Hi everyone,
It appears that ageing can be sowed down as much as 30% (in mice) through cellular reprogramming...(changes in the epigenome).
https://www.sciencedaily.com/releases/2016/12/161215143541.htm**********
Scientists have rolled back time for live mice through systemic cellular reprogramming, according to a new study. In mice carrying a mutation leading to premature aging, reprogramming of chemical marks in the genome, known as epigenetic marks, reduced many signs of aging in the mice and extended their lifespan on average from 18 weeks to 24.
The study suggests that epigenetic changes drive the aging process, and that those changes may be malleable. "We did not correct the mutation that causes premature aging in these mice," says lead investigator Juan Carlos Izpisua Belmonte, a professor in the Salk Institute of Biological Science's Gene Expression Laboratory. "We altered aging by changing the epigenome, suggesting that aging is a plastic process."
This is the first report in which cellular reprogramming extends lifespan in a live animal. Previous efforts resulted in mice that either died immediately or developed extensive tumors. The Salk team used a partial cellular reprogramming approach that did not cause tumors or death. "We were surprised and excited to see that we were able to prolong the lifespan by in vivo reprogramming," says co-first author Pradeep Reddy.
Epigenetic marks, which change over a lifetime in response to environmental changes, regulate and protect the genome. Some marks turn on specialized functions, such as skin cell machinery in a skin cell, and turn off mechanisms that aren't needed, such as liver cell machinery. "During aging, marks are added, removed, and modified," says co-first author Alejandro Ocampo. "It's clear that the epigenome is changing as we get older."
"It is difficult to say specifically why the animal lives longer," says co-first author Paloma Martinez-Redondo. "But we know that the expression of these factors is inducing changes in the epigenome, and those are leading to benefits at the cellular and organismal level."
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Cheers.
Sriram