I had previously written about the possibility of using epigenetic markers as a method of gauging our biologic age, but an alternative set of markers may prove more promising. A very intriguing and captivating article was published, yet again in Nature, describing how a group of researchers used 4,979 proteins in a total of 5,676 subjects to generate an “organ-specific plasma proteome” that could predict organ-specific aging in the human body!
The researchers generated aging models for 11 major organs and tissues— adipose tissue, artery, brain, heart, immune tissue, intestine, kidney, liver, lung, muscle and pancreas. While you might have expected that markers for “extreme aging” would have been present across all organs and tissues, the researchers actually found variation within a given individual, including differences in organ-specific biologic aging! Additionally, the researchers stated in their article, “A standard deviation increase (approximately four years of extra organ aging…) in heart, adipose, liver, pancreas, brain, lung, immune or muscle age gap each conferred between 15–50% increased all-cause mortality risk.”
Findings in the analysis regarding the brain, using the expanded protein markers in the study, highlighted that molecular information about brain aging was able to predict predict progression of dementia in a manner that is not captured by other approaches, including plasma pTau-181, which is currently being used as a biomarker for Alzheimer’s disease.
In the same way that we currently use blood tests to detect early organ dysfunction (for example creatinine for kidney disease and ALT for liver disease), this expanded use of serum protein markers has the potential to dramatically increase our ability to detect organ-specific aging and early markers of disease in the human body! The possibility of having such a robust assessment of the wellbeing of the human body is very exciting.
The authors conclude with a riveting comment: “The resulting organ aging models can predict mortality, organ-specific functional decline, disease risk and progression and aging heterogeneity between tissues. This approach is minimally invasive, requiring only a small blood sample, and could be easily applied to understand the effects of health interventions, such as lifestyle modifications and drug therapies, at the organ level.”
Another example of medical literature that generates hope and excitement for the future of healthcare!
