Ageing reversed: Scientists increase lifespan of mice by reprogramming their body’s cells

Using a breakthrough technique, scientists have successfully extended life of a mice. Scientists reprogrammed the body cells of the mice and successfully increased the lifespan of the mice.

The breakthrough technique may now lead to new therapeutic approaches that may result in improving the health and longevity in humans.

Researchers at the Salk Institute in the US discovered that intermittent expression of genes normally associated with an embryonic state can reverse the hallmarks of old age.

The experiment prompted human skin cells to look and behave young again. It also rejuvenated a mice which had a premature ageing disease as it countered the signs of ageing and increased its lifespan by 30 per cent.

The early-stage approach has provided insight into the cellular drivers of ageing and possible therapeutic approaches for improving human health and longevity.

“Our study shows that ageing may not have to proceed in one single direction. It has plasticity and, with careful modulation, ageing might be reversed,” said Juan Carlos Izpisua Belmonte, professor at Salk Institute for Biological Studies.

In modern societies, as people live longer, their risk of developing age-related diseases increases.

The biggest risk factor for heart disease, cancer and neurodegenerative disorders is simply age, shows the data.

The study of cellular reprogramming holds one clue to halt or reverse ageing. Cellular reprogramming is a process in which the expression of four genes called Yamanaka factors enables scientists to convert any cell into induced pluripotent stem cells (iPSCs).

Just like embryonic stem calls, iPSCs can divide indefinitely and become any cell type present in our body.

“What we and other stem-cell labs have observed is that when you induce cellular reprogramming, cells look younger.  

The next question was whether we could induce this rejuvenation process in a live animal,” said Alejandro Ocampo, research associate from Salk Institute.

Though cellular rejuvenation that works for laboratory cells sounds desirable, but it is not necessarily a good idea for an entire organism.

For one thing, although rapid cell division is critical in growing embryos, in adults such growth is one of the hallmarks of cancer.

For another, having large numbers of cells revert back to embryonic status in an adult could result in organ failure, ultimately leading to death.

For these reasons, researchers wondered whether they could avoid cancer and improve aging characteristics by inducing the Yamanaka factors for a short period of time.

They turned to a rare genetic disease called progeria.  Both mice and humans with progeria show many signs of aging including DNA damage, organ dysfunction and dramatically shortened lifespan.

Moreover, the chemical marks on DNA responsible for the regulation of genes and protection of our genome, known as epigenetic marks, are prematurely dysregulated in progeria mice and humans.

The study appears in the journal Cell. 

(With inputs from PTI)