Table 1.
Potential Biomarkers of the Hallmarks of Aging (courtesy of Tamara Tchkonia and Nathan LeBrasseur)
| Hallmark | Biomarker Measures | Biological Matrix |
|---|---|---|
| Mitochondrial dysfunction | Mitochondrial function/respiration | PBMCs |
| Mitochondrial volume, number, shape | Tissue biopsy | |
| Markers of biogenesis | mtDNA | |
| mtDNA copy number, mutations, haplotypes | ||
| NAD+ metabolites | ||
| Sirtuins | ||
| Loss of proteostasis | Autophagy markers and flux | Blood |
| Chaperone proteins | Tissue biopsy | |
| Advanced glycation end products (AGEs) | Live cells | |
| Protein aggregates | CSF | |
| Stem cell dysfunction | Replication/differentiation potential | Blood |
| Tissue regeneration | Tissue biopsy Live cells | |
| Nutrient sensing | IGF-1 pathway | Blood |
| mTOR signaling | Tissue biopsy | |
| Genomic Instability | Single-cell/NGS, SNP analyses | Blood |
| DNA repair | PBMCs | |
| Measures of DNA modifications | Tissue biopsy | |
| Long interspersed nuclear elements (LINEs) | Live cells | |
| Reverse transcriptase | ||
| Telomere dysfunction | Telomere length | Blood |
| Markers of DNA damage response | PBMCs | |
| Telomerase activity | Tissue biopsy | |
| Telomere-associated foci | ||
| Cellular senescence | p16, p21, p53 | Blood |
| Histological marks (SABG, TAFs, SADs) | PBMCs | |
| SASP products, miRNA, circulating mtDNA | Tissue biopsy | |
| Extracellular vesicles and microvesicles | CSF | |
| Circulating p16Ink4A + CD3+ T cells | Urine | |
| Epigenetic changes | Methylation | Blood |
| Histone acetylation | PBMCs | |
| Non-coding RNAs | Tissue biopsy Swab |