title: Peptide conjugation of 2'-O-methyl phosphorothioate antisense oligonucleotides enhances cardiac uptake and exon skipping in mdx mice.
abstract: Antisense oligonucleotide (AON)-mediated exon skipping is a promising therapeutic approach for Duchenne muscular dystrophy that is currently being tested in various clinical trials. This approach is based on restoring the open reading frame of dystrophin transcripts resulting in shorter but partially functional dystrophin proteins as found in patients with Becker muscular dystrophy. After systemic administration, a large proportion of AONs ends up in the liver and kidneys. Therefore, enhancing AON uptake by skeletal and cardiac muscle would improve the AONs' therapeutic effect. For phosphorodiamidate morpholino oligomer, AONs use nonspecific positively charged cell penetrating peptides to enhance efficacy. However, this is challenging for negatively charged 2'-O-methyl phosphorothioate oligomer. Therefore, we screened a 7-mer phage display peptide library to identify muscle and heart homing peptides in vivo in the mdx mouse model and found a promising candidate peptide capable of binding muscle cells in vitro and in vivo. Upon systemic administration in dystrophic mdx mice, conjugation of a 2'-O-methyl phosphorothioate AON to this peptide indeed improved uptake in skeletal and cardiac muscle, and resulted in higher exon skipping levels with a significant difference in heart and diaphragm. Based on these results, peptide conjugation represents an interesting strategy to enhance the therapeutic effect of exon skipping with 2'-O-methyl phosphorothioate AONs for Duchenne muscular dystrophy.
authors: 1 Department of Human Genetics, Leiden University Medical Center , Leiden, The Netherlands .
authors: Silvana M G
authors: SM
authors: Jirka
authors: Hans
authors: H
authors: Heemskerk
authors: Christa L
authors: CL
authors: Tanganyika-de Winter
authors: Daan
authors: D
authors: Muilwijk
authors: Kar Him
authors: KH
authors: Pang
authors: Peter C
authors: PC
authors: de Visser
authors: Anneke
authors: A
authors: Janson
authors: Tatyana G
authors: TG
authors: Karnaoukh
authors: Rick
authors: R
authors: Vermue
authors: Peter A C
authors: PA
authors: 't Hoen
authors: Judith C T
authors: JC
authors: van Deutekom
authors: Begoña
authors: B
authors: Aguilera
authors: Annemieke
authors: A
authors: Aartsma-Rus
mesh_terms: D000818:Animals; D016189:Dystrophin / Q000235:genetics; D005091:Exons; D006801:Humans; D008297:Male; D051379:Mice; D018101:Mice, Inbred mdx; D018482:Muscle, Skeletal / Q000378:metabolism; D009137:Muscular Dystrophy, Animal / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D009154:Mutation; D009206:Myocardium / Q000378:metabolism; D016376:Oligonucleotides, Antisense / Q000737:chemistry* / Q000235:genetics / Q000627:therapeutic use*; D019151:Peptide Library; D020135:Peptide Nucleic Acids / Q000737:chemistry / Q000235:genetics / Q000627:therapeutic use; D054735:Phosphorothioate Oligonucleotides / Q000737:chemistry* / Q000235:genetics / Q000627:therapeutic use*; D052416:Targeted Gene Repair / Q000379:methods
chemical_list: D016189:Dystrophin; D016376:Oligonucleotides, Antisense; D019151:Peptide Library; D020135:Peptide Nucleic Acids; D054735:Phosphorothioate Oligonucleotides; C085339:apo-dystrophin 1