Scientists have discovered that taurine concentrations in the blood depend more on individual characteristics than on age. They reached this conclusion after measuring the levels of this amino acid over the lifespan of nearly a thousand people in three cohorts. Thus, the authors of the article, published in Science, cast doubt on the hypothesis that taurine can be used as a marker of aging.
The amino acid taurine is not a component of proteins, but it performs many important functions in the body. It exhibits antioxidant and anti-inflammatory activity. It is also essential for the proper functioning of the cardiovascular, nervous, and digestive systems. Recent studies have focused on the role of taurine in aging, even suggesting it as a marker of aging. We previously reported how scientists discovered that serum taurine concentrations decline with age in mice, rhesus macaques, and humans. Furthermore, a study in mice showed that dietary taurine supplementation prolongs lifespan and improves health.
Now, another group of scientists, led by Rafael de Cabo of the National Institute on Aging in Baltimore, has cast doubt on their colleagues' findings. He and his colleagues analyzed blood taurine levels in people aged 26 to 100 years from three cohorts: the BLSA (742 people), the PREMED (159 people), and the Balearic Study (72 people). Blood samples were collected three to five times throughout life to track long-term trends in blood taurine levels in the same individuals.
The researchers obtained results that contradicted the findings of previous studies: taurine concentrations tended to increase with age (p < 0.001). Moreover, their levels varied across cohorts. For example, in the largest BLSA cohort, taurine levels increased on average from 58.81 micromoles per liter to 74.47 micromoles per liter in women, and from 64.42 micromoles per liter to 67.99 micromoles per liter in men. In the Balearic study cohort, taurine levels also increased from an average of 36 micromoles per liter to 62.3 micromoles per liter in women and from an average of 37.7 micromoles per liter to 50.3 micromoles per liter in men. However, in the PREMED cohort, taurine levels did not change with age in men, although they generally increased in women. The researchers also measured taurine levels in mice and obtained similar results: taurine levels increased with age in females, while they remained unchanged in males. Furthermore, using linear regression, the scientists found that individual differences in taurine levels were more significant than age-related differences. Therefore, taurine cannot be used as a biomarker of aging. While remaining within normal limits, taurine concentrations vary significantly depending on the study group and gender. Several years ago, taurine was also proposed for skin rejuvenation. In experiments, it served as an osmolyte and prevented age-related skin dryness and wrinkling.
