Posts Tagged ‘food’


Zinnias such as this one were among the first flowers to be grown on the International Space Station.

Researchers on the International Space Station are growing plants in systems that may one day sustain astronauts traveling far across the solar system and beyond.

Vibrant orange flowers crown a leafy green stem. The plant is surrounded by many just like it, growing in an artificially lit greenhouse about the size of a laboratory vent hood. On Earth, these zinnias, colorful members of the daisy family, probably wouldn’t seem so extraordinary. But these blooms are literally out of this world. Housed on the International Space Station (ISS), orbiting 381 kilometers above Earth, they are among the first flowers grown in space and set the stage for the cultivation of all sorts of plants even farther from humanity’s home planet.

Coaxing this little flower to bloom wasn’t easy, Gioia Massa, a plant biologist at NASA’s Kennedy Space Center in Florida, tells The Scientist. “Microgravity changes the way we grow plants.” With limited gravitational tug on them, plants aren’t sure which way to send their roots or shoots. They can easily dry out, too. In space, air and water don’t mix the way they do on Earth—liquid droplets glom together into large blobs that float about, instead of staying at the roots.

Massa is part of a group of scientists trying to overcome those challenges with a benchtop greenhouse called the Vegetable Production System, or Veggie. The system is a prototype for much larger greenhouses that could one day sustain astronauts on journeys to explore Mars. “As we’re looking to go deeper into space, we’re going to need ways to support astronaut crews nutritionally and cut costs financially,” says Matthew Romeyn, a long-duration food production scientist at Kennedy Space Center. “It’s a lot cheaper to send seeds than prepackaged food.”

In March 2014, Massa and colleagues developed “plant pillows”—small bags with fabric surfaces that contained a bit of soil and fertilizer in which to plant seeds. The bags sat atop a reservoir designed to wick water to the plants’ roots when needed (Open Agriculture, 2:33-41, 2017). At first, the ISS’s pillow-grown zinnias were getting too much water and turning moldy. After the crew ramped up the speed of Veggie’s fans, the flowers started drying out—an issue relayed to the scientists on the ground in 2015 by astronaut Scott Kelly, who took a special interest in the zinnias. Kelly suggested the astronauts water the plants by hand, just like a gardener would on Earth. A little injection of water into the pillows here and there, and the plants perked right up, Massa says.

With the zinnias growing happily, the astronauts began cultivating other flora, including cabbage, lettuce, and microgreens—shoots of salad vegetables—that they used to wrap their burgers and even to make imitation lobster rolls. The gardening helped to boost the astronauts’ diets, and also, anecdotally, brought them joy. “We’re just starting to study the psychological benefits of plants in space,” Massa says, noting that gardening has been shown to relieve stress. “If we’re going to have this opportunity available for longer-term missions, we have to start now.”

The team is currently working to make the greenhouses less dependent on people, as tending to plants during space missions might take astronauts away from more-critical tasks, Massa says. The researchers recently developed Veggie PONDS (Passive Orbital Nutrient Delivery System) with help from Techshot and Tupperware Brands Corporation. This system still uses absorbent mats to wick water to plants’ seeds and roots, but does so more consistently by evenly distributing the moisture. As a result, the crew shouldn’t have to keep such a close eye on the vegetation, and should be able to grow hard-to-cultivate garden plants, such as tomatoes and peppers. Time will tell. NASA sent Veggie PONDS to the ISS this past March, and astronauts are just now starting to compare the new system’s capabilities to those of Veggie.

“What they are doing on the ISS is really neat,” says astronomer Ed Guinan of the University of Pennsylvania. If astronauts are going to venture into deep space and be able to feed themselves, then they need to know how plants grow in environments other than Earth, and which grow best. The projects on the ISS will help answer those questions, he says. Guinan was so inspired by the ISS greenhouses he started his own project in 2017 studying how plants would grow in the soil of Mars—a likely future destination for manned space exploration. He ordered soil with characteristics of Martian dirt and told students in his astrobiology course, “You’re on Mars, there’s a colony there, and it’s your job to feed them.” Most of the students worked to grow nutritious plants, such as kale and other leafy greens, though one tried hops, a key ingredient in beer making. The hops, along with some of the other greens, grew well, Guinan reported at the American Astronomical Society meeting in January.

Yet, if and when astronauts go to Mars, they probably won’t be using the Red Planet’s dirt to grow food, notes Gene Giacomelli, a horticultural engineer at the University of Arizona. There are toxic chemicals called perchlorates to contend with, among other challenges, making it more probable that a Martian greenhouse will operate on hydroponics, similar to the systems being tested on the ISS. “The idea is to simplify things,” says Giacomelli, who has sought to design just such a greenhouse. “If you think about Martian dirt, we know very little about it—so do I trust it is going to be able to feed me, or do I take a system I know will feed me?”

For the past 10 years, Giacomelli has been working with others on a project, conceived by now-deceased business owner Phil Sadler, to build a self-regulating greenhouse that could support a crew of astronauts. This is not a benchtop system like you find on the space station, but a 5.5-meter-long, 2-meter-diameter cylinder that unfurls into an expansive greenhouse with tightly controlled circulation of air and water. The goal of the project, which was suspended in December due to lack of funding, was to show that the lab-size greenhouse could truly sustain astronauts. The greenhouse was only partially successful; the team calculated that a single cylinder would provide plenty of fresh drinking water, but would produce less than half the daily oxygen and calories an astronaut would need to survive a space mission. Though the project is on hold, Giacomelli says he hopes it will one day continue.

This kind of work, both here and on the ISS, is essential to someday sustaining astronauts in deep space, Giacomelli says. And, if researchers can figure out how to make such hydroponic systems efficient and waste-free, he notes, “the heck with Mars and the moon, we could bring that technology back to Earth.”

https://www.the-scientist.com/?articles.view/articleNo/54637/title/Researchers-Grow-Veggies-in-Space/

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Synthetic nanoparticles used to fight cancer could also heal sickly plants.

The particles, called liposomes, are nanosized, spherical pouches that can deliver drugs to specific parts of the body (SN: 12/16/06, p. 398). Now, researchers have filled these tiny care packages with fertilizing nutrients. The new liposomes, described online May 17 in Scientific Reports, soak into plant leaves more easily than naked nutrients. That allows the nanoparticles to give malnourished crops a more potent pick-me-up than the free-floating molecules in ordinary nutrient spray.

Each liposome is a hollow sphere about 100 nanometers across, and is made of fatty molecules extracted from soybean plants. Once a plant leaf absorbs these nanoparticles, the liposomes spread to cells in the plant’s other leaves and its roots, where the fatty envelopes break down and release their molecular cargo.

Researchers first exposed tomato plants to either liposomes packed with a rare earth metal called europium, or free-floating europium molecules. Europium doesn’t naturally exist in plants or soil, so it’s easy to trace how much of this element plants soaked up after treatment. Three days after exposure, plants treated with liposomes had absorbed up to 33 percent of the nanoparticles. Plants exposed to free-floating europium took in less than 0.1 percent of the molecules

The researchers then spritzed iron- and magnesium-deficient tomato plants with either a standard spray containing iron and magnesium, or a solution containing liposomes packed with those nutrients. Two weeks later, the leaves on plants treated with free-floating nutrients were still tinged yellow and curled. Plants that received liposome treatment sported healthy, green leaves.

Avi Schroeder, a chemical engineer at the Israel Institute of Technology in Haifa, and colleagues don’t know exactly why liposomes are more palatable to plants than plain nutrients. But sprays that contain nutrient-loaded liposomes could help farmers rejuvenate frail plants more efficiently than existing mixtures, Schroeder says.

Liposome-based spray would need to be tested on a variety of vegetation before it could enter widespread use, says Ramesh Raliya, a nanobiotechnology researcher at Washington University in St. Louis not involved in the work. That’s because the pores on leaves where liposomes are assumed to enter plants can range from 50 to 150 nanometers across. If a plant’s pores are smaller than 100 nanometers, the liposomes can’t squeeze inside.

Mariya Khodakovskaya, a biologist at the University of Arkansas at Little Rock, is wary of the potential cost of this new technique. Fashioning liposomes is expensive. That’s not a problem for making liposome-based medication, which requires only a small amount of nanoparticles. But for any new agricultural practice to take root, she says, “it has to be massive, and it has to be cheap.”

A. Karny et al. Therapeutic nanoparticles penetrate leaves and deliver nutrients to agricultural crops. Scientific Reports. Published online May 17, 2018. doi: 10.1038/s41598-018-25197-y.

https://www.sciencenews.org/article/nanoparticles-could-help-rescue-malnourished-crops

by Vanessa Zainzinger

Wireless sensors are ubiquitous, providing a steady stream of information on anything from our physical activity to changes occurring in the world’s oceans. Now, scientists have developed a tiny form of the data-gathering tool, designed for an area that has so far escaped its reach: our teeth.

The 2-millimeter-by-2-millimeter devices (pictured) are made up of a film of polymers that detects chemicals in its environment. Sandwiched between two square-shaped gold rings that act as antennas, the sensor can transmit information on what’s going on—or what’s being chewed on—in our mouth to a digital device, such as a smartphone. The type of compound the inner layer detects—salt, for example, or ethanol—determines the spectrum and intensity of the radiofrequency waves that the sensor transmits. Because the sensor uses the ambient radio-frequency signals that are already around us, it doesn’t need a power supply.

The researchers tested their invention on people drinking alcohol, gargling mouthwash, or eating soup. In each case, the sensor was able to detect what the person was consuming by picking up on nutrients.

The devices could help health care and clinical researchers find links between dietary intake and health and, in the long run, allow each of us to keep track of how what we consume is affecting our bodies.

http://www.sciencemag.org/news/2018/03/tiny-sensor-your-tooth-could-help-keep-you-healthy

By Elizabeth Bernstein

You’re feeling depressed. What have you been eating?

Psychiatrists and therapists don’t often ask this question. But a growing body of research over the past decade shows that a healthy diet—high in fruits, vegetables, whole grains, fish and unprocessed lean red meat—can prevent depression. And an unhealthy diet—high in processed and refined foods—increases the risk for the disease in everyone, including children and teens.

Now recent studies show that a healthy diet may not only prevent depression, but could effectively treat it once it’s started.

Researchers, led by epidemiologist Felice Jacka of Australia’s Deakin University, looked at whether improving the diets of people with major depression would help improve their mood. They chose 67 people with depression for the study, some of whom were already being treated with antidepressants, some with psychotherapy, and some with both. Half of these people were given nutritional counseling from a dietitian, who helped them eat healthier. Half were given one-on-one social support—they were paired with someone to chat or play cards with—which is known to help people with depression.

After 12 weeks, the people who improved their diets showed significantly happier moods than those who received social support. And the people who improved their diets the most improved the most. The study was published in January 2017 in BMC Medicine. A second, larger study drew similar conclusions and showed that the boost in mood lasted six months. It was led by researchers at the University of South Australia and published in December 2017 in Nutritional Neuroscience.

And later this month in Los Angeles at the American Academy of Neurology’s annual meeting, researchers from Rush University Medical Center in Chicago will present results from their research that shows that elderly adults who eat vegetables, fruits and whole grains are less likely to develop depression over time.

The findings are spurring the rise of a new field: nutritional psychiatry. Dr. Jacka helped to found the International Society for Nutritional Psychiatry Research in 2013. It held its first conference last summer. She’s also launched Deakin University’s Food & Mood Centre, which is dedicated to researching and developing nutrition-based strategies for brain disorders.

The annual American Psychiatric Association conference has started including presentations on nutrition and psychiatry, including one last year by chef David Bouley on foods that support the peripheral nervous system. And some medical schools, including Columbia University’s Vagelos College of Physicians and Surgeons, are starting to teach psychiatry residents about the importance of diet on mental health.

Depression has many causes—it may be genetic, triggered by a specific event or situation, such as loneliness, or brought on by lifestyle choices. But it’s really about an unhealthy brain, and too often people forget this. “When we think of cardiac health, we think of strengthening an organ, the heart,” says Drew Ramsey, a psychiatrist in New York, assistant clinical professor of psychiatry at Columbia and author of “Eat Complete.” “We need to start thinking of strengthening another organ, the brain, when we think of mental health.”

A bad diet makes depression worse, failing to provide the brain with the variety of nutrients it needs, Dr. Ramsey says. And processed or deep-fried foods often contain trans fats that promote inflammation, believed to be a cause of depression. To give people evidenced-based information, Dr. Ramsey created an e-course called “Eat to Beat Depression.”

A bad diet also affects our microbiome—the trillions of micro-organisms that live in our gut. They make molecules that can alter the production of serotonin, a neurotransmitter found in the brain, says Lisa Mosconi, a neuroscientist, nutritionist and associate director of the Alzheimer’s Prevention Clinic at Weill Cornell Medical College in New York. The good and bad bacteria in our gut have complex ways to communicate with our brain and change our mood, she says. We need to maximize the good bacteria and minimize the bad.

So what should we eat? The research points to a Mediterranean-style diet made up primarily of fruits and vegetables, extra-virgin olive oil, yogurt and cheese, legumes, nuts, seafood, whole grains and small portions of red meat. The complexity of this diet will provide the nutrition our brain needs, regulate our inflammatory response and support the good bacteria in our gut, says Dr. Mosconi, author of “Brain Food: The Surprising Science of Eating for Cognitive Power.”

Can a good diet replace medicine or therapy? Not for everyone. But people at risk for depression should pay attention to the food they eat. “It really doesn’t matter if you need Prozac or not. We know that your brain needs nutrients,” Dr. Ramsey says. A healthy diet may work even when other treatments fail. And at the very least, it can serve as a supplemental treatment—one with no bad side effects, unlike antidepressants—that also has a giant upside. It can prevent other health problems, such as heart disease, obesity and diabetes.

Loretta Go, a 60-year-old mortgage consultant in Ballwin, Mo., suffered from depression for decades. She tried multiple antidepressants and cognitive behavioral therapy, but found little relief from symptoms including insomnia, crying jags and feelings of hopelessness. About five years ago, after her doctor wanted to prescribe yet another antidepressant, she refused the medicine and decided to look for alternative treatments.

Ms. Go began researching depression and learned about the importance of diet. When she read that cashews were effective in reducing depression symptoms, she ordered 100 pounds, stored them in the freezer, and started putting them in all her meals.

She also ditched processed and fried foods, sugar and diet sodas. In their place, she started to eat primarily vegetables and fruits, eggs, turkey and a lot of tofu. She bought a Vitamix blender and started making a smoothie with greens for breakfast each morning.

Within a few months, Ms. Go says she noticed a difference in her mood. She stopped crying all the time. Her insomnia went away and she had more energy. She also began enjoying activities again that she had given up when she was depressed, such as browsing in bookstores and volunteering at the animal shelter.

Ms. Go’s depression has never come back. “This works so well,” she says. “How come nobody else talks about this?”

https://www.wsj.com/articles/the-food-that-helps-battle-depression-1522678367


by Diana Kwon

Findings from a randomized, controlled trial finds that reducing food intake decreases metabolism and reduces oxidative damage to tissues and cells.

Studies in various animals, including rodents and monkeys, have reported that caloric restriction can extend their lifespans. Findings from a two-year, randomized, controlled trial with human participants, published last week (March 22) in Cell Metabolism, suggest that cutting down on calories may also be able to prolong the lives of people.

To investigate the effects of reducing food intake, Leanne Redman, an endocrinologist at the Pennington Biomedical Research Center at Louisiana State University, and her colleagues enrolled 53 healthy men and women between the ages of 21 and 50 and split them into two groups—one group reduced their caloric intake by 15 percent over two years, and the other remained on a regular diet.

The team found that the people who ate a restricted diet lost an average of around 9 kilograms and experienced a 10-percent drop in their resting metabolic rates. When the researchers examined the participants’ blood, they also found a reduction in markers of oxidative stress in those who cut down on calories. “After two years, the lower rate of metabolism and level of calorie restriction was linked to a reduction in oxidative damage to cells and tissues,” Redman tells Wired.

“[I]f by-products of metabolism accelerate aging processes, calorie restriction sustained over several years may help to decrease risk for chronic disease and prolong life,” Redman says in a statement.

This study was part of a larger, multi-center investigation of caloric restriction in humans, the Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy (CALERIE) trial. Luigi Fontana, an internist who ran a CALERIE investigation at Washington University in St. Louis, says that a slower metabolism and reduced oxidative stress will not necessarily lead to a longer life. “You can have a low resting metabolic rate because you’re dying of starvation,” he tells Wired. “Does that make it a biomarker of longevity? No. You can be calorie restricted by eating half a hamburger and a few fries each day but will you live longer? No, you will die of malnutrition.”

https://www.the-scientist.com/?articles.view/articleNo/52141/title/Caloric-Restriction-Slows-Signs-of-Aging-in-Humans/

By Kelsey Gee in Chicago and Julie Wernau in New York

America has built up a glut of cheese so big that every person in the country would need to eat an extra 3 pounds this year to work it off.

And it isn’t just cheese. The growing stacks of cheddar, which can be kept frozen for years, and other cheeses such as feta, which can be stored for only a couple of months, are just the tip of a surplus of U.S. agricultural products that is swamping markets for grains, meat and milk.

Supplies of cheese, meat and poultry started building as farmers decided to expand their herds and flocks two years ago when prices were high and export markets were hot. Abundant stockpiles of grain made it less risky by pushing down feed costs. But the steady climb in the dollar has deterred major foreign buyers, causing supplies to back up in the U.S. just as production is surging to records. That is sending prices for many goods to their lowest levels in years.

“Farmers have had every reason to expand because of strong global demand,” said Shayle Shagam, livestock analyst with the U.S. Department of Agriculture. “But now we have a lot of products looking for a home in a smaller number of places.”

The USDA said last week that stockpiles of soybeans could fall by almost a quarter this year as export demand picks up. Its outlook for other commodity markets wasn’t as bright. Stockpiles of wheat and corn are expected to grow further. Output of red meat and poultry are forecast to climb 3.1% from last year to 97.6 billion pounds, as farmers continue to expand their operations and grow animals to heavier weights, thanks to the cheap grain prices.

The glut of cheese starts with farmers such as Carla Wardin, a 38-year-old who owns the Evergreen Dairy in St. John, Mich., with her husband, Kris. They expanded from 250 to 400 cows and bought a new barn in 2014 when milk prices were soaring. Nobody is making any money now, she said, but producers respond the same way whether prices are low or high.

“You do the exact same thing,” she said. “You milk more cows.”

America’s dairy farmers are expected to produce 212.4 billion pounds of milk this year, the most in history. Much of it is being sold to cheesemakers who are socking away their output, waiting for demand and prices to rise.

The drop in dairy prices this year poses a new test for the industry, which since the 2012 Farm Bill hasn’t had the cushion of U.S. government stockpiling products to support prices.

Commercial cold-storage freezers held a record-breaking 1.19 billion pounds of cheese at the end of March, the latest month for which data is available, up 11% from the same time last year.

Americans eat an average of 36 pounds of cheese a year apiece, but it isn’t enough to keep up. Prices for block cheddar cheese fell to a six-year low of $1.27 a pound Thursday at the Chicago Mercantile Exchange; they have since risen one cent in the spot market.

Scott Meister, a third-generation cheesemaker who owns Meister Cheese Company LLC in Muscoda, Wis., said his company invested millions of dollars to expand its cheese plant in 2014, when prices were above $2 a pound and the company couldn’t keep up with demand. He had planned to dedicate the extra capacity for the production of specialty cheeses such as habanero jack, but is now using that space to boost output of standard cheddar in a bid to soften the blow of lower prices by selling more.

The glut of cheese and other products marks a dramatic turnaround for the animal agricultural sector, which just a few years ago was battling drought and disease that pinched supplies and sent prices at grocery stores to record highs.

Commodities markets frequently swing from boom to bust because of the long lead time for ramping up new supply. Decisions to expand herds of beef and dairy cattle have to be made far in advance, reflecting a cow’s nine-month pregnancy and the year or more it takes for a calf to mature.

“In all commodities, the pendulum swings hard in both directions,” said Justin Reiter, who operates a farm with his dad and brother in Bernard, Iowa, where they grow corn and feed cattle. His family invested $800,000 in a new barn for cattle in 2013, when supplies were tight and the market was starting to pick up steam.

“Now that the chickens have come home to roost, prices have gotten pretty bad,” he said.

C.J. Morton, who handles business development for Iowa-based Des Moines Cold Storage, said the company is preparing by investing $16 million in a new warehouse in the region to store commodities such as pig feet, beef and other proteins.

“If we were more full, it would be impossible to move around” the existing storage space, he said.

The excess supply should mean relief for shoppers. Retail prices for cheese were down 4.3% in April from a year earlier, according to market-research firm IRI. USDA projects consumer beef prices will fall as much as 2% this year, while pork prices could decline by 0.5%.

The industry needs consumers to take advantage of that.

“Someone is going to eat all of this meat and dairy,” said Mr. Shagam, with the USDA. “How much room do you have in your stomach?”

http://www.wsj.com/articles/a-cheese-glut-is-overtaking-america-1463477403

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While researching the brain’s learning and memory system, scientists at Johns Hopkins say they stumbled upon a new type of nerve cell that seems to control feeding behaviors in mice. The finding, they report, adds significant detail to the way brains tell animals when to stop eating and, if confirmed in humans, could lead to new tools for fighting obesity. Details of the study were published by the journal Science today.

“When the type of brain cell we discovered fires and sends off signals, our laboratory mice stop eating soon after,” says Richard Huganir, Ph.D., director of the Department of Neuroscience at the Johns Hopkins University School of Medicine. “The signals seem to tell the mice they’ve had enough.”

Huganir says his team’s discovery grew out of studies of the proteins that strengthen and weaken the intersections, or synapses, between brain cells. These are an important target of research because synapse strength, particularly among cells in the hippocampus and cortex of the brain, is important in learning and memory.

In a search for details about synapse strength, Huganir and graduate student Olof Lagerlöf, M.D., focused on the enzyme OGT — a biological catalyst involved in many bodily functions, including insulin use and sugar chemistry. The enzyme’s job is to add a molecule called N-acetylglucosamine (GlcNAc), a derivative of glucose, to proteins, a phenomenon first discovered in 1984 by Gerald Hart, Ph.D., director of the Johns Hopkins University School of Medicine’s Department of Biological Chemistry and co-leader of the current study. By adding GlcNAc molecules, OGT alters the proteins’ behavior.

To learn about OGT’s role in the brain, Lagerlöf deleted the gene that codes for it from the primary nerve cells of the hippocampus and cortex in adult mice. Even before he looked directly at the impact of the deletion in the rodents’ brains, Lagerlöf reports, he noticed that the mice doubled in weight in just three weeks. It turned out that fat buildup, not muscle mass, was responsible.

When the team monitored the feeding patterns of the mice, they found that those missing OGT ate the same number of meals — on average, 18 a day — as their normal littermates but tarried over the food longer and ate more calories at each meal. When their food intake was restricted to that of a normal lab diet, they no longer gained extra weight, suggesting that the absence of OGT interfered with the animals’ ability to sense when they were full.

“These mice don’t understand that they’ve had enough food, so they keep eating,” says Lagerlöf.

Because the hippocampus and cortex are not known to directly regulate feeding behaviors in rodents or other mammals, the researchers looked for changes elsewhere in the brain, particularly in the hypothalamus, which is known to control body temperature, feeding, sleep and metabolism. There, they found OGT missing from a small subset of nerve cells within a cluster of neurons called the paraventricular nucleus.

Lagerlöf says these cells already were known to send and receive multiple signals related to appetite and food intake. When he looked for changes in the levels of those factors that might be traced to the absence of OGT, he found that most of them were not affected, and the activity of the appetite signals that many other research groups have focused on didn’t seem to be causing the weight gain, he adds.

Next, the team examined the chemical and biological activity of the OGT-negative cells. By measuring the background electrical activity in nonfiring brain cells, the researchers estimated the number of incoming synapses on the cells and found that they were three times as few, compared to normal cells.

“That result suggests that, in these cells, OGT helps maintain synapses,” says Huganir. “The number of synapses on these cells was so low that they probably aren’t receiving enough input to fire. In turn, that suggests that these cells are responsible for sending the message to stop eating.”

To verify this idea, the researchers genetically manipulated the cells in the paraventricular nucleus so that they would add blue light-sensitive proteins to their membranes. When they stimulated the cells with a beam of blue light, the cells fired and sent signals to other parts of the brain, and the mice decreased the amount they ate in a day by about 25 percent.

Finally, because glucose is needed to produce GlcNAc, they thought that glucose levels, which increase after meals, might affect the activity of OGT. Indeed, they found that if they added glucose to nerve cells in petri dishes, the level of proteins with the GlcNAc addition increased in proportion to the amount of glucose in the dishes. And when they looked at cells in the paraventricular nucleus of mice that hadn’t eaten in a while, they saw low levels of GlcNAc-decorated proteins.

“There are still many things about this system that we don’t know,” says Lagerlöf, “but we think that glucose works with OGT in these cells to control ‘portion size’ for the mice. We believe we have found a new receiver of information that directly affects brain activity and feeding behavior, and if our findings bear out in other animals, including people, they may advance the search for drugs or other means of controlling appetites.”

http://www.eurekalert.org/pub_releases/2016-03/jhm-pcc031416.php