"In neurons, transporting potassium ions from the cell is the natural mechanism of deactivation. Normally, an activated neuron will release them through passive potassium channels in the membrane.
With a light-activated, active potassium pump this process could be controlled precisely.""This would make KR2 a very effective off-switch for neurons.
Now, ways of integrating the pump into different types of cells need to be developed.""In combination with the light-activated Channelrhodopsin 2,
the KR2 potassium pump would then form a perfect pair of tools for the precise control of nerve cell activity,
During an epileptic seizure, the nerve cells in a specific area of the brain are activated suddenly in an excessive manner.
the researchers reproduced the hyperexcitability of epileptic neurons in mouse brains in vitro. They then injected GABA,
and that inhibits neurons, into this hyperactive region using the micropump. The scientists then observed that the compound not only stopped this abnormal activity in the target region,
and results from aberrant immune cells destroying the protective coating, called myelin, around nerve cells in the brain and spinal cord.
Without myelin, neural signals cannot be transmitted properly along nerves; over time, a patient's ability to walk, hold a cup
Current multiple sclerosis therapies aim to slow further myelin destruction by the immune system, but the Case Western Reserve team used a new approach to create new myelin within the nervous system.
Their work offers great promise of developing therapies that reverse disabilities caused by multiple sclerosis or similar neurological disorders."
and direct them to form new myelin. Our ultimate goal was to enhance the body's ability to repair itself."
both drugs prompted native OPCS to regenerate new myelin.""It was a striking reversal of disease severity in the mice,
a number of other disorders involve myelin loss or dysfunction including cerebral palsy, age-related dementia, optic neuritis and schizophrenia.
Any drugs developed that enhance myelination in multiple sclerosis also hold promise for benefiting these other disorders."
"The approach from Case Western Reserve University combines cutting-edge stem cell and drug screening technologies to develop new chemical therapeutics for myelin disorders,
which the immune system attacks the protective myelin sheath, a type of insulation that covers nerves, ultimately disrupting communication between the brain and the body and leading to nerve deterioration.
which create the myelin sheath. These two drugs, miconazole and clobetasol, were found to treat the source of the problem by reversing this process,
researchers discovered the therapeutic compounds for enhancing myelination from oligodendrocyte progenitor cells through screening a library of bioactive small molecules.
and clobetasol could promote myelination. Miconazole was found to function directly as a remyelinating drug with no effect on the immune system,
and direct them to form new myelin. Our ultimate goal was to enhance the body's ability to repair itself.""
"By studying mouse models, we first showed this gene is essential for the survival of neurons
""We also discovered the missing gene leads to missing neurons, which, in turn, affects the proper development
and successfully loaded them with the enzyme catalase, a potent antioxidant that counters the neuron-killing inflammation responsible for Parkinson's and other degenerative neurological disorders.
a thin layer at the back of the eye that contains millions of nerve cells. Among those are called cells rods and cones,
But those diseases leave most remaining neurons within the retina relatively intact, and various technologies under development aim to restore vision by targeting the surviving cells.
and can differentiate into neurons--constitute an interesting model to identify the genes and proteins whose expression is deregulated in patients with ASD.
In these different organisms, under-expression of the enzyme induced hypersensitivity to oxidative stress (i e. to the toxicity of free radicals), a smaller number of synapses and abnormal neurotransmission due to a reduction in the number of vesicles carrying neurotransmitters.
#Super-small needle technology for the brain However, one challenge is reducing the tissue/neuron damage associated with needle penetration, particularly for chronic insert experiment and future medical applications.
which allowed them to systematically test the response of individual neurons in the ant antennae to hydrocarbons found in the cuticles of worker ants and their queens.
After all, their incredible talent for olfactory discrimination depends not only on sensitively attuned neurons and an impressive collection of odorant receptors--ants have the largest odorant receptor gene family known in insects,
and controlling whether nerve cells are excited or inhibited (calm). Under normal conditions the system is balanced. But when we are aroused hyper and vigilant, glutamate surges.
Using this method to image neurons they showed that actin, a key component of the cytoskeleton (backbone of the cell), has a different structure in axons than in dendrites, two parts of a neuron.
But current super-resolution microscopy techniques do not deliver spectral information, which is useful for scientists to understand the behavior of individual molecules,
Alzheimer's, for example, may be related to degradation of the cytoskeleton inside neurons.""The cytoskeleton system is comprised of a host of interacting subcellular structures and proteins,
or"fusing,"little packets of neurotransmitters to the outer edges of neurons, where they are released
and then dock with chemical receptors in another neuron to trigger a response. Arrayin this latest research, the scientists found that when the SNARES and synaptotagmin-1 join up
triggering a gunshot-like release of neurotransmitters from one neuron to another. They also learned that the proteins join together before they arrive at a neuron's membrane,
which helps to explain how they trigger brain signaling so rapidly.""The neuron is not building the'gun'as it sits there on the membrane--it's already there,
"Brunger said. The team speculates that several of the joined protein complexes may group together
Beta-amyloid is known to make nerve cells hyperactive, and now it turns out that the eta-amyloid antagonizes this effect."
and protect neurons. Another example of Scales's practical application came from examining the 3d positions of active microglial cells and amyloid beta plaques.
or assays, were not available to measure ATP (the energy unit of the cell that is generated by mitochondria) in individual neurons.
the researchers tested energy levels in neurons using the new assays. They found that the genetic mutation associated with Leigh's disease compromised ATP levels,
which would be toxic to neurons, "says first author Divya Pathak, Phd, a postdoctoral fellow in the Gladstone Institute of Neurological disease."
"Applying their new assay in healthy neurons, the researchers also determined the energy threshold needed to support synaptic vesicle cycling--the process by
which brain cells release neurotransmitters to communicate with each other. The scientists blocked glycolysis, another way that cells make ATP,
and both types of boutons had sufficient ATP to support synaptic vesicle cycling. From this, the scientists concluded that under normal conditions,
has identified a protein that regulates the growth of neurons by transporting key metabolic enzymes to the tips of neural cells.
and choline acetyltransferase (Chat) find their way to the right region of the neuron is largely unknown.
and the University of Michigan (U-M). They identified and characterised a protein that transports the enzyme ACL to the tips of neurons,
-H in cell lines, primary neuron cultures and zebrafish using molecular genetics, protein biochemistry and high speed imaging.
marking ACL for transport by the enzyme kinesin-1 to the neuron terminals. Once there
The BNIP-H-induced increase of acetylcholine in turn launches a positive feedback loop involving the MAPK/ERK signalling pathway that ultimately promotes growth of neurites,
which are projections from neurons.""BNIP-H defines the precise localisation, duration and strength of acetylcholine signalling that determines the growth of neurons
and the coordination of body movements,"explained Assoc Prof Low, the corresponding author of the paper.
has identified a protein that regulates the growth of neurons by transporting key metabolic enzymes to the tips of neural cells.
and choline acetyltransferase (Chat) find their way to the right region of the neuron is largely unknown.
and the University of Michigan (U-M). They identified and characterised a protein that transports the enzyme ACL to the tips of neurons,
-H in cell lines, primary neuron cultures and zebrafish using molecular genetics, protein biochemistry and high speed imaging.
marking ACL for transport by the enzyme kinesin-1 to the neuron terminals. Once there
The BNIP-H-induced increase of acetylcholine in turn launches a positive feedback loop involving the MAPK/ERK signalling pathway that ultimately promotes growth of neurites,
which are projections from neurons.""BNIP-H defines the precise localisation, duration and strength of acetylcholine signalling that determines the growth of neurons
and the coordination of body movements,"explained Assoc Prof Low, the corresponding author of the paper.
Both cardiac cells in the heart and neurons in the brain communicate by electrical signals,
which stops nerve cells from working. A gene called HIFALPHA was found to regulate the nerve signals from damaged mitochondria and,
the early failure of nerve cells caused by mitochondrial damage was prevented. An identical effect was observed in flies with Leigh syndrome,
'The biggest surprise from our work is damaged that mitochondria produce a signal that actively prevents nerve cells from working properly.
Thanks to this study we now have a much better understanding of how nerve cells function,
potentially allowing them to observe communication between neurons, activation of immune cells, or stem cell differentiation, among other phenomena.
#Artificial skin Sends Touching Signals to Nerve cells Prosthetic limbs can restore an amputee ability to walk
and transmits signals via nerve cells, much as human skin does. Zhenan Bao and coworkers made the artificial skin by connecting three components:
and nerve cells containing light-activated ion channels. The pressure sensors are made of a carbon nanotube-elastomer composite shaped into tiny pyramidal structures that are coated onto a surface.
In their proof-of-concept study, they sent light from the LED through an optical fiber to stimulate neurons in mouse brain slices.
The nerve cells in these samples were decorated with engineered channelrhodopsins that open in response to light,
triggering nerve cells to fire. The work represents n important advance in the development of skinlike materials that mimic the functionality of human skin at an unprecedented level
and to stimulate specific groups of neurons. Although the ultimate goal is to treat traumatic brain injury
or neurons, can be formed by stimulating the front part of the brain which is involved in memory retention using minute amounts of electricity.
In the Neuron paper Courchesne, first author Michael V. Lombardo, Phd, a senior researcher at the University of Cambridge and assistant professor at the University of Cyprus, Pierce and colleagues describe the first effort to create a process capable
and cell signaling, for instance, between nerve cells in the brain and spinal cord. o our knowledge, this is the first transport protein designed from scratch that is,
#Fruit fly studies shed light on adaptability of nerve cells An international team of researchers at German Center for Neurodegenerative Diseases (DZNE)
and Tokyo Institute of technology (Tokyo Tech) have revealed in a collaborative study published today in NEURON, that neurons in the eye change on the molecular level
when they are exposed to prolonged light. The researchers could identify that a feedback signalling mechanism is responsible for these changes.
The innate neuronal property might be utilized to protect neurons from degeneration or cell death in the future.
Changes in the functional connections between neurons ynapsescontribute to our ability to adapt to environmental changes.
and the European Neuroscience Institute in Germany reveal details of the mechanisms behind synaptic plasticity. he synaptic changes that we have identified might reflect an innate neuronal property that leads to protection from excessive stimuli,
we might be able to protect neurons from degeneration or cell death. Recent studies have suggested that changes in a region at the presynaptic membrane
described as the active zone, control synapse function. The research teams based in Germany and Japan exposed living fruit flies the commonly studied Drosophila to different light regimes and then compared the active zones in the photoreceptors.
T-shaped structures at the presynaptic membrane tether synaptic vesicles and control the release of neurotransmitters to the postsynaptic neuron.
Future work may investigate how modifying the Wnt signal can be used to manipulate synaptic plasticity, with possible therapeutic applications for neurodegenerative or mental diseases n
the nerve cells in a specific area of the brain are activated suddenly in an excessive manner.
the researchers reproduced the hyperexcitability of epileptic neurons in mouse brains in vitro. They then injected GABA,
and that inhibits neurons, into this hyperactive region using the micropump. The scientists then observed that the compound not only stopped this abnormal activity in the target region,
Neurons in the brain are connected through junctions termed synapses and function by transmitting electrical activity (i e.,
a thin layer of cells within an embryo that contains genetic instructions to build hundreds of cell types, from neurons to adrenal cells.
Using this method to image neurons, they showed that actin, a key component of the cytoskeleton (backbone of the cell), has a different structure in axons than in dendrites, two parts of a neuron.
But current super-resolution microscopy techniques do not deliver spectral information, which is useful for scientists to understand the behavior of individual molecules,
Alzheimer, for example, may be related to degradation of the cytoskeleton inside neurons. he cytoskeleton system is comprised of a host of interacting subcellular structures and proteins,
Diffusion MRI measures the movement of water molecules to create a visual representation of the brain axons.
#Closing the loop with optogenetics Optogenetics provides a powerful tool for studying the brain by allowing researchers to activate neurons using simple light-based signals.
and in the neurons of animal models. he same stimulus pattern can produce highly variable levels of activity,
said Newman. his is potentially a very big deal in terms of developing therapies for aberrant forms of synaptic plasticity.
King College London, have discovered a new molecular witchthat controls the properties of neurons in response to changes in the activity of their neural network. The findings,
with logic boards and microprocessors representing neural circuits and neurons, respectively. While this analogy has served neuroscience well in the past,
have shed light on this problem by discovering that some neurons in the cerebral cortex can adapt their properties in response to changes in network activity such as those observed during learning of a motor task.
The authors studied two apparently different classes of fast-spiking interneurons, only to discover that they were actually looking at the same piece of ardwarewhich had the ability to oscillate between two different ground states.
Fast-spiking interneurons are part of a general class of neurons whose primary role is regulating the activity of the principal cells of the cerebral cortex, known as pyramidal cells.
language and memory. ur findings explain the underlying mechanisms behind the dynamic regulation of the identity of interneurons said Nathalie Dehorter of the MRC CDN
and protect neurons) instead. Scientists found a different application for Scales too. They examined the 3d positions of active microglial cells and amyloid beta plaques.
including neurons to potentially reconnect a severed spinal cord and repair paralysis. A variety of agents have been shown to induce transplanted stem cells to differentiate into neurons.
Tufts University biomedical engineers recently published the first report of a promising new way to induce human mesenchymal stem cells (or hmscs,
which are derived from bone marrow) to differentiate into neuron-like cells: treating them with exosomes. Exosomes are very small,
the Tufts researchers showed that exosomes from PC12 cells (neuron-like progenitor cells derived from rats) at various stages of their own differentiation could,
in turn, cause hmscs to become neuron-like cells. Exosomes had not previously been studied as a way to induce human stem cell differentiation.
thereby avoiding the need to use any kind of neural progenitor cell line to induce neuron growth,
In the brain, calcium is used to communicate information within and between neurons and it activates a host of other cell functions,
and its signaling pathway is critical for normal performance of neurons and that this signaling pathway represents a key ubin the pathogenesis of ASD,
specifically how it regulates the level of neuron excitability. The brains of people who have autism show signs of hyperexcitability,
The cell-sorting process can reduce cell viability and functions by 30 to 99 percent for many fragile or sensitive cells such as neurons, stem cells, liver cells and sperm cells.
and cell identityhat enables cells with the same genetic material to become, for example, a nerve cell, a muscle cell or a skin cell.
Both cardiac cells in the heart and neurons in the brain communicate by electrical signals,
MS is a condition of the central nervous system in which myelin, the coating around nerves, is damaged causing vision problems, stiffness, spasms and other symptoms.
aims to use electronics in a way that mimics the way neurons process information in organic brains.
At any given moment, the properties of a memristor just like those of a single neuron depend on
Eana Park/Stony Brook Universityboth cardiac cells in the heart and neurons in the brain communicate by electrical signals,
during which the nerve cells get out of their usual rhythm and fire in a very rapid frequency.
these channels act like a doorman to regulate the entry of calcium ions in the nerve cells. t has also been known for a long time that following transient severe brain injury and prior to an initial spontaneous epileptic seizure, the concentration of free zinc ions
This leads to a large increase in the amount of a special calcium ion channel in the nerve cells and overall, this significantly boosts the risk of epileptic seizures.
#Stimulating Neurons with Sound Over the past five years, optogenetics method for stimulating genetically engineered neurons with lightas taken the life sciences by storm.
Now researchers also have the option of engineering subsets of neurons and activating them with ultrasound,
a neuroscientist at Arizona State university who led the first group to directly stimulate neurons with ultrasound in 2008. t shows the mechanical sensitivity of ion channels
The worms ordinarily use these neuron-embedded TRP-4 channels to sense when their bodies are stretching.
The team hoped to engineer small groups of worm neurons to express TRP-4 channels
while allowing non-engineered neurons to remain unperturbed. But the researchers found that their low-frequency waves caused such small mechanical deformations that worms could not detect them.
and activate neurons. The researchers added TRP-4 channels to neurons known to make worms reverse directions
and were able to influence the worm movements by stimulating those neurons with ultrasound. They next decided to try out sonogenetics in a set of poorly understood worm cells called PVD neurons.
The researchers found that stimulating these neurons reduced the likelihood that the animals would change directions.
Finally, the researchers tested whether they could use sonogenetics on neurons 25 microns beneath the wormscuticles.
They used calcium imaging to show that the engineered neurons lit up when stimulated with sound.
The team is now working on adapting its technique for use in mice. Chalasani noted it may not even be necessary to use microbubbles to amplify the sound waves. e expect that perhaps
because the mammalian brain is bigger, the deformation might be sufficient to cause the neuron to detect it,
he said. Or, if the researchers do end up needing to use microbubbles, they may inject them into the mouse bloodstream.
In this case, each neuron should be within 20 microns of microbubbles-filled capillaries. The researchers would like to see sonogenetics used on humans down the line, perhaps as a less invasive form of deep-brain stimulation.
the amplified ultrasound waves also do appear to affect some other neurons. t not he same thing at this point as optogenetics, where it really an all-or-none thing,
#Artificial skin Communicates with Neurons Researchers have developed a new type of artificial skin that could pave the way for responsive prosthetics.
When the researchers measured the responses of individual neurons within the brain slice they found that it correlated perfectly with the pulses produced by the artificial skinlike materialp to 200 beats per second.
the system reportedly has the potential to aid sick or disabled people. eople with amyotrophic lateral sclerosis (ALS) motor neuron disease,
This process is crucial for neurons (nerve cells) to function properly. Compartments within a cell are much like different parts of a car explains Vasanth Ramamurthy Phd first author of the study.
A good example of compartmentalization is observed in a specialized type of light-sensing neurons found in the retina the photoreceptors which are made up of different compartments containing specific proteins essential for vision.
#Scientists create new protein-based material with some nerve Scientists at the University of California Berkeley have taken proteins from nerve cells
To create the biological equivalent of a polymer brush the researchers turned to neurofilaments pipe cleaner-shaped proteins found in nerve cells.
By acting as tiny cylindrical polymer brushes neurofilaments collectively assemble into a structural network that helps keep one end of the nerve cell propped open
#Scientists sniff out unexpected role for stem cells in the brain For decades scientists thought that neurons in the brain were born only during the early development period
and turn into new neurons in specific brain regions. The function of these neuroprogenitor cells remains an intense area of research.
Neurons in the olfactory bulb sort that information and relay the signals to the rest of the brain at which point we become aware of the smells we are experiencing.
In a process known as neurogenesis adult-born neuroprogenitor cells are generated in the subventricular zone deep in the brain
Dr. Belluscio who studies the olfactory system teamed up with Heather Cameron Ph d. a neurogenesis researcher at the NIH's National institute of mental health to better understand how the continuous addition of new neurons influences the circuit organization of the olfactory bulb.
and eliminate the stem cells that give rise to these new neurons in adults while leaving other olfactory bulb cells intact.
if new neurons are prevented from forming and entering the olfactory bulb the circuits remain in disarray.
We found that without the introduction of the new neurons the system could not recover from its disrupted state said Dr. Belluscio.
To further explore this idea his team also eliminated the formation of adult-born neurons in mice that did not experience sensory deprivation.
and that introducing new neurons alters the existing circuitry causing it to reorganize. However in this case the circuitry appears to be inherently unstable requiring a constant supply of new neurons
not only to recover its organization following disruption but also to maintain or stabilize its mature structure.
Dr. Belluscio and his colleagues speculate that new neurons in the olfactory bulb may be important to maintain
It's very exciting to find that new neurons affect the precise connections between neurons in the olfactory bulb.
Because new neurons throughout the brain share many features it seems likely that neurogenesis in other regions such as the hippocampus
The current study suggests that the protein is transferred during nerve cell communication. It is at this point of interaction that the researchers want to intervene
and pile up forming chains of lithium metal called dendrites Cui explained. The dendrites can penetrate the porous separator
and eventually make contact with the cathode causing the battery to short. Smart separatorin the last couple of years we've been thinking about building a smart separator that can detect shorting before the dendrites reach the cathode said Cui a member of the photon science faculty at the SLAC National Accelerator Laboratory
at Stanford. To address the problem Cui and his colleagues applied a nanolayer of copper onto one side of a polymer separator creating a novel third electrode halfway between the anode and the cathode.
When the dendrites grow long enough to reach the copper coating the voltage drops to zero.
That lets you know that the dendrites have grown halfway across the battery. It's a warning that the battery should be removed before the dendrites reach the cathode and cause a short circuit.
The build up of dendrites is most likely to occur during charging not during the discharge phase
when the battery is being used. You might get a message on your phone telling you that the voltage has dropped to zero so the battery needs to be replaced Zhuo said.
Locating defectsin addition to observing a drop in voltage co-lead author Hui Wu was able to pinpoint where the dendrites had punctured the copper conductor simply by measuring the electrical resistance between the separator and the cathode.
He confirmed the location of the tiny puncture holes by actually watching the dendrites grow under a microscope.
and colleagues have shown that a lentivirus encoding let-7 injected into mouse neurons promotes the autophagic turnover of toxic misfolded proteins associated with neurodegenerative disease. e also demonstrate that treatment with anti-let-7 can block autophagy
#How rabies hijacks neurons to attack brain Rabies causes acute inflammation of the brain, producing psychosis and violent aggression.
"We have shown that rabies enters a neuron in the peripheral nervous system by binding to a nerve growth factor receptor, responsible for the health of neurons, called p75.
The difference is that its transport is very fast, even faster than that of its endogenous ligand, the small molecules that travel regularly along the neuron and keep the neuron healthy."
The researchers"saw"the virus hijack the"train"transporting cell components along a neuron and drove it straight into the spinal cord.
Nerve cells, or neurons outside the central nervous system are highly asymmetric. A long protrusion called an axon extends from the cell body to another nerve cell or organ along a specific transmission route.
In addition to rapid transmission of electric impulses, axons also transport molecular materials over these distances.""Axonal transport is a delicate and crucial process for neuronal survival,
and when disrupted it can lead to neurodegenerative diseases, "said Dr. Perlson.""Understanding how an organism such as rabies manipulates this machinery may help us in the future to either restore the process
By shedding light on how the virus hijacks the transport system in nerve cells to reach its target organ with maximal speed and efficiency,
Disruptions of the neuron train system also contribute to neurodegenerative diseases, like Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS.
According to Dr. Perlson,"An improved understanding of how the neuron train works could lead to new treatments for these disorders as well
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