The Age of the Brain: How 13 Types of Proteins in the Blood Can Give Clues

The abundance of 13 types of proteins in the blood appears to be a strong indicator of how quickly the brain is aging. This suggests that blood tests could one day help people track and even improve their brain health.

Most previous studies have looked at protein markers of brain aging in the blood. Less than 1000 peoplesay nicolas seyfried from Emory University in Atlanta, Georgia, was not involved in the new study.

To get a broader idea of ​​the effects of these proteins, Liu Weishi Researchers from Fudan University in China analyzed MRI brain scan data from around 11,000 adults (approximately 50 to 80 years old at the time of the images) who took part in the UK Biobank project.

Liu's team trained an artificial intelligence model using data from 70% of the participants to determine features of brain images, such as the size of different brain regions and how different parts are connected to each other. The age of the participants was predicted based on When the model was applied to the remaining 30% of participants, its predictions were accurate to within 2.7 years of their actual age.

The researchers then used the model to predict the age of another group of about 4,700 people, with an average age of 63, who also underwent brain imaging for UK Biobank. The researchers calculated the difference between these participants' actual ages and their AI-predicted ages, called the brain age gap. “The higher the age predicted by the AI ​​compared to the actual age, the faster the brain ages,” Liu says.

The group also provided blood samples around the same time as the brain imaging. From this, the research team identified eight proteins that appear to increase in abundance as brain age increases, and five proteins that appear to decrease in abundance.

In an analysis of data from previous studies, researchers confirmed that these proteins are produced by brain cells and that their levels can influence the risk of dementia and stroke.

This suggests that blood tests for these proteins may reveal how quickly the brain ages. “These markers may be canaries in the coal mine that say, 'Hey, look, let's start doing interventions that slow brain aging while there's still plenty of time,'” Seyfried said.

But for this to be helpful, we need to know that these proteins can change with lifestyle changes. “If I run this much, I'll lose this much weight, if I change my diet, [then] We can correct these levels and bring them back into normal range,” Seyfried says.

Because the study was conducted primarily among wealthy white people, Seyfried said more research is needed to see if the results hold true for other populations with more diverse ethnicities and income levels.

The research team now hopes to conduct studies in animals to determine exactly how the 13 proteins affect the brain. For example, researchers might test whether disrupting levels of these proteins affects cognition or even the development of neurodegenerative conditions, Liu says. “In the coming decades, this could open up ways to target proteins to slow aging and disease.”