Scientists from Harvard and the University of NSW seemed to have managed to reverse the ageing process. In studies conducted on mice a chemical was used to rejuvenate muscle and produced the equivalent of transforming a 60-year-old's muscle to that of a 20-year-old.
Researchers used the chemical nicotinamide adenine dinucleotide (NAD) which is found in all living cells. As levels of NAD fall the cell's mitochondria, which produce energy, are disrupted. As time goes on, communication between mitochondria and the cell nucleus declines, leading to ageing.
As researchers boosted the levels of NAD in mice, the ageing process was not only halted but reversed. One week of receiving injections of NAD saw muscles in the two-year-old mice become akin to those of a six-month-old.
David Sinclair, who is based at Harvard Medical School said:
The ageing process we discovered is like a married couple: when they are young, they communicate well, but over time, living in close quarters for many years, communication breaks down.
And just like a couple, restoring communication solved the problem.
Human trials of the process may be starting as early as next year.
Dr Ana Gomes, from the department of genetics at Harvard Medical School, said:
From what we know so far we don't think you'd have to take it from 20 years until we die.
It seems we can start when we're already old, but not too old that that we're already damaged.
If started at 40 you would probably have a much nicer window of health ageing - but I would guess that, we have to do clinical trials.
Researchers at the Buck Institute for Research on Ageing in collaboration with the Georgia Institute of Technology succeeded in reversing the ageing process in human adult stem cells in 2011.
The researchers found that when regular cells age, the caps on the end of their chromosomes (known as telomeres) get shorter. Its thought that many age-related problems are due to the shortening of these telomeres.