Author(s)

Ana Maria Fleig-Mayer, Alba Ramirez-Sarmiento, Amanda Iglesias, Montserrat Morlá, Carlos Coronell, Diego Rodríguez, Simona Pichinni, Josep Lloreta, Piergiorgio Zuccaro, Xavier Busquets, Joaquim Gea, Jose R. Jardim, Mauricio Orozco-Levi

Centro en Red de Investigación de Enfermedades Respiratorias (CIBERES), Recinto Hospital Joan March Carretera Soller Km. 12, 07110, Bunyola, Mallorca, Illes Balears, Spain.
Centro Universitário do Triangulo (UNITRI), Avenida nicomedes Alves Dos Santos, 4545-Gavea, Uberlandia; Pulmonary Rehabilitation Center, Respiratory Division, Federal University of S?o Paulo, S?o Paulo, Brazil.
Group of Research in Injury, Immune Response and Function (LIF), Municipal Institute of Medical Research (IMIM), Carrer Dr. Aiguader 88, Barcelona, E-08003, Spain.
Laboratorio Di Biochimica Clinica, Istituto Superiore Di Sanitá. Viale Regina Elena 299, 00161, Roma, Ital.
Laboratorio Di Biochimica Clinica, Istituto Superiore Di Sanita. Viale Regina Elena 299, 00161, Roma, Italy.
Respiratory Department, Fundación Cardiovascular de Colombia, Calle 155A 23-58, Floridablanca, Santander, Colombia.
Servei de Pneumologia, Hospital del Mar, Passeig Maritim 25, Barcelona, E-08003, Spain.

Cigarette smoking is the main cause of chronic obstructive pulmonary disease (COPD). Diaphragm injury is observed in patients with COPD. However, the potential role of smoking in triggering or perpetuating muscle injury is unknown. The present study was aimed at evaluating the potential role of commercial tobacco smoke as a direct cause of skeletal muscle injury in experimental conditions. Seventy Wistar rats (170 - 250 g) were assigned to smoking (n = 49) or non-smoking (n = 21) groups. The smoking groups were submitted to a single or multiple (i.e., five or thirty) daily sessions of cigarette smoking in an inhalatory chamber (time length: 2 h each session). The level of exposure was constant and assessed by CO concentrations (50 ppm) and serum cotinine analysis. Animals submitted to a single smoke exposure and the corresponding controls were euthanized in groups at 0 h, 2 h, 4 h, 24 h or 48 h after completing the exposure. Animals submitted to multiple exposures were euthanized at 0 h after smoking. Samples from vastus lateralis muscle were obtained and processed for assessing cell injury and selected protein expression. Monoclonal anti-albumin antibodies were used to identify muscle fibers with sarcolemmal (membrane) injury. Subcellular muscle injury was assessed using transmission electron microscopy (EM). MyoD, myogenin and α-tubulin were immunodetected using western blot techniques. Exposure to cigarette smoke associated with significant membrane damage (mean relative difference (MRD) with controls: +181%, p = 0.004) and sarcomere disruptions (MRD: +226%, p = 0.001). Expression of MyoD and myogenin (normalized to α-tubulin) were significantly increased at 4 h and remained increased at 48 h post-exposure. We conclude that not only a single but also consecutive exposure to tobacco smoke have acute deleterious effects on peripheral muscle structure. A rapid induction of subrogate markers of skeletal muscle stress and repair processes associates to sarcolemmal and sarcomere damage.

Skeletal Muscle, Muscle Injury, Muscle Regeneration, Quadriceps, Cigarette Smoking

Fleig-Mayer, A. , Ramirez-Sarmiento, A. , Iglesias, A. , Morlá, M. , Coronell, C. , Rodríguez, D. , Pichinni, S. , Lloreta, J. , Zuccaro, P. , Busquets, X. , Gea, J. , Jardim, J. and Orozco-Levi, M. (2014) Membrane and Subcellular Muscle Injury Are Induced by Single or Multiple Exposure to Cigarette Smoke. Open Journal of Pathology, 4, 125-137. doi: 10.4236/ojpathology.2014.43019.