Secret of ageing revealed

Scientists staved off the ageing process in mice, a discovery that could have huge impact.

Scientists have managed to stave off the ageing process in mice, a discovery that might pave the way to longer, healthier living in humans too.

Experiments at the US-based Washington University School of Medicine showed that protecting the body of mice against highly reactive chemicals called free radicals - long suspected as a cause of ageing - gave them longer lives, reports the Scottish daily Scotsman.

Mice given higher levels of an enzyme that breaks down free radicals had about a 20 percent increase in their average and maximum lifespan, about four and a half months.

They also had healthier hearts than other mice.

The experiments suggest that people could live longer and be free from many age-related diseases if they were protected from free radicals.

"This study is very supportive of the free radical theory of ageing. It shows the significance of free radicals and of reactive oxygen species in particular in the ageing process," said lead researcher Peter Rabinovitch.

"People used to only focus on specific age-related diseases because it was believed that the ageing process itself could not be affected. What we'rerealising now is that by intervening in the underlying ageing process, we may be able to produce very significant increases in 'health-span', or healthy life-span."

Rabinovitch and his colleagues studied the enzyme catalase, which helps breakdown hydrogen peroxide - a waste product of the body's metabolic process - into water and oxygen.

Hydrogen peroxide can be a precursor of free radicals.

The damage they cause can, in turn, lead to further flaws in cells' chemical processes, which lead to more free radicals being produced.

Free radicals can create unnecessary chemical reactions, which damage cells,including DNA. Some scientists believe they are major factors in heart disease, cancer and other serious conditions.