Human Hippocampal Neurogenesis Persists Throughout the Eighth Decade of Life_Boldrini et al
Adult hippocampal neurogenesis declines in aging rodents and primates. Smaller dentate gyrus (DG), less exercise-induced angiogenesis, and waning neurogenesis, are hypothesized in aging humans. No study has assessed neurogenesis, angiogenesis and DG volume concurrently in autopsy anterior-mid-posterior hippocampus from healthy humans. We show that individuals 14 to 79 years of age have similar numbers of intermediate neural progenitors and immature neurons (thousands) in the DG neurogenic niche, have comparable numbers of glia and mature granule neurons (millions), and equivalent DG volume. Nevertheless, older individuals have less angiogenesis and neuroplasticity, and smaller quiescent progenitor pool, selectively in anterior-mid DG, with no changes in posterior DG. Preserved neurogenesis in healthy older individuals without cognitive impairment, neuropsychiatric disease or treatment, possibly sustains human-specific complex cognitive functions during a long lifespan. Diminishing angiogenesis, neuroplasticity and stem cell pool may account for declining cognitive-emotional resilience, and they might be possible targets to enhance healthy aging.