Aging
Aging Biomarkers in Osteoporosis: A Review of Molecular Mechanisms, Biological Aging, and Population Evidence Miaosen Liu* Miaosen Liu Liu Liu National University of Singapore
Osteoporosis is a common age-related skeletal disease that is identified by low bone mass and bone deterioration, which leads to higher risks of fracture and disability. While chronological age is an important predicting factor for osteoporosis, biological aging scale may be able to capture nuance in systemic and bone-tissue aging among individuals with the same age. This review summarizes how DNA methylation and telomere dysfunction (mainly telomere shortening) are associated with bone health and cellular aging. We then describe the concepts of DNA-methylation based aging clocks and leucocyte telomere length (LTL) as blood-derived biomarkers for biological aging and their relationship with bone health and osteoporosis by systematically reviewing past studies. This review concludes that while studies in laboratory-based aging markers often provide evidence on their association with bone outcomes, population-level epidemiological studies provide unconcluded pictures, highlighting limited studies on epigenetic aging clocks with bone health and inconsistency in results from studies of an association with LTL. Common challenges many of the selected human studies faced include small sample sizes, inadequate study designs, non-diverse cohorts, and heterogeneity in epigenetic clock choices and/or bone health outcomes. Future research should be focused on conducting prospective studies with larger, independent cohort sizes with comprehensive adjustment of intervening factors in order to achieve overall consensus on that bone health issue, paint a clearer picture of the biological aging markers’ associations with bone health, and ultimately, provide guidance on their potential use in clinical settings in bone health promotion.