Hindawi Publishing Corporation BioMed Research International Volume 2013, Article ID 527418, 13 pages http://dx.doi.org/10.1155/2013/527418 Research Article Biodistribution and Molecular Studies on Orally Administered Nanoparticle-AON Complexes Encapsulated with Alginate Aiming at Inducing Dystrophin Rescue in mdx Mice Maria Sofia Falzarano, 1 Chiara Passarelli, 2 Elena Bassi, 1 Marina Fabris, 1 Daniela Perrone, 3 Patrizia Sabatelli, 4 Nadir M. Maraldi, 4 Silvia Donà, 5 Rita Selvatici, 1 Paolo Bonaldo, 5 Katia Sparnacci, 6 Michele Laus, 6 Paola Braghetta, 5 Paola Rimessi, 1 and Alessandra Ferlini 1,7 1 Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy 2 Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Diseases, Bambino Ges` u Children’s Hospital, IRCCS, 00146 Rome, Italy 3 Department of Biology and Evolution, University of Ferrara, 44121 Ferrara, Italy 4 IGM-CNR, Unit of Bologna c/o IOR, 40136 Bologna, Italy 5 Department of Biomedical Sciences, University of Padua, 35121 Padua, Italy 6 Department of Environmental and Life Sciences INSTM, University of Eastern Piedmont, 15121 Alessandria, Italy 7 Department of Medical Sciences, Section of Medical Genetics, University of Ferrara, via Fossato di Mortara 74, 44121 Ferrara, Italy Correspondence should be addressed to Alessandra Ferlini; la@unife.it Received 1 July 2013; Revised 10 October 2013; Accepted 14 October 2013 Academic Editor: Akinori Nakamura Copyright © 2013 Maria Soia Falzarano et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We have previously demonstrated that intraperitoneal injections of 2  -O-methyl-phosphorothioate (2  OMePS) antisense oligori- bonucleotides adsorbed onto a cationic core-shell nanoparticles (NPs), termed ZM2, provoke dystrophin restoration in the muscles of mdx mice. he aim of the present work was to evaluate the oral route as an alternative way of administration for ZM2-antisense oligoribonucleotides complexes. he biodistribution and elimination of nanoparticles were evaluated ater single and multiple oral doses of IR-dye conjugated nanoparticles. Labeled nanoparticles were tracked in vivo as well as in tissue cryosections, urines and feces by Odyssey infrared imaging system, and revealed a permanence in the intestine and abdominal lymph nodes for 72 hours to 7 days before being eliminated. We subsequently tested alginate-free and alginate-encapsulated ZM2-antisense oligoribonucleotides (AON) complexes orally administered 2 and 3 times per week, respectively, in mdx mice for a total of 12 weeks. Treatment with alginate ZM2-AON induced a slight dystrophin rescue in diaphragm and intestine smooth muscles, while no dystrophin was detected in alginate-free ZM2-AON treated mice. hese data encourage further experiments on oral administration testing of NP and AON complexes, possibly translatable in oligoribonucleotides-mediated molecular therapies. 1. Introduction he X-linked recessive Duchenne muscular dystrophy (DMD) afects 1 in 3500 newborn boys [1], and it is caused by the loss of dystrophin expression. he antisense mediated exon skipping approach represents a promising therapy for DMD. It is based on the possibility to convert a severe phenotype (DMD) into a milder form (Becker muscular dystrophy) acting on dystrophin pre-mRNA [2, 3]. Two AON chemistries, 2  OMePS and phosphorodiami- date morpholino oligomer (PMO), have already been the subject of clinical trials in humans [1, 4–8]. Phosphorothioate