Phenotypic and metabolic features of mouse diaphragm and gastrocnemius muscles in chronic lung carcinogenesis: influence of underlying emphysema

Abstract

BackgroundMuscle wasting negatively impacts the progress of chronic diseases such as lung cancer (LC) and emphysema, which are in turn interrelated.ObjectivesWe 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.MethodsDiaphragm 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).ResultsCompared 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.ConclusionsIn 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.Electronic supplementary materialThe online version of this article (doi:10.1186/s12967-016-1003-9) contains supplementary material, which is available to authorized users.

Reduced lung cancer burden by selective immunomodulators elicits improvements in muscle proteolysis and strength in cachectic mice

“…In addition, to our knowledge, the mAbs used in this work do not exert any significant direct effects on skeletal muscles (Dai et al, 2013(Dai et al, , 2015Wei et al, 2013). This was a major concern when designing the study as our Fermoselle et al, 2013;Salazar-Degracia et al, 2016) was attenuated in response to immunotherapy of the tumor in this model. Specifically, plasma levels of troponin-I were significantly lower in the cancer-cachexia + mAbs mice than in the nontreated cachectic animals.…”

“…Biological analyses 2.2.1 | Inflammatory cells in tumorsT and B cells and macrophages were identified in tumor sections using specific antibodies against membrane antigens: anti-CD3, anti-CD8, and anti-CD4 (T cells), anti-CD20 (B cells), and anti-CD68 (macrophages) and immunohistochemical procedures(Chacon-Cabrera, Lund-Palau, et al, 2016b;Dai et al, 2013Dai et al, , 2015Salazar-Degracia et al, 2016).…”

“…previously described(Chacon-Cabrera et al, 2014, 2015Chacon- Cabrera, Gea, et al, 2016a;Chacon-Cabrera, Lund-Palau, et al, 2016b;Chacon-Cabrera et al, 2017;Puig-Vilanova et al, 2014;Puig- Vilanova et al, 2015;Salazar-Degracia et al, 2016, 2018.Study markers were identified using the following specific primary antibodies: anti-20S proteasome subunit C8 antibody(1:5,000; BML-PW8110-0100) from Biomol (Plymouth Meeting, PA), anti-protein ubiquitination antibody (1:5000, A-100) from Boston Biochem (Cambridge, MA), anti-muscle ring finger protein-1 antibody (MuRF-1; 1:2000; sc-27642), anti-atrogin-1 antibody (1:1000; sc-166806), anti-tripartite motif-containing protein 32 antibody (TRIM32; 1:500; sc-49265), anti-B-Cell CLL/Lymphoma 2 antibody (BCL-2; 1:1000; sc-7382), anti-BCL2 associated X protein antibody (BAX; 1:1000, sc-526), and anti-glyceraldehyde 3-phosphate dehydrogenase antibody (GAPDH; 1:2000; sc-25778) from Santa Cruz Biotechnology (Santa Cruz, CA). Antigens from all samples were detected using horseradish peroxidase-conjugated secondary antibodies (Jackson ImmunoResearch Inc, West Grove, PA) and a chemiluminescence kit (Thermo Fisher Scientific, Rockford, IL).…”

“…Millipore, Darmstadt, Germany) in both diaphragm and gastrocnemius muscles from all study groups following the manufacturer's instructions and previously published studies(Chacon-Cabrera et al, 2014;Chacon-Cabrera, Lund-Palau, et al, 2016b;Chacon-Cabrera et al, 2017;Salazar-Degracia et al, 2016, 2018.…”

Endoplasmic reticulum stress and unfolded protein response profile in quadriceps of sarcopenic patients with respiratory diseases

“…Despite that no correlations were found between oxidative stress and autophagy or apoptosis markers, these observations suggest that apoptosis may preferentially mediate muscle mass loss in patients with LC-induced cachexia and UPR can be a powerful signaling mechanism. Indeed, previous investigations have also shown that apoptosis rather than proteolysis was the major mechanism leading to muscle wasting in animal models of cancer cachexia (Salazar-Degracia et al, 2016) and to a lower degree in COPD sarcopenia (Agusti et al, 2002).…”