Title:Molecular Properties of Lysine Dendrimers and their Interactions with Aβ-Peptides and Neuronal Cells
Volume: 20
Issue: 1
Author(s): I.M. Neelov, A. Janaszewska, B. Klajnert, M. Bryszewska, N.Z. Makova, D. Hicks, H.A. Pearson, G.P. Vlasov, M.Yu. Ilyash, D.S. Vasilev, N.M. Dubrovskaya, N.L. Tumanova, I.A. Zhuravin, A.J. Turner and N.N. Nalivaeva
Affiliation:
Keywords:
Amyloidogenesis, amyloid (Aβ) peptide, cell viability, dendrimers, polylysine dendrimers, patch-clamp, computer simulation, toxicity, fluorescence microscopy, vacuolar compartments
Abstract: Prevention of amyloidosis by chemical compounds is a potential therapeutic strategy in Alzheimer’s, prion and other neurodegenerative
diseases. Regularly branched dendrimers and less regular hyperbranched polymers have been suggested as promising inhibitors
of amyloid aggregation. As demonstrated in our previous studies, some widely used dendrimers (PAMAM, PPI) could not only inhibit
amyloid aggregation in solution but also dissolve mature fibrils. In this study we have performed computer simulation of polylysine
dendrimers of 3rd and 5th generations (D3 and D5) and analysed the effect of these dendrimers and some hyperbranched polymers on a
lysine base (HpbK) on aggregation of amyloid peptide in solution. The effects of dendrimers on cell viability and their protective action
against Aβ-induced cytotoxicity and alteration of K+channels was also analysed using human neuroblastoma SH-SY5Y cells. In addition,
using fluorescence microscopy, we analysed uptake of FITC-conjugated D3 by SH-SY5Y cells and its distribution in the brain after intraventricular
injections to rats. Our results demonstrated that dendrimers D3 and D5 inhibited amyloid aggregation in solution while
HpbK enhanced amyloid aggregation. Cell viability and patch-clamp studies have shown that D3 can protect cells against Aβ-induced cytotoxicity
and K+channel modulation. In contrast, HpbK had no protective effect against Aβ. Fluorescence microscopy studies demonstrated
that FITC-D3 accumulates in the vacuolar compartments of the cells and can be detected in various brain structures and populations
of cells after injections to the brain. As such, polylysine dendrimers D3 and D5 can be proposed as compounds for developing antiamyloidogenic
drugs.
