Partial restoration of cardiac function with ΔPDZ nNOS in aged mdx model of Duchenne cardiomyopathy.
Transgenic gene deletion/over-expression studies have established the cardioprotective role of neuronal nitric oxide synthase (nNOS). However, it remains unclear whether nNOS-mediated heart protection can be translated to gene therapy. In this study, we generated an adeno-associated virus (AAV) nNOS vector and tested its therapeutic efficacy in the aged mdx model of Duchenne cardiomyopathy. A PDZ domain-deleted nNOS gene (ΔPDZ nNOS) was packaged into tyrosine mutant AAV-9 and delivered to the heart of ~14-month-old female mdx mice, a phenotypic model of Duchenne cardiomyopathy. Seven months later, we observed robust nNOS expression in the myocardium. Supra-physiological ΔPDZ nNOS expression significantly reduced myocardial fibrosis, inflammation and apoptosis. Importantly, electrocardiography and left ventricular hemodynamics were significantly improved in treated mice. Additional studies revealed increased phosphorylation of phospholamban and p70S6K. Collectively, we have demonstrated the therapeutic efficacy of the AAV ΔPDZ nNOS vector in a symptomatic Duchenne cardiomyopathy model. Our results suggest that the cardioprotective role of ΔPDZ nNOS is likely through reduced apoptosis, enhanced phospholamban phosphorylation and improved Akt/mTOR/p70S6K signaling. Our study has opened the door to treat Duchenne cardiomyopathy with ΔPDZ nNOS gene transfer.
Department of Molecular Microbiology and Immunology, University of Missouri-Columbia, Columbia, MO 65212, USA laiy@missouri.edu duand@missouri.edu.
Yi
Y
Lai
Department of Molecular Microbiology and Immunology, University of Missouri-Columbia, Columbia, MO 65212, USA.
Junling
J
Zhao
Department of Molecular Microbiology and Immunology, University of Missouri-Columbia, Columbia, MO 65212, USA.
Yongping
Y
Yue
Department of Molecular Microbiology and Immunology, University of Missouri-Columbia, Columbia, MO 65212, USA.
Nalinda B
NB
Wasala
Department of Molecular Microbiology and Immunology, University of Missouri-Columbia, Columbia, MO 65212, USA laiy@missouri.edu duand@missouri.edu.
Dongsheng
D
Duan
D000818:Animals; D017209:Apoptosis; D002135:Calcium-Binding Proteins / Q000378:metabolism; D009202:Cardiomyopathies / Q000150:complications / Q000503:physiopathology* / Q000628:therapy*; D000229:Dependovirus / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism / Q000627:therapeutic use; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D018101:Mice, Inbred mdx; D009137:Muscular Dystrophy, Animal / Q000503:physiopathology* / Q000628:therapy*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D052248:Nitric Oxide Synthase Type I / Q000235:genetics* / Q000378:metabolism; D010766:Phosphorylation; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D015398:Signal Transduction; D000099211:Phospholamban
D002135:Calcium-Binding Proteins; D052248:Nitric Oxide Synthase Type I; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D000099211:Phospholamban; C496321:Nos1 protein, mouse