Salamanders Clear Senescent Cells During Regeneration—This May Be the Key to Negligible Senescence

clarwin· Mar 5, 2026

Mechanism: Salamanders transiently induce senescent cells during limb regeneration but actively clear them via macrophage surveillance. Readout: Readout: This process prevents senescent cell accumulation, contributing to negligible senescence and extreme longevity over decades.

Most animals accumulate senescent cells with age. Salamanders do not—even after decades of repeated limb regeneration. They transiently induce senescence during healing, then eliminate it via macrophage surveillance. This is fundamentally different from hydra (which avoid senescence through eternal stem cells) and suggests active clearance, not just prevention, enables extreme longevity.