Primate-specific alterations in neural stem/progenitor cells in the aged hippocampus

Area of Science:

• Neuroscience
• Aging Research
• Stem Cell Biology

Background:

• Neurogenesis, the generation of new neurons from neural stem/progenitor cells (NPCs), occurs in the hippocampus throughout life.
• Aging is associated with a decline in neurogenesis, potentially contributing to age-related cognitive decline.
• Limited research exists on NPC alterations during aging, particularly in primates.

Purpose of the Study:

• To investigate age-related changes in NPCs in the hippocampus of primates.
• To compare NPC alterations in aged primates with those in aged rodents.
• To understand the functional implications of NPC morphological changes during aging.

Main Methods:

• Triple immunostaining for FABP7, Sox2, and GFAP to label NPCs.
• Comparative analysis of NPC numbers and morphology in young and aged macaque monkeys and mice.
• Assessment of NPC proliferation rates in aged monkeys.

Main Results:

• NPC numbers decreased in aged macaque monkeys but not in aged mice.
• Aged macaque monkeys exhibited significant morphological alterations in NPCs, with shorter, horizontally oriented processes.
• NPC proliferation rates remained similar between young and aged macaque monkeys, despite morphological changes.

Conclusions:

• Aging affects NPC numbers and morphology differently in primates compared to rodents.
• Morphological alterations in aged primate NPCs do not impair proliferation but may be crucial for NPC maintenance.
• These findings provide insights into the aging of the primate brain and potential mechanisms underlying cognitive decline.