Alzheimer's disease is a severe
neurodegenerative disease characterized by the aggregation of
amyloid-β
peptide (Aβ) into toxic oligomers which activate microglia and astrocytes causing acute
neuroinflammation. Multiple studies show that the soluble oligomers of Aβ42 are neurotoxic and proinflammatory, whereas the monomers and insoluble fibrils are relatively nontoxic. We show that Aβ42 aggregation is inhibited in vitro by
oil palm phenolics (
OPP), an aqueous extract from the
oil palm tree (Elaeis guineensis). The data shows that
OPP inhibits stacking of β-pleated sheets, which is essential for oligomerization. We demonstrate the inhibition of Aβ42 aggregation by (1) mass spectrometry; (2)
Congo Red dye binding; (3) 2D-IR spectroscopy; (4) dynamic light scattering; (5) transmission electron microscopy; and (6) transgenic yeast rescue assay. In the yeast rescue assay,
OPP significantly reduces the cytotoxicity of aggregating
neuropeptides in yeast genetically engineered to overexpress these
peptides. The data shows that
OPP inhibits (1) the aggregation of Aβ into oligomers; (2) stacking of β-pleated sheets; and (3) fibrillar growth and coalescence. These inhibitory effects prevent the formation of neurotoxic oligomers and hold potential as a means to reduce
neuroinflammation and neuronal death and thereby may play some role in the prevention or treatment of
Alzheimer's disease.