Why does replicative senescence increase with age in human fibroblasts experiencing chronic low-level oxidative stress?

💡 Explanation

Telomere shortening signals cellular aging because, as telomeres erode with each cell division due to incomplete DNA replication, they eventually trigger a DNA damage response and cell cycle arrest known as replicative senescence. Therefore, cells stop dividing, rather than experiencing histone degradation or efficient DNA repair, both of which would permit continued replication.

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