Title : Gender and Age Effects on Amyloid Plaque Deposition in a Rat Alzheimer’s Disease Model
Abstract:
Background: Alzheimer’s Disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid beta (Aβ) plaques and neurofibrillary tangles in the hippocampus and cerebral cortex of the brain. This may result in cognitive impairment, inflammation, and neurological damage to the brain. Understanding how age and sex affect the quantity of plaque can provide insight into AD pathogenesis. This study examines the age progression of Aβ plaque deposition in male and female transgenic (AD model) and non-transgenic (control) rats using Congo Red Staining. The purpose of this study is to determine how age and sex influence plaque distribution and density in specific regions of the brain.
Methods: Rat brain sections (10 μm thick) were obtained from transgenic and non-transgenic male and female rats at 6, 16, and 20 months old. Congo Red staining, a histological method that binds to β-pleated sheets structures found in amyloid plaques, was used to expose amyloid plaques in the brain. Then, a fluorescence microscope was used to examine and document plaque distribution in rat brain sections, and quantitative analysis of plaque area and density was carried out using the ImageJ software.
Results: In transgenic rats, plaque accumulation increased significantly in the hippocampus and cortex from ages 6 months to 20 months of age. Additionally, female transgenic rats exhibited greater plaque accumulation than males across most age groups. Conversely, non-transgenic rats showed little to no plaque deposition across all age and sex groups.
Conclusion: The study shows that sex and age significantly impact Aβ plaque accumulation in transgenic rats. Female rats showed greater plaque than males at older ages, suggesting genetics may influence the progression and severity of Alzheimer’s Disease. These findings highlight sex and age as important variables in Alzheimer’s research.
