Stanford scientists have identified specific biological pathways along which individuals age over time.
What’s your type?
That question could gain new meaning, thanks to scientists who’ve categorized how humans age into different classes dubbed “ageotypes,” reports a new study from the Stanford University School of Medicine.
“We know already there are a handful of nice molecular and clinical markers, such as high cholesterol, that are more common in older populations,” said Michael Snyder, PhD, professor and chair of genetics. “But we want to know more about aging than what can be learned from population averages. What happens to an individual as they age? No one has ever looked at the same person in detail over time.”
Now, Snyder and his team have done just that: They profiled a group of 43 healthy men and women between the ages of 34 and 68, taking extensive measurements of their molecular biology at least five times over two years.
The researchers determined that people generally age along certain biological pathways in the body: metabolic, immune, hepatic (liver) and nephrotic (kidney). People who are metabolic agers, for example, might be at a higher risk for diabetes or show signs of elevated hemoglobin A1c, a measure of blood-sugar levels, as they grow older. People with an immune ageotype, on the other hand, might generate higher levels of inflammatory markers or be more prone to immune-related diseases as they age. But the ageotypes are not mutually exclusive, and a metabolic ager could also be an immune ager, for example.
Using blood, stool and other biological samples, the study tracked levels of certain microbes and biological molecules, such as proteins, metabolites and lipids, in participants over two years, monitoring how the levels changed over time.