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corybroo

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  1. Medical Xpress has a nice review of theories of aging: https://medicalxpress.com/news/2019-10-age-theories-gaining-ground.html Spoiler alert: The article leans toward hyperfunction of TOR.
  2. Medical Xpress has an article Cellular aging is linked to structural changes in the brain https://medicalxpress.com/news/2019-09-cellular-aging-linked-brain.html Telomere length is therefore regarded as a marker for the biological age … person with shorter telomeres has an increased risk of developing age-related diseases such as Alzheimer's or cancer, and even a shorter life expectancy. Recent studies suggest that telomeres can change faster than previously thought, possibly taking just one to six months of mental or physical training to elongate. "To explore whether a short-term change in telomere length, after only a few months, might actually be associated with changes in a person's biological age, we linked it to another biomarker of aging and health: brain structure," Four MRIs and blood draws for leukocyte DNA three months apart If the telomeres changed in length, this was associated with structural changes in the brain. In a period when participants' telomeres lengthened during the study, it was also more likely that their cortex had thickened at the same time. On the other hand, telomere shortening was associated with reductions of gray matter. This association occurred specifically in a brain region called the precuneus, which is a central metabolic and connectional hub. Open questions: it remains unclear if telomere elongation actually reflects any improvement in a person's overall health and aging trajectory. Future studies will need to continue to address the question of which measures or behaviors most effectively stop or even reverse telomere shortening, and the biological aging process.
  3. corybroo

    Blog post for a non-CR audience

    A nice introduction to the variables we can control to best play the genetic hand we've been dealt. To the benefits of exercise, you may want to add the possible modification of telomere length. Do a google search for HIIT telomere length https://www.researchgate.net/publication/325134827_The_effect_of_high_intensity_interval_training_on_telomere_length_and_telomerase_activity_in_non-athlete_young_men Conclusion: It seems that HIIT can alter telomerase activity and telomere length. Therefore, these training may have a positive effect on cell biology. To the section on IF, you may want to add something about preservation vs repair mode in different states. And possibly, as inspiration for others, how you're choosing to bring all this together for your self. As much as anything, that's to avoid the old cartoon of an overweight doctor telling his patient to lose weight. HTH, Cory
  4. https://medicalxpress.com/news/2019-08-memory-cells-bone-marrow-boosting.html Memory T cells shelter in bone marrow, boosting immunity in mice with restricted diets Discusses how immunity is maintained while calories are restricted. "... previously observed that fat tissue harbors memory T cells in mice. They investigated whether this phenomenon helped preserve immune memory when calorie intake was reduced. To investigate, they restricted the diet of mice previously given full access to food. While receiving less food, mice had fewer memory T cells in their lymphoid tissues, where they normally linger, and more of the T cells in bone marrow that became enriched with fat tissue." "Mice with restricted diets had more robust memory T cell responses and were better protected from illness. The researchers repeated this experiment using a vaccine that trains immune cells to fight melanomas and found that memory T cells were more protective against tumors in mice receiving less food."
  5. A moderate dose of novel form of stress promotes longevity https://medicalxpress.com/news/2019-07-moderate-dose-stress-longevity.html moderate chromatin stress levels set off a stress response in yeast, the tiny laboratory worm C. elegans, the fruit fly and mouse embryonic stem cells, and in yeast and C. elegans the response promotes longevity. "Unexpectedly, we found that yeast with fewer copies of histone genes lived longer than the controls," Yeast with a moderately low dose of histone genes showed a moderate reduction of histone gene expression and significant chromatin stress. Their response to chromatin disruption was changes in the activation of a number of genes that eventually promoted longevity. In previous work Dang and colleagues had shown that in aging cells chromatin structure progressively falls apart. Histone alterations, such as a decrease in their protein levels, are a characteristic of the aging process, but the researchers showed that if they compensated for this age-related decrease in histone levels by overexpressing certain histone genes they extended the lifespan of aging yeast cells. In this study they discovered that moderately reducing the number of copies of histone genes in young yeast also promoted longevity. "The mechanism underlying the chromatin stress response generated by moderate reduction of histone dosage is different from the one triggered by histone overexpression we had previously described, as shown by their different profiles of protein expression responses."
  6. Medical Express has an article about a recently found link between amyloid and tau leading to Alzheimer's https://medicalxpress.com/news/2019-06-alzheimer-link-idd-brain-decline.html Alzheimer's missing link ID'd, answering what tips brain's decline Years before symptoms of Alzheimer's disease appear, two kinds of damaging proteins silently collect in the brain: amyloid beta and tau. Clumps of amyloid accumulate first, but tau is particularly noxious. Wherever tangles of the tau protein appear, brain tissue dies, triggering the confusion and memory loss that are hallmarks of Alzheimer's. … the link between the two proteins may lie in the brain's immune cells that hem in clumps of amyloid. If the immune cells falter, amyloid clumps, or plaques, injure nearby neurons and create a toxic environment that accelerates the formation and spread of tau tangles… Powering up microglia might slow the spread of tau tangles and forestall cognitive decline. The last line might be a little confusing. I found references to CR down regulating microglia and yet other articles suggesting that CR can reduce amyloid. I hope to learn a lot more before incorporating any changes. Cory
  7. corybroo

    Molecular aging midlife crisis

    Just saw the article New Study Identifies Molecular Aging "Midlife Crisis" https://medicalxpress.com/news/2019-06-molecular-aging-midlife-crisis.html Some interesting statements: molecular programs known to promote longevity do not last beyond midlife. study provides a possible new reason why human disease burden increases so sharply from the sixth decade of life onward as health-protective mechanisms disappear key biochemical events regulate the longevity of small short-lived animals ... humans appear to stop using these pathways from about 50 years of age onward a dominant role for the so-called mTOR protein complex—a mechanism that regulates numerous protective cell programs—as well as mitochondrial reactive oxygen species production. These two cellular mechanisms combined to explain about two-thirds of the molecular aging profile in humans While the key protein regulators of longevity and health-span in short-lived animals have been found for the first time to be central to human molecular aging, this new study also determined that many little-studied so-called non-protein-coding genes are involved in human aging. "We've demonstrated that the most valid of 'anti-aging' programs are naturally active in humans and for some reason stop when we reach our 50s," Dr. Wahlestedt said. "This not only provides a specific time window to now study human aging, it also indicates that these established anti-aging strategies may no longer be effective (if too active there can be side effects) and so new approaches will be needed in long-lived humans."
  8. corybroo

    Hong Kong beats the blue zones

    It's good to see improvements somewhere in the world after this news a few days ago. https://www.ajmc.com/focus-of-the-week/millennials-have-worse-health-than-gen-xers-did-at-same-age-driven-by-mental-health
  9. Medical News Today has an article Increased muscle power may prolong life which begins with "Increasing muscle strength is good, but increasing muscle power may be even better for enjoying a longer life" https://www.medicalnewstoday.com/articles/325004.php What's the difference between power and strength? "Muscle power differs from muscle strength in that it relies on generating force and velocity while coordinating movement. For example, lifting a weight one time requires strength, but lifting it several times as quickly as possible requires power." What is the benefit? "participants in quartile one had a risk of dying that was 10 to 13 times higher than that of those in quartiles three and four, while the risk for those in quartile two was still four to five times higher" How to increase power: "choose a weight that is neither easy to lift nor so immense that the person cannot lift it at all. Focus on doing 1 to 3 sets of 6 to 8 repetitions each while moving the weight as quickly as possible"
  10. Medical News Today has an article Time-restricted eating may prevent tumor growth https://www.medicalnewstoday.com/articles/324803.php study in mouse models, have found that time-restricted eating could arrest tumor growth some of the mice unrestricted 24-hour access to food, while the rest had their access to food restricted to the 8-hour window All of the mice also received injections with breast cancer cells for 3 weeks after the start of the experiment. The study results revealed that obese mice on time-restricted diets experienced much less tumor growth than mice who ate unrestrictedly. The results for obese mice on time-restricted diets were, in fact, comparable with those of the lean mice who had unrestricted access to food but received low-fat feed. researchers also found that rodents that had higher insulin levels due to the insulin pump implant had faster tumor growth than control rodents. Conversely, the mice that received diazoxide to lower their insulin levels had slower tumor growth than the control mice. researchers also found that rodents that had higher insulin levels due to the insulin pump implant had faster tumor growth than control rodents. Conversely, the mice that received diazoxide to lower their insulin levels had slower tumor growth than the control mice.
  11. Science Daily has an article "Fasting ramps up human metabolism, study shows" at https://www.sciencedaily.com/releases/2019/01/190131113934.htm "going without food may also boost human metabolic activity, generate antioxidants, and help reverse some effects of aging." "results revealed 44 metabolites, including 30 that were previously unrecognized, that increased universally among subjects between 1.5- to 60-fold within just 58 hours of fasting." " various metabolites whose quantities decline with age, including three known as leucine, isoleucine, and ophthalmic acid. In fasting individuals, these metabolites increase in level" "authors suggest that these antioxidative effects may stand as the body's principal response to fasting, as starvation can foster a dangerously oxidative internal environment. ... fasting might boost production of several age-related metabolites, abundant in young people, but depleted in old."
  12. Medical News Today has the results of the effect of cold on different strains of Rotifers. The most striking finding was that low temperature was not always positive." "The change in the median lifespan of each strain ranged from a decrease of 6 percent to an increase of 100 percent. The team also observed "differences in maximum and relative lifespan extension and in mortality rate." It also saw that in most strains, low temperature extended the "reproductive period and shortened the post-reproductive period, suggesting an extension of healthspan in most strains." It ends with the following "This means we really need to pay more attention to genetic variability in thinking about responses to aging therapies. That is going to be really important when we try to move some of these therapies into humans."
  13. Medical News Today has an article Melanoma: More evidence that antioxidants speed up tumor spread https://www.medicalnewstoday.com/articles/323574.php "Although it may be true that antioxidants protect healthy cells, a growing body of research shows that they also protect cancer cells." "show that dietary antioxidant supplementation increases metastasis in malignant melanoma," "mitochondria-targeted antioxidants do not inhibit cancer progression." "people with cancer or who have a high risk of developing it should avoid the use of antioxidant supplements."
  14. Medical News Today has an article How and why our bodies starve gut bacteria (https://www.medicalnewstoday.com/articles/323509.php) > The results of Reese and colleagues' analysis revealed that bacteria are kept on a short leash in the human gut: they have access to around 1 nitrogen atom per every 10 carbon atoms. This is much less than what free-living microbes get: 1 nitrogen atom to every 4 carbon atoms, on average. The more protein the researchers gave the mice, the more the number of gut bacteria increased. "Our findings," says David, "support the idea that we've evolved a way to keep our bacteria on a leash by leaving them starving for nitrogen." ...why the Western diet might be bad for us. When people eat too much protein, it swamps the host's ability to take up that nitrogen in the small intestine, and more of it ends up making its way to the large intestine, eliminating our ability to control our microbial communities."
  15. Medical News Today had an article about looking at the "healthy" tissue and the mutations therein. Cancer: Even healthy tissue is 'riddled with mutations' https://www.medicalnewstoday.com/articles/323392.php Based on an article at http://science.sciencemag.org/content/early/2018/10/17/science.aau3879 that I do not have access to. The researchers "sampled healthy tissue from the esophagi of nine individuals aged 20–75. None of these people had any history of esophageal cancer or other medical issues with that part of their body." Next, they carried out whole-genome sequencing to map the presence of mutated cells in these healthy samples. They found that, to their surprise, people in their 20s had hundreds of mutations in each cell. In older participants, this figure rose to more than 2,000 per cell Mutations in some genes gave the cells a competitive advantage, meaning that, as they divided and conquered, they outcompeted cells without the mutation and colonized large patches of tissue; this created a patchwork of mutant cells. I interpret this as being one of the reasons apoptosis (as generated by CR) is beneficial. My *guess* is that apoptosis is likely to go after the most different cells first. Cory
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