Altered genes, altered metabolism - longer life?
Scientists supported by the National Institute on Aging (NIA) have discovered that a gene, named daf-2 , which regulates glucose (sugar) metabolism in a tiny worm, Caenorhabditis elegans , may also affect or enhance its longevity. The findings, in the August 15, 1997 issue of Science , may lead to testable ideas for the way glucose and insulin sensitivity affect human longevity. Lead researcher and NIA grantee Dr. Gary Ruvkun of Massachusetts General Hospital speculates that a downshifting of glucose metabolism in times of stress helps the worm live longer.
Dr. David Finkelstein, of NIA's Biology of Aging program says, "this finding suggests that altering glucose metabolism could be a key to slowing aging in higher organisms, even perhaps in humans." The daf-2 gene is in the same family of proteins as the receptor which binds insulin in humans; it functions as a switchboard for signals coming into the cell which tell the cell how much food is available. If not enough food or insulin is available, the daf-2 gene activates a pathway that puts the organism into a hibernating state. A decrease in metabolism has been observed in calorically restricted rats which have an extended lifespan, suggesting that this mechanism in humans may have the potential for slowing down aging.
The National Institute on Aging, one of the 18 Institutes which make up the National Institutes of Health, leads the Federal effort supporting basic, clinical, epidemiological and social research on aging and the special needs of older people.