Stem cells treat wasted muscles - Dogs with muscular dystrophy walk better after injections.

news@nature.com ^ | 15 November 2006 | Helen Pearson

[neverdem]

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Published online: 15 November 2006; | doi:10.1038/news061113-13

Stem cells treat wasted muscles

Dogs with muscular dystrophy walk better after injections.

Helen Pearson

Golden retriever dogs make a good animal model for muscular dystrophy Rossana Tonlorenzi & Maurilio Sampaolesi, San Raffaele Scientific Institute

An infusion of stem cells scraped from blood vessels has helped dogs with a form of muscular dystrophy to walk more normally, perhaps heralding a treatment for the human disease.

Muscular dystrophies are a group of widespread genetic disorders in which the muscles gradually break down. The most common form, called Duchenne muscular dystrophy, is caused by mutations in a gene called dystrophin and inevitably causes paralysis and death.

Giulio Cossu of the San Raffaele Scientific Institute in Milan, Italy, and his colleagues had previously shown that a type of stem cell called a mesoangioblast, which lives in the walls of blood vessels and can generate muscle cells, can help mice with a form of muscular dystrophy¹. So they set out to study the effect of the cells in an animal model that more closely mimics the human condition: golden retriever dogs with a mutation in their dystrophin gene.

The team extracted the blood-vessel stem cells from normal dogs, grew them to large numbers in the lab, and injected tens of millions of cells into sick dogs in five monthly injections.

Afflicted dogs usually develop troubles walking by 8 months old. But many of the treated dogs did much better; one was still walking well at 13 months of age. The results are published online in Nature².

Cossu says that the team has already identified the equivalent stem cells from humans and that clinical trials could start in a few patients by late 2007. But they will need to test more dogs first. "We're not rushing," Cossu says.

It's uncertain whether this type of treatment can repair heart muscle or the diaphragm, which also fail during muscular dystrophy. Furthermore, it is unclear whether the stem cells might lodge themselves elsewhere in the body and cause unwanted side effects.

Straight to source

Stem cells can travel through the blood, squirming their way out into muscles throughout the body. Rossana Tonlorenzi & Maurilio Sampaolesi, San Raffaele Scientific Institute

By examining the dogs' muscles, the team found that the stem cells had travelled through the blood, squirmed their way out of capillaries and into many muscles throughout the body. There, they had fused with existing muscle fibres, manufactured the missing dystrophin protein and rejuvenated the fibres.

Researchers have been testing other types of stem cell to treat muscular dystrophy, such as ones extracted directly from muscle or bone marrow. But these cell types have either revived only a few muscle fibres or needed to be injected directly into each muscle.

The real advantage of the mesoangioblast cells is that they can be injected into the bloodstream and swim to most muscles in the body, says neurologist Thomas Rando who studies muscular dystrophy at Stanford University, California.

Stem cells have been touted as the way to regenerate numerous failing tissues — but none have yet become tried-and-tested human treatments. Rando says that muscular dystrophy is a good disease to target, because the replacement cells only have to fuse with existing muscle fibres, rather than spawning brand new cells or tissues.

Tailor-made

In terms of treating human disease, cells donated from another person are not ideal because a patient has to take lifelong immunosuppressant drugs to avoid rejection.

Cossu's team looked at one possible solution to this problem: they extracted stem cells from sick dogs and used gene therapy to insert a working copy of the dystrophin gene into these cells. They then injected the dogs with their own, 'fixed' cells.

Dogs treated this way began to manufacture dystrophin, but they did not have improved symptoms. Cossu thinks the results might be improved by using a different version of the dystrophin gene (which is notoriously difficult to handle because it is so large - in humans it is more than 2.5 million base pairs long, and by far the largest gene in the human genome).

From all angles

Other methods to treat muscular dystrophy are nearing clinical trials. Some groups are trying to deliver a replacement dystrophin gene to all muscles using a virus. Others are working on drugs that encourage a cell to ignore the mutation in its gene and manufacture a correct form of dystrophin protein.

"I think we may be approaching a time when we'll see multiple approaches combined," says muscular-dystrophy researcher Jeffrey Chamberlain of the University of Washington, Seattle.

Visit our newsblog to read and post comments about this story.

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References

1. SampaolesiM., et al. Science, 301. 487 - 492 (2003). | Article | PubMed | ISI | ChemPort |
2. SampaolesiM., et al. Nature, published online doi:10/1038/nature05282 (2006).

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http://news.nature.com//news/2006/061113/061113-13.html

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[neverdem]

SC Ping

[Mamzelle]

South Carolina?

[neverdem]

stem cell

[acapesket]

I heard this earlier, I believe them thar stem cells were from a "non - embryonic" line. I could be greatly mistaken, making dinner and in and out of the room.. somebody please.. prove me right for once!
Just jokin.. I thought this was true but then FOX did that whole stupid Iranian thing With the Schlepp.. curled eyelashes at 7PM..

[Mamzelle]

Well. Just so it's not Southern California--bump. Interesting article.

[Tuscaloosa Goldfinch]

If I am reading this article correctly, there is no indication that the treatment could reverse the effects of MD, correct?

[twhitak]

An infusion of stem cells scraped from blood vessels...

Sounds like a NON-embryonic source to me. An embryo (at the stage where stem cells are harvested) would not have blood vessels.

[fortunecookie]

An infusion of stem cells scraped from blood vessels

Notice these are stem cells scraped from blood vessels. Not harvested from embryos or partially aborted babies. And they worked! This is good news! I'd like to see Michael J. Fox endorse this kind of stem cell research.

[mountn man]

Must be adult or non-embryonic stem cells.

1-Anything I've heard is that ALL advances in SC have been along adult stem cell lines. There have been 70 or 72 major advances or breathroughs with adult stem cells.

2-There have been 0 (ZERO) advances along embryonic lines. In fact emryonic stem cells are believed tohave caused cancer and tumors and other problems.

Adult stem cells 70 Embryonic stem cells ZERO

3-If embryonic stem cells had been used, EMBRYONIC stem cells would have been stipulated and mentioned with flashing lights and fanfare. But since they're more than likely ADULT stem cells, they just use the generic "stem cell" , thus blurring the line between the two, in an attempt to confuse the unlearned and unwashed.

[neverdem]

Major advance in tissue engineering growing heart valves

Bird Flu Mutations Likely To Trigger Pandemic Identified

Scientists: Pollution could combat global warming

Forest growth is encouraging, say researchers (Bush's fault?)

FReepmail me if you want on or off my health and science ping list.

[mountn man]

If I am reading this article correctly, there is no indication that the treatment could reverse the effects of MD, correct?

I heard about this on the radio today or yesterday. If I remember correctly, the progresses would be reversed if treatments did not continue. But as long as treatments continued, progress was seen.

I also believe I heard them say that they were looking for OK to start human testing.

As long as side effects are minimal, I can't see why someone would care if treatments were ongoing.

[Tuscaloosa Goldfinch]

I have a friend who has a son with MD. He's in a wheelchair now, and I was just wondering if this type of treatment, in addition to slowing the progression of the disease, might even reverse some of the effects.

[momfirst]

You are correct - they are NON-embryonic stem cells. I had a very long discussion with a co-worker today regarding this. We work in cancer research and are just appalled that these types of advances aren't clearly identified as non-embryonic. There are so many like this and next to nil on the embryonic side. Yet the MSM still likes to make it seem there is only one type of stem cell by burying it deep in the article. *sigh* It's just one of those pet peeves we have....

[mountn man]

I have a friend who has a son with MD. He's in a wheelchair now, and I was just wondering if this type of treatment, in addition to slowing the progression of the disease, might even reverse some of the effects.

I believe the article does mention that dogs were able to walk, and that it did improve things on them. I don't believe they are permanent reversals, UNLESS treatments are continued.

I am not a doctor....but I did stay at a Holiday Inn once.

By the way, I have a friend who I met our freshman year of highschool, almost 30 years ago. We studied martial arts together, I stood up in his wedding, and the last almost 20 years, I've watched him go from 5'11" 180lbs, to being in a wheel chair with arms no bigger than my wrists, and legs no bigger than my arms. All because of MD. So I hope that this treatment is promising.

[denydenydeny]

Has any MSM story about some new miracle stem cell cure EVER used the a-word in the headline?

I would bet money that if any such headlines exist, they are outnumbered literally a thousand to one by headlines that say only "stem cells."

[Tuscaloosa Goldfinch]

I'm sorry about your friend. That's really sad, and must be hard to see. I know the young man I mentioned was fine when he was really small, and I guess he's about 17 now. It would be great if something could be done to improve their mobility and strength.

[theymakemesick]

If they were embryonic stem cells the article would have said so in every other sentence.

[right-wingin_It]

Yes, "non-embryonic"...(and you wold thinc that point could have been made in the news reports on this study)

[hocndoc]

Amazingly, or not, the news coverage dismisses the importance of this study and no one seems to have done a simple Google search on the history of the research. I reviewed some of both in my blog* on Thursday.

*Or, as I prefer to call it, my editorial comment on the day's Bioethics News.)