Article first published online: 20 July 2018
Electromyostimulation to fight atrophy and to build muscle: facts and numbers
In recent years, electrical myostimulation (EMS) is becoming more and more popular to increase muscle function and muscle weight. Especially it is applied in healthy individual after injury to rebuild muscle mass and in severely atrophic patients who are not able or willing to perform conventional exercise training programs. Studies in experimental models as well as in human subjects confirmed that EMS can increase muscle mass by around 1% and improve muscle function by around 10–15% after 5–6 weeks of treatment. Despite a severe increase in circulating creatine kinase during the first session, EMS can be regarded as a safe therapeutic intervention. At the molecular level, EMS improves the anabolic/catabolic balance and stimulates the regenerative capacity of satellite cells. EMS intensity should be as high as individually tolerated, and a minimum of three sessions per week [large pulses (between 300–450 μs), high frequency (50–100 Hz in young and around 30 Hz in older individuals)] for at least 5–6 weeks should be performed. EMS improved functional performances more effectively than voluntary training and counteracted fast type muscle fibre atrophy, typically associated with sarcopenia. The effect of superimposing EMS on conventional exercise training to achieve more muscle mass and better function is still discussed controversially. Nevertheless, EMS should not be regarded as a replacement of exercise training per se, since the beneficial effect of exercise training is not just relying on building muscle mass but it also exerts positive effects on endothelial, myocardial, and cognitive function.
Adams, V. (2018) Electromyostimulation to fight atrophy and to build muscle: facts and numbers. Journal of Cachexia, Sarcopenia and Muscle, https://doi.org/10.1002/jcsm.12332.
Article first published online: 13 APR 2018
Li-Ning Peng, Wei-Ju Lee, Li-Kuo Liu, Ming-Hsien Lin, Liang-Kung Chen
Healthy community-living older men differ from women in associations between myostatin levels and skeletal muscle massBackground
Myostatin is a negative regulator of muscle growth but the relationship between serum myostatin levels and muscle mass is unclear. This study investigated the association between serum myostatin levels and skeletal muscle mass among healthy older community residents in Taiwan, to evaluate the potential of serum myostatin as a biomarker for diagnosing sarcopenia and/or evaluating the effect of its treatment.
Study data were excerpted from a random subsample of the I-Lan Longitudinal Aging Study population. Serum myostatin levels were determined and categorized into tertiles (low, medium, high). Relative appendicular skeletal muscle mass (RASM) was calculated as appendicular lean body mass by dual-energy X-ray absorptiometry divided by height squared (kg/m2). Low muscle mass was defined as recommended by the Asian Working Group for Sarcopenia.
The analytic study sample comprised 463 adults (mean age: 69.1 years; 49.5% men). Compared with subjects with normal RASM, those with lower RASM were older and frailer, with significantly higher prevalence of malnutrition, lower serum dehydroepiandrosterone (DHEA) levels, and were more likely to have low serum myostatin status. Multivariable logistic regression analysis showed that male sex (OR 3.60, 95% CI 1.30–9.92), malnutrition (OR 4.39, 95% CI 1.56–12.36), DHEA (OR 0.99, 95% CI 0.99–1.00), and low myostatin (OR 3.23, 95% CI 1.49–7.01) were all independent risk factors for low RASM (all P < 0.05). In men, DHEA (OR 0.99, 95% CI 0.98–1.00) and low myostatin (OR 4.89, 95% CI 1.79–13.37) were significantly associated with low RASM (both P < 0.05); however, only malnutrition was associated with low RASM in women (OR 13.59, 95% CI 2.22–83.25, P < 0.05).
Among healthy community-living older adults, low serum myostatin levels were associated with low skeletal muscle mass in men, but not in women. Our results do not support using serum myostatin levels to diagnose sarcopenia, or to monitor how it responds to treatments. Further research is needed to understand why men apparently differ from women in the interrelationship between their myostatin levels and muscle mass.
Peng, L.-N., Lee, W.-J., Liu, L.-K., Lin, M.-H., and Chen, L.-K. (2018) Healthy community-living older men differ from women in associations between myostatin levels and skeletal muscle mass. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12302.
Article first published online: 22 MAY 2018
Riyo Komatsu, Tatsuma Okazaki, Satoru Ebihara, Makoto Kobayashi, Yoko Tsukita, Mayumi Nihei, Hisatoshi Sugiura, Kaijun Niu, Takae Ebihara, Masakazu Ichinose
Aspiration pneumonia induces muscle atrophy in the respiratory, skeletal, and swallowing systems
Repetition of the onset of aspiration pneumonia in aged patients is common and causes chronic inflammation. The inflammation induces proinflammatory cytokine production and atrophy in the muscles. The proinflammatory cytokines induce muscle proteolysis by activating calpains and caspase‐3, followed by further degradation by the ubiquitin‐proteasome system. Autophagy is another pathway of muscle atrophy. However, little is known about the relationship between aspiration pneumonia and muscle. For swallowing muscles, it is not clear whether they produce cytokines. The main objective of this study was to determine whether aspiration pneumonia induces muscle atrophy in the respiratory (the diaphragm), skeletal (the tibialis anterior, TA), and swallowing (the tongue) systems, and their possible mechanisms.
We employed a mouse aspiration pneumonia model and computed tomography (CT) scans of aged pneumonia patients. To induce aspiration pneumonia, mice were inoculated with low dose pepsin and lipopolysaccharide solution intra‐nasally 5 days a week. The diaphragm, TA, and tongue were isolated, and total RNA, proteins, and frozen sections were stored. Quantitative real‐time polymerase chain reaction determined the expression levels of proinflammatory cytokines, muscle E3 ubiquitin ligases, and autophagy related genes. Western blot analysis determined the activation of the muscle proteolysis pathway. Frozen sections determined the presence of muscle atrophy. CT scans were used to evaluate the muscle atrophy in aged aspiration pneumonia patients.
The aspiration challenge enhanced the expression levels of proinflammatory cytokines in the diaphragm, TA, and tongue. Among muscle proteolysis pathways, the aspiration challenge activated caspase‐3 in all the three muscles examined, whereas calpains were activated in the diaphragm and the TA but not in the tongue. Activation of the ubiquitin‐proteasome system was detected in all the three muscles examined. The aspiration challenge activated autophagy in the TA and the tongue, whereas weak or little activation was detected in the diaphragm. The aspiration challenge resulted in a greater proportion of smaller myofibers than in controls in the diaphragm, TA, and tongue, suggesting muscle atrophy. CT scans clearly showed that aspiration pneumonia was followed by muscle atrophy in aged patients.
Aspiration pneumonia induced muscle atrophy in the respiratory, skeletal, and swallowing systems in a preclinical animal model and in human patients. Diaphragmatic atrophy may weaken the force of cough to expectorate sputum or mis‐swallowed contents. Skeletal muscle atrophy may cause secondary sarcopenia. The atrophy of swallowing muscles may weaken the swallowing function. Thus, muscle atrophy could become a new therapeutic target of aspiration pneumonia.
Komatsu, R., Okazaki, T., Ebihara, S., Kobayashi, M., Tsukita, Y., Nihei, M., Sugiura, H., Niu, K., Ebihara, T., and Ichinose, M. (2018) Aspiration pneumonia induces muscle atrophy in the respiratory, skeletal, and swallowing systems. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12297.
Article first published online: 16 APR 2018
Jingjie Xiao, Bette J. Caan, Erin Weltzien, Elizabeth M. Cespedes Feliciano, Candyce H. Kroenke, Jeffrey A. Meyerhardt, Vickie E. Baracos, Marilyn L. Kwan, Adrienne L. Castillo, Carla M. Prado
Associations of pre-existing co-morbidities with skeletal muscle mass and radiodensity in patients with non-metastatic colorectal cancerBackground and aim
Co-morbidities and computerized tomography-measured muscle abnormalities are both common in cancer patients and independently adversely influence clinical outcomes. Muscle abnormalities are also evident in other diseases, such as diabetes and obesity. This study examined for the first time the association between co-morbidities and muscle abnormalities in patients diagnosed with colorectal cancer (CRC).
This cross-sectional study included 3051 non-metastatic patients with Stages I–III CRC. Muscle abnormalities, measured at diagnosis, were defined as low skeletal muscle mass index (SMI) or low skeletal muscle radiodensity (SMD) quantified using computerized tomography images using optimal stratification. Co-morbidities included in the Charlson index were ascertained. ?2 tests were used to compare the prevalence of co-morbidities by the presence or absence of each muscle abnormality. Logistic regressions were performed to evaluate which co-morbidities predicted muscle abnormalities adjusting for age, sex, body mass index, weight change, cancer stage, cancer site, race/ethnicity, and smoking.
Mean age was 63 years; 50% of patients were male. The prevalence of low SMI and low SMD were 43.1% and 30.2%, respectively. Co-morbidities examined were more prevalent in patients with low SMD than in those with normal SMD, and most remained independent predictors of low SMD after adjustment for covariates. Co-morbidities associated with higher odds of low SMD included myocardial infarction [odds ratio (OR) = 1.77, P = 0.023], congestive heart failure (OR = 3.27, P < 0.001), peripheral vascular disease (OR = 2.15, P = 0.002), diabetes with or without complications (OR = 1.61, P = 0.008; OR = 1.46, P = 0.003, respectively), and renal disease (OR = 2.21, P < 0.001). By contrast, only diabetes with complications was associated with lower odds of low SMI (OR = 0.64, P = 0.007).
Prevalence of muscle abnormalities was high in patients with non-metastatic CRC. Pre-existing co-morbidities were associated with low SMD, suggestive of a potential shared mechanism between fat infiltration into muscle and each of these co-morbidities.
Xiao, J., Caan, B. J., Weltzien, E., Cespedes Feliciano, E. M., Kroenke, C. H., Meyerhardt, J. A., Baracos, V. E., Kwan, M. L., Castillo, A. L., and Prado, C. M. (2018) Associations of pre-existing co-morbidities with skeletal muscle mass and radiodensity in patients with non-metastatic colorectal cancer. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12301.
Article first published online: 15 May 2018
Justin C. Brown, Bette J. Caan, Jeffrey A. Meyerhardt, Erin Weltzien, Jingjie Xiao, Elizabeth M. Cespedes Feliciano, Candyce H. Kroenke, Adrienne Castillo, Marilyn L. Kwan, Carla M. Prado
The deterioration of muscle mass and radiodensity is prognostic of poor survival in stage I–III colorectal cancer: a population‐based cohort study (C‐SCANS)
Muscle abnormalities such as low muscle mass and low muscle radiodensity are well known risk factors for unfavourable cancer prognosis. However, little is known in regard to the degree and impact of longitudinal changes in muscle mass and radiodensity within the context of cancer. Here, we explore the relationship between muscle wasting and mortality in a large population‐based study of patients with non‐metastatic colorectal cancer (CRC).
A total of 1924 patients with stage I–III CRC who underwent surgical resection in the Kaiser Permanente Northern California Health System were included. Muscle mass and radiodensity were quantified using computed tomography images obtained at diagnosis and after approximately 14 months. Cox proportional‐hazards models were used to estimate hazard ratios for all‐cause mortality.
The hazard ratio for all‐cause mortality among patients with the largest deterioration in muscle mass (≥2 SD; ≥11.4% loss from baseline), as compared with those who remained stable (±1 SD; 0.0 ± 5.7%) was 2.15 [95% confidence interval (CI): 1.59–2.92; P < 0.001]. The hazard ratio for all‐cause mortality among patients who experienced the largest deterioration in muscle radiodensity (≥2 SD; ≥20.2% loss from baseline), as compared with those who remained stable (±1 SD; 0.0 ± 10.1%) was 1.61 (95% CI: 1.20–2.15; P = 0.002).
In patients with stage I–III CRC, muscle wasting is a risk factor for mortality, independent of change in body mass and other body composition parameters.
Brown, J. C., Caan, B. J., Meyerhardt, J. A., Weltzien, E., Xiao, J., Cespedes Feliciano, E. M., Kroenke, C. H., Castillo, A., Kwan, M. L., and Prado, C. M. (2018) The deterioration of muscle mass and radiodensity is prognostic of poor survival in stage I–III colorectal cancer: a population-based cohort study (C-SCANS). Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12305.
Article first published online: 05 July 2018
Joshua K. Kays, Safi Shahda, Melissa Stanley, Teresa M. Bell, Bert H. O'Neill, Marc D. Kohli, Marion E. Couch, Leonidas G. Koniaris, Teresa A. Zimmers
Three cachexia phenotypes and the impact of fat‐only loss on survival in FOLFIRINOX therapy for pancreatic cancer
By the traditional definition of unintended weight loss, cachexia develops in ~80% of patients with pancreatic ductal adenocarcinoma (PDAC). Here, we measure the longitudinal body composition changes in patients with advanced PDAC undergoing 5‐fluorouracil, leucovorin, irinotecan, and oxaliplatin therapy.
We performed a retrospective review of 53 patients with advanced PDAC on 5‐fluorouracil, leucovorin, irinotecan, and oxaliplatin as first line therapy at Indiana University Hospital from July 2010 to August 2015. Demographic, clinical, and survival data were collected. Body composition measurement by computed tomography (CT), trend, univariate, and multivariate analysis were performed.
Among all patients, three cachexia phenotypes were identified. The majority of patients, 64%, had Muscle and Fat Wasting (MFW), while 17% had Fat‐Only Wasting (FW) and 19% had No Wasting (NW). NW had significantly improved overall median survival (OMS) of 22.6 months vs. 13.0 months for FW and 12.2 months for MFW (P = 0.02). FW (HR = 5.2; 95% confidence interval = 1.5–17.3) and MFW (HR = 1.8; 95% confidence interval = 1.1–2.9) were associated with an increased risk of mortality compared with NW. OMS and risk of mortality did not differ between FW and MFW. Progression of disease, sarcopenic obesity at diagnosis, and primary tail tumours were also associated with decreased OMS. On multivariate analysis, cachexia phenotype and chemotherapy response were independently associated with survival. Notably, CT‐based body composition analysis detected tissue loss of >5% in 81% of patients, while the traditional definition of >5% body weight loss identified 56.6%.
Distinct cachexia phenotypes were observed in this homogeneous population of patients with equivalent stage, diagnosis, and first‐line treatment. This suggests cellular, molecular, or genetic heterogeneity of host or tumour. Survival among patients with FW was as poor as for MFW, indicating adipose tissue plays a crucial role in cachexia and PDAC mortality. Adipose tissue should be studied for its mechanistic contributions to cachexia.
Kays, J. K., Shahda, S., Stanley, M., Bell, T. M., O'Neill, B. H., Kohli, M. D., Couch, M. E., Koniaris, L. G., and Zimmers, T. A. (2018) Three cachexia phenotypes and the impact of fat‐only loss on survival in FOLFIRINOX therapy for pancreatic cancer. Journal of Cachexia, Sarcopenia and Muscle, https://doi.org/10.1002/jcsm.12307.
Article first published online: 15 July 2018
Fabrizio Pin Rafael Barreto Yukiko Kitase Sumegha Mitra Carlie E. Erne Leah J. Novinger Teresa A. Zimmers Marion E. Couch Lynda F. Bonewald Andrea Bonetto
Growth of ovarian cancer xenografts causes loss of muscle and bone mass: a new model for the study of cancer cachexia
Cachexia frequently occurs in women with advanced ovarian cancer (OC), along with enhanced inflammation. Despite being responsible for one third of all cancer deaths, cachexia is generally under‐studied in OC due to a limited number of pre‐clinical animal models. We aimed to address this gap by characterizing the cachectic phenotype in a mouse model of OC.
Nod SCID gamma mice (n = 6–10) were injected intraperitoneally with 1 × 107 ES‐2 human OC cells to mimic disseminated abdominal disease. Muscle size and strength, as well as bone morphometry, were assessed. Tumour‐derived effects on muscle fibres were investigated in C2C12 myotube cultures. IL‐6 levels were detected in serum and ascites from tumour hosts, as well as in tumour sections.
In about 2 weeks, ES‐2 cells developed abdominal tumours infiltrating omentum, mesentery, and adjacent organs. The ES‐2 tumours caused severe cachexia with marked loss of body weight (–12%, P < 0.01) and ascites accumulation in the peritoneal cavity (4.7 ± 1.5 mL). Skeletal muscles appeared markedly smaller in the tumour‐bearing mice (approximately –35%, P < 0.001). Muscle loss was accompanied by fibre atrophy, consistent with reduced muscle cross‐sectional area (–34%, P < 0.01) and muscle weakness (–50%, P < 0.001). Body composition assessment by dual‐energy X‐ray absorptiometry revealed decreased bone mineral density (–8%, P < 0.01) and bone mineral content (–19%, P < 0.01), also consistent with reduced trabecular bone in both femurs and vertebrae, as suggested by micro‐CT imaging of bone morphometry. In the ES‐2 mouse model, cachexia was also associated with high tumour‐derived IL‐6 levels in plasma and ascites (26.3 and 279.6 pg/mL, respectively) and with elevated phospho‐STAT3 (+274%, P < 0.001), reduced phospho‐AKT (–44%, P < 0.001) and decreased mitochondrial proteins, as well as with increased protein ubiquitination (+42%, P < 0.001) and expression of ubiquitin ligases in the skeletal muscle of tumour hosts. Similarly, ES‐2 conditioned medium directly induced fibre atrophy in C2C12 mouse myotubes (–16%, P < 0.001), consistent with elevated phospho‐STAT3 (+1.4‐fold, P < 0.001) and altered mitochondrial homoeostasis and metabolism, while inhibition of the IL‐6/STAT3 signalling by means of INCB018424 was sufficient to restore the myotubes size.
Our results suggest that the development of ES‐2 OC promotes muscle atrophy in both in vivo and in vitro conditions, accompanied by loss of bone mass, enhanced muscle protein catabolism, abnormal mitochondrial homoeostasis, and elevated IL‐6 levels. Therefore, this represents an appropriate model for the study of OC cachexia. Our model will aid in identifying molecular mediators that could be effectively targeted in order to improve muscle wasting associated with OC.
Pin, F., Barreto, R., Kitase, Y., Mitra, S., Erne, C. E., Novinger, L. J., Zimmers, T. A., Couch, M. E., Bonewald, L. F., and Bonetto, A. (2018) Growth of ovarian cancer xenografts causes loss of muscle and bone mass: a new model for the study of cancer cachexia. Journal of Cachexia, Sarcopenia and Muscle, https://doi.org/10.1002/jcsm.12311.
Article first published online: 26 MAR 2018
Joseph Bohlen, Sarah L. McLaughlin, Hannah Hazard-Jenkin, Aniello M. Infante, Cortney Montgomery, Mary Davis, Emidio E. Pistilli
Dysregulation of metabolic-associated pathways in muscle of breast cancer patients: preclinical evaluation of interleukin-15 targeting fatigueBackground
Breast cancer patients report a perception of increased muscle fatigue, which can persist following surgery and standardized therapies. In a clinical experiment, we tested the hypothesis that pathways regulating skeletal muscle fatigue are down-regulated in skeletal muscle of breast cancer patients and that different muscle gene expression patterns exist between breast tumour subtypes. In a preclinical study, we tested the hypothesis that mammary tumour growth in mice induces skeletal muscle fatigue and that overexpression of the cytokine interleukin-15 (IL-15) can attenuate mammary tumour-induced muscle fatigue.
Early stage non-metastatic female breast cancer patients (n = 14) and female non-cancer patients (n = 6) provided a muscle biopsy of the pectoralis major muscle during mastectomy, lumpectomy, or breast reconstruction surgeries. The breast cancer patients were diagnosed with either luminal (ER+/PR+, n = 6), triple positive (ER+/PR+/Her2/neu+, n = 5), or triple negative (ER-/PR-/Her2/neu-, n = 3) breast tumours and were being treated with curative intent either with neoadjuvant chemotherapy followed by surgery or surgery followed by standard post-operative therapy. Biopsies were used for RNA-sequencing to compare the skeletal muscle gene expression patterns between breast cancer patients and non-cancer patients. The C57BL/6 mouse syngeneic mammary tumour cell line, E0771, was used to induce mammary tumours in immunocompetent mice, and isometric muscle contractile properties and fatigue properties were analysed following 4 weeks of tumour growth.
RNA-sequencing and subsequent bioinformatics analyses revealed a dysregulation of canonical pathways involved in oxidative phosphorylation, mitochondrial dysfunction, peroxisome proliferator-activated receptor signalling and activation, and IL-15 signalling and production. In a preclinical mouse model of breast cancer, the rate of muscle fatigue was greater in mice exposed to mammary tumour growth for 4 weeks, and this greater muscle fatigue was attenuated in transgenic mice that overexpressed the cytokine IL-15.
Our data identify novel genes and pathways dysregulated in the muscles of breast cancer patients with early stage non-metastatic disease, with particularly aberrant expression among genes that would predispose these patients to greater muscle fatigue. Furthermore, we demonstrate that IL-15 overexpression can attenuate muscle fatigue associated with mammary tumour growth in a preclinical mouse model of breast cancer. Therefore, we propose that skeletal muscle fatigue is an inherent consequence of breast tumour growth, and this greater fatigue can be targeted therapeutically.
Bohlen, J., McLaughlin, S. L., Hazard-Jenkins, H., Infante, A. M., Montgomery, C., Davis, M., and Pistilli, E. E. (2018) Dysregulation of metabolic-associated pathways in muscle of breast cancer patients: preclinical evaluation of interleukin-15 targeting fatigue. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12294.
Article first published online: 16 APR 2018
Pietro Spitali, Kristina Hettne, Roula Tsonaka, Mohammed Charrout, Janneke van den Bergen, Zaïda Koeks, Hermien E. Kan, Melissa T. Hooijmans, Andreas Roos, Volker Straub, Francesco Muntoni,Cristina Al-Khalili-Szigyarto Marleen J.A. Koel-Simmelink Charlotte E. Teunissen Hanns Lochmüller, Erik H. Niks, Annemieke Aartsma-Rus
Tracking disease progression non-invasively in Duchenne and Becker muscular dystrophiesBackground
Analysis of muscle biopsies allowed to characterize the pathophysiological changes of Duchenne and Becker muscular dystrophies (D/BMD) leading to the clinical phenotype. Muscle tissue is often investigated during interventional dose finding studies to show in situ proof of concept and pharmacodynamics effect of the tested drug. Less invasive readouts are needed to objectively monitor patients' health status, muscle quality, and response to treatment. The identification of serum biomarkers correlating with clinical function and able to anticipate functional scales is particularly needed for personalized patient management and to support drug development programs.
A large-scale proteomic approach was used to identify serum biomarkers describing pathophysiological changes (e.g. loss of muscle mass), association with clinical function, prediction of disease milestones, association with in vivo 31P magnetic resonance spectroscopy data and dystrophin levels in muscles. Cross-sectional comparisons were performed to compare DMD patients, BMD patients, and healthy controls. A group of DMD patients was followed up for a median of 4.4 years to allow monitoring of individual disease trajectories based on yearly visits.
Cross-sectional comparison enabled to identify 10 proteins discriminating between healthy controls, DMD and BMD patients. Several proteins (285) were able to separate DMD from healthy, while 121 proteins differentiated between BMD and DMD; only 13 proteins separated BMD and healthy individuals. The concentration of specific proteins in serum was significantly associated with patients' performance (e.g. BMP6 serum levels and elbow flexion) or dystrophin levels (e.g. TIMP2) in BMD patients. Analysis of longitudinal trajectories allowed to identify 427 proteins affected over time indicating loss of muscle mass, replacement of muscle by adipose tissue, and cardiac involvement. Over-representation analysis of longitudinal data allowed to highlight proteins that could be used as pharmacodynamic biomarkers for drugs currently in clinical development.
Serum proteomic analysis allowed to not only discriminate among DMD, BMD, and healthy subjects, but it enabled to detect significant associations with clinical function, dystrophin levels, and disease progression.
Spitali, P., Hettne, K., Tsonaka, R., Charrout, M., van den Bergen, J., Koeks, Z., Kan, H. E., Hooijmans, M. T., Roos, A., Straub, V., Muntoni, F., Al-Khalili-Szigyarto, C., Koel-Simmelink, M. J. A., Teunissen, C. E., Lochmüller, H., Niks, E. H., and Aartsma-Rus, A. (2018) Tracking disease progression non-invasively in Duchenne and Becker muscular dystrophies. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12304.
Article first published online: 21 MAY 2018
Andrea Cerquone Perpetuini, Andrea David Re Cecconi, Michela Chiappa, Giulia Benedetta Martinelli, Claudia Fuoco, Giovanni Desiderio, Luisa Castagnoli, Cesare Gargioli, Rosanna Piccirillo, Gianni Cesareni
Group I Paks support muscle regeneration and counteract cancer‐associated muscle atrophy
Skeletal muscle is characterized by an efficient regeneration potential that is often impaired during myopathies. Understanding the molecular players involved in muscle homeostasis and regeneration could help to find new therapies against muscle degenerative disorders. Previous studies revealed that the Ser/Thr kinase p21 protein‐activated kinase 1 (Pak1) was specifically down‐regulated in the atrophying gastrocnemius of Yoshida hepatoma‐bearing rats. In this study, we evaluated the role of group I Paks during cancer‐related atrophy and muscle regeneration.
We examined Pak1 expression levels in the mouse Tibialis Anterior muscles during cancer cachexia induced by grafting colon adenocarcinoma C26 cells and in vitro by dexamethasone treatment. We investigated whether the overexpression of Pak1 counteracts muscle wasting in C26‐bearing mice and in vitro also during interleukin‐6 (IL6)‐induced or dexamethasone‐induced C2C12 atrophy. Moreover, we analysed the involvement of group I Paks on myogenic differentiation in vivo and in vitro using the group I chemical inhibitor IPA‐3.
We found that Pak1 expression levels are reduced during cancer‐induced cachexia in the Tibialis Anterior muscles of colon adenocarcinoma C26‐bearing mice and in vitro during dexamethasone‐induced myotube atrophy. Electroporation of muscles of C26‐bearing mice with plasmids directing the synthesis of PAK1 preserves fiber size in cachectic muscles by restraining the expression of atrogin‐1 and MuRF1 and possibly by inducing myogenin expression. Consistently, the overexpression of PAK1 reduces the dexamethasone‐induced expression of MuRF1 in myotubes and increases the phospho‐FOXO3/FOXO3 ratio. Interestingly, the ectopic expression of PAK1 counteracts atrophy in vitro by restraining the IL6‐Stat3 signalling pathway measured in luciferase‐based assays and by reducing rates of protein degradation in atrophying myotubes exposed to IL6. On the other hand, we observed that the inhibition of group I Paks has no effect on myotube atrophy in vitro and is associated with impaired muscle regeneration in vivo and in vitro. In fact, we found that mice treated with the group I inhibitor IPA‐3 display a delayed recovery from cardiotoxin‐induced muscle injury. This is consistent with in vitro experiments showing that IPA‐3 impairs myogenin expression and myotube formation in vessel‐associated myogenic progenitors, C2C12 myoblasts, and satellite cells. Finally, we observed that IPA‐3 reduces p38α/β phosphorylation that is required to proceed through various stages of satellite cells differentiation: activation, asymmetric division, and ultimately myotube formation.
Our data provide novel evidence that is consistent with group I Paks playing a central role in the regulation of muscle homeostasis, atrophy and myogenesis.
Cerquone Perpetuini, A., Re Cecconi, A. D., Chiappa, M., Martinelli, G. B., Fuoco, C., Desiderio, G., Castagnoli, L., Gargioli, C., Piccirillo, R., and Cesareni, G. (2018) Group I Paks support muscle regeneration and counteract cancer‐associated muscle atrophy. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12303.
Article first published online: 14 MAY 2018
Daniel R. Moore, Ryan P. Kelly, Michaela C. Devries, Tyler A. Churchward‐Venne, Stuart M. Phillips, Gianni Parise, Adam P. Johnston
Low‐load resistance exercise during inactivity is associated with greater fibre area and satellite cell expression in older skeletal muscleBackground
Age‐related sarcopenia is accelerated by physical inactivity. Low‐load resistance exercise (LLRE) counters inactivity‐induced muscle atrophy in older adults, but changes in muscle fibre morphology are unstudied. We aimed to determine the impact of LLRE during short‐term inactivity (step‐reduction) on muscle fibre size and capillarity as well as satellite cell (SC) content in older skeletal muscle.
Fourteen older (~71 years) male adults underwent 14 days of step reduction (<1500 steps/day) while performing six sessions of LLRE (~30% maximal strength) with one leg (SR + EX) while the contralateral leg served as an untrained control (SR). Seven healthy ambulatory age‐matched male adults (~69 years) served as a comparator group (COM). Muscle biopsies were taken from the vastus lateralis after 14 days, and immunohistochemical analysis was performed to determine muscle fibre cross‐sectional area (CSA), myonuclear content, SC content (PAX7+ cells), and total (C:F) and fibre type‐specific (C:Fi) capillary‐to‐fibre ratios.
Type I and II fibre CSA was greater in SR + EX compared with SR. Whereas there were no differences across fibre types between SR + EX and CON, type II fibre CSA was significantly lower in SR compared with COM. Type II myonuclear domain was greater in SR + EX compared with COM and SR. Pax7+ cells associated with type I and II fibres were lower in SR compared with SR + EX. Type II PAX7+ cells were also lower in SR compared with COM with a similar trend for type I fibres. There were trends for a lower C:Fi in SR compared with SR + EX for both fibre types with no differences for each compared with COM.
Minimal LLRE during a period of decreased physical activity is associated with greater muscle fibre CSA, SC content, and capillarization. These results support the use of LLRE as an effective countermeasure to inactivity‐induced alterations in muscle morphology with age.
Moore, D. R., Kelly, R. P., Devries, M. C., Churchward‐Venne, T. A., Phillips, S. M., Parise, G., and Johnston, A. P. (2018) Low‐load resistance exercise during inactivity is associated with greater fibre area and satellite cell expression in older skeletal muscle. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12306.
Article first published online: 26 MAR 2018
Aiqing Zhang, Min Li, Bin Wang, Janet D. Klein, S. Russ Price, Xiaonan H. Wang
miRNA-23a/27a attenuates muscle atrophy and renal fibrosis through muscle-kidney crosstalkBackground
The treatment of muscle wasting is accompanied by benefits in other organs, possibly resulting from muscle–organ crosstalk. However, how the muscle communicates with these organs is less understood. Two microRNAs (miRs), miR-23a and miR-27a, are located together in a gene cluster and regulate proteins that are involved in the atrophy process. MiR-23a/27a has been shown to reduce muscle wasting and act as an anti-fibrotic agent. We hypothesized that intramuscular injection of miR-23a/27a would counteract both muscle wasting and renal fibrosis lesions in a streptozotocin-induced diabetic model.
We generated an adeno-associated virus (AAV) that overexpresses the miR-23a~27a~24-2 precursor RNA and injected it into the tibialis anterior muscle of streptozotocin-induced diabetic mice. Muscle cross-section area (immunohistology plus software measurement) and muscle function (grip strength) were used to evaluate muscle atrophy. Fibrosis-related proteins were measured by western blot to monitor renal damage. In some cases, AAV-GFP was used to mimic the miR movement in vivo, allowing us to track organ redistribution by using the Xtreme Imaging System.
The injection of AAV-miR-23a/27a increased the levels of miR-23a and miR-27a as well as increased phosphorylated Akt, attenuated the levels of FoxO1 and PTEN proteins, and reduced the abundance of TRIM63/MuRF1 and FBXO32/atrogin-1 in skeletal muscles. It also decreased myostatin mRNA and protein levels as well as the levels of phosphorylated pSMAD2/3. Provision of miR-23a/27a attenuates the diabetes-induced reduction of muscle cross-sectional area and muscle function. Curiously, the serum BUN of diabetic animals was reduced in mice undergoing the miR-23a/27a intervention. Renal fibrosis, evaluated by Masson trichromatic staining, was also decreased as were kidney levels of phosphorylated SMAD2/3, alpha smooth muscle actin, fibronectin, and collagen. In diabetic mice injected intramuscularly with AAV-GFP, GFP fluorescence levels in the kidneys showed linear correlation with the levels in injected muscle when examined by linear regression. Following intramuscular injection of AAV-miR-23a~27a~24-2, the levels of miR-23a and miR-27a in serum exosomes and kidney were significantly increased compared with samples from control virus-injected mice; however, no viral DNA was detected in the kidney.
We conclude that overexpression of miR-23a/27a in muscle prevents diabetes-induced muscle cachexia and attenuates renal fibrosis lesions via muscle–kidney crosstalk. Further, this crosstalk involves movement of miR potentially through muscle originated exosomes and serum distribution without movement of AAV. These results could provide new approaches for developing therapeutic strategies for diabetic nephropathy with muscle wasting.
Zhang, A., Li, M., Wang, B., Klein, J. D., Price, S. R., and Wang, X. H. (2018) miRNA-23a/27a attenuates muscle atrophy and renal fibrosis through muscle-kidney crosstalk. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12296.
Article first published online: 2 APR 2018
Hsin-Hsiung Chen, Li-Kai Tsai, Kuan-Yu Liao, Tung-Chien Wu, Yun-Hsin Huang, Yuan-Chun Huang, Szu-Wei Chang, Pei-Yu Wang, Yeou-Ping Tsao, Show-Li Chen
Muscle-restricted nuclear receptor interaction protein knockout causes motor neuron degeneration through down-regulation of myogenin at the neuromuscular junctionBackground
Nuclear receptor interaction protein (NRIP) is a calcium/calmodulin (CaM) binding protein. Nuclear receptor interaction protein interacts with CaM to activate calcineurin and CaMKII signalling. The conventional NRIP knockout mice (global knockout) showed muscular abnormality with reduction of muscle oxidative functions and motor function defects.
To investigate the role of NRIP on neuromuscular system, we generated muscle-restricted NRIP knockout mice [conditional knockout (cKO)]. The muscle functions (including oxidative muscle markers and muscle strength) and lumbar motor neuron functions [motor neuron number, axon denervation, neuromuscular junction (NMJ)] were tested. The laser-captured microdissection at NMJ of skeletal muscles and adenovirus gene therapy for rescued effects were performed.
The cKO mice showed muscular abnormality with reduction of muscle oxidative functions and impaired motor performances as global knockout mice. To our surprise, cKO mice also displayed motor neuron degeneration with abnormal architecture of NMJ. Specifically, the cKO mice revealed reduced motor neuron number with small neuronal size in lumbar spinal cord as well as denervating change, small motor endplates, and decreased myonuclei number at NMJ in skeletal muscles. To explore the mechanisms, we screened various muscle-derived factors and found that myogenin is a potential candidate that myogenin expression was lower in skeletal muscles of cKO mice than wild-type mice. Because NRIP and myogenin were colocalized around acetylcholine receptors at NMJ, we extracted RNA from synaptic and extrasynaptic regions of muscles using laser capture microdissection and showed that myogenin expression was especially lower at synaptic region in cKO than wild-type mice. Notably, overexpression of myogenin using intramuscular adenovirus encoding myogenin treatment rescued abnormal NMJ architecture and preserved motor neuron death in cKO mice.
In summary, we demonstrated that deprivation of NRIP decreases myogenin expression at NMJ, possibly leading to abnormal NMJ formation, denervation of acetylcholine receptor, and subsequent loss of spinal motor neuron. Overexpression of myogenin in cKO mice can partially rescue abnormal NMJ architecture and motor neuron death. Therefore, muscular NRIP is a novel trophic factor supporting spinal motor neuron via stabilization of NMJ by myogenin expression.
Chen, H.-H., Tsai, L.-K., Liao, K.-Y., Wu, T.-C., Huang, Y.-H., Huang, Y.-C., Chang, S.-W., Wang, P.-Y., Tsao, Y.-P., and Chen, S.-L. (2018) Muscle-restricted nuclear receptor interaction protein knockout causes motor neuron degeneration through down-regulation of myogenin at the neuromuscular junction. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12299.
Article first published online: 22 MAY 2018
Aldo Scafoglieri, Jan Pieter Clarys
Scafoglieri, A., and Clarys, J. P. (2018) Dual energy X‐ray absorptiometry: gold standard for muscle mass?. Journal of Cachexia, Sarcopenia and Muscle, doi: 10.1002/jcsm.12308.
Article first published online: 14 August 2018
Fanny Buckinx, Francesco Landi, Matteo Cesari, Roger A. Fieding, Marjolein Visser, Klaus Engelke, Stefania Maggi, Elaine Dennison, Nasser M. Al‐Daghri, Sophie Allepaerts, Jurgen Bauer, Ivan Bautmans, Maria Luisa Brandi, Olivier Bruyère, Tommy Cederholm, Francesca Cerreta, Antonio Cherubini, Cyrus Cooper, Alphonso Cruz‐Jentoft, Eugene McCloskey, Bess Dawson‐Hughes, Jean‐Marc Kaufman, Andrea Laslop, Jean Petermans, Jean‐Yves Reginster, René Rizzoli, Sian Robinson, Yves Rolland, Ricardo Rueda, Bruno Vellas, John A. Kanis
The Authors reply: “Dual energy X‐ray absorptiometry: gold standard for muscle mass?” by Scafoglieri et al.
No abstract is available for this article.
Buckinx, F., Landi, F., Cesari, M., Fieding, R. A., Visser, M., Engelke, K., Maggi, S., Dennison, E., Al‐Daghri, N. M., Allepaerts, S., Bauer, J., Bautmans, I., Brandi, M. L., Bruyère, O., Cederholm, T., Cerreta, F., Cherubini, A., Cooper, C., Cruz‐Jentoft, A., McCloskey, E., Dawson‐Hughes, B., Kaufman, J.‐M., Laslop, A., Petermans, J., Reginster, J.‐Y., Rizzoli, R., Robinson, S., Rolland, Y., Rueda, R., Vellas, B., and Kanis, J. A. (2018) The Authors reply: “Dual energy X‐ray absorptiometry: gold standard for muscle mass?” by Scafoglieri et al. Journal of Cachexia, Sarcopenia and Muscle, 9: 788–790. https://doi.org/10.1002/jcsm.12329.