Senescent cells accumulate lipid droplets as the brain ages

The accumulation of lipid droplets in brain cells marks a hallmark of neurological aging and neurodegenerative disease, and new research identifies senescent cells as the source. These growth-arrested cells remain metabolically active and undergo extensive reprogramming to fuel chronic inflammation through their senescence-associated secretory phenotype. In human fibroblast models and in Alzheimer's disease brains, senescent microglia showed elevated lipid droplet markers, with metabolic profiling revealing elevated glycolytic metabolites alongside triacylglycerol derivatives—the precursors of lipid droplets. Single-nucleus analysis of postmortem Alzheimer's tissue confirmed this co-occurrence across multiple senescent cell types, including microglia. For longevity-focused readers, this convergence suggests that senolytic therapies targeting cellular senescence might simultaneously resolve lipid dysfunction and microglial inflammation, addressing a root cause rather than a symptom of cognitive aging.