Fluorescence microscopy studies on islet amyloid polypeptide fibrillation at heterogeneous and cellular membrane interfaces and its inhibition by resveratrol

Abstract 

Type II diabetes mellitus (T2DM) is a disease characterized by progressive deposition of amyloid in the extracellular matrix of β-cells. We investigated the interaction of the islet amyloid polypeptide (IAPP) with lipid model raft mixtures and INS-1E cells using fluorescence microscopy techniques. Following preferential partitioning of IAPP into the fluid lipid phase, the membrane suffers irreversible damage and predominantly circularly-shaped lipid-containing IAPP amyloid is formed. Interaction studies with the pancreatic β-cell line INS-1E revealed that growing IAPP fibrils also incorporate substantial amounts of cellular membranes in vivo. Additionally, the inhibitory effect of the red wine compound resveratrol on IAPP fibril formation has been studied, alluding to its potential use in developing therapeutic strategies against T2DM.

Keywords: Amylin, Islet amyloid polypeptide, Type II diabetes mellitus, Amyloid, Giant unilamellar lipid vesicle, Model raft mixture, Fluorescence microscopy, Cytotoxicity