A histopathological study on senile changes in the human olfactory bulb.

Area of Science:

• Neurology
• Histopathology
• Aging Research

Background:

• Senile changes, including neurofibrillary tangles (NFTs) and senile plaques (SPs), are characteristic of aging brains.
• The olfactory bulb's role in aging and neurodegenerative diseases is an area of ongoing investigation.

Purpose of the Study:

• To histopathologically examine senile changes in the human olfactory bulb.
• To determine the frequency and age-related prevalence of NFTs and SPs in the olfactory bulb.
• To compare the occurrence of senile changes in the olfactory bulb with those in the hippocampus and parahippocampal gyrus.

Main Methods:

• Histopathological analysis of olfactory bulb tissue from 133 individuals aged 40-91 years.
• Quantification and age-stratified analysis of neurofibrillary tangles (NFTs) and senile plaques (SPs).
• Examination of senile changes in the hippocampus and parahippocampal gyrus for comparative analysis.

Main Results:

• Neurofibrillary tangles (NFTs) were observed in 35.3% of all subjects and 40.5% of those aged 50 and older, increasing linearly with age.
• Senile plaques (SPs) were found in 3.8% of all subjects and 5.7% of those aged 60 and older.
• Granulovacuolar degeneration was rare; amyloid angiopathy was not detected. Frequencies of NFTs and SPs varied between the olfactory bulb and hippocampal regions.

Conclusions:

• Senile changes, particularly NFTs, are prevalent in the aging human olfactory bulb.
• The frequency of NFTs in the olfactory bulb shows a positive linear correlation with age.
• The study did not definitively establish whether senile changes originate in the olfactory bulb or the hippocampal region.