title: Persistent dystrophin protein restoration 90 days after a course of intraperitoneally administered naked 2'OMePS AON and ZM2 NP-AON complexes in mdx mice.
abstract: In Duchenne muscular dystrophy, the exon-skipping approach has obtained proof of concept in animal models, myogenic cell cultures, and following local and systemic administration in Duchenne patients. Indeed, we have previously demonstrated that low doses (7.5 mg/Kg/week) of 2'-O-methyl-phosphorothioate antisense oligoribonucleotides (AONs) adsorbed onto ZM2 nanoparticles provoke widespread dystrophin restoration 7 days after intraperitoneal treatment in mdx mice. In this study, we went on to test whether this dystrophin restoration was still measurable 90 days from the end of the same treatment. Interestingly, we found that both western blot and immunohistochemical analysis (up to 7% positive fibres) were still able to detect dystrophin protein in the skeletal muscles of ZM2-AON-treated mice at this time, and the level of exon-23 skipping could still be assessed by RT real-time PCR (up to 10% of skipping percentage). In contrast, the protein was undetectable by western blot analysis in the skeletal muscles of mdx mice treated with an identical dose of naked AON, and the percentage of dystrophin-positive fibres and exon-23 skipping were reminiscent of those of untreated mdx mice. Our data therefore demonstrate the long-term residual efficacy of this systemic low-dose treatment and confirm the protective effect nanoparticles exert on AON molecules.
authors.affiliation: Department of Experimental and Diagnostic Medicine, Section of Medical Genetics, University of Ferrara, Via Fossato di Mortara 74, 44100 Ferrara, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Bassi
authors.forename: Sofia
authors.initials: S
authors.lastname: Falzarano
authors.forename: Marina
authors.initials: M
authors.lastname: Fabris
authors.forename: Francesca
authors.initials: F
authors.lastname: Gualandi
authors.forename: Luciano
authors.initials: L
authors.lastname: Merlini
authors.forename: Gaetano
authors.initials: G
authors.lastname: Vattemi
authors.forename: Daniela
authors.initials: D
authors.lastname: Perrone
authors.forename: Elena
authors.initials: E
authors.lastname: Marchesi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Sabatelli
authors.forename: Katia
authors.initials: K
authors.lastname: Sparnacci
authors.forename: Michele
authors.initials: M
authors.lastname: Laus
authors.forename: Paolo
authors.initials: P
authors.lastname: Bonaldo
authors.forename: Paola
authors.initials: P
authors.lastname: Rimessi
authors.forename: Paola
authors.initials: P
authors.lastname: Braghetta
authors.forename: Alessandra
authors.initials: A
authors.lastname: Ferlini
mesh_terms: D000818:Animals; D016189:Dystrophin / Q000235:genetics / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D051379:Mice; D018101:Mice, Inbred mdx; D020388:Muscular Dystrophy, Duchenne / Q000188:drug therapy* / Q000378:metabolism*; D053769:Nanocapsules / Q000008:administration & dosage*; D016376:Oligonucleotides, Antisense / Q000008:administration & dosage*; D016896:Treatment Outcome; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D016189:Dystrophin; D053769:Nanocapsules; D016376:Oligonucleotides, Antisense