NR AWDP
AU Corsaro,A.; Villa,V.; Thellung,S.; Raggi,F.; Chiovitti,K.; Paludi,D.; Aceto,A.; Florio,T.
TI Evaluation of potential anti-prion drugs using the neurotoxic HPrp90-231 prion protein fragment (miniprion, rmp)
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions CE-07
PT Konferenz-Poster
AB In vitro and in vivo studies have been performed to identify the molecular determinant of the neuronal death induced by full-length PrPsc or PrP-derived peptides. We developed a completely new experimental model to assess PrPsc neurotoxicity, using the recombinant PrP-related polypeptide, encompassing the amino acid 90-231 of the human PrP sequence (rMP) that corresponds to the protease-resistant core of PrPsc. This study was aimed to evaluate the role of PrP structural configuration in prion-dependent neurotoxicity and to identify drugs able to interfere with the neurodegenerative pathways. Using a controlled thermal denaturation protocol, we set up an experimental model to convert rMP from a PrPc like into a PrPsc like conformation. Thermal denaturation converted rMP into an isoform characterized by high content of ß-sheet structures and partially resistant to Pk treatment. In virtue of these structural changes, rMP powerfully affected the survival of SH-SY5Y cells, inducing a caspase-3 and p38 dependent apoptosis. Conversely, in the native -helix-rich conformation, rMP did not show a significant cell toxicity. Thus we report a precise correlation between the toxicity of rMP and its three-dimensional structure. In order to identify drugs able to interfere with rMP toxicity, we determined the efficacy and the putative molecular mechanisms of minocycline (M) a second-generation tetracycline, and quinacrine (Q) a heterocyclic acridine derivatives compound, in inhibiting cell death induced by rMP in SH-SY5Y cells. We demonstrate that both Q and M are able to revert the rMP-induced toxicity. We identified two distinct mechanisms activated by these drugs: Q exerts its protective action by binding with rMP and preventing the formation of the rich toxic isoform, while M reverts the activation of p38, and the inhibition of ERK1/2 and AKT, induced by rMP. In conclusion we demonstrate, using rMP model, that quinacrine and minocycline are compounds able to block rMP neurotoxic effects, and we identify their possible cellular mechanisms of action. (Grant by PRIN 2004 to TF).
AD A. Corsaro, V. Villa, S. Thellung, F. Raggi: Dept. Oncology Biology and Genetics, Section of Pharmacology, University of Genova, Italy; K. Chiovitti, D. Paludi, A. Aceto, T. Florio: Dept. Biomedical Sciences, Section of Biochemistry, University G.D'Annunzio, Chieti, Italy. E-mail: Ale.Corsaro@unige.it
SP englisch
PO Italien