title: Aβ(42) induced MRI changes in aged rabbit brain resembles AD brain.
abstract: Alzheimer's disease is the most common form of dementia and is structurally characterized by brain atrophy and loss of brain volume. Aβ is one of the widely accepted causative factors of AD. Aβ deposition is positively correlated with brain atrophy in AD. In the present study, structural brain imaging techniques such as Magnetic Resonance Imaging (MRI) were used to measure neuroanatomical alterations in Alzheimer's disease brain. MRI is a non-invasive method to study brain structure. The objective of the present study was to elucidate the role of Aβ on brain structure in the aged rabbit brain. Among 20 aged rabbits, one batch (n=10) rabbits was injected chronically with Aβ(1-42) and another batch (n=10) with saline. The MRI was conducted before Aβ(1-42)/saline injection and after 45 days of Aβ(1-42)/saline injection. All the aged rabbits underwent MRI analysis and were euthanized after 45 days. The MRI results showed a significant reduction in thickness of frontal lobe, hippocampus, midbrain, temporal lobe and increases in the lateral ventricle volume. We also conducted an MRI study on AD (n=10) and normal (n=10) cases and analyzed for the thicknesses of frontal lobe, hippocampus, midbrain, temporal lobe and lateral ventricle lobe. We found significant reductions in thickness of the frontal lobe and the hippocampus. However, no significant reduction in the thickness of midbrain, temporal lobe or increase in the lateral ventricle volume was observed compared to normal. Correlations in brain atrophy changes between rabbit brain and human AD brain were found for frontal lobe and hippocampal regions. In contrast, other regions such as midbrain, temporal lobe, and lateral ventricles were not correlated with rabbit brain atrophy changes in the corresponding regions. The relevance of these changes in AD is discussed.
authors: Department of Biochemistry and Nutrition, CFTRI, Mysore, India.
authors: B N
authors: BN
authors: Ramesh
authors: K P
authors: KP
authors: Raichurkar
authors: N M
authors: NM
authors: Shamasundar
authors: T S S
authors: TS
authors: Rao
authors: K S J
authors: KS
authors: Rao
mesh_terms: D000375:Aging / Q000473:pathology*; D000544:Alzheimer Disease / Q000473:pathology*; D016229:Amyloid beta-Peptides / Q000633:toxicity*; D000818:Animals; D001284:Atrophy; D001921:Brain / Q000254:growth & development / Q000473:pathology*; D005260:Female; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010446:Peptide Fragments / Q000633:toxicity*; D011817:Rabbits
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)