HISTOCHEMICAL DETECTION OF 4-HYDROXYNONENAL PROTEIN IN ALZHEIMER AMYLOID

The presence of lipid peroxidation product in amyloid deposits from se ven patients with Alzheimer disease and nine with non-Alzheimer diseas e was examined immunohistochemically by means of an affinity purified anti-HNE antibody to hydroxynonenal (HNE), a marker of lipid peroxidat ion. A positive reaction was found in amyloid deposits in ail the spec imens examined: mast of the perivascular areas (89%) where amyloid dep osition was confirmed by Congo red staining, showed immunoreactivity w ith the antibody in the specimens of Alzheimer disease. Twenty-one per cent of senile plaques which were also stained by Congo red staining r eacted with this antibody. Several perivascular cells were also staine d by anti-HNE antibody. In other neurons both in Alzheimer and non-Alz heimer disease patients, only a few percent reacted with this antibody and no statistical difference was observed between them. These result s verify that lipid peroxidation via free radical injury occurs in amy loid deposits in Alzheimer amyloid. Since HNE has been identified as a cytotoxic metabolite of free radical injury, amyloid deposits in the tissue may exhibit a toxic effect during the generation process of HNE . (C) 1998 Elsevier Science B.V.