Genomic instability caused by DNA damage • Attrition of the protective chromosomal endcaps, the telomeres • Alterations to the epigenome that controls which genes are turned on and off • Loss of healthy protein maintenance, known as proteostasis • Deregulated nutrient sensing caused by metabolic changes • Mitochondrial dysfunction • Accumulation of senescent zombielike cells that inflame healthy cells • Exhaustion of stem cells • Altered intercellular communication and the production of inflammatory molecules

