How can you determine someone’s age? Of course, you could scan their driver’s license or check for wrinkles and grey hair on their face.
However, as researchers just discovered in a new study, you may also come quite close to the answer by doing a blood test. For long years, scientists believed that age-related alterations in blood components may yield fresh insights into age-related disease biology via experiments involving the exchange of blood between young and elderly animals. After all, because aging is a major risk factor for various chronic illnesses that shorten life expectancy, identifying blood indicators and targets that inform and attenuate aging is a smart undertaking. The ultimate goal is for researchers to be able to alter aging systems in order to stave against illness.
A study conducted by Lehallier and colleagues at Stanford University looked at nearly 3,000 plasma proteins from thousands of adults ranging in age from 18 to 95 years old. They discovered that there are age-related waves of complex changes in the protein composition of human plasma — the liquid rather than the cellular component of blood. This research on aging, which was published in Nature Medicine, discovered unanticipated markers and pathways that may serve as prospective therapeutic targets for age-related disorders.
Blood Flows with Age-Related Particles
Researchers have long known that as we age, the makeup of our plasma — the liquid element of our blood that is devoid of cells — changes. Cells, physiological fluids, and tissues all have a protein composition that changes with age, and the protein composition of these tissues, bodily fluids, and cells can give insight into complicated biological processes since proteins are frequently direct regulators of cellular pathways. Researchers have looked specifically at blood, which contains proteins from practically every cell and tissue, in order to uncover chemicals that may have an impact on aging.
The trials using heterochronic parabiosis, which is a medically produced situation in which the circulatory systems of young and elderly mice are connected, provide some of the strongest evidence that blood may be used to study aging. This research demonstrates that aging mice can have their tissues revived, including their muscles, liver, heart, pancreas, kidney, bone, and brain, among other organs. Infusion of old plasma into young mice accelerates brain aging, while an infusion of young plasma slows brain aging. These findings support the idea that plasma protein composition contains critical aging regulators and that protein signature might help us understand how humans age.
Predicting Age Via Drop Of Blood
In this study, Lehallier and colleagues looked at the protein composition of plasma from persons as young as 18 years old to those as old as 90 years old. They analyzed 2,925 plasma proteins from 4,263 individuals ranging in age from young adults to nonagenarians. Over the course of their research, they observed variations in the quantities of 1,379 proteins, and they connected these alterations to biological pathways and illness.
When Lehallier and colleagues looked at plasma protein composition variations in the fourth, seventh, and eighth decades of life, they discovered waves of change. Each of these age-related protein signatures represented a separate biological route, and they were found to be associated with age-related illnesses and characteristics. For example, individuals who were predicted to be younger than their chronological age performed better on cognitive and physical tests.
Gender-Based Difference of Age Prediction
Despite the fact that men and women age differently, Lehallier and colleagues discovered that two-thirds of proteins varied with sex (895 of 1,379 proteins). This suggests that a unique proteomic clock may be used to forecast age in men and women and that changes in age-related illnesses and features are connected.
A panel of 373 proteins was identified by Lehallier and colleagues, which can be used to assess the relative health of a person and to measure their health span over the course of a lifetime. All of this is possible with just a single drop of blood.