Feed: Slashdot
Feed Link: https://slashdot.org/
---

Title: Superagers' 'Secret Ingredient' May Be the Growth of New Brain Cells

Link: https://science.slashdot.org/story/26/03/03/0...

alternative_right shares a report from ScienceAlert: According to a study of
38 adult human brains donated to science, superagers -- people who retain
exceptional memory as they age -- have roughly twice as many immature neurons
as their peers who age more typically. Moreover, people with Alzheimer's
disease show a marked reduction in neurogenesis compared to a normal
baseline. [...] Led by researchers at the University of Illinois Chicago, the
team set out to examine a variety of postmortem hippocampal tissue samples to
see if they could identify markers of neurogenesis -- and if different groups
had any notable differences. The brain samples were donated from five groups:
eight healthy young adults, aged between 20 and 40; eight healthy agers, aged
between 60 and 93; six superagers, aged between 86 and 100; six individuals
with preclinical Alzheimer's pathology, aged between 80 and 94; and 10
individuals with an Alzheimer's diagnosis, aged between 70 and 93. The young
healthy adult brain tissue was first analyzed to establish the neurogenesis
pathways in the adult brain. Then, they analyzed 355,997 individual cell
nuclei isolated from the hippocampus, searching for three different stages of
cell development: Stem cells, which can develop into neurons; neuroblasts,
which are stem cells in the process of that development; and immature
neurons, on the verge of functionality. The results were striking.
"Superagers had twice the neurogenesis of the other healthy older adults,"
[says neuroscientist Orly Lazarov of the University of Illinois Chicago].
"Something in their brains enables them to maintain a superior memory. I
believe hippocampal neurogenesis is the secret ingredient, and the data
support that." That's an interesting result on its own, but the data from the
individuals with preclinical Alzheimer's pathology and Alzheimer's diagnoses
is where the real meat of the study sits. In the preclinical group, subtle
molecular changes hinted that the system supporting new neuron growth was
beginning to falter. In the Alzheimer's group, a clear drop in immature
neurons was evident. A genetic analysis of the nuclei also showed that
superager neural cells have increased gene activity linked to stronger
synaptic connections, greater plasticity, and brain-derived neurotrophic
factor, a critical protein for neural survival, growth, and maintenance.
Taken together, these three things can be interpreted as resilience. The
research has been published in the journal Nature.

Read more of this story at Slashdot.

---
VRSS v2.1.180528