Olive Component Oleuropein Promotes ß-Cell Insulin Secretion and Protects ß-Cells from Amylin Amyloid-Induced Cytotoxicity.

ABSTRACT

Oleuropein, a natural product derived from olive leaves, has reported anti-diabetic functions. However, detailed molecular mechanisms for how it affects ß-cell functions remain poorly understood. Here, we present evidence that oleuropein promotes glucose-stimulated insulin secretion (GSIS) in ß-cells. The effect is dose-dependent and stimulates the ERK/MAPK signaling pathway. We further demonstrated that oleuropein inhibits the cytotoxicity induced by amylin amyloids, a hallmark feature of type 2 diabetes. We demonstrated that these dual functions are structure-specific we identified the 3-hydroxytyrosol moiety of oleuropein as the main functional entity responsible for amyloid inhibition, but the novel GSIS function requires the entire structure scaffold of the molecule.