What gives us fingertip dexterity?

In a novel experiment, a USC biomedical engineer examines the intricate circuitry between hand manipulation skills and specialized neural circuits in the brain

Quickly moving your fingertips to tap or press a surface is essential for everyday life to, say, pick up small objects, use a BlackBerry or an iPhone. But researchers at the University of Southern California say that this seemingly trivial action is the result of a complex neuro-motor-mechanical process orchestrated with precision timing by the brain, nervous system and muscles of the hand

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Scientists restore walking after spinal cord injury

Spinal cord damage blocks the routes that the brain uses to send messages to the nerve cells that control walking. Until now, doctors believed that the only way for injured patients to walk again was to re-grow the long nerve highways that link the brain and base of the spinal cord. For the first time, a UCLA study shows that the central nervous system can reorganize itself and follow new pathways to restore the cellular communication required for movement.

Researchers take first steps towards spinal cord reconstruction following injury

A new study has identified what may be a pivotal first step towards the regeneration of nerve cells following spinal cord injury, using the body’s own stem cells.

This seminal study, published in this week’s Proceedings of the National Academy of Science, identifies key elements in the body’s reaction to spinal injury, critical information that could lead to novel therapies for repairing previously irreversible nerve damage in the injured spinal cord.

Blood clotting protein may inhibit spinal cord regeneration

Fibrinogen, a blood-clotting protein found in circulating blood, has been found to inhibit the growth of central nervous system neuronal cells, a process that is necessary for the regeneration of the spinal cord after traumatic injury. The findings by researchers at the University of California, San Diego (UCSD) School of Medicine, may explain why the human body is unable to repair itself after most spinal cord injuries.

Nanomedicine opens the way for nerve cell regeneration

The ability to regenerate nerve cells in the body could reduce the effects of trauma and disease in a dramatic way. In two presentations at the NSTI Nanotech 2007 Conference, researchers describe the use of nanotechnology to enhance the regeneration of nerve cells. In the first method, developed at the University of Miami, researchers show how magnetic nanoparticles (MNPs) may be used to create mechanical tension that stimulates the growth and elongation of axons of the central nervous system neurons. The second method from the University of California, Berkeley uses aligned nanofibers containing one or more growth factors to provide a bioactive matrix where nerve cells can regrow.

Robotic exoskeleton replaces muscle work

A robotic exoskeleton controlled by the wearer’s own nervous system could help users regain limb function, which is encouraging news for people with partial nervous system impairment, say University of Michigan researchers.

The ankle exoskeleton developed at U-M was worn by healthy subjects to measure how the device affected ankle function. The U-M team has no plans to build a commercial exoskeleton, but their results suggest promising applications for rehabilitation and physical therapy, and a similar approach could be used by other groups who do build such technology.

Conceptualizing a cyborg

Investigators at the University of Pennsylvania School of Medicine describe the basis for developing a biological interface that could link a patient’s nervous system to a thought-driven artificial limb. Their conceptual framework – which brings together years of spinal-cord injury research – is published in the January issue of Neurosurgery.

Diabetes breakthrough

In a discovery that has stunned even those behind it, scientists at a Toronto hospital say they have proof the body’s nervous system helps trigger diabetes, opening the door to a potential near-cure of the disease that affects millions.

Diabetic mice became healthy virtually overnight after researchers injected a substance to counteract the effect of malfunctioning pain neurons in the pancreas.

Major breakthrough in the mechanism of myelin formation

The discovery reported in this study sheds light on the mechanisms that control how myelin is formed during development of the nerves. The article, which will be published in the November 3rd issue of Science, constitutes an important step forward in our understanding of the process of myelination, and opens the way to new research in this field. The results of their study that could have a major impact on the treatment of diseases such as multiple sclerosis, and peripheral neuropathies.

Elevated testosterone kills nerve cells

-A Yale School of Medicine study shows for the first time that a high level of testosterone, such as that caused by the use of steroids to increase muscle mass or for replacement therapy, can lead to a catastrophic loss of brain cells.

Taking large doses of androgens, or steroids, is known to cause hyperexcitability, a highly aggressive nature, and suicidal tendencies. These behavioral changes could be evidence of alterations in neuronal function caused by the steroids, said the senior author, Barbara Ehrlich, professor of pharmacology and physiology.

Caffeine reduces the risk of Alzheimer’s disease

If you think that your daily cups of coffee only provide you with alertness after you wake up or during the day, think again. Long-term intake of caffeine, the major constituent in coffee and tea, has been shown to reduce the risk of Alzheimer’s in mice that develop the disease.

In a study just published on-line in the Journal Neuroscience, researchers at the Byrd Alzheimer’s Institute in Tampa, Florida, are reporting that caffeine intake equivalent to five cups of coffee a day in humans, protects Alzheimer’s mice against otherwise certain memory impairment and reduces Alzheimer’s pathology in their brains.

Natural vitamin E tocotrienol reaches blood at protective levels

Two recent studies offer new evidence suggesting an alternative form of natural vitamin E can be taken by mouth and will reach the blood in humans at levels determined to protect against stroke and other diseases.
Vitamin E occurs naturally in eight different forms. The primary vitamin E on drugstore shelves is called tocopherol, or TCP. But another natural form of vitamin E surfacing as a potent neuroprotective agent in repeated Ohio State University Medical Center studies is tocotrienol, or TCT.

Long-term changes in experience cause neurons to sprout new long-lasting connections

Howard Hughes Medical Institute researchers have discovered that neurons in the brains of mice sprout robust new connections when the animals are adjusting to new experiences. The new connections alter the circuitry of the brain by changing communication between neurons.
The researchers said their findings aid understanding of how procedural learning induces long-term rewiring of the brain. This type of learning is used in mastering skills such as riding a bicycle or typing on a computer.

Neurons grown from embryonic stem cells restore function in paralyzed rats

For the first time, researchers have enticed transplants of embryonic stem cell-derived motor neurons in the spinal cord to connect with muscles and partially restore function in paralyzed animals. The study suggests that similar techniques may be useful for treating such disorders as spinal cord injury, transverse myelitis, amyotrophic lateral sclerosis (ALS), and spinal muscular atrophy. The study was funded in part by the NIH's National Institute of Neurological Disorders and Stroke (NINDS).

Where the brain organizes actions

Researchers have discovered that Broca's area in the brain–best known as the region that evolved to manage speech production–is a major "executive" center in the brain for organizing hierarchies of behaviors. Such planning ability, from cooking a meal to organizing a space mission, is considered one of the hallmarks of human intelligence.

The researchers found that Broca's area–which lies on the left side of the brain about in the temple region–and its counterpart on the right side activate when people are asked to organize plans of action. They said their finding of the general executive function of Broca's area could explain its key role in language production.

New roles for growth factors: Enticing nerve cells to muscles

During embryonic development, nerve cells hesitantly extend tentacle-like protrusions called axons that sniff their way through a labyrinth of attractive and repulsive chemical cues that guide them to their target.

While several recent studies discovered molecules that repel motor neuron axons from incorrect targets in the limb, scientists at the Salk Institute for Biological Studies have identified a molecule, known as FGF, that actively lures growing axons closer to the right destination. Their findings appear in the June 15 issue of Neuron.

Cure found for Huntington disease in mice offers hope for treatment in humans

Researchers at the University of British Columbia's Centre for Molecular Medicine and Therapeutics (CMMT) have provided ground-breaking evidence for a cure for Huntington disease in a mouse offering hope that this disease can be relieved in humans.

Published today in Cell journal, Dr. Michael Hayden and colleagues discovered that by preventing the cleavage of the mutant huntingtin protein responsible for Huntington disease (HD) in a mouse model, the degenerative symptoms underlying the illness do not appear and the mouse displays normal brain function. This is the first time that a cure for HD in mice has been successfully achieved.

New stem-cell findings can help the body to cure itself

Researchers at Karolinska Institutet have identified an important mechanism that regulates how many new cells are produced by each intestinal stem cell. The study is published in the latest issue of the prestigious scientific journal, Cell. "This might eventually help us develop new drugs for things like neurological disorders and anaemia," says Professor Jonas Frisén.

Researchers discover botulism toxin’s insidious route into nerve cells

Botulinum neurotoxin A can be either the greatest wrinkle remover or one of the world’s most potent biological weapons. To perform either job, however, the toxin must first find a way to enter cells.

But understanding how the toxin — one of seven neurotoxins produced by the bacterium Clostridium botulinum — enters nerve cells has proved elusive for scientists. Despite a decade-long search for the receptor by labs around the world, researchers had come up empty handed.

Now, a research team led by Howard Hughes Medical Institute (HHMI) researcher Edwin R. Chapman reports that it has identified the cellular receptor for botulinum neurotoxin A. The group’s work was published in the March 16, 2006, edition of ScienceXpress, which provides electronic publication of selected Science papers in advance of print. The finding offers important new insights that suggest how the toxin shuts down nerve cells with deadly efficiency.

Potassium channel mutations implicated in neurodegeneration and mental retardation

For the first time, researchers have linked mutations in a gene that regulates how potassium enters cells to a neurodegenerative disease and to another disorder that causes mental retardation and coordination problems. The findings may lead to new ways of treating a broad range of disorders, including Alzheimer’s and Parkinson’s diseases.

Role of the nervous system in targeting stem cells in their niches is discovered

A group, led by Dr. Paul Frenette at Mount Sinai School of Medicine, found that the sympathetic–or “fight or flight” branch–of the nervous system plays a critical role in coaxing bone marrow stem cells into the bloodstream. Bone marrow cells known as hematopoietic stem cells are the source for blood and immune cells.

New study by Mount Sinai researchers may lead to improved stem cell therapies for patients with compromised immune systems due to intensive cancer therapy or autoimmune disease.

Discoveries may advance stem cell therapy for Parkinson’s, cancer patients

Two studies in the Jan. 27, 2006 issue of Cell have yielded evidence that could prove a boon for stem cell therapies aimed at patients with Parkinson’s disease and those with compromised immune systems due to intensive cancer therapy or autoimmune disease, according to researchers. The basic findings in mice revealed critical factors that determine the fate of one type of nerve cell progenitor and that set bone marrow stem cells into action.

Researchers at the Karolinska Institutet in Sweden discovered a “master determinant” that turns embryonic stem cells into bona fide dopamine neurons, brain cells that degenerate in those with Parkinson’s disease. The findings hold promise for the future of cell replacement therapy for the debilitating and incurable disease characterized by tremors, said study authors Thomas Perlmann and Johan Ericson. The results also underscore the general importance of a thorough understanding of development for producing authentic cells of a desired type from stem cells.

Tiny RNA molecules fine-tune the brain’s synapses

Non-coding regions of the genome – those that don’t code for proteins – are now known to include important elements that regulate gene activity. Among those elements are microRNAs, tiny, recently discovered RNA molecules that suppress gene expression. Increasing evidence indicates a role for microRNAs in the developing nervous system, and researchers from Children’s Hospital Boston now demonstrate that one microRNA affects the development of synapses – the points of communication between brain cells that underlie learning and memory.

Immune system cells may help to maintain cognition and brain cell renewal

A team of scientists at the Weizmann Institute of Science, has come up with new findings that may have implications in delaying and slowing down cognitive deterioration in old age. The basis for these developments is, published today in the February issue of Nature Neuroscience, that immune cells contribute to maintaining the brain’s ability to maintain cognitive ability and cell renewal throughout life.

Scientists discover a protein linked to serotonin and depression

For the more than 18 million Americans who suffer from depressive illnesses, the best pharmacological treatments are those that increase levels of serotonin, the brain chemical that regulates mood, sleep and memory. New research by an international team of scientists, led by Rockefeller University researchers in Nobel prize winner Paul Greengard’s laboratory, shows that a gene called p11 is closely related to serotonin transmission in the brain — and may play a key role in determining a person’s susceptibility to depression.

The newly discovered link between depression and the serotonin system, reported in the January 6 issue of the journal Science, could lead to new treatments for these mental disorders.

Researcher finds neuron growth in adult brain

Despite the prevailing belief that adult brain cells don’t grow, a researcher at MIT’s Picower Institute for Learning and Memory reports in the Dec. 27 issue of Public Library of Science (PLoS) Biology that structural remodeling of neurons does in fact occur in mature brains.

This finding means that it may one day be possible to grow new cells to replace ones damaged by disease or spinal cord injury, such as the one that paralyzed the late actor Christopher Reeve.

Bionic fiction becomes science fact

A highly dexterous, bio-inspired artificial hand and sensory system that could provide patients with active feeling, is being developed by a European project.

The CYBERHAND project aims to hard wire this hand into the nervous system, allowing sensory feedback from the hand to reach the brain, and instructions to come from the brain to control the hand, at least in part.

Nerve regeneration is possible in spinal cord injuries

A team of scientists at UCSF has made a critical discovery that may help in the development of techniques to promote functional recovery after a spinal cord injury. By stimulating nerve cells in laboratory rats at the time of the injury and then again one week later, the scientists were able to increase the growth capacity of nerve cells and to sustain that capacity. Both factors are critical for nerve regeneration.