Influence of Aluminium and EGCG on Fibrillation and Aggregation of Human Islet Amyloid Polypeptide

Figure 5

The influence of Al(III) on the fibrillation and aggregation of hIAPP. (a) Kinetics of 16 μM hIAPP fibrillation with 0 (■), 2 (●), 8 (▲), and 64 (▼) μM Al(III) in 20 mM PBS at pH 7.4 under 37°C, monitored by ThT fluorescence. The values represent mean (). Solid lines represent the curves fitted using (1). (b) TEM image of 16 μM hIAPP incubated in 20 mM PBS with 2 μM Al(III) for 2 h. (c) Contour plots of ¹H NMR spectra within chemical shift from 7.13 to 7.3 ppm for 100 μM hIAPP incubated in 6 mM PBS at pH 7.4 and 25°C on incubation time with 12.5 μM Al(III). (d) Aggregation kinetics of integrated resonance intensity of ¹H NMR spectra from 7.13 to 7.3 ppm of 100 μM hIAPP without (■) and with (●) 12.5 μM Al(III). Solid lines represent the curves fitted using (1). The integration values were normalized to the initial hIAPP alone data.

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