The effect of curcumin on the stability of Aβ dimers.
Aβ oligomers are potential targets for the diagnosis and therapy of Alzheimer's disease (AD). On the other hand, the molecule curcumin has been shown to possess significant therapeutic potential in many areas. In this paper, we use all-atom explicit solvent molecular dynamics simulations to study the effect of curcumin on the stability of Aβ amyloid protein oligomers. We observed that curcumin decreases the β-sheet secondary structural content within the Aβ oligomers without reducing the contacts between the monomers. The breaking of the β-sheet is found to be preceded by a deformation of the β-sheet structure due to hydrophobic interaction from the nearby curcumin. Furthermore, the π-stacking interaction between curcumin (keto ring and enol ring) and the aromatic residues of Aβ, which exists throughout the simulations, has also contributed to the diminishing of the β-sheet structure. Our analysis of the underwrapped amide-carbonyl hydrogen bonds reveals several stable dehydrons of the oligomer, especially the dehydron pair 34L and 41I, which curcumin tends to hover over. We have examined the paths of curcumin on the Aβ proteins and determined the common routes where curcumin lingers as it traverses around the Aβ. In consequence, our study has provided a detailed interaction picture between curcumin and the Aβ oligomers.
School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore.
Li Na
LN
Zhao
See-Wing
SW
Chiu
Jérôme
J
Benoit
Lock Yue
LY
Chew
Yuguang
Y
Mu
D000544:Alzheimer Disease / Q000188:drug therapy / Q000378:metabolism; D000595:Amino Acid Sequence; D016229:Amyloid beta-Peptides / Q000737:chemistry / Q000378:metabolism*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D003474:Curcumin / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D055503:Protein Multimerization / Q000187:drug effects; D017433:Protein Structure, Secondary / Q000187:drug effects*
D016229:Amyloid beta-Peptides; D000894:Anti-Inflammatory Agents, Non-Steroidal; D000970:Antineoplastic Agents; D003474:Curcumin