Ageing begins before we are born: Research

COURTESY HINDUSTAN TIMES

The process of ageing begins even before we are born, researchers say, adding that providing mothers with antioxidants during pregnancy may help their offspring to age more slowly in adulthood. Researchers from the University of Cambridge in the UK used rats to model pregnancy and foetal development.

The offspring of mothers with lower levels of oxygen in the womb — which, in humans, can be a consequence of smoking during pregnancy or during pregnancy at high altitude — aged more quickly in adulthood, researchers said.

Our DNA is ‘written’ onto chromosomes, of which humans carry 23 pairs. The ends of each chromosome are known as telomeres and act in a similar way to the plastic that binds the ends of shoelaces, preventing the chromosomes from fraying, they said. As we age, these telomeres become shorter and shorter, and hence their length can be used as a proxy to measure ageing.

For the study, researchers measured the length of telomeres in blood vessels of adult laboratory rats born from mothers who were or were not fed antioxidants during normal or complicated pregnancy.

The most common complication in pregnancy is a reduction in the amount of oxygen that the baby receives – this can be due to a number of causes, including expectant mothers who smoke or who experience preeclampsia.

To simulate this complication, the researchers placed a group of pregnant laboratory rats in a room containing 7% less oxygen than normal. Researchers found that adult rats born from mothers who had less oxygen during pregnancy had shorter telomeres than rats born from uncomplicated pregnancies, and experienced problems with the inner lining of their blood vessels — signs that they had aged more quickly and were predisposed to developing heart disease earlier than normal.

However, when pregnant mothers in this group were given antioxidant supplements, this lowered the risk among their offspring of developing heart disease. Even the offspring born from uncomplicated pregnancies — when the foetus had received appropriate levels of oxygen — benefited from a maternal diet of antioxidants, with longer telomeres than those rats whose mothers did not receive the antioxidant supplements during pregnancy.

“Our study on rats suggests that the ageing clock begins ticking even before we are born and enter this world, which may surprise many people,” said Dino Giussani from the University of Cambridge. “We already know that our genes interact with environmental risk factors, such as smoking, obesity and lack of exercise to increase our risk of heart disease, but here we have shown that the environment we are exposed to in the womb may be just as, if not more, important in programming a risk of adult-onset cardiovascular disease,” said Giussani. The findings were published in The FASEB Journal.