Reacción a "Universal molecular ‘clocks’ of ageing and mortality identified in mammals"

How old is our body really? The remarkable increase in life expectancy that humanity has experienced over the last century has made ageing the main risk factor for numerous conditions, such as neurodegenerative diseases, cardiovascular diseases and cancer. Thus, the development of tools to quantify the biological deterioration of the body and evaluate gerotherapeutics capable of slowing down some of the biological processes associated with old age could have a decisive impact on the prevention and treatment of these conditions.

With this aim in mind, more than 11,000 transcriptomes from biological tissue samples of humans, primates and rodents of different ages have been used by Vadim Gladyshev’s group at Brigham and Women’s Hospital and Harvard Medical School to construct so-called ‘ageing clocks’: mathematical models that allow the ‘biological age’ of an organism to be estimated, a measure of accumulated biological decline that may reflect actual health status better than the number of years elapsed since birth. Furthermore, unlike the well-known ‘epigenetic clocks’, which are based on chemical modifications to DNA that occur over time, this study is based on changes in gene activity, providing more direct information on how cells function and, consequently, offering a highly useful additional layer of insight.

One of the most striking findings of the study is that certain interventions — such as calorie restriction without malnutrition or the controlled administration of certain nutritional supplements — manage to mitigate or even reverse some of these biological processes associated with old age. Furthermore, the study stands out for its high technical quality, underpinned by the large scale and diversity of the data analysed, and demonstrates the scientific and medical potential of ageing clocks.

Its translation into clinical practice will require overcoming certain obstacles, such as the technical challenges associated with working with RNA, a molecule that is more easily degraded than DNA and therefore requires more stringent protocols. In any case, this study represents a solid contribution that reinforces the importance of quantifying biological ageing and consolidates the role of ageing clocks as benchmark tools in this field.