Japanese scientists have discovered metabolites - substances created during metabolism - that are specifically related to ageing and shed light on how the human body ages.
Researchers from Okinawa Institute of Science and Technology Graduate University (OIST) and Kyoto University in Japan obtained blood samples, including red blood cells (RBCs) from 30 healthy individuals - 15 young adults and 15 older adults.
Then they used Liquid Chromatography-Mass Spectrometry (LC-MS), a technique that separates liquids and detects substances, to identify the metabolites within the blood.
From there, they could calculate the coefficients of variation, or the standard deviation of metabolite abundance divided by the average, to identify which compounds had increased or decreased in the older adults.
"We found 14 age-related compounds. Of these 14 compounds, half of the them had decreased in elderly people," said Yanagida from OIST.
"The decrease was found in antioxidants and in compounds related to muscle strength. Therefore, elderly people had less antioxidants and less muscle strength," Yanagida said.
The other half of the compounds that had increased were metabolites related to declining kidney and liver function, researchers said.
"Some of the age-related metabolites that are found on the same metabolic pathways have connected changes, which suggests that age affects them simultaneously," said Yanagida.
"Functionally related compounds show the same tendencies to increase or decrease with age, or in other words, they show similar correlations," he said.
Now that these age-related metabolites have been identified, the decline in antioxidants and muscle strength suggest that it is important for individuals to consume foods high in antioxidants and to continue exercising, especially after the age of 65, researchers said.
This could help increase the levels of the related metabolites in the body and improve body conditions, they said. The findings were published in the journal PNAS.