Increased skeletal intermuscular fat is associated with reduced exercise capacity in cancer survivors: a cross-sectional study

The utility of a portable muscle ultrasound in the assessment of muscle alterations in children with acute lymphoblastic leukaemia

BACKGROUND

During treatment for acute lymphoblastic leukaemia (ALL), children are prone to musculoskeletal deterioration. However, non-invasive tools to measure muscle mass and intramuscular alterations are limited. In this study we explored the feasibility of muscle ultrasound in children with ALL. Additionally, we analysed whether automated ultrasound outcomes of muscle size and intramuscular fat infiltration (IMAT) were associated with appendicular skeletal muscle mass (ASMM), muscle strength and physical performance.

METHODS

Children with ALL, aged 3-18 years were included during maintenance therapy. Bilateral images of the rectus femoris muscle were captured using a portable linear array transducer connected to a tablet. Subsequently, an automated image annotation software (MuscleSound) was used to estimate cross-sectional area, muscle thickness and IMAT. Feasibility was assessed using acceptance (percentage of children approached who were enrolled), practicality (percentage of children that completed the ultrasound measurement after enrolment) and implementation (percentage of children that had sufficient imaging to be processed and analysed by the software). Assessments of ASMM by bioimpedance analysis, muscle strength using handheld dynamometry and timed physical performance tests were administered at the same visit. Multivariable linear models were estimated to study the associations between muscle ultrasound outcomes and ASMM, strength and physical performance, adjusted for sex, age, body mass index and ALL treatment week.

RESULTS

Muscle ultrasound was performed in 60 out of 73 invited patients (76.9%), of which 37 were boys (61.7%), and median age was 6.1 years (range: 3-18.8 years). The acceptance was 98.7%, practicality 77.9% and implementation was 100%. Patients who refused the examination (n = 13) were younger (median: 3.6, range: 3-11.2 years) compared with the 60 examined children (P = 0.0009). In multivariable models, cross-sectional area was associated with ASMM (β = 0.49 Z-score, 95% confidence interval [CI]:0.3,2.4), knee-extension strength (β = 16.9 Newton [N], 95% CI: 4.8, 28.9), walking performance (β = -0.46 s, 95% CI: -0.75, -0.18) and rising from the floor (β = -1.07 s, 95% CI: -1.71, -0.42). Muscle thickness was associated with ASMM (β = 0.14 Z-score, 95% CI: 0.04, 0.24), knee-extension strength (β = 4.73 N, 95% CI: 0.99, 8.47), walking performance (β = -0.13 s, 95% CI: -0.22, -0.04) and rising from the floor (β = -0.28 s, 95% CI: -0.48, -0.08). IMAT was associated with knee-extension strength (β = -6.84 N, 95% CI: -12.26, -1.41), walking performance (β = 0.2 s, 95% CI: 0.08, 0.32) and rising from the floor (β = 0.54 s, 95% CI: 0.27, 0.8). None of the muscle ultrasound outcomes was associated with handgrip strength.

CONCLUSIONS

Portable muscle ultrasound appears a feasible and useful tool to measure muscle size and intramuscular alterations in children with ALL. Validation studies using magnetic resonance imaging (gold standard) are necessary to confirm accuracy in paediatric populations.

Efficacy of exercise interventions for women during and after gynaecological cancer treatment - a systematic scoping review

PURPOSE

To systematically synthesise evidence of exercise intervention efficacy for physical/psychosocial outcomes that matter to women during/following treatment for gynaecological cancer.

METHODS

Five databases were searched (PubMed, EMBASE, CINAHL, PsychInfo, Scopus). Exercise-only intervention studies that included women during/ following treatment for any gynaecological cancer, with/ without control comparison, on any physical or psychosocial outcome(s), were included and qualitatively appraised using the Revised Cochrane Risk of Bias tool and a modified Newcastle-Ottawa Scale.

RESULTS

Seven randomised controlled trials (RCTs), three single-arm pre-post studies, and one prospective cohort study satisfied were included (11 studies). Most studies were completed following treatment (91%), included combined (aerobic and resistance; 36%) and aerobic (36%) training, were fully/mostly (63%) unsupervised, and had a moderate-to-high risk of bias. Overall, 33 outcomes (64% objectively-measured) were assessed. Improvements were observed in aerobic capacity (V̇O₂ Peak +1.6 mL/kg/min, 6-minute walk distance +20-27 m), lower- (30-second sit-to-stand +2-4 repetitions) and upper-limb strength (30-second arm curl +5 repetitions; 1RM grip strength/chest press +2.4-3.1 kg), and agility (timed up-and-go -0.6 seconds). However, changes in quality of life, anthropometry/body composition, balance and flexibility were inconsistent. There was no evidence to support worsening of outcomes.

CONCLUSION

Preliminary research into the role of exercise post-gynaecological cancer suggests an improvement in exercise capacity, muscular strength, and agility which, in the absence of exercise, typically decline following gynaecological cancer. Future exercise trials involving larger and more diverse gynaecological cancer samples will improve understanding of the potential and magnitude of effect of guideline-recommended exercise on outcomes that matter to patients.

Lactiplantibacillus plantarum fermented barley extracts ameliorate high-fat-diet-induced muscle dysfunction via mitophagy

BACKGROUND

A reduced level of fatty acid oxidation (FAO) by skeletal muscle leads to the accumulation of intermuscular fat (IMF), which is linked to impaired exercise capacity. Previously, we have reported that Lactiplantibacillus plantarum fermented barley extract (LFBE) has effective anti-obesity properties. In this study, the effects of LFBE on muscle were investigated.

RESULTS

LFBE improved running endurance and muscle strength, which was caused by the elevation of FAO in muscle. In addition, LFBE renovated muscle regeneration through the upregulation of paired box 7 and myogenic differentiation 1 expression avoiding the injury of skeletal muscle fibers. Furthermore, total polyphenol isolated from LFBE (FTP) reinforced mobility and showed a significant protective effect on maintaining muscle fiber morphogenesis in Caenorhabditis elegans. Transmission electron microscope observation suggested FTP induced mitophagy in C. elegans body wall muscle, which was strongly connected with enhanced FAO in mitochondria.

CONCLUSIONS

Our findings highlighted the beneficial bioactivities of FTP and its potential application for stimulating mitophagy and muscle function in obese individuals. © 2022 Society of Chemical Industry.

Skeletal Muscle Deconditioning in Breast Cancer Patients Undergoing Chemotherapy: Current Knowledge and Insights From Other Cancers

Breast cancer represents the most commonly diagnosed cancer while neoadjuvant and adjuvant chemotherapies are extensively used in order to reduce tumor development and improve disease-free survival. However, chemotherapy also leads to severe off-target side-effects resulting, together with the tumor itself, in major skeletal muscle deconditioning. This review first focuses on recent advances in both macroscopic changes and cellular mechanisms implicated in skeletal muscle deconditioning of breast cancer patients, particularly as a consequence of the chemotherapy treatment. To date, only six clinical studies used muscle biopsies in breast cancer patients and highlighted several important aspects of muscle deconditioning such as a decrease in muscle fibers cross-sectional area, a dysregulation of protein turnover balance and mitochondrial alterations. However, in comparison with the knowledge accumulated through decades of intensive research with many different animal and human models of muscle atrophy, more studies are necessary to obtain a comprehensive understanding of the cellular processes implicated in breast cancer-mediated muscle deconditioning. This understanding is indeed essential to ultimately lead to the implementation of efficient preventive strategies such as exercise, nutrition or pharmacological treatments. We therefore also discuss potential mechanisms implicated in muscle deconditioning by drawing a parallel with other cancer cachexia models of muscle wasting, both at the pre-clinical and clinical levels.

Intermuscular fat density as a novel prognostic factor in breast cancer patients treated with adjuvant chemotherapy

BACKGROUND

Body composition, including sarcopenia and fat parameters, has received much attention as a prognostic factor in breast cancer.

METHODS

A total of 479 breast cancer patients who underwent surgery and received adjuvant chemotherapy were enrolled in this study. Body composition, including the index and density of skeletal muscle, visceral fat, subcutaneous fat, and intermuscular fat calculated by CT scan, was used as a prognostic factor. The endpoints were breast cancer-specific survival (BCSS) and overall survival (OS).

RESULTS

The number of patients with stages I, II, and III was 146 (30.5%), 237 (49.5%), and 96 (20%), respectively. Sarcopenia and muscle density were not significant prognostic factors for BCSS and OS. A high visceral fat index (VFI) was an independent prognostic factor for BCSS (HR, 2.55; 95% CI 1.10-5.95, p = 0.03) and OS (HR 2.55, 95% CI 1.26-5.16, p = 0.01). In addition, high intermuscular fat density (IMFD) was also a significant prognostic factor for BCSS (HR, 2.95; 95% CI 1.34-6.46, p = 0.007) and OS (HR 2.28, 95% CI 1.22-4.26, p = 0.01) in multivariate analysis.

CONCLUSION

VFI and IMFD were significant prognostic factors for BCSS and OS in breast cancer patients treated with adjuvant chemotherapy.

Cardiac and skeletal muscle predictors of impaired cardiorespiratory fitness post-anthracycline chemotherapy for breast cancer

This study aimed to characterize peak exercise cardiac function and thigh muscle fatty infiltration and their relationships with VO₂peak among anthracycline-treated breast cancer survivors (BCS). BCS who received anthracycline chemotherapy ~ 1 year earlier (n = 16) and matched controls (matched-CON, n = 16) were enrolled. Resting and peak exercise cardiac function, myocardial T₁ mapping (marker of fibrosis), and thigh muscle fat infiltration were assessed by magnetic resonance imaging, and VO₂peak by cycle test. Compared to matched-CON, BCS had lower peak SV (64 ± 9 vs 57 ± 10 mL/m², p = 0.038), GLS (− 30.4 ± 2.2 vs − 28.0 ± 2.5%, p = 0.008), and arteriovenous oxygen difference (16.4 ± 3.6 vs 15.2 ± 3.9 mL/100 mL, p = 0.054). Mediation analysis showed: (1) greater myocardial T₁ time (fibrosis) is inversely related to cardiac output and end-systolic volume exercise reserve; (2) greater thigh muscle fatty infiltration is inversely related to arteriovenous oxygen difference; both of which negatively influence VO₂peak. Peak SV (R² = 65%) and thigh muscle fat fraction (R² = 68%) were similarly strong independent predictors of VO₂peak in BCS and matched-CON combined. Post-anthracyclines, myocardial fibrosis is associated with impaired cardiac reserve, and thigh muscle fatty infiltration is associated with impaired oxygen extraction, which both contribute to VO₂peak.

Thermoregulation is not impaired in breast cancer survivors during moderate-intensity exercise performed in warm and hot environments

This study aimed to assess how female breast cancer survivors (BCS) respond physiologically, hematologically, and perceptually to exercise under heat stress compared to females with no history of breast cancer (CON). Twenty-one females (9 BCS and 12 CON [age; 54 ± 7 years, stature; 167 ± 6 cm, body mass; 68.1 ± 7.62 kg, and body fat; 30.9 ± 3.8%]) completed a warm (25℃, 50% relative humidity, RH) and hot (35℃, 50%RH) trial in a repeated-measures crossover design. Trials consisted of 30 min of rest, 30 min of walking at 4 metabolic equivalents, and a 6-minute walk test (6MWT). Physiological measurements (core temperature (Tre ), skin temperature (Tskin ), heart rate (HR), and sweat analysis) and perceptual rating scales (ratings of perceived exertion, thermal sensation [whole body and localized], and thermal comfort) were taken at 5- and 10-min intervals throughout, respectively. Venous blood samples were taken before and after to assess; IL-6, IL-10, CRP, IFN-γ, and TGF-β1 . All physiological markers were higher during the 35 versus 25℃ trial; Tre (~0.25℃, p = 0.002), Tskin (~3.8℃, p < 0.001), HR (~12 beats·min-1 , p = 0.023), and whole-body sweat rate (~0.4 L·hr-1 , p < 0.001), with no difference observed between groups in either condition (p > 0.05). Both groups covered a greater 6MWT distance in 25 versus 35℃ (by ~200 m; p = 0.003). Nevertheless, the control group covered more distance than BCS, regardless of environmental temperature (by ~400 m, p = 0.03). Thermoregulation was not disadvantaged in BCS compared to controls during moderate-intensity exercise under heat stress. However, self-paced exercise performance was reduced for BCS regardless of environmental temperature.

Effects of 16 Weeks of Resistance Training on Muscle Quality and Muscle Growth Factors in Older Adult Women with Sarcopenia: A Randomized Controlled Trial

This study examined the effects of resistance training on muscle quality, muscle growth factors, and functional fitness in older adult women with sarcopenia. Twenty-two older adult women aged over 65 with sarcopenia were randomly assigned to either resistance training (RT, n = 12) or non-exercise control group (CG, n = 10). The body weight-based and elastic band RT were performed three times a week, 60 min per session, for 16 weeks. Body composition and thigh muscle quality were estimated by dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT), respectively. The muscle growth factors, including growth differentiation factor-8 (GDF-8), growth differentiation factor-15 (GDF-15), activin A, and follistatin, were analyzed via blood samples. Statistical analyses were performed using repeated measures multivariate analysis of variance (MANOVA), analysis of variance (ANOVA), and effect size (i.e., cohen’s d, partial eta square), and the significance level was set at 0.05. The RT group improved their functional fitness, grip strength, gait speed, and isometric muscle strength (p < 0.01, d > 0.99; large), while these variables did not change in the CG. An increase in intramuscular fat was only observed in the CG (p < 0.01, 1.06; large). Muscle growth factors such as follistatin were significantly increased in the RT (p < 0.05, 0.81; large), but other variables did not change following resistance training. Sixteen weeks of resistance training improved functional fitness and prevented age-related increases in intramuscular fat in the thigh area. However, there were only some changes in muscle growth factors, such as follistatin, suggesting that the effectiveness of resistance training on muscle growth factors is limited. Body weight-based and elastic band resistance training is an alternative training method for sarcopenia to minimize the age-related adverse effects on muscle function and quality.

Exercise, cancer and cardiovascular disease: what should clinicians advise?

Cardiovascular disease is one of the leading causes of morbidity and mortality in persons with cancer. The elevated risk is thought to derive from the combination of cardiovascular risk factors and direct cardiotoxicity from cancer therapies. Exercise may be a potential strategy to counteract these toxicities and maintain cardiovascular reserve. In this article, we review the evidence for the potential cardioprotective effects of exercise training in cancer patients before, during, and following treatment. We also propose a patient-tailored approach for the development of targeted prescriptions based on individual exercise capacity and cardiovascular reserve.

Both intermuscular fat and LVEF decline promote heart failure symptoms in cancer survivors

Background

Approximately 20% of cancer survivors treated with chemotherapy experience worsening heart failure (HF) symptoms post-cancer treatment. While research has predominantly investigated the role of cardiotoxic treatments, much less attention has focused on other risk factors, such as adiposity. However, emerging data in cancer survivors indicates that adiposity may also impact a variety of cardiovascular outcomes. Methods: In a prospective study of 62 patients diagnosed with cancer followed for 24 months from cancer diagnosis through to survivorship (post-cancer treatment), we ascertained baseline fat depots including intermuscular fat (IMF) of the erector spinae muscles; and pre- and post-cancer treatment left ventricular ejection fraction (LVEF) and HF symptoms at baseline and 24-months, respectively. Linear regression was used to model independent variables in relation to HF symptoms at 24-months.

Results

Baseline IMF and LVEF change over 24-months significantly interacted to predict HF score at 24-months. The highest HF symptom score was observed for participants who experienced high IMF at baseline and a high decline in LVEF over 24-months (HF score = 11.0) versus all other categories of baseline IMF and LVEF change.

Conclusions

Together IMF and LVEF decline may play an important role in the worsening of HF symptoms in cancer survivors. The finding that IMF at cancer diagnosis led to elevated HF scores post-treatment suggests that IMF may be a potential target for intervention studies.

Exercise Cardiovascular Magnetic Resonance: A Review

While pharmacologic stress cardiovascular magnetic resonance imaging (MRI) is a robust noninvasive tool in the diagnosis and prognostication of epicardial coronary artery disease, clinical guidelines recommend exercise-based testing in those patients who can exercise. This review describes the development of exercise cardiovascular MRI protocols, summarizes the insights across various patient populations, and highlights future research initiatives. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.

Sodium nitrate co-supplementation does not exacerbate low dose metronomic doxorubicin-induced cachexia in healthy mice

The purpose of this study was to determine whether (1) sodium nitrate (SN) treatment progressed or alleviated doxorubicin (DOX)-induced cachexia and muscle wasting; and (2) if a more-clinically relevant low-dose metronomic (LDM) DOX treatment regimen compared to the high dosage bolus commonly used in animal research, was sufficient to induce cachexia in mice. Six-week old male Balb/C mice (n = 16) were treated with three intraperitoneal injections of either vehicle (0.9% NaCl; VEH) or DOX (4 mg/kg) over one week. To test the hypothesis that sodium nitrate treatment could protect against DOX-induced symptomology, a group of mice (n = 8) were treated with 1 mM NaNO₃ in drinking water during DOX (4 mg/kg) treatment (DOX + SN). Body composition indices were assessed using echoMRI scanning, whilst physical and metabolic activity were assessed via indirect calorimetry, before and after the treatment regimen. Skeletal and cardiac muscles were excised to investigate histological and molecular parameters. LDM DOX treatment induced cachexia with significant impacts on both body and lean mass, and fatigue/malaise (i.e. it reduced voluntary wheel running and energy expenditure) that was associated with oxidative/nitrostative stress sufficient to induce the molecular cytotoxic stress regulator, nuclear factor erythroid-2-related factor 2 (NRF-2). SN co-treatment afforded no therapeutic potential, nor did it promote the wasting of lean tissue. Our data re-affirm a cardioprotective effect for SN against DOX-induced collagen deposition. In our mouse model, SN protected against LDM DOX-induced cardiac fibrosis but had no effect on cachexia at the conclusion of the regimen.

Cardiopulmonary exercise testing - refining the clinical perspective by combining assessments

INTRODUCTION

Cardiorespiratory fitness (CRF) is now established as a vital sign. Cardiopulmonary exercise testing (CPX) is the gold-standard approach to assessing CRF.

AREAS COVERED

A body of literature spanning several decades clearly supports the clinical utility of CPX in those who are apparently health and at risk for chronic disease as well as numerous patient populations. While CPX, in and of itself, is a valid and reliable clinical assessment, combining findings with other available assessments may provide a more comprehensive perspective that enhances clinical decision making and outcomes. The current review will accomplish the following: (1) define key CPX measures based upon current evidence; and (2) describe the current evidence addressing the relationships between CPX and echocardiography, serum biomarkers, and cardiovascular magnetic resonance.

EXPERT OPINION

Cardiopulmonary exercise testing provides prognostic and diagnostic information in apparently healthy individuals, those at risk for one or more chronic conditions, as well as numerous patient populations. Moreover, if the goal of an intervention is to improve one or more systems integral to the physiologic response to exercise, CPX should be considered as a central assessment to gauge therapeutic efficacy. To further refine the information obtained from CPX, combining other assessments has demonstrated promise.

Exercise Intolerance in Anthracycline-Treated Breast Cancer Survivors: The Role of Skeletal Muscle Bioenergetics, Oxygenation, and Composition

BACKGROUND

Peak oxygen consumption (VO₂ ) is reduced in women with a history of breast cancer (BC). We measured leg blood flow, oxygenation, bioenergetics, and muscle composition in women with BC treated with anthracycline chemotherapy (n = 16, mean age: 56 years) and age- and body mass index-matched controls (n = 16).

MATERIALS AND METHODS

Whole-body peak VO₂ was measured during cycle exercise. ³¹ Phosphorus magnetic resonance (MR) spectroscopy was used to measure muscle bioenergetics during and after incremental to maximal plantar flexion exercise (PFE). MR imaging was used to measure lower leg blood flow, venous oxygen saturation (S_v O₂ ), and VO₂ during submaximal PFE, and abdominal, thigh, and lower leg intermuscular fat (IMF) and skeletal muscle (SM).

RESULTS

Whole-body peak VO₂ was significantly lower in BC survivors versus controls (23.1 ± 7.5 vs. 29.5 ± 7.7 mL/kg/minute). Muscle bioenergetics and mitochondrial oxidative capacity were not different between groups. No group differences were found during submaximal PFE for lower leg blood flow, S_v O₂ , or VO₂ . The IMF-to-SM ratio was higher in the thigh and lower leg in BC survivors (0.36 ± 0.19 vs. 0.22 ± 0.07, p = .01; 0.10 ± 0.06 vs. 0.06 ± 0.02, p = .03, respectively) and were inversely related to whole-body peak VO₂ (r = -0.71, p = .002; r = -0.68, p = .003, respectively)_. In the lower leg, IMF-to-SM ratio was inversely related to VO₂ and O₂ extraction during PFE.

CONCLUSION

SM bioenergetics and oxidative capacity in response to PFE are not impaired following anthracycline treatment. Abnormal SM composition (increased thigh and lower leg IMF-to-SM ratio) may be an important contributor to reduced peak VO₂ during whole-body exercise among anthracycline-treated BC survivors.

IMPLICATIONS FOR PRACTICE

Peak oxygen consumption (peak VO₂ ) is reduced in breast cancer (BC) survivors and is prognostic of increased risk of cardiovascular disease-related and all-cause mortality. Results of this study demonstrated that in the presence of deficits in peak VO₂ 1 year after anthracycline therapy, skeletal muscle bioenergetics and oxygenation are not impaired. Rather, body composition deterioration (e.g., increased ratio of intermuscular fat to skeletal muscle) may contribute to reduced exercise tolerance in anthracycline BC survivors. This finding points to the importance of lifestyle interventions including caloric restriction and exercise training to restore body composition and cardiovascular health in the BC survivorship setting.