Administrating a molecule that naturally decreases in concentration during human aging significantly extends the cellular lifespan. This finding, published online in Nature Cell Biology, sheds light on how to extend longevity in specific cells.
Aging is associated with various biochemical changes in mammalian cells, such as the decrease of the molecule spermidine within cells. Spermidine is known to be necessary for cell growth and maturation; however it was unclear if its decrease was the cause or consequence of aging.
Frank Madeo and colleagues found that administered spermidine to flies, worms and yeast extended the lifespan of these organisms. Similarly, they found that addition of spermidine to culture medium prolonged the lifespan of human immune cells. ?The findings of the team suggest that spermidine has this effect on cells and ultimately organisms because it provides an alternative mechanism for cellular "clean up". Instead of a damaged cell initiating programmed cell death, spermidine sets in motion a pathway that discards unnecessary and potentially damaging debris within the cell itself.