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Chocolate makes snails smarter - 0 views

phys.org/...-chocolate-snails-smarter.html

scibyte65 chocolate

shared by Mars Base on 27 Sep 12 - No Cached
  • some websites even maintain that dark chocolate can have beneficial effects
  • the science underpinning these claims, and you'll discover just how sparse it is
  • University of Calgary undergraduate
  • ...25 more annotations...
  • became curious about how dietary factors might affect memory
  • Despite his misgivings
  • decided to concentrate on a group of compounds – the flavonoids – found in a wide range of 'superfoods' including chocolate and green tea, focusing on one particular flavonoid, epicatechin (epi).
  • figuring out how a single component of chocolate might improve human memory is almost impossible
  • too many external factors influence memory formation
  • the pond snail Lymnaea stagnalis, to find out whether the dark chocolate flavonoid could improve their memories
  • publish their discovery that epi improves the length and strength of snail memories in The Journal of Experimental Biology
  • molluscs can be trained to remember a simple activity: to keep their breathing tubes (pneumostomes) closed when immersed in deoxygenated water
  • t pond snails usually breathe through their skins, but when oxygen levels fall, they extend the breathing tube above the surface to supplement the oxygen supply
  • e snails can be trained to remember to keep the breathing tube closed in deoxygenated water by gently tapping it when they try to open it,
  • the strength of the memory depends on the training regime.
  • identified an epi concentration – 15 mg m3 pond water – that didn't affect the snails' behaviour
  • to be sure that we're not looking at wired animals
  • ested the molluscs' memories. Explaining that a half-hour training session in deoxygenated water allows the snails to form intermediate-term memories (lasting less than 3 h) but not long-term memories (lasting 24 h or more)
  • when Fruson plunged the molluscs into deoxygenated water to tested their memories a day later, they remembered to keep their breathing tubes closed
  • provided the snails with two training sessions, the animals were able to remember to keep their breathing tubes shut more than 3 days later
  • boosted the molluscs' memories and extended the duration, but how strong were the epi-memories
  • memories can be overwritten by another memory
  • process called extinction
  • the original memory is not forgotten and if the additional memory is stored weakly
  • can be lost and the original memory restored
  • then tried to replace it with a memory where the snails could open their breathing tubes
  • instead of learning the new memory, the epi-trained snails stubbornly kept their breathing tubes shut. The epi-memory was too strong to be extinguished.
  • also found that instead of requiring a sensory organ to consolidate the snails' memories – like their memories of predators triggered by smell – epi directly affects the neurons that store the memory
  • that the cognitive effects of half a bar of dark chocolate could even help your grades: good news for chocoholics the world over.
Mars Base

Memories 'geotagged' with spatial information - 0 views

www.sciencedaily.com/...131128141405.htm

scibyte111 memories

shared by Mars Base on 01 Dec 13 - No Cached
  • Using a video game in which people navigate through a virtual town delivering objects to specific locations, a team of neuroscientists
  • has discovered how brain cells that encode spatial information form "geotags" for specific memories and are activated immediately before those memories are recalled.
  • work shows how spatial information is incorporated into memories and why remembering an experience can quickly bring to mind other events that happened in the same place
  • ...24 more annotations...
  • findings provide the first direct neural evidence for the idea that the human memory system tags memories with information about where and when they were formed
  • this study involved playing a simple video game on a bedside computer
  • The game in this experiment involved making deliveries to stores in a virtual city
  • The participants were first given a period where they were allowed to freely explore the city and learn the stores' locations
  • When the game began, participants were only instructed where their next stop was, without being told what they were delivering
  • After they reached their destination, the game would reveal the item that had been delivered, and then give the participant their next stop
  • After 13 deliveries, the screen went blank and participants were asked to remember and name as many of the items they had delivered in the order they came to mind
  • This allowed the researchers to correlate the neural activation associated with the formation of spatial memories (the locations of the stores) and the recall of episodic memories: (the list of items that had been delivered).
  • "Having these patients play our games allows us to record every action they take in the game and to measure the responses of neurons both during spatial navigation and then later during verbal recall."
  • By asking participants to recall the items they delivered instead of the stores they visited, the researchers could test whether their spatial memory systems were being activated
  • map-like nature of the neurons associated with spatial memory made this comparison possible
  • During navigation, neurons in the hippocampus and neighboring regions can often represent the patient's virtual location within the town
  • Using the brain recordings generated while the participants navigated the city, the researchers were able to develop a neural map that corresponded to the city's layout
  • As participants passed by a particular store, the researchers correlated their spatial memory of that location with the pattern of place cell activation recorded
  • With maps of place cell activations in hand, the researchers were able to cross- reference each participant's spatial memories as they accessed their episodic memories of the delivered items
  • given just the place cell activations of a participant
  • could predict, with better than chance accuracy, the item he or she was recalling
  • cannot distinguish whether these spatial memories are actually helping the participants access their episodic memories
  • seeing that this place cell activation plays a role in the memory retrieval processes
  • Earlier neuroscience research
  • had suggested the hippocampus has two distinct roles
  • tracking location information for spatial memory, and
  • recording events for episodic memory
  • This experiment provides further evidence that these roles are intertwined
Mars Base

Scientists reverse memory loss in animal brain cells - 0 views

medicalxpress.com/...everse-memory-loss-animal.html

scibyte91 BrainTraining

shared by Mars Base on 18 Apr 13 - No Cached
  • Using sea snail nerve cells, the scientists reversed memory loss by determining when the cells were primed for learning
  • scientists were able to help the cells compensate for memory loss by retraining them through the use of optimized training schedules
  • study builds on
  • ...19 more annotations...
  • 2012 investigation that pioneered this memory enhancement strategy
  • The 2012 study showed a significant increase in long-term memory in healthy sea snails
  • study's co-lead author and a research scientist
  • has developed a sophisticated mathematical model that can predict when the biochemical processes in the snail's brain are primed for learning
  • model is based on five training sessions scheduled at different time intervals ranging from 5 to 50 minutes
  • can generate 10,000 different schedules and identify the schedule most attuned to optimum learning
  • Memory is due to a change in the strength of the connections among neurons. In many diseases associated with memory deficits, the change is blocked
  • senior research scientist
  • simulated a brain disorder in a cell culture by taking sensory cells from the sea snails and blocking the activity of a gene that produces a memory protein
  • This resulted in a significant impairment in the strength of the neurons' connections, which is responsible for long-term memory
  • To mimic training sessions, cells were administered a chemical at intervals prescribed by the mathematical model
  • After five training sessions, which like the earlier study were at irregular intervals, the strength of the connections returned to near normal in the impaired cells
  • This methodology may apply to humans if we can identify the same biochemical processes in humans
  • results suggest a new strategy for treatments of cognitive impairment
  • Mathematical models might help design therapies that optimize the combination of training protocols with traditional drug treatments
  • Combining these two could enhance
  • effectiveness
  • while compensating at least in part for any limitations or undesirable side effects of drugs
  • two approaches are likely to be more effective together than separately and may have broad generalities in treating individuals with learning and memory deficits."
Mars Base

First evidence that fear memories can be reduced during sleep - 0 views

medicalxpress.com/...2013-09-evidence-memories.html

scibyte104 brain

shared by Mars Base on 23 Sep 13 - No Cached
  • A fear memory was reduced in people by exposing them to the memory over and over again while they slept
  • It's the first time that emotional memory has been manipulated in humans during sleep
  • potentially offers a new way to enhance the typical daytime treatment of phobias through exposure therapy by adding a nighttime component
  • ...21 more annotations...
  • showed a small but significant decrease in fear
  • If it can be extended to pre-existing fear, the bigger picture is that, perhaps, the treatment of phobias can be enhanced during sleep."
  • Previous projects have shown that spatial learning and motor sequence learning can be enhanced during sleep
  • wasn't previously known that emotions could be manipulated during sleep
  • 15 healthy human subjects received mild electric shocks while seeing two different faces
  • also smelled a specific odorant while viewing each face and being shocked
  • the face and the odorant both were associated with fear
  • Subjects received different odorants to smell with each face such as woody, clove, new sneaker, lemon or mint
  • when a subject was asleep, one of the two odorants was re-presented, but in the absence of the associated faces and shocks.
  • occurred during slow wave sleep when memory consolidation is thought to occur
  • Sleep is very important for strengthening new memories
  • particular odorant was being presented during sleep, it was reactivating the memory of that face over and over again
  • similar to the process of fear extinction during exposure therapy
  • When the subjects woke up, they were exposed to both faces
  • When they saw the face linked to the smell they had been exposed to during sleep, their fear reactions were lower than their fear reactions to the other face
  • Fear was measured in two ways
  • through small amounts of sweat in the skin, similar to a lie detector test
  • through neuroimaging with fMRI (functional magnetic resonance imaging).
  • fMRI results showed changes in regions associated with memory
  • and changes in patterns of brain activity in regions associated with emotion
  • These brain changes reflected a decrease in reactivity that was specific to the targeted face image associated with the odorant presented during sleep
Mars Base

Exceptional Memory Linked To Bulked-up Parts Of Brain - Science News - 0 views

www.sciencenews.org/...ed_to_bulked-up_parts_of_brain

scibyte21

shared by Mars Base on 14 Nov 11 - No Cached
  • some real-life people can remember every day of their lives in detail
  • Those superrememberers have more bulk in certain parts of their brains, possibly explaining the remarkable ability to recall minutiae from decades ago
  • brain region involved in such incredible recall has been implicated in obsessive-compulsive disorder
  • ...11 more annotations...
  • OCD and superior memory might have a common architecture in the brain
  • Scientists have long studied people with memory deficits, but there haven’t been many studies on people with exceptional memories
  • 11 people who scored off the charts for autobiographical memory. These people could effortlessly remember, for instance, what they were doing on November 2, 1989, and could also tell you that it was a Thursday
  • Using brain scans, researchers found that people with supermemories had larger brain regions associated with memory
  • a brain structure called the lentiform nucleus, a cone-shaped mass in the core of the brain, was bigger in people with exceptional memories
  • This brain area has been linked to obsessive-compulsive disorder
  • The subjects haven’t been clinically evaluated for OCD, but LePort says that there are some similarities
  • The ability to organize their memories by dates seems to relieve anxiety
  • These people could encode information more effectively, or have a better system of retrieving it, or both
  • Though no genetic tests have been performed, some of the volunteers have reported that family members share extraordinary powers of recall
  • The volunteers are now keeping detailed diaries, so that the scientists can test whether particular kinds of memories are better suited to recollection. People might be better at remembering emotional memories, for instance
Mars Base

Neuro researchers sharpen our understanding of memories - 0 views

medicalxpress.com/...05-neuro-sharpen-memories.html

scibyte45 brain memories

shared by Mars Base on 01 May 12 - No Cached
  • Scientists now have a better understanding of how precise memories are formed
  • these findings could help us to better understand memory impairments in neurodegenerative disorders like Alzheimer's disease
  • study looks at the cells in our brains, or neurons, and how they work together as a group to form memories
  • ...11 more annotations...
  • neurons are classified into two groups according to the type of chemical they produce: excitatory, who produce chemicals that increase communication between neurons, and inhibitory, who have the opposite effect, decreasing communication
  • Scientists knew that inhibitory cells enable us to refine our memories, to make them specific to a precise set of information
  • findings explain for the first time how this happens at the molecular and cell levels
  • very little research has been done on inhibitory neurons, partly because they are very difficult to study
  • In the laboratory, we simulated the formation of a new memory by using chemicals
  • measured the electrical activity within the network of cells
  • cells where we had removed CREB, we saw that the strength of the electrical connections was much weaker
  • scientists found that a factor called "CREB" plays a key role in adjusting gene expression and the strength of synapses in inhibitory neurons
  • when we increased the presence of CREB, the connections were stronger
  • This new understanding of the chemical functioning of the brain may one day lead to new treatments
  • we are unfortunately many years away from developing new treatments from this information."
Mars Base

Mars Science Laboratory: Computer Swap on Curiosity Rover - 0 views

mars.jpl.nasa.gov/...index.cfm

scibyte84 Curiosity

shared by Mars Base on 01 Mar 13 - No Cached
  • 02.28.2013
  • The ground team for NASA's Mars rover Curiosity has switched the rover to a redundant onboard computer in response to a memory issue on the computer that had been active
  • intentional swap at about 2:30 a.m. PST today (Thursday, Feb. 28) put the rover
  • ...16 more annotations...
  • "safe mode."
  • , into
  • safe mode to operational status over the next few days and is troubleshooting the condition that affected operations
  • The condition is related to a glitch in flash memory linked to the other, now-inactive, computer.
  • switched computers to get to a standard state from which to begin restoring routine operations
  • Like many spacecraft
  • Curiosity carries a pair of redundant main computers in order to have a backup available if one fails
  • Each of the computers, A-side and B-side, also has other redundant subsystems linked to just that computer
  • Curiosity is now operating on its B-side, as it did during part of the flight from Earth to Mars. It operated on its A-side from before the August 2012 landing through Wednesday.
  • While
  • resuming operations on the B-side, we are also working to determine the best way to restore the A-side as a viable backup
  • The spacecraft remained in communications at all scheduled communication windows on Wednesday, but it did not send recorded data, only current status information.
  • status information revealed that the computer had not switched to the usual daily "sleep" mode when planned
  • Diagnostic work in a testing simulation at JPL indicates the situation involved corrupted memory at an A-side memory location used for addressing memory files
  • Scientific investigations by the rover were suspended Wednesday
  • Resumption of science investigations is anticipated within several days
Mars Base

Researchers debunk the IQ myth - 0 views

medicalxpress.com/...2012-12-debunk-iq-myth.html

scibyte76 IQ

shared by Mars Base on 23 Dec 12 - No Cached
  • After conducting the largest online intelligence study on record
  • research team has concluded that the notion of measuring one's intelligence quotient or IQ by a singular, standardized test is highly misleading
  • study, which included more than 100,000 participants
  • ...8 more annotations...
  • Utilizing an online study open to anyone, anywhere in the world, the researchers asked respondents to complete 12 cognitive tests tapping memory, reasoning, attention and planning abilities, as well as a survey about their background and lifestyle habits.
  • expected a few hundred responses, but thousands and thousands of people took part, including people of all ages, cultures and creeds from every corner of the world
  • The results showed that when a wide range of cognitive abilities are explored, the observed variations in performance can only be explained with at least three distinct components: short-term memory, reasoning and a verbal component
  • No one component, or IQ, explained everything
  • scientists used a brain scanning technique known as functional magnetic resonance imaging (fMRI), to show that these differences in cognitive ability map onto distinct circuits in the brain.
  • Intriguingly, people who regularly played computer games did perform significantly better in terms of both reasoning and short-term memory
  • smokers performed poorly on the short-term memory and the verbal factors
  • people who frequently suffer from anxiety performed badly on the short-term memory factor in particular
Mars Base

Mars Science Laboratory - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/...Mars_Science_Laboratory

scibyte22 Curiosity

shared by Mars Base on 17 Nov 11 - Cached
  • Launch vehicle Atlas V 541
  • Mission duration 668 Martian sols (686 Earth days)
  • Landing August 5, 2012 (planned
  • ...11 more annotations...
  • Mass 900 kg (2,000 lb)[
  • Power Radioisotope Thermoelectric Generator (RTG)
  • the general public had an opportunity to rank nine finalist names through a public poll on the NASA website
  • Curiosity was selected, which was submitted by a sixth-grader, Clara Ma, from Kansas in an essay contest
  • 10 ft (3.0 m) in length
  • radioisotope thermoelectric generators (RTGs), as used by the successful Mars landers Viking 1 and Viking 2 in 1976
  • Radioisotope power systems are generators that produce electricity from the natural decay of plutonium-238, which is a non-fissile isotope of plutonium used in power systems for NASA spacecraft. Heat given off by the natural decay of this isotope is converted into electricity, providing constant power during all seasons and through the day and night, and waste heat can be used via pipes to warm systems, freeing electrical power for the operation of the vehicle and instruments
  • designed to produce 125 watts of electrical power from about 2000 watts of thermal power at the start of the mission
  • lifetime of 14 years, electrical power output is down to 100 watts
  • "Rover Compute Element" (RCE), contain radiation hardened memory to tolerate the extreme radiation environment from space and to safeguard against power-off cycles
  • 256 kB of EEPROM, 256 MB of DRAM, and 2 GB of flash memory
Mars Base

Prospective Alzheimer's drug builds new brain cell connections - 0 views

medicalxpress.com/...alzheimer-drug-brain-cell.html

scibyte67 Alzheimer

shared by Mars Base on 11 Oct 12 - No Cached
  • researchers have developed a new drug candidate that dramatically improves the cognitive function of rats with Alzheimer's-like mental impairment
  • intended to repair brain damage that has already occurred
  • This is about recovering function
  • ...20 more annotations...
  • t makes these things totally unique. They're not designed necessarily to stop anything. They're designed to fix what's broken. As far as we can see, they work
  • current Alzheimer's treatments, which either slow the process of cell death or inhibit cholinesterase, an enzyme believed to break down a key neurotransmitter involved in learning and memory development
  • Last month, the Pharmaceutical Research and Manufacturers of America, or PhRMA, reported that only three of 104 possible treatments have been approved in the past 13 years
  • Development of the WSU drug is only starting
  • Safety testing alone could cost more than $1 million
  • been working on their compound since 1992
  • practical utility of these early drug candidates, however, was severely limited
  • they were very quickly broken down by the body and couldn't get across the blood-brain barrier,
  • cellular barrier that prevents drugs and other molecules from entering the brain
  • 'That's useless. I mean, who wants to drill holes in people's heads?
  • designed a smaller version of the molecule
  • Not only is it stable but it can cross the blood-brain barrier
  • added bonus is it can move from the gut into the blood, so it can be taken in pill form
  • reported similar but less dramatic results in a smaller group of old rats. In this study the old rats
  • tested the drug on several dozen rats treated with scopolamine, a chemical that interferes with a neurotransmitter critical to learning and memory.
  • a rat treated with scopolamine will never learn the location of a submerged platform in a water tank, orienting with cues outside the tank
  • After receiving the WSU drug, however, all of the rats did, whether they received the drug directly in the brain, orally, or through an injection.
  • statistically valid, additional studies with larger test groups will be necessary to fully confirm the finding.
  • bench assays using living nerve cells to monitor new neuronal connections
  • Dihexa to be seven orders of magnitude more powerful than BDNF, which has yet to be effectively developed for therapeutic use
Mars Base

Study: Adolescent marijuana use leaves lasting mental deficits - 0 views

medicalxpress.com/...scent-pot-mental-deficits.html

scibyte61

shared by Mars Base on 29 Aug 12 - No Cached
  • The persistent, dependent use of marijuana before age 18 has been shown to cause lasting harm to a person's intelligence, attention and memory, according to an international research team.
  • a long-range study cohort of more than 1,000
  • psychologist who was not involved in the research, said this study is among the first to distinguish between cognitive problems the person might have had before taking up marijuana, and those that were apparently caused by the drug
  • ...4 more annotations...
  • The study has followed a group of 1,037 children
  • from birth to age 38
  • At age 38, all of the study participants were given a battery of psychological tests to assess memory, processing speed, reasoning and visual processing
  • Friends and relatives routinely interviewed as part of the study were more likely to report that the persistent cannabis users had attention and memory problems such as losing focus and forgetting to do tasks.
Mars Base

Music has big brain benefits compared to other leisure pursuits - 0 views

medicalxpress.com/...ig-brain-benefits-leisure.html

GrabBag MusicalScience

shared by Mars Base on 20 Jul 12 - No Cached
  • Musical instrumental training, when compared to other activities, may reduce the effects of memory decline and cognitive aging
  • second study
  • which confirms and refines findings from an original study
  • ...7 more annotations...
  • that revealed that musicians with at least 10 years of instrumental musical training remained cognitively sharp in advanced age
  • range of cognitive benefits, including memory, was sustained for musicians between the ages of 60-80 if they played for at least 10 years throughout their life
  • While years of playing music were the best indication of enhanced cognition in advanced age, the results revealed different sensitive periods for cognitive development across the lifespan
  • before age nine, predicted verbal working memory functions
  • Sustained musical activity in advanced age predicted other non-verbal abilities involving visuospatial judgment, suggesting it is never too late to be musically active
  • Continued musical activity in advanced age also appeared to buffer lower educational levels
  • to obtain optimal results, individuals should start musical training before age nine, play at least 10 years or more and if possible, keep playing for as long as possible over the age of 60.
Mars Base

Global "Selfie" to Be Beamed to Outer Space - 0 views

news.nationalgeographic.com/...fie-message-new-horizons-space

scibyte131 NewHorizons NewHorizonsMessage

shared by Mars Base on 18 May 14 - No Cached
  • This summer, you will get that chance to send a message to other worlds.
  • leaders of an initiative called New Horizons Message Initiative, announced
  • at the Smithsonian Future Is Here Festival in Washington, D.C., that NASA has agreed to upload a digital crowd-sourced message to the New Horizons spacecraft
  • ...30 more annotations...
  • The content of the message will be determined by whomever wants to participate in the planet-wide project
  • The message itself will be transmitted sometime after New Horizons does a flyby of Pluto in 2015 and sends back the scientific data that it collects
  • If all goes according to plan, New Horizons will become the fifth man-made object to travel beyond the solar system—after Pioneers 10 and 11 and Voyagers 1 and 2.
  • it's the only one of the five not to launch with a message for any alien travelers it might encounter along the way
  • The Pioneer spacecrafts bore plaques on their sides, and the Voyagers each carried golden records (and the means to play them).
  • When New Horizons' journey was being planned
  • other missions had been scrapped and the budget was extremely tight
  • didn't have the bandwidth for
  • the message
  • . "Now
  • It doesn't cost massive amounts because there's no hardware, just uplinking ones and zeroes
  • Lomberg, who worked closely with Carl Sagan on the Voyager golden record in 1977, had an epiphany last year about sending the message digitally
  • In September 2013, Lomberg launched a website with a petition to NASA. By February 2014, 10,000 people from over 140 countries had signed it.
  • Lomberg approached Stern, who advised him that NASA would need evidence of public support
  • This message will be very different from the one Lomberg designed with Sagan almost 40 years ago
  • The 21st-century version will be a global self-portrait, pieced together by many willing hands
  • Anyone on Earth will be able to upload potential content (images, sounds, software—the formats haven't been finalized)
  • Then everyone will be able to vote on what to include
  • "Our team is going to provide the overall architecture of the message," says Lomberg, "but we'll try to keep ourselves open to what we will send."
  • , a National Geographic emerging explorer
  • will have to figure out how to wrangle a planet's worth of opinions into the roughly 100 MB of memory New Horizons will have available on its computer.
  • the project will officially launch August 25, the final file may not be sent for several years
  • The New Horizons computer won't have any room in its memory until the data from Pluto are transmitted back to Earth, which could take more than a year
  • "The spacecraft is so far away," says Lomberg, "that download times are like dial-up Internet."
  • Pluto may not be the final mission target
  • hopes that the spacecraft will have a shot at a flyby of another object in the Kuiper Belt of the solar system
  • If that happens, the message upload will be delayed
  • As long as the spacecraft is healthy and the radio is working," he says, "there's no particular rush to send it
  • cosmic radiation may eventually corrupt the spacecraft's electronic memory
  • The New Horizons message won't last nearly as long as the metal missives attached to Pioneer and Voyager will
Mars Base

Numbers Games Devised to Aid People with "Dyscalculia": Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte78 Dyscalculia

shared by Mars Base on 19 Jan 13 - No Cached
  • By developing treatments for dyscalculia
  • to test competing theories about the cognitive basis of numeracy. If,
  • dyscalculia is at heart a deficiency of basic number sense and not of memory, attention or language, as others have proposed, then nurturing the roots of number sense should help dyscalculics
  • ...12 more annotations...
  • It may be the case that what these kids need is just much more practice than the rest of us
  • starts with a game involving a number line
  • “What is the number that is right in the middle between 200 and 800? Do you know it?
  • A classic sign of dyscalculia is difficulty in grasping the place-value system,
  • A soft computer voice tells Christopher to “find the number and click it
  • The game involves zooming in and zooming out to rescale the number line
  • talks through each move — a strategy that Babtie encourages
  • but it takes him more than a minute to locate 210. His classmates, meanwhile, are learning to multiply two-digit numbers.
  • Butterworth
  • made his name probing obscure speech and language disorders
  • tested 31 eight- and nine-year-old children who were near the bottom of their class in mathematics but did well enough in other subjects.
  • Compared with normal children and those with dyslexia, the dyscalculic children struggled on almost every numerical task, yet were average on tests of reading comprehension, memory and IQ.
Mars Base

New drug reverses loss of brain connections in Alzheimer's disease - 0 views

medicalxpress.com/...rses-loss-brain-alzheimer.html

scibyte99 Alzheimer

shared by Mars Base on 18 Jun 13 - No Cached
  • The first experimental drug to boost brain synapses lost in Alzheimer's disease
  • combines two FDA-approved medicines to stop the destructive cascade of changes in the brain that destroys the connections between neurons, leading to memory loss and cognitive decline.
  • The decade-long study
  • ...21 more annotations...
  • shows that NitroMemantine can restore synapses, representing the connections between nerve cells (neurons) that have been lost during the progression of Alzheimer's in the brain
  • These findings actually mean that you might be able to intercede not only early but also a bit later
  • Alzheimer's patient may be able to have synaptic connections restored even with plaques and tangles already in his or her brain.
  • study, conducted in animal models as well as brain cells derived from human stem cells,
  • team mapped the pathway that leads to synaptic damage in Alzheimer
  • found that amyloid beta peptides, which were once thought to injure synapses directly
  • actually induce the release of excessive amounts of the neurotransmitter glutamate from brain cells called astrocytes that are located adjacent to the nerve cells.
  • Normal levels of glutamate promote memory and learning, but excessive levels are harmful
  • Alzheimer's disease, excessive glutamate activates extrasynaptic receptors, designated eNMDA receptors
  • which get hyperactivated and in turn lead to synaptic loss
  • lab had previously discovered how a drug called memantine can be targeted to eNMDA receptors to slow the hyperactivity seen in Alzheimer's.
  • memantine's effectiveness has been limited.
  • memantine—a positively charged molecule—is repelled by a similar charge inside diseased neurons
  • memantine gets repelled from its intended eNMDA receptor target on the neuronal surface.
  • FDA approval of memantine in 2003
  • a fragment of the molecule nitroglycerin—a second FDA-approved drug commonly used to treat episodes of chest pain or angina in people with coronary heart disease—could bind to another site that the Lipton group discovered on NMDA receptors.
  • memantine rather selectively binds to eNMDA receptors, it also functions to target nitroglycerin to the receptor
  • by combining the two, Lipton's lab created a new, dual-function drug
  • researchers developed 37 derivatives of the combined drug before they found one that worked
  • By shutting down hyperactive eNMDA receptors on diseased neurons, NitroMemantine restores synapses between those neurons
  • NitroMemantine brings the number of synapses all the way back to normal within a few months of treatment in mouse models of Alzheimer's disease. In fact, the new drug really starts to work within hours
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