Vitamin E in vegetable oils and nuts prevents cancer, according to research done at Rutgers University and the Cancer Institute of New Jersey.

Next time you need to choose between vegetable oil and margarine in that favorite recipe, think about your health and reach for the oil.

While the question of whether vitamin E prevents or promotes cancer has been widely debated in scientific journals and in the news media, scientists at the Center for Cancer Prevention Research, at Rutgers Ernest Mario School of Pharmacy, and the Cancer Institute of New Jersey, believe that two forms of vitamin E – gamma and delta-tocopherols – found in soybean, canola and corn oils as well as nuts do prevent colon, lung, breast and prostate cancers.

“There are studies suggesting that vitamin E actually increases the risk of cancer and decreases bone density,” says Chung S. Yang, director of the center. “Our message is that the vitamin E form of gamma-tocopherols, the most abundant form of vitamin E in the American diet, and delta-tocopherols, also found in vegetable oils, are beneficial in preventing cancers while the form of vitamin E, alpha- tocopherol, the most commonly used in vitamin E supplements, has no such benefit.”

Director of the Center for Cancer Prevention Research at Rutgers Ernest Mario School of Pharmacy

Yang and colleagues, Nanjoo Suh and Ah-Ng Tony Kong, summarized their findings recently in Cancer Prevention Research, a journal of the American Association for Cancer Research. In a Commentary, “Does Vitamin E Prevent or Promote Cancer?” the Rutgers scientists discuss animal studies done at Rutgers as well as human epidemiological studies that have examined the connection between vitamin E and cancer.

Yang says Rutgers scientists conducting animal studies for colon, lung, breast and prostate cancer found that the forms of vitamin E in vegetable oils, gamma and delta-tocopherols, prevent cancer formation and growth in animal models.

“When animals are exposed to cancer-causing substances, the group that was fed these tocopherols in their diet had fewer and smaller tumors,” Yang says.  “When cancer cells were injected into mice these tocopherols also slowed down the development of tumors.”

 In researching colon cancer, Yang pointed to another recently published paper in Cancer Prevention Research indicating that the delta-tocopherol form of vitamin E was more effective than other forms of vitamin E in suppressing the development of colon cancer in rats.

This is good news for cancer research. Recently, in one of the largest prostate cancer clinical trials in the United States and Canada, scientists found that the most commonly used form of vitamin E supplements, alpha-tocopherol, not only did not prevent prostate cancer, but its use significantly increased the risk of this disease among healthy men.

 This is why, Yang says, it is important to distinguish between the different forms of vitamin E and conduct more research on its cancer preventive and other biological effects.

“For people who think that they need to take vitamin E supplements,” Yang says, “taking a mixture of vitamin E that resembles what is in our diet would be the most prudent supplement to take.”

 

 

Groundwater resilience to climate change in Africa  Shallow groundwater supply in rural Africa.

This one-year DFID-funded research project aimed to improve the understanding of the resilience of African groundwater to climate change and links to livelihoods. This is an area of science that has been under-researched, but has much relevance for the formulation of climate adaptation policies; see project background. Groundwater provides most of the domestic water in rural Africa and supports poverty reduction through irrigation.

Reliance on groundwater is likely to increase as rainfall becomes more variable and demand for water becomes greater.</p> <h5>Download the Final ReportDownload a summary of the project results in the Final Report 

The aim of the project was to improve understanding of the impacts of climate change on groundwater resources and local demand; there were three key objectives:To strengthen the evidence base linking climate change, climate variability, aquifer resilience and livelihood vulnerability.To support local and international research agendas and programmes, including the ability to collect and interpret data, and transform data into policy-relevant information and knowledge.To develop evidence-based guidance on assessing how groundwater can support adaptation and build resilience to climate change.

Project team

The BGS-led project team brought together UK researchers from BGS, ODI and UCL with African research institutions in Nigeria, Tanzania and Ethiopia. This interdisciplinary project team encompassed skills in international water resources, water policy and governance and water supply. </p> <p>A steering group, comprising senior academics, representatives from the donor community and users, provided guidance to the project team to ensure appropriate and high quality outputs were provided to the policy community.</p> <h2>Project outcomes</h2> <p>There are several outcomes and outputs from this research:A series of quantitative groundwater maps for Africa.

The first of their kind, the maps indicate the wide variation in groundwater resources across the continent. For much of Africa, carefully sited and constructed boreholes will be able to sustain rural handpumps. The potential for shallow boreholes yielding greater than 5 l/s is not widespread across Africa, although smaller yields of 0.5 to 5 l/s will be easier to find. Large groundwater stores in the major sedimentary basins, which can accommodate high-yielding boreholes, are often far from population centres and associated with deep water-levels.

DURHAM, N.H. -- University of New Hampshire researchers have found that residents of Louisiana and Florida most acutely and directly affected by the BP Deepwater Horizon disaster -- the largest marine oil spill in U.S. history -- said they have changed their views on other environmental issues as a result of the spill.

"If disasters teach any lessons, then experience with the Gulf oil spill might be expected to alter opinions about the need for environmental protection. About one-fourth of our respondents said that as a result of the spill, their views on other environmental issues such as global warming or protecting wildlife had changed," said Lawrence Hamilton, professor of sociology at the University of New Hampshire.

“This proportion rose to 35 percent among those most affected economically by the spill. People reporting changed views also expressed greater concern about sea level rise due to climate change, more support for a moratorium on deepwater drilling, and were more likely to favor alternative energy rather than increased oil exploration,” Hamilton said.

Hamilton and his colleagues Thomas Safford, assistant professor of sociology, and Jessica Ulrich, a doctoral student in sociology, present their findings in the journal Social Science Quarterly in the article “In the Wake of the Spill: Environmental Views Along the Gulf Coast.”

The research results are based on surveys of 2,023 residents of the Gulf Coast conducted in the aftermath of the explosion on the BP Deepwater Horizon oil rig in April 2010. Telephone interviews were conducted with 1,017 residents of Louisiana’s Plaquemines and Terrebonne parishes and 1,006 residents of Florida’s Bay, Gulf, and Franklin coun­ties. Most of the interviews took place between the successful capping of the well in July 2010, and the completion of a final relief well in September 2010. All told, an estimated 4.4 million barrels of oil escaped from the well, some of it washing ashore on wetlands, barrier islands, and beaches of Louisiana, Mississippi, Alabama, and the Florida Panhandle.

Louisiana residents more often reported that the spill had major effects on them and their families. They also saw more serious consequences from extreme weather, and greater threats from sea level rise caused by climate change. However, they were less likely than Florida residents to favor a moratorium on deepwater drilling, increased use of alternative energy, or conservation of natural resources.

“The deepwater moratorium was meant to reduce the risk of further oil spills in the immediate future. Alternative energy development or conservation might have longer-term benefits, reducing the risk both of oil spills and increased flooding. Thus, we see a contrast between Louisiana residents’ greater exposure to environment-related disasters and weaker support for these environmental protections,” Hamilton said.

While Louisiana has welcomed oil and today benefits to the tune of roughly $65 billion a year, Florida earns a similar amount from tourism. Floridians have actively opposed offshore oil drilling, which is currently banned in state waters.

“The pattern of responses from coastal Louisiana, where many more people reported effects from the spill, extreme weather, or threats from climate-related sea-level rise—but fewer supported a deepwater moratorium, alternative energy, or resource conservation—reflects socioeconomic development around oil and gas. Specialization has been channeled partly by physical characteristics of the Louisiana coastline itself,” Hamilton said.

“Florida’s Gulf Coast geography supported development in different directions, so today there are fewer oil-related jobs but much amenity development also at risk from spills and climate effects. From a perspective shaped by this different coastal landscape, steps that might reduce such risks while slowing oil and gas development appeared more attractive,” he said.

Read more: http://www.unh.edu/news/cj_nr/2012/apr/lw12oilspill.cfm#ixzz1rqlvy8aR

Herschel spots comet massacre around nearby star

Herschel’s image of Fomalhaut

 
11 April 2012
ESA’s Herschel Space Observatory has studied the dusty belt around the nearby star Fomalhaut. The dust appears to be coming from collisions that destroy up to thousands of icy comets every day.

  Fomalhaut is a young star, just a few hundred million years old, and twice as massive as the Sun. Its dust belt was discovered in the 1980s by the IRAS satellite, but Herschel’s new images of the belt show it in much more detail at far-infrared wavelengths than ever before.

Bram Acke, at the University of Leuven in Belgium, and colleagues analysed the Herschel observations and found the dust temperatures in the belt to be between –230 and –170ºC. However, because Fomalhaut is slightly off-centre and closer to the southern side of the belt, the southern side is warmer and brighter than the northern side.

Both the narrowness and asymmetry of the belt are thought to be due to the gravity of a possible planet in orbit around the star, as suggested by earlier Hubble Space Telescope images.

The Herschel data show that the dust in the belt has the thermal properties of small solid particles, with sizes of only a few millionths of a metre across.

But this created a paradox because the Hubble Space Telescope observations suggested solid grains more than ten times larger.

Those observations collected starlight scattering off the grains in the belt and showed it to be very faint at Hubble’s visible wavelengths, suggesting that the dust particles are relatively large. But that appears to be incompatible with the temperature of the belt as measured by Herschel in the far-infrared.

To resolve the paradox, Dr Acke and colleagues suggest that the dust grains must be large fluffy aggregates, similar to dust particles released from comets in our own Solar System.  
 
These would have both the correct thermal and scattering properties. However, this leads to another problem.

The bright starlight from Fomalhaut should blow small dust particles out of the belt very rapidly, yet such grains appear to remain abundant there.

The only way to overcome this contradiction is to resupply the belt through continuous collisions between larger objects in orbit around Fomalhaut, creating new dust.

To sustain the belt, the rate of collisions must be impressive: each day, the equivalent of either two 10 km-sized comets or 2000 1 km-sized comets must be completely crushed into small fluffy, dust particles.

“I was really surprised,” says Dr Acke, “To me this was an extremely large number.”

To keep the collision rate so high, there must be between 260 billion and 83 trillion comets in the belt, depending on their size. Our own Solar System has a similar number of comets in its Oort Cloud, which formed from objects scattered from a disc surrounding the Sun when it was as young as Fomalhaut.

“These beautiful Herschel images have provided the crucial information needed to model the nature of the dust belt around Fomalhaut,” says Göran Pilbratt, ESA Herschel Project Scientist.

Contact for further information
 
 

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Leo McCluskey, MD, MBE, associate professor of Neurology, explains our improved understanding of Amyotrophic lateral sclerosis (ALS) and how it shares similar disease causes with another neurodegenerative disease - Frontotemporal Lobar Degeneration (FTLD). From the 2012 Penn FTLD Caregiver Conference.

MESSENGER Provides New Look at Mercury's Landscape, Metallic Core, and Polar Shadows

Spacecraft concludes primary mission, looks toward second year at innermost planet

MESSENGER completed its one-year primary mission on March 17. Since moving into orbit about Mercury a little over one year ago, the spacecraft has captured nearly 100,000 images and returned data that have revealed new information about the planet, including its topography, the structure of its core, and areas of permanent shadow at the poles that host the mysterious polar deposits. The latest findings are presented in two papers published online in Science Express today, and in 57 papers presented this week at the 43rd Lunar and Planetary Science Conference (LPSC) in The Woodlands, Texas. Team members at the meeting will also preview MESSENGER's extended mission, set to run to March 2013. "The first year of MESSENGER orbital observations has revealed many surprises," says MESSENGER Principal Investigator Sean C. Solomon, of the Carnegie Institution of Washington. "From Mercury's extraordinarily dynamic magnetosphere and exosphere to the unexpectedly volatile-rich composition of its surface and interior, our inner planetary neighbor is now seen to be very different from what we imagined just a few years ago. The number and diversity of new findings being presented this week to the scientific community in papers and presentations provide a striking measure of how much we have learned to date." Mercury's Landscape Ranging observations from MESSENGER's Mercury Laser Altimeter (MLA) have provided the first-ever precise topographic model of the planet's northern hemisphere and characterized slopes and surface roughness over a range of spatial scales. From MESSENGER's eccentric, near-polar orbit, the MLA illuminates surface areas as wide as 15 to 100 meters, spaced about 400 meters apart. The spread in elevations is considerably smaller than those of Mars or the Moon, notes MESSENGER Co-investigator Maria T. Zuber, author of one of the papers published in Science Express. According to Zuber, of the Massachusetts Institute of Technology, the most prominent feature is an extensive area of lowlands at high northern latitudes that hosts the volcanic northern plains. Within this lowland region is a broad topographic rise that formed after the volcanic plains were emplaced. At mid-latitudes, the interior of the Caloris impact basin — 1,500 kilometers wide — has been modified so that part of the basin floor now stands higher than the rim, Zuber says. "The elevated portion of the floor of Caloris appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes," she writes. "Collectively, these features imply that long-wavelength changes to Mercury's topography occurred after the earliest phases of the planet's geological history." A Surprising Core Scientists have also come up with the first precise model of Mercury's gravity field that, when combined with the topographic data and earlier information on the planet's spin state, sheds light on the planet's internal structure, the thickness of its crust, the size and state of its core, and its tectonic and thermal history. Mercury's core is huge for the planet's size, about 85% of the planetary radius, even larger than previous estimates. The planet is sufficiently small that at one time many scientists thought the interior should have cooled to the point that the core would be solid. However, subtle dynamical motions measured from Earth-based radar combined with parameters of the gravity field, as well as observations of the magnetic field that signify an active core dynamo, indicate that Mercury's core is at least partially liquid. "MESSENGER's observations of the gravity field have let us peer inside Mercury and get the first good look at its largest component — the core," says Case Western Reserve University's Steven A. Hauck II, coauthor of one of the papers published in Science Express. Scientists sought to unravel the mystery of the size and state of Mercury's core by studying its effect on long-wavelength variations in the planet's gravity field, and recent results point to an interior structure for Mercury that is much different from what was expected. "Mercury's core may not look like any other terrestrial planetary core," Hauck says. "The structure certainly is different from that of Earth, which has a metallic, liquid outer core sitting above a solid inner core. Mercury appears to have a solid silicate crust and mantle overlying a solid, iron sulfide outer core layer, a deeper liquid core layer, and possibly a solid inner core." These findings will have implications for how Mercury's magnetic field is generated and for understanding how the planet evolved thermally, Hauck adds. Polar Shadows A chief goal of MESSENGER's primary mission was to understand the nature of the radar-bright deposits at the poles of Mercury. The leading proposal since the deposits were discovered has been that radar-bright material consists dominantly of frozen water ice. "We've never had the imagery available before to see the surface where these radar-bright features are located," says Nancy L. Chabot, instrument scientist for MESSENGER's Mercury Dual Imaging System (MDIS) at The Johns Hopkins University Applied Physics Laboratory (APL). "MDIS images show that all the radar-bright features near Mercury's south pole are located in areas of permanent shadow, and near Mercury's north pole such deposits are also seen only in shadowed regions, results consistent with the water-ice hypothesis." This finding is not definitive proof that those deposits are water ice, says Chabot, who is presenting her results at LPSC. And some of the radar-bright deposits are located in craters that provide thermally challenging environments to the water-ice theory. For instance, for the radar-bright material in many of the craters to be water ice would require that there be a thin layer of insulation to keep it colder than the surface, Chabot says. But the MDIS images, combined with ongoing analysis of data from MESSENGER's Neutron Spectrometer and the MLA, will provide a more complete picture of the nature of the deposits.

 

Lori Stevens, a biologist at the University of Vermont, and her colleagues, found that 38 percent of the kissing bugs they collected in Arizona and California contained human blood.

This upends the previous understanding of insect experts and doctors that the eleven species of kissing bugs that occur in the US don’t regularly feed on people.

“This finding was totally unexpected,” says Dr. Stephen Klotz, head of the infectious diseases department at the University of Arizona medical school and a co-author on the study.

And more than 50 percent of the bugs the research team collected also carried Trypanosoma cruzi, the parasite that causes Chagas disease.

Their study is reported in the March 14 online edition of the journal Emerging Infectious Diseases.

“The basic message is that the bug is out there, and it’s feeding on humans, and carries the parasite,” says Stevens, “so there may be greater potential for humans to have the disease in the United States than previously thought.”

A quiet killer
So far, little of that potential has been realized. Only seven cases of Chagas disease transmitted by kissing bugs have been documented in the United States.

“We think the actual transmission is higher than the seven cases we have identified,” says Patricia Dorn, an expert on Chagas disease at Loyola University and co-author on the new study, “but, even with these findings, we think the transmission of Chagas — of the T. cruzi parasite — is still very low in the US."

 

EPA Funding Available for Study of Raritan River in NJ

Release Date: 03/13/2012
Contact Information: Mary Mears (212) 637-3673; mears.mary@epa.gov

(New York, N.Y.) The U.S. Environmental Protection Agency is encouraging applications for $100,000 in funding to study contaminated sites and other sources of pollution that are impacting water quality in the lower and middle Raritan River. This funding is part of an EPA Raritan River Initiative, which will support the analysis of existing data to enable environmental agencies, institutions, community groups and local governments to identify data gaps, plan future research and make other environmental decisions.

The Raritan River runs from west of Somerville, N.J. into the Raritan Bay. The river and the surrounding watershed is home to over one million people, providing drinking water, transportation and recreation opportunities and important habitat for wildlife. The watershed is impacted by many sources of pollution, including contaminated sites, industrial facilities and sewage treatment systems. While there is sampling data collected within the Raritan River watershed, this information is fragmented.

“This funding demonstrates the EPA's continued commitment to a cleaner and healthier Raritan River and the health of everyone who enjoys it," said EPA Regional Administrator Judith A. Enck. "The data and information collected will help Raritan River communities better understand pollution that has affected river conditions and will assist in decision-making on the best ways to improve water quality.”

Using the funding, the selected applicant will identify high priority sites and sources of pollution that are potentially impacting the river. The resulting site list and associated data will then be made available to the public and put into a format that can be used by state agencies, country and local governments, non-profit organizations and other stakeholders to make environmental decisions. The data would also be used to create an interactive website to show exact locations of potentially polluting sites along the river along with the data for each site.

All applications are due no later than April 23, 2012 at 5:00 p.m. EDT. Additional information on the grants, including guidance on eligibility and procedures for applying, is available at http://www.epa.gov/region2/grants/ or through http://www.grants.gov.

Follow EPA Region 2 on Twitter at http://www.twitter.com/eparegion2 and Facebook at http://www.facebook.com/eparegion2.

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9 March 2012
This image from the Ikonos-2 satellite shows the sandy and rocky terrain of the Sahara desert in western Algeria.

The largest country in Africa, Algeria is covered more than 90% by the Sahara desert. Major oil and natural gas deposits lie beneath the Sahara, contributing to Algeria’s position as one of the wealthiest African nations.
In its entirety, the Sahara stretches from the Atlantic Ocean to the Red Sea and is centred around the Tropic of Cancer. It is the world’s largest hot desert, covering an area of about 9 million sq km over parts of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Tunisia and Sudan.

With the Mediterranean Sea almost 500 km away, the closest town to the area pictured here is Taghit in the Algerian province of Béchar.

Taghit’s economy is based on agriculture and tourism. Travellers are drawn to the area’s large sand dunes, which are the main feature of the Sahara’s Grand Erg Occidental. The region receives less than 25 cm of rainfall per year.

Inaugurated in 2007, the Taghit National Park was established to help stop the advance of the Sahara desert and protect diverse wildlife. The project seeks to guard grasslands, restore palm groves, renew the planting of acacias and reforest the degrading land.

This image was acquired on 23 April 2008 at a spatial resolution of 4 m by the commercial Ikonos-2 satellite.

ESA supports Ikonos-2 as a Third Party Mission, which means that the Agency uses its multi-mission European ground infrastructure and expertise to acquire, process and distribute data from the satellite to its wide scientific user community.

Salk scientists discover a single injection of cocaine or methamphetamine produces a long-lasting cellular memory trace that could be the brain's way of resisting powerful psychostimulants

March 07, 2012

LA JOLLA, CA—A single injection of cocaine or methamphetamine in mice caused their brains to put the brakes on neurons that generate sensations of pleasure, and these cellular changes lasted for at least a week, according to research by scientists at the Salk Institute for Biological Studies.

Their findings, reported March 7, 2012 in Neuron, suggest this powerful reaction to the drug assault may be a protective, anti-addiction response. The scientists theorize that it might be possible to mimic this response to treat addiction to these drugs and perhaps others, although more experiments are required to explore this possibility.

Michaelanne Munoz, UCSD graduate student and Paul Slesinger, Associate Professor, Clayton Foundation Laboratories for Peptide Biology.

Image: Courtesy of the Salk Institute for Biological Studies

"It was stunning to discover that one exposure to these drugs could promote such a strong response that lasts well after the drug has left the body," says Paul Slesinger, an associate professor in the Clayton Foundation Laboratories for Peptide Biology. "We believe this could be the brain's immediate response to counteract the stimulation of these drugs."

Scientists are trying to better understand the brain's response to psychoactive drugs in hopes of finding new ways to prevent and treat addiction. This research has become especially important as the number of deaths due to drug abuse now exceeds those due to car accidents, with more than 37,000 people dying from drugs in 2009, according to the Centers for Disease Control and Prevention. Slesinger and Christian Lüscher, a long-time collaborator at the University of Geneva, have been investigating the cellular changes in the brain that occur with drug abuse.

Dopamine is a primary neurotransmitter used in the brain's reward pathway—generally speaking, the activity of dopamine neurons in the reward pathway increases in response to rewards, such as sex, food and drugs. Psychostimulants, such as methamphetamine and cocaine, co-opt this pathway and alter the brain's response to dopamine. Understanding the neuroadaptations that occur in the reward pathway in response to drugs of abuse may lead to the development of a treatment for drug addiction.

Previous research has shown that use of cocaine and methamphetamine in mice enhances excitatory connections to dopamine neurons. While most research has focused on these excitatory neurons, Slesinger and his colleagues looked at neurons that inhibit dopamine transmission, and found that one injection of cocaine or methamphetamine produces a profound change in the function of these inhibitory GABA neurons. These neurons were not able to control how they fired, so they would release more than the usual amount of inhibitory neurotransmitter.

"This persistent change in the inhibitory neurons occurs simultaneously with enhancement of excitatory inputs, indicating a possible compensatory mechanism that could be protective during exposure to drugs," Slesinger says.

The Salk researchers identified a change in the biochemical pathway in inhibitory GABA neurons that led to this protective effect. It involved a change in the activity of a protein, known as a phosphatase, which controls the levels of a receptor known to be important for controlling the electrical activity of the GABA neuron.

The left image shows GABA inhibitory neurons (labeled green) in the brain's reward pathway.

The right panel shows electrical activity of GABA inhibitory neuron in a Saline-injected or methamphetamine (METH)-injected mouse.

Activation of the GABA type B receptor normally silences electrical activity, but has no effect in a mouse 24 hours after a single injection of methamphetamine

Image: Courtesy of Kelly Tan and Claire Padgett, Salk Institute for Biological Studies

"This particular pathway—involving a GABA type B receptor and a particular type of potassium channel—was affected by psychostimulants in these inhibitory neurons," Slesinger says. "We noticed a dramatic reduction in the strength of this signaling pathway, which we showed was due to a decrease in the activity of the GABA_B receptor and the potassium channel on the neuron's membrane surface."

"If we could tap into this pathway—enhance the ability of inhibitory neurons to control the activity of dopamine neurons—we might be able to treat some types of drug addiction," Slesinger says.

What is not known is how long the drug response lasts—this study only looked at the brains of mice at two time points, 24 hours and seven days, after drug use—and why addiction ultimately develops with chronic drug use. These are questions Slesinger and his colleagues are now investigating.

The study's two lead authors are Claire Padgett, a former postdoctoral researcher in the Slesinger laboratory, and Arnaud Lalive, a doctoral student at the University of Geneva, who is working in the laboratory of Christian Lüscher, also a co-author. Other participating investigators include: Michaelanne Munoz, of the University of California San Diego; Stephen Moss and colleagues from Tufts University School of Medicine; Rafael Luján, from the Universidad de Castilla-La Mancha in Albacete, Spain; and investigators from Hokkaido University School of Medicine in Sapporo, Japan; University College in London; and AstraZeneca in Cheshire, United Kingdom.

The study was funded by the National Institute on Drug Abuse, the National Institute of Neurological Disorders and Stroke, Catharina Foundation and the Spanish Ministry of Education and Science.

About the Salk Institute for Biological Studies:
The Salk Institute for Biological Studies is one of the world's preeminent basic research institutions, where internationally renowned faculty probe fundamental life science questions in a unique, collaborative, and creative environment. Focused both on discovery and on mentoring future generations of researchers, Salk scientists make groundbreaking contributions to our understanding of cancer, aging, Alzheimer's, diabetes and infectious diseases by studying neuroscience, genetics, cell and plant biology, and related disciplines.

Faculty achievements have been recognized with numerous honors, including Nobel Prizes and memberships in the National Academy of Sciences. Founded in 1960 by polio vaccine pioneer Jonas Salk, M.D., the Institute is an independent nonprofit organization and architectural landmark.

For more information:
Neuron
Authors: Claire L. Padgett, Arnaud L. Lalive, Kelly R. Tan, Miho Terunuma, Michaelanne B. Munoz, Menelas N. Pangalos, Jose Martinez-Hernandez, Masahiko Watanabe, Stephen J. Moss, Rafael Lujan, Christian Luscher, Paul A. Slesinger
Title: Methamphetamine-evoked depression of GABA_B receptor signaling in GABA neurons of the VTA

Neuron (red) accumulates messages (green) when treated with BDNF.

Studying tiny bits of genetic material that control protein formation in the brain, Johns Hopkins scientists say they have new clues to how memories are made and how drugs might someday be used to stop disruptions in the process that lead to mental illness and brain wasting diseases.

In a report published in the March 2 issue of Cell, the researchers said certain microRNAs—genetic elements that control which proteins get made in cells— are the key to controlling the actions of so-called brain-derived neurotrophic factor (BDNF), long linked to brain cell survival, normal learning and memory boosting.

During the learning process, cells in the brain’s hippocampus release BDNF, a growth-factor protein that ramps up production of other proteins involved in establishing memories. Yet, by mechanisms that were never understood, BDNF is known to increase production of less than 4 percent of the different proteins in a brain cell.

That led Mollie Meffert, M.D., Ph.D., associate professor of biological chemistry and neuroscience at the Johns Hopkins University School of Medicine to track down how BDNF specifically determines which proteins to turn on, and to uncover the role of regulatory microRNAs.

MicroRNAs are small molecules that bind to and block messages that act as protein blueprints from being translated into proteins. Many microRNAs in a cell shut down protein production, and, conversely, the loss of certain microRNAs can cause higher production of specific proteins.

The researchers measured microRNA levels in brain cells treated with BDNF and compared them to microRNA levels in neurons not treated with BDNF. The researchers noticed that levels of certain microRNAs were lower in brain cells treated with BDNF, suggesting that BDNF controls the levels of these microRNAs and, through this control, also affects protein production. Homing in on those specific microRNAS that disappeared when cells were treated with BDNF, the team found all were of the same type, so-called Let-7 microRNAs, and that all shared a common genetic sequence.

“This short genetic sequence has been shown by other researchers to behave like a bar code that can selectively prevent production of Let-7 microRNAs,” says Meffert.

To test if the loss of Let-7 microRNAs lets BDNF increase production of specific proteins, Meffert’s team genetically engineered neurons so they could no longer decrease Let-7 microRNAs. They found that treating these neurons with BDNF no longer resulted in decreased microRNA levels or an increase in learning and memory proteins.

In measuring microRNA levels in cells treated with BDNF, the researchers also found more than 174 microRNAs that increased with BDNF treatment. This suggested to the research team that BNDF treatment also can increase other microRNAs and, thereby, decrease production of certain proteins. Says Meffert, some of these proteins may need to be decreased during learning and memory, whereas others may not contribute to the process at all.

To confirm that BDNF, via microRNA action, halts the production of certain proteins, the researchers monitored living brain cells to find out where messages go in response to BDNF. Messages that aren’t translated into proteins can accumulate inside small formations within cells. Using a microscope, the researchers watched a lab dish containing brain cells that had been marked with a fluorescent molecule that labels these formations as glowing spots. Treating cells with BDNF caused the number and size of the glowing spots to increase. The researchers determined that BDNF uses microRNA to send messages to these spots where they can be exiled away from the translating machinery that turns them into protein.

“Monitoring these fluorescent complexes gave us a window that we needed to understand how BDNF is able to target the production of only certain proteins that help neurons to grow and make learning possible,” Meffert says.

Adds Meffert, “Now that we know how BDNF boosts production of learning and memory proteins, we have an opportunity to explore whether therapeutics can be designed to enhance this mechanism for treatment of patients with mental disorders and  neurodegenerative diseases like Alzheimer’s disease.”

Additional authors of the study included Yu-Wen Huang, Claudia Ruiz, Elizabeth Eyler and Kathie Lin all from Johns Hopkins University, School of Medicine.

This research was supported by funds from the Braude Foundation and the Brain Science Institute of Johns Hopkins.

Stinging and seeing

Left, a hydra stained in blue where the light-sensitive opsin gene is expressed. Right, two tentacle bulbs showing the arrangement of neurons and stinging cells (red), muscle fibers (green) and cell nuclei (blue). (David Plachetzki/UC Davis graphic)

New research from the University of California shows how the ability to detect light could have evolved before anything like an eye.

As published today (March 5) in the journal BMC Biology, the research is based on the stinging mechanism in the tiny, brainless and eyeless freshwater polyp Hydra magnipapillata. Part of a group of animals called cnidarians that includes sea anemones, corals and jellyfish, a hydra is essentially a mouth surrounded by tentacles armed with stinging cells, or cnidocytes.

The researchers — David Plachetzki, now a postdoctoral researcher at UC Davis, working with undergraduate Caitlin Fong and Professor Todd Oakley in the Department of Ecology, Evolution and Marine Biology at UC Santa Barbara — discovered a simple nervous system linking the stinging cells and nerve cells that detect light using a process similar to the human eye’s.

The nerve cells express a set of genes including opsin, a light-sensitive pigment; cyclic nucleotide gated ion channels; and arrestin. These components are basically the same as those in the light-detecting pathway in animals with eyes, including people.

The hydra fire their stingers less in bright than in dim light, the researchers found. When they blocked one of the pathway’s components, the hydra acted as if they were in dim light and fired their stingers more.

Most of the hydra’s cnidarian relatives lack eyes. But all cnidarians have cnidocyte stinging cells.

"This capacity for stinging cell regulation by light-sensitive neurons could have predated the evolution of eyes in cnidarians," Plachetzki said. Future work will be aimed at how these findings relate to the evolution of eyes in other groups of animals.

The National Science Foundation funded the work.

Scientists from Binghamton University and Cardiff University, and New York State Museum researchers, and have reported the discovery of the floor of the world's oldest forest.

"It was like discovering the botanical equivalent of dinosaur footprints," said Dr. William Stein, associate professor of biological sciences at Binghamton University, and one of the article's authors. "But the most exciting part was finding out just how many different types of footprints there were. The newly uncovered area was preserved in such a way that we were literally able to walk among the trees, noting what kind they were, where they had stood and how big they had grown."

Scientists are now piecing together a view of this ancient site, dating back about 385 million years ago, which could shed new light on the role of modern-day forests and their impact on climate change.