Figure 3.

Additive effects of RA components in amylin amyloid inhibition. (A) ThT fluorescence-based amyloid inhibition assay by RA and its hydrolytic components CA and SAA. Inhibition from a 1:1 molar ratio mixture of CA and SAA is similar to that of RA, but significantly stronger than those from CA or SAA alone. (B) IC₅₀ measurements by ThT fluorescence based inhibition assays. IC₅₀ is estimated to be 200–300 nM for RA, 7.2 μM for CA, and 90 μM for SAA. (C) ThT fluorescence-based amyloid remodeling assay shows amyloid remodeling after spiking of buffer control, RA, CA, SAA, and CA+SAA (1:1 molar ratio) after aggregation reaches a plateau (t = 17 h). (D) Neutralization of amyloid-induced toxicity by RA, CA, and SAA in Neuro2A cells. Amylin concentration was 2.5 μM, and the ratio of the inhibitor/amylin is 5:1. Compared to the control, RA, and to lesser degrees, CA and SAA, significantly neutralize amyloid-induced toxicity. *, p < 0.05; **, p < 0.01.