Scientists conducted the study using worms, that allegedly have mechanisms that are similar to those of mammals.
Investigators found that as worms die, death can be seen spreading through their bodies as a "fluorescent blue light caused by necrosis" literally lighting up the cell death pathway.
David Gems from the Institute of Health Aging at University College London, who led the study, explained:
“We’ve identified a chemical pathway of self-destruction that propagates cell death in worms, which we see as this glowing blue fluorescence traveling through the body. It’s like a blue grim reaper, tracking death as it spreads throughout the organism until all life is extinguished.”
According to the findings, individuals don't simply die in an instant. Instead, individual cell deaths trigger a chemical reaction that leads to the breakdown of cellular components. If this process goes unstopped the individual will die, but according to Gems, it can be delayed.
“We found that when we blocked this pathway, we could delay death induced by a stress such as infection, but we couldn’t slow death from old-age,” Gems said. “This suggests that aging causes death by a number of processes acting in parallel.” Scientists compared the reaction that leads to the breakdown of cell components to the damage caused by aging. However, they noted that cells that have aged out of commission cannot be revived.
“The findings cast doubt on the theory that aging is simply a consequence of an accumulation of molecular damage," Gems said. "We need to focus on the biological events that occur during aging and death to properly understand how we might be able to interrupt these processes.”