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On Comparative Studies of Aging

Posted: June 11, 2010 at 8:14 am

Maria Konovalenko on the study of the often large life span differences between similar species – or rather the lack of such research work in comparison to other fields of life science: “Here’s this quite simple idea: to take two species similar in size and basic biology, but having a substantial difference in longevity, and figure out what’s the reason for this difference. What are the distinctions in the mechanisms of aging and stress resistance? It’s desirable to carry out this work in various species. However, not a lot of people are excited about this simple idea. Even the genome of the famous naked mole rat has not been sequenced yet, although many people believe it’s got ‘negligible’ senescence. For now all that we have is negligible funding of evolutionary-comparative biology of aging. Moreover, previously obtained results are put into cold storage. … And here comes the main question in biogerontology. Why is the research into the fundamental mechanisms of aging so scarcely funded?” Aging and longevity research in general receives very little funding and attention in comparison to its importance to the future of human health. This state of affairs is slowly changing, but not fast enough for my liking.

View the Article Under Discussion: http://maria-konovalenko.typepad.com/blog/2010/06/the-main-question-in-biogerontology.html

Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Recommendation and review posted by G. Smith

TOR and Calorie Restriction

Posted: June 11, 2010 at 8:14 am

Via Newswise: “Why all the attention on TOR? TOR (target of rapamycin) is a key nutrient-sensing catalytic enzyme that evolution has conserved among every plant and animal species that has cells containing a nucleus. TOR mediates the connection between nutrients in the environment to the growth and metabolism of the organism. Studies in flies, worms, yeast and mice support the notion that the TOR signaling network also plays a pivotal role in regulating the aging process. When TOR signaling is reduced, either through genetic manipulation or via the use of drugs, the organism presumes there are reduced nutrients in its environment and goes into a ’survival’ mode similar to that seen in dietary restriction, which has been shown to extend lifespan and slow the onset of certain age-related diseases. … it remains to be seen which downstream effectors of TOR are key drivers of longevity and which ones elicit only minor effects. In addition to simply extending lifespan, research on the protective effects of TOR is likely to identify which age-related diseases can be slowed by inhibition of the TOR pathway.”

View the Article Under Discussion: http://www.newswise.com/articles/tor-a-key-mediator-of-the-effects-of-dietary-restriction-and-its-impact-on-aging

Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Recommendation and review posted by G. Smith

A Report on the Fourth Asset Preservation Group Meeting

Posted: June 11, 2010 at 8:14 am

From Depressed Metabolism, a look at the folk who are trying to ensure that cryonics patients can preserve their resources as well as the fine structure of their brains: “On the weekend of April 23-25 I attended a meeting of the cryonics Asset Preservation Group held [near] Gloucester, Massachusetts. I will try to give a few brief summaries without going into detail about every presentation. … A central problem for cryonicists wanting revival trusts is that Cryopreserved Persons (CPs) are legally dead and are not ascertainable beneficiaries under trust law. My solution to this problem has been to have cryonics organizations (rather than the legal system) recognize the reanimated CP as the beneficiary. But finding the right cryonics organization to do this is not always easy. … the best presentation at this meeting of the Asset Preservation Group was the one on ‘Personal Revival Trusts’ by Igor Levenberg. I have been working with the thorny problems associated with cryonics reanimation trusts for years and I have never seen such careful and persuasive legal analyses.”

View the Article Under Discussion: http://www.depressedmetabolism.com/2010/06/02/fourth-asset-preservation-group-meeting/

Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Recommendation and review posted by G. Smith

Artificial Corneas

Posted: June 11, 2010 at 8:14 am

From Singularity Hub: “In order to work in the human body, an artificial cornea has to meet some rather stringent requirements. First, it has to bond to the human eye around its edge, but stay unclouded by cells in its center. To that end, [researchers] took a widely used opthalmological polymer (found often in intraocular lenses) and adapted it with other special polymers around the edges. Combined with the application of a growth factor protein, the modified edge promoted cell growth around the periphery of the implant and secured it in place using the body’s own cells. The center of the artificial cornea, however, does not promote cell growth and remains clear so that it can be seen through. The artificial cornea also has to move freely with the eyelid and balance moisture on its faces. The polymer [researchers] chose is hydrophobic, allowing tears to lubricate the surface and provide the correct moisture on both of its sides. … The artificial cornea has passed clinical trials and is ready to see expanded use in patients this year.”

View the Article Under Discussion: http://singularityhub.com/2010/06/02/germanys-artificial-cornea-getting-ready-to-restore-sight-to-thousands/

Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Recommendation and review posted by G. Smith

The Longevity Gene ‘Takeout’ in Flies

Posted: June 11, 2010 at 8:14 am

Researchers are turning up new longevity genes at a fair rate these days, and this latest discovery is illustrative of the methods used – start with what you know, and compare and contrast: “A major challenge in translating the positive effects of dietary restriction (DR) for the improvement of human health is the development of therapeutic mimics. One approach to finding DR mimics is based upon identification of the proximal effectors of DR life span extension. Whole genome profiling of DR in Drosophila shows a large number of changes in gene expression, making it difficult to establish which changes are involved in life span determination as opposed to other unrelated physiological changes. We used comparative whole genome expression profiling to discover genes whose change in expression is shared between DR and two molecular genetic life span extending interventions related to DR, increased dSir2 and decreased Dmp53 activity. We find twenty-one genes shared among the three related life span extending interventions. One of these genes, takeout, thought to be involved in circadian rhythms, feeding behavior and juvenile hormone binding is also increased in four other life span extending conditions: Rpd3, Indy, chico and methuselah. We demonstrate takeout is involved in longevity determination by specifically increasing adult takeout expression and extending life span. These studies demonstrate the power of comparative whole genome transcriptional profiling for identifying specific downstream elements of the DR life span extending pathway.”

View the Article Under Discussion: http://www.ncbi.nlm.nih.gov/pubmed/20519778

Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Recommendation and review posted by G. Smith

Learning from Werner Syndrome

Posted: June 11, 2010 at 8:14 am

Accelerated aging conditions may result from individual aspects of “normal” aging run wild and out of control. This means we can potentially learn more about those mechanisms. For example: “a gene shown to play a role in the aging process appears to play a role in the regulation of the differentiation of embryonic stem cells. … researchers identified a protein interaction that controls the silencing of Oct4, a key transcription factor that is critical to ensuring that embryonic stem cells remain pluripotent. The protein, WRNp, is the product of a gene associated with Werner syndrome, an autosomal recessive disorder hallmarked by premature aging. … We showed that the depletion of WRNp blocked the recruitment of Dnmt3b to the Oct4 promoter, and resulted in reduced methylation. The reduced DNA methylation was associated with continued Oct4 expression, which resulted in attenuated differentiation. … These results reveal a novel function of WRNp, and demonstrate that WRNp controls a key step in pluripotent stem cell differentiation. Our data support the emerging hypothesis that attenuated stem cell differentiation is involved in aging. This lack of differentiated cells may contribute to failure to maintain organ or tissue function in the later stages of life.”

View the Article Under Discussion: http://sify.com/news/aging-related-gene-plays-role-in-stem-cell-differentiation-news-international-kgfnOiabcdj.html

Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Recommendation and review posted by G. Smith


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