About 5 million people in the United States suffer from heart failure (HF). While some reports indicate that changes to diet can reduce HF risk, few large, prospective studies have been conducted. In a new study researchers observed over 14,000 participants for more than 13 years and found that whole grain consumption lowered HF risk, while egg and high-fat dairy consumption raised risk. Other food groups did not directly affect HF risk. The results are published in the November 2008 issue of the Journal of the American Dietetic Association.Diet is among the prominent lifestyle factors that influence major HF risk factors: coronary artery disease, obesity, diabetes and insulin resistance and hypertension. Using data from the Atherosclerosis Risk in Communities (ARIC) study, researchers from the Division of Epidemiology and Community Health, University of Minnesota and the Department of Epidemiology and Cardiovascular Diseases Program, University of North Carolina, analyzed the results of baseline exams of more than 14,000 White and African American adults conducted in 1987-89, with follow-up exams completed during 1990-92, 1993-95, and 1996-98. Four field centers participated in the study: Forsyth County, NC; Jackson, MS; northwest Minneapolis suburbs, MN; and Washington County, MD. The study also collected demographic characteristics and lifestyle factors, as well as other medical conditions such as cardiovascular disease, diabetes and hypertension.

Writing in the article, Jennifer A. Nettleton, Ph.D., states, “Although risk estimates were modest (7% lower risk per 1-serving increase in whole grain intake; 8% greater risk per 1-serving increase in high-fat dairy intake; 23% greater risk per 1-serving increase in egg intake), the totality of literature in this area suggests it would be prudent to recommend that those at high risk of HF increase their intake of whole grains and reduce intake of high-fat dairy and eggs, along with following other healthful dietary practices consistent with those recommended by the American Heart Association.”

A nutritious diet is not seen as being as important as physical activity when it comes to college students’ health and wellness efforts, according to Indiana University researchers, even when the students live in an environment that provides classes, cues and motivation to eat healthily. “Personal preferences triumph over discipline,” the researchers note. The researchers examined the eating habits of college students as they transitioned from high school to university life and to living in residence halls or apartments. Habits that college students establish as they leave home may have long-reaching effects on their health and that of their future families, the researchers note. The students, they say, bring to college the eating habits established at home, where most skipped breakfast and almost 40 percent ate out for dinner or were on their own. This “grab and go” view of food and a preference for restaurant-style foods was apparent in the study. Researchers found that regardless of the variety available in the residence hall or the need to prepare meals in apartment living, foods that can require more preparation or are more perishable are eaten less often. The researchers studied three groups of students — students in apartments, students living in a residence hall and students living in a Fitness and Wellness Living-Learning Center, a themed residential community that provides students with an onsite fitness facility and educational material — including a required course on healthy living. Students in all three groups achieved similar levels of physical activity, with around 56 percent meeting the recommended three bouts of exercise weekly. Compared to how they ate at home, the students reported eating the same amount or less of the healthy foods examined. Students in the Living and Learning Center reported eating even less of these healthy foods. The findings suggest that school and college health educators should consider providing students with tools to “internalize that fitness = exercise = healthy food,” and to find ways for them to eat healthy in our grab-and-go world.

Indiana University researchers studied 730 highly active people, ages 20 to 93, to see how their physical and mental quality of life and rates of obesity-related diseases compare to the general population. Their study participants, United States Master Swimmers, reported swimming regularly for an average of 18.6 years. The percentage of Master Swimmers classified as obese (5.4 percent) and the prevalence of obesity-related diseases such as hypertension (6.5 percent), diabetes (1 percent) and coronary artery disease (1.3 percent), was significantly less than the general population. Their measures of physical and mental quality of life also were significantly better than the general public, with the typical decline in physical quality of life occurring later for them — around the age of 55. Jeanne Johnston, assistant professor in IU’s Department of Kinesiology, said research involving physical activity and obesity-related diseases typically begins by looking at sedentary people and uses this population to establish baseline data, rather than examining active people who could represent model behavior. “The low incidence of overweight and obesity as well as the self-reported diseases demonstrates that active engagement in physical activity improves both physical and mental health as well as the diseases people might have,” she said. Examining highly active people, Johnston and her colleagues wrote, might lead to a better understanding of the relationship between lifelong physical activity, successful aging, morbidity and quality of life.

People taking care of more than one generation — such as their children and parents — engaged in fewer healthy behaviors, found a study by researchers from Indiana University and Arizona State University. As the U.S. population continues to age, more and more midlife adults find themselves similarly “sandwiched,” leading the research team to conclude that “encouraging healthy behaviors among caregivers has the potential to prevent significant illness and premature mortality.” The study involved 4,943 participants in a longitudinal study who reported the number of hours per week they spent caring for their children, parents and in-laws. The researchers looked at five health behaviors: checking food labels for health value when buying foods, using a seat belt, choosing foods based on health value, exercising regularly and cigarette smoking. Compared with people caring for a single generation, people in the sandwich generation were less likely to check food labels, wear seat belts or choose foods based on health values. They also smoked more cigarettes each day.

Even though the U. S. Environmental Protection Agency (EPA) has given final approval for use of a new pesticide, regulators in California and other states are taking a closer look at the substance’s potential adverse health effects before allowing the chemical to be used, according to an article scheduled for the Oct. 27 issue of Chemical & Engineering News, ACS’ weekly newsmagazine.

In the article, C&EN Associate Editor Britt E. Erickson notes that EPA first considered approving the pesticide, methyl iodide, in 2006 as a replacement for methyl bromide —which is now being phased out because of environmental concerns that it may damage the ozone layer. Although methyl iodide appears unlikely to have that effect, it is toxic to nerve cells and may carry a risk of thyroid damage, cancer, and other adverse health effects.

At least one environmental group and some scientists opposed EPA’s approval of the pesticide, alleging that EPA had been secretive during the review process, failing to fully consider the chemical’s health effects, and they pointed to an apparent conflict of interest involving the pesticide’s manufacturer. States like California and Florida had their own concerns about the pesticide’s safety and decided to do their own risk assessments before allowing use of methyl iodide. Florida finished its assessment and approved the use of methyl iodide last July, but not before requiring additional safety measures beyond those required by EPA. California’s assessment is still ongoing, the article notes.

Scientists are reporting development of a device that could serve as the electronic “reader” for a coming generation of “wellness cards,” specimen holders used to diagnose disease from a drop of a patient’s saliva or blood. The research, done by scientists in Utah, Iowa, Arizona, and Minnesota, is presented in two papers scheduled for the November 1 issue of ACS’ Analytical Chemistry, a semi-monthly journal.

In those studies, Marc Porter and colleagues describe using the same technology at the heart of miniaturized hard disk drives to create the new rapid-screening sensor. Using a phenomenon known as giant magnetoresistance (GMR), the device can detect samples on much smaller areas compared to older technologies, the papers note.

As a test, Porter demonstrated the GMR sensor could detect as few as 800 magnetic beads with microscopic dimensions. “Several laboratories have begun to transition GMRs from the data storage domain to that of the bioanalytical sciences,” the paper states. “We believe that, by leveraging advances made in the magnetic recording industry (for example portable digital music players), a robust, field-deployable, assay device capable of sensing single-binding events is just over the horizon.”

New research continues to link tart cherries, one of today’s hottest “Super Fruits,” to lowering risk factors for heart disease. In addition to lowering cholesterol and reducing inflammation, the study being presented by University of Michigan researchers at next week’s American Dietetic Association annual meeting, found that a cherry-enriched diet lowered body weight and fat – major risk factors for heart disease.In the study, at-risk, obese rats that were fed a cherry-enriched diet saw significant decreases in body weight and fat (especially the important “belly” fat with known risk for heart disease) while maintaining lean muscle mass. After twelve weeks, the cherry-fed rats had 14 percent lower body fat compared to the other rats who did not consume cherries (cherry-fed rats were approximately 54% body fat; rats eating the Western diet alone were 63% body fat). The researchers suggested cherry consumption could have an effect on important fat genes and genetic expression. According to the American Heart Association, being overweight or obese, in particular when the weight is concentrated in the middle, is a major risk factor for heart disease . Nearly two out of three Americans are overweight.

The animals were fed a “Western diet,” characterized by high fat and moderate carbohydrate – in line with the typical American diet – with or without added whole tart cherry powder, as 1 percent of the diet. The study was funded by the Cherry Marketing Institute, which provided an unrestricted grant to the University of Michigan to conduct the research and was not directly involved in the design, conduct or analysis of the project.

“Heart disease is the number one killer of Americans today, so it’s important we continue researching ways people can improve their diet to help reduce key risk factors,” said study co-author Dr. Steven F. Bolling, a cardiac surgeon at the University of Michigan Cardiovascular Center who also heads the U-M Cardioprotection Research Laboratory, where the study was performed. “We know excess body fat increases the risk for heart disease. This research gives us one more support point suggesting that diet changes, such as including cherries, could potentially lower heart disease risk.”

Cherry-enriched diets in the study also reduced total cholesterol levels by about 11 percent and two known markers of inflammation – commonly produced by abdominal fat and linked to increased risk for heart disease. Inflammation marker TNF-alpha was reduced by 40 percent and interleukin 6 (IL-6) was lowered by 31 percent. In their genetic analysis, the researchers found that the cherry-enriched diets reduced the genes for these two inflammation compounds, suggesting a direct anti-inflammation effect. While inflammation is a normal process the body uses to fight off infection or injury, according to recent science, a chronic state of inflammation could increase the risk for diseases and may be especially common for those who are overweight or obese, at least in part because of excess weight around the middle. Researchers say the animal study is encouraging and will lead to further clinical studies in humans to explore the link between diet, weight, inflammation and lowering heart disease risk.

The Power of Eating Red

Tart cherries, frequently sold as dried, frozen or juice, contain powerful antioxidants known as anthocyanins, which provide the bright, rich red color. Studies suggest these colorful plant compounds may be responsible for cherries’ anti-inflammatory properties and other health benefits.

This new research is the latest linking this red hot “Super Fruit” to protection against heart disease and inflammation. In fact, research suggests the red compounds in cherries that deliver the anti-inflammatory benefits may also help ease the pain of arthritis and gout.

Children are exposed to a wide range of environmental threats that can affect their health and development early in life, throughout their youth and into adulthood. Writing in a forthcoming issue of the International Journal of Environmental Health scientists from the World Health Organization and Boston University suggest that it is time for both industrialized and developing countries to assess the environmental burden of childhood diseases with the aim of improving children’s environments.

Maria Neira, Fiona Gore, Marie-Noël Bruné, and Jenny Pronczuk de Garbino of the Department of Public Health and Environment, at the World Health Organization, in Geneva, Switzerland, working with Tom Hudson of Boston University, highlight a recent WHO report that estimated that almost one in four illnesses has an environmental cause. Such high levels of disease kill more than ten million children each year and are, the team says, unacceptable.

They point out that environmental hazards are multiplying and becoming more visible because of environmental change, rapid population growth, overcrowding, and the speedy industrialization uncontrolled pollution of many regions. Those environmental factors that have the greatest disease burden lead to diarrheal diseases, lower respiratory infections and malaria, as well as malnutrition, poisonings, and perinatal conditions.

Work must now be done, they stress, to distinguish the main environmental threats affecting children’s health so that nations can identify the various factors and address them through remediation and education through better-informed policy-making decisions. Factors such as polluted indoor and outdoor air, contaminated water and lack of adequate sanitation, chemical and other toxic hazards, disease vectors, ultraviolet radiation and degraded ecosystems are all important environmental risk factors affecting children around the world.

It is crucial to recognize that children are more vulnerable than adults to environmental risks because they are generally constantly growing and more active and so breathe more air, consume more food and drink more water weight for weight than adults. The child’s developing central nervous, immune, reproductive, and digestive systems, are also more susceptible to irreversible damage from toxins and pollutants.

They also point out that two other important factors affect the environmental risks experienced by children differently from adults. First, children play and crawl on the ground where they are exposed to dust and chemicals that accumulate on floors and soils. Secondly, they have far less control over their environment than adults have and are usually less aware of risks and unable to make choices to protect their health.

The team hopes that taking action to address all such issues will ultimately reduce the burden of disease affecting children globally and so contribute towards the Millennium Development Goals (MDGs).

Over-the-counter mouthrinses really do put a stop to bad breath.  The first systematic review on the effectiveness of mouthrinses shows that they play an important role in reducing levels of bacteria and chemicals that cause mouth odours.  Pick which one you use though, because some can temporarily stain your tongue and teeth, warns this new review from The Cochrane Library.

Bad breath is a very common complaint affecting around half the population in developed countries.  The smell is generated by bacteria that accumulate on the tongue and produce sulphur compounds including hydrogen sulphide.  This is the same compound that makes rotten eggs smell bad.  To combat this, mouth rinses are classified in two categories, those that kill the bacteria producing the sulphur compounds and those that neutralise or mask the odour of these compounds.  Antibacterial mouthrinses are widely used to treat bad breath, despite some uncertainty about their effectiveness.

“We found that antibacterial mouthrinses, as well as those containing chemicals that neutralise odours, are actually very good at controlling bad breath,’ says lead researcher, Zbys Fedorowicz, who works at the Ministry of Health in Bahrain.

Although the different mouthrinses had similar effects on odours, the researchers point out that products containing chlorhexidine resulted in noticeable but temporary staining of the tongue and teeth, and also can temporarily alter taste sensations.

The review, carried out by a team of Cochrane Researchers, included the results of five separate trials involving 293 participants.  The team found that mouthrinses employing antibacterial agents such as chlorhexidine and cetylpyridinium were significantly more effective than placebos in reducing mouth odours, as judged by human noses.  Mouthrinses containing chlorine dioxide and zinc were more effective in neutralising odour compounds.

Researchers also noted that more studies are needed to compare the effectiveness of different mouthrinses in treating bad breath.  And they say that despite the growing trend for electronic assessment of mouth odours, the human nose should remain the gold standard.

“There’s no substitute for a human nose when it comes to sniffing out bad breath,” says Fedorowicz.

Moderate consumption of red wine may decrease the risk of lung cancer in men, according to a report in the October issue of Cancer Epidemiology, Biomarkers & Prevention¸ a journal of the American Association for Cancer Research.

“An antioxidant component in red wine may be protective of lung cancer, particularly among smokers,” said Chun Chao, Ph.D., a research scientist at Kaiser Permanente Department of Research and Evaluation in Pasadena, California.

Chao analyzed data collected through the California Men’s Health Study, which linked clinical data from California’s health system with self-reported data from 84,170 men aged 45 to 69 years. Researchers obtained demographics and lifestyle data from surveys computed between 2000 and 2003, and identified 210 cases of lung cancer.

Researchers measured the effect of beer, red wine, white wine and liquor consumption on the risk of lung cancer. Adjustments were made for age, race/ethnicity, education, income, body mass index, history of chronic obstructive pulmonary disease or emphysema, and smoking history.

Among the study participants, there was on average a two percent lower lung cancer risk associated with each glass of red wine consumed per month. The most substantial risk reduction was among smokers who drank one to two glasses of red wine per day. The researchers reported a 60 percent reduced lung cancer risk in these men. Researchers warned men to stop smoking as the best way to reduce lung cancer risk; noting that even men who drank one to two glasses of red wine per day still face higher lung cancer risk than do non-smokers.

No clear associations with lung cancer were noted for consumption of white wine, beer, or liquor. “Red wine is known to contain high levels of antioxidants. There is a compound called resveratrol that is very rich in red wine because it is derived from the grape skin. This compound has shown significant health benefits in preclinical studies,” Chao said.

Chao said their findings should not be construed to recommend heavy alcohol consumption.

A fatty acid found in abundance in olive oil and other “healthy” unsaturated fats has yet another benefit: it helps keep the body satisfied to prolong the time between meals.

A new study in the October Cell Metabolism, a publication of Cell Press, reveals that once this type of fat, known as oleic acid, reaches the intestine, it is converted into a lipid hormone (oleoylethanolamide, or OEA) that wards off the next round of hunger pangs.  The researchers said it may be the first description of an ingredient in food that directly provides the raw materials for a hormone’s production.

The findings in rats may yield insight into the precise dietary makeup of fat and protein for optimal hunger control, the researchers said.  (Protein plays in important role in limiting hunger as well, but by different means.)  The newly discovered signaling pathway might also be tapped into with drugs designed to control appetite by supplementing OEA levels or blocking its breakdown.  Similarly, in conditions where people don’t eat enough, the researchers speculate that treatments targeting this system might improve the appetite.

Importantly, diets high in processed foods that are riddled with saturated fats might throw a wrench into this system of metabolic control, the researchers said.

” Eating is one of the most important things animals do,” said Daniele Piomelli of the University of California, Irvine.  “This is just one of many things that control it.  That said, a system like this could be forced to inactivation by inappropriate feeding,” he said, noting that saturated fats generally lack in oleic acid.

While such diets may lead people to overeat, Piomelli said it will also be of interest to see if this mechanism may be defective in some who tend to eat in excess.

Previous studies had shown that feeding stimulates cells in the intestinal lining to produce OEA, which, when administered as a drug, decreases meal frequency by engaging receptors called peroxisome proliferator-activated receptors a (PPARa).

Piomelli’s team now reports that infusion of fat into the small intestine stimulates the release of OEA, whereas infusion of protein or carbohydrate does not.  They also demonstrate that OEA production uses dietary oleic acid and is disrupted in mutant mice lacking the membrane fatty-acid transporter CD36.  Treatments that disrupt CD36 or PPARa undermine the hunger control otherwise driven by fat.

Overall, the results suggest that activation of small-intestinal OEA release, enabled by CD36-mediated uptake of oleic acid from the diet, serves as a molecular sensor linking fat consumption to satiety.  (Piomelli said satiety is perhaps best described as the opposite of hunger.)

” In conclusion,” the researchers wrote, “our studies identify OEA as a key physiological signal that specifically links dietary fat ingestion to across-meal satiety.  Nutritional and pharmacological strategies aimed at magnifying this lipid-sensing mechanism, such as inhibitors of OEA degradation, might be useful in the treatment of obesity and other eating disorders.”

A Brazilian palm berry sweeping the globe as a popular health food though little research has been done on it – now may have its purported benefits better understood.

In the first research involving people, the acai (ah-sigh-EE) berry has proven its ability to be absorbed in the human body when consumed both as juice and pulp.  That finding, by a team of Texas AgriLife Research scientists, was published in a recent issue of the Journal of Agricultural and Food Chemistry.

Showing the berry’s absorption in humans is important because it is known to contain numerous antioxidants.  The berry is heavily marketed in the U.S. as a health food.

The study involved 12 healthy volunteers who consumed a single serving of acai juice or pulp.  Researchers believe the results point to the need for continued research on the berry which is commonly used in juices, beverages, smoothies, frozen treats and dietary supplements.

“Acai is naturally low in sugar, and the flavor is described as a mixture of red wine and chocolate,” said lead investigator Dr. Susanne Talcott, “so what more would you want from a fruit?”

Talcott, who also is assistant professor with the Texas A&M University’s nutrition and food science department, said that previous studies have shown the ability of the human body to absorb target antioxidants (from other produce), but “no one had really tested to see if acai antioxidants are absorbed in humans.”

Sales of acai products have increased dramatically in the U.S. where it has been touted as a metabolism booster, weight reducer and athletic enhancer.  Advertisements use buzzwords such as health, wellness, energy, taste and organic.

About the only buzzword not used with acai is “local.”  The berries are harvested in the Brazilian rainforest from acai palms that may reach heights in excess of 60 feet one of the same palms used to harvest edible hearts of palm.

The fruit is about the size of a large blueberry yet only the outermost layers of the fruit, the pulp surrounding a large internal seed, are edible, Talcott noted.

Talcott and her co-researcher and husband Dr. Steve Talcott began studying the palmberry in 2001.  His first scientific report on acai, apparently the first such study in English, was published in 2004.

Initially, their studies on the berry examined antioxidant and nutritional components in pulp and juice.  Later studies showed the berry’s activity against cancer cells, Talcott noted.

With that background, the researchers then decided to find out whether those elements were actually being absorbed into the human body or being eliminated unused as waste.

“Like vitamin C, the body can only absorb so much at a time,” Steve Talcott explained.

He said the researchers now “need to determine potential disease-fighting health benefits, so we can make intelligent recommendations on how much acai should be consumed.

For the clinical trial, people were given acai pulp and acai juice containing half the concentration of anthocyanins as the pulp and each compared to the control foods: applesauce and a non-antioxidant beverage.

Blood and urine samples at 12 and 24 hours after consumption showed significant increases in antioxidant activity in the blood after both the acai pulp and applesauce consumption, she said.  Both acai pulp and acai juice showed significant absorption of antioxidant anthocyanins into the blood and antioxidant effects.  The research couple said future studies hopefully will help determine whether the consumption of acai will result in any disease-preventing health benefit and the proper serving sizes for a beneficial dose for people.

“Our concern has been that it is sold as a super food – and it definitely has some good attributes – but it is not a solution to all diseases,” she said.  “There are a great number of foods on the market, and this could just be part of a well-balanced diet.”

Chemicals used in the environment to kill bacteria could be making them stronger, according to a paper published in the October issue of the journal Microbiology.  Low levels of these chemicals, called biocides, can make the potentially lethal bacterium Staphylococcus aureus remove toxic chemicals from the cell even more efficiently, potentially making it resistant to being killed by some antibiotics.

Biocides are used in disinfectants and antiseptics to kill microbes.  They are commonly used in cleaning hospitals and home environments, sterilizing medical equipment and decontaminating skin before surgery.  At the correct strength, biocides kill bacteria and other microbes.  However, if lower levels are used the bacteria can survive and become resistant to treatment.

“Bacteria like Staphylococcus aureus make proteins that pump many different toxic chemicals out of the cell to interfere with their antibacterial effects,” said Dr Glenn Kaatz from the Department of Veterans Affairs Medical Center in Detroit, USA.  “These efflux pumps can remove antibiotics from the cell and have been shown to make bacteria resistant to those drugs.  We wanted to find out if exposure to biocides could also make bacteria resistant to being killed by the action of efflux pumps.”

The researchers exposed S. aureus taken from the blood of patients to low concentrations of several biocides and dyes, which are also used frequently in hospitals.  They looked at the effect of exposure on the bacteria and found that mutants that make more efflux pumps than normal were produced.

“We found that exposure to low concentrations of a variety of biocides and dyes resulted in the appearance of resistant mutants,” said Dr Kaatz.  “The number of efflux pumps in the bacteria increased.  Because the efflux pumps can also rid the cell of some antibiotics, pathogenic bacteria with more pumps are a threat to patients as they could be more resistant to treatment.”

If bacteria that live in protected environments are exposed to biocides repeatedly, for example during cleaning, they can build up resistance to disinfectants and antibiotics.  Such bacteria have been shown to contribute to hospital-acquired infections.

“Scientists are trying to develop inhibitors of efflux pumps.  Effective inhibitors would reduce the likelihood of additional resistance mechanisms emerging in bacteria,” said Dr Kaatz.  “Unfortunately, inhibitors evaluated to date do not work on a wide range of pathogens so they are not ideal to prevent resistance.”

“Careful use of antibiotics and the use of biocides that are not known to be recognised by efflux pumps may reduce the frequency at which resistant strains are found,” said Dr Kaatz.  “Alternatively, the combination of a pump inhibitor with an antimicrobial agent or biocide will reduce the emergence of such strains and their clinical impact.”

If the current financial climate has taught us anything, it’s that a system where over-borrowing goes unchecked eventually ends in disaster.  It turns out this rule applies as much to our bodies as it does to economics.  Instead of cash, our body deals in energy borrowed from muscle and given to the brain.

Unlike freewheeling financial markets, the lending process in the body is under strict regulation to ensure that more isn’t lent than can be afforded.  New research by scientists at the Salk Institute for Biological Studies reveals just how this process is implemented.

“We have all seen the sub-prime mortgage crisis,” says Marc Montminy, M.D., Ph.D., a professor in the Clayton Foundation Laboratories for Peptide Biology who led the current study.  “If you take out a loan, sooner or later you’ve got to pay your debt, and the same is true in fasting metabolism.”

The Salk researchers’ findings, which are published ahead of print in the Oct. 5 edition of the journal Nature, may pave the way for novel therapies for sufferers of metabolic diseases in whom such regulation can spiral out of control.

Most tissues in our bodies respond to fasting by switching from their usual high-octane energy source—glucose—to burning a low-octane, cheaper alternative-fat.  For our brains, however, only the high-performance fuel will do.  If no food-derived glucose is available, the body must manufacture its own supply to maintain the brain in the manner to which it is accustomed.  It does so by taking energy from muscle in the form of protein and converting it to glucose in the liver, a process known as gluconeogenesis.  The sugar is then shipped via the bloodstream to the brain to keep it running smoothly.

Gluconeogenesis needs to be turned on rapidly in response to fasting, but shutting it off again is just as crucial.  “You don’t want gluconeogenesis to be prolonged,” says postdoctoral researcher and co-first author Yi Liu, Ph.D. “Because it uses muscle as a protein source, it will eventually lead to muscle wastage.”  Adds Montminy, “The question has always been how is the production of glucose turned on, and how is shut off again?”

Previous work by the Montminy lab and others has shown that two key proteins, CRTC2 and FOXO1, are needed to turn on glucose-making genes during fasting.  CRTC2 is activated by glucagon, a hormone whose levels go up when we stop eating.  FOXO1, on the other hand, is activated when levels of the food-stimulated hormone insulin drop below a certain threshold.  CRTC2’s and FOXO1’s activity needs to be tightly regulated, since producing too much glucose would result in over-borrowing of energy from muscle tissue.

To uncover the mechanism that ensures that this doesn’t happen, the Salk researchers created mice containing the gene for luciferase, a light-emitting enzyme usually found in fireflies, engineered in such a way that it was only turned on when CRTC2 was active.  Using imaging equipment, they could then detect CRTC2 activity in the livers of live mice simply by measuring how much they glowed.

When the mice were fasted, CRTC2 was rapidly activated, and the livers lit up, but to the scientists’ surprise, after six hours the light went out.  Experimentally decreasing the levels of CRTC2 or FOXO1 confirmed there was a two-stage fasting-response.  Lowering CRTC2 reduced gluconeogenesis only early on, while less FOXO1 only affected late glucose production.  As in a relay race, during fasting the baton for glucose production appeared to be passed from CRTC2 in stage one to FOXO1 in stage two.

The crucial switch from CRTC2 to FOXO1 comes in the form of SIRT1, a nutrient sensor that accumulates in the late fasting stage.  Yi discovered that SIRT1 has opposite effects on CRTC2 and FOXO1: it sends the former to the recycling bin, while it activates the latter, and thus the baton is safely transferred from CRTC2 to the FOXO1.

Why does the body want to change between these two regulators of glucose production?  Again, it comes down to body economics.  CRTC2 acts as a rapid response unit to quickly produce high levels of glucose when it detects glucagon.  Switching to FOXO1 later on slows down this production to more sustainable levels, while at the same time helping to produce ketone bodies, an alternative fuel the brain can use that does not require taking protein from muscle.  “It is just like paying your loan back,” says Montminy.  “Later on you produce blood sugar at a different rate than you did at the beginning.”

Knowledge of how this nutrient switch is working may help design new drugs to regulate sugar levels in diabetes patients.  In, particular, chemical activators of the SIRT1 switch may be key.  “This way we could provide control for patients with insulin resistance,” says Montminy, “as typically their blood sugars are elevated after overnight fasting because the switches that regulate the glucose-producing enzymes are too active.”  Perhaps, then, a pharmacological rescue package for patients whose lending systems have been left unregulated may be on the horizon.

Exposure to Bisphenol A (BPA), phthalates and flame retardants (PBDEs) are strongly associated with adverse health effects on humans and laboratory animals.  A special section in the October 2008 issue of Environmental Research, “A Plastic World” provides critical new research on environmental contaminants and adverse reproductive and behavioral effects.

Plastic products contain “endocrine disrupting chemicals” that can block the production of the male sex hormone testosterone (phthalates used in PVC plastic), mimic the action of the sex hormone estrogen (bisphenol A or BPA used in polycarbonate plastic), and interfere with thyroid hormone (brominated flame retardants or PBDEs used in many types of plastic).

Two articles report very similar changes in male reproductive organs in rats and humans related to fetal exposure to phthalates.  Two articles show that fetal exposure to BPA or PBDEs disrupts normal development of the brain and behavior in rats and mice.  Two other articles provide data that these chemicals are massively contaminating the oceans and causing harm to aquatic wildlife.

The other studies integrate new laboratory research with a broader view reflecting exposures to a variety of chemicals in plastic.  These ubiquitous chemicals found in many plastics act independently and together to adversely affect human, animal and environmental health.

The articles show amongst others the massive contamination of the Pacific Ocean with plastic, and the amount of contamination has increased dramatically in recent years; animal brain structure, brain chemistry and behavioral effects from exposure to BPA and “phthalate syndrome” in rats’ male offspring.

“For the first time a series of articles will appear together that identify that billions of kilograms of a number of chemicals used in the manufacture of different types of plastic can leach out of plastic products and cause harm to the brain and reproductive system when exposure occurs during fetal life or prior to weaning,” emphasized Dr. Frederick vom Saal, Guest Editor of the “Plastic World”.

“Not only are these studies of scientific importance, they also contribute to the ongoing US congressional hearings involving the Food and Drug Administration,” remarked Gert-Jan Geraeds, Publisher of Environmental Research, “As such, “The Plastic World” has a broader societal impact and raises awareness of increasingly important environmental issues”.