β-amyloid peptides induce degeneration of cultured rat microglia

Microglia are often associated with senile plaques, a primary pathological hallmark of Alzheimer's disease (AD) that consists largely of insoluble deposits of β-amyloid (Aβ) protein. Synthetic Aβ peptides have been shown to induce neurite dystrophy and neuronal death in vitro when the peptides are assembled into aggregates. We now report that assembled Aβ peptides induce morphological evidence of degeneration in process-bearing microglia in vitro, as well as metabolic dysfunction in microglial cultures, but a non-assembling scrambled sequence Aβ peptide does not.