Proteomics studies which proteins are present, how much of each is present and, in some methods, their modifications, interactions or activity. Most blood-based proteomic clocks use the measured concentrations of selected plasma proteins to produce a statistical prediction.
Methylation clocks analyse chemical modifications to DNA. Proteomic clocks analyse proteins that change as tissues and immune cells respond to disease, medicines, exercise and other conditions. Some concentrations change within hours; others change much more slowly.
Organ-specific protein profiles
Some circulating proteins originate mainly from particular organs. Models built from these subsets estimate an organ-associated age profile. They sample plasma, however, and cannot directly measure all the processes occurring inside a kidney or brain.
A September 2026 Nature Communications study trained 16 organ- and system-specific clocks using 53,014 UK Biobank participants, then tested them in an independent Chinese cohort of 3,977. Their associations with diseases and exposures may help identify risk. The study did not test interventions that lower an organ-age score.
Rentosertib: six clocks in one trial
Insilico tested rentosertib in a 12-week Phase 2a trial for idiopathic pulmonary fibrosis. A later analysis applied six proteomic ageing clocks to blood samples from 42 participants. Some treatment groups had lower predicted ages than placebo, particularly at week four.
The trial was small and brief, and all participants had a serious lung disease. Changes in inflammation, fibrosis or metabolism could account for some of the clock responses. The six models draw on related protein measurements from the same participants; agreement between them cannot establish longer lifespan.
What a lower reading can establish
A proteomic clock can help identify physiological responses to treatment and suggest which organ systems deserve closer investigation. Evidence for broader rejuvenation would need a suitable control group, persistent changes and improvements in function, supported by other measurement methods.
If a patient’s proteomic age falls by five years, that is a five-year change in a model estimate. It cannot yet be converted into five additional years of life.
Sources
- Review · 9 Jul 2026Biological aging clocks in health and disease
Critical review of biological clocks and their uses and limitations.
Checked 24 Oct 2026 - Paper · 9 Sep 2026Atlas of genetic architecture and exploratory temporal interaction networks of plasma protein-based organ and system aging
16 organ/system clocks in 53,014 UK Biobank participants, with independent validation in China Kadoorie Biobank; associations are not proof of causal effects.
Checked 24 Oct 2026 - Paper · 7 Sep 2026Integration of proteomic aging clocks in a phase 2a clinical trial supports simultaneous geroprotective assessment
Exploratory analyses of 42 IPF trial participants, six protein clocks and multiple time points; cannot demonstrate longer survival.
Checked 24 Oct 2026