Showing posts with label Regeneration. Show all posts
Showing posts with label Regeneration. Show all posts

Tuesday, November 30, 2010

Reversing Aging

Harvard team successfully reverses the aging process in mice

By Loz Blain

23:04 November 29, 2010

Chromosomes, with their telomere caps highlighted. Looking after these telomeres could be ...

Chromosomes, with their telomere caps highlighted. Looking after these telomeres could be the key to longer life.

The aging process - it's undignified, unwanted, and many would say unnecessary. After all, the cells in your body are constantly replacing themselves – why can't they do it without causing progressive degradation of organs that lead to discomfort, weakness and death? Well, perhaps they can. Harvard scientists have discovered that by controlling certain genetic processes in mice, they can not only slow down the aging process, but "dramatically" reverse it throughout the body. It's a massive discovery, but it won't be able to be used in humans yet without some pretty scary consequences.

Telomeres

The Harvard study focused on part of the cell division process called 'telomere shortening.' If you picture a chromosome as an X-shaped unit of DNA, the telomeres are the little caps at the end of each strand.

As cells divide, their DNA splits in half to form two new cells – but a bit of genetic information is lost at the end of each strand with each division. That's what telomeres are for – they contain a bunch of useless DNA that acts as a buffer zone so that no important DNA is lost from our chromosomes. Gradually, over time, the telomere erodes away to a level where each cell division actually starts destroying bits of important DNA – and this gets to a point where the cell can no longer reproduce itself. You can imagine what that starts doing to bodily organs as time goes by.

So in a way, telomeres are there as a built-in limit to how many times a cell can divide itself – they're part of the built-in biological clock that causes aging, body deterioration and death.

The Harvard Study

And that's where this recent study was focused. Ronald DePinho and a team of Harvard colleagues experimented on mice to see what happens when steps are taken to stop telomeres from shortening.

The group looked at the enzyme telomerase, which can replenish the telomere after replication and effectively lengthen it so that a cell can live for longer.

They bred a group of genetically-engineered mice that lacked the ability to produce telomerase – and watched as these mice showed rapid and very early onset symptoms of aging.

Then, they gave the mice injections to re-activate the telomerase enzyme – expecting to see the aging process slow down to normal levels. Instead, they watched in astonishment as the mice appeared to age backwards, their withered organs repairing themselves even to the point of new neurons beginning to sprout in their brains.

In essence, repairing the telomeres seemed to be able to reverse the aging process and make the mice physiologically younger, despite already suffering the ravages of age.

But it's not so simple for humans

While this study was a huge step forward in our understanding of how telomeres and telomerase impact the aging process, there's a big issue preventing this sort of treatment from going straight into human testing.

Mice produce telomerase all throughout their short lives, but the enzyme is switched off in adult humans with our longer life spans, because when our cells are allowed to divide and replicate unchecked, they have a nasty habit of developing into cancers.

Although a telomerase-activating compound was recently discovered, telomerase rejuvenation in adults is directly linked to the development and spread of cancers throughout the body – so while a telomerase-based anti-aging treatment might produce valuable results in older humans, scientists also believe it would kick the risk of cancer up several orders of magnitude.

So the study isn't the sort of breakthrough that will lead directly and immediately to any sort of treatment for humans – but it's another step forward in science's inevitable march towards human immortality. Imagine what a gift it would be for an 80-year-old to be given an injection that could tell the cells in his body to rebuild itself in the physical health he enjoyed as a 25-year-old, knowing everything he knows.

There are already debates flaring over the ethics of extending lifespan, and the question of whether humans should submit themselves to the long-accepted ravages of aging and death or use our amazing command of science to avoid them. But the fact is, we're going to work out how to do it sooner or later, whether or not it involves this sort of telomere repair process, and a significant number of people will want to use such a technology to repair their bodies and see what life is like in the next few centuries.

Would you be one of them?

Monday, November 22, 2010

Reasons Why We Will Eventually Reverse Aging - Aubrey de Grey

One day, our species may look back at these times and gasp at how we once aged and slowly died.



Excerpt from the following: http://www.slate.com/id/2274582/pagenum/all/

The classical areas of regenerative medicine have been moving ahead at an unprecedented pace in recent years. Some of the highlights have, with good reason, been celebrated in the mainstream media: The foremost example is the development by Shinya Yamanaka, and subsequent refinement by numerous groups, of a method to convert adult cells into a state very similar to embryonic stem cells. These cells, termed "induced pluripotent stem cells" or iPS cells, appear to have almost all the versatility of true embryonic stem cells, but can be obtained far more easily, in far greater numbers, and without the main ethical challenges that have confronted the embryonic stem cell field. Stem Cells

Less celebrated, but possibly of similar significance, is an advance in tissue engineering. Following the pioneering work of Doris Taylor, many groups are now pursuing a creative solution to the main problem that has always dogged tissue engineering: vascularization. The blood supply is a vital component of any solid organ, and it has proved hugely difficult to cajole the body to create a competent vasculature in an artificial organ before the cells in that organ have succumbed to deprivation of oxygen or nutrients. Taylor's solution is to "decellularize" an organ from another individual—possibly not even from a human—leaving only the extracellular matrix that defines the vasculature, and then to repopulate this scaffold with suitable cells typically taken from the intended recipient of the organ. This achieves the main goal of tissue engineering, the rejection-free replacement of a damaged organ. Replacing Damaged Organs

Less conspicuous is "molecular regenerative medicine"— repair of the intracellular structure of live cells in situ, or of extracellular structures, as opposed to the wholesale replacement of cells or organs. One of the most impressive advances within this field relates to Alzheimer's disease.The amyloid plaques that accumulate in the brains of Alzheimer's sufferers can be removed by vaccination, a trick that was first demonstrated (in mice) a decade ago. Doubts surfaced thereafter concerning whether this could work in humans, but the approach looks promising at present, with clinical trials having progressed to Phase III. Removal of plaques is unlikely to constitute a complete cure for Alzheimer's disease, but it is almost certain to be part of an eventual combination treatment.Removing Dead and Diseased Cells

At an earlier stage, but still immensely exciting, is the corresponding treatment for "molecular garbage" that accumulates not between cells but inside them. This is a more challenging aspect of aging, because the material in question is resistant to breakdown by any human enzymes. The solution being pursued by the SENS Foundation, the charity of which I am the chief science officer (SENS stands for Strategies for Engineered Negligible Senescence), is to identify non-human enzymes that can do the job and introduce them into our cells. The biggest initial challenge is to identify such enzymes, but we have now done that with respect to the main types of garbage responsible for cardiovascular disease and macular degeneration. This has already led to several peer-reviewed academic publications, and we hope to bring it to the stage of testing in mice within the near future. Eliminating Molecular Garbage

Additional targets being pursued by SENS Foundation include the elimination of cells that refuse to die when the body wants them to—a major aspect of the decline of the immune system with age, among other things—and the prevention of mitochondrial mutations by putting modified copies of the mitochondrial DNA into the nucleus. These projects are moving forward with impressive speed, though slowed by resource limitations.

When all these components are combined, will we have bona fide rejuvenation biotech? We won't know that for certain until we complete the development of all those components, at least in mice. But every type of "aging damage" of which we're aware—and for which SENS Foundation and others are developing interventions—has been known about for well over a quarter of a century. If some other factor is at work in aging, then biologists should have identified it by now. It looks as though all that stands between us and control of aging is hard work. Let's up the pace.

Friday, October 22, 2010

Regenerating body parts

Woman's persistence pays off in regenerated fingertip

By Elizabeth Cohen, CNN Senior Medical Correspondent
September 9, 2010 -- Updated 2051 GMT (0451 HKT)
When the slam of a door chopped off the tip of her pinky, doctors told Deepa Kulkarni nothing could be done. She did her own research and proved them wrong.
When the slam of a door chopped off the tip of her pinky, doctors told Deepa Kulkarni nothing could be done. She did her own research and proved them wrong.
STORY HIGHLIGHTS
  • Sometimes doctors don't know about new treatments being used by other physicians
  • Don't hesitate to e-mail a doctor who's a leader in the field that could help you
  • That treatment that looks perfect on the internet might work for you -- but it might not

(CNN) -- After running inside from a rainstorm one Friday evening last January, Deepa Kulkarni leaned against the doorway with her right hand to take off her boots. Then, in an effort to make sure the dog didn't get out, someone slammed the door hard, and it landed right on her pinky.

Kulkarni thought the door had only bruised her finger, but then she looked down and saw the tip of her pinky lying on the floor.

"I swooped down and picked it up before the dog got it," she remembers. "At first I was fine, but then I saw the blood -- there was so much blood -- and I felt woozy."

Her husband, Ajit, called an ambulance, and as soon as his parents arrived to take care of their two young children, Kulkarni retrieved her pinky tip from the freezer -- it had broken off just above the base of her fingernail -- and they headed from their home in Davis, California, to the emergency room.

Video: Woman grows back finger tip

That trip to the hospital was the beginning of a five-week odyssey -- one that involved defying doctors, e-mailing specialists around the country and -- in her words -- being pushy and demanding in order to make her pinky whole again.

'100 percent chance of failure'

"The doctor who was on call at the emergency room told me there was no way he could reattach my pinky," she says. "I didn't like that, so I asked to see a specialist."

An orthopedic surgeon concurred with the ER doctor, and made an additional recommendation: He'd have to amputate even more of the finger so it would heal properly.

"I was like, no way, with so much technology out there, there must be some other way to do this," she said. "But he said he wouldn't even attempt to reattach it. He said was there was a 100 percent chance of failure," she remembers.

Disappointed but defiant, Kulkarni declined the surgeon's treatment, and the doctors sent her home with a bandaged finger and painkillers.

'I am writing to you out of desperation.'

Deepa Kulkarni displays her hand after the accident.
Deepa Kulkarni displays her hand after the accident.

Arriving home at midnight, Kulkarni fell asleep, and the next morning immediately got on her computer. With her nine functioning fingers she searched for hope -- any hope -- that her pinky could be repaired.

Kulkarni, a former human resources manager who is now in law school full time, was accustomed to doing research, but after searching for hours, she still couldn't find any new ideas for reattachment.

Kulkarni's pinky grew back after she persuaded a doctor to administer a procedure she had read about on the internet.
Kulkarni's pinky grew back after she persuaded a doctor to administer a procedure she had read about on the internet.

She did, however, find something else: stories on "60 Minutes" and "Oprah" about a relatively new procedure called tissue regeneration, which had made amputated finger parts grow back for other patients.

She went to the website for Dr. Stephen Badylak, the University of Pittsburgh physician who helped pioneer the procedure. A little more searching revealed his e-mail address.

Kulkarni displays her new pinky next to the tip of her old pinky.
Kulkarni displays her new pinky next to the tip of her old pinky.

"Dear Dr. Badylak," she began. "I am writing to you out of desperation...I ran across your article on the internet and decided to write to you. Can you tell me if [tissue regeneration] works and what my options are to get the treatment?"

She heard back the next day, a Sunday, from one of Dr. Badylak's colleagues. He gave her more details about the procedure, and some bad news: He didn't know of any doctors near her using regenerative medicine.

She e-mailed him photos of her damaged pinky, and he said the team of doctors in Pittsburgh would review them and decide whether they could help her. In the meantime, Kulkarni sent out an all-call in search of a physician near them who used tissue regeneration.

"I e-mailed people at UCLA and Berkeley, and my husband and I called everyone we knew who was a doctor or might know a doctor," she says.

Still, no one had any ideas for her. One friend introduced her to Dr. Malathi Srinivasan, an internist at the University of California-Davis Medical Center, who called Kulkarni from her cell phone while driving home from a skiing trip at Lake Tahoe.

Srinivasan didn't know any doctors with experience in tissue regeneration, but she did give her something Kulkarni badly needed at this point: hope.

"I encouraged her to keep looking, and I did some PubMed searches myself," Srinivasan says, referring to the National Library of Medicine's online collection of research materials.

Seven weeks later, a new pinky

Eventually, Kulkarni made an appointment with Dr. Michael Peterson, an orthopedic surgeon in Davis. At first, Kulkarni says he was hesitant to try tissue regeneration since he hadn't done it before, but she gave him some research materials, and she says eventually he agreed to try it.

The therapy involved cleaning out the finger and removing scar tissue -- a process called debridement -- and then dipping her finger into MatriStem wound powder. After seven weeks of treatment, her fingertip grew back (as shown in the before and after photos above).

"Even now it's not perfect. It's shorter than the other pinky, but just by looking at it you can't tell it was an amputated finger," she says. "I'm able to do everything I could do before. I wash dishes. I cook," she says, adding that she's had physical therapy to decrease tingling in her finger caused by severed nerves.

Kulkarni still keeps her severed pinky tip in the freezer. She thawed it out so CNN could take a photograph of the pinky tip alongside her regenerated finger.

Five lessons learned

Here are lessons Kulkarni learned through her pinky ordeal, plus a few from the doctors who worked with her:

1. Realize your doctor doesn't know everything

"I grew up in India, and doctors there were looked up to as being next to God, and they knew everything and could cure you," Kulkarni says. "What I found out is that even though I like my doctors, I don't have to take every recommendation they give me. I can do my own research."

Srinivasan, the physician who encouraged Kulkarni not to give up, says sometimes doctors don't know about new, cutting-edge treatments being used by other physicians.

"Some doctors are more out-of-date or up-to-date than others," says Srinivasan, an associate professor of medicine at UC-Davis Medical Center who does research on shared decision-making between doctors and patients.

Kulkarni said even when her prospects looked dim, she never completely gave up hope.

"My husband and I are quite pushy, and my husband is smart -- he has a Ph.D. in electrical engineering. We weren't going to take no for an answer," she says.

Petersen, Kulkarni's surgeon, says he's learned from many patients who've come to him having done research on the internet.

"I get a lot of good ideas from patients," he says. "One of the things we have to do as physicians is to listen to our patients."

2. E-mail doctors you don't know

Even though you're a stranger, if you write to a doctor who's a leader in the field, you might get an e-mail in return.

"The doctor from Pittsburgh wrote me back the very next day, on a Sunday," Kulkarni says. "I was so surprised. Maybe I sounded really desperate."

Even if you can't afford to fly out to the expert for treatment, he or she might be able to lead you to a local doctor who can help.

3. Don't be afraid to be a 'bad' patient

Kulkarni said she knows the doctors she saw in the emergency room might have perceived her as an annoying patient when she rejected their treatment options.

"I didn't care," she says. "Imagine if I hadn't pursued other options because I was worried about what other people think -- I didn't want to live with that regret."

4. Be organized

Be fastidious about keeping records. Kulkarni, for example, photographed her pinky at various stages, and she e-mailed the images to various doctors and later to the insurance company to convince them to reimburse her the $1,665 she spent on the drug that regenerated her pinky.

5. Recognize you might be wrong

That treatment that looks perfect on the internet might work for you -- but it might not.

"Sometimes patients are pretty certain through their own research what their problem is and what they need," says Petersen. "It's not up to us as doctors to agree with them. Sometimes part of my role is to guide them that, in reality, that isn't your problem and I don't recommend that treatment."

Learn more about Elizabeth Cohen's book on being an Empowered Patient. Video

CNN's Sabriya Rice contributed to this report.

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