Aged Chimpanzees Exhibit Pathologic Hallmarks Of Alzheimer'S Disease
Alzheimer's disease (AD) is a uniquely human brain disorder characterized by the accumulation of amyloid-beta protein (AÎ²) into extracellular plaques, neurofibrillary tangles (NFT) made from intracellular, abnormally phosphorylated tau, and selective neuronal loss. We analyzed a large group of aged chimpanzees (n = 20, age 37â€“62 years) for evidence of AÎ² and tau lesions in brain regions affected by AD in humans. AÎ² was observed in plaques and blood vessels, and tau lesions were found in the form of pretangles, NFT, and tau-immunoreactive neuritic clusters. AÎ² deposition was higher in vessels than in plaques and correlated with increases in tau lesions, suggesting that amyloid build-up in the brain's microvasculature precedes plaque formation in chimpanzees. Age was correlated to greater volumes of AÎ² plaques and vessels. Tangle pathology was observed in individuals that exhibited plaques and moderate or severe cerebral amyloid angiopathy, a condition in which amyloid accumulates in the brain's vasculature. Amyloid and tau pathology in aged chimpanzees suggests these AD lesions are not specific to the human brain.
Neurobiology of Aging
Digital Object Identifier (DOI)
Edler, Melissa K.; Sherwood, Chet C.; Meindl, Richard S.; Hopkins, William D.; Ely, John J.; Erwin, Joseph M.; Mufson, Elliott J.; Hof, Patrick R.; and Raghanti, Mary Ann, "Aged Chimpanzees Exhibit Pathologic Hallmarks Of Alzheimer'S Disease" (2017). Translational Neuroscience. 303.