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Research from the Laboratory of Psychiatry and ExperimentalAlzheimers Research at the Medical University Innsbruck (Austria)demonstrated that chronic high fat cholesterol diet in rats exhibited pathologies similar to Alzheimer's disease . The results were published in Molecular Cellular Neuroscience(45(4):408-417, 2010) with lead author Dr. Christian Humpel. Thestudy was co-authored by PhD students, Celine Ullrich and MichaelPirchl, from the same Laboratory. Alzheimer's disease is a severe neurodegenerative disorder of thebrain that is characterized by loss of memory and cognitivedecline. The majority of Alzheimer's disease cases are sporadic(risk age 60 years), and only 2.5% have a geneticdisposition. It is estimated that in 2050, approximately 80 millionpeople will suffer from Alzheimer's disease worldwide. The majorpathological hallmarks of Alzheimer's disease are extracellularaggregates (plaques) of the small peptide beta-amyloid,hyperphosphorylation of the protein tau and subsequent formation ofintracellular neurofibrillary tangles, degeneration of neuronssecreting the neurotransmitter acetylcholine, inflammation, andcerebrovascular dysfunction. The causes for Alzheimer's disease are not known, but dysregulationof amyloid-precursor protein expression and beta-amyloid clearanceis hypothesized (beta-amyloid cascade). Alternatively, apathological cascade of events may trigger hyper-phosphorylation oftau, putting the tau-hypothesis into the center. A third hypothesissuggests that chronic long-lasting mild cerebrovascular damage,including inflammatory processes and oxidative stress , may cause Alzheimer's disease. It has been suggested thatAlzheimer's disease starts 20-30 years before first symptoms appearand recent studies have shown, that high cholesterol levels arelinked to the pathology of this disease. The aim of the study led by Humpel was to study the effects ofhypercholesterolemia in adult rats. Male 6 months old SpragueDawley rats were fed with normal food (controls) or with a special5% cholesterol-enriched diet (hypercholesterolemia). After 5 monthsanimals were tested for behavioral impairments and pathologicalmarkers similar to those found in the brains of patients withAlzheimer's disease. The results showed that chronichypercholesterolemia caused memory impairment, cholinergicdysfunction, inflammation, enhanced cortical beta-amyloid and tauand induced microbleedings, all indications, which resemble anAlzheimer's disease-like pathology. Thus the data are in line with earlier studies showing that highfat lipids, including cholesterol, may participate in thedevelopment of sporadic Alzheimer's disease. However, sinceAlzheimer's disease is a complex heterogenous disease, these datado not allow the conclusion that cholesterol alone is responsiblefor the disease. It can be speculated that chronic mildcerebrovascular damage caused and potentiated by different vascularrisk factors (including cholesterol) may contribute to thesepathologies. It needs to be determined in future studies how mildchronic microvascular bleedings, silent strokes and mild blood-brain barrier damage over decades may play a rolein the development of this disease. Indeed several data (Ladecola,Nat.Rev.Neurosci. 5, 347-360, 2004) support the view thatAlzheimer's disease can be considered as a vascular disease andthat a dysfunctional clearance of beta-amyloid from brain to bloodand vice versa may be a secondary important step in the cascade ofinitiation of the disease. Sources: Elsevier, AlphaGalileo Foundation . Additional References Citations. I am an expert from slimming-machines.com, while we provides the quality product, such as Body Slimming Machine Manufacturer , China Portable Spa Equipment, RF Slimming Machine,and more.
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