At 118, the Frenchwoman Lucile Radon, or Sister André, became the dean of humanity last month. She succeeds Japanese Kane Tanaka, who died at the age of 119. Ages that make you dizzy. But some scientists are trying to push the limits ever further, like Jean-Marc Lemaître. He gave himself a mission: to rejuvenate our cells.
The researcher at the Institute of Regenerative Medicine takes us on a tour of his lab. “It’s the machine to rejuvenate”laughs the researcher in the middle of hoods and incubators.
“We control the humidity or the oxygen level, to be sure that the cell that is produced is really of high quality. It is then of course tested.”
Jean-Marc Lemaitreat franceinfo
It is in these machines that his team manipulates the cells to reprogram them. “Cell reprogramming, finally, started after the discovery of Mr. Yamanaka who is a Japanese professor who was able to show that one could, with a cocktail of factors, reprogram a cell, that is to say convert it into an embryonic stem cell”explains Jean-Marc Lemaître.
These stem cells can then multiply again and regenerate tissues. Jean-Marc Lemaître, he went further by taking skin cells from centenarians a priori impossible to reprogram. But his team still managed, in 2011, to give them a new lease of life: “It allowed us to finally demonstrate that cellular aging was reversible and it was the first time that we demonstrated this concept.”
“If we know that aging is reversible, we can try to find strategies to apply it and rejuvenate, regularly or not, aging cells.”
Jean-Marc Lemaître, researcherat franceinfo
His elixir of youth is composed of very specific genes. The scientist tried to apply it to mice and the results are more than satisfactory. “For example, if you induce the genes throughout the life of the mouse at low rates, you gain 30% of healthy life.says Jean-Marc Lemaître. And if we do just one reprogramming early in life, we still gain 15% of healthy life with an improvement in physiological functions. Age-related pathologies are delayed or even eliminated.”
But researchers still have many hurdles to overcome to conduct human trials. In the United States, the quest for immortality interests billionaires like Jeff Bezos, the boss of Amazon, who has invested three billion dollars in a company specializing in cell rejuvenation.