Kapahi says the molecular mechanisms involved in how dietary restriction slows cancer and extends lifespan have been largely unknown. "This study gets us closer to understanding that process and gives us better targets for both designing and testing drugs which could mimic the effects of dietary restriction in humans," said Kapahi.

The research involved nematode worms that were genetically altered to both under and over-express HIF-1. The animals, which are the most-often used model to study aging, were fed different diets. Animals that were designed to over-express HIF-1 did not get the benefit of lifespan extension even though their diets were restricted. Animals that under-expressed HIF-1 lived longer, even when they had a nutrient-rich diet. Furthermore, it was found that the lifespan extension resulting from dietary restriction required activity in signaling pathways in the endoplasmic reticulum, the part of the cell involved in processing and the proper folding of proteins. This finding supports the theory that aging stems from the effects of misfolded proteins and opens up a rich area of investigation to examine the mechanisms by which stress in the endoplasmic reticulum affects lifespan.

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