Structures in brain may help in understanding Alzheimer's

Differences in Alzheimer's patients' brains may help researchers learn why the disease progresses at different rates and different severity, a study suggested. Robert Tycko, senior investigator at the U.S. National Institutes of Health and lead author of the study published Thursday in the journal Cell, said research into plaque-forming structures of the brain -- called beta-amyloid fibrils -- could help in the development of new imaging agents that might advance diagnosis, HealthDay News reported. "Variations in disease may have a structural basis and be due to differences in the molecular structure of the fibrils," Tycko said. Terrence Town, professor of physiology and biophysics at the Keck School of Medicine at the University of Southern California in Los Angeles, said the study's finding is "a huge step forward." "They have accomplished something we have been trying to do for a decade," said Town, who was not involved in the study. Researchers in the study used tissue from the brains of two deceased patients who exhibited different symptoms of Alzheimer's and used it to grow beta-amyloid fibrils -- which have been linked to Alzheimer's, Parkinson's disease, Atherosclerosis, diabetes and other diseases. They used nuclear magnetic resonance and electron microscopy to visualize the beta-amyloid fibrils in brain tissue and found there are "at least two different varieties [of amyloid structure] in Alzheimer's disease." "And certain fibril structures may be more likely than others to cause the disease," Tycko said. However, he said the researchers did not establish correlations between molecular structure and variations in disease, HealthDay News reported.