Amyloid-beta induced cell death is independent of free radicals.

Acutely dissociated rat cerebellar granule cell neurons were incubated with amyloid-beta (1-42) and studied by flow cytometry. Amyloid-beta caused a dose-dependent loss of viability, as determined by intracellular accumulation of propidium iodide (PI),and that was not accompanied by significant elevation of intracellular calcium, measured by Fluo-3 or reactive oxygen species (ROS), measured by 2',7'-dihydro-dichlorfluorescein diacetate (DCF). Carnosine, a ROS scavenger and an inhibitor of non-enzymatic glycosylation, partially reduced cell death caused by amyloid-beta.