Brain cells of ‘superagers’ – humans aged 80 years and over who show exceptional episodic memory at least as good as individuals 20-30 years their junior – may hold the answer to resisting memory and thinking problems later in life, a Northwestern Medicine study has shown.
The study, which was published in the Journal of Neuroscience, involved the analysis of donated superager brains from the Northwestern University Alzheimer’s Disease Research Center (ADRC) Brain Bank.
The brains investigated were split into four groups: six superagers, six younger people with healthy memory and thinking skills, seven age-matched people with average memory and thinking skills, and five people with a type of mild cognitive impairment.
Compared to all other groups in the study – including younger individuals 20-30 years their junior – superagers had ‘significantly larger’ brain cells in their entorhinal cortex, an area of the brain that plays a critical role in memory and thinking abilities.
Superagers also had ‘significantly fewer’ tau tangles characteristic of Alzheimer’s disease, when compared to their cognitively-average same-aged peers.
Taken together, the findings suggest that a neurone spared from tangle formation can maintain its structural integrity, remaining healthy and large.
“The remarkable observation that superagers showed larger neurones than their younger peers may imply that large cells were present from birth and are maintained structurally throughout their lives,” said lead author Tamar Gefen, an assistant professor of psychiatry and behavioural sciences at Northwestern University Feinberg School of Medicine. “We conclude that larger neurones are a biological signature of the superaging trajectory.”
Commenting on the findings of the study, Dr Rosa Sancho, head of research at Alzheimer’s Research UK said: “Problems with memory and thinking skills are early symptoms of Alzheimer’s disease. Understanding more about the areas of the brain responsible for these skills could help develop new treatments.
“… Further research will need to uncover exactly what causes these superager brain cells to be larger and better protected. For example, is it a genetic feature superagers are born with, and if so what features?”
Emily Rogalski, associate director of the Mesulam Center for Cognitive Neurology and Alzheimer’s Disease at Northwestern University Feinberg School of Medicine outlined that the research is expected to be “amplified and more impactful” through a $20m expansion of the superaging initiative now enrolling five sites in the US and Canada.