Jan 20 2009
Stem Cells for Stroke
Dr. Keith Muir is leading a trial at the Southern General Hospital in Glasgow that is about to test stem cells as a possible therapy in stroke. As reported by the BBC, the trial is set to enroll 12 subjects and will last for two years. While this will be far from a definitive trial, it will explore the basic safety and potential of this approach.
Strokes occur due to lack of blood flow to a part of the brain. Those brain cells are injured – those at the core of the stroke die while those around the periphery (which is usually much larger in volume than the core), which are getting some blood flow, may or may not survive. About a third of stroke patients recover either fully or nearly so, while the rest either die or suffer permanent neurological deficits. The symptoms of a stroke depend upon what part of the brain is damaged.
Dead brain cells do not come back. Initial recovery results from damaged but not dead neurons recovering their function. After that, deficits are due to dead brain cells and are considered permanent. However, further recovery is possible (although slow – months to years) due to the brain’s plasticity. The brain can rewire around damaged section, and form new pathways. In addition, healthy cortex can take over the lost functions or compensate for them to some degree. This takes a great deal of time and effort, which is part of the function of the long course of rehabilitation that often takes place following a stroke.
In recent years it has also been discovered that there are neuronal stem cells even in the adult brain. These cells are activated whenever part of the brain takes on a new task that requires new pathways. This may be why undertaking novel mental tasks later in life may stave off degenerative brain diseases.
But the brain’s plasticity has its limits. When large parts of the brain are damaged by stroke the lost functions can only be partially compensated for. Further, after such a recovery the brain has lost some of its reserve. It is not uncommon, for example, for the symptoms of a stroke that one has recovered from to return under stress – sleep deprivation, emotional stress, or a mild fever.
Stem cell therapy holds the promise of implanting additional neuronal stem cells into a patient’s brain following a stroke, and then these stem cells contributing to recovery. In effect they would dramatically increase the plasticity of the brain, the new cells being recruited to form new pathways to take over for lost function. Because the brain already is a plastic organ – it can direct the neurons to form new and meaningful connections – this is a very plausible scenario.
But of course plausibility is not enough. There are many hurdles to such a technology. We need to get stem cells to become neuronal stem cells, to survive after transplantation, and to become recruiting into repairing the brain. Further, we need to make sure that these introduced cells do not just grown into a tumor. That is the reason for the caution, and why clinical trials of stem cells in humans have been so slow.
Also slowing the process are the controversial moral concerns. Such studies have not taken place in the US because the FDA has not approved any such trials. Further, George Bush’s ban on making new stem cell lines and the limitations on federal funding have greatly impeded stem cell research here. Other countries have tried to take advantage of this opening and take the lead in this new technology. Korea was thought to be in the lead for a while, but then the fraud scandal greatly set them back. Now the UK is hoping to take the lead. Although Obama is likely to almost immediately get rid of the Bush Administrations constraints on stem cells, the controversy will not go away and it will take years for American research to recover.
Meanwhile, opposition to stem cell research among the religious right remains strong. In response to this current study, a spokesperson for Society for the Unborn Child is quoted as saying:
“It involves cannibalising an unborn child. It is unethical in every way – killing one member of the human race to help another. We are totally opposed to this.”
Extreme rhetoric such as this does not foster much hope for a reasonable dialogue.
Then again, there is research that is progressing very nicely into the technology to transform an adult derived cell into a stem cell – so-called induced pluripotent stem cells. A team in Japan discovered that changing only four genes is all that is needed to induce pluripotency. Recently a team in Boston was able to duplicate these effects with a single viral vector – one virus to implant all four genes. If this technique pans out it could end the controversy surrounding embryonic stem cells completely.
There are a lot of “ifs,” but that’s why it’s research. Twenty or thirty years from now people might be wondering “what ever happened to stem cells, remember them?” Or they might wonder “what did people do before stem cell therapies?” as if such a primitive existence is beyond their imagination. I certainly hope it’s the latter, and I think it’s worth the research dollars to find out.
32 Responses to “Stem Cells for Stroke”
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Regarding neuroplasticity, Steve, what did you make of the case of Paul Bach-y-Rita’s father, Pedro, who, according to the literature, fully regained all of the motor functions lost after a stroke even though his autopsy seven years after the stroke showed that 97% of the nerves that ran from his cerebral cortex to his spine were destroyed? I can’t help but suspect that either the recovery or the damage have been exaggerated in some way, as it just seems too fantastic (perhaps not deliberately but maybe more as a result of the plasticity of memory than the plasticity of the brain), but I might be underestimating the abilities of the brain to reorganise itself.
I’m puzzled by the logic of the anti stem cell people. Generally isn’t it a choice of harvesting the cells or flushing them down the drain.
It’s a religious philosophy consideration and not amenable to logic. They oppose anything that seems to them to ‘play’ with life, which they consider sacred. Politically, they regard it with the same disdain as abortion rights and fight anything they perceive to be destruction or misuse of human life, lost benefits be damned. I know, I know, but it needn’t make sense to logic, only to held beliefs.
DA – Well, life is sacred to such religious philosophies (or so they claim) except for when they deem it not to be – such as in the case of capitol punishment or killing non-Christians or blowing up clinics and so on. So, their claim that life is sacred to them is belied by their actions.
Fifi – Life isn’t sacred to Christians. Innocent life is sacred to Christians. Capitol punishment does not apply to Innocent life. Christians haven’t been given carte blanche to kill non-Christians since the Inquisition…so that’s irrelevant to modern christians. Likewise, how many clinics have been blown up in the last decade? My research shows that there were 24 murders or attempted murders between 1989 and 2004. Yeah, that’s a command from on high there. Truth is, that’s extremism that you can find in any philosophy. Atheists have killed millions based on their philosophy…nobody’s hands are clean.
I’m not personally religious…but don’t act like a fundie to fight the fundies.
If the stem cell procedure proves effective, is it plausible that a similar treatment in undamaged brains could be used for cognitive enhancement?
calinthalus – Right….so you’re saying that it’s okay for Christians to kill anyone they don’t consider “innocent”? I’m assuming you think beating up and killing homosexuals is also okay according to Christian values since they’re sinners and deserve to die because you don’t consider them “innocent”?
For someone who claims they’re “not personally religious” you seem an aweful lot like an apologist for Christian Fundamentalists and seem quite happy to justify murders by Christians who decide to set themselves up as judge, jury and executioner of those who they personally belief not to be “innocent”. Strange that you share these Fundie beliefs but claim you’re not “personally religious”!
With all due respect, calinthus, your statement about atheists killing millions based on their philosophy is a non sequitur at worst and misleading at best. Atheism is the lack of belief in a god/gods, so if they kill millions due to their atheism, they also do it due to all of the other things that they don’t believe in. I don’t hear you criticizing aunicornists or afairyists of killing in the name of their lack of belief.
Sorry Fifi, I assumed what I said would be taken at face value…not dumped on the alter of attack. How is it you assume I think beating up and killing homosexuals is OK? Because it fits into your presuppositions. Continue on.
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To Steve Page. I disagree in some cases. Lenin/Stalin had millions of religious people killed because they were religious. They were killed because of the dogmatic attachment of atheism to communist doctrine. Now, it could be argued that the atheism was secondary…and that control was the ultimate goal. However, I’ve read history papers which made the same claims in regards to at least two of the Crusades.
It would be ridiculous to assume that when an atheist kills, it is strictly because they are atheist. I just ask for the same idea applied regardless of belief. It is very rare over the last 100 years that a Christian killed someone because they were a Christian. There are examples…but there are examples in both camps. The majority of times that people kill it is because of either passion, greed, or mental defect. These things know no religious (or lack thereof) bias.
I just think it’s dangerous to paint with the wide brush I see.
No, you specifically said that only killing “innocent” people is wrong according to your take on Christianity and Christian ethics regarding murder (so the death penalty and killing doctors doesn’t count as murder but is an order from “on high”). Since homosexuality is considered a sin (as is abortion) and homosexuals aren’t considered “innocent”, then your logic about what is and isn’t justifiable killing according to Christians leads to the logical conclusion that murdering homosexuals is okay because they’re also sinners. Of course, Islamic fundamentalists believe exactly the same thing, which is why they routinely execute homosexual people.
Now, there do exist Christians who aren’t Fundies but they’re not the one’s trying to impose their religious beliefs on everyone else and who try to justify killing people who they don’t agree with and want to control in the name of their “god”.
You also assumed I was stating that their beliefs are correct…which I did not. Hell, I’ve given my own money to Stem Cell research.
The problem is, the vast majority of Christians do not believe killing, or beating, or otherwise bothering abortion doctors or homosexuals is right. It was your contention in your original post that christians don’t believe it is wrong to kill a non-christian or an abortion doctor etc.etc. The fallacies in your posts are numerous.
You are first using ad-hom and strawmen against me personally. You do this to continue using Slippery Slope, and False Continuum in regards to mainstream and extremist christians. It is absurd to insist that the majority of christians believe they are in their rights to kill a “sinner”. This would be your largest fallacy…the Reductio ad absurdum.
calinthalus wrote “Life isn’t sacred to Christians. Innocent life is sacred to Christians. Capitol punishment does not apply to Innocent life. Christians haven’t been given carte blanche to kill non-Christians since the Inquisition…so that’s irrelevant to modern christians. Likewise, how many clinics have been blown up in the last decade?”
So you claimed that only “innocent” life is sacred to Christians so therefore it’s okay to kill people Christians don’t like or consider “innocent” according to Christian beliefs and values. This is your claim, not mine. By your own logic, killing homosexuals is okay according to Christian values. You seem to be conveniently forgetting that President Bush was waging a holy war – didn’t he actually call it a crusade? – so the crusading days of using “god” to justify murdering people who are different are hardly over.
Sure there are Christians who aren’t fundamentalists but they’re not the ones objecting to stem cell research on the grounds that it’s “murder”. I have oodles of respect for Christians who speak up against homophobia in their church or who have moved beyond their xenophobia (though they are often disparaged and run out of town by their fellow Christians), so far you’re just being an apologist for Fundamentalist Christians and tyring to justify the illogic of their stance so whether you did or didn’t personally donate money to support stem cell research is pretty irrelevant.
I see no reason to give special privileges or considerations to religion on a science-based medicine blog discussing stem cell research.
So you claimed that only “innocent” life is sacred to Christians so therefore it’s okay to kill people Christians don’t like or consider “innocent” according to Christian beliefs and values. This is your claim, not mine. By your own logic, killing homosexuals is okay according to Christian values.
Correct, I claimed that only “innocent” life is sacred to Christians. However, that doesn’t mean it’s okay to kill people they don’t consider “innocent”. Even by their standards. They believe that innocents should be protected at all costs. Non-innocents make their own beds and should lie in them. It is not up to the individual christian or church leader to dictate the fate of non-innocent non-christians. It says so right in the book they put all that stock in.
Sacred or not sacred does not dictate what can or cannot be killed. I assume you don’t believe any life is technically sacred…but you also obviously do not believe that gives you the right to take life as you see fit.
It’s also not just Christian Fundamentalist that are anti-science, the Vatican is against embryo stem cell research (so theoretically, at least, all good, observant Catholics are too). Then there’s that nasty little element of xenophobia yet again….
http://www.jewishsf.com/content/2-0-/module/displaystory/story_id/9872/edition_id/189/format/html/displaystory.html
I’ve got to credit you on your attempt to diminish murdering doctors as being trivial and not a big deal because you personally seem to think the body count isn’t a big deal.
I’ve got to credit you on your attempt to diminish murdering doctors as being trivial and not a big deal because you personally seem to think the body count isn’t a big deal.
I did not diminish it, I simply refuse to accept that it is a mainstream christian belief that their murders are acceptable. You used it as a specific example about the beliefs of christians at large. Since the majority of citizens of the U.S. are christians you would predict that if your contention were true, the number would be much higher. The number is incredibly low…and while each death is tragic…it does not qualify as evidence for your claim.
I made no claims as to anti-science or not. Most people in general are afraid of science. People fear what they don’t understand. I don’t think that’s specific to Christianity…but I’m sure it’s more representative in religious people than non-religious. Most confirmed atheists are educated. I don’t know if this is causation or correlation. However, either works in this instance. It is enough to say that the majority of atheists will embrace new technology and scientific discovers at a wide margin over their religious counterparts…regardless of background or socio-economical status. No idea what that has to do with killing doctors or homosexuals…but whatever.
calinthus – Are you a mainstream Christian? Is that why you’re here to defend Christians and Christianity rather than discuss advances in stem cell research? You seem awefully invested in buffing the image of “mainstream” Christians and minimizing the influence of Protestant Fundamentalists and the Catholic Church (even though they’re the ones who have been fighting against stem cell research in the US and claiming it’s murder so the Christians relevant to embryonic stem cell research since there are no Christians standing up advocating stem cell research in the US – though I’m certainly open to being introduced to some if they exist).
You don’t have to be the person pulling the trigger to be involved in killing doctors, all those who support the killers through funding them and who promote the idea that it’s okay to kill “sinners” do so.
Are you a mainstream Christian?No. By definition a mainstream christian must believe that the bible is the infallible word of god, and that Jesus was god and man all wrapped up in a nice package. I believe neither of these things.
Is that why you’re here to defend Christians and Christianity rather than discuss advances in stem cell research?I believe it was you who first brought christians into this.
Again, I have no idea what the catholic churches stance on science has to do with killing homosexuals. That was a line that you drew.
You don’t have to be the person pulling the trigger to be involved in killing doctors, all those who support the killers through funding them and who promote the idea that it’s okay to kill “sinners” do so.Right, so of the 224 million christians in the U.S. (2004 estimate on self-identified christians)…they have killed what, 30 people? Where did the rest of the funding go? Did they have anything to do with 9/11 as well? Did the mainstream church take out building 7?
Actually DA brought up religion and I mentioned Christians (since Christians are the ones who protest stem cell research in the US and who Bush was placating…I could be incorrect and am open to considering evidence but as far as I’m aware there has been no political pressure to ban stem cell research in the US coming from anyone but Christians). Then you jumped in to pontificate and speak authoritatively for both Fundamentalist and mainstream Christians about their beliefs even though you claim to be neither.
The Catholic Church’s stance on science is tied in with their beliefs about what is “natural” and “unnatural” and this is directly related to their stance on homosexuality as being “unnatural” and a “sin”. For someone who is proposing they’re an authority on Christian beliefs but not a believer, you don’t seem to be able to think about it very rationally and see how one belief leads to another. Though considering that religion is irrational, that’s not very surprising that someone who’s an apologist wouldn’t be able to follow the logic to it’s natural conclusion or apply it evenly.
Exactly what does 9/11 have to do with this apart from it most likely being religious fundamentalists that are responsible and it most likely being part of a holy war? Ergo more religiously motivated violence and more murder commited in the name of a god by more religious people who think they should be able to impose their values on everyone else and kill people they’ve judged not to be “innocent”.
The Catholic Church’s stance on science is tied in with their beliefs about what is “natural” and “unnatural” and this is directly related to their stance on homosexuality as being “unnatural” and a “sin”. For someone who is proposing they’re an authority on Christian beliefs but not a believer, you don’t seem to be able to think about it very rationally and see how one belief leads to another.
And where does it say you can beat a sinnner? Or kill one? That was your claim…not that they were seen as sinners or unnatural…but that it was okay to kill/beat them. How is seeing something as a sin lead to the freedom to kill the person that sinned? Especially considering their book specifically says they shouldn’t do it.
Sure, it was used that way hundreds of years ago, but that practice has been on the wane since the Salem witch trials. Those few that have used it as such in my lifetime were condemned by secular as well as religious authorities of their own societies.
I’m an authority only in that I’ve at least read their “holy” book, which is more than I can say for the majority of believers. I read it once when I was a believer (I was a christian for a grand total of 2 years around the time of the birth of my first child who is now a junior in high school). I’ve studied their teachings as well as that of several other religions. I was seeking religion when I was young and settled on Christianity when I was 18. I eventually abandoned the search altogether, but I still retain what I read and studied.
Have you read the bible? Luther? Wesley? I don’t mean to make an argument from authority here, but it seems kind of odd to knock someone for having studied a subject.
Exactly what does 9/11 have to do with this apart from it most likely being religious fundamentalists that are responsible and it most likely being part of a holy war?That was me being facetious in reaction to your claims of secret funding of abortion clinic bombers and such. It all sounded so Roswell that I just wanted to tie it to some other equally ridiculous conspiracy claim.
calinthaluson,
“Fifi – Life isn’t sacred to Christians. Innocent life is sacred to Christians. Capitol punishment does not apply to Innocent life”
I think the official position of the Catholic Church disagrees with you there. The current pope (and the previous one as well) is strongly opposed to capitol punishment in all circumstances. (As much as I hate to toot their horn for them)
Simply reading the bible hardly qualifies anyone to speak remotely authoritatively on Christianity. A large volume of Christian dogma can’t be sniffed out from the bible.
Have YOU read Luther? The man was a horribly strong anti-semite. Try reading “On the Jews and Their Lies”.
Really, the fact is that the people who murdered doctors and who spent a great deal of money lobbying against stem cell research were Christian Americans (here in Canada Dr Morgentaler – who was largely responsible for getting abortion legalized in Canada – was given the countries highest award for public service and we don’t have religious restrictions on medical research). It’s hardly a secret or a conspiracy – it was very overt lobbying and an even more overt government policy based in Christian ideology about “life” and who deserves to live and who doesn’t according to religous beliefs. That you want to pretend that this has nothing to do with Christianity and religion is absurd. Just as absurd as bringing up 9/11 – an event entirely based in religious conflict, not to mention the desire to impose a dogmatic religious ideology on others and make everyone live by their religious beliefs under threat of death – to somehow propose that Christians don’t fund Christian Fundamentalists and to suggest such is tantamount to proposing a conspiracy, is simply absurd. If anything, 9/11 is a great example of crazy religious people who think their faith gives them the right to kill anyone different than them and their god wants them to kill Others.
That said, the Catholic Church is hardly known for its transparency. Nor are Protestant evangelicals for that matter.
I said nothing about Christians considering life to be sacred, therefore anti-stem cell research, and anti-abortion, or anti-anything else that seems to fit that bill. I said “they”, and the collective pronoun refers to extremists or fundamentalists of any religion. In the US Christian extremists would predominate, but there are Islamic and even Jewish groups against it as well.
‘Christianity’ per se has become so, um, ‘sectified’ for lack of a better term, you can find just about any set of values under its umbrella, similar to Islam and Judaism.
Whereas Christianity has been co-opted by many to justify all manner of ugliness, most of the American Christians opposing stem cell research do so out of a certain sincerity, albeit a misinformed sincerity.
Fifi i can understand what calinthalus is saying.
My observation as to why such a passionate and dogmatic approach is taken by Christians on banning of stem-cell reasearch is due to the innocence factor.
I think there exists a great divide between the beliefs of Christians and non-Christians on the issue. Christians believe that a god-given soul resides in everyone, and they believe in an afterlife. With those two beliefs alone it only follows for a Christian to believe in not destroying the embryos for stem-cell research.
For non-Christians, life in biological, and hence the recognision of a living person is subjective. There is also no belief in an afterlife.
So what it comes down to is Christians not wanting to destroy an embryo that has a God given soul in it, especially because it cannot think for it self, and make any decisions ie the innocence factor.
The only way i can think of combating such a dogmatic belief is to argue that their book is not dogmatic on the issue when life begins. Or attempt to show that their whole faith is dillusional. Both examples are hard to acheive because rational and logical approaches are usually secondary to emotionally charged convictions.
Apparently, Britain has “got hope” with the future work of the Glascow team! Reneuron has a challenge to improve the lives of stroke patients with the neuron technology. Based on my very limited understanding of tumors, I think brain cells would reject viruses or other injected cellular material. Would not surgical implanation of neurons alongside other healthy tissue be effective in the brain?
It’s been a while since Immunology class for me, but I think an implantation of cells or viral particles in the brain would have the best chance of not getting graft v. host disease due to the brain/brain stem having a severely reduced immune system. neurons themselves dont have much in the way of fighting off infection. That’s why meningitis can get so bad, so fast. There’s nothing in the enclosed sack that is blocked by the blood brain barrier to fight back the infection. If I’m wrong, someone please correct me.
Also, every time I read fundie I giggle …
Hey I live in Glasgow. Nothing else to say, just thought I’d mention it lol
@Watcher
Look up microglia. They are phagocytic cells found in the brain and the rest of the CNS.
Huh, guess that answers that. I didn’t realize that they had so many overlapping qualities with other immunocytes. And here I thought they were mostly just garbage disposals …
But from some baseline reading, it looks as if there are T-cells in the CNS, but no B cells? It doesn’t look as if that would matter much though with the extra numbers glial cells. But, that does answer my question about graft v host. Since glials can recognize self, they can for sure recognize the foreign matter.
Maybe I can help, Fred. One, I think it’s painting with an unduly broad brush to say “anti stem cell people”. The objection is to creating embryos for the purpose of destroying them to harvest stem cells. That’s just one way to get stem cells, and the only one to which there is, as far as I can see, a principled objection. I’m not religious, but I do happen to agree with this position.
If you assume, as I do, that human life begins at conception (and let’s not argue that point here, but just allow that it’s scientifically defensible) then it is quite logical to object to that specific form of stem cell harvesting. That’s not nearly the same thing as being “anti stem cell”, and it’s not some vague “it ain’t natural” sort of superstition, either. It’s a rationally-held position in that framework.
Back on the topic of the post, I really hope this research pans out. It would be wonderful to see better recovery from stroke. I lost my mother in law to one, and my father in law was largely incapacitated by a later one. I know it’s too late for him, but I feel like I have a dog in that hunt. Thanks for the good post, Dr. Novella.
And now a California company is doing the same with spinal cord injury people. I think it’s reasonable to say that in the next 5-10 years, we could see an end to injury caused paralysis, or at least a treatment for it.
Definitely an amazing time to be scientist!