July 10, 2013
Rate Of Ageing Tied To Birthweight, Metabolites
Rebekah Eliason for redOrbit.com - Your Universe Online
Scientists have discovered a clue towards understanding the rate of ageing and overall health of individuals later in life. Metabolites are leftover chemical fingerprints derived from molecular changes before birth or during infancy that may provide this new insight.King's College London published a study of twins in the International Journal of Epidemiology that emphasized how, through metabolic profiling, 22 metabolites associated with ageing were identified. A specific metabolite, C-glyTrp, connected to lung function, bone mineral density, cholesterol and blood pressure is also strongly tied to birth weight, which is a well-known factor associated with healthy ageing. Researchers linked levels of C-glyTrp to birth weight by comparing identical twins' birth weights and metabolite levels.
This discovery suggests that levels of the new metabolite may be an indicator for accelerated ageing. Production amounts of C-glyTrp may be determined in the womb and affected by prenatal nutrition. Professor Tim Spector, Head of the Department of Twin Research at King's College London, explained, "Scientists have known for a long time that a person's weight at the time of birth is an important determinant of health in middle and old age, and that people with low birth weight are more susceptible to age related diseases. So far the molecular mechanisms that link low birth weight to health or disease in old age had remained elusive, but this discovery has revealed one of the molecular pathways involved."
To further investigate the connection between C-glyTrp and birth weight, researchers showed through genetic tests that the gene influencing metabolite levels could be modified by chemical switches affected by environmental factors or lifestyle choices. These types of changes, known as epigenetic changes, could affect a person's metabolism which influences risk level for age related diseases.
Ana Valdes, lead researcher from King's, explained that "Human ageing is a process influenced by genetic, lifestyle and environmental factors, but genes only explain a part of the story. Molecular changes that influence how we age over time are triggered by epigenetic changes. This study has for the first time used analysis of blood and epigenetic changes to identify a novel metabolite that has a link to birthweight and rate of ageing."
"This unique metabolite, which is related to age and age related diseases, was different in genetically identical twins that had very different weight at birth. This shows us that birthweight affects a molecular mechanism that alters this metabolite. This may help us understand how lower nutrition in the womb alters molecular pathways that result in faster ageing and a higher risk of age-related diseases fifty years later," she said.
"Understanding the molecular pathways involved in the ageing process could ultimately pave the way for future therapies to treat age-related conditions. As these 22 metabolites linked to ageing are detectable in the blood, we can now predict actual age from a blood sample pretty accurately and in the future this can be refined to potentially identify future rapid biological ageing in individuals."
This study was funded by the European Commission.