anti aging drug quercitin, apple peel anti-aging
Anti-ageing drug quercetin is found in apple peel
We're beginning to understand the causes of ageing and how to reverse it - thanks to an extract from apple peel. A team has found that a combination of dasatinib - a leukaemia drug - and quercetin - an extract from apple peel - can make elderly mice live 36 per cent longer.

These drugs were chosen for their ability to selectively kill so-called senescent cells. These abnormal cells are in the process of breaking down, but they resist dying. They usually start appearing in the human body in our 60s, although they can arise much earlier in people who are obese or experience a chronic disease.

Some have suggested that these cells themselves catalyse the ageing process, kicking it into action. Now James Kirkland of the Mayo Clinic in Rochester, Minnesota, and his colleagues have shown that this does seem to be the case. When they injected small numbers of senescent cells into young, 6-month-old mice, the animals' speed, endurance and strength fell by 20 to 50 per cent within a few weeks, sinking to the level of a typical elderly, 2-year-old mouse.

"We wouldn't believe it for a long time, so we did it again and again and again," says Kirkland. "It was weird to get this result with so few cells."

Healthier old age

To block the effect of senescent cells, the team looked for drugs that might destroy them - known as "senolytic" drugs. They selected a combination of dasatinib and quercetin because both interfere with the way that senescent cells avoid death.

When they gave this combination to young mice that had aged due to injected cells, these mice then recovered 50 to 100 per cent of their lost physical capabilities within two weeks.

When the team gave the drugs to old mice - aged between 24 and 27 months old - the speed, endurance and strength of these mice improved by between 30 and 100 per cent, and their remaining lifespan was 36 per cent longer than those that weren't given the drugs.

"This is a very important result, and the deleterious effect of the transplanted cells is probably the best confirmation yet that senescent cells are actively toxic," says Aubrey de Grey, founder of the SENS Research Foundation on ageing in Mountain View, California. "More potent senolytic drugs are definitely coming, and I'm betting they'll have a considerably greater effect."

Journal reference: Nature Medicine, DOI: 10.1038/s41591-018-0092-9