Aging Biomarkers: From Functional Tests to Multi-Omics Approaches.

Aging results in various deleterious changes in the human body that may lead to loss of function and the manifestation of chronic diseases. While diseases can generally be reliably diagnosed, the aging process itself requires more sophisticated approaches to evaluate its progression. Numerous attempts have been made to establish biomarkers to quantify human aging at the cellular, tissue, and organismal level. Here, an up-to-date overview of biomarkers related to human aging with an emphasis on biomarkers that take into account different mechanisms of aging between individuals is provided. Classical discrete molecular and non-molecular biomarkers handpicked by researches on the base of their strong correlation with age, as well as emerging omics-based biomarkers, are discussed and potential future directions and developments in the field of aging assessment are outlined.