation in pregnancy on developing brains into IQ points, the authors estimate that the benefits equate to 1.22 IQ points per child, with monetary benefits of around £199 per expectant mother for the NHS, and £4476 per pregnancy for society (table 2).
According to the authors, “As food fortification alone may not be enough to achieve iodine sufficiency for pregnant women, our results strengthen the case for universal iodine supplementation of all women before and during pregnancy and whilst breastfeeding in mild-to-moderate iodine deficient countries.” [1]
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NOTES TO EDITORS:
[1] Quotes direct from authors and cannot be found in text of Article.
Public Release: 11-Aug-2015
Chickenpox vaccination does increase shingles cases, but mainly in young adults
Study findings are in favour of universal childhood vaccination
eLife
Vaccinating one-year-olds against chickenpox could temporarily nearly double the incidence of shingles in the wider population, but in younger adults than previously thought.
The effect occurs because vaccination reduces the likelihood of adults who experienced chickenpox as a child being re-exposed to the virus. Re-exposure boosts immunity to shingles, caused by the same virus, Varicella-zoster virus.
In a study to be published in the journal eLife, scientists from the Universities of Antwerp and Hasselt (Belgium) have predicted that the temporary effect of a rise in shingles cases dominates in 31 to 40-year-olds. This is younger than previously predicted and this age group is less at risk of developing the most serious shingles symptoms. Many countries have avoided introducing universal chickenpox vaccination in children because it was previously predicted that the reduction in chickenpox related disease would be outbalanced by the temporarily increase in shingles-related disease.
A new model developed by the scientists also confounds previous findings on the length of time re-exposure chickenpox boosts immunity to shingles. The effect was thought to last for up to 20 years, but results of the current modeling study show it only lasts for two. The new model is the first based on real immunological and virological data from individuals.
“We were surprised to find that re-exposure to chickenpox is beneficial for so few years and also that the most pronounced effect of vaccination on increasing cases of shingles is in younger adults,” says lead author Dr Benson Ogunjimi.
“Our findings should allay some fears about implementing childhood chickenpox vaccination,” he says.
Vaccination programmes are established in some countries including the US, Australia, Greece, Germany, Japan and Taiwan. However, as most – but not all – chickenpox cases are mild, whereas shingles causes a painful rash and can lead to complications such as prolonged pain (postherpetic neuralgia), policy makers in other countries have hesitated to introduce childhood vaccination.
Shingles occurs most often in individuals with a declined immunological status, such as HIV or cancer patients. Ageing is also assumed to increase susceptibility. In previous studies, Ogunjimi and colleagues found that the impact of ageing is exacerbated by Cytomegalovirus infection, another virus in the herpes family.
The current model combines data from individuals relating to all these factors, making it more accurate than previous models and easier to verify with future clinical studies.
“Our new model relates to real biological functions, increasing its value for determining health policy,” says Dr Ogunjimi.
Public Release: 11-Aug-2015
Trans fats, but not saturated fats, linked to greater risk of death and heart disease
Higher trans fat intake associated with 20-30 percent increased risk, say researchers
BMJ
Saturated fats are not associated with an increased risk of death, heart disease, stroke, or type 2 diabetes, finds a study published in The BMJ this week. However, the findings show that trans fats are associated with greater risk of death and coronary heart disease.
The study confirms previous suggestions that industrially produced trans fats might increase the risk of coronary heart disease and calls for a careful review of dietary guidelines for these nutrients.
Guidelines currently recommend that saturated fats are limited to less than 10%, and trans fats to less than 1% of energy to reduce risk of heart disease and stroke.
Saturated fats come mainly from animal products, such as butter, cows’ milk, meat, salmon and egg yolks, and some plant products such as chocolate and palm oils. Trans unsaturated fats (trans fats) are mainly produced industrially from plant oils (a process known as hydrogenation) for use in margarine, snack foods and packaged baked goods.
Contrary to prevailing dietary advice, a recent evidence review found no excess cardiovascular risk associated with intake of saturated fat. In contrast, research suggests that industrial trans fats may increase the risk of coronary heart disease.
To help clarify these controversies, researchers in Canada analysed the results of observational studies assessing the association between saturated and/or trans fats and health outcomes in adults.
Study design and quality were taken into account to minimise bias, and the certainty of associations were assessed using a recognised scoring method.
The team found no clear association between higher intake of saturated fats and all cause mortality, coronary heart disease (CHD), cardiovascular disease (CVD), ischemic stroke or type 2 diabetes, but could not, with confidence, rule out increased risk for CHD death. They did not find evidence that diets higher in saturated fat reduce cardiovascular risk.
However, consumption of industrial trans fats was associated with a 34% increase in all cause mortality, a 28% increased risk of CHD mortality, and a 21% increase in the risk of CHD.
Inconsistencies in the included studies meant that the researchers could not confirm an association between trans fats and type 2 diabetes. And they found no clear association between trans fats and ischemic stroke.
The researchers point out that the certainty of associations between saturated fat and all outcomes was “very low,” which means that further research is very likely to have an important impact on our understanding of the association of saturated fats with disease. The certainty of associations of trans fat with CHD outcomes was “moderate” and “very low” to “low” for other associations.
They also stress that their results are based on observational studies, so no definitive conclusions can be drawn about cause and effect. However, they say their analysis “confirms the findings of five previous systematic reviews of saturated and trans fats and CHD.”
And they conclude that dietary guidelines for saturated and trans fatty acids “must carefully consider the effect of replacement nutrients.”
Public Release: 12-Aug-2015
Protein-packed breakfast prevents body fat gain in overweight teens
High-protein breakfast also improves teens’ glycemic control
University of Missouri-Columbia
COLUMBIA, Mo. (Aug. 12, 2015) Approximately 60 percent of young people habitually skip breakfast up to four times a week, previous research has shown. Although health experts recommend breakfast as a strategy to reduce an individual’s chance of obesity, little research has examined if the actual type of breakfast consumed plays a significant role in one’s health and weight management. University of Missouri researchers compared the benefits of consuming a normal-protein breakfast to a high-protein breakfast and found the high-protein breakfast – which contained 35 grams of protein – prevented gains of body fat, reduced daily food intake and feelings of hunger, and stabilized glucose levels among overweight teens who would normally skip breakfast.
Heather Leidy, Ph.D., an assistant professor in the Department of Nutrition and Exercise Physiology at the MU School of Medicine and lead author of the study, says the key to eating 35 grams of protein is to consume a combination of high-quality proteins including milk, eggs, lean meats and Greek yogurt.
“This study examined if the type of breakfast consumed can improve weight management in young people who habitually skip breakfast,” said Leidy. “Generally, people establish eating behaviors during their teen years. If teens are able to develop good eating habits now, such as eating breakfast, it’s likely to continue the rest of their lives.”
Leidy and her colleagues fed two groups of overweight teens who reported skipping breakfast between five and seven times a week either normal-protein breakfast meals or high-protein breakfast meals. A third group of teens continued to skip breakfast for 12 weeks.
“The group of teens who ate high-protein breakfasts reduced their daily food intake by 400 calories and lost body fat mass, while the groups who ate normal-protein breakfast or continued to skip breakfast gained additional body fat,” Leidy said. “These results show that when individuals eat a high-protein breakfast, they voluntarily consume less food the rest of the day. In addition, teens who ate high-protein breakfast had more stable glucose levels than the other groups.”
Leidy says large fluctuations in glucose levels are associated with an increased risk of Type 2 diabetes among young people, which can make health complications associated with weight gain more intense.
The normal-protein breakfast meal was milk and cereal and contained 13 grams of protein. The high-protein breakfast meals included eggs, dairy and lean pork that contained 35 grams of protein. Participants in the groups were instructed to report feelings of hunger and their daily intakes of food and beverages. Their body weight and body composition were measured at the beginning and end of the 12-week period. In addition, the participants wore a device that assessed minute-to-minute glucose levels throughout the day.
Public Release: 12-Aug-2015
Children who are leaner report eating more polyunsaturated fatty acids
More PUFAs and a higher ratio of PUFA: Saturated fatty acids are included in the self-reported diets of leaner children
University of Colorado Anschutz Medical Campus
AURORA, Colo. (Aug. 12, 2015) – The results of a recent study show that children who report eating more polyunsaturated fatty acids (PUFAs), found in tree nuts, seeds and fatty fish, and consume a higher ratio of PUFA: saturated fatty acids (SFAs), have more lean body mass, lower percent body fat, and less intra-abdominal fat (belly fat).
The study was published in “The Journal of Nutrition” and conducted by researchers at the University of Colorado Anschutz Health and Wellness Center and the University of Colorado School of Medicine at the Anschutz Medical Campus in Aurora, Colo. in collaboration with the University of Alabama at Birmingham.
The study looked at a group of racially diverse children ages 7-12 (39% European-American, 34% African-American, and 27% Hispanic-American). Each child, with parental supervision, provided two separate self-reports of their 24-hour dietary intakes.
“Studies have identified a variety of benefits of including PUFAs into an adult’s diet, particularly omega-3 fatty acids,” said Michelle Cardel, PhD, RD, the study’s lead author. “Our data suggests that consumption of PUFAs is associated with improved body composition in diverse groups of children. It’s important to note, however, that this study was cross-sectional and no causation can be concluded. Randomized experiments are needed to confirm these findings.”
Each child’s body composition and abdominal fat distribution were measured by dual energy x-ray absorptiometry and computed tomography scans, respectively. Those who ate more PUFAs and had a higher ratio of PUFA: SFAs in their reported diet were found to be leaner, have less body fat and less abdominal adiposity.
“Hopefully this work will stimulate additional research to determine if there is a causal relationship between dietary PUFAs, body fat and lean mass in kids,” Cardel said. “Until then, children should consume fatty fish, such as salmon, twice a week to reach Institute of Medicine recommendations for omega-3 fatty acids.”
Cardel is a nutrition scientist and registered dietitian. She plans to continue her research exploring the environmental, behavioral, social, dietary, and genetic factors that influence the development of obesity in diverse groups of children.