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Glucose restriction can extend normal cell lifespan and impair precancerous cell growth through epigenetic control of hTERT and p16 expression. Li Y, Liu L, Tollefsbol TO. FASEB J. 2009 Dec 17. [Epub ahead of print] PMID: 20019239 doi: 10.1096/fj.09-149328 Cancer cells metabolize glucose at elevated rates and have a higher sensitivity to glucose reduction. However, the precise molecular mechanisms leading to different responses to glucose restriction between normal and cancer cells are not fully understood. We analyzed normal WI-38 and immortalized WI-38/S fetal lung fibroblasts and found that glucose restriction resulted in growth inhibition and apoptosis in WI-38/S cells, whereas it induced lifespan extension in WI-38 cells. Moreover, in WI-38/S cells glucose restriction decreased expression of hTERT (human telomerase reverse transcriptase) and increased expression of p16(INK4a). Opposite effects were found in the gene expression of hTERT and p16 in WI-38 cells in response to glucose restriction. The altered gene expression was partly due to glucose restriction-induced DNA methylation changes and chromatin remodeling of the hTERT and p16 promoters in normal and immortalized WI-38 cells. Furthermore, glucose restriction resulted in altered hTERT and p16 expression in response to epigenetic regulators in WI-38 rather than WI-38/S cells, suggesting that energy stress-induced differential epigenetic regulation may lead to different cellular fates in normal and precancerous cells. Collectively, these results provide new insights into the epigenetic mechanisms of a nutrient control strategy that may contribute to cancer therapy as well as antiaging approaches.

"Researchers from the University of Alabama at Birmingham (UAB) have discovered that restricting consumption of glucose, the most common dietary sugar, can extend the life of healthy human-lung cells and speed the death of precancerous human-lung cells, reducing cancer's spread and growth rate. The research has wide-ranging potential in age-related science, including ways in which calorie-intake restriction can benefit longevity and help prevent diseases like cancer that have been linked to aging, said principal investigator Trygve Tollefsbol, Ph.D., D.O., a professor in the Department of Biology. "These results further verify the potential health benefits of controlling calorie intake." Tollefsbol said. "Our research indicates that calorie reduction extends the lifespan of healthy human cells and aids the body's natural ability to kill off cancer-forming cells.

"ScienceDaily (Dec. 17, 2009) - Researchers from the University of Alabama at Birmingham (UAB) have discovered that restricting consumption of glucose, the most common dietary sugar, can extend the life of healthy human-lung cells and speed the death of precancerous human-lung cells, reducing cancer's spread and growth rate. The research has wide-ranging potential in age-related science, including ways in which calorie-intake restriction can benefit longevity and help prevent diseases like cancer that have been linked to aging, said principal investigator Trygve Tollefsbol, Ph.D., D.O., a professor in the Department of Biology. "These results further verify the potential health benefits of controlling calorie intake." Tollefsbol said. "Our research indicates that calorie reduction extends the lifespan of healthy human cells and aids the body's natural ability to kill off cancer-forming cells.""

"ScienceDaily (Dec. 26, 2009) - Going back for a second dessert after your holiday meal might not be the best strategy for living a long, cancer-free life say researchers from the University of Alabama at Birmingham. That's because they've shown exactly how restricted calorie diets -- specifically in the form of restricted glucose -- help human cells live longer. They found that the normal cells lived longer, and many of the precancerous cells died, when given less glucose. Gene activity was also measured under these same conditions. The reduced glucose caused normal cells to have a higher activity of the gene that dictates the level of telomerase, an enzyme that extends their lifespan and lower activity of a gene (p16) that slows their growth. Epigenetic effects (effects not due to gene mutations) were found to be a major cause in changing the activity of these genes as they reacted to decreased glucose levels. "Western science is on the cusp of developing a pharmaceutical fountain of youth" said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "This study confirms that we are on the path to persuading human cells to let us to live longer, and perhaps cancer-free, lives.""

The fact that an animal's lifetime is prolonged by decreasing its sugar ingestion is commonly recognized. In a study published in the journal PLoS Genetics, scientists from the Université de Montréal, reveal that sugar in itself is not the key element but the cells' capacity to detect its presence is.

A signalling pathway that influences how sensitive cancer cells are to the beneficial effects of dietary restriction is described in this week's Nature. Dietary restriction - eating less calories while maintaining essential vitamins and minerals - can extend lifespan, and reduce cancer incidence and growth. But some types of cancer cell are more sensitive to the anti-growth effects of dietary restriction than others, Nada Kalaany and David Sabatini report. The effect hinges on the activity of the phosphatidylinositol-3-kinase (PI3K) pathway. If the pathway is active, dietary restriction has no effect on cancer cells. However, if the pathway is inactive, tumours are sensitive to dietary restriction.

ScienceDaily (May 26, 2009) - A protein that plays a key role in tumor formation, oxygen metabolism and inflammation is involved in a pathway that extends lifespan by dietary restriction. The finding, which appears in the May 22, 2009 edition of the online journal PLoS Genetics, provides a new understanding of how dietary restriction contributes to longevity and cancer prevention and gives scientists new targets for developing and testing drugs that could extend the healthy years of life.

Immortality Institute "For Infinite Lifespans"

"5' AMP-activated protein kinase or AMPK or 5' adenosine monophosphate-activated protein kinase is an enzyme that plays a role in cellular energy homeostasis. It consists of three proteins (subunits) that together make a functional enzyme, conserved from yeast to humans. It is expressed in a number of tissues, including the liver, brain, and skeletal muscle. The net effect of AMPK activation is stimulation of hepatic fatty acid oxidation and ketogenesis, inhibition of cholesterol synthesis, lipogenesis, and triglyceride synthesis, inhibition of adipocyte lipolysis and lipogenesis, stimulation of skeletal muscle fatty acid oxidation and muscle glucose uptake, and modulation of insulin secretion by pancreatic beta-cells.[1] It should not be confused with cyclic AMP-activated protein kinase (protein kinase A), which, although being of similar nature, may have opposite effects.[2]"

Study finds that fiber from grains, like oatmeal, cornmeal, and brown rice reduces risk of dying early from disease. Fiber from fruit and vegetables and beans (although healthy) don't count.