| First Author | Okutsu M | Year | 2014 |
| Journal | Circ Heart Fail | Volume | 7 |
| Issue | 3 | Pages | 519-30 |
| PubMed ID | 24523418 | Mgi Jnum | J:277983 |
| Mgi Id | MGI:6355707 | Doi | 10.1161/CIRCHEARTFAILURE.113.000841 |
| Citation | Okutsu M, et al. (2014) Extracellular superoxide dismutase ameliorates skeletal muscle abnormalities, cachexia, and exercise intolerance in mice with congestive heart failure. Circ Heart Fail 7(3):519-30 |
| abstractText | BACKGROUND: Congestive heart failure (CHF) is a leading cause of morbidity and mortality, and oxidative stress has been implicated in the pathogenesis of cachexia (muscle wasting) and the hallmark symptom, exercise intolerance. We have previously shown that a nitric oxide-dependent antioxidant defense renders oxidative skeletal muscle resistant to catabolic wasting. Here, we aimed to identify and determine the functional role of nitric oxide-inducible antioxidant enzyme(s) in protection against cardiac cachexia and exercise intolerance in CHF. METHODS AND RESULTS: We demonstrated that systemic administration of endogenous nitric oxide donor S-nitrosoglutathione in mice blocked the reduction of extracellular superoxide dismutase (EcSOD) protein expression, as well as the induction of MAFbx/Atrogin-1 mRNA expression and muscle atrophy induced by glucocorticoid. We further showed that endogenous EcSOD, expressed primarily by type IId/x and IIa myofibers and enriched at endothelial cells, is induced by exercise training. Muscle-specific overexpression of EcSOD by somatic gene transfer or transgenesis (muscle creatine kinase [MCK]-EcSOD) in mice significantly attenuated muscle atrophy. Importantly, when crossbred into a mouse genetic model of CHF (alpha-myosin heavy chain-calsequestrin), MCK-EcSOD transgenic mice had significant attenuation of cachexia with preserved whole body muscle strength and endurance capacity in the absence of reduced HF. Enhanced EcSOD expression significantly ameliorated CHF-induced oxidative stress, MAFbx/Atrogin-1 mRNA expression, loss of mitochondria, and vascular rarefaction in skeletal muscle. CONCLUSIONS: EcSOD plays an important antioxidant defense function in skeletal muscle against cardiac cachexia and exercise intolerance in CHF. |
