amyloid-beta-peptides and Liver-Neoplasms

Herein we describe the inhibitory effect of the synthetic peptide Abeta1-40, homologous to the major high-density lipoprotein-associated species of Alzheimer's amyloid beta protein (Abeta), on lipid biosynthesis in human hepatic HepG2 cells. This culture synthesizes various lipids from [14C]acetate as a precursor. Treatment of cells with different concentrations of Abeta1-40 decreased the syntheses of various radiolabeled lipid species. The decrease reached saturation at peptide concentrations equal to 10-100 ng ml(-1). The lipids whose synthesis was decreased most were free and esterified cholesterol and phospholipids. This inhibitory effect suggests that Abeta protein may modulate physiological intracellular lipid syntheses. It may also be of special importance in the pathological condition, and contribute to the neurodegeneration, in Alzheimer's disease and related disorders.

Topics: Acetates; Amyloid beta-Peptides; Carcinoma, Hepatocellular; Cell Line; Cholesterol; Dose-Response Relationship, Drug; Humans; Kinetics; Lipids; Liver Neoplasms; Peptide Fragments; Phospholipids; Tumor Cells, Cultured