Harvard scientists reverse the ageing process in mice.

“What we saw in these animals was not a slowing down or stabilisation of the ageing process. We saw a dramatic reversal — and that was unexpected.”
–Ronald DePinho, who led the study, which was published in the journal Nature.

The Harvard group focused on a process called telomere shortening. Most cells in the body contain 23 pairs of chromosomes, which carry our DNA. At the ends of each chromosome is a protective cap called a telomere. Each time a cell divides, the telomeres are snipped shorter, until eventually they stop working and the cell dies or goes into a suspended state called “senescence”. The process is behind much of the wear and tear associated with ageing.
At Harvard, they bred genetically manipulated mice that lacked an enzyme called telomerase that stops telomeres getting shorter. Without the enzyme, the mice aged prematurely and suffered ailments, including a poor sense of smell, smaller brain size, infertility and damaged intestines and spleens. But when DePinho gave the mice injections to reactivate the enzyme, it repaired the damaged tissues and reversed the signs of ageing.

“These were severely aged animals, but after a month of treatment they showed a substantial restoration, including the growth of new neurons in their brains.”–DePinho.

DePinho said the treatment might be safe in humans if it were given periodically and only to younger people who do not have tiny clumps of cancer cells already living, unnoticed, in their bodies.
Lynne Cox, a biochemist at Oxford University, said the study was “extremely important” and “provides proof of principle that short-term treatment to restore telomerase in adults already showing age-related tissue degeneration can rejuvenate aged tissues and restore physiological function.”
DePinho said none of Harvard’s mice developed cancer after the treatment. The team is now investigating whether it extends the lifespan of mice or enables them to live healthier lives into old age.