Taurine is Not a Reliable Aging Biomarker

Photo:  PROSTOCK STUDIO/SHUTTERSTOCK

Scientists at NIH have found that levels of circulating taurine, a conditionally essential amino acid involved in multiple important biological functions, is unlikely to serve as a good biomarker for the aging process. In blood samples from humans, monkeys and mice, scientists found that circulating taurine levels often increased or remained constant with age.

Longitudinal data revealed that within individuals, differences in taurine levels often exceeded age-related changes. Researchers also found that taurine levels were inconsistently associated with health outcomes across age, species and cohorts, suggesting that declining taurine is not a universal marker of aging. Instead, its impact may depend on individual physiological contexts shaped by genetic, nutritional and environmental factors. Results are published in Science.

Taurine recently gained popularity as a dietary supplement due to recent research that found supplementation with taurine improved multiple age-related traits and extended lifespan in model organisms (worms and mice). However, there is no solid clinical data to show its supplementation benefits humans.

Researchers measured taurine concentration in longitudinally collected blood from participants in the Baltimore Longitudinal Study of Aging (aged 26-100 years), rhesus monkeys (aged 3-32 years) and mice (aged 9-27 months). Taurine concentrations increased with age in all groups, except in male mice in which taurine remained unchanged. Similar age-related changes in taurine concentrations were observed in two cross-sectional studies of geographically distinct human populations, the Balearic Islands Study of Aging (aged 20-85 years) from the Balearic region of Mallorca, and the Predictive Medicine Research cohort (aged 20-68 years) from Atlanta, Georgia, as well as in the cross-sectional arm of the Study of Longitudinal Aging in Mice.

Researchers also found that the relation between taurine and muscle strength or body weight was inconsistent. Low motor function performance can be associated either with high or low concentrations of taurine whereas, in other cases, no relation at all is found between these variables.