Longevity Meme News and Commentary

Ouroboros In Search Of Scientist Bloggers

Wed, 27 Aug 2008 13:35:46 CST

Chris Patil is in search of co-authors for the science of aging blog Ouroboros: "I originally conceived of Ouroboros as a community weblog for biogerontologists - which meant, primarily, that it would serve the community, but it was also my hope that others within the community would want to pitch in. So far so good on the primary mission, but I've been remiss in recruiting other biologists to contribute to the content on the web site. Furthermore, as I get busier and busier with science, it gets harder and harder to stay on top of the literature, and the primary mission sometimes suffers as well. So: Do you want to write for Ouroboros? The three main criteria are as follows: (a) Be a working scientist in a field relevant to the biology of aging. (b) Have strong English writing skills, and a perfectionist streak about your prose. (c) Be willing and able to commit to writing a ~500-word post based on a recent journal article about the biology of aging, around once a week. ... If youre not interested in writing but are still interested in pitching in, there's another job to be filled: 'beach-comber.' I follow the literature through a system of PubMed RSS feeds, but I dont scour the journals' tables of contents as thoroughly or rapidly as I'd like. So there's definitely room for a few folks to comb through the ToCs of journals as they're released."

View the Article Under Discussion: http://ouroboros.wordpress.com/2008/08/27/help-wanted/
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

An Interview With Doug Melton

Wed, 27 Aug 2008 13:23:26 CST

The Technology Review interviews researcher Doug Melton: "If a patient has Parkinson's disease, their dopamine-producing cells are gone. We don't understand anything about what makes those cells go away - the field is kind of stuck because you can't watch the progression of the disease. Stem cells can make neurons in a dish. Imagine you have iPS cells from a healthy person and from a Parkinson's patient. If you make dopamine neurons from both sets of cells in separate dishes, you can look at what went wrong with the diseased stem cell. The same approach will work with different degenerative diseases, such as diabetes or ALS. ... I think it will change the way degenerative diseases are studied - we'll reduce the whole process of disease to a petri dish. Within a few years, researchers the world over should have access to disease-specific cells that can be turned into cell types defective in a particular disease. ... Science clearly works best when you have a lot of bright, motivated people working on these problems. The institute has sent thousands of human embryonic stem-cell lines to hundreds of labs all over the world. We like to think that has been helpful in encouraging basic research on embryonic stem cells."

View the Article Under Discussion: http://www.technologyreview.com/printer_friendly_article.aspx?id=21307
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Microglia Versus Alzheimer's

Tue, 26 Aug 2008 14:49:58 CST

Researchers are attempting to convince the body's defences to attack the amyloid plaques of Alzheimer's disease (AD): "by stimulating a brain cell called a microglia the cells will partially engulf the senile plaques ... [this is] the first time that this phenomenon, believed to take place in living brain, has been duplicated in the laboratory. ... the plaques themselves are not sufficient microglial activators. But when the microglia were treated with inflammatory stimulants, they attacked the plaques. ... In AD patients, microglia are not coping with the plaque build-up. Therefore plaques accumulate faster than the microglia can digest them. If we can enhance microglial digestion of these plaques, we will have a fighting chance to eliminate AD ... The next step is to find a therapeutic drug that will stimulate the microglia to devour the plaques." Time will tell whether new methods of removing amyloid prove to be as futile as the one method demonstrated to date.

View the Article Under Discussion: http://www.sciencedaily.com/releases/2008/08/080825194705.htm
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Further Explorations in Calorie Restriction

Tue, 26 Aug 2008 14:31:14 CST

Via Science News, something for those of us interested in the biochemistry of calorie restriction: "Less food doesn't always mean less energy. Restricting the diet of yeast cells makes them live about 30 percent longer than normal, scientists have known. But new research shows that these calorie-restricted cells make just as much ATP - the energy currency of cells - as do yeast cells fed a normal diet. The cells have just as much energy available, so [it's] not a starvation; it's just a specific sort of remodeling of the cells' metabolism in a way that also causes the organism to live longer ... the cells cut back on making lipids and instead rerouted energy to making ATP ... Normally, lipid molecules such as free fatty acids accumulate in yeast cells. This impairs the cells and can even cause them to self-destruct. So diverting energy away from making these lipids could help explain why calorie restriction prolongs the cells' lifespan. ... that some of the changes in the cells stimulate mitochondria, the 'power plants' of cells. As a consequence, these mitochondria churn out free radicals such as hydrogen peroxide at doses too low to do much damage to the cells but high enough to activate the cells' stress-response proteins. These groups of proteins go around fixing damage in the cells, a kind of house cleaning that can also help the cells live longer."

View the Article Under Discussion: http://www.sciencenews.org/view/generic/id/35835/title/Live_long_and_alter
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Defining Pluripotency

Mon, 25 Aug 2008 13:29:32 CST

You have to keep an eye on what's going on in infrastructural science. It's the improvements in cost, accuracy, and efficiency - that tend not to get as much press - that create an environment in which real breakthroughs can happen. Take this for example, via GEN News: "An international team of investigators determined that pluripotent stem cell lines display significant chemical similarity. The cell samples used in the study all had a particular protein-protein network in common. ... the profiles uniquely characteristic of the pluripotent populations, whether they came from embryonic stem cells or induced pluripotent cells. The researchers also found these profiles were shared by mouse embryonic stem cells, induced mouse pluripotent stem cells, and human oocytes. Detailed analysis showed that the interacting protein elements can be used to predict whether genetically induced stem cells will be pluripotent." Standardization is another thing to watch for - it will certainly speed things up.

View the Article Under Discussion: http://www.genengnews.com/news/bnitem.aspx?name=40923389
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

The Bad Trends

Mon, 25 Aug 2008 13:11:13 CST

There are plenty of good trends in medicine research and development. The trend in bioinformatics and computational power, for example. Unfortunately, some of the bad trends are blocking movement of research into the clinic. Via FuturePundit: "Why do terminally ill patients have to wait so long to get access to the only treatments that hold any promise of saving their lives? And why is it not their right to decide? ... The FDA approved just 16 new drugs last year, and is on pace to approve only 18 this year. That's down from a high of 53 in 1996 and 39 in 1997. ... This trend does not bode well for the development of rejuvenation therapies. The FDA will hold off approval of an anti-cancer drug for people who have a fatal disease. Never mind that people who have a fatal disease are going to die anyway. The FDA won't let people take a risk when they have little to lose. That makes no sense to me. Rejuvenation therapies are going to treat that fatal disease called aging. Absent those therapies we are all going to die from complications of aging. ... Faced with rising risks of death combined with increasing pain and disablement people should be given wider latitude to try new and unproven therapies." The FDA should torn down completely; it is a roadblock to progress, and the cause of great and ongoing suffering.

View the Article Under Discussion: http://www.futurepundit.com/archives/005479.html
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

More Compelling Reasons To Exercise

Fri, 22 Aug 2008 14:11:49 CST

Here is another study to add to the huge stack of research telling us that exercise is good for healthy longevity: "We determined whether reduced insulin sensitivity, mitochondrial dysfunction and other age-related dysfunctions are inevitable consequences of aging or secondary to physical inactivity. ... Insulin-induced glucose disposal and suppression of endogenous glucose production were higher in the trained young and older people but no age-effect was noted. Age-related decline in mitochondrial oxidative capacity was absent in endurance-trained individuals. Although endurance trained individuals exhibited higher expression of mitochondrial proteins, mtDNA, and mitochondrial transcription factors there were persisting effects of age. SIRT3 expression was lower with age in sedentary but equally elevated in endurance trained individuals. ... The results demonstrate that reduced insulin sensitivity is likely related to changes in [level of body fat] and physical inactivity rather than an inevitable consequence of aging. The results also show that regular endurance exercise partly normalizes age-related mitochondrial dysfunction, although there are persisting effects of age at the level of mtDNA abundance, nuclear transcription factors, and mitochondrial protein expression. Furthermore, exercise may promote longevity through pathways common to effects of caloric restriction."

View the Article Under Discussion: http://pmid.us/18716044
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Ouroboros On Biomarkers and Telomere Length

Fri, 22 Aug 2008 13:31:49 CST

From Ouroboros: "How old are you? At present, the best experimental approach to that question is to inspect your driver's license; we are very good at measuring chronological age, but far worse at measuring physiological age. ... Until we have such a tool, questions like 'how rapidly is this individual aging?' and 'is this treatment having a positive effect on the rate of aging? will be meaningless. ... So, the race is on to find useful biomarkers of aging. ... Telomere length is a tantalizing biomarker for the aging process: it's positively correlated with life expectancy and negatively correlated with stress and disease. If telomere shortening is a biomarker of aging, then the measurable consequences of telomere shortening should also function as biomarkers, i.e., aging bodies should contain high levels of factors secreted by cells with dysfunctional or critically short telomeres. According to a recent paper by Jiang et al., this is indeed the case. ... The proteins identified here accumulate with age - [and] they accumulate faster in subjects who are both aged and suffering from age-related disease; in other words, in people whom we might intuitively assign to the 'more rapidly aging' category."

View the Article Under Discussion: http://ouroboros.wordpress.com/2008/08/21/telomere-dysfunction-markers-as-biomarkers-of-aging/
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Weight Gain Cast as a Result of Neural Damage

Thu, 21 Aug 2008 14:52:24 CST

Hopefully you don't need more reasons to eat a sensible diet by now, but here's another. EurekAlert! passes on a theory to account for what happens to those of us who load up the carbohydrates over the years: "key appetite control cells in the human brain degenerate over time, causing increased hunger and potentially weight-gain as we grow older ... appetite-suppressing cells are attacked by free radicals after eating and [the] degeneration is more significant following meals rich in carbohydrates and sugars ... People in the age group of 25 to 50 are most at risk. The neurons that tell people in the crucial age range not to over-eat are being killed-off. ... When the stomach is empty, it triggers the ghrelin hormone that notifies the brain that we are hungry. When we are full, a set of neurons known as POMCs kick in. ... However, free radicals created naturally in the body attack the POMC neurons. This process causes the neurons to degenerate over time, affecting our judgement as to when our hunger is satisfied ... The free radicals also try to attack the hunger neurons, but these are protected by the uncoupling protein 2 (UCP2)." So eat more over the years and suffer neural damage that makes it harder not to eat more. We all have free will, but why make it harder for yourself?

View the Article Under Discussion: http://www.eurekalert.org/pub_releases/2008-08/mu-kc082108.php
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Michael Rae On Repairing Liver Aging

Thu, 21 Aug 2008 14:39:52 CST

Over at the Methuselah Foundation forums Michael Rae adds a lot more detail to news of lysosomal manipulations that halt liver aging in mice: "I think that we should regard this [as] supportive evidence for LysoSENS, rather than as an intervention that we should seek to translate for human use. I don't want to give the impression that this is anything less than an amazing result - I'm very impressed with the work itself, and excited by the actual effects on the animals --however, I think it's important to also see how [even] this sweeping result still suffers the standard flaws in the 'gerontological' approach to anti-aging medicine. ... note that in order to get the full effects of the intervention, the transgene had to be activated when the animals were 6 mo old - quite young ... because such 'gerontological' interventions slow down, but cannot reverse, the accumulation of aging damage, they are necessarily less effective the older people get. [This is] both because of their progressive rise in pre-existing aging damage, and the impairments in ability to adapt to and exploit such improvements due to other, independently-acting aging processes, making it hard to really benefit people who (as Dr. de Grey often puts it) 'have the misfortune to be already alive' - and especially people who are significantly older, in whom the need is greatest." You'll also find a detailed discussion of the science to back up those points.

View the Article Under Discussion: http://www.mfoundation.org/forums/showthread.php?p=4153#post4153
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Menstrual Blood as Source of Adult Stem Cells

Wed, 20 Aug 2008 13:47:41 CST

Like heart damage, peripheral artery disease is open to comparatively simple stem cell therapies based on cell transplants. All that is needed is a low-cost source of suitable stem cells. From ScienceDaily: "Cells obtained from menstrual blood, termed 'endometrial regenerative cells' (ERCs) are capable of restoring blood flow in an animal model of advanced peripheral artery disease. A new study demonstrates that when circulation-blocked mice were treated with ERC injections, circulation and functionality were restored. ... [Researchers have] already performed clinical trials with adult stem cells for patients with peripheral artery disease. .... The advantage of ERCs is that they can be used in an 'off the shelf' manner, meaning they can be delivered to the point of care, do not require matching, and are easily injectable without the need for complex equipment." The ease with which a therapy can be implemented makes a great deal of difference to the speed with which it moves from laboratory to clinic.

View the Article Under Discussion: http://www.sciencedaily.com/releases/2008/08/080818220609.htm
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Building Blood From Stem Cells

Wed, 20 Aug 2008 13:36:11 CST

The Times has more on growing blood from stem cells: "Vials of human blood have been grown from embryonic stem cells for the first time during research that promises to provide an almost limitless supply suitable for transfusion into any patient. The achievement by scientists in the United States could lead to trials of the blood within two years, and ultimately to an alternative to donations that would transform medicine. If such blood was made from stem cells of the O negative blood type, which is compatible with every blood group but is often in short supply, it could be given safely to anybody who needs a transfusion. ... One of the biggest safety hurdles that must be cleared before stem-cell therapies enter clinical trials is the risk of uncontrolled cell growth causing cancer. Red blood cells, however, do not have nuclei that carry the genetic material that goes wrong in cancer, and thus should not present this danger. ... While a few red blood cells have been created from embryonic stem cells before, the ACT team is the first to mass-produce them on the scale required for medical use. They also showed that the red cells were capable of carrying oxygen, and that they responded to biological cues in similar fashion to the real thing."

View the Article Under Discussion: http://www.timesonline.co.uk/tol/life_and_style/health/article4567387.ece
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

A Profile of Robert Lanza

Tue, 19 Aug 2008 12:55:36 CST

Discover Magazine looks at one of the noteworthies of the stem cell research community: "The value of therapeutic cloning has long been clear to Lanza, who did his early work with South African heart transplant pioneer Christiaan Barnard. Starting from those early days, Lanza understood that the barrier to tissue transfer was rejection by the recipient. From an entire organ to a dose of embryonic stem cells, if the tissue's DNA came from anyone else, the transplant would be rejected without the aid of harsh immunosuppressive drugs. 'The treatment could be worse than the problem,' Lanza found. But embryonic clones, the source of an endless supply of stem cells imprinted with one's personal DNA, could alter the equation in favor of the patient and augur a paradigm shift in medicine on par with the changes brought about by antibiotics and vaccines ... With the ability to become all of the blood cells - including your immune cells, red blood cells, all of your blood system, as well as vasculature, [hemangioblasts] have been biology's holy grail. What we discovered is that we can create literally millions or billions of these from human embryonic stem cells. ... we can use transient, intermediate cells like hemangioblasts as a toolbox to fix the adult so you don't have to have limbs amputated, so you may not have to go blind, to prevent heart attacks."

View the Article Under Discussion: http://discovermagazine.com/2008/sep/19-fighting-for-the-right-to-clone/article_print
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

On Salamanders and Limb Regeneration

Tue, 19 Aug 2008 09:43:10 CST

From the Technology Review: "While all animals can regenerate tissue to a certain extent - we can grow muscle, bone, and nerves, for example - salamanders and newts are the only vertebrates that can grow entire organs and replacement limbs as adults. When a leg is lost to injury, cells near the wound begin to dedifferentiate, losing the specialized characteristics that made them a muscle cell or bone cell. These cells then replicate and form a limb bud, or blastema, which goes on to grow a limb the same way that it forms during normal development. Scientists have identified some of the molecular signals that play a key role in the process, but the genetic blueprint that underlies regeneration remains unknown. Researchers hope that by uncovering these molecular tricks, they can ultimately apply them to humans to regrow damaged heart or brain tissue, and maybe even grow new limbs. ... One of the key questions yet to be answered is whether the salamander has unique genetic properties that enable regeneration, or whether all animals have that innate capability. ... If we come up with some totally unique gene only present in [salamanders], that would make it really hard to replicate."

View the Article Under Discussion: http://www.technologyreview.com/printer_friendly_article.aspx?id=21265
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Laron Dwarfism, Longevity, and Cancer

Mon, 18 Aug 2008 13:51:03 CST

At first glance, Laron dwarfs appear to be the Ames dwarf mice of the human world - long-lived and resistant to cancer, due to a genetic mutation that suppresses the somatotrophe axis: "There are a little more than 300 people in the world with the condition Laron dwarfism, a third of whom live in remote villages in Ecuador's southern Loja province. Sufferers of Laron - believed to be caused by inbreeding - lack a hormone called Insulin-like Growth Factor 1, or IGF1. Research [suggests] this is the reason for their longevity and apparent immunity to cancer. ... We've discovered that people with Laron simply don't get cancer. Cancer can be detected in their relatives of a normal size, but never in my patients - not one single case. ... Laboratory work in mice, flies and worms has shown that if IGF1 is removed, the animals tend not to get cancer and to live longer. This is now mirrored in recent research into small humans, who turn out to have little or no IGF1." There are a few large factual mistakes in the article, as might be expected given the source, but it is most interesting to see this work in mice translate so faithfully to humans.

View the Article Under Discussion: http://www.dailymail.co.uk/news/worldnews/article-1045987/Immune-cancer-The-astonishing-dwarf-community-Ecuador-hold-key-cure.html
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/