Posted on 06/25/2008 12:04:02 PM PDT by NormsRevenge
SAN DIEGO – A team of San Diego scientists has moved embryonic stem cell research a step closer to helping repair the brains of stroke victims and people with diseases such as Parkinson's and Alzheimer's.
The team, led by the Burnham Institute's Stuart Lipton, figured out how to coax the embryonic stem cells of mice to become nerve cells that, when transplanted into a mouse brain damaged by stroke, link themselves to the existing network of neurons.
The mice showed therapeutic improvement, and none of them developed tumors, which has been a problem associated with the implantation of stem cells, according to the article published today in The Journal of Neuroscience.
Lipton said that since submitting the article several months ago, his team has been able to achieve the same result with human embryonic stem cells implanted in mice.
Conditions such as stroke, Alzheimer's, Parkinson's and Huntington's disease destroy brain cells, causing speech and memory loss and other debilitating consequences. In theory, transplanting neuronal brain cells could restore at least some brain function, just as heart transplants restore blood flow.
“This is a step in the right direction for producing specific nerve cells for cell replacement therapy,” said Arnold Kriegstein, head of the stem cell program at the University of California San Francisco.
Embryonic stem cells, present just days after fertilization, ultimately evolve into the more than 200 different cell types in the body. It is this morphing power of the cells that many people hope may one day be harnessed to create cures for some of society's worst diseases.
“To move forward with stem cell-based therapies, we need to have a reliable source of nerve cells that can be easily grown, differentiate in the way that we want them to and remain viable after transplantation,” Lipton said.
But one of the daunting challenges currently faced by scientists is figuring out exactly what biological signals and processes cause embryonic stem cells to evolve into specific cell types.
Lipton, who is a researcher and clinical neurologist who treats patients with diseases in the brain, has been working for more than 15 years to figure out how neuronal brain cells are created.
His research found that a key ingredient in the process is a protein in the body called MEFC2. This so-called transcription factor links to the genes in the stem cell and signals them to turn the cell into a neuronal cell only, Lipton said.
Previous research trying to produce neurons from embryonic stem cells has resulted in the creation of glial cells, a type of brain cell that provides support to neurons, said Steven Goldman, a neurologist who is chief of the division of Cell and Gene Therapy at the University of Rochester Medical Center in New York.
Goldman said Lipton's team has created a very general group of neurons. The study does not break down the kinds of specific neuronal cells that were created, although that work must be done at some point for this research to move closer to therapeutic applications, Goldman said.
Also unknown from this study is exactly how much control scientists will have in directing the stem cells to become one of several different neuron cell types in the brain, Goldman said. And it remains to be seen if all the research in mice applies to humans, he said.
However, it is significant that the neurons survived, had an electrical charge and showed signs of being connected to the brain's network, Goldman said.
Nerve cells of many different types exist in the brain and perform different functions in different brain circuits. The study didn't uncover just how these grafted cells may influence brain activity, Kriegstein said.
In fact, changes in inflammation of the damaged area or growth factors connected with the implanted cells could be responsible for part or all of the behavioral improvement documented in the transplant recipients, he said.
“The brain is a very complicated and sophisticated organ, and it is likely that promoting true repair will require a solid understanding of exactly what cell grafts such as these are contributing to the injured brain,” Kriegstein said.
Goldman said that at this stage of research, it's unlikely that Lipton's work would be used for human clinical therapies because the long-term effects of the genetic modification of the cells is unknown.
“However, this is an extraordinarily important tool from a research standpoint, and Stuart's work brings significant new insights into how neurons are generated,” Goldman said.
Members of Lipton's team listed as authors of the article include other scientists at the Burnham Institute for Medical Research, as well as researchers from the Scripps Research Institute and Lipton's teenage son, Jeffrey, who was taught by lab members how to record and keep track of the cells.
Researchers from the Salk Institute and University of California San Diego also contributed to the project, which was funded by the National Institutes of Health.
The work Lipton's team has done more recently, which involves human embryonic stem cells, was funded by the California Institute for Regenerative Medicine through a four-year grant. That funding is part of the state's $3 billion investment in stem cell research.
Background: Conditions such as stroke and Alzheimer's, Parkinson's and Huntington's disease destroy brain cells, causing speech and memory loss and other debilitating symptoms.
What's changing: A team of San Diego scientists has coaxed the stem cells of mice to become nerve cells in the brain, linking themselves to the existing network of neurons.
The future: The finding lays the groundwork for further research into how stem cells could be used in human therapies. In theory, transplanting neuronal brain cells could restore at least some brain function.
While this study appears to be on mice only, who knows, maybe rats will also benefit, so there may truly be HOPE for liberals too.
Who’da thunk embryonic stem cells from mice might offer promise for sufferers of brain damage?
ping
Let me know when they come up with the cure for us functioning psychopaths.
I suggest we wait until the embryo is 18 and let it decide if if wants to die or not.
I suggest we wait until the embryo is 18 and let it decide if if wants to die or not.
I find that to be ... to be ... errr ... what's the word?
Frankenstein is alive!
ASC will work better, and has the added benefit of not being immoral.
I saw an article here not too long ago where they were taking ADULT stem cells from the interior of mouse noses, and inserting them in the brains of mice, and significantly reversing the Michael J. Fox disese.
Lets plug this sentence into the Free Republic Main Stream Media News Analyzer...
beep
beep
beep
DING!
Here are the results:
Input: A team of San Diego scientists has moved embryonic stem cell research a step closer...
Meaning: Nothing was actually accomplished by the scientists that can be used by humans. Since embryonic stem cells are a proven carcinogen in humans, the author of the sentence must have an agenda. There is a 90% chance that the author is trying to justify abortion by keeping hope alive that somehow, some way all these dead babies parts can be used for something.
but but but.
tumor free ..
or so they make it sound.
So when a Demorat is told to “go grow a brain” they can use this as an option now?
Ahh mice brains again...ping me when they test it on pig headed, asshole, sexist McCain Haters. Some would say I might find that interesting.
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