stem cells

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Younger Muscles And Minds: Protein Turns Clock Back In Mice

Nonagenarian Olga Kotelko, left, on her way to victory in her age group in the 100-meter dash at Sacramento State in July 2011. Pat Peterson, right, won a younger age group. (Ken Stone/masterstrack.com, with permission)

Nonagenarian Olga Kotelko, left, on her way to victory in her age group in the 100-meter dash at Sacramento State in July 2011. Pat Peterson, right, won a younger age group. (Ken Stone/masterstrack.com, with permission)

Just about a year ago, Harvard stem cell scientists reported promising news for elderly heart failure patients: In mice, they found, a protein called Growth Differentiation Factor 11 could undo heart damage wrought by aging.

But was it just a heart thing? Or might GDF11 apply more broadly to other ways that we get older but not better?

New research finds that the protein has similarly rejuvenating effects on brains and muscles — though again, only in mice, so it will be years before we’ll know whether humans might see similar benefits. But GDF11 does circulate in the human bloodstream as it does in the mouse, so it’s not totally outlandish to imagine that we might someday pop pills to increase our circulating GDF11 to stay stronger, smarter and generally healthier as we age. And already, researchers are discussing the need to seek potential benefits for patients with Alzheimer’s and other degenerative diseases.

Upcoming papers in the journal Science found that when given GDF11, some older mice — the equivalent of roughly 70-year-old humans — became able to run as long and smell as well as young mice.

The Harvard press release quotes Doug Melton, chair of the university’s Department of Stem Cell and Regenerative Biology, as saying he couldn’t “recall a more exciting finding to come from stem cell science and clever experiments. This should give us all hope for a healthier future. We all wonder why we were stronger and mentally more agile when young, and these two unusually exciting papers actually point to a possible answer:  the higher levels of the protein GDF11 we have when young. There seems to be little question that, at least in animals, GDF11 has an amazing capacity to restore aging muscle and brain function.”

I spoke with Harvard stem cell biologist Amy Wagers, a leader in the GDF11 research, about what it means. Our conversation, edited:

I imagine our headline shouldn’t say ‘Fountain of Youth discovered.’ How do you prefer the effects of GDF11 to be described?

I like ‘healthy aging.’ It’s really important to say that we don’t have any idea whether GDF11 might affect lifespan at all, but it does seem to improve or enhance healthy function in multiple different tissues.

What’s our best understanding at this point of what GDF11 does biologically?

I would say our understanding is still in its infancy. What we know is that GDF11 is a protein that is produced and present in the bloodstream at high levels when you’re young and it goes away as you get older. When you add it back to older animals, there are beneficial effects on a number of different tissues.

At the organismal level, we know that it enhanced muscle repair capacity and skeletal muscle structure so that physical function is improved. We know that in the brain it increases the production of neural stem cells and functioning of the olfactory system. And we know in the heart it reverses cardiac hypertrophy. Continue reading

Stem Cell Advance: The Little Liver That Builds Itself

"Liver buds" grow in a petri dish. The proto-organs are about 5 mm wide, or half the height of a classic Lego block. (Courtesy of Takanori Takebe/Yokohama City University Graduate School of Medicine via NPR)

“Liver buds” grow in a petri dish. The proto-organs are about 5 mm wide, or half the height of a classic Lego block. (Courtesy of Takanori Takebe/Yokohama City University Graduate School of Medicine via NPR)

The journal Nature reports today that Japanese scientists used human stem cells to create “liver buds” — tiny precursors to full-fledged livers — that were then implanted into mice and functioned much like regular livers.

In other words, it appears that we’ve come our closest yet to actually building a solid-tissue human organ from stem cells. It will likely be a decade or more until this advance might help the many patients waiting desperately for transplants, but for now, stem cell experts say this is a significant breakthrough in regenerative medicine.

See the full NPR report on the experiment here, and the New York Times here. I spoke a bit earlier about the Nature report with Here & Now host Jeremy Hobson. Our conversation:

JH: So first of all, what did the researchers do here?

Well, what they did not do is use those politically controversial embryonic stem cells. These were what’s called “induced pluripotent stem cells,” they’re adult cells that have been kind of “reprogrammed” to be able to develop into various cell types.

What the researchers did was to mix together three types of human stem cells, and they found — to their own surprise, the first time they observed it — that the cells self-organized, or self-assembled, into a three-dimensional liver bud. A liver bud is normally found in an early embryo, and it later develops into a full-fledged liver. Continue reading

Harvard Biologist: When The Search For A Cure Gets Personal

Check out Rachel Gotbaum’s very nice profile of Doug Melton, Harvard’s influential stem cell scientist, on WBUR today.

Melton’s certainly had his share of media attention — he was at the center of the controversy over embryonic stem cell research, which anti-abortion activists tried to stop during the Bush administration. But Gotbaum’s story focuses on a more personal aspect of the biologist’s work: trying to find a cure for diseases like diabetes, which afflicts both of his children. Melton’s career trajectory underwent a radical shift shortly after he and his wife learned their infant son was sick:

Stem cell scientist Doug Melton began searching for a cure for diabetes  after his infant son was diagnosed with the disease. (Photo: Jesse Costa, WBUR)

Stem cell scientist Doug Melton began searching for a cure for diabetes after his infant son was diagnosed with the disease. (Photo: Jesse Costa, WBUR)

In 1981, Melton was recruited by Harvard, where he focused on molecular biology and embryology. But all that changed 10 years later when Melton’s infant son, Sam, became ill. His wife, Gail O’Keefe, says their son, who was 6 months old at the time, was not thriving.

“I started noticing that he wasn’t making any eye contact; something was clearly amiss but I couldn’t really put my finger on it,” O’Keefe said. “And then one morning he woke up and he was projectile vomiting.”

“We took him to the hospital and for a while no one could figure out what was wrong with him and it looked quite dire,” Melton recalled. “We now know that he was in extreme ketoacidosis, which is the stage before a person goes into a coma.”

The couple watched for hours as doctors at Boston Children’s Hospital tried to figure out what was wrong with Sam. Continue reading

Inside The Murky World Of Cosmetic Stem Cells

By Judy Foreman
Guest Contributor

The woman in L.A. simply wanted a facelift. That’s all. But what she got was a nightmare – and a lesson for any of us who might be lured into the under-studied territory of cosmetic stem cell procedures.

Several years ago, the woman went to a California clinic that offered her a cosmetic procedure in which her own adult stem cells were harvested from her abdominal fat. (Adult stem cells are undifferentiated cells found amidst differentiated cells in tissues throughout the body; these cells can not only make many endless copies of themselves, they can also differentiate to yield some or all of the major cell types of the tissue from which they came.

(thinkpanama/flickr)

(thinkpanama/flickr)


At the clinic, doctors extracted from the woman’s fat stem cells that could turn into bone, cartilage or fat, according to a recent Scientific American article. Apparently, these cells were either mixed with a facial “filler” called calcium hydroxylapatite or injected into the same area as the filler. The filler can nudge stem cells to turn into bone.

Three months later, the woman couldn’t open her right eye without significant discomfort, and she heard a strange, clicking sound every time she opened and closed her eye.

Worried, she sought help from a different clinic, The Morrow Institute in Rancho Mirage, and a different doctor, cosmetic surgeon Dr. Allan Wu, chief scientific officer of the institute’s stem cell research lab.

In a telephone interview this week, Wu told me that, during a multi-hour procedure, the Morrow team extracted bits of bone from her eyelid and the area around her eye. The clicking sound, he said, probably came from these bone fragments hitting each other. Though the woman, whose name has not been released publicly, appears to be fine now, he said, other facelifts using isolated and concentrated stem cells alone may carry a risk of unintended bone growth and other potential long-term consequences.

The operation “took all of us a lot of work, a lot of sweating,” Wu told me. “Why? Because when you see bone and fat, or if you happen to see hair [in parts of the body where they shouldn’t be] you worry about a teratoma [a kind of tumor] that stem cells can form. We were all very worried – the question was, was this cancer surgery or cosmetic reconstruction?” Continue reading

Scientific American: Brain Cells Made From Urine

mouse neurons

Mouse neurons (Wikimedia Commons)

Stem cells used to be big news, back when there was hot political controversy around using embryonic cells for potential disease cures. That heat has abated but among the quieter headlines about scientific progress on getting cells to do our bidding, this one in Scientific American is irresistible: Brain Cells Made From Urine.

And the sub-head: “Human excreta could be a powerful source of cells to study disease, bypassing some of the problems of using stem cells, such as the risk of developing tumors and difficulties in obtaining blood samples from children.”
The report begins:

Some of the waste that humans flush away every day could become a powerful source of brain cells to study disease, and may even one day be used in therapies for neurodegenerative diseases. Scientists have found a relatively straightforward way to persuade the cells discarded in human urine to turn into valuable neurons.

The technique, described online in a study in Nature Methods this week, does not involve embryonic stem cells. These come with serious drawbacks when transplanted, such as the risk of developing tumors. Instead, the method uses ordinary cells present in urine, and transforms them into neural progenitor cells — the precursors of brain cells. These precursor cells could help researchers to produce cells tailored to individuals more quickly and from more patients than current methods.

Read the full story here.

Harvard Researchers Report Faster, Better Technique For Stem Cell Production

Scientists report a more efficient method to produce stem cells

While a legal challenge to embryonic stem-cell use meanders through the court system, scientists at Harvard report a new and far more efficient technique to turn adult cells into stem cells, The Boston Globe reports.

The new technique, published in the journal Cell Stem Cell offers major improvements. The method does not involve dangerous genetic alterations, and is almost twice as fast and up to 100 times more efficient than the standard method used to turn cells back to an embryonic-like state. The induced pluripotent stem cells, or iPS cells, that are formed more closely resemble embryonic stem cells than those made using standard methods.

Still, The Globe quotes scientists saying that the new research doesn’t “negate the need for human embryonic stem cell research.” This week, a federal court lifted a ban on using federal funds for such research while an appeal is underway.

Daily Rounds: Fluoridation Resistance; Stem Cells On For Now; Phoning For Health Prices; ‘Emergency Bra’

Fluoridation is still a hard sell in Mass. – The Boston Globe “Nearly 150 cities and towns that could add the substance don’t, a state study released this year found — even though fluoridation is hailed by disease specialists as one of the 10 seminal public health triumphs of the past century.” (Boston Globe)

Stem cell research can continue throughout appeal, court says – latimes.com “Government-funded research on embryonic stem cells can continue, a U.S. appellate court said Tuesday, while lawyers appeal a judge’s decision that found such research illegal.” (Los Angeles Times)

Phone More Popular Than Internet When Seeking Prices For Health Care : Shots – Health News Blog : NPR “Three-quarters of those who investigated prices ahead of time said they found what they needed. How did they do it? Most used old-fashioned techniques: 61 percent got on the phone. 47 percent asked in person. 22 percent tried the Internet or e-mail. 12 percent cited mail. 4 percent found what they needed in magazines or books.” (npr.org)

‘Emergency Bra’ doubles as safe-breathing mask – BostonHerald.com “The bra cups are lined with air filters she said would protect the wearer from smoke, debris from explosions, dust storms, volcanic ash and radioactive or biological terrorist attacks. “It is an always available personal protection device, but first and foremost it is a beautiful piece of lingerie,” she told reporters, adding that it is not meant to replace military-issued gas masks.” (Boston Herald)

Collins, A Fervent Christian, At Center Of Stem-Cell Debate

Francis Collins, director of the NIH

There’s a great profile of Francis Collins — director of the National Institutes of Health and true-believing Christian in a sea of atheist scientists — in this week’s New Yorker. Writer Peter Boyer asks the question: How does a man who, while hiking, sees a frozen waterfall formed into three separate parts and takes it to be “a revelation of the Trinitarian truth,” also take on the role of chief cheerleader for embryonic stem-cell research?

The answer, it seems, is that while Collins is “personally torn by ethical questions posed by stem-cell research,” Boyer writes, he “also feels it is morally wasteful not to take advantage of the hundreds of thousands of embryos created for in-vitro fertilization that ultimately are disposed of anyway. These embryos are doomed, but they can help aid disease research.”

Daily Rounds: Stem Cell Appeal; A Plea For Primary Care; Grooving On The Treadmill

The Obama administration says it will appeal a court ruling that effectively shuts down embryonic stem cell research in the U.S. In the meantime, Monday’s temporary injunction issued by a federal judge will force the cancellation of dozens of research projects in areas ranging from diabetes to Parkinson’s disease, reports The New York Times.

Among the projects financed with this money is research by Dr. Doug Melton, co-director of the Harvard Stem Cell Institute, to find a cure for juvenile diabetes. His two children — a 19-year-old son and a 23-year-old daughter — have the disease. Both must inject themselves with insulin, and he said they frequently ask about his work.

Dr. Rob Lamberts, writing in The Health Care Blog, appeals to medical students considering a career in primary care. Compassion, patience and actually enjoying different kids of people (even the crazy ones) and their poignant imperfections are critical requirements of the job, he writes. Lamberts says the profession clearly needs replenishing, but, he adds: “I only want you in my field if you’d raise the average.”

Staying fit to a Latin beat. (AP)

Staying fit to a Latin beat. (AP)

And here’s something that anyone who endured one of those scary step aerobics classes in the 90s knew intuitively: the music matters. Gretchen Reynolds, in a post for The New York Times Well blog makes the case that listening to the kind of up-tempo, pulsing music they played in those step classes can substantially improve performance. She cites a study in which men pedaled stationary bikes and listened to music that was either slowed by 10 percent or sped up by the same amount. “The up-tempo music didn’t mask the discomfort of the exercise. But it seemed to motivate [the bikers] to push themselves. As the researchers wrote, when “the music was played faster, the participants chose to accept, and even prefer, a greater degree of effort.”

Opponent Of Embryonic Stem Cell Research Back In Spotlight

James Sherley

Photo/MIT

James Sherley

James Sherley has finally gotten his way.

Remember Sherley? He’s the former MIT associate professor who went on a hunger strike in 2007 because he was denied tenure — and claimed the decision was based on the fact that he’s black.

Well, Sherley is also an outspoken critic of embryonic stem cell research and opposes abortion, according to reports (he uses adult stem cells in his own research). And, as it turns out, he’s one of the remaining plaintiffs in the lawsuit that at least temporarily blocked President Obama’s executive order that allowed expanded embryonic stem cell research. Today’s ruling, which says that the president’s order violates a ban on using federal funds to destroy embryos, could render all embryonic stem cell research illegal, according to The New York Times.

Sherley, a biological engineer, now works at the Boston Biomedical Research Institute. I tried him by phone and email, but didn’t get a response.