Editorial: The Quest for Biomarkers of Biological Age and Longevity Identifies Roles for Small Noncoding RNAs, Including PIWI-Interacting RNAs

Chronological age plays a major role in medical decision-making but has limitations. Biological aging involves variable changes in cells, tissues, and organs across individuals, potentially affecting molecular processes, including mitochondrial and immune changes, vascular changes, epigenetic drift, and metabolic changes that progress at varying rates. Therefore, reliable biomarkers of biologic age could recalibrate medical decision-making and replace chronologic age in evaluating medical and surgical treatments, transplant evaluation, and cancer screening, which are currently based on chronologic age thresholds that do not account for individual variation. Small noncoding RNAs (sncRNAs) regulate gene expression without coding for proteins and have recently been identified as regulators in aging and longevity. Studies of circulating sncRNAs have identified their potential as biomarkers of biological age. A group of sncRNAs, known as PIWI-interacting RNAs (piRNAs), which play roles in germline genome stability, have recently received attention as potential blood-based biomarkers of biological aging in older adults. This editorial aims to highlight the current status of sncRNAs, including piRNAs, in the ongoing quest for circulating biomarkers of biological age and longevity.