Novel treatment approaches to cachexia and sarcopenia: highlights from the 5th Cachexia Conference

Combined Exercise Training and Nutritional Interventions or Pharmacological Treatments to Improve Exercise Capacity and Body Composition in Chronic Obstructive Pulmonary Disease: A Narrative Review

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease that is associated with significant morbidity, mortality, and healthcare costs. The burden of respiratory symptoms and airflow limitation can translate to reduced physical activity, in turn contributing to poor exercise capacity, muscle dysfunction, and body composition abnormalities. These extrapulmonary features of the disease are targeted during pulmonary rehabilitation, which provides patients with tailored therapies to improve the physical and emotional status. Patients with COPD can be divided into metabolic phenotypes, including cachectic, sarcopenic, normal weight, obese, and sarcopenic with hidden obesity. To date, there have been many studies performed investigating the individual effects of exercise training programs as well as nutritional and pharmacological treatments to improve exercise capacity and body composition in patients with COPD. However, little research is available investigating the combined effect of exercise training with nutritional or pharmacological treatments on these outcomes. Therefore, this review focuses on exploring the potential additional beneficial effects of combinations of exercise training and nutritional or pharmacological treatments to target exercise capacity and body composition in patients with COPD with different metabolic phenotypes.

The inflammatory response, a mixed blessing for muscle homeostasis and plasticity

Skeletal muscle makes up almost half the body weight of heathy individuals and is involved in several vital functions, including breathing, thermogenesis, metabolism, and locomotion. Skeletal muscle exhibits enormous plasticity with its capacity to adapt to stimuli such as changes in mechanical loading, nutritional interventions, or environmental factors (oxidative stress, inflammation, and endocrine changes). Satellite cells and timely recruited inflammatory cells are key actors in muscle homeostasis, injury, and repair processes. Conversely, uncontrolled recruitment of inflammatory cells or chronic inflammatory processes leads to muscle atrophy, fibrosis and, ultimately, impairment of muscle function. Muscle atrophy and loss of function are reported to occur either in physiological situations such as aging, cast immobilization, and prolonged bed rest, as well as in many pathological situations, including cancers, muscular dystrophies, and several other chronic illnesses. In this review, we highlight recent discoveries with respect to the molecular mechanisms leading to muscle atrophy caused by modified mechanical loading, aging, and diseases. We also summarize current perspectives suggesting that the inflammatory process in muscle homeostasis and repair is a double-edged sword. Lastly, we review recent therapeutic approaches for treating muscle wasting disorders, with a focus on the RANK/RANKL/OPG pathway and its involvement in muscle inflammation, protection and regeneration processes.

A Novel Clinical-Radiomics Model Based on Sarcopenia and Radiomics for Predicting the Prognosis of Intrahepatic Cholangiocarcinoma After Radical Hepatectomy

Background

Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive malignant tumor with a poor prognosis. This study aimed to establish a novel clinical-radiomics model for predicting the prognosis of ICC after radical hepatectomy.

Methods

A clinical-radiomics model was established for 82 cases of ICC treated with radical hepatectomy in our hospital from May 2011 to December 2020. Radiomics features were extracted from venous-phase and arterial-phase images of computed tomography. Kaplan-Meier survival analysis was generated to compare overall survival (OS) between different groups. The independent factors were identified by univariate and multivariate Cox regression analyses. Nomogram performance was evaluated regarding discrimination, calibration, and clinical utility. C-index and area under the curve (AUC) were utilized to compare the predictive performance between the clinical-radiomics model and conventional staging systems.

Results

The radiomics model included five features. The AUC of the radiomics model was 0.817 in the training cohort, and 0.684 in the validation cohort. The clinical-radiomics model included psoas muscle index, radiomics score, hepatolithiasis, carcinoembryonic antigen, and neutrophil/lymphocyte ratio. The reliable C-index of the model was 0.768, which was higher than that of other models. The AUC of the model for predicting OS at 1, and 3 years was 0.809 and 0.886, which was significantly higher than that of the American Joint Committee on Cancer 8^th staging system (0.594 and 0.619), radiomics model (0.743 and 0.770), and tumor differentiation (0.645 and 0.628). After stratification according to the constructed model, the median OS was 59.8 months for low-risk ICC patients and 10.1 months for high-risk patients (p < 0.0001).

Conclusion

The clinical-radiomics model integrating sarcopenia, clinical features, and radiomics score was accurate for prognostic prediction for mass-forming ICC patients. It provided an individualized prognostic evaluation in patients with mass-forming ICC and could helped surgeons with clinical decision-making.

Assessment of sarcopenia as a predictor of poor overall survival for advanced non-small-cell lung cancer patients receiving salvage anti-PD-1 immunotherapy

BACKGROUND

Sarcopenia, which is defined as the loss of skeletal muscle mass, has been identified as a poor prognostic factor for cancer patients. This study sought to elucidate the effects of sarcopenia on the outcomes of advanced non-small cell lung cancer (NSCLC) patients receiving salvage anti-programmed death-1 (PD-1) immunotherapy.

METHODS

In total, 105 NSCLC patients receiving second-line anti-PD-1 immunotherapy at the Sun Yat-sen University Cancer Center between January 2015 and December 2017 were enrolled in this study, and detailed patient data were collected. Available lumbar computed tomography images of the patients were analyzed to determine the total skeletal muscle cross-section area. The efficacy of the predictive and prognostic role of sarcopenia in progression-free survival (PFS) and overall survival (OS) was analyzed using the Kaplan-Meier method, and the risk factors were analyzed using Cox analyses.

RESULTS

We found that patients with sarcopenia receiving salvage anti-PD-1 immunotherapy had significantly worse PFS (2.67 vs. 7.96 months; P<0.001) and OS (9.08 vs. 21.84 months; P<0.001) than their non-sarcopenic counterparts. We also found that sarcopenia was associated with the neutrophil-to-lymphocyte ratio (NLR) (P=0.041), and that the NLR acts as a predictor of OS.

CONCLUSIONS

Sarcopenia was associated with a poor prognosis in advanced NSCLC patients receiving salvage anti-PD-1 immunotherapy. Further research needs to be conducted to identify more biomarkers and the patients most likely to benefit from immunotherapy.

Assessment of sarcopenia as a predictor of poor overall survival for advanced non-small-cell lung cancer patients receiving salvage anti-PD-1 immunotherapy

BACKGROUND

Sarcopenia, which is defined as the loss of skeletal muscle mass, has been identified as a poor prognostic factor for cancer patients. This study sought to elucidate the effects of sarcopenia on the outcomes of advanced non-small cell lung cancer (NSCLC) patients receiving salvage anti-programmed death-1 (PD-1) immunotherapy.

METHODS

In total, 105 NSCLC patients receiving second-line anti-PD-1 immunotherapy at the Sun Yat-sen University Cancer Center between January 2015 and December 2017 were enrolled in this study, and detailed patient data were collected. Available lumbar computed tomography images of the patients were analyzed to determine the total skeletal muscle cross-section area. The efficacy of the predictive and prognostic role of sarcopenia in progression-free survival (PFS) and overall survival (OS) was analyzed using the Kaplan-Meier method, and the risk factors were analyzed using Cox analyses.

RESULTS

We found that patients with sarcopenia receiving salvage anti-PD-1 immunotherapy had significantly worse PFS (2.67 vs. 7.96 months; P<0.001) and OS (9.08 vs. 21.84 months; P<0.001) than their non-sarcopenic counterparts. We also found that sarcopenia was associated with the neutrophil-to-lymphocyte ratio (NLR) (P=0.041), and that the NLR acts as a predictor of OS.

CONCLUSIONS

Sarcopenia was associated with a poor prognosis in advanced NSCLC patients receiving salvage anti-PD-1 immunotherapy. Further research needs to be conducted to identify more biomarkers and the patients most likely to benefit from immunotherapy.

Skeletal muscle atrophy: From mechanisms to treatments

Skeletal muscle is a crucial tissue for movement, gestural assistance, metabolic homeostasis, and thermogenesis. It makes up approximately 40% of the total body weight and 50% of total protein. However, several pathological abnormalities (e.g., chronic diseases, cancer, long-term infection, aging) can induce an imbalance in skeletal muscle protein synthesis and degradation, which triggers muscle wasting and even leads to atrophy. Skeletal muscle atrophy is characterized by weakening, shrinking, and decreasing muscle mass and fiber cross-sectional area at the histological level. It manifests as a reduction in force production, easy fatigue and decreased exercise capability, along with a lower quality of life. Mechanistically, there are several pathophysiological processes involved in skeletal muscle atrophy, including oxidative stress and inflammation, which then activate signal transduction, such as the ubiquitin proteasome system, autophagy lysosome system, and mTOR. Considering the great economic and social burden that muscle atrophy can inflict, effective prevention and treatment strategies are essential but still limited. Exercise is widely acknowledged as the most effective therapy for skeletal muscle atrophy; unfortunately, it is not applicable for all patients. Several active substances for skeletal muscle atrophy have been discovered and evaluated in clinical trials, however, they have not been marketed to date. Knowledge is being gained on the underlying mechanisms, highlighting more promising treatment strategies in the future. In this paper, the mechanisms and treatment strategies for skeletal muscle atrophy are briefly reviewed.

Sarcopenia predicts prognosis of patients with renal cell carcinoma: A systematic review and meta-analysis

Sarcopenia, a concept reflecting the loss of skeletal muscle mass, was reported to be associated with the prognosis of several tumors. However, the prognostic value of sarcopenia in patients with renal cancer remains unclear. We carried out this metaanalysis and systematic review to evaluate the prognostic value of sarcopenia in patients with renal cell carcinomas. We comprehensively searched PubMed, Embase, and Cochrane Library from inception to December 2018. Hazard ratio (HR) and 95% confidence interval (CI) were pooled together. A total of 5 studies consisting of 771 patients were enrolled in this quantitative analysis, 347 (45.0%) of which had sarcopenia. Patients with sarcopenia had a worse OS compared with those without sarcopenia (HR=1.76; 95%CI, 1.35-2.31; P <0.001). In the subgroup of patients with localized and advanced/metastatic diseases, sarcopenia was also associated with poor OS (HR=1.48, P=0.039; HR=2.14, P <0.001; respectively). With a limited sample size, we did not observe difference of PFS between two groups (HR=1.56, 95% CI, 0.69-3.50, P=0.282). In the present meta-analysis, we observed that patients with sarcopenia had a worse OS compared with those without sarcopenia in RCC. Larger, preferably prospective studies, are needed to confirm and update our findings.

Association between temporal muscle thickness and clinical outcomes in patients with newly diagnosed glioblastoma

PURPOSE

Temporal muscle thickness (TMT) has been suggested as a novel biomarker that can represent sarcopenia in head and neck malignancies. This study investigated the association of TMT with clinical outcomes in patients with newly diagnosed glioblastoma (GBM).

METHODS

Using electronic medical records, all GBM patients between 2008 and 2018 at Seoul St. Mary's Hospital were reviewed. Total 177 patients met our eligibility criteria.

RESULTS

The thinner group who had TMT less than the median showed shorter overall survival (OS) and progression-free survival (PFS) than the thicker group who had TMT more than median (OS; 11.0 versus 18.0 months, p < 0.001, and PFS; 6.0 versus 11.0 months, p < 0.001). In the multivariate analysis, the thinner group had negative associations with OS and PFS (OS; HR 2.63 (1.34-2.63), p < 0.001, and PFS; HR 2.21 (1.34-2.50), p = 0.002). We also performed propensity score matching between the thinner and thicker groups to minimize the potential bias. The thinner group showed shorter OS and PFS (OS; 13.5 versus 19.0 months, p = 0.006, and PFS; 6.5 versus 9.0 months, p = 0.028) and had negative associations with OS and PFS than the thicker group (OS; HR 1.90 (1.19-3.03), p = 0.008, and PFS; HR 1.70 (1.07-2.70), p = 0.026) in matched patients.

CONCLUSION

Our findings suggest that TMT can be a useful prognostic biomarker for clinical outcomes in GBM patients. Further preclinical and clinical studies could help elucidate this association of sarcopenia with clinical outcomes in GBM patients.

The prognostic value of sarcopenia combined with hepatolithiasis in intrahepatic cholangiocarcinoma patients after surgery: A prospective cohort study

INTRODUCTION

Intrahepatic Cholangiocarcinoma (ICC) is the second most common primary liver cancer with dismal survival rates. This study aimed to explore the prognostic value of sarcopenia combine with hepatolithiasis in surgically treated ICC patients and develop a prognostic nomogram to help make clinical decisions.

MATERIALS AND METHODS

A prospective cohort study was conducted including patients who underwent hepatectomy for ICC between August 2012 and October 2019. The association between the sarcopenia combined with hepatolithiasis and survival, including overall survival (OS) and recurrence-free survival (RFS) was investigated using the Kaplan-Meier (K-M) method. Univariable and multivariable Cox regression analysis was performed to determine the independent prognostic factors and a nomogram establishment was undertaken based on the multivariable analysis.

RESULTS

A total of 121 ICC patients were included in the study. K-M analysis revealed that ICC patients with sarcopenia and hepatolithiasis have worse OS and RFS than those without sarcopenias and/or hepatolithiasis (p < 0.01). Multivariable analysis showed that age, serum CEA, hepatolithiasis, sarcopenia and diabetes were independent prognostic factors for OS(p < 0.05). Finally, a nomogram with good performance in survival prediction was established (C-index was 0.721; the area under the curve of OS was 0.837). The stratified analysis based on the nomogram disclosed that the median OS was 11.9 months in high-risk patients and 51.2 months in low-risk patients (p < 0.001).

CONCLUSIONS

ICC patients with sarcopenia and hepatolithiasis have worse OS and RFS. The nomogram we developed is a practical tool that can provide a more individualized risk assessment for surgically treated ICC patients.

Sarcopenia as a predictor of mortality in women with breast cancer: a meta-analysis and systematic review

BACKGROUND

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death in women worldwide. Recently, studies have been published with inconsistent findings regarding whether sarcopenia is a risk factor for mortality in breast cancer patients. Therefore, the aim of this systematic review and meta-analysis was to systematically assess and quantify sarcopenia as a risk factor for mortality in breast cancer patients.

METHODS

In a systematic literature review of PubMed, EMBASE, and the Cochrane CENTRAL Library, we searched for observational studies written in English (from database inception until April 30, 2019) that reported an association between sarcopenia and breast cancer in women who were 18 years or older.

RESULTS

A total of six studies (5497 participants) were included in this meta-analysis. Breast cancer patients with sarcopenia were associated with a significantly higher risk of mortality, compared to breast cancer patients without sarcopenia (pooled HR-hazard ratio = 1.71, 95% CI: 1.25-2.33, I2 = 59.1%). In addition, the results of age subgroup analysis showed that participants younger than 55 years with sarcopenia had a lower risk of mortality than participants aged 55 years and older with sarcopenia (pooled HR = 1.46, 95% CI: 1.24-1.72 versus pooled HR = 1.99, 95% CI: 1.05-3.78), whereas both have an increased risk of mortality compared to non-sarcopenic patients. Subgroup analyses regarding stage at diagnosis revealed an increased risk of mortality in non-metastatic patients compared to participants without sarcopenia (pooled HR = 1.91, 95% CI: 1.32-2.78), whereas the association was not significant in metastatic breast cancer patients. Other subgroup analyses were performed using different follow-up periods (> 5 years versus ≤5 years) and the results were different (pooled HR = 1.81, 95% CI: 1.23-2.65 versus pooled HR = 1.70, 95% CI: 0.80-3.62).

CONCLUSIONS

The present study found that sarcopenia is a risk factor for mortality among female early breast cancer patients. It is imperative that more research into specific interventions aimed at treating sarcopenia be conducted in the near future in order to provide evidence which could lead to decreased mortality rates in breast cancer patients.

Sarcopenic Obesity Is Associated with Severe Postoperative Complications in Gastric Cancer Patients Undergoing Gastrectomy: a Prospective Study

OBJECTIVE

This study aimed to determine the risk of severe postoperative complications (SPCs) in patients with gastric cancer and to construct a nomogram based on independently related factors to identify high-risk patients.

METHODS

We conducted a prospective study of 636 consecutive patients with gastric cancer who underwent radical gastrectomy. Degrees of sarcopenia and obesity were calculated before surgery. Factors contributing to SPCs were determined using univariate and multivariate analysis. A nomogram consisting of the independent risk factors was constructed to quantify the individual risk of SPCs.

RESULTS

Logistic analysis revealed that sarcopenic obesity, age, open surgery, and combined resection were independent prognostic factors for SPCs. Sarcopenic obese patients have the highest risk in all patients (sarcopenic obesity vs normal, OR = 6.575 p = 0.001; sarcopenic obesity vs obesity, OR = 5.833 p = 0.001; sarcopenic obesity vs sarcopenia, OR = 2.571 p = 0.032), while obese patients share the similar rate of SPCs with normal people (obesity vs normal, OR = 1.056 p = 0.723). The nomogram we constructed was able to quantify the risk of SPCs reliably (c-index, 0.737).

CONCLUSIONS

Sarcopenic obesity, together with age, open surgery, and combined resection are independent predictors of SPCs. Obesity will significantly increase the risk of SPCs in sarcopenic patient with gastric cancer, but it will not bring higher risk to normal patients. Our nomogram is a simple and practical instrument to identify patients at high risk of surgical complications.

Impact of poor muscle strength on clinical and service outcomes of older people during both acute illness and after recovery

Background

Although Low muscle strength is an important predictor of functional decline in older people, however information on its impact on clinical and service outcomes in acute care settings is still lacking. The aim of this study is to measure the impact of low muscle strength on clinical and service outcomes in older adults during both acute illness and recovery.

Methods

Randomly selected 432 hospitalised older patients had their clinical characteristics and nutritional status assessed within 72 h of admission, at 6 weeks and at 6 months. Low muscle strength-hand grip was defined using the European Working Group criteria. Health outcome measures including nutritional status, length of hospital stay, disability, discharge destination, readmission and mortality were also measured.

Results

Among the 432 patients recruited, 308 (79%) had low muscle strength at baseline. Corresponding figures at 6 weeks and at 6 months were 140 (73%) and 158 (75%). Patients with poor muscle strength were significantly older, increasingly disabled, malnourished and stayed longer in hospital compared with those with normal muscle strength. A significantly higher number of patients with normal muscle strength discharged home independently compared with those with poor muscle strength (p < 0.05). One-year death rate was lower in patients with normal muscle strength 5(6%), compared with those with poor muscle strength 52(15%), however, results were not statistically significant after adjusting for other poor prognostic indicators [adjusted hazard ratio 0.74 (95% CI: 0.14–3.87), p = 0.722].

Conclusion

Poor muscle strength in older people is associated with poor clinical service outcomes during both acute illness and recovery.

Skeletal Muscle Measures as Predictors of Toxicity, Hospitalization, and Survival in Patients with Metastatic Breast Cancer Receiving Taxane-Based Chemotherapy

PURPOSE

Severe skeletal muscle (SM) loss (sarcopenia) is associated with poor cancer outcomes, including reduced survival and increased toxicity. This study investigates SM measures in metastatic breast cancer (MBC) patients receiving first-line taxane-based chemotherapy and evaluates associations with treatment toxicity and other outcomes.

EXPERIMENTAL DESIGN

Using computerized tomography (CT) images taken for the evaluation of disease burden, skeletal muscle area (SMA), and density (SMD) were measured at the third lumbar vertebrae. Sarcopenia was defined as skeletal muscle index (SMI = SMA/height²) ≤ 41. Skeletal muscle gauge (SMG) was created by multiplying SMI × SMD. Fisher exact tests, t tests, the Kaplan-Meier method, and Cox regression modeling were used.

RESULTS

MBC patients (N = 40), median age 55 (range, 34-80), 58% sarcopenic, median SMG 1296 AU (SD, 522). Grade 3-4 toxicity was found in 57% of sarcopenic versus 18% of non-sarcopenic patients (P = 0.02). Toxicity-related hospitalizations were also higher in sarcopenic patients (39% vs. 0%, P = 0.005) as were any adverse events-defined as any grade 3-4 toxicities, hospitalizations, dose reductions, or dose delay-(74% vs. 35%, P = 0.02). Low SMG was associated with grade 3-4 toxicity (P = 0.04), hospitalization (P = 0.01), and time to treatment failure (for progression or toxicity; P = 0.03). Low SMG had a borderline significant association with any adverse event (P = 0.06) and overall survival (P = 0.07).

CONCLUSIONS

SM measures are associated with toxicity outcomes and survival in MBC patients receiving first-line taxane-based chemotherapy. Further studies are needed to explore how routinely obtained CT scans can be used to individualize dosing and improve treatment planning. Clin Cancer Res; 23(3); 658-65. ©2016 AACR.

Espindolol for the treatment and prevention of cachexia in patients with stage III/IV non-small cell lung cancer or colorectal cancer: a randomized, double-blind, placebo-controlled, international multicentre phase II study (the ACT-ONE trial)

BACKGROUND

Cancer cachexia is a major cause of morbidity and mortality with no widely approved treatment.

METHODS

The ACT-ONE trial is a randomized, double-blind, parallel group, placebo-controlled, phase II multicentre trial in patients (25-80 years) with stages III or IV colorectal cancer or non-small cell lung cancer-related cachexia that tested two doses of espindolol (a novel non-selective β blocker with central 5-HT1a and partial β2 receptor agonist effects). The primary endpoint was the difference in the rate of weight change over 16 weeks (linear mixed-effect model for repeated measures) between high-dose espindolol and placebo.

RESULTS

Eighty-seven patients were randomized centrally in blocks in a ratio 3:2:1 [42 high dose, 10 mg twice daily (bd):31 placebo:14 low dose, 2.5 mg bd]. High-dose espindolol produced a statistically and clinically significant weight gain (+0.54 kg/4 weeks, 95% CI 0.38-0.70) compared with a weight loss on placebo (-0.21 kg/4 weeks, 95% CI -0.37-0.05); P < 0.0001. High-dose espindolol produced a statistically significant increase in lean body mass, whilst changes in fat mass were neutral. Hand grip strength significantly (high dose -1.15 ± 0.7 kg, placebo -3.51 ± 0.8 kg change per 4 weeks; P = 0.0134), stair climbing power, and 6-min walk test non-significantly were all directionally in favour of high-dose espindolol. There were no clinically significant differences in safety signals or survival between treatment groups, although a numerical excess of dyspnoea was seen with high-dose espindolol (19.1%) compared with placebo (3.2%).

CONCLUSIONS

This positive trial showed that espindolol 10 mg bd significantly reversed weight loss, improved fat free mass, and maintained fat mass in advanced colorectal cancer and non-small cell lung cancer-related cachexia. This was associated with a significant improvement in handgrip strength, supporting the further investigation of 10 mg bd espindolol for the treatment of cancer cachexia. Although not powered to look at dose response, most treatment effects for low dose lay between high dose and placebo, suggesting that there may be a dose response in the effects of espindolol.

Prognostic value of sarcopenia in adults with solid tumours: A meta-analysis and systematic review

BACKGROUND

Body composition plays an important role in predicting treatment outcomes in adults with cancer. Using existing computed tomographic (CT) cross-sectional imaging and readily available software, the assessment of skeletal muscle mass to evaluate sarcopenia has become simplified. We performed a systematic review and meta-analysis to quantify the prognostic value of skeletal muscle index (SMI) obtained from cross-sectional CT imaging on clinical outcomes in non-haematologic solid tumours.

METHODS

We searched PubMed and the American Society Clinical Oncology online database of meeting abstracts up to October 2015 for relevant studies. We included studies assessing the prognostic impact of pre-treatment SMI on clinical outcomes in patients with non-haematologic solid tumours. The primary outcome was overall survival (OS) and the secondary outcomes included cancer-specific survival (CSS), disease-free survival (DFS), and progression-free survival (PFS). The summary hazard ratio (HR) and 95% confidence interval (CI) were calculated.

RESULTS

A total of 7843 patients from 38 studies were included. SMI lower than the cut-off was associated with poor OS (HR = 1.44, 95% CI = 1.32-1.56, p < 0.001). The effect of SMI on OS was observed among various tumour types and across disease stages. Worse CSS was also associated with low SMI (HR = 1.93, 95% CI = 1.38-2.70, p < 0.001) as well as DFS (HR = 1.16, 95% CI = 1.00-1.30, p = 0.014), but not PFS (HR = 1.54, 95% CI = 0.90-2.64, p = 0.117).

CONCLUSIONS

This meta-analysis demonstrates that low SMI at cancer diagnosis is associated with worse survival in patients with solid tumours. Further research into understanding and mitigating the negative effects of sarcopenia in adults with cancer is needed.

Highly specific detection of myostatin prodomain by an immunoradiometric sandwich assay in serum of healthy individuals and patients

Background

Myostatin is a muscle derived factor that functions as a negative regulator of skeletal muscle growth. Induction of myostatin expression was observed in rodent models of muscle wasting and in cachectic patients with cancer or pulmonary disease. Therefore, there is an increasing interest to use serum myostatin as a biomarker.

Methods

We established an immunoradiometric sandwich assay (IRMA), which uses a commercially available chicken polyclonal, affinity purified antibody directed against human myostatin prodomain. We determined the serum concentrations of myostatin prodomain in 249 healthy individuals as well as 169 patients with heart failure, 53 patients with cancer and 44 patients with chronic pulmonary disease.

Results

The IRMA had a detection limit of 0.7ng/ml, an intraassay imprecision of ≤14.1% and an interassay imprecision of ≤ 18.9%. The specificity of our assay was demonstrated by size exclusion chromatography, detection of myostatin by Western-blotting and a SMAD-dependent transcriptional-reporter assay in the signal-rich serum fractions, as well as lack of interference by unspecific substances like albumin, hemoglobin or lipids. Myostatin prodomain was stable at room temperature and resistant to freeze-thaw cycles. Apparently healthy individuals over the age of 55 had a median myostatin prodomain serum concentration of 3.9ng/ml (25^th-75^th percentiles, 2-7ng/ml) and we could not detect increased levels in patients with stable chronic heart failure or cancer related weight loss. In contrast, we found strongly elevated concentrations of myostatin prodomain (median 26.9ng/ml, 25^th-75^th percentiles, 7-100ng/ml) in the serum of underweight patients with chronic pulmonary disease.

Conclusions

We established a highly specific IRMA for the quantification of myostatin prodomain concentration in human serum. Our assay could be useful to study myostatin as a biomarker for example in patients with chronic pulmonary disease, as we detected highly elevated myostatin prodomain serum levels in underweight individuals of this group.

The new metabolic treatments for sarcopenia

In terms of managing sarcopenia, many studies have shown that physical activity (in particular resistance exercise) and specific nutrition interventions such as protein and amino acids supplementation can improve muscle mass and strength in older adults. Moreover, several drugs have been suggested to have an impact on muscle outcomes, with various levels of scientific evidence. In the present paper we have reviewed the evidence regarding the effect of some new metabolic agents (vitamin D, leucine, β-hydroxy β-methylbutyrate, citrulline malate, ornithine, isoflavones) on sarcopenia and muscular outcomes in older adults. For each metabolic agent, we have also discussed the biological plausibility of the described effect.

Finding good biomarkers for sarcopenia

The term sarcopenia describes the age-related loss of skeletal muscle mass and function. While this process, in principal, occurs in every adult person and already starts around the age of 40, it is associated with disability, morbidity, and increased mortality in some individuals. In the absence of clear clinical manifestation, we today lack the ability to differentiate between physiological and pathological sarcopenia. In this regard, we need good biomarkers that can be quantified in a reliable, cost-effective manner and that guide diagnosis and therapy of pathological sarcopenia in routine clinical practice and clinical trials. We suggest that a combination of serum markers, diagnostic imaging, and functional tests of muscle function would constitute an ideal biomarker panel. Importantly, sarcopenia biomarkers will have to be tested and validated in clinical trials.

Malnutrition in cirrhosis: contribution and consequences of sarcopenia on metabolic and clinical responses

Malnutrition is the most common, reversible complication of cirrhosis that adversely affects survival, response to other complications, and quality of life. Sarcopenia, or loss of skeletal muscle mass, and loss of adipose tissue and altered substrate use as a source of energy are the 2 major components of malnutrition in cirrhosis. Current therapies include high protein supplementation especially as a late evening snack. Exercise protocols have the potential of aggravating hyperammonemia and portal hypertension. Recent advances in understanding the molecular regulation of muscle mass has helped identify potential novel therapeutic targets including myostatin antagonists, and mTOR resistance.

Molecular mechanisms of cachexia in chronic disease

Cachexia is a metabolic syndrome that manifests with excessive weight loss and disproportionate muscle wasting. It is related to many different chronic diseases, such as cancer, infections, liver disease, inflammatory bowel disease, cardiac disease, chronic obstructive pulmonary disease, chronic renal failure and rheumatoid arthritis. Cachexia is linked with poor outcome for the patients. In this article, we explore the role of the hypothalamus, liver, muscle tissue and adipose tissue in the pathogenesis of this syndrome, particularly concentrating on the role of cytokines, hormones and cell energy-controlling pathways (such as AMPK, PI3K/Akt and mTOR). We also look at possible future directions for therapeutic strategies.

The ACT-ONE trial, a multicentre, randomised, double-blind, placebo-controlled, dose-finding study of the anabolic/catabolic transforming agent, MT-102 in subjects with cachexia related to stage III and IV non-small cell lung cancer and colorectal cancer: study design

AIMS: Cachexia, the wasting disorder associated with a wide range of serious illnesses including cancer, is a major cause of morbidity and mortality. There is currently no widely approved therapeutic agent for treating or preventing cancer-associated cachexia. Colorectal cancer and non-small cell lung cancer have relatively high incidences of cachexia, approximately 28% and 34%, respectively. Neurohormonal overactivity has been implicated in the genesis and progression of cachexia and beta receptor antagonism has been proposed as a potential therapy. MT-102, a novel anabolic/catabolic transforming agent, has a multi-functional effect upon three potential pharmacological targets in cancer cachexia, namely reduced catabolism through non-selective β-blockade, reduced fatigue, and thermogenesis through central 5-HT1a antagonism and increased anabolism through partial β-2 receptor agonism. METHODS: At least 132 male and female patients, aged between 25 and 80 years with a confirmed diagnosis of late-stage non-small cell lung cancer or colorectal cancer, with cachexia will be randomised to either one of the two MT-102 doses or placebo in a 3:1:2 ratio (MT-102 10 mg BD(-1)/MT-102 2.5 mg BD/placebo). Patients will continue on study treatment for maximally 16 weeks. The primary endpoint, to be analysed by assigned treatment group, will be body weight change over 16 weeks. For this endpoint, the study has 85% power (0.05% significance level) to detect per 4-week period a mean change of -0.8 kg in the placebo group and 0 kg in the high-dose MT-102 arm. The first patient was randomised in February 2011 and patient recruitment is expected to continue until mid-2012. PERSPECTIVE: The ACT-ONE trial is designed to test whether the anabolic/catabolic transforming agent MT-102 will positively impact on the rate of change of body weight in cancer cachexia, thereby evaluating a novel therapeutic strategy in this hitherto poorly treatable condition. A separate ACT-TWO trial will recruit patients who complete the ACT-ONE trial and remain on randomised double-blind medication. Participants in ACT-TWO will be followed for an additional period with a separate primary endpoint.

Pathophysiology and treatment options for cardiac anorexia

The anorexia-cachexia syndrome (ACS) occurs in many chronic illnesses, such as cancer, AIDS, and chronic obstructive pulmonary disease in addition to chronic congestive heart failure (CHF). Comparable to other chronic states, the ACS complicates CHF and impacts its prognosis; however, the available treatment options for this syndrome remain unsatisfactory. This review article focuses on the complex pathophysiology of cardiac anorexia. We focus on the recent data demonstrating the relationships between central appetite-regulating structures, inflammatory processes, and neurohormonal activation, and their respective roles in the development of anorexia. We then describe the different treatment options and discuss some future prospects for the management for cardiac anorexia.

Cancer cachexia: mechanisms and clinical implications

Cachexia is a multifactorial process of skeletal muscle and adipose tissue atrophy resulting in progressive weight loss. It is associated with poor quality of life, poor physical function, and poor prognosis in cancer patients. It involves multiple pathways: procachectic and proinflammatory signals from tumour cells, systemic inflammation in the host, and widespread metabolic changes (increased resting energy expenditure and alterations in metabolism of protein, fat, and carbohydrate). Whether it is primarily driven by the tumour or as a result of the host response to the tumour has yet to be fully elucidated. Cachexia is compounded by anorexia and the relationship between these two entities has not been clarified fully. Inconsistencies in the definition of cachexia have limited the epidemiological characterisation of the condition and there has been slow progress in identifying therapeutic agents and trialling them in the clinical setting. Understanding the complex interplay of tumour and host factors will uncover new therapeutic targets.

Current and future pharmacologic treatment of sarcopenia

Sarcopenia is a complex multifactorial condition that can by treated with multimodal approaches. No pharmacologic agent to prevent or treat sarcopenia has been as efficacious as exercise (mainly resistance training) in combination with nutritional intervention (adequate protein and energy intake). However, performing resistance training sessions and following nutritional advice can be challenging, especially for frail, sarcopenic, elderly patients, and results remain only partial. Therefore, new pharmacologic agents may substantially reduce the functional decline in older people. This article reviews the new pharmacologic agents currently being assessed for treating sarcopenia.

Treatment strategies for sarcopenia and frailty

Sarcopenia is the key feature of frailty in older people and a major determinant of adverse health outcomes such as functional limitations and disability. Resistance training and adequate protein and energy intake are the key strategies for the management of sarcopenia. Management of weight loss and resistance training are the most relevant protective countermeasures to slow down the decline of muscle mass and muscle strength. The quality of amino acids in the diet is an important factor for stimulating protein synthesis. Vitamin D deficiency should be treated, and new pharmacologic approaches for sarcopenia are currently assessed.

Myostatin from the heart: local and systemic actions in cardiac failure and muscle wasting

A significant proportion of heart failure patients develop skeletal muscle wasting and cardiac cachexia, which is associated with a very poor prognosis. Recently, myostatin, a cytokine from the transforming growth factor-β (TGF-β) family and a known strong inhibitor of skeletal muscle growth, has been identified as a direct mediator of skeletal muscle atrophy in mice with heart failure. Myostatin is mainly expressed in skeletal muscle, although basal expression is also detectable in heart and adipose tissue. During pathological loading of the heart, the myocardium produces and secretes myostatin into the circulation where it inhibits skeletal muscle growth. Thus, genetic elimination of myostatin from the heart reduces skeletal muscle atrophy in mice with heart failure, whereas transgenic overexpression of myostatin in the heart is capable of inducing muscle wasting. In addition to its endocrine action on skeletal muscle, cardiac myostatin production also modestly inhibits cardiomyocyte growth under certain circumstances, as well as induces cardiac fibrosis and alterations in ventricular function. Interestingly, heart failure patients show elevated myostatin levels in their serum. To therapeutically influence skeletal muscle wasting, direct inhibition of myostatin was shown to positively impact skeletal muscle mass in heart failure, suggesting a promising strategy for the treatment of cardiac cachexia in the future.

Cachexia in heart disease: highlights from the ESC 2010

Cardiac cachexia is a co-morbidity that may develop in terminal stages of chronic heart failure (CHF). Up to 15% of ambulatory patients with heart failure are affected. Over the last decades, cardiac cachexia and alterations in muscle metabolism in heart disease have received increasing research interest. This article highlights some recent studies of cardiac cachexia that were presented at the annual meeting of the European Society of Cardiology in September 2010 in Stockholm, Sweden. Studies presented here were focused on effects of exercise training and protein degradation, particularly into the role of the ubiquitin-proteasome complex and its ubiquitin ligases MuRF-1 and MAFbx. Exercise training in patients with CHF was found to increase maximal oxygen consumption and to reduce MuRF-1 expression. Lysosomal muscle degradation does not seem to play a major role in patients with CHF, however, inflammatory cytokines such as tumor necrosis factor-a trigger muscle protein degradation. Other studies found that the serum levels of the adipokine adiponectin are elevated in patients with CHF and that these levels may be correlated with muscle mass, muscle strength in the arms, or with trunk fat mass. Another study showed that the expression of myostatin in skeletal muscle, a negative regulator of muscle growth that is essential for normal regulation of muscle mass, is decreased in spontaneously hypertensive rats with heart failure compared with control animals. This is also true for follistatin, a powerful antagonist, and its potential as a biomarker of muscle wasting. These findings may pave the way for effective treatment approaches to cardiac cachexia.

Nutritional assessment and support of the patient with acute heart failure

PURPOSE OF REVIEW

A significant number of patients hospitalized with heart failure are malnourished. Depletion of micronutrients, which is known to occur in heart failure for a variety of reasons, may contribute to myocardial abnormalities noted in heart failure. In this review, we focus on nutritional supplementation strategies that might improve myocardial performance and, as a consequence, decrease mortality and morbidity in these patients.

RECENT FINDINGS

The available data suggest that micronutrient and macronutrient supplementation may play a role in improving the myocardial metabolic abnormalities noted in heart failure. A recent trial of omega-3 fatty acid macronutrient supplementation showed a modest decrease in mortality and hospitalizations when used in patients with New York Heart Association class II-IV heart failure.

SUMMARY

Recommendations for nutritional support in patients with heart failure are difficult to make due to a lack of large randomized trials. Supplementation with omega-3 fatty acids, and micronutrients such as thiamine, coenzyme Q-10 and carnitine has shown promise in several studies. Since the data is not conclusive, large trials are needed to address whether these positive findings are reproducible in a wider subset of patients. In addition, these trials should study the combination of different micronutrients and macronutrients since heart failure patients are rarely deficient in just one micronutrient or macronutrient.

Cachexia versus sarcopenia

PURPOSE OF REVIEW

The review summarizes and discusses the proposed new definitions for sarcopenia and cachexia. It also highlights the overlapping of both conditions and the fact that these conditions frequently occur in elderly patients.

RECENT FINDINGS

Sarcopenia is now recognized as a multifactorial geriatric syndrome. Cachexia is defined as a metabolic syndrome in which inflammation is the key feature and so cachexia can be an underlying condition of sarcopenia. Recently, cachexia has been defined as 'a complex metabolic syndrome associated with underlying illness and characterized by loss of muscle mass with or without loss of fat mass. The prominent clinical feature of cachexia is weight loss in adults'. Different recommendations have been proposed for the diagnosis of sarcopenia. At present, all definitions combine an assessment of muscle mass and muscle function (strength or physical performances such as gait speed). However, the relevance and the validation of these evolving definitions need to be assessed in future studies.

SUMMARY

Although the recent definitions of sarcopenia and cachexia boost research in the field and define distinct entities, the cause behind the loss of muscle mass (whether cachexia or sarcopenia) may, however, be indistinguishable in clinical practice. Therefore, new therapeutic approaches, alone or in combination, could be targeted on both conditions.

A systematic review of the role of vitamin insufficiencies and supplementation in COPD

BACKGROUND

Pulmonary inflammation, oxidants-antioxidants imbalance, as well as innate and adaptive immunity have been proposed as playing a key role in the development of COPD. The role of vitamins, as assessed either by food frequency questionnaires or measured in serum levels, have been reported to improve pulmonary function, reduce exacerbations and improve symptoms. Vitamin supplements have therefore been proposed to be a potentially useful additive to COPD therapy.

METHODS

A systematic literature review was performed on the association of vitamins and COPD. The role of vitamin supplements in COPD was then evaluated.

CONCLUSIONS

The results of this review showed that various vitamins (vitamin C, D, E, A, beta and alpha carotene) are associated with improvement in features of COPD such as symptoms, exacerbations and pulmonary function. High vitamin intake would probably reduce the annual decline of FEV1. There were no studies that showed benefit from vitamin supplementation in improved symptoms, decreased hospitalization or pulmonary function.