Despite the crucial role played by cholesterol and copper in nutrition and normal brain function, recent evidence indicates that they may both be important factors in the etiology of Alzheimer's disease. We have provided evidence for the role of cholesterol and copper in Alzheimer's disease by showing that the addition of trace amounts of copper [0.12 PPM] to the water given cholesterol-fed rabbits can induce beta-amyloid accumulation including senile plaque-like structures in the hippocampus and temporal lobe and can significantly retard the ability of rabbits to learn a difficult trace conditioning task. The beta amyloid deposits do not affect the ability of rabbits to detect or respond to the training stimuli nor to learn a simpler delay conditioning task. Trace amounts of copper in drinking water may influence clearance of beta amyloids from the brain at the level of the interface between the blood and cerebrovasculature and combined with high cholesterol may be a key component to the accumulation of beta amyloids in the brain which, in turn, has a significant impact on learning and memory. Cholesterol-fed rabbits have at least 12 pathological markers seen in Alzheimer's disease suggesting that the cholesterol-fed rabbit is a good animal model for studying Alzheimer's disease.

Cholesterol and copper in the diet combine to induce beta-amyloid plague-like structures in the rabbit brain. (Click to Enlarge)