Naked mole rat cells are protected from cellular senescence via Wnt/β-catenin-promoted cholesterol metabolism

The naked mole rat (NMR; Heterocephalus glaber) exhibits cancer resistance and an exceptionally long lifespan of approximately 30 years. The longevity of the NMR is widely debated, as it poses challenges to theories associated with aging, cancer, and redox homeostasis. In the present study, we report unique mechanisms of cholesterol metabolism in NMR cells that could be responsible in part for their anti-senescent properties. We found that NMR fibroblasts abundantly express β-catenin, and that increased β-catenin activity is linked to increased accumulation of cholesterol-enriched lipid droplets. Either β-catenin knockdown or inhibition of cholesterol synthesis abolished lipid droplet formation, and enhanced induction of senescence-like phenotypes. Analysis of β-catenin-regulated genes revealed that β-catenin upregulated the LXR/RXR pathway and Apolipoprotein F, which are involved in cholesterol biogenesis and transport. Specifically, Apolipoprotein F is involved in the accumulation of lipid droplets, protecting NMR cells from cellular senescence. We thus suggest that increased β-catenin activity evolved in NMRs to offset senescence via the accumulation of cholesterol-enriched lipid droplets. Hence, the anti-senescence effects of the Wnt/β-catenin signaling in NMRs reveals new strategies for the development of anti-cancer and anti-aging treatments.