Ancient sea reptile with gammy jaw suggests dinosaurs got arthritis too
ScienceDaily (May 15, 2012) Imagine having arthritis in your jaw bones … if they’re over 2 meters long! A new study by scientists at the University of Bristol has found signs of a degenerative condition similar to human arthritis in the jaw of a pliosaur, an ancient sea reptile that lived 150 million years ago. Such a disease has never been described before in fossilized Jurassic reptiles.
The Bristol scientists studied a giant specimen of the pliosaur Pliosaurus dating from the Upper Jurassic. Found in Westbury, Wiltshire, it has been kept since its discovery in the collections of the Bristol City Museum and Art Gallery.
The 8 metre long pliosaur was a terrifying creature with a large, crocodile-like head, a short neck, whale-like body and four powerful flippers to propel it through water in pursuit of prey.
With its huge jaws and 20 cm long teeth, it would have been capable of ripping most other marine reptiles or dinosaurs to pieces, but this particular individual was the unfortunate victim of an arthritis-like disease.
University of Bristol scientist, Dr Judyth Sassoon, was fascinated by the specimen when she saw it in the museum’s collections and studied it for her MSc research project.
She soon noticed that it had the signs of a degenerative condition similar to human arthritis, that had eroded its left jaw joint, displacing the lower jaw to one side. This animal evidently lived with a crooked jaw for many years, because there are marks on the bone of the lower jaw where the teeth from the upper jaw impacted on the bone during feeding. Clearly the animal was still able to hunt in spite of its unfortunate condition.
There are several signs on the skeleton to suggest that the animal could have been an old female who had developed the condition as part of the aging process. The pliosaur’s large size, and the fused skull bones, suggest maturity. It is identified, very tentatively, as possibly female because its skull crest is quite low — presumed males had a higher crest.
Dr Judyth Sassoon said: “In the same way that aging humans develop arthritic hips, this old lady developed an arthritic jaw, and survived with her disability for some time. But an unhealed fracture on the jaw indicates that at some time the jaw weakened and eventually broke. With a broken jaw, the pliosaur would not have been able to feed and that final accident probably led to her demise.”
Pliosaurs were probably pursuit or ambush predators, feeding on fish, squid and other marine reptiles but would also have been capable of scavenging. They were at the top of their food chains, so there would not have been any predators to take advantage of an aging, disabled pliosaur — except for another pliosaur.
Professor Mike Benton, a collaborator on the project, said: “You can see these kinds of deformities in living animals, such as crocodiles or sperm whales and these animals can survive for years as long as they are still able to feed. But it must be painful. Remember that the fictional whale, Moby Dick from Herman Melville’s novel, was supposed to have had a crooked jaw!”
The pliosaur from Westbury is an amazing example of how the study of disease (palaeopathologies) in fossil animals can help us to reconstruct an extinct animal’s life history and behavior and to show that even a Jurassic killer could succumb to the diseases of old age.
The research was published May 16 in the palaeontological journal, Palaeontology.
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Article source: http://www.sciencedaily.com/releases/2012/05/120515203019.htm
Hidden lives of elephant seals: Record-setting dive more than a mile deep
ScienceDaily (May 15, 2012) Researchers at the University of California, Santa Cruz, who pioneered the use of satellite tags to monitor the migrations of elephant seals have compiled one of the largest datasets available for any marine mammal species, revealing their movements and diving behavior at sea in unprecedented detail.
A new study published May 15 in the journal PLoS ONE focuses on the annual migrations of adult female elephant seals, with data from nearly 300 animals. The results show elephant seals traveling throughout the entire northeast Pacific Ocean on foraging trips in search of prey such as fish and squid.
“This work is unprecedented in terms of the number of animals tracked. For the first time we can truly say that we know what the elephant seal population is doing,” said Daniel Costa, professor of ecology and evolutionary biology and leader of the elephant seal research group at UC Santa Cruz. “This represents the efforts of a large number of graduate students, postdoctoral researchers, and undergraduate volunteers who have all worked very hard to make this happen.”
The researchers found that individual seals pursue a variety of different foraging strategies, but most of them target one oceanographic feature in particular–a boundary zone between two large rotating ocean currents, or gyres. Along this boundary, the cold nutrient-rich waters of the sub-polar gyre in the north mix with the warmer waters of the subtropical gyre, driving the growth of phytoplankton and supporting a robust food web. Presumably, this leads to a concentration of prey along the boundary, said Patrick Robinson, a postdoctoral researcher in Costa’s lab and lead author of the paper.
“The highest density of seals is right over that area, so something interesting is definitely going on there,” Robinson said.
Previous studies by Costa and other participants in the Tagging of Pacific Predators program have shown that this boundary zone is important for a wide range of marine predators, including elephant seals, sharks, tuna, and albatrosses. A surface feature associated with the boundary zone, caused by blooms of phytoplankton, is detectable in satellite images, but it moves seasonally as much as 1,000 kilometers to the south. The deep-diving elephant seals do not follow this surface feature, but continue to target the deep boundary zone between the two gyres.
Smaller numbers of female elephant seals feed in coastal regions, pursuing bottom-dwelling prey along the continental shelf, or in other areas outside of the boundary zone such as around seamounts. Among these is a large female that feeds near Vancouver Island and holds the record for deepest recorded dive by an elephant seal. The data analyzed in the PLoS ONE paper include one dive to 1,747 meters (5,765 feet, well over a mile), and the same seal dove even deeper on a more recent foraging trip, reaching 1,754 meters (5,788 feet), Robinson said.
Female northern elephant seals make two foraging trips every year. After the breeding season in February and March, they head out to sea for two months before returning to the rookery to molt. Then they leave on a long post-molting migration that often lasts eight months, from June to January. The amount of food a female is able to find on these foraging trips directly affects her breeding success and, if she gives birth, her pup’s growth rate and chances of survival.
“If foraging is not good, the pups are smaller at weaning because the females produce less milk,” Robinson said.
In addition to tracking the foraging migrations, the researchers monitor the health of the seals and track birth rates over time. Tags are attached harmlessly onto the animals’ fur and recovered when they return to the rookery. Before and after each migration, the researchers get weights and blood samples from the tagged seals, which always return to the same rookery. The tags used today are far more sophisticated than the first ones deployed by UCSC researchers in the 1980s. Current devices, used on a subset of the seals in this study, can capture an animal’s location, swim speed, and depth and duration of dives, as well as the temperature and salinity of the seawater and how that changes with depth.
Most of the animals in this study were tagged at the rookery on Año Nuevo Island, where UCSC researchers have been studying elephant seals for decades. But the study also involved a collaboration with researchers in Mexico to tag elephant seals at Islas San Benito, which is 1,150 kilometers (690 miles) southeast of Año Nuevo. “A lot of those animals travel much further to get to foraging areas in the north, so they might spend an extra week traveling, and we wanted to see how that affects them,” Robinson said. “The animals from San Benito that do go up to feed at the boundary zone do fine, but we also found that many of them stayed closer to home, feeding along the continental shelf, and they were successful too.”
These findings highlight the adaptability of elephant seals, suggesting that they may be able to withstand environmental perturbations such as climate change because the population is not dependent on a single foraging strategy.
This research is also providing valuable oceanographic data. While ocean surface temperatures can be measured by satellites, oceanographers have limited temperature data from deep waters. Costa’s group has organized the temperature data collected by the elephant seals into a format that oceanographers can use and uploaded it to the World Ocean Database, providing millions of ocean temperature data points not otherwise available.
In addition to Robinson and Costa, the coauthors of the paper include Daniel Crocker, a longtime collaborator who earned his Ph.D. at UCSC and is now a biology professor at Sonoma State University; Juan Pablo Gallo-Reynoso at Unidad Guaymas in Sonora, Mexico; UCSC graduate students Cory Champagne, Melinda Fowler, Chandra Goetsch, Kimberly Goetz, Jason Hassrick, Luis Huckstadt, Jennifer Maresh, Sarah Peterson, and Nicole Teutschel; UCSC postdoctoral researchers Sara Maxwell, Birgitte McDonald, and Stella Villegas-Amtmann; Carey Kuhn of the National Marine Mammal Laboratory in Seattle; Samantha Simmons from the Marine Mammal Commission; and Ken Yoda of Nagoya University in Japan.
This project was supported by the Office of Naval Research, the International Association of Oil and Gas Producers, gifts from Steve Blank, the Rebecca and Steve Sooy Graduate Fellowship in Marine Mammals, and the Ida Benson Lynn Chair in Ocean Health.
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The above story is reprinted from materials provided by University of California – Santa Cruz. The original article was written by Tim Stephens.
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Journal Reference:
- Patrick W. Robinson, Daniel P. Costa, Daniel E. Crocker, Juan Pablo Gallo-Reynoso, Cory D. Champagne, Melinda A. Fowler, Chandra Goetsch, Kimberly T. Goetz, Jason L. Hassrick, Luis A. Hückstädt, Carey E. Kuhn, Jennifer L. Maresh, Sara M. Maxwell, Birgitte I. McDonald, Sarah H. Peterson, Samantha E. Simmons, Nicole M. Teutschel, Stella Villegas-Amtmann, Ken Yoda. Foraging Behavior and Success of a Mesopelagic Predator in the Northeast Pacific Ocean: Insights from a Data-Rich Species, the Northern Elephant Seal. PLoS ONE, 2012; 7 (5): e36728 DOI: 10.1371/journal.pone.0036728
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Article source: http://www.sciencedaily.com/releases/2012/05/120515203058.htm
Sulfur finding may hold key to Gaia theory of Earth as living organism
ScienceDaily (May 15, 2012) Is Earth really a sort of giant living organism as the Gaia hypothesis predicts? A new discovery made at the University of Maryland may provide a key to answering this question. This key of sulfur could allow scientists to unlock heretofore hidden interactions between ocean organisms, atmosphere, and land — interactions that might provide evidence supporting this famous theory.
The Gaia hypothesis — first articulated by James Lovelock and Lynn Margulis in the 1970s — holds that Earth’s physical and biological processes are inextricably connected to form a self-regulating, essentially sentient, system.
One of the early predictions of this hypothesis was that there should be a sulfur compound made by organisms in the oceans that was stable enough against oxidation in water to allow its transfer to the air. Either the sulfur compound itself, or its atmospheric oxidation product, would have to return sulfur from the sea to the land surfaces. The most likely candidate for this role was deemed to be dimethylsulfide.
Newly published work done at the University of Maryland by first author Harry Oduro, together with UMD geochemist James Farquhar and marine biologist Kathryn Van Alstyne of Western Washington University, provides a tool for tracing and measuring the movement of sulfur through ocean organisms, the atmosphere and the land in ways that may help prove or disprove the controversial Gaia theory. Their study appears in this week’s Online Early Edition of the Proceedings of the National Academy of Sciences (PNAS).
According to Oduro and his colleagues, this work presents the first direct measurements of the isotopic composition of dimethylsulfide and of its precursor dimethylsulfoniopropionate. These measurements reveal differences in the isotope ratios of these two sulfur compounds that are produced by macroalga and phytoplankton. These measurements (1) are linked to the compounds’ metabolism by these ocean organisms and (2) carry implications for tracking dimethylsulfide emissions from the ocean to the atmosphere.
Sulfur, the tenth most abundant element in the universe, is part of many inorganic and organic compounds. Sulfur cycles sulfur through the land, atmosphere and living things and plays critical roles in both climate and in the health of organisms and ecosystems.
“Dimethylsulfide emissions play a role in climate regulation through transformation to aerosols that are thought to influence the Earth’s radiation balance,” says Oduro, who conducted the research while completing a Ph.D. in geology earth system sciences at Maryland and now is a postdoctoral fellow at the Massachusetts Institute of Technology. “We show that differences in isotopic composition of dimethylsulfide may vary in ways that will help us to refine estimates of its emission into the atmosphere and of its cycling in the oceans.”
As with many other chemical elements, sulfur consists of different isotopes. All isotopes of an element are characterized by having the same number of electrons and protons but different numbers of neutrons. Therefore, isotopes of an element are characterized by identical chemical properties, but different mass and nuclear properties. As a result, it can be possible for scientists to use unique combinations of an element’s radioactive isotopes as isotopic signatures through which compounds with that element can be traced.
“What Harry did in this research was to devise a way to isolate and measure the sulfur isotopic composition of these two sulfur compounds,” says Farquhar, a professor in the University of Maryland’s department of geology. “This was a very difficult measurement to do right, and his measurements revealed an unexpected variability in an isotopic signal that appears to be related to the way the sulfur is metabolized.
“Harry’s work establishes that we should expect to see variability in the sulfur isotope signatures of these compounds in the oceans under different environmental conditions and for different organisms. I think this will ultimately be very important for using isotopes to trace the cycling of these compounds in the surface oceans as well as the flux of dimethylsulfide to the atmosphere. The ability to do this could help us answer important climate questions, and ultimately better predict climate changes. And it may even help us to better trace connections between dimethylsulfide emissions and sulfate aerosols, ultimately testing a coupling in the Gaia hypothesis,” Farquhar says.
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- H. Oduro, K. L. Van Alstyne, J. Farquhar. Sulfur isotope variability of oceanic DMSP generation and its contributions to marine biogenic sulfur emissions. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1117691109
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Article source: http://www.sciencedaily.com/releases/2012/05/120515203100.htm
Statistical analysis projects future temperatures in North America
ScienceDaily (May 15, 2012) For the first time, researchers have been able to combine different climate models using spatial statistics — to project future seasonal temperature changes in regions across North America.
They performed advanced statistical analysis on two different North American regional climate models and were able to estimate projections of temperature changes for the years 2041 to 2070, as well as the certainty of those projections.
The analysis, developed by statisticians at Ohio State University, examines groups of regional climate models, finds the commonalities between them, and determines how much weight each individual climate projection should get in a consensus climate estimate.
Through maps on the statisticians’ website (http://www.stat.osu.edu/~sses/collab_warming.html), people can see how their own region’s temperature will likely change by 2070 — overall, and for individual seasons of the year.
Given the complexity and variety of climate models produced by different research groups around the world, there is a need for a tool that can analyze groups of them together, explained Noel Cressie, professor of statistics and director of Ohio State’s Program in Spatial Statistics and Environmental Statistics.
Cressie and former graduate student Emily Kang, now at the University of Cincinnati, present the statistical analysis in a paper published in the International Journal of Applied Earth Observation and Geoinformation.
“One of the criticisms from climate-change skeptics is that different climate models give different results, so they argue that they don’t know what to believe,” he said. “We wanted to develop a way to determine the likelihood of different outcomes, and combine them into a consensus climate projection. We show that there are shared conclusions upon which scientists can agree with some certainty, and we are able to statistically quantify that certainty.”
For their initial analysis, Cressie and Kang chose to combine two regional climate models developed for the North American Regional Climate Change Assessment Program. Though the models produced a wide variety of climate variables, the researchers focused on temperatures during a 100-year period: first, the climate models’ temperature values from 1971 to 2000, and then the climate models’ temperature values projected for 2041 to 2070. The data were broken down into blocks of area 50 kilometers (about 30 miles) on a side, throughout North America.
Averaging the results over those individual blocks, Cressie and Kang’s statistical analysis estimated that average land temperatures across North America will rise around 2.5 degrees Celsius (4.5 degrees Fahrenheit) by 2070. That result is in agreement with the findings of the United Nations Intergovernmental Panel on Climate Change, which suggest that under the same emissions scenario as used by NARCCAP, global average temperatures will rise 2.4 degrees Celsius (4.3 degrees Fahrenheit) by 2070. Cressie and Kang’s analysis is for North America — and not only estimates average land temperature rise, but regional temperature rise for all four seasons of the year.
Cressie cautioned that this first study is based on a combination of a small number of models. Nevertheless, he continued, the statistical computations are scalable to a larger number of models. The study shows that climate models can indeed be combined to achieve consensus, and the certainty of that consensus can be quantified.
The statistical analysis could be used to combine climate models from any region in the world, though, he added, it would require an expert spatial statistician to modify the analysis for other settings.
The key is a special combination of statistical analysis methods that Cressie pioneered, which use spatial statistical models in what researchers call Bayesian hierarchical statistical analyses.
The latter techniques come from Bayesian statistics, which allows researchers to quantify the certainty associated with any particular model outcome. All data sources and models are more or less certain, Cressie explained, and it is the quantification of these certainties that are the building blocks of a Bayesian analysis.
In the case of the two North American regional climate models, his Bayesian analysis technique was able to give a range of possible temperature changes that includes the true temperature change with 95 percent probability.
After producing average maps for all of North America, the researchers took their analysis a step further and examined temperature changes for the four seasons. On their website, they show those seasonal changes for regions in the Hudson Bay, the Great Lakes, the Midwest, and the Rocky Mountains.
In the future, the region in the Hudson Bay will likely experience larger temperature swings than the others, they found.
That Canadian region in the northeast part of the continent is likely to experience the biggest change over the winter months, with temperatures estimated to rise an average of about 6 degrees Celsius (10.7 degrees Fahrenheit) — possibly because ice reflects less energy away from Earth’s surface as it melts. Hudson Bay summers, on the other hand, are estimated to experience only an increase of about 1.2 degrees Celsius (2.1 degrees Fahrenheit).
According to the researchers’ statistical analysis, the Midwest and Great Lakes regions will experience a rise in temperature of about 2.8 degrees Celsius (5 degrees Fahrenheit), regardless of season. The Rocky Mountains region shows greater projected increases in the summer (about 3.5 degrees Celsius, or 6.3 degrees Fahrenheit) than in the winter (about 2.3 degrees Celsius, or 4.1 degrees Fahrenheit).
In the future, the researchers could consider other climate variables in their analysis, such as precipitation.
This research was supported by NASA’s Earth Science Technology Office. The North American Regional Climate Change Assessment Program is funded by the National Science Foundation, the U.S. Department of Energy, the National Oceanic and Atmospheric Administration, and the U.S. Environmental Protection Agency office of Research and Development.
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The above story is reprinted from materials provided by Ohio State University, via Newswise. The original article was written by Pam Frost Gorder.
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- Emily L. Kang, Noel Cressie. Bayesian Hierarchical ANOVA of Regional Climate-Change Projections from NARCCAP Phase II. International Journal of Applied Earth Observation and Geoinformation, 2012; DOI: 10.1016/j.jag.2011.12.007
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Article source: http://www.sciencedaily.com/releases/2012/05/120515131634.htm
A supernova cocoon breakthrough
ScienceDaily (May 15, 2012) Observations with NASA’s Chandra X-ray Observatory have provided the first X-ray evidence of a supernova shock wave breaking through a cocoon of gas surrounding the star that exploded. This discovery may help astronomers understand why some supernovas are much more powerful than others.
On November 3, 2010, a supernova was discovered in the galaxy UGC 5189A, located about 160 million light years away. Using data from the All Sky Automated Survey telescope in Hawaii taken earlier, astronomers determined this supernova exploded in early October 2010 (in Earth’s time-frame).
This composite image of UGC 5189A shows X-ray data from Chandra in purple and optical data from Hubble Space Telescope in red, green and blue. SN 2010jl is the very bright X-ray source near the top of the galaxy (mouse-over for a labeled version).
A team of researchers used Chandra to observe this supernova in December 2010 and again in October 2011. The supernova was one of the most luminous that has ever been detected in X-rays.
In optical light, SN 2010jl was about ten times more luminous than a typical supernova resulting from the collapse of a massive star, adding to the class of very luminous supernovas that have been discovered recently with optical surveys. Different explanations have been proposed to explain these energetic supernovas including (1) the interaction of the supernova’s blast wave with a dense shell of matter around the pre-supernova star, (2) radioactivity resulting from a pair-instability supernova (triggered by the conversion of gamma rays into particle and anti-particle pairs), and (3) emission powered by a neutron star with an unusually powerful magnetic field.
In the first Chandra observation of SN 2010jl, the X-rays from the explosion’s blast wave were strongly absorbed by a cocoon of dense gas around the supernova. This cocoon was formed by gas blown away from the massive star before it exploded.
In the second observation taken almost a year later, there is much less absorption of X-ray emission, indicating that the blast wave from the explosion has broken out of the surrounding cocoon. The Chandra data show that the gas emitting the X-rays has a very high temperature — greater than 100 million degrees Kelvin — strong evidence that it has been heated by the supernova blast wave.
The energy distribution, or spectrum, of SN 2010jl in optical light reveals features that the researchers think are explained by the following scenario: matter around the supernova has been heated and ionized (electrons stripped from atoms) by X-rays generated when the blast wave plows through this material. While this type of interaction has been proposed before, the new observations directly show, for the first time, that this is happening.
This discovery therefore supports the idea that some of the unusually luminous supernovas are caused by the blast wave from their explosion ramming into the material around it.
In a rare example of a cosmic coincidence, analysis of the X-rays from the supernova shows that there is a second unrelated source at almost the same location as the supernova. These two sources strongly overlap one another as seen on the sky. This second source is likely to be an ultraluminous X-ray source, possibly containing an unusually heavy stellar-mass black hole, or an intermediate mass black hole.
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- Poonam Chandra, Roger A. Chevalier, Christopher M. Irwin, Nikolai Chugai, Claes Fransson, Alicia M. Soderberg. Strong Evolution of X-Ray Absorption in the Type IIn Supernova SN 2010jl. The Astrophysical Journal, 2012; 750 (1): L2 DOI: 10.1088/2041-8205/750/1/L2
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Article source: http://www.sciencedaily.com/releases/2012/05/120515131723.htm
This is your brain on sugar: Study in rats shows high-fructose diet sabotages learning, memory
ScienceDaily (May 15, 2012) Attention, college students cramming between midterms and finals: Binging on soda and sweets for as little as six weeks may make you stupid.
A new UCLA rat study is the first to show how a diet steadily high in fructose slows the brain, hampering memory and learning — and how omega-3 fatty acids can counteract the disruption. The peer-reviewed Journal of Physiology publishes the findings in its May 15 edition.
“Our findings illustrate that what you eat affects how you think,” said Fernando Gomez-Pinilla, a professor of neurosurgery at the David Geffen School of Medicine at UCLA and a professor of integrative biology and physiology in the UCLA College of Letters and Science. “Eating a high-fructose diet over the long term alters your brain’s ability to learn and remember information. But adding omega-3 fatty acids to your meals can help minimize the damage.”
While earlier research has revealed how fructose harms the body through its role in diabetes, obesity and fatty liver, this study is the first to uncover how the sweetener influences the brain.
The UCLA team zeroed in on high-fructose corn syrup, an inexpensive liquid six times sweeter than cane sugar, that is commonly added to processed foods, including soft drinks, condiments, applesauce and baby food. The average American consumes more than 40 pounds of high-fructose corn syrup per year, according to the U.S. Department of Agriculture. “We’re not talking about naturally occurring fructose in fruits, which also contain important antioxidants,” explained Gomez-Pinilla, who is also a member of UCLA’s Brain Research Institute and Brain Injury Research Center. “We’re concerned about high-fructose corn syrup that is added to manufactured food products as a sweetener and preservative.”
Gomez-Pinilla and study co-author Rahul Agrawal, a UCLA visiting postdoctoral fellow from India, studied two groups of rats that each consumed a fructose solution as drinking water for six weeks. The second group also received omega-3 fatty acids in the form of flaxseed oil and docosahexaenoic acid (DHA), which protects against damage to the synapses — the chemical connections between brain cells that enable memory and learning.
“DHA is essential for synaptic function — brain cells’ ability to transmit signals to one another,” Gomez-Pinilla said. “This is the mechanism that makes learning and memory possible. Our bodies can’t produce enough DHA, so it must be supplemented through our diet.”
The animals were fed standard rat chow and trained on a maze twice daily for five days before starting the experimental diet. The UCLA team tested how well the rats were able to navigate the maze, which contained numerous holes but only one exit. The scientists placed visual landmarks in the maze to help the rats learn and remember the way.
Six weeks later, the researchers tested the rats’ ability to recall the route and escape the maze. What they saw surprised them.
“The second group of rats navigated the maze much faster than the rats that did not receive omega-3 fatty acids,” Gomez-Pinilla said. “The DHA-deprived animals were slower, and their brains showed a decline in synaptic activity. Their brain cells had trouble signaling each other, disrupting the rats’ ability to think clearly and recall the route they’d learned six weeks earlier.”
The DHA-deprived rats also developed signs of resistance to insulin, a hormone that controls blood sugar and regulates synaptic function in the brain. A closer look at the rats’ brain tissue suggested that insulin had lost much of its power to influence the brain cells.
“Because insulin can penetrate the blood-brain barrier, the hormone may signal neurons to trigger reactions that disrupt learning and cause memory loss,” Gomez-Pinilla said.
He suspects that fructose is the culprit behind the DHA-deficient rats’ brain dysfunction. Eating too much fructose could block insulin’s ability to regulate how cells use and store sugar for the energy required for processing thoughts and emotions.
“Insulin is important in the body for controlling blood sugar, but it may play a different role in the brain, where insulin appears to disturb memory and learning,” he said. “Our study shows that a high-fructose diet harms the brain as well as the body. This is something new.”
Gomez-Pinilla, a native of Chile and an exercise enthusiast who practices what he preaches, advises people to keep fructose intake to a minimum and swap sugary desserts for fresh berries and Greek yogurt, which he keeps within arm’s reach in a small refrigerator in his office. An occasional bar of dark chocolate that hasn’t been processed with a lot of extra sweetener is fine too, he said.
Still planning to throw caution to the wind and indulge in a hot-fudge sundae? Then also eat foods rich in omega-3 fatty acids, like salmon, walnuts and flaxseeds, or take a daily DHA capsule. Gomez-Pinilla recommends one gram of DHA per day.
“Our findings suggest that consuming DHA regularly protects the brain against fructose’s harmful effects,” said Gomez-Pinilla. “It’s like saving money in the bank. You want to build a reserve for your brain to tap when it requires extra fuel to fight off future diseases.”
The UCLA study was funded by the National Institute of Neurological Disorders and Stroke. Gomez-Pinilla’s lab will next examine the role of diet in recovery from brain trauma.
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- R. Agrawal, F. Gomez-Pinilla. ‘Metabolic syndrome’ in the brain: deficiency in omega-3 fatty acid exacerbates dysfunctions in insulin receptor signalling and cognition. The Journal of Physiology, 2012; 590 (10): 2485 DOI: 10.1113/jphysiol.2012.230078
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Article source: http://www.sciencedaily.com/releases/2012/05/120515150938.htm
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