2 June 1998
Key Factor In Ageing Uncovered
They may not have discovered the Fountain of Youth, but researchers at The Hospital for Sick Children (HSC), the University of Toronto and the University of Guelph have identified a critical weakness in our defence against ageing. Using the fruit fly as a model biological system, the team have successfully isolated a specific cell type, the motor neuron, that is a major target for oxidative damage - a key factor affecting ageing and life span. By inserting the human gene SOD1 (superoxide dismutase), known to protect against oxidative damage, they were able to increase the average life span of the flies by 40 per cent.
"The research is significant because it clears up a long-standing mystery: which cells, when targeted by oxidative damage, limit the life span of the entire organism," says HSC's Gabrielle Boulianne, leader of the study. "In addition, we now know that just one gene, targeting one type of cell, has a huge impact on ageing.
Contrary to what was previously thought - that many different factors contribute to ageing - it now appears that the process may be simpler."
The discovery won't make us any younger, but it might help stave off the inevitable just that little bit longer. In addition, it could lead to a better understanding of such neurodegenerative diseases as Huntington's, Parkinson's and Alzheimer's. All have been linked to oxidative damage.
"One of life's little ironies is that the stuff we need to survive, oxygen, is actually toxic," comments Guelph's John Phillips. "When we breathe, toxic by-products called oxygen radicals are created. Our cells defend against these toxins by either neutralizing or eliminating them. But as we age it becomes more difficult for our cells to cope with the toxins and they accumulate. What we now know is that the nervous system is the most vulnerable to this accumulation because it uses a lot of oxygen."