Design and biological activity of beta-sheet breaker peptide conjugates.
The sequence LPFFD (iAbeta(5)) prevents amyloid-beta peptide (Abeta) fibrillogenesis and neurotoxicity, hallmarks of Alzheimer's disease (AD), as previously demonstrated. In this study iAbeta(5) was covalently linked to poly(ethylene glycol) (PEG) and the activity of conjugates was assessed and compared to the activity of the peptide alone by in vitro studies. The conjugates were characterized by MALDI-TOF. Competition binding assays established that conjugates retained the ability to bind Abeta with similar strength as iAbeta(5). Transmission electron microscopy analysis showed that iAbeta(5) conjugates inhibited amyloid fibril formation, which is in agreement with binding properties observed for the conjugates towards Abeta. The conjugates were also able to prevent amyloid-induced cell death, as evaluated by activation of caspase 3. These results demonstrated that the biological activity of iAbeta(5) is not affected by the pegylation process.
Rocha
Sandra
S
LEPAE, Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal. sandra.rocha@fe.up.pt
Cardoso
Isabel
I
Börner
Hans
H
Pereira
Maria Carmo
MC
Saraiva
Maria João
MJ
Coelho
Manuel
M
D000544:Alzheimer Disease / Q000378:metabolism*; D000682:Amyloid / Q000187:drug effects* / Q000378:metabolism; D016229:Amyloid beta-Peptides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D015195:Drug Design; D006801:Humans; D046529:Microscopy, Electron, Transmission; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D011092:Polyethylene Glycols / Q000737:chemistry*; D017433:Protein Structure, Secondary / Q000187:drug effects
D000682:Amyloid; D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42); C474023:iAbeta5 peptide; D011092:Polyethylene Glycols