Regeneration Can Be Achieved After Chronic Spinal Cord Injury

[Christopher]

http://www.sciencedaily.com/releases/20 ... 134620.htm
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Regeneration Can Be Achieved After Chronic Spinal Cord Injury

ScienceDaily (Oct. 28, 2009) —

Scientists at the University of California, San Diego School of Medicine report that regeneration of central nervous system axons can be achieved in rats even when treatment delayed is more than a year after the original spinal cord injury.

"The good news is that when axons have been cut due to spinal cord injury, they can be coaxed to regenerate if a combination of treatments is applied," said lead author Mark Tuszynski, MD, PhD, professor of neurosciences and director of the Center for Neural Repair at UC San Diego, and neurologist at the Veterans Affairs San Diego Health System. "The chronically injured axon is not dead."

While there are more than 10,000 new spinal cord injuries annually in the United States, nearly 250,000 patients are living in the chronic stages of injury. Yet nearly all previous spinal cord injury studies have attempted to stimulate regeneration when treatment is begun almost immediately after injury -- because, in part, scientists considered it very difficult to achieve regeneration at such long time points after injury. None had shown successful regeneration in the late, chronic stages.

Reporting in the October 29 issue of the Cell Press journal Neuron, the UC San Diego team demonstrated successful regeneration of adult spinal cord axons into, and then beyond, an injury site in the cervical spinal cord, the middle region of the neck. Treatment was begun at time periods ranging from six weeks to as long as 15 months after the original injury in rats.

A number of mechanisms create formidable barriers to regeneration of injured axons in chronic spinal cord injury. These include scar formation at the injury site, a partial deficiency in the intrinsic growth capacity of adult neurons, the presence of inhibitors to growth, and, sometimes, extensive inflammation. Chronically injured neurons show a loss of expression of regeneration-promoting genes, and there is progressive degeneration of spinal cord white matter beyond lesion sites -- all contributing to a poor environment for axonal re-growth.

Even under ideal laboratory circumstances, axonal re-growth is complex, requiring a combination of three things: a cellular bridge in the lesion site; a nervous system growth factor to guide axons to the correct target; and a stimulus to the injured neuron that turns on regeneration genes. Using this combinatorial treatment, the research team achieved axonal bridging beyond the original lesion site in rats when treatment was delayed for up to 15 months after the original spinal cord injury. Animals lacking the full combination treatment did not exhibit axonal regrowth.

The scientists also conducted genetic studies to measure how broad sets of genes in cells can be activated when treatment is delayed after injury. They discovered that, despite considerable delays, most genes could still be turned on to support regeneration, indicating that a chronically injured cell can still be "primed" to grow.

The studies were done in sensory systems that relay the sense of touch from the body to the brain. In ongoing studies, the scientists are testing these approaches for regenerating axons that control movement in chronically injured rats.

"Our findings indicate that there is potential for promoting repair of the injured spinal cord even in chronic stages of injury," said Tuszynski. "While the regenerating axons grow for relatively short distances, even this degree of growth could be useful. For example, restoration of nerve function even one level below an injury in the neck might improve movement of a wrist or hand, providing greater quality of life or independence."

Contributors to the study include first authors Ken Kadoya and Shingo Tsukada, UCSD Department of Neurosciences; Paul Lu, UCSD Neurosciences and Veterans Affairs Medical Center, San Diego; Giovanni Coppola and Dan Geschwind, UCLA Department of Neurology; Marie Filbin, Hunter College, NY; and Armin Blesch, UCSD Department of Neurosciences. The study was funded by the National Institutes of Health, the Veterans Administration, the Dr. Miriam and Sheldon G. Adelson Medical Research Foundation, and the Bernard and Anne Spitzer Charitable Trust.

[Christopher]

more attention this gets the more funding and the closer to human trials...

This is quiet important study for chronic injuries because one rat year is equivalent to several human years in terms of research, and not many studies are able to keep a rat suffering paralysis for a whole year due to the labor intensiveness of caring for it for that duration of time.

http://latimesblogs.latimes.com/booster ... odent.html
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Rodent of the Week: Axons regenerate long after injury

October 30, 2009 | 1:00 pm

Rodent Scientists have been working for more than a decade on methods to treat spinal cord injuries by attempting to regrow injured nerves. Some success has been achieved in animals that are treated immediately after the injury.

However, new research shows it's possible to coax the regeneration of nerve axons in rats as long as a year after injury. Axons are the part of the nerve that carries signals away from the nerve body. In the experiment, researchers were able to stimulate the growth of axons in the damaged part of the spinal cord and somewhat beyond the site.

It's difficult to get injured axons to grow because of scar tissue at the injury site, inflammation and chemical processes that inhibit the growth. Thus, the treatment was dependent on a complex and sophisticated process that included a cellular bridge to the injury site, a nervous-system growth factor to guide axons to the correct target and a stimulus to the injured neurons that turns on genes to promote growth.

Using this formula, researchers were able to demonstrate successful regeneration of axons. Rats that did not receive the full combination treatment did not exhibit growth.

"The good news is that when axons have been cut due to spinal cord injury, they can be coaxed to regenerate if a combination of treatments is applied," the lead author of the study, Dr. Mark Tuszynski of UC San Diego, said in a news release. "The chronically injured axon is not dead.

"While the regenerating axons grow for relatively short distances, even this degree of growth could be useful. For example, restoration of nerve function even one level below an injury in the neck might improve movement of a wrist or hand, providing greater quality of life or independence."

The study is published in the journal Neuron.

[Master DIVER TOM]

You know I have read your posts about what is possible and doctors odds on outcome. I think that if a doctor would answer by connecting patients with erbs sould have contact to others who had the operation or treatment for there limiations. Not just taking the word of a doctors odds. You need to know how close you are to a match with your limiation to the patient who had what ever. I hate after 50 yrs it still left up to a doctors opion . In the 1950, some doctor didnt say anything about erbs. They told my mom and me that I might have Poilio . Just my way to reaching out to try to help.

Tom

[Master DIVER TOM]

I think I Might Have a Idea, You Guys, are awsome the way you talk about treatment and operation, You have great information to share. You could buddy up here to, The ones that had a operation or treatment that work may try buddy up with others with close match of both persons limiations . I think maybe this might help . This way you could reach out to each other for help to. Ask a doctor if you might get a bennift from a operation and your buddy here? Just a thought.

Tom