A cure for ageing sounds like something right out of a wild science-fiction film like The Substance. But scientists could now be close to making this a reality. Researchers from Osaka University, Japan claim to have found a cellular 'master switch' which can reverse the process of ageing. This protein, called AP2A1, could be the key to future treatments that will turn back the body's biological clock and undo the damage caused by old age. As our bodies get older, we build up a growing number of old or 'senescent' cells which stop dividing and functioning as they should. These...