Older adults can generate as many brain cells as young people
Researchers may have finally solved the mystery of whether or not adults grow new brain cells. For the first time, experts have demonstrated that healthy older adults can generate just as many neurons as young people.
Lead author Maura Boldrini is an associate professor of Neurobiology at Columbia University. She explained that the findings of this research suggest that some elderly adults are much less cognitively and emotionally impaired than previously thought.
“We found that older people have similar ability to make thousands of hippocampal new neurons from progenitor cells as younger people do,” said Professor Boldrini.
“We also found equivalent volumes of the hippocampus (a brain structure used for emotion and cognition) across ages. Nevertheless, older individuals had less vascularization and maybe less ability of new neurons to make connections.”
The study was focused on the hippocampal brain region of individuals who died suddenly between the ages of 14 and 79. The researchers examined newly-formed neurons as well as the condition of blood vessels throughout the entire hippocampus shortly after death.
The research team had previously concluded that depression or antidepressants can negatively impact the production of new brain cells. The study subjects had not been impacted by depression or cognitive impairment
The investigation revealed that even the oldest brains had recently produced new brain cells. “We found similar numbers of intermediate neural progenitors and thousands of immature neurons,” wrote the study authors.
On the other hand, older individuals had formed fewer new blood vessels within brain structures and possessed a smaller pool of progenitor cells, which are similar to stem cells in that they can differentiate to form one or more kinds of cells.
The results of the study indicate that reduced cognitive – emotional resilience in older adults may be caused by fewer progenitor cells combined with reduced vascularization and cell-to-cell connectivity within the hippocampus.
“It is possible that ongoing hippocampal neurogenesis sustains human-specific cognitive function throughout life and that declines may be linked to compromised cognitive-emotional resilience,” said Professor Boldrini.
Further research is needed to understand how neural cell proliferation and survival are regulated by hormones and other inter-cellular pathways in aging adults, according to Professor Boldrini.
The study is published in the journal Cell Stem Cell.