Monday, December 14, 2009

New Hope for Brain, Spinal Cord Injuries

Deletion of key gene could help nerve fibers regenerate, researchers say


Deleting a gene that suppresses natural growth factors enables regeneration of injured nerve fibers (axons) in mice, a new study shows.

The finding may lead to new treatments for people with brain and spinal cord injuries.

Researchers at Children's Hospital Boston deleted the gene SOCS3 -- an inhibitor of a growth pathway called mTOR -- in the retinal ganglion cells of mice. These cells are in the optic nerve, which carries signals from the eyes to the brain.

Removel of SOCS3 resulted in vigorous growth of injured axons. The greatest improvement was seen after one week, when the researchers also detected signs that the mTOR pathway was re-activated. Axon growth increased even more when the researchers applied a growth factor called ciliary neurotrophic factor (CNTF) directly to the eye of mice in which SOCS3 had been deleted. But CNTF only modestly boosted axon growth in mice that still had SOCS3.

"CNTF and other cytokines [cellular signaling molecules] have been tested for promoting axon regeneration previously, but with no success," study leader Zhigang He, of the F.M. Kirby Neurobiology Center at Children's Hospital Boston, said in a university news release. "Now we know that this is due to the tight negative control of SOCS3. Inhibiting SOCS3, using small molecule compounds or RNA interference, might allow these cytokine growth factors to be functional."

The study appears in the Dec. 10 issue of Neuron.

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Monday, September 21, 2009

Scientists Make Paralyzed Rats Walk Again After Spinal Cord Injury

UCLA researchers have discovered that a combination of drugs, electrical stimulation and regular exercise can enable paralyzed rats to walk and even run again while supporting their full weight on a treadmill.

Published Nov. 20 in the online edition of Nature Neuroscience, the findings suggest that the regeneration of severed nerve fibers is not required for paraplegic rats to learn to walk again. The finding may hold implications for human rehabilitation after spinal cord injuries.

"The spinal cord contains nerve circuits that can generate rhythmic activity without input from the brain to drive the hind leg muscles in a way that resembles walking called 'stepping,'" explained principal investigator Reggie Edgerton, a professor of neurobiology and physiological sciences at the David Geffen School of Medicine at UCLA.

"Previous studies have tried to tap into this circuitry to help victims of spinal cord injury," he added. "While other researchers have elicited similar leg movements in people with complete spinal injuries, they have not achieved full weight-bearing and sustained stepping as we have in our study."

Edgerton's team tested rats with complete spinal injuries that left no voluntary movement in their hind legs. After setting the paralyzed rats on a moving treadmill belt, the scientists administered drugs that act on the neurotransmitter serotonin and applied low levels of electrical currents to the spinal cord below the point of injury.

The combination of stimulation and sensation derived from the rats' limbs moving on a treadmill belt triggered the spinal rhythm-generating circuitry and prompted walking motion in the rats' paralyzed hind legs.

Daily treadmill training over several weeks eventually enabled the rats to regain full weight-bearing walking, including backwards, sideways and at running speed. However, the injury still interrupted the brain's connection to the spinal cord-based rhythmic walking circuitry, leaving the rats unable to walk of their own accord.

Neuro-prosthetic devices may bridge human spinal cord injuries to some extent, however, so activating the spinal cord rhythmic circuitry as the UCLA team did may help in rehabilitation after spinal cord injuries.

The study was funded by the Christopher and Dana Reeve Foundation, Craig Nielsen Foundation, National Institute of Neurological Disorders and Stroke, U.S. Civilian Research and Development Foundation, International Paraplegic Foundation, Swiss National Science Foundation and the Russian Foundation for Basic Research Grants.

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Tuesday, July 28, 2009

Stem-Cell Breakthrough

It's a chilling thought. In the coming year, 130,000 people worldwide will suffer spinal-cord injuries?in a car crash, perhaps, or a fall. More than 90 percent of them will endure at least partial paralysis. There is no cure. But after a decade of hype and controversy over research on embryonic stem cells?cells that could, among other things, potentially repair injured spinal cords?the world's first clinical trial is about to begin. As early as this month, the first of 10 newly injured Americans, paralyzed from the waist down, will become participants in a study to assess the safety of a conservative, low-dose treatment. If all goes well, researchers will have taken a promising step toward a goal that once would have been considered a miracle?to help the lame walk.

The trial signals a new energy permeating the field of stem-cell research. More than 3,000 scientists recently met in Barcelona for the annual conference of the International Society for Stem Cell Research, compared with just 600 researchers five years ago. Money from major pharmaceutical companies is following the advances. Former U.S. vice president Al Gore, now a partner in the venture-capital firm Kleiner Perkins Caufield & Byers, has thrown his weight behind the research. In April, the firm joined with Highland Capital Partners to invest $20 million in iZumi Bio (now iPierian), a startup firm working on stem-cell therapies.
Click here to find out more!

Despite the considerable hype surrounding stem cells in recent years, the possibilities now appear to be broader than most people realize. In addition to helping replace damaged cells in patients with diseases like diabetes or Parkinson's, stem cells have the potential to change how we develop drugs and unravel the biology of disease. They may even be used one day to create replacement organs. "There's been a massive injection of optimism into the field," says stem-cell biologist Alan Trounson, president of the California Institute for Regenerative Medicine. "It's remarkable how fast it's progressing."

Much of the excitement comes from the development of a new type of stem cells, called "induced pluripotent" stem cells, or iPS. Shinya Yamanaka first concocted the cells in his Kyoto University lab by inserting four genes into fully formed adult skin cells. They began to behave like embryonic stem cells, capable of forming unlimited copies of any of the body's 220 cell types. Because iPS cells can be derived from a patient's own adult cells, they do not carry the risk of rejection by the immune system. Equally important, because iPS cells are not derived from embryos, they skirt a major ethical and religious problem.

The first iPS cells, however, will not be used as replacement tissue for spinal cords and other organs. Because iPS cells have subtle (and potentially dangerous) differences from true embryonic stem cells, many doctors are leery of putting them directly into patients until more research is done. But the cells could be immensely important in helping scientists understand and treat genetically based diseases.

By the time a full-blown disease has emerged, says Harvard stem-cell biologist Konrad Hochedlinger, it's like an airplane that has crashed. You can examine the wreckage for clues, but what you really want is the plane's black boxes?the flight-data and cockpit voice recorders that tell you exactly how electrical systems failed, hardware malfunctioned, and pilots made crucial errors. That's what doctors think iPS cells could provide. By coaxing some iPS cells into becoming the cell types affected in Huntington's disease, type 1 diabetes, or ALS (Lou Gehrig's disease), scientists will be able to watch in the lab as the disease unfolds. They'll be able to understand how the disease starts, which could lead to new ways of blocking it.

Embryonic stem cells are still regarded as the gold standard. That's why there is intense interest in the U.S. spinal-cord-injury trial. Sponsored by Geron Corp. in California, the trial will recruit patients within one to two weeks of their injuries, before scar tissue has formed. Doctors will inject a derivative of stem cells, called progenitor cells, that manufacture myelin, the substance that coats the long, spindly projections on nerve cells, much the same way that insulation coats electrical wires. Damage to cells that make and maintain the myelin sheath, as happens in spinal-cord injuries, prevents nerves from conveying messages from the brain. Although it's not clear yet whether the treatment is effective or safe, the restoration of even partial function would be a huge advance.

Geron's CEO, Dr. Thomas Okarma, thinks that spinal injury is a logical place to begin. Because patients will be completely paralyzed from the waist down, any improvement will be the result of the therapy, not chance. And the spinal cord is an "immune-privileged site," meaning that the attack cells of the immune system cannot get in and destroy the embryo-derived cells. "If the therapy is safe and effective, the potential impact will extend way beyond spinal-cord injury," says Okarma. "It will mark the start of a new era in medical therapeutics."

Other companies aren't waiting for the results. The U.S. pharmaceutical giant Pfizer is pursuing two other embryonic-stem-cell-based therapies, which it hopes to have in clinical trials by 2011. In April the company partnered with University College London to pursue a therapy for macular degeneration, the principal cause of blindness in the elderly. The disease leads to the gradual destruction of the macula, the sensitive central portion of the retina. But Peter Coffey, professor of cellular therapy and visual sciences at UCL, is using embryonic cells to make the same type of support cells that lie just behind the retina, providing it with nutrients. The goal is to implant a disc-shaped layer of the cells behind the retina. Immune rejection should not be a problem, since the eye is also immune-privileged.

Pfizer's other collaboration, with Novocell in California, aims to devise a treatment for some of the 100 million patients worldwide with insulin-dependent diabetes. Novocell is using embryonic stem cells to help regenerate all five of the pancreas's cell types. But there's a hitch. Unlike the eye or the spinal cord, the pancreas has no immune protection. For this, Novocell has devised a clever solution. It encases the stem-cell-derived progenitor cells in a capsule that can be implanted in the body. The pore size of the fabric is large enough to allow oxygen, glucose, and insulin to pass through but small enough to keep out big immune cells. "If problems should develop, the surgeon can easily remove the capsule," says Liz Bui, director of intellectual property for Novocell.

Some researchers aren't interested in just replacing impaired cells. They're using adult stem cells?which exist within organs to help with minor repairs?to grow entire replacement organs and tissues. Dr. Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest University in North Carolina, has made human bladders in this way. He starts by taking a small bladder biopsy from the patient and extracting his or her stem cells. After allowing the cells to multiply in the lab for about a month, he spreads them onto a collagen scaffold fashioned in the shape of a bladder. He then incubates the would-be organ in a bioreactor that provides the same temperature, oxygen level, growth factors, and nutrients that would be found in the body. In two weeks, he has a small but functional organ, ready for a patient.

In the early 2000s, Atala completed the procedure on seven children with spina bifida, who never developed fully functional bladders. He has now followed these patients for eight years to make sure there are no drastic failures or side effects. And he has moved on to other possible replacement parts. "We're working on 22 tissues and organs, including kidneys, heart valves, and cartilage," he says.

Because any new therapy is inherently risky, researchers are careful about creating false hopes that cures are just around the corner. Therapies that succeed in the idealized world of the lab can fail in real life or take decades to put into practice. As doctors and regulators begin to consider treating patients, they still have basic questions. Will the cells survive for long in the body? Will they integrate to form functioning tissue? Will the benefits outweigh risks that may become apparent only decades from now? Scientists are daring to hope, though, that after a decade of hype, real progress is imminent. Millions of patients worldwide could one day be the beneficiaries.

By Anne Underwood | NEWSWEEK

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Tuesday, December 16, 2008

Help Find A Cure for SCI!

By joining Find A Cure Panel?s exciting online research panel for people with spinal cord injuries, you will be empowered to share your personal experiences in vital research.

What's more, for each survey you complete a $10 donation is made directly to a worthy nonprofit organization in spinal cord injury research and support.

Registering is fast, free and your privacy is completely protected!

Registration Link: Find A Cure Panel

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Sunday, December 14, 2008

Fat Cells May Restore Spinal Cord Function Post Injury

Mature fat cells helped mice recover from spinal cord injuries, according to a promising new study. They could become a source for cell replacement therapy to treat central nervous system disorders in humans.

Yuki Ohta of the St. Mariana University School of Medicine, Kawasaki, Japan, who led the study, said fat or adipose-derived stem cells have been shown to differentiate into neuronal cells in a test tube setting.

Now, for the first time fat cells have been shown to successfully differentiate into neuronal cells in in-vivo (animal models) tests. The fat cells are grown under culture conditions that result in their becoming de-differentiated fat (DFAT) cells, according to a St Mariana release.

"These cells, called DFAT cells, are plentiful and can be easily obtained from adipose tissue without discomfort and represent autologous (same patient) tissue," said Ohta.

Tests in animal models confirmed that the injected cells survived without the aid of immunosuppression drugs and that the DFAT-grafted animals showed significantly better motor function than controls, said Ohta and colleagues.

"We concluded that DFAT-derived neurotrophic factors contributed to promotion of functional recovery after spinal cord injury (SCI)," said Ohta.

"Transplanting DFAT cells into SCI rats significantly promoted the recovery of their hind limb function."

"These studies demonstrate the ability to obtain stem cells from a patient?s own fat that can help repair injury to the spinal cord," said Paul R. Sanberg, University of South Florida Health, and joint editor-in-chief of Cell Transplantation, which published the report.

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Friday, November 21, 2008

Nanotechnology for Spinal Cord Injury

A cure for spinal injuries that leave people paralyzed, currently incurable, is being developed by Researchers at Northwestern University in Chicago. They are looking into using new nanotechnology that could enable them to completely heal cut and severed spinal cords allowing the previously paralyzed to walk again.

Spinal cord injury often leads to permanent paralysis and loss of sensation below the site of the injury due to damaged nerve fibers which can?t regenerate. These nerve fibers (axons) have the capacity to grow but don?t because they are blocked by scar tissue that have developed around the injury. Northwestern University researchers have shown that a new nano-engineered gel inhibits the formation of scar tissue at the injury site and enables the severed spinal cord fibers to regenerate and grow.

The gel is injected as a liquid into the spinal cord and self -assembles into a scaffold that supports the new nerve fibers as they grow up and down the spinal cord, penetrating the site of the injury. When the gel was injected into mice with a spinal cord injury, after six weeks the animals had a greatly enhanced ability to use their hind legs and walk.

However it was stressed that the results were preliminary and there is no magic bullet and it may not necessarily work on humans, but it helps a new technology to develop treatments for spinal injuries.

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Nose Cells May Heal Spinal Cord Injuries

People paralysed by spinal cord injuries could soon be "repaired" using cells from their own noses, say Otago University researchers.


The Health Ministry's ethics committee has just approved an application by the Spinal Cord Society to open the way for a clinical trial involving 12 patients, which could start next year.

The society's president, Noela Vallis, said there was no shortage of volunteers ready to take part.

"Some have already gone overseas out of a sense of frustration that they can't access it [the experimental treatment] here," Mrs Vallis said.

About 5000 Kiwis are in wheelchairs as a result of accidents - the highest rate of any country in the developed world.

Research director Jim Faed, who heads the the Spinal Cord Society's lab at Otago University, has spent five years developing laboratory methods for growing cells potentially useful for spinal cord injury repair.

His team is focusing on two promising cell types: one is a kind of adult stem cell produced by a patient's own bone marrow.

However, researchers are likely to begin trials using olfactory (scent receptor) cells from the patient's nose, injecting them into damaged spinal cord.

"The olfactory tissue in the nose is unique because it is the only place in the body where there is constant replacement of nerve cells throughout life," Dr Faed said.

"There is growing medical opinion that these cells can help overcome the blocks that prevent nerve cells regenerating after damage to the spinal cord."

The nasal tissue acts like "nurse cells", providing growth factor hormone to nerve cells, enabling them to make "meaningful connections".

Internationally, several research groups have done animal trials using the cells, but there has been only one human trial - in Portugal in 2006. The Otago group is in contact with Portuguese neuropathologist Carlos Lima, who pioneered that trial.

Dr Faed said some participants experienced side-effects, but they were "few and manageable" and none had been fatal.

Positive benefits for patients included return of some muscle function and sensation in parts of the body which previously had no feeling.

Dr Faed said the Dunedin lab hoped to get full approval for the trial before Christmas, and would then begin recruiting patients. The first 12 could start treatment next year.

Mrs Vallis - who founded the society after her late husband was paralysed in an accident - said the group aimed to raise $1 million to fund the trial, in addition to the $300,000 it finds every year to run the lab. "We should be at the forefront of developing this medical treatment, given the number of our citizens in wheelchairs."

Feilding man Iain Scott, a quadriplegic since dislocating his neck while playing rugby 19 years ago, said the possibility of the treatment was "huge" and gave hope to people with spinal cord injuries. "If nothing happens, at least you had a go ... you don't want to die wondering."

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Promising Therapies for Spinal Cord Injuries

A quarter of a million Americans are currently living with spinal cord injuries, according to the National Institute of Neurological Disorders and Stroke.

Although most people know this type of injury can be a devastating diagnosis, not everyone knows there are many different types of spinal cord injuries. The location of the injury along the spinal cord determines what parts of the body are affected. Different types of spinal cord injuries include:
  • Cervical Spinal Cord Injury: Affects vertebrae C1-C8 and causes paralysis or weakness in both arms and legs. This is also known as quadriplegia or tetraplegia.
  • Thoracic Spinal Cord Injury: Affects vertebrae T1-T12. These injuries can cause paralysis or weakness of the legs along with loss of physical sensation, bowel, bladder and sexual function.
  • Lumbar Spinal Cord Injury: Affects vertebrae L1-L5 and result in weakness or paralysis of the legs. This is also known as paraplegia.
  • Sacral Spinal Cord Injury: Affects vertebrae S1-S5. Sacral level injuries mainly cause loss of bowel and bladder function as well as sexual dysfunction. They can also cause weakness of paralysis of the hips and legs.
Injuries can also be complete or incomplete. Complete injuries are indicated by a total lack of sensory and motor function below the level of injury, whereas incomplete injuries are marked by some remaining sensation and movement (Source: Paralysis Resource Center).

With spinal cord injuries, the speed and quality of medical attention can dictate how the patient will live the rest of his or her life. Immediate treatment can include medications, immobilization and surgery.

One of the most important drugs used to treat spinal cord injuries is methylprednisolone, an adrenal corticosteroid that protects against further damage if administered within eight hours of injury. However, this drug may pose a risk of harmful side effects.

Clinical trials of a compound called GM-1 ganglioside show it may be another drug that can protect against secondary damage in these types of injuries. The compound is also showing promise in improving recovery during rehabilitation, a process that all victims of spinal cord injury have to undergo -- sometimes for years.

Another promising therapy for spinal cord injury involves an electronic chip implanted in the brain. Studies in rats show the animals could move a prosthetic arm using only their thoughts.

Researchers from the University of Florida implanted an electronic chip into rats' brains. A computer decoded the chip, and over time, the computer learned to adapt to the rats' needs. When a rat thought about moving, the computer responded by moving a robotic arm.

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Sunday, July 20, 2008

Stem Cells Identified for Spinal-Cord Repair

A researcher at MIT?s Picower Institute for Learning and Memory has pinpointed stem cells within the spinal cord that, if persuaded to differentiate into more healing cells and fewer scarring cells following an injury, may lead to a new, non-surgical treatment for debilitating spinal-cord injuries.

The work, reported in the July issue of the journal PLoS (Public Library of Science) Biology, is by Konstantinos Meletis, a postdoctoral fellow at the Picower Institute, and colleagues at the Karolinska Institute in Sweden. Their results could lead to drugs that might restore some degree of mobility to the 30,000 people worldwide afflicted each year with spinal-cord injuries.

In a developing embryo, stem cells differentiate into all the specialized tissues of the body. In adults, stem cells act as a repair system, replenishing specialized cells, but also maintaining the normal turnover of regenerative organs such as blood, skin or intestinal tissues.

The tiny number of stem cells in the adult spinal cord proliferate slowly or rarely, and fail to promote regeneration on their own. But recent experiments show that these same cells, grown in the lab and returned to the injury site, can restore some function in paralyzed rodents and primates.

The researchers at MIT and the Karolinska Institute found that neural stem cells in the adult spinal cord are limited to a layer of cube- or column-shaped, cilia-covered cells called ependymal cells. These cells make up the thin membrane lining the inner-brain ventricles and the connecting central column of the spinal cord.

?We have been able to genetically mark this neural stem cell population and then follow their behavior,? Meletis said. ?We find that these cells proliferate upon spinal cord injury, migrate toward the injury site and differentiate over several months.?

The study uncovers the molecular mechanism underlying the tantalizing results of the rodent and primate and goes one step further: By identifying for the first time where this subpopulation of cells is found, they pave a path toward manipulating them with drugs to boost their inborn ability to repair damaged nerve cells.

?The ependymal cells? ability to turn into several different cell types upon injury makes them very interesting from an intervention aspect: Imagine if we could regulate the behavior of this stem cell population to repair damaged nerve cells,? Meletis said.

Upon injury, ependymal cells proliferate and migrate to the injured area, producing a mass of scar-forming cells, plus fewer cells called oligodendrocytes. The oligodendrocytes restore the myelin, or coating, on nerve cells? long, slender, electrical impulse-carrying projections called axons. Myelin is like the layer of plastic insulation on an electrical wire; without it, nerve cells don?t function properly.

?The limited functional recovery typically associated with central nervous system injuries is in part due to the failure of severed axons to regrow and reconnect with their target cells in the peripheral nervous system that extends to our arms, hands, legs and feet,? Meletis said. ?The function of axons that remain intact after injury in humans is often compromised without insulating sheaths of myelin.?

If scientists could genetically manipulate ependymal cells to produce more myelin and less scar tissue after a spinal cord injury, they could potentially avoid or reverse many of the debilitating effects of this type of injury, the researchers said.

Provided by MIT

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Friday, April 18, 2008

New Discovery May Aid Treatment of Spinal Cord Injuries

A discovery by researchers at University of Minnesota may provide new insights into how the spinal cord controls walking, and this may pave the way for developing treatments for diseases of the central nervous like Parkinson?s disease and spinal cord injuries.

Led by Joshua Puhl, Ph.D., and Karen Mesce, Ph.D., in the Departments of Entomology and Neuroscience, the study has found a possibility that the human nervous system, within each segment or region of spinal cord, may have its own unit burst generator to control rhythmic movements such as walking.

The researchers chose to study a simpler model of locomotion in the medicinal leech, and this uncovered the residing spots of these unit burst generators and it also showed that each nerve cord segment has a complete generator.

It was discovered that a neuron triggers to set off a chain reaction that gives rise to rhythmic movement and the moment those circuits are turned on, the body essentially goes on autopilot.

The researchers mainly focused on the segmented leech for study as they have fewer and larger neurons, making them easier to study.

For most of us, we can chew gum and walk at the same time. We do not have to remind ourselves to place the right leg out first, bring it back and do the same for the other leg. So how does the nervous system control rhythmic behaviors like walking or crawling, said Mesce.

The study also discovered that dopamine, a common human hormone, can turn each of these complete generator units on.

Because dopamine affects movement in many different animals, including humans, our studies may help to identify treatments for Parkinsons patients and those with spinal cord injury, said Mesce.

The study was published online in the Journal of Neuroscience.

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Tuesday, April 08, 2008

Nanotechnology May Help Reconnect Nerves

U.S. researchers say they have created a nano-engineered gel that can enable severed spinal cord fibers to regenerate and grow.

Mice paralysed by spinal injuries have been able to walk again thanks to a treatment developed by scientists in the US. The therapy uses proteins that self-assemble into nano-fibers at the site of the injury, encouraging nerves to regrow.

Spinal cord injuries often lead to permanent paralysis and loss of sensation because the damaged nerve fibers can't regenerate, Northwestern University scientists said. Although nerve fibers or axons have the capacity to re-grow, they don't because they're blocked by scar tissue that develops around the injury.

The nanogel developed at the university's Feinberg School of Medicine inhibits formation of scar tissue and enables the severed spinal cord fibers to regenerate and grow, the scientists said.

The gel is injected as a liquid into the spinal cord and self-assembles into a scaffold that supports new nerve fibers. When the gel was injected into mice with a spinal cord injury, after six weeks the animals had a greatly enhanced ability to use their hind legs and walk.

"It's important to understand that something that works in mice will not necessarily work in human beings," said study leader Dr. John Kessler, who noted that if the gel is eventually approved for humans, a clinical trial could begin within several years.

The research is reported in the Journal of Neuroscience.

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Sunday, February 17, 2008

Spinal Cord Injury Regeneration Hope

Scientists believe they are close to a significant breakthrough in the treatment of spinal injuries.

The University of Cambridge team is developing a treatment which could potentially allow damaged nerve fibers to regenerate within the spinal cord.

It may also encourage the remaining undamaged nerve fibers to work more effectively.

Spinal injuries are difficult to treat because the body cannot repair damage to the brain or spinal cord.

Although it is possible for nerves to regenerate, they are blocked by the scar tissue that forms at the site of the spinal injury.

Scientists believe they are close to a significant breakthrough in the treatment of spinal injuries.

The Cambridge team has identified a bacteria enzyme called chondroitinase which is capable of digesting molecules within scar tissue to allow some nerve fibers to regrow.

The enzyme also promotes nerve plasticity, which potentially means that remaining undamaged nerve fibers have an increased likelihood of making new connections that could bypass the area of damage.

Boosts rehabilitation

In preliminary tests, the researchers have shown that combining chondroitinase with rehabilitation produces better results than using either technique alone.

However, trials have yet to begin in patients.

Lead researcher Professor James Fawcett said: "It is rare to find that a spinal cord is completely severed, generally there are still some nerve fibers that are undamaged.

"Chondroitinase offers us hope in two ways; firstly it allows some nerve fibers to regenerate and secondly it enables other nerves to take on the role of those fibers that cannot be repaired.

"Along with rehabilitation we are very hopeful that at last we may be able to offer paralyzed patients a treatment to improve their condition."

'Ground-breaking'

Dr Yolande Harley, of the charity Action Medical Research which funded the work, said: "This is incredibly exciting, ground-breaking work, which will give new hope to people with recent spinal injuries."

Paul Smith, of the Spinal Injuries Association, said medical advances meant that spinal injuries had ceased to be the terminal conditions that they often once were, but they still had a huge impact on quality of life.

However, he warned against raising expectation before the treatment was fully tested on patients.

He said: "What often happens in a clinical setting is that you don't get to see the results you would have liked."

In the UK there are more than 40,000 people suffering from injuries to their spine, which can take the form of anything from loss of sensation to full paralysis.

The average age at the time of injury is just 19.

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Thursday, February 07, 2008

Could a Spinal "Bypass" Reverse Paralysis?

A breakthrough in spinal surgery yesterday offered hope to victims of paralysis.

The technique, which has been tested on rats, involves bypassing damaged tissue in the spine.

This allows signals to travel across injured areas, New Scientist reports.

Dr John Martin and his colleagues at Columbia University in New York have so far tested the procedure only on rodents. They selected a motor nerve branching from the healthy cord above the injury and cut it away from the abdominal muscle to which it is normally attached.

They then stretched the free end across the injured section of spinal cord and used a protein "glue" to fix it.

Two weeks later the team found that the graft had sprouted new extensions which had begun to form connections - or synapses - with the motor nerves in the isolated lower spine.

Zapping the spinal cord above the injury made the lower limbs of the rats twitch - showing motor signals had started once again to pass along the entire length of the spine.

The researchers say removing the nerve from the abdominal muscle did not appear to cause any major side effects and suggest this is because nearby nerves pick up the slack.

Fellow neuroscientist Dr Reggie Edgerton, of California University, said the approach had considerable clinical potential but added that it was too early to tell whether it would work in humans.

Dr Marie Filbin of the City University of New York cautioned that it may not be possible to "reprogramme" a nerve that normally connects to an abdominal muscle to transmit the sophisticated signals needed to produce fine, controlled movements.

But Dr Martin, who presented his study at the New York State Spinal Cord Injury Research Program Symposium, said: "What we want to do is plug in new connections to bypass the damaged region."

He believes that - with a little surgical assistance - spinal cord nerves above an injury could be capable of making such connections with nerves lower down the spine.

He said: "We know the nerves can make new connections to muscle so we asked whether it's possible for them to also connect with spinal cord neurons isolated through injury."

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Friday, September 07, 2007

Skin Stem Cells Used to Mend Spines of Rats

Toronto research shows injured subjects walking better after injections

A Toronto-led team of researchers has found a way to use stem cells derived from skin to treat spinal cord injuries in rats.

The finding lends promise to the idea that stem cells could one day be used to heal spinal cord injuries in humans, helping thousands to walk again.

Injured rats injected with skin-derived stem cells regained mobility and had better walking co-ordination, according to the study published yesterday in the Journal of Neuroscience. The skin-derived stem cells, injected directly into the injured rats' spinal cords, were able to survive in their new location and set off a flurry of activity, helping to heal the cavity in the cord.

Freda Miller, a senior scientist at The Hospital for Sick Children and lead author of the study, said skin-derived stem cells have some advantages over other stem cell types. Scientists who use skin to generate stem cells do not need to use embryos, for example, and skin-derived stem cells can potentially be harvested from patients themselves, she said.

"You can imagine a scenario for people with spinal cord injuries, that maybe, just maybe, we could take a piece of their skin, grow the cells up and transplant them (the patient) with their own cells," she said. "You wouldn't have to give them immunosuppressive drugs. That's a tremendous clinical advantage if it comes true."

Miller and her colleagues from The Hospital for Sick Children and the University of British Columbia have been exploring the possibilities of using skin to derive stem cells since 2001.

Over the course of their research, the team found that skin-derived stem cells share characteristics with embryonic neural stem cells, which generate the nervous system. They also showed skin-derived stem cells can produce Schwann cells, a cell type that creates a good growth environment to repair injured central nervous system axons ? the long nerve cell fibres that conduct electrical impulses between nerves ? and that these Schwann cells put down myelin along the injured spinal cord. Like the insulation around an electrical cord, myelin wraps around nerves, creating a sheath that helps quickly conduct nerve impulses.

Miller said the next step was to see whether transplanting the Schwann cells directly into spinal cords would help treat injured rats.

To test their hypothesis, Miller and her team generated stem cells from the skin of rats and mice and forced them to differentiate into Schwann cells, which were then transplanted into the rats. After 12 weeks, the rats were able to walk better, with more co-ordination.

Miller said the cells thrived within the injured spinal cord. Before treatment, the injured rats had a cavity in their spinal cord, a result of their injury. But after treatment, Miller said the Schwann cells had created a bridge that spanned the cavity, and helped nerves grow through the bridge.

The next step is to see whether stem cells derived from human skin can produce similar results.

"We are highly encouraged," said Miller.

Story by: Megan Ogilvie

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Monday, August 20, 2007

"Spinal Cord Injuries" on Patient Power with Andrew Schorr

The radio and internet program, "Patient Power with Andrew Schorr" will feature an upcoming program entitled, "Spinal Cord Injuries," featuring a medical expert in the field, David Chen, MD. It airs live online at HealthNet on August 28, 7 p.m. Central Time, and listeners may call in with questions, or send questions via e-mail.

Replays and transcripts will also be available on Patient Power following the live show.

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Thursday, July 26, 2007

Spinal Cord Injury Therapy Developed

U.S. medical scientists have developed a new spinal cord therapy that helps the body permanently recover from such injuries.

Researchers at the Sloan-Kettering Institute for Cancer Research studied rats with crushed spinal cords. The scientists found treatment soon after injury, combining radiation therapy to destroy harmful cells and microsurgery to drain excess fluids, significantly helped the body repair the injured cord.

The scientists, led by Nurit Kalderon, said their findings demonstrate conventional clinical procedures hold promise for preventing paralysis due to spinal cord injuries. Currently there is no cure for human spinal cord injury.

"This research opens the door to developing a clinical protocol for curing human spinal cord injuries using conventional therapies," said Kalderon.

The study, supported by a grant from the National Institute of Neurological Disorders and Stroke, appears in the online journal PLoS One.

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Tuesday, May 01, 2007

Doctors Try New Injection To Fight Paralysis

There are currently no effective therapies for spinal cord injuries. But a protein injection may help some patients walk again.

Two years ago, Michelle Robinson was on her way home from work when she was hit by a car.

"All I remember is hearing a loud screeching noise and I remember going, flying up in the air," Michelle said.

The accident left the 42-year-old mother paralyzed. Now she hopes an experimental drug will put her back on her feet.

"It appears that this actually does improve their prognosis," said James Harrop, a neurosurgeon.

Harrop is testing the novel drug called Cethrin to treat spinal cord injuries.

"It's a paste or a jelly that you sort of just spread onto the spinal cord with a little applicator, like a syringe," he said.

Doctors apply the protein during standard decompression surgery to stabilize the spine. The idea is to stop nerve cell death that includes days to weeks after the injury occurs.

"Inside the cell, there?s a nucleus which is controlling sort of this, the auto-regulator of the cell and what it?s doing is it?s telling the cell we don?t want you to function anymore," Harrop said.
Cethrin is designed to interfere with that message by seeping through the spinal cord membrane to cells at the injury site.

"It goes into the cell and it says 'wait a minute'. I don't want you guys going down that path anyways, I want you to stop and I want you to start repairing the cell," Harrop said.

Early trials show the protein therapy is safe. And the results are promising. Michelle says she is both excited and hopeful the new therapy will work for her.

"I say those words because Dr. Harrop told me that he was very hopeful that, you know, maybe one day I would be able to walk again, so I'm very hopeful also."

Doctors caution that Cethrin, also called BA210, is not a magic bullet. But in the study, 31 percent of patients regained some function after being injected with the drug. The study is still enrolling patients. About 253,000 Americans are living with a spinal cord injury. Roughly 11,000 new cases occur every year.

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Tuesday, April 24, 2007

Simple Injection Shows Promise for Treating Paralysis

Paralyzed lab rodents with spinal cord injuries apparently regained some ability to walk six weeks after a simple injection of biodegradable soap-like molecules that helped nerves regenerate.

The research could have implications for humans with similar injuries.

"It will take a long time, but we want to offer at least some improvement, to improve quality of life for people with these injuries," materials scientist Samuel Stupp at Northwestern University in Evanston, Ill., told LiveScience. "Anything would be considered a breakthrough, because there's nothing right now."

The soap-like molecules contain a small piece of laminin, a natural protein important in brain development. After these molecules are injected into the body, they react with chemicals there, assembling themselves instantly into scaffolds of super-thin fibers just six billionths of a meter wide, roughly a hundredth a wavelength of orange light. They biodegrade after roughly eight weeks.

The scientists experimented with their molecules on dozens of mice and rats that experienced spinal cord injuries that paralyzed their hind legs, "the kind of very hard blow people might experience after falling off skiing slopes or getting in car accidents," Stupp said. His colleague, neurologist John Kessler, became active in this work after Kessler's daughter was paralyzed in a skiing accident.

After six weeks, damaged nerves regenerated enough for the paralyzed legs of the rodents to regain some ability to walk.

"There's a special scale to monitor how much function they regained, ranging from 0 to 21," Stupp explained. "At 21, function is perfect. At 6 or 7, limbs are just paralyzed, and the mice were just dragging them along. If you go to 9 to 12, the animal can now actually move the limbs. Not perfectly?awkwardly?but they move. So two or three points on that scale makes a huge difference."

"We've been able to go from a 7 to a 9 in the mouse, and in the rat, the highest was 12," he said. The findings are to be presented today at a meeting of the Project on Emerging Nanotechnologies in Washington, D.C.

The researchers are currently in talks with the FDA regarding their work and hope to start phase I clinical trials (for toxicity and safety testing) in humans two years from now, Stupp said. The idea he and his colleagues have for these molecules is to administer them within a day or so after spinal cord injuries, before scar tissue begins to form that can suppress healing. Past experiments have shown these molecules can actually turn neural stem cells (which might otherwise become scar cells) into neurons instead.

"Recovering every function a person had before an injury will probably be very hard," Stupp cautioned. "Even if people couldn't walk, if they could recover bladder function, that'd be a good thing. It's the first thing I'd want to recover."

The researchers now are developing versions of these soap-like molecules that could help with regeneration when it comes to other maladies such as Parkinson's disease, stroke, heart attacks, bone trauma or diabetes.

By Charles Q. Choi

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