Chronic high fat cholesterol diet
in rats exhibit pathologies similar to Alzheimer’s disease, a new study by Laboratory of Psychiatry and Experimental Alzheimers Research at the Medical University Innsbruck (Austria) has demonstrated.
The major pathological hallmarks of Alzheimer’s disease are extracellular aggregates (plaques)
of the small peptide beta-amyloid, hyperphosphorylation of the protein tau and subsequent formation of intracellular neurofibrillary tangles, degeneration of neurons secreting the neurotransmitter acetylcholine, inflammation, and cerebrovascular dysfunction.
The causes for Alzheimer’s disease are not known, but dysregulation of amyloid-precursor protein expression and beta-amyloid clearance is hypothesized (beta-amyloid cascade). Alternatively, a pathological cascade of events may trigger hyper-phosphorylation of tau, putting the tau-hypothesis into the center. A third hypothesis suggests that chronic long-lasting mild cerebrovascular damage, including inflammatory processes and oxidative stress, may cause Alzheimer’s disease. It has been suggested that Alzheimer’s disease starts 20-30 years before first symptoms appear and recent studies have shown, that high cholesterol levels are linked to the pathology of this disease.