Neuronal binucleation in Alzheimer disease hippocampus.

Area of Science:

• Neuroscience
• Cell Biology
• Pathology

Background:

• Adult brain neurons are typically considered fully differentiated and non-dividing.
• Alzheimer disease (AD) neurons exhibit an activated cell cycle phenotype, challenging this dogma.
• The extent of neuronal cell cycle progression, including nuclear division, in AD remains unclear.

Purpose of the Study:

• To investigate whether nuclear division occurs in neurons affected by Alzheimer disease.
• To determine if neurons in AD brains can complete cell cycle progression leading to nuclear division.

Main Methods:

• Examination of 101 post-mortem hippocampal tissue sections from Alzheimer disease and control cases.
• Histopathological evaluation for the presence of neuronal binucleation using routine staining.

Main Results:

• Binucleated neurons were identified in the hippocampus of Alzheimer disease cases.
• No binucleated neurons were observed in control cases (P < 0.05).

Conclusions:

• The presence of binucleated neurons in AD brains provides morphological evidence of nuclear division.
• This finding supports the hypothesis that neurons in the adult human brain can re-enter a coordinated cell cycle in Alzheimer disease.
• Neuronal binucleation is a rare event in AD, occurring approximately once per 20,000 neurons.