Psst – want to live forever?
Reduction of food intake, commonly referred to as dietary restriction, has been shown to slow ageing and extend lifespan in virtually every biological system examined. However, the underlying mechanisms that couple dietary restriction to lifespan extension remain poorly defined. Recently, the relatively simple eukaryote Saccharomyces cerevisiae (bakers’ yeast) has emerged as a powerful model system to study the genetic and physiological factors that alter lifespan. A recent paper shows that caffeine extends the lifespan of yeast.
This begs the question: can caffeine extend lifespan in humans? Caffeine is the most widely used psychoactive drug worldwide with coffee being the main source of caffeine in the Western diet. Tantalizingly, epidemiological studies have correlated habitual coffee consumption with a decreased relative risk of mortality. Drinking one cup of coffee results in an approximate peak plasma concentration of 1–10 μM caffeine in humans (with an estimated half-life of 2.5–4.5 h). Assuming that caffeine acts in a similar way in humans as in yeast, moderate coffee consumption compares well with the with the levels calculated to be necessary for lifespan extension in yeast, and thus provides mechanistic support for the correlative links between coffee consumption and longevity described above. At this concentration, caffeine does not appear to have deleterious consequences. Finally, caffeine has recently been shown to suppress cell transformation, suggesting that caffeine may also be a (well-tolerated) and effective anti-cancer agent.
Caffeine extends yeast lifespan by targeting TORC1. Molecular Microbiology 27 May 2008
Dietary nutrient limitation (dietary restriction) is known to increase lifespan in a variety of organisms. Although the molecular events that couple dietary restriction to increased lifespan are not clear, studies of the model eukaryote Saccharomyces cerevisiae have implicated several nutrient-sensitive kinases, including the target of rapamycin complex 1 (TORC1), Sch9, protein kinase A (PKA) and Rim15. We have recently demonstrated that TORC1 activates Sch9 by direct phosphorylation. We now show that Sch9 inhibits Rim15 also by direct phosphorylation. Treatment of yeast cells with the specific TORC1 inhibitor rapamycin or caffeine releases Rim15 from TORC1-Sch9-mediated inhibition and consequently increases lifespan. This kinase cascade appears to have been evolutionarily conserved, suggesting that caffeine may extend lifespan in other eukaryotes, including man.
Tags: Biology, Food, Fungi, Health, Medicine, Microbiology, Mycology, Science
I saw that on a Discovery special on the human body. It does look interesting. In escence, you are putting your body in a constant survival mode.
Caloric Restriction with Adequate Nutrition (CRAN) has been our only known arsenal so far to combat ageing. I’ll start drinking coffee right away, now that experiments point toward a conserved sequence on genomes-across-species might give us long life.
As to your “Dietary nutrient limitation (dietary restriction)” the actual words would probably be Caloric Restriction with ‘Adequate’ Nutrition.