Neuroscience

Articles and news from the latest research reports.

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Computer Simulations Shed New Light On How The Immune System Works
Researchers at McGill University in Montreal have developed computer simulations that better explain how a person’s immune cells can detect foreign antigens and fight infections.
In an effort to determine exactly how the body’s natural defenses are able to sort through large amounts of similar-looking proteins in order to locate and eliminate harmful invaders, physics professor Paul François and graduate student Jean-Benoît Lalanne used computational tools to study how the process works.
They discovered that the antigen-fighting process is related to the phenomenon of biochemical adaptation – a mechanism that enables organisms to cope with a variety of different environmental conditions. According to the authors of the study, their work could prove essential insight into AIDS and other immune diseases.
“For immune cells, singling out foreign proteins is like looking for a needle in a haystack – where the needle may look very much like a straw, and where some straws may also look very much like a needle,” François said. “Our approach provides a simpler theoretical framework and understanding of what happens” as the immune cells sort through that “haystack” in search of foreign antigens and to trigger the body’s immune response.
The researchers’ computer simulation used an algorithm that was inspired by Darwinian evolution, the university explained. The algorithm randomly creates mathematical models of biochemical networks, and then scores them by comparing their properties to those of an actual immune system. The highest-rated networks are duplicated in the next generation and mutated, a process that is repeated until the networks achieve a perfect score.
“Our model shares many similarities with real immune networks,” explained François. “Strikingly, the simplest evolved solution we found has both similar characteristics and some of the blind spots of real immune cells we studied in a previous collaborative study with the groups of Grégoire Altan-Bonnet (Memorial Sloane Kettering, New York), Eric Siggia (Rockefeller University, New York) and Massimo Vergassola (Pasteur Institute, Paris).”
The Natural Sciences and Engineering Research Council of Canada and the Human Frontier Science Program provided funding for the research, which was published in a recent edition of the journal Physical Review Letters.

Computer Simulations Shed New Light On How The Immune System Works

Researchers at McGill University in Montreal have developed computer simulations that better explain how a person’s immune cells can detect foreign antigens and fight infections.

In an effort to determine exactly how the body’s natural defenses are able to sort through large amounts of similar-looking proteins in order to locate and eliminate harmful invaders, physics professor Paul François and graduate student Jean-Benoît Lalanne used computational tools to study how the process works.

They discovered that the antigen-fighting process is related to the phenomenon of biochemical adaptation – a mechanism that enables organisms to cope with a variety of different environmental conditions. According to the authors of the study, their work could prove essential insight into AIDS and other immune diseases.

“For immune cells, singling out foreign proteins is like looking for a needle in a haystack – where the needle may look very much like a straw, and where some straws may also look very much like a needle,” François said. “Our approach provides a simpler theoretical framework and understanding of what happens” as the immune cells sort through that “haystack” in search of foreign antigens and to trigger the body’s immune response.

The researchers’ computer simulation used an algorithm that was inspired by Darwinian evolution, the university explained. The algorithm randomly creates mathematical models of biochemical networks, and then scores them by comparing their properties to those of an actual immune system. The highest-rated networks are duplicated in the next generation and mutated, a process that is repeated until the networks achieve a perfect score.

“Our model shares many similarities with real immune networks,” explained François. “Strikingly, the simplest evolved solution we found has both similar characteristics and some of the blind spots of real immune cells we studied in a previous collaborative study with the groups of Grégoire Altan-Bonnet (Memorial Sloane Kettering, New York), Eric Siggia (Rockefeller University, New York) and Massimo Vergassola (Pasteur Institute, Paris).”

The Natural Sciences and Engineering Research Council of Canada and the Human Frontier Science Program provided funding for the research, which was published in a recent edition of the journal Physical Review Letters.

Filed under immune system antigens immune cells biochemical adaptation biochemical networks neuroscience science

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Unusual Antibodies in Cows Suggest New Ways to Make Therapies for People 
Humans have been raising cows for their meat, hides and milk for millennia. Now it appears that the cow immune system also has something to offer. A new study led by scientists from The Scripps Research Institute (TSRI) focusing on an extraordinary family of cow antibodies points to new ways to make human medicines.
“These antibodies’ structure and their mechanism for creating diversity haven’t been seen before in other animals’ antibodies,” said Vaughn V. Smider, assistant professor of cell and molecular biology at TSRI and principal investigator for the study, which appears as the cover story in the June 6, 2013 issue of the journal Cell.
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Unusual Antibodies in Cows Suggest New Ways to Make Therapies for People

Humans have been raising cows for their meat, hides and milk for millennia. Now it appears that the cow immune system also has something to offer. A new study led by scientists from The Scripps Research Institute (TSRI) focusing on an extraordinary family of cow antibodies points to new ways to make human medicines.

“These antibodies’ structure and their mechanism for creating diversity haven’t been seen before in other animals’ antibodies,” said Vaughn V. Smider, assistant professor of cell and molecular biology at TSRI and principal investigator for the study, which appears as the cover story in the June 6, 2013 issue of the journal Cell.

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Filed under cows immune system antibodies medicine science

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Big Multiple Sclerosis Breakthrough

Phase 1 trial safely resets patients’ immune systems, reduces attack on myelin protein

A phase 1 clinical trial for the first treatment to reset the immune system of multiple sclerosis (MS) patients showed the therapy was safe and dramatically reduced patients’ immune systems’ reactivity to myelin by 50 to 75 percent, according to new Northwestern Medicine research.

In MS, the immune system attacks and destroys myelin, the insulating layer that forms around nerves in the spinal cord, brain and optic nerve. When the insulation is destroyed, electrical signals can’t be effectively conducted, resulting in symptoms that range from mild limb numbness to paralysis or blindness.

“The therapy stops autoimmune responses that are already activated and prevents the activation of new autoimmune cells,” said Stephen Miller, the Judy Gugenheim Research Professor of Microbiology-Immunology at Northwestern University Feinberg School of Medicine. “Our approach leaves the function of the normal immune system intact. That’s the holy grail.”

Miller is the co-senior author of a paper on the study, which was published June 5 in the journal Science Translational Medicine. The study is a collaboration between Northwestern’s Feinberg School, University Hospital Zurich in Switzerland and University Medical Center Hamburg-Eppendorf in Germany. 

The human trial is the translation of more than 30 years of preclinical research in Miller’s lab.   

In the trial, the MS patients’ own specially processed white blood cells were used to stealthily deliver billions of myelin antigens into their bodies so their immune systems would recognize them as harmless and develop tolerance to them.    

Current therapies for MS suppress the entire immune system, making patients more susceptible to everyday infections and higher rates of cancer.

While the trial’s nine patients — who were treated in Hamburg, Germany — were too few to statistically determine the treatment’s ability to prevent the progression of MS, the study did show patients who received the highest dose of white blood cells had the greatest reduction in myelin reactivity. 

The primary aim of the study was to demonstrate the treatment’s safety and tolerability. It showed the intravenous injection of up to 3 billion white blood cells with myelin antigens caused no adverse affects in MS patients. Most importantly, it did not reactivate the patients’ disease and did not affect their healthy immunity to real pathogens.

As part of the study, researchers tested patients’ immunity to tetanus because all had received tetanus shots in their lifetime. One month after the treatment, their immune responses to tetanus remained strong, showing the treatment’s immune effect was specific only to myelin.   

The human safety study sets the stage for a phase 2 trial to see if the new treatment can prevent the progression of MS in humans. Scientists are currently trying to raise $1.5 million to launch the trial, which has already been approved in Switzerland. Miller’s preclinical research demonstrated the treatment stopped the progression of relapsing-remitting MS in mice.

“In the phase 2 trial we want to treat patients as early as possible in the disease before they have paralysis due to myelin damage.” Miller said. “Once the myelin is destroyed, it’s hard to repair that.”

In the trial, patients’ white blood cells were filtered out, specially processed and coupled with myelin antigens by a complex GMP manufacturing process developed by the study co-senior authors, Roland Martin, Mireia Sospedra, and Andreas Lutterotti and their team at the University Medical Center Hamburg-Eppendorf. Then billions of these dead cells secretly carrying the myelin antigens were injected intravenously into the patients. The cells entered the spleen, which filters the blood and helps the body dispose of aging and dying blood cells. During this process, the immune cells start to recognize myelin as a harmless and immune tolerance quickly develops. This was confirmed in the patients by immune assays developed and carried out by the research team in Hamburg.  

This therapy, with further testing, may be useful for treating not only MS but also a host of other autoimmune and allergic diseases simply by switching the antigens attached to the cells. Previously published preclinical research by Miller showed the therapy’s effectiveness for type 1 diabetes and airway allergy (asthma) and peanut allergy.

The MS human trial relates directly to Miller’s recently published research in mice in which he used nanoparticles — rather than a patient’s white blood cells — to deliver the myelin antigen. Using a patient’s white blood cells is a costly and labor-intensive procedure. Miller’s study showed the nanoparticles, which are potentially cheaper and more accessible to a general population, could be as effective as the white blood cells as delivery vehicles. This nanoparticle technology has been licensed to Cour Pharmaceutical Development Company and is in preclinical development.

Miller’s research represents several pillars of Northwestern’s Strategic Plan by discovering new ways to treat disease in the biomedical sciences and translating those discoveries into ideas and products that make the world a better place for everyone.

(Source: northwestern.edu)

Filed under MS immune system myelin antigens white blood cells medicine science

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PD-Like Sleep and Motor Problems Observed in α-Synuclein Mutant Mice

The presence of Lewy bodies in nerve cells, formed by intracellular deposits of the protein α-synuclein, is a characteristic pathologic feature of Parkinson’s Disease (PD). In the quest for an animal model of PD that mimics motor and non-motor symptoms of human PD, scientists have developed strains of mice that overexpress α-synuclein. By studying a strain of mice bred to overexpress α-synuclein via the Thy-1 promoter, scientists have found these mice develop many of the age-related progressive motor symptoms of PD and demonstrate changes in sleep and anxiety. Their results are published in the latest issue of Journal of Parkinson’s Disease.

PD is the second most common neurodegenerative disorder in the United States, affecting approximately one million Americans and five million people worldwide. Its prevalence is projected to double by 2030. The most obvious symptoms are movement-related, such as involuntary shaking and muscle stiffness; non-motor symptoms, such as increases in anxiety and sleep disturbances, can appear prior to the onset of motor symptoms. Although the drug levodopa can relieve some symptoms, there is no cure – intensifying the pressure to find an animal model that can help clarify the pathological processes underlying human PD and find new medications to treat the pathology and/or relieve symptoms. 

Investigators at the National Institute on Aging compared wild type mice with specially bred mice that were transgenic for the A53T mutation of the human α-synuclein (SNCA) gene under the control of a human thymus cell antigen 1, theta (THY-1) promoter. As the mice aged, their motor performance on a rotarod test (which measures how long the mouse can remain on a rotating rod) became impaired and the length of their strides were significantly shorter than the wild type control mice.

The study also found that SNCA mice displayed fragmented nighttime activity patterns compared to wild type controls and appeared to have a reduced overall sleep time. “Despite the prevalence of abnormal sleep patterns in PD, very few studies to date have outlined sleep disturbances in animal models of PD,” says Sarah M. Rothman, PhD, a researcher with the National Institute on Aging, in Baltimore, MD.

Many PD patients typically show an increase in anxiety and depression, and in this respect the SNCA mouse model did not replicate the human condition. SNCA mice displayed an early and significant decrease in anxiety-like behavior that persisted throughout their lifespan, as shown by both open field and elevated plus maze tests (in which mice have the choice of spending time in open or closed arms of a maze). Other rodent models that utilize changes in expression of α-synuclein have also reported lower anxiety levels. The authors suggest that higher levels of serotonin found in the hypothalamus of the SNCA mice may be associated with the reduced anxiety observed.

The authors say it is important to remember that the SNCA “model utilizes the presence of a mutation that only occurs very rarely in PD. While all PD patients display α-synuclein pathology, they do not all express the mutated form of the protein,” says Dr. Rothman.

(Source: alphagalileo.org)

Filed under parkinson's disease α-synuclein sleep anxiety serotonin animal model motor performance neuroscience science

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By trying it all, predatory sea slug learns what not to eat
Researchers have found that a type of predatory sea slug that usually isn’t picky when it comes to what it eats has more complex cognitive abilities than previously thought, allowing it to learn the warning cues of dangerous prey and thereby avoid them in the future.
The research appears in the Journal of Experimental Biology.
Pleurobranchaea californica is a deep-water species of sea slug found off the west coast of the United States. It has a relatively simple neural circuitry and set of behaviors. It is a generalist feeder, meaning, as University of Illinois professor of molecular and integrative physiology and leader of the study Rhanor Gillette put it, that members of this species “seem to try anything once.”
Another sea slug species, Flabellina iodinea, commonly known as the Spanish shawl because of the orange outgrowths called cerata that cover its purple back, also lives off the west coast. Unlike Pleurobranchaea, however, the Spanish shawl eats only one type of food, an animal called Eudendrium ramosum. According to Gillette, the Spanish shawl digests the Eudendrium’s entire body except for its embryonic, developing stinging cells. The Spanish shawl instead transports these stinging cells to its own cerata where they mature, thereby co-opting its victim’s body parts for its own defense.
The story of Gillette’s Pleurobranchaea-Flabellina research began with a happy accident that involved showing a lab visitor Pleurobranchaea’s penchant for predation.
“I had a Pleurobranchaea in a small aquarium that we were about to do a physiological experiment with, and my supplier from Monterey had just sent me these beautiful Spanish shawls,” Gillette said. “So I said to the visitor, ‘Would you like to see Pleurobranchaea eat another animal?’”
Gillette placed the Spanish shawl into the aquarium. The Pleurobranchaea approached, smelled, and bit the purple and orange newcomer. However, the Flabellina’s cerata stung the Pleurobranchaea, the Spanish shawl was rejected and left to do its typical “flamenco dance of escape,” and Pleurobranchaea also managed to escape with an avoidance turn.
Some minutes later, his curiosity piqued, Gillette placed the Spanish shawl back into the aquarium with the Pleurobranchaea. Rather than try to eat the Spanish shawl a second time, the Pleurobranchaea immediately started its avoidance turn. (Watch a video of this interaction.)
“I had never seen that before! We began testing them and found that they were learning the odor of the Spanish shawl very specifically and selectively,” Gillette said.
Gillette and his team later replicated that day’s events by placing a Pleurobranchaea in a training arena 12-15 centimeters from a Spanish shawl, then recorded the Pleurobranchaea’s behavior. They returned the Pleurobranchaea to the arena for four more trials in 20-minute intervals, then repeated the procedure 24 and 72 hours later.
In the experiments, those Pleurobranchaea whose feeding thresholds were too high (meaning they were already full) or too low (they were extremely hungry) would either not participate or completely consume the Spanish shawl, respectively. Those that were hungry, but not ravenously so, continued to exhibit the avoidance-turn behavior when placed with the Spanish shawl even 72 hours later.
This showed that Pleurobranchaea was selective in its food choices, but only on a case-by-case basis; the sea slugs already trained to avoid the Spanish shawl would readily eat a species closely related to Flabellina called Hermissenda crassicornis.
Such behaviors come in handy in Pleurobranchaea’s natural environment, Gillette said.
“If you’re a generalist like Pleurobranchaea, it’s highly strategic and advantageous to learn what’s good and what’s not good so you can decide whether or not to take the risk or of attacking certain types of prey,” he said.
These findings show that the “simple” Pleurobranchaea is much more complex than originally thought.
“We already knew the neuronal circuitry that mediates this kind of decision,” Gillette said. “Finding this highly selective type of learning enlarges our perspective of function, in terms of the animal’s ability to make cost-benefit decisions that place it on a rather higher plane of cognitive ability than previously thought for many sea slugs.”

By trying it all, predatory sea slug learns what not to eat

Researchers have found that a type of predatory sea slug that usually isn’t picky when it comes to what it eats has more complex cognitive abilities than previously thought, allowing it to learn the warning cues of dangerous prey and thereby avoid them in the future.

The research appears in the Journal of Experimental Biology.

Pleurobranchaea californica is a deep-water species of sea slug found off the west coast of the United States. It has a relatively simple neural circuitry and set of behaviors. It is a generalist feeder, meaning, as University of Illinois professor of molecular and integrative physiology and leader of the study Rhanor Gillette put it, that members of this species “seem to try anything once.”

Another sea slug species, Flabellina iodinea, commonly known as the Spanish shawl because of the orange outgrowths called cerata that cover its purple back, also lives off the west coast. Unlike Pleurobranchaea, however, the Spanish shawl eats only one type of food, an animal called Eudendrium ramosum. According to Gillette, the Spanish shawl digests the Eudendrium’s entire body except for its embryonic, developing stinging cells. The Spanish shawl instead transports these stinging cells to its own cerata where they mature, thereby co-opting its victim’s body parts for its own defense.

The story of Gillette’s Pleurobranchaea-Flabellina research began with a happy accident that involved showing a lab visitor Pleurobranchaea’s penchant for predation.

“I had a Pleurobranchaea in a small aquarium that we were about to do a physiological experiment with, and my supplier from Monterey had just sent me these beautiful Spanish shawls,” Gillette said. “So I said to the visitor, ‘Would you like to see Pleurobranchaea eat another animal?’”

Gillette placed the Spanish shawl into the aquarium. The Pleurobranchaea approached, smelled, and bit the purple and orange newcomer. However, the Flabellina’s cerata stung the Pleurobranchaea, the Spanish shawl was rejected and left to do its typical “flamenco dance of escape,” and Pleurobranchaea also managed to escape with an avoidance turn.

Some minutes later, his curiosity piqued, Gillette placed the Spanish shawl back into the aquarium with the Pleurobranchaea. Rather than try to eat the Spanish shawl a second time, the Pleurobranchaea immediately started its avoidance turn. (Watch a video of this interaction.)

“I had never seen that before! We began testing them and found that they were learning the odor of the Spanish shawl very specifically and selectively,” Gillette said.

Gillette and his team later replicated that day’s events by placing a Pleurobranchaea in a training arena 12-15 centimeters from a Spanish shawl, then recorded the Pleurobranchaea’s behavior. They returned the Pleurobranchaea to the arena for four more trials in 20-minute intervals, then repeated the procedure 24 and 72 hours later.

In the experiments, those Pleurobranchaea whose feeding thresholds were too high (meaning they were already full) or too low (they were extremely hungry) would either not participate or completely consume the Spanish shawl, respectively. Those that were hungry, but not ravenously so, continued to exhibit the avoidance-turn behavior when placed with the Spanish shawl even 72 hours later.

This showed that Pleurobranchaea was selective in its food choices, but only on a case-by-case basis; the sea slugs already trained to avoid the Spanish shawl would readily eat a species closely related to Flabellina called Hermissenda crassicornis.

Such behaviors come in handy in Pleurobranchaea’s natural environment, Gillette said.

“If you’re a generalist like Pleurobranchaea, it’s highly strategic and advantageous to learn what’s good and what’s not good so you can decide whether or not to take the risk or of attacking certain types of prey,” he said.

These findings show that the “simple” Pleurobranchaea is much more complex than originally thought.

“We already knew the neuronal circuitry that mediates this kind of decision,” Gillette said. “Finding this highly selective type of learning enlarges our perspective of function, in terms of the animal’s ability to make cost-benefit decisions that place it on a rather higher plane of cognitive ability than previously thought for many sea slugs.”

Filed under pleurobranchaea californica sea slug cognition learning neural circuitry neuroscience science

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Diabetes drug shows promise in treatment of neurodegenerative disease

Researchers in Spain have found that a drug used to control Type II diabetes can help repair the spinal cords of mice suffering from the inherited disease adrenoleukodystrophy which, untreated, leads eventually to a paralysis, a vegetative state and death. They believe that their findings may be relevant to other neurodegenerative diseases.  A Phase II trial will be starting shortly. The research is published simultaneously on line in the journal Brain.

A drug used to control Type II diabetes can help repair the spinal cords of mice suffering from the inherited disease adrenoleukodystrophy which, untreated, leads eventually to a paralysis, a vegetative state and death. This is an important step along the road to the development of a therapy for the human disease for which current treatment options are scarce and only partially effective, the annual conference of the European Society of Human Genetics will hear tomorrow (Sunday).

Professor Aurora Pujol, a research professor for the Catalan Government Research Body ICREA, working as Director of the Neurometabolic Diseases Laboratory at IDIBELL, Barcelona, Spain, investigated the role of mitochondria, the power plant of the cell, in adrenoleukodystrophy, a disease caused by the inactivation of the ABCD1 transporter of fatty acids in peroxisomes.  This inactivation leads to the accumulation of fatty acids in organs and blood plasma, and causes spinal cord degeneration.

“ABCD1 is a protein located in the peroxisomes, compartments of the cell that detoxify chemicals and lipids, and thus the implication of mitochondria in such a disease was not obvious.  But we knew from recent research that oxidative stress – where there is increased production of chemically active oxygen-containing molecules, and also significant decrease in the effectiveness of the body’s antioxidant defences – was involved.  We also knew that bioenergetic failure appeared before disease symptoms.  We therefore decided to investigate the role of the mitochondria”, Professor Pujol will say.

The group of diseases known as leukodystrophies are characterised by progressive loss of the myelin sheath, the fatty covering that acts as an insulator around nerve fibres.  Damage to the myelin sheath impairs the conduction of signals in the affected nerves and leads to locomotor problems. 

“We knew that early oxidative damage and bioenergetic dysfunction underlay the late onset degeneration of nerve fibres observed in the mouse model of X-linked adrenoleukodystrophy (X-ALD), the most frequently inherited leukodystrophy, so we looked at mitochondria for further clues.  We found that the X-ALD mice showed a loss of mitochondria at 12 months of age, prior to disease symptoms, so this could not be a consequence of the disease, but rather a contributing factor.  We also knew that the pathway involved in the mitochondrial loss could be treated by the use of the diabetes drug pioglitazone, so we decided to test its effect in the mice”, Professor Pujol will say.

Pioglitazone halted the nerve fibre degeneration by preventing the loss of mitochondria, and inhibiting metabolic failure and oxidative stress in the treated mice, and hence also halted locomotor disabilities.   The researchers were able to prove this both through analysis of spinal cords post mortem, and in vivo by putting the mice through a number of physical tests.

Although X-ALD is a relatively rare disease  with a minimum incidence of 1 in 17 000 males, there are other neurodegenerative disorders caused by myelin sheath degeneration, for example multiple sclerosis, and many others where impaired bioenergetics combined with oxidative stress and degeneration of axons are known to be involved.  The latter category of disease includes Parkinson’s, Huntington’s, and Alzheimer’s.  “It is possible that our findings may be relevant to these conditions as well,” says Professor Pujol.

“Following on from these promising results, together with Professor Patrick Aubourg from the Hôpital Bicêtre, Paris, we will shortly be starting a multi-centre phase II clinical trial of pioglitazone in adult patients suffering from a late onset variant of adrenoleukodystrophy.   Our research has shown that it will be feasible to monitor the biological effects of the drug by looking for biomarkers of oxidative damage in blood cells or plasma.  We are happy to have made a contribution to finding a simple and effective treatment to a group of devastating diseases”, she will conclude.

(Source: alphagalileo.org)

Filed under adrenoleukodystrophy leukodystrophies myelin sheath type ii diabetes fatty acids neuroscience science

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Over-produced autism gene alters synapses, affects learning and behavior in mice

A gene linked to autism spectrum disorders that was manipulated in two lines of transgenic mice produced mature adults with irreversible deficits affecting either learning or social interaction.

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The findings, published in the May 29 issue of the Journal of Neuroscience, have implications for potential gene therapies but they also suggest that there may be narrow windows of opportunity to be effective, says principal investigator Philip Washbourne, a professor of biology and member of the University of Oregon’s Institute of Neuroscience.

The research, reported by an 11-member team from three universities, targeted the impacts of alterations in the gene neuroligin 1 — one of many genes implicated in human autism spectrum disorders — to neuronal synapses in the altered mice during postnatal development and as they entered adulthood. One group over-expressed the normal gene, the other a mutated version.

Mice with higher-than-normal levels of the normal gene after a month had skewed synapses at maturity. Many were larger, appearing more mature, than normal. In these mice, Washbourne said, there were clear cognitive problems. “Behavior was just not normal. They didn’t learn very well, and they were slower to learn, but their social behavior was not impacted.”

Mice over-producing a mutated version of the gene reached adulthood with structurally immature synapses. “They were held back in development and behavior — the way they behave in terms of learning and memory, in terms of social interaction,” he said. “These were adult mice, three months old, but they behaved like normal mice at four weeks old. We saw arrested development. Learning is a little bit better, they are more flexible just like young mice, they learn faster, but their social interaction is off. To us, this looked more like Asperger’s syndrome.

"So with the same gene, doing two different manipulations — overexpressing the normal form or overexpressing a mutated form — we’ve gone to two different ends of the autism spectrum," said Washbourne, whose lab focuses on basic synapse formation and what goes wrong in relationship to autism. Work has been done in both mice and zebra fish.

"We made these mice so that we can turn the genes on and off as we want," Washbourne said. "Using an antibiotic, doxycycline, it turns off these altered genes that we inserted into their chromosomes. While on doxycycline, the mice are absolutely normal.”

However, if the inserted gene was turned off after the completion of development, mice still showed altered synapses and behavior. This result suggests that any kind of gene therapy may have to be applied to individuals with autism early on.

Effects seen in the social behavior of mice with the mutated gene, he said, are not unlike observations reported by parents of many autistic children. While normal mice prefer to engage with new mice entering their world rather than familiar others, or even a new inanimate object, these mice split their time equally. “It’s not a deficit in memory regarding which mouse is which, it’s more a weighting of their interaction. Does that mean they are autistic? I don’t know, but if you talk to parents of autistic children, one of the frustrating things they report is that their children treat complete strangers in exactly the same way that they treat them.”

While the findings provide new insights, Washbourne said, any translation into treatment could be decades away. “A problem with autism is there are many different genes potentially involved. It could be that some day, if you are diagnosed with autism, a mouth swab might allow for the identification of the exact gene that is mutated and allow for targeted therapy,” he said. “Genome sequencing already has turned up subtle mutations in lots of genes. Autism might be like cancer, with hundreds of potential combinations of faulty genes.”

(Source: uonews.uoregon.edu)

Filed under ASD autism asperger's syndrome neurons learning neuroligin 1 neuroscience science

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The protein profile of restless leg syndrome

A protein profile of people with restless leg syndrome (RLS), identifies factors behind disrupted sleep, cardiovascular dysfunction and pain finds research in BioMed Central’s open access journal Fluids and Barriers of the CNS. The research gives insights into the disorder, and could be useful in the development of new treatments.

It is not completely clear what causes RLS, also known as Willis Ekbom disease (WED), but in some people it is associated with iron deficiency in the brain, kidney failure, or low levels of the ‘pleasure’ neurotransmitter dopamine. It can also occur during pregnancy. It affects between 5 and 10% of the population and symptoms, which can range in severity, including sleep deprivation and decreased ability to work can lead to a reduction in quality of life. It is also a risk factor for cardiovascular disease.

Comparing the cerebral spinal fluid (CSF) of women with and without RLS, researchers from the US and Korea discovered  there was a significantly altered level of six specific proteins with RLS. Dr Stephanie Patton from Penn State University who led this study explained, “Our results reveal a protein profile in the RLS/WED CSF that is consistent with iron deficiency, dopamine dysregulation and inflammation.”

These proteins include a protein which transports vitamin D into cells and is involved in the regulation of dopamine levels, cystatin C – a biomarker for pain found in people with sciatica and during labor, and a neuromodulator (PTGDS) known to be involved in sleep disturbances. Levels of apolipoprotein (Apo) A1 were lower with RLS and may be related to the increased risk of cardiovascular disease.

The importance of iron’s role in RLS is highlighted by the presence of B-hemoglobin in the CSF of women with RLS, while levels of a glycoprotein (AGP) were reduced. AGP is involved in response to inflammatory damage and requires the presence of iron for it to be protective.

Dr Stephanie Patton continued, “Although a small study, this CSF protein profile is consistent with observed neuropathological findings and supports existing hypotheses about the biology behind RLS/WED, which could prove clinically important in developing new treatments.”

(Source: alphagalileo.org)

Filed under restless leg syndrome willis ekbom disease iron deficiency dopamine proteins neuroscience science

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Unborn babies ‘practise’ facial expressions in the womb

Unborn babies ‘practise’ facial expressions of pain in the womb, according to a study published today.

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The researchers from Durham and Lancaster Universities suggest that fetuses’ ability to show a “pain” facial expression is a developmental process which could potentially give doctors another index of the health of a fetus.

The study is published in the prestigious academic journal, PLOS ONE, and was part funded by the Economic and Social Research Council (ESRC) and Durham University.

The study extends the findings of previous work demonstrating that the facial expressions of healthy fetuses develop and become more complex during pregnancy resulting in fetuses being able to show recognisable facial expressions.

The 4D scans of 15 healthy fetuses showed that they develop from making very simple one-dimensional expressions at 24 weeks, such as moving their lips in order to form a “smile”, to complex multi-dimensional expressions which can be recognised as “pain” expressions, by the time the mother is 36 weeks into her pregnancy.

The researchers suggest this is an adaptive process which enables the unborn baby to prepare themselves for life after birth when they have to communicate, for example if they feel hungry or uncomfortable, by making grimaces or crying. 

The researchers used the video footage of 4D scans, observing repeatedly the facial expressions of eight female and seven male fetuses from the second to third trimester (24 to 36 weeks) of pregnancy.

Fetuses observed at 24 weeks gestation rarely showed a combination of facial movements which make up a ‘pain face’, such as lowering the eyebrows, wrinkling the nose and stretching the mouth. However, by 36 weeks gestation, a combination of at least four movements was seen rather more frequently, giving the impression that these older fetuses were capable of making a pain face.

Lead researcher Dr Nadja Reissland, of Durham University’s Department of Psychology, said: “It is vital for infants to be able to show pain as soon as they are born so that they can communicate any distress or pain they might feel to their carers and our results show that healthy fetuses ‘learn’ to combine the necessary facial movements before they are born.

“This suggests that we can determine the normal development of facial movements and potentially identify abnormal development too. This could then provide a further medical indication of the health of the unborn baby.

“It is not yet clear whether fetuses can actually feel pain, nor do we know whether facial expressions relate to how they feel. Our research indicates that the expression of fetal facial movements is a developmental process which seems to be related to brain maturation rather than being linked to feelings.”

Professor of Social Statistics at Lancaster University Brian Francis said: “Modern methods of data analysis enable the development of fetal pain faces to be clearly detected, with the complexity of facial movements making up a pain face increasing in the third trimester”.

Despite the advances in medical science, we still do not know very much about health indicators of fetal development or any warning signs of delayed or abnormal progress in the womb.

It is hoped that further research will test whether the development of facial expressions is delayed if fetuses experience unhealthy conditions in the womb, such as effects of smoking or alcohol, or where the fetus is undergoing invasive procedures.

(Source: dur.ac.uk)

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Research unveils insight into a debilitating brain disease

From the neurons that enable thought to the keratinocytes that make toenails grow-a complex canopy of sugar molecules, commonly known as glycans, envelop every living cell in the human body.

These complex carbohydrate chains perform a host of vital functions, providing the necessary machinery for cells to communicate, replicate and survive. It stands to reason, then, that when something goes wrong with a person’s glycans, something goes wrong with them.

Now, researchers at the University of Georgia are learning how changes in normal glycan behavior are related to a rare but fatal lysosomal disease known as Niemann-Pick type C (NPC), a genetic disorder that prevents the body from metabolizing cholesterol properly. The findings were published recently in the PNAS Early Edition.

"We are learning that the problems associated with cholesterol trafficking in the cell lead to problems with glycans on the cell’s surface, and that causes a multitude of negative effects," said Geert-Jan Boons, professor of chemistry in the Franklin College of Arts and Sciences and researcher at UGA’s Complex Carbohydrate Research Center. "Now, for the first time, we can see what these problems are, which we hope will lead to a new understanding of diseases like NPC."

Because NPC patients are unable to metabolize cholesterol, the waxy substance begins to accumulate in the brain. This can lead to a host of serious problems, including neurodegeneration, which the researchers hypothesize may be caused by improper recycling of glycans on the surface of an NPC patient’s cells.

Glycans normally undergo a kind of recycling process when they enter the cell only to be returned to the surface recharged and ready to work. The researchers discovered that glycans in NPC cells do not do this.

"One of the secondary effects of NPC is the disruption of traffic pathways within the cell, and this can lead to altered recycling of glycans," said Richard Steet, associate professor of biochemistry and molecular biology and CCRC researcher. "The glycans come into the cell, but they won’t recycle back up to the cell’s surface where they must exist to function as receptors or ion channels."

"Basically, the machinery gets clogged up," Boons said.

Like downed phone lines and flooded roads in a thunderstorm, glycans get stuck inside the cell making communication and travel for these cells difficult or impossible. Without these basic abilities, the body’s motor, sensory and cognitive functions begin to suffer. This might explain why NPC patients suffer from such a wide variety of neurological and psychiatric disorders, such as uncoordinated limb movements, slurred speech, epilepsy, paralysis, psychosis, dementia and hallucinations.

The researchers made these observations in fibroblasts taken from diseased patients. These cells are most commonly found in connective tissues, and they play a vital role in wound healing. However, they hope to continue their investigation into the effects of NPC by studying glycan behavior in neural cells, which make up the human brain.

While they caution that much more work must be done, they hope that an improved understanding of the roles that glycans play in neural cells will lead to new therapeutics for NPC and other diseases like it.

"It is exciting to work on projects like these, because we believe glycobiology is the next frontier, the next level of complexity," Boons said. "The time is right for new discovery."

(Source: news.uga.edu)

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