Journal Article

Dystrophin restoration in skeletal, heart and skin arrector pili smooth muscle of mdx mice by ZM2 NP–AON complexes

Vattemi, G, Laus, M, Falzarano, S, Ferlini, A, Sabatelli, P, Gualandi, F, Sparnacci, K, Bassi, E, Rimessi, P, Merlini, L, Fabris, M, Maraldi, N M, Perrone, D, Bonaldo, P, Caputo, A, Braghetta, P

2010

Overview

Potentially viable therapeutic approaches for Duchenne muscular dystrophy (DMD) are now within reach. Indeed, clinical trials are currently under way. Two crucial aspects still need to be addressed: maximizing therapeutic efficacy and identifying appropriate and sensible outcome measures. Nevertheless, the end point of these trials remains painful muscle biopsy to show and quantify protein restoration in treated boys. In this study we show that PMMA/N-isopropil-acrylamide+ (NIPAM) nanoparticles (ZM2) bind and convey antisense oligoribonucleotides (AONs) very efficiently. Systemic injection of the ZM2–AON complex restored dystrophin protein synthesis in both skeletal and cardiac muscles of mdx mice, allowing protein localization in up to 40% of muscle fibers. The mdx exon 23 skipping level was up to 20%, as measured by the RealTime assay, and dystrophin restoration was confirmed by both reverse transcription-PCR and western blotting. Furthermore, we verified that dystrophin restoration also occurs in the smooth muscle cells of the dorsal skin arrector pili, an easily accessible histological structure, in ZM2–AON-treated mdx mice, with respect to untreated animals. This finding reveals arrector pili smooth muscle to be an appealing biomarker candidate and a novel low-invasive treatment end point. Furthermore, this marker would also be suitable for subsequent monitoring of the therapeutic effects in DMD patients. In addition, we demonstrate herein the expression of other sarcolemma proteins such as α-, β-, γ- and δ-sarcoglycans in the human skin arrector pili smooth muscle, thereby showing the potential of this muscle as a biomarker for other muscular dystrophies currently or soon to be the object of clinical trials.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: Acrylamide / Acrylamides - administration & dosage / Acrylamides - chemistry / Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy / Animals / Antisense oligonucleotides / Applied cell therapy and gene therapy / Biological and medical sciences / Biomarkers / Biomedical and Life Sciences / Biomedicine / Biopsy / Biotechnology / Cardiac muscle / Care and treatment / Cell Biology / Clinical trials / Duchenne muscular dystrophy / Duchenne's muscular dystrophy / Dystrophin / Dystrophin - biosynthesis / Dystrophin - genetics / Exons / Fundamental and applied biological sciences. Psychology / Gene Expression / Gene Therapy / Genetic aspects / Genetic Therapy - methods / Health aspects / Health. Pharmaceutical industry / Heart / Human Genetics / Humans / Industrial applications and implications. Economical aspects / Localization / Male / Medical sciences / Mice / Mice, Inbred mdx / Muscle, Smooth - metabolism / Muscular Dystrophy, Duchenne - therapy / Nanoparticles / Nanoparticles - administration & dosage / Nanoparticles - chemistry / Nanotechnology / Oligoribonucleotides, Antisense - administration & dosage / Oligoribonucleotides, Antisense - chemistry / Oligoribonucleotides, Antisense - genetics / Physiological aspects / Pili / Polymethyl Methacrylate - administration & dosage / Polymethyl Methacrylate - chemistry / Polymethylmethacrylate / Protein biosynthesis / Proteins / Reverse transcription / Risk factors / Rodents / Sarcoglycans - genetics / Sarcolemma / short-communication / Skeletal muscle / Skeletal system / Skin / Skin - metabolism / Smooth muscle / Transfusions. Complications. Transfusion reactions. Cell and gene therapy / Western blotting