Nicotinamide Adenine Dinucleotide (NAD)-Dependent Protein Deacetylase, Sirtuin, as a Biomarker of Healthy Life Expectancy: A Mini-Review.

Although a variety of disease-specific biomarkers have been identified for common lifestyle- or aging-related diseases, there are currently no indices available to measure general health or the existence of pre-symptomatic conditions in various types of tissue and organ damage. A rising body of research suggests that sirtuins may have the potential to be used as an index to assess overall health status and the existence of pre-symptomatic illness states. Sirtuins (SIRTs) are nicotinamide adenine dinucleotide (NAD)-dependent deacetylases expressed in a variety of human somatic cells both in health and disease conditions. The activity and expression of SIRTs affect important metabolic pathways, such as cell survival, senescence, proliferation, energy production, stress tolerance, DNA repair, and apoptosis, thereby closely linked to aging and longevity. Given the broad significance of SIRTs in physiological function maintenance, their activity in somatic cells may reflect the early cross-sectional status of tissue damage caused by aging or systemic inflammatory responses that are too early to be detected by disease-specific biomarkers. In this mini-review, we discuss the utility of SIRTs as a surrogate clinical biomarker for health status to evaluate and monitor health life expectancy and the presence of pre-symptomatic illness states.