The Effects of Lipid Membranes, Crowding and Osmolytes on the Aggregation, and Fibrillation Propensity of Human IAPP

Figure 5

Aggregation kinetics of hIAPP in the presence of different membrane models. Time evolution of the amide-I′ bands of 3 μM hIAPP upon aggregation in the presence of a membrane composed of lipids extracted from a pancreatic β-cell line of rat (INS-1E) at 25°C. In (a), primary ATR-FTIR spectra are shown; (b) depicts the concomitant intensity normalized spectra. (c–f) Time evolution of the β-sheet content and adsorption kinetics upon aggregation of hIAPP in the presence of various membrane compositions. (c, e) 10 μM hIAPP at an anionic (DOPC/DOPG, 7 : 3, w/w) membrane, a neutral, zwitterionic DOPC membrane and a neutral heterogeneous lipid raft membrane (DOPC/DPPC/chol, 1 : 2 : 1). (d, f) 3 μM hIAPP in the presence of an anionic heterogeneous lipid raft membrane (DOPC/DOPG/DPPC/DPPG/chol, 15 : 10 : 40 : 10 : 25) and a membrane composed of lipids extracted from the pancreatic β-cell line of rat INS-1E. Adapted and modified from [56, 60] with permission from Elsevier.

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