CELL-DEATH IN ALZHEIMERS-DISEASE EVALUATED BY DNA FRAGMENTATION IN-SITU

Loss of nerve cells is a hallmark of the pathology of Alzheimer's dise ase (AD), yet the patterns of cell death are unknown. By analyzing DNA fragmentation in situ we found evidence for cell death not only of ne rve cells but also of oligodendrocytes and microglia in AD brains. In average, 30 times more brain cells showed DNA fragmentation in AD as c ompared to age-matched controls. Nuclear alterations suggestive of apo ptosis were rare in degenerating cells. Even though the majority of de generating cells were not located within amyloid deposits and did not contain neurofibrillary tangles, neurons situated within areas of amyl oid deposits or affected by neurofibrillary degeneration revealed a hi gher risk of DNA fragmentation and death than cells not exposed to the se AD changes.