title: Phenotypic and metabolic features of mouse diaphragm and gastrocnemius muscles in chronic lung carcinogenesis: influence of underlying emphysema.
abstract: Muscle wasting negatively impacts the progress of chronic diseases such as lung cancer (LC) and emphysema, which are in turn interrelated.
  
  
  
  We hypothesized that muscle atrophy and body weight loss may develop in an experimental mouse model of lung carcinogenesis, that the profile of alterations in muscle fiber phenotype (fiber type composition and morphometry, muscle structural alterations, and nuclear apoptosis), and in muscle metabolism are similar in both respiratory and limb muscles of the tumor-bearing mice, and that the presence of underlying emphysema may influence those events.
  
  
  
  Diaphragm and gastrocnemius muscles of mice with urethane-induced lung cancer (LC-U) with and without elastase-induced emphysema (E-U) and non-exposed controls (N = 8/group) were studied: fiber type composition, morphometry, muscle abnormalities, apoptotic nuclei (immunohistochemistry), and proteolytic and autophagy markers (immunoblotting) at 20- and 35-week exposure times. In the latter cohort, structural contractile proteins, creatine kinase (CK), peroxisome proliferator-activated receptor (PPAR) expression, oxidative stress, and inflammation were also measured. Body and muscle weights were quantified (baseline, during follow-up, and sacrifice).
  
  
  
  Compared to controls, in U and E-U mice, whole body, diaphragm and gastrocnemius weights were reduced. Additionally, both in diaphragm and gastrocnemius, muscle fiber cross-sectional areas were smaller, structural abnormalities, autophagy and apoptotic nuclei were increased, while levels of actin, myosin, CK, PPARs, and antioxidants were decreased, and muscle proteolytic markers did not vary among groups.
  
  
  
  In this model of lung carcinogenesis with and without emphysema, reduced body weight gain and muscle atrophy were observed in respiratory and limb muscles of mice after 20- and 35-week exposure times most likely through increased nuclear apoptosis and autophagy. Underlying emphysema induced a larger reduction in the size of slow- and fast-twitch fibers in the diaphragm of U and E-U mice probably as a result of the greater inspiratory burden imposed onto this muscle.
authors.affiliation: Pulmonology Department-Muscle Wasting and Cachexia in Chronic Respiratory Diseases and Lung Cancer Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB), C/Dr. Aiguader, 88, 08003, Barcelona, Spain.|Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Salazar-Degracia
authors.affiliation: Laboratorio de Biomarcadores, Programa de Tumores Sólidos, Centro de Investigación Médica Aplicada, Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Blanco
authors.affiliation: Pulmonology Department-Muscle Wasting and Cachexia in Chronic Respiratory Diseases and Lung Cancer Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB), C/Dr. Aiguader, 88, 08003, Barcelona, Spain.|Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Barcelona, Spain.
authors.forename: Mònica
authors.initials: M
authors.lastname: Vilà-Ubach
authors.affiliation: Laboratorio de Biomarcadores, Programa de Tumores Sólidos, Centro de Investigación Médica Aplicada, Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Gabriel
authors.initials: G
authors.lastname: de Biurrun
authors.affiliation: Laboratorio de Imagen del Cáncer, Programa de Tumores Sólidos, Centro de Investigación Médica Aplicada, Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Carlos Ortiz
authors.initials: CO
authors.lastname: de Solórzano
authors.affiliation: Laboratorio de Biomarcadores, Programa de Tumores Sólidos, Centro de Investigación Médica Aplicada, Universidad de Navarra, Pamplona, Navarra, Spain.|Departamento de Histología y Anatomía Patológica, Facultades de Medicina y Ciencias, Universidad de Navarra, Pamplona, Spain.|IDISNA, Instituto de Investigaciones Sanitarias de Navarra, Pamplona, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Montuenga
authors.affiliation: Pulmonology Department-Muscle Wasting and Cachexia in Chronic Respiratory Diseases and Lung Cancer Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB), C/Dr. Aiguader, 88, 08003, Barcelona, Spain. ebarreiro@imim.es.|Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Barcelona, Spain. ebarreiro@imim.es.
authors.forename: Esther
authors.initials: E
authors.lastname: Barreiro
mesh_terms: D000818:Animals; D017209:Apoptosis; D001343:Autophagy; D001835:Body Weight; D063646:Carcinogenesis / Q000378:metabolism* / Q000473:pathology*; D016207:Cytokines / Q000378:metabolism; D003964:Diaphragm / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D004646:Emphysema / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D020287:In Situ Nick-End Labeling; D007249:Inflammation / Q000378:metabolism / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D009119:Muscle Contraction; D024510:Muscle Development; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D009124:Muscle Proteins / Q000378:metabolism; D010084:Oxidation-Reduction; D010641:Phenotype; D059748:Proteolysis; D054875:Ubiquitination; D055114:X-Ray Microtomography
chemical_list: D016207:Cytokines; D009124:Muscle Proteins; D008315:Malondialdehyde
keywords: Lung carcinogenesis-induced muscle mass loss; Muscle apoptotic nuclei; Muscle-specific proteins; PPARs proteolytic and autophagy markers; Respiratory and limb muscle atrophy and structural abnormalities; Underlying emphysema