title: Increase in muscle mitochondrial biogenesis does not prevent muscle loss but increased tumor size in a mouse model of acute cancer-induced cachexia.
abstract: Cancer-associated cachexia is a complex metabolic condition characterized by the progressive loss of body fat and deterioration of muscle mass. Although the cellular and molecular mechanisms of cachexia are incompletely understood, previous studies have suggested mitochondrial dysfunction in murine models of cancer cachexia. To better understand the metabolic shift in cancer-induced cachexia, we studied the effects of enhanced oxidative capacity on muscle wasting using transgenic mice over-expressing Peroxisome Proliferator-Activated Receptor gamma Co-activator-1α (PGC-1α) in skeletal muscle in a Lewis lung carcinoma-implanted model. Increased mitochondrial biogenesis was observed in the skeletal muscle of tumor-implanted mice. However, these increases did not prevent or reverse muscle wasting in mice harboring tumors. Moreover, tumor size was increased in muscle PGC-1α over-expressing mice. We found similar levels of circulating inflammatory cytokines in tumor-implanted animals, which was not affected by increased muscle expression of PGC-1α. Our data indicated that increased mitochondrial biogenesis in skeletal muscle is not sufficient to rescue tumor-associated, acute muscle loss, and could promote tumor growth, possibly through the release of myokines.
authors.affiliation: The Sheila and David Fuente Graduate Program in Cancer Biology, University of Miami Miller School of Medicine, Miami, Florida, United States of America.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.forename: Alicia M
authors.initials: AM
authors.lastname: Pickrell
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Zimmers
authors.forename: Carlos T
authors.initials: CT
authors.lastname: Moraes
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002100:Cachexia / Q000209:etiology / Q000473:pathology*; D018827:Carcinoma, Lewis Lung / Q000150:complications* / Q000473:pathology; D016207:Cytokines / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D015850:Interleukin-6 / Q000097:blood; D051379:Mice; D008822:Mice, Transgenic; D008931:Mitochondria, Muscle / Q000502:physiology*; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D009133:Muscular Atrophy / Q000378:metabolism* / Q000473:pathology; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013053:Spectrophotometry; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors
chemical_list: D016207:Cytokines; D017931:DNA Primers; D015850:Interleukin-6; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C485290:Ppargc1a protein, mouse; D015534:Trans-Activators; D014157:Transcription Factors