PEGylated β-Sheet Breaker Peptides as Inhibitors of β-Amyloid Fibrillization

Three PEGylated beta-sheet breaker peptides are designed as new inhibitors of beta-amyloid fibrillization. The peptide Ac-Leu-Pro-Phe-Phe-Asp-NH2, considered the lead compound, and hexamers in which taurine and beta-alanine substitute the acetyl group, are conjugated to poly(ethylene glycol); this conjugates self-assemble into nanoparticles. The activity of the PEGylated peptides as inhibitors of amyloid fibrillization are tested in vitro using circular dichroism spectroscopy and scanning electron microscopy. The experimental results indicate that PEGylation does not impair the ability of the beta-sheet breaker peptides to inhibit fibrillogenesis in vitro. Moreover, microscopy images of beta-amyloid incubated for 6 days with the taurine-containing peptide, suggest that this conjugate has major anti-fibrillogenesis activity and demonstrate the important role of the sulfonamide function against the amyloid aggregation.