Pathogenesis and Management of Sarcopenia

Exercise and nutrition benefit skeletal muscle: From influence factor and intervention strategy to molecular mechanism

Sarcopenia is a progressive systemic skeletal muscle disease induced by various physiological and pathological factors, including aging, malnutrition, denervation, and cardiovascular diseases, manifesting as the decline of skeletal muscle mass and function. Both exercise and nutrition produce beneficial effects on skeletal muscle growth and are viewed as feasible strategies to prevent sarcopenia. Mechanisms involve regulating blood flow, oxidative stress, inflammation, apoptosis, protein synthesis and degradation, and satellite cell activation through exerkines and gut microbiomes. In this review, we summarized and discussed the latest progress and future development of the above mechanisms for providing a theoretical basis and ideas for the prevention and treatment of sarcopenia.

NRF2 in age-related musculoskeletal diseases: Role and treatment prospects

The NRF2 pathway is a metabolic- and redox-sensitive signaling axis in which the transcription factor controls the expression of a multitude of genes that enable cells to survive environmental stressors, such as oxidative stress, mainly by inducing the expression of cytoprotective genes. Basal NRF2 levels are maintained under normal physiological conditions, but when exposed to oxidative stress, cells activate the NRF2 pathway, which is crucial for supporting cell survival. Recently, the NRF2 pathway has been found to have novel functions in metabolic regulation and interplay with other signaling pathways, offering novel insights into the treatment of various diseases. Numerous studies have shown that targeting its pathway can effectively investigate the development and progression of age-related musculoskeletal diseases, such as sarcopenia, osteoporosis, osteoarthritis, and intervertebral disc degeneration. Appropriate regulation of the NRF2 pathway flux holds promise as a means to improve musculoskeletal function, thereby providing a new avenue for drug treatment of age-related musculoskeletal diseases in clinical settings. The review summarized an overview of the relationship between NRF2 and cellular processes such as oxidative stress, apoptosis, inflammation, mitochondrial dysfunction, ferroptosis, and autophagy, and explores the potential of targeted NRF2 regulation in the treatment of age-related musculoskeletal diseases.

Impact of sarcopenia on the prognosis of patients with advanced non-small cell lung cancer treated with antiangiogenic therapy: A propensity score matching analysis

BACKGROUND

Limited information is available regarding the impact of sarcopenia on the prognosis of antiangiogenic therapy in individuals with advanced non-small cell lung cancer (NSCLC). This study primarily sought to examine the prognostic significance of sarcopenia in individuals with advanced NSCLC undergoing antiangiogenic therapy.

METHODS

We retrospectively enrolled all patients who met the inclusion and exclusion criteria from 2019 to 2021 at Nantong University Hospital. Patients were grouped according to the presence or absence of sarcopenia. After propensity score matching (PSM), progression-free survival (PFS), overall survival (OS), and adverse event rates were compared between the two groups. Factors associated with prognosis were screened using univariate and multivariate analyses.

RESULTS

A total of 267 patients were included, with a total of 201 matched at baseline after PSM (77 in the sarcopenia group and 124 in the non-sarcopenia group). The sarcopenia group had lower PFS (p = 0.043) and OS (p = 0.011) than the non-sarcopenia group and a higher incidence of adverse events (p = 0.044). Multivariate analysis suggested that sarcopenia is an independent prognostic risk factor for OS in advanced NSCLC patients receiving antiangiogenic therapies (p = 0.009). Results of subgroup analyses showed some differences in the impact of sarcopenia on survival prognosis in populations with different characteristics.

CONCLUSION

Patients with advanced NSCLC with comorbid sarcopenia exhibit a worse prognosis when treated with antiangiogenic therapy, and preventing and ameliorating sarcopenia may lead to better survival outcomes in patients with advanced NSCLC.

Association of head and neck CT-derived sarcopenia with mortality and adverse outcomes: A systematic review

BACKGROUND

There is growing interest in the association of CT-assessed sarcopenia with adverse outcomes in non-oncological settings.

PURPOSE

The aim of this systematic review is to summarize existing literature on the prognostic implications of CT-assessed sarcopenia in non-oncological patients.

MATERIALS AND METHODS

Three independent authors searched Medline/PubMed, Embase and Cochrane Library up to 30 December 2023 for observational studies that reported the presence of sarcopenia defined on CT head and neck in association with mortality estimates and other adverse outcomes, in non-oncological patients. The quality of included studies were assessed using the Quality of Prognostic Studies tool.

RESULTS

Overall, 15 studies (3829 participants) were included. Nine studies were at low risk of bias, and six were at moderate risk of bias. Patient populations included those admitted for trauma or treatment of intracranial aneurysms, ischemic stroke, transient ischemic attack, and intracranial stenosis. Sarcopenia was associated with increased 30-day to 2-year mortality in inpatients and patients undergoing carotid endarterectomy or mechanical thrombectomy for acute ischemic stroke. Sarcopenia was also associated with poorer neurological and functional outcomes, increased likelihood of admission to long-term care facilities, and longer duration of hospital stays. The observed associations of sarcopenia with adverse outcomes remained similar across different imaging modalities and methods for quantifying sarcopenia.

CONCLUSION

CT-assessed sarcopenia was associated with increased mortality and poorer outcomes across diverse patient populations. Measurement and early identification of sarcopenia in vulnerable patients allows for enhanced prognostication, and focused allocation of resources to mitigate adverse outcomes.

Perindopril erbumine-entrapped ultradeformable liposomes alleviate sarcopenia via effective skin delivery in muscle atrophy mouse model

Sarcopenia is a pertinent challenge in the super-aged societies causing reduced functional performance, poor quality of life and increased morbidity. In this study, the potential of perindopril erbumine-loaded ultradeformable liposomes (PE-UDLs) against sarcopenia was investigated. PE-UDLs were prepared by thin-film hydration and extrusion method using egg yolk L-α-phosphatidylcholine (EPC) as a lipid bilayer former and Tween 80 or sodium deoxycholate as an edge activator. Owing to the smallest particle size (75.0 nm) and the highest deformability (54.2) and entrapment efficiency (35.7 %), PE-UDLs with EPC to Tween 80 ratio of 8:2 was selected as the optimized formulation. The optimized PE-UDLs showed substantially higher cumulative amount of drug permeated and permeation rate across the rat skin compared to PE solution (485.7 vs. 50.1 µg and 13.4 vs. 2.3 µg/cm2/h, respectively). Topically applied PE-UDLs successfully ameliorated the effects of lipopolysaccharide (LPS)-induced sarcopenia in mice by improving body weight changes, grip strength and muscle weight. Furthermore, PE-UDLs reduced the shrinkage of muscle fibers as demonstrated by higher cross-sectional area than PE solution. PE-UDLs also increased the expression of myosin heavy chain (MHC) protein and reduced the expression of muscle atrophy F-box (Atrogin-1) and muscle ring-finger protein-1 (MuRF1), thereby improving muscles atrophy. In conclusion, these results demonstrate the therapeutic potential of PE-UDLs against sarcopenia.

Comparison of Shear-Wave Elastography USG and CT: Composition Analysis of Rectus Femoris Muscle in Healthy Adults and Chronic Kidney Disease Patients

PURPOSE

This study aimed to compare shear-wave elastography (SWE) USG and composition analysis of CT on the right mid-rectus femoris muscle (RF) in both healthy adults and chronic kidney disease (CKD) patients.

METHODS

Sixty-three healthy adults and 22 CKD patients were included. One musculoskeletal radiologist performed right RF SWE USG, while two radiologists measured shear-wave velocity (SWV) from the same SWE images. CT scan was performed, and muscle composition was measured using imageJ, categorized into four HU-based compositions. Interobserver agreement for SWV between two readers was evaluated. Correlations between SWV and CT compositions were analyzed using Pearson's or Spearman's correlation.

RESULTS

SWV of healthy group was significantly higher than CKD group by each reader (p = 0.030 and 0.038). The percentage of low-density muscle was higher in CKD group than healthy group (p < 0.001), and the percentage of normal density muscle was higher in healthy group than CKD (p < 0.001) by each reader. Interobserver agreement of SWV by the two readers was almost perfect in both groups (k = 0.957-0.984, 0.959-0.993). There was a statistically significant correlation between SWV and the percentage of normal density muscle on CT in both healthy adults and CKD patient groups (Reader 1, r = 0.318-0.480, p = 0.001 and 0.024; Reader 2, r = 0.511-0.518, p < 0.001 and p = 0.013).

CONCLUSIONS

SWV demonstrated a significant correlation with the percentage of normal density muscle on CT in both healthy adults and CKD patients by each reader. SWE provides a radiation-free approach that may offer an objective method for evaluating muscle quality, potentially making it an option for muscle monitoring.

Rodent model intervention for prevention and optimal management of sarcopenia: A systematic review on the beneficial effects of nutrients & non-nutrients and exercise to improve skeletal muscle health

Sarcopenia is a common musculoskeletal disorder characterized by degenerative processes and is strongly linked to an increased susceptibility to falls, fractures, physical limitations, and mortality. Several models have been used to explore therapeutic and preventative measures as well as to gain insight into the molecular mechanisms behind sarcopenia. With novel experimental methodologies emerging to design foods or novel versions of conventional foods, understanding the impact of nutrition on the prevention and management of sarcopenia has become important. This review provides a thorough assessment of the use of rodent models of sarcopenia for understanding the aging process, focusing the effects of nutrients, plant extracts, exercise, and combined interventions on skeletal muscle health. According to empirical research, nutraceuticals and functional foods have demonstrated potential benefits in enhancing physical performance. In preclinical investigations, the administration of herbal extracts and naturally occurring bioactive compounds yielded advantageous outcomes such as augmented muscle mass and strength generation. Furthermore, herbal treatments exhibited inhibitory effects on muscle atrophy and sarcopenia. A substantial body of information establishes a connection between diet and the muscle mass, strength, and functionality of older individuals. This suggests that nutrition has a major impact in both the prevention and treatment of sarcopenia.

Screening tool for sarcopenia (SARC-F) predicts unsatisfactory medical treatment of lower urinary tract symptoms in elderly men aged 75 years or older: a preliminary observational study

We investigated the influence of sarcopenia on treatment outcomes in elderly patients receiving medical therapy for lower urinary tract symptoms (LUTS). We included male patients with LUTS aged ≥ 75 years who had not changed their medication for 1 year. Current conditions were estimated using IPSS, overactive bladder symptoms score (OABSS), and screening tool for sarcopenia (SARC-F). We also evaluated prostatic volume (PV), serum testosterone level, grip strength, and nutrition status. SARC-F score of ≧4 was defined as sarcopenia. We included 59 patients in this study, including 16 patients (27.1%) with sarcopenia. The mean grip strength was significantly lower in the sarcopenia group than the non-sarcopenia group (25.5 vs. 30 kg, p < 0.01). IPSS total score, voiding symptom score of IPSS, and IPSS-QOL were significantly higher in the sarcopenia group than the non-sarcopenia group. The non-sarcopenia group had significantly larger PV (40 vs. 20 ml, p < 0.01) and higher testosterone levels (497.5 vs. 369 ng/ml, p = 0.03) compared with the sarcopenia group, whereas the percentage of patients taking dutasteride tended to be higher in the non-sarcopenia group than the sarcopenia group (58.1% vs. 31.3%, p = 0.07). Moderate and severe LUTS (IPSS total ≥ 8) persisted in 34 patients (57.6%) after medical treatment. Multivariate analysis showed that only SARC-F was a significant factor affecting the IPSS total ≥ 8 despite medical treatment for 1 year (OR 1.67, 95%CI: 1.13-2.46, p = 0.01). Sarcopenia defined by using SARC-F is a significant factor for unsatisfactory medical treatment of LUTS in elderly men aged ≥ 75 years.

Head and Neck Cancer and Sarcopenia: An Integrative Clinical and Functional Review

Sarcopenia is recognized as a crucial factor impacting the prognosis, treatment responses, and quality of life of HNC patients. This review discusses various mechanisms, including common etiological factors, such as aging, chronic inflammation, and metabolic dysregulation. Cancer-related factors, including tumor locations and treatment modalities, contribute to the development of sarcopenia. The clinical implications of sarcopenia in HNC patients extend beyond reduced muscle strength; it affects overall mobility, reduces quality of life, and increases the risk of falls and fractures. Sarcopenia serves as an independent predictor of postoperative complications, chemotherapy dose-limiting toxicity, and treatment outcomes, which affect therapy planning and perioperative management decisions. Methods to assess sarcopenia in HNC patients encompass various techniques. A sarcopenia assessment offers a potentially efficient and readily available tool for clinical practice. Interventions and management strategies for sarcopenia involve exercise interventions as a cornerstone; however, challenges arise due to patient-specific limitations during cancer treatment. A routine body composition analysis is proposed as a valuable addition to HNC patient management, with ongoing research required to refine preoperative exercise and nutrition programs for improved treatment outcomes and survival.

Impact of Psoas Muscle Area Index on Short- and Mid-Term Mortality in Patients Undergoing Valve Surgery for Infective Endocarditis: A Retrospective Analysis

Background: Sarcopenia, characterized by the loss of skeletal muscle mass, is an emerging comorbidity associated with poor outcomes in cardiovascular surgery. Its impact on mortality in patients undergoing valve surgery for infective endocarditis (IE) remains underexplored. This study investigates the relationship between sarcopenia, measured by the Psoas muscle area index (PMAi), and mortality in patients with IE undergoing valve surgery. Materials and Methods: We retrospectively analyzed 68 patients with IE who underwent valve surgery at a tertiary care center from 2013 to 2021. Sarcopenia was defined as being in the lowest quartile of PMAi, measured via preoperative computed tomography (CT). Baseline characteristics, survival outcomes, and factors influencing mortality were analyzed using Kaplan-Meier survival curves and Cox proportional hazards regression. The predictive value of PMAi for 1-year and 3-year mortality was assessed via receiver operating characteristic (ROC) curves. Results: Sarcopenia was strongly associated with increased mortality at both 1-year (HR: 0.378, p = 0.010) and 3-year follow-ups (HR: 0.457, p = 0.012). Female sex (OR: 275.748, p < 0.001) and older age (OR: 9.995, p = 0.003) were significant predictors of sarcopenia. Chronic kidney insufficiency (CKI) and the use of heart failure medication therapy also significantly impacted survival outcomes. Conclusions: Sarcopenia is a strong independent predictor of short- and mid-term mortality in patients undergoing valve surgery for IE. Routine radiological assessment of sarcopenia using PMAi could improve risk stratification and guide preoperative interventions. Tailored management strategies, especially in older women and patients with CKI, may enhance outcomes in this high-risk population.

ChatGPT-4 and wearable device assisted Intelligent Exercise Therapy for co-existing Sarcopenia and Osteoarthritis (GAISO): a feasibility study and design for a randomized controlled PROBE non-inferiority trial

BACKGROUND

Sarcopenia and osteoarthritis are prevalent age-related diseases that mutually exacerbate each other, creating a vicious cycle that worsens both conditions. Exercise is key to breaking this detrimental cycle. Facing increasing demand for rehabilitation services within this patient demographic, ChatGPT-4 and wearable device may increase the availability, efficiency and personalization of such health care.

AIM

To evaluate the clinical efficacy and cost-effectiveness of a rehabilitation system implemented on mobile platforms, utilizing the integration of ChatGPT-4 and wearable devices.

METHODS

The study design is a prospective randomized open blinded end-point (PROBE) non-inferiority trial. 278 patients diagnosed with osteoarthritis and sarcopenia will be recruited and randomly assigned to the intervention group and the control group. In the intervention group patients receive mobile phone-based rehabilitation service where ChatGPT-4 generates personalized exercise therapy, and wearable device guides and monitor the patient to implement the exercise therapy. Traditional clinic based face-to-face exercise therapy will be prescribed and implemented in the control group. All patients will receive three-months exercise therapies following the frequency, intensity, type, time, volume and progression (FITT-VP) principle. The patients will be assessed at baseline, one month, three months, and six months after initiation. Outcome measures will include ROM, gait patterns, Visual Analogue Scale (VAS) for pain assessment, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS) for functional assessment, Short-Form Health Survey 12 (SF-12) for quality of life, Minimal Clinically Important Difference (MCID), Patient Acceptable Symptom State (PASS), and Substantial Clinical Benefit (SCB) for clinically significant measures.

DISCUSSION

A rehabilitation system combining the capabilities of ChatGPT-4 and wearable devices potentially enhance the availability and efficiency of professional rehabilitation services, thus enhancing the therapeutic outcomes for a substantial population concurrently afflicted with sarcopenia and osteoarthritis.

Advancements in Drug Delivery Systems for the Treatment of Sarcopenia: An Updated Overview

Since sarcopenia is a progressive condition that leads to decreased muscle mass and function, especially in elderly people, it is a public health problem that requires attention from researchers. This review aims to highlight drug delivery systems that have a high and efficient therapeutic potential for sarcopenia. Current as well as future research needs to consider the barriers encountered in the realization of delivery systems, such as the route of administration, the interaction of the systems with the aggressive environment of the human body, the efficient delivery and loading of the systems with therapeutic agents, and the targeted delivery of therapeutic agents into the muscle tissue without creating undesirable adverse effects. Thus, this paper sets the framework of existing drug delivery possibilities for the treatment of sarcopenia, serving as an inception point for future interdisciplinary studies.

Impact of Sarcopenia on Treatment Outcomes and Toxicity in Locally Advanced Rectal Cancer

Background and Objectives: Sarcopenia, a condition characterized by muscle mass loss, is prevalent in up to 68% of rectal cancer patients and has been described as a negative prognostic factor, impacting overall survival and tumor response. While there are extensive data on rectal cancer globally, only a handful of studies have evaluated the role of sarcopenia in locally advanced rectal cancer (LARC). Our study aimed to investigate the relationship between sarcopenia, overall response rate, and toxicity in patients who underwent total neoadjuvant treatment (TNT) for LARC. Materials and Methods: We performed a retrospective study of patients with rectal cancer treated with TNT and surgery with curative intent between 2021 and 2023 at Prof. Dr. Ion Chiricuta Institute of Oncology, Cluj-Napoca. Sarcopenia was assessed on MRI images by measuring the psoas muscle area (PMA) at the level of the L4 vertebra before and after neoadjuvant therapy. The primary endpoints were the overall complete response rate (oCR) and acute toxicity. Results: This study included 50 patients with LARC. The oCR rate was 18% and was significantly associated with post-treatment sarcopenia (OR 0.08, p = 0.043). Patients who did not achieve a clinical or pathologic complete response had, on average, an 8% muscle loss during neoadjuvant therapy (p = 0.022). Cystitis and thrombocytopenia were significantly associated with post-treatment sarcopenia (p = 0.05 and p = 0.049). Conclusions: Sarcopenia and loss of psoas muscle during neoadjuvant therapy were negatively associated with tumor response in locally advanced rectal cancer. Thrombocytopenia and cystitis are more frequent in sarcopenic than non-sarcopenic patients undergoing neoadjuvant chemoradiation for rectal cancer.

No association between vascular aging and sarcopenia in healthy participants

BACKGROUND & AIMS

Several reports inform an association between vascular aging and sarcopenia. However, both conditions appear along with aging. Therefore, their association may be circumstantial and not casually linked. Our aim was to determine if individuals with higher-than-expected vascular aging have a higher frequency of sarcopenia.

METHODS

In 802 participants we calculated the association between pulse wave pressure and carotid intima media thickness and age and blood pressure, to derive predictive regression equations. In 161 of these participants we measured body composition by double beam X ray absorptiometry (DEXA), hand grip strength, rectus femoris thickness by ultrasound, activity energy expenditure by actigraphy and peak oxygen consumption and workload in an incremental exercise test. We calculated their expected values for pulse wave velocity and carotid intima media thickness and compared muscle mass and function between those with higher or lower than expected parameters. In 60 of these participants, we measured body composition sequentially to assess its change over time.

RESULTS

Age and blood pressure predicted the variance of pulse wave velocity and carotid intima media thickness with R2 values of 0.94-0.97 and 0.54 to 0.66, respectively. No differences in the frequency of sarcopenia and in muscle mass and strength were observed between participants with higher or lower than expected pulse wave velocity and carotid intima media thickness. In the group with sequential assessments, no differences in the change of muscle mass over time were observed in participants with and without accelerated vascular aging.

CONCLUSIONS

We were not able to find an association between vascular aging and sarcopenia.

Hotspots and trends in satellite cell research in muscle regeneration: A bibliometric visualization and analysis from 2010 to 2023

Background

The incidence of muscle atrophy or sports injuries is increasing with time and population aging, thereby attracting considerable attention to muscle generation research. Muscle satellite cells, which play an important role in this process, lack comprehensive literature regarding their use for muscle regeneration. Hence, this study aimed to analyze the hotspots and trends in satellite cell research from 2010 to 2023, providing a reference for muscle regeneration research.

Methods

Studies on satellite cells' role in muscle regeneration from 2010 to 2023 were retrieved from the Web of Science Core Collection. Using CiteSpace and VOSviewer, we analyzed annual publications, authors and co-citing authors, countries and institutions, journals and co-citing journals, co-citing references, and keywords.

Results

From 2010 to 2023, 1468 papers were retrieved, indicating an overall increasing trend in the number of annual publications related to satellite cells in muscle regeneration. The United States had the highest number of publications, while the Institut National de la Santé et de la Recherche Médicale was the institution with the most publications. Among journals, " PloS One" had the highest number of published papers, and "Cell" emerged as the most co-cited journal. A total of 7425 authors were involved, with Michael A. Rudnicki being the author with the highest number of publications and the most co-cited author. The most cited reference was "Satellite cells and the muscle stem cell niche." Among keywords, "satellite cells" was the most common, with "heterogeneity" having the highest centrality. Frontier themes included "Duchenne muscular dystrophy," "skeletal muscle," "in-vivo," "muscle regeneration," "mice," "muscle atrophy," "muscle fibers," "inflammation," " mesenchymal stem cells," and "satellite cell."

Conclusion

This study presents the current status and trends in satellite cell research on muscle regeneration from 2010 to 2023 using bibliometric analyses, providing valuable insights into numerous future research directions.

Effect of Bimagrumab on body composition: a systematic review and meta-analysis

BACKGROUND

Sarcopenia, a condition marked by progressive muscle mass and function decline, presents significant challenges in aging populations and those with chronic illnesses. Current standard treatments such as dietary interventions and exercise programs are often unsustainable. There is increasing interest in pharmacological interventions like bimagrumab, a monoclonal antibody that promotes muscle hypertrophy by inhibiting muscle atrophy ligands. Bimagrumab has shown effectiveness in various conditions, including sarcopenia.

AIM

The primary objective of this meta-analysis is to evaluate the impact of bimagrumab treatment on both physical performance and body composition among patients diagnosed with sarcopenia.

MATERIALS AND METHODS

This meta-analysis follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We systematically searched PubMed, Ovid/Medline, Web of Science, and the Cochrane Library databases up to June 2024 using appropriate Medical Subject Headings (MeSH) terms and keywords related to bimagrumab and sarcopenia. Eligible studies were randomized controlled trials (RCTs) that assessed the effects of bimagrumab on physical performance (e.g., muscle strength, gait speed, six-minute walk distance) and body composition (e.g., muscle volume, fat-free body mass, fat body mass) in patients with sarcopenia. Data extraction was independently performed by two reviewers using a standardized form, with discrepancies resolved through discussion or consultation with a third reviewer.

RESULTS

From an initial search yielding 46 records, we screened titles, abstracts, and full texts to include seven RCTs in our meta-analysis. Bimagrumab treatment significantly increased thigh muscle volume (mean difference [MD] 5.29%, 95% confidence interval [CI] 4.08% to 6.50%, P < 0.001; moderate heterogeneity χ2 = 6.41, I2 = 38%, P = 0.17) and fat-free body mass (MD 1.90 kg, 95% CI 1.57 kg to 2.23 kg, P < 0.001; moderate heterogeneity χ2 = 8.60, I2 = 30%, P = 0.20), while decreasing fat body mass compared to placebo (MD - 4.55 kg, 95% CI - 5.08 kg to - 4.01 kg, P < 0.001; substantial heterogeneity χ2 = 27.44, I2 = 89%, P < 0.001). However, no significant improvement was observed in muscle strength or physical performance measures such as gait speed and six-minute walk distance with bimagrumab treatment, except among participants with slower baseline walking speeds or distances.

DISCUSSION AND CONCLUSION

This meta-analysis provides valuable insights into the effects of bimagrumab on sarcopenic patients, highlighting its significant improvements in body composition parameters but limited impact on functional outcomes. The observed heterogeneity in outcomes across studies underscores the need for cautious interpretation, considering variations in study populations, treatment durations, and outcome assessments. While bimagrumab shows promise as a safe pharmacological intervention for enhancing muscle mass and reducing fat mass in sarcopenia, its minimal effects on muscle strength and broader physical performance suggest potential limitations in translating body composition improvements into functional gains. Further research is needed to clarify its long-term efficacy, optimal dosing regimens, and potential benefits for specific subgroups of sarcopenic patients.

Exploring the impact of protein intake on the association between oxidative balance score and lean mass in adults aged 20-59: NHANES 2011-2018

BACKGROUND

Previous studies have established a correlation between the pathogenesis of oxidative stress and sarcopenia. The Oxidative Balance Score (OBS) is an integrated measure that reflects the overall balance of antioxidants and pro-oxidants in dietary components and lifestyle. However, there are limited reports on the association between OBS and lean mass and the impact of protein intake on the association between OBS and lean mass.

METHODS

Using data from the National Health and Nutrition Examination Survey from 2011 to 2018, multivariate linear and logistic regression analyses were conducted to explore the associations between OBS and outcomes. The findings were then illustrated through fitted smoothing curves and threshold effect analyses.

RESULTS

This study included 2,441 participants, demonstrating that higher OBS is significantly associated with an increased ratio of appendicular lean mass to body mass index. Key inflection points at OBS 31 mark pronounced changes in these associations, with age and protein intake notably affecting the association. The effect of OBS on lean mass varies among populations with high and low protein intake.

CONCLUSIONS

Our findings suggest that OBS is significantly and positively associated with lean mass. A high protein intake of more than 84.5 g/day may enhance the role of OBS in influencing muscle health to improve muscle outcomes.

Temporalis muscle thickness as a predictor of functional outcome after reperfusion therapies for acute ischemic stroke: a retrospective, cohort study

BACKGROUND

Sarcopenia, defined as the loss of skeletal muscle mass, has been associated with a worse functional outcome after stroke. Measurement of temporal muscle thickness (TMT) has been introduced as an easily obtainable surrogate marker to identify patients with sarcopenia. Our study aims to investigate the correlation between pre-stroke sarcopenia, measured by TMT assessment, and functional outcome in patients treated with revascularization procedures for acute ischemic stroke.

METHODS

We included consecutive adult patients who underwent thrombolysis, endovascular thrombectomy or both for acute ischemic stroke at our Centre from January 2020 to June 2022. Besides collecting baseline clinical and neuroradiological features, TMT was measured on brain computed tomography scans according to a standardized protocol. Modified Rankin Scale (mRS) scores at 3 months represented the main endpoint of functional outcome.

RESULTS

A total of 261 patients were available for the analysis. In univariate models, patients with excellent outcomes (mRS = 0-1) were younger, had higher TMT values and lower pre-event disability and stroke severity. In multivariate models higher TMT values resulted independently associated with reduced mortality (Odds Ratio 0.708, 95% Confidence Interval 0.538-0.930, p = 0.013). Age, diabetes, brain bleeding events and stroke severity were found to be predictors of mortality, too.

CONCLUSIONS

Our retrospective analysis shows that in patients who underwent revascularization treatments for ischemic stroke TMT is as an independent predictor of survival easily obtainable from the baseline CT scan. Further investigation is required to confirm the role of sarcopenia assessment and TMT measurement in the prognostication toolkit of this disease.

Prevalence and Association of Sarcopenia with Mortality in Patients with Head and Neck Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

The objective of this meta-analysis was to assess the association of sarcopenia defined on computed tomography (CT) head and neck with survival in head and neck cancer patients.

METHODS

Following a PROSPERO-registered protocol, two blinded reviewers extracted data and evaluated the quality of the included studies using the Quality In Prognostic Studies (QUIPS) tool, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework. A meta-analysis was conducted using maximally adjusted hazard ratios (HRs) with the random-effects model. Heterogeneity was measured using the I2 statistic and was investigated using meta-regression and subgroup analyses where appropriate.

RESULTS

From 37 studies (11,181 participants), sarcopenia was associated with poorer overall survival (HR 2.11, 95% confidence interval [CI] 1.81-2.45; p < 0.01), disease-free survival (HR 1.76, 95% CI 1.38-2.24; p < 0.01), disease-specific survival (HR 2.65, 95% CI 1.80-3.90; p < 0.01), progression-free survival (HR 2.24, 95% CI 1.21-4.13; p < 0.01) and increased chemotherapy or radiotherapy toxicity (risk ratio 2.28, 95% CI 1.31-3.95; p < 0.01). The observed association between sarcopenia and overall survival remained significant across different locations of cancer, treatment modality, tumor stages and geographical region, and did not differ between univariate and multivariate HRs. Statistically significant correlations were observed between the C3 and L3 cross-sectional area, skeletal muscle mass, and skeletal muscle index.

CONCLUSIONS

Among patients with head and neck cancers, CT-defined sarcopenia was consistently associated with poorer survival and greater toxicity.

Multidimensional frailty assessment: Development and validation of the Tilburg Frailty Indicator-Indonesia version

The aim of this study was to develop and examine the psychometric properties of the Tilburg Frailty Indicator-Indonesian version (TFI-I). 308 community-dwelling older adults aged ≥60 years participated. The TFI-I exhibited favorable internal consistency (Cronbach's alpha = 0.775) and test-retest reliability (intraclass correlation coefficient = 0.94). The physical, psychological, and social domains of the TFI-I correlated closely with the similar constructs of other scales, including the Short Physical Performance Battery (P < .001), Fried Frailty Phenotype (P < 0.001), Geriatric Depression Scale (P < .001), and the World Health Organization Quality of Life scale (P = 0.041), indicating its favorable construct validity. Significant differences were identified between the robust and frailty groups on the Barthel Index (P = .001) and Lawton Instrumental Activity of Daily Living Scale (P < .001). Overall, the TFI-I is valid and reliable when used to evaluate frailty status in clinical and research settings.

Effects of Life-Long Exercise on Age-Related Inflammation, Apoptosis, Oxidative Stress, Ferroptosis Markers, and NRF2/KAEP 1/Klotho Pathway in Rat Kidneys

Xi-Kun Yuan Pin-Shi Ni Zhen-Hao Yan Zhi Yu Zhuang-Zhi Wang Chen-Kai Zhang Fang-Hui Li Xiao-Ming Yu 1Sports Department, Nanjing University of Science and Technology ZiJin College, Nanjing, China, 2School of Sport Sciences, Nanjing Normal University, Nanjing, China, 3Shanghai Seventh People's Hospital, Shanghai, China To investigate the effects of life-long exercise (LLE) on age-related inflammatory cytokines, apoptosis, oxidative stress, ferroptosis markers, and the NRF2/KAEP 1/Klotho pathway in rats. Eight-month-old female Sprague-Dawley rats were divided into four groups: 1) LLE: 18-month LLE training starting at 8 months of age, 2) Old moderate-intensity continuous training (OMICT): 8 months of moderate-intensity continuous training starting at 18 months of age, 3) Adult sedentary (ASED): 8 month-old adult sedentary control group, and 4) Old sedentary (OSED): a 26-month-old sedentary control group. Hematoxylin eosin staining was performed to observe the pathological changes of kidney tissue injury in rats; Masson's staining to observe the deposition of collagen fibers in rat kidney tissues; and western blotting to detect the expression levels of IL-6, IL 1beta, p53, p21, TNF-alpha, GPX4, KAEP 1, NRF2, SLC7A11, and other proteins in kidney tissues. Results: Compared with the ASED group, the OSED group showed significant morphological changes in renal tubules and glomeruli, which were swollen and deformed, with a small number of inflammatory cells infiltrated in the tubules. Compared with the OSED group, the expression levels of inflammation-related proteins such as IL-1beta, IL-6, TNF alpha, and MMP3 were significantly lower in the LLE group. Quantitative immunofluorescence analysis and western blotting revealed that compared with the ASED group, KAEP 1 protein fluorescence intensity and protein expression levels were significantly enhanced, while Klotho and NRF2 protein fluorescence intensity and protein expression levels were reduced in the OSED group. Compared with the OSED group, KAEP 1 protein fluorescence intensity and protein expression levels were reduced in the LLE and OMICT groups. Klotho and KAEP 1 protein expression levels and immunofluorescence intensity were higher in the LLE group than in the OSED group. The expression levels of GPX4 and SLC7A11, two negative marker proteins associated with ferroptosis, were significantly higher in the LLE group than in the OSED group, while the expression of p53 a cellular senescence-associated protein that negatively regulates SLC7A11, and the downstream protein p21 were significantly decreased. LLE may ameliorated aging-induced oxidative stress, inflammatory response, apoptosis, and ferroptosis by regulating Klotho and synergistically activating the NRF2/KAEP 1 pathway. Keywords: Life-long exercise, Moderate intensity continuous training, Aging, Kidney tissue, Ferroptosis.

The association between non‑high‑density lipoprotein cholesterol to high‑density lipoprotein cholesterol ratio (NHHR) and low muscle mass in adults aged 20-59: a population-based study in the United States

BACKGROUND

The ratio between non-high-density lipoprotein cholesterol and high-density lipoprotein cholesterol (NHHR) is a reliable marker for assessing the risk linked to lipid metabolism disorders. Sarcopenia, characterized by age-related loss of muscle mass and strength/function, includes the assessment of muscle mass, muscle strength, and muscle-specific strength. However, research into NHHR's relationship with low muscle mass risk remains unexplored.

METHODS

Our study utilized a cross-sectional approach, examining data derived from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018. Through multivariable linear and logistic regression, we investigated the relationships of the NHHR with muscle mass and low muscle mass. We visualized the results using smoothing curves and assessed threshold effects. We also performed various subgroup and sensitivity analyses.

RESULTS

This research encompassed 9,012 participants and demonstrated significant nonlinear associations between NHHR and ALMBMI or low muscle mass risk in a generalized additive model (GAM), pinpointing critical NHHR values (3.328 and 3.367) where changes in NHHR significantly impacted ALMBMI and low muscle mass risk.

CONCLUSIONS

The NHHR demonstrates a significant association with an increased risk of low muscle mass among middle-aged Americans. This ratio has potential as a predictive marker for low muscle mass. Further exploration of NHHR is expected to aid in advancing preventive and therapeutic measures for this condition.

Impact of the COVID-19 pandemic on risk of sarcopenia: From lockdown and infection perspectives: A systematic review and meta-analysis

BACKGROUND

During the new coronavirus disease 2019 (COVID-19) pandemic, there are numerous symptoms in the skeletal muscular system, such as decreased skeletal muscle mass, strength, and muscle function, which are the main manifestations of sarcopenia. To investigate the impact of the COVID-19 pandemic on sarcopenia from the perspectives of COVID-19 pandemic lockdown and COVID-19 infection, we conducted this study.

METHODS

We searched for literature related to COVID-19 and sarcopenia published in PubMed, Embase, Cochrane Library, and Web of Science. Two researchers independently searched and screened the articles, extracted data, and assessed the quality of the final included literature. RevMan 5.4 was used for meta-analysis.

RESULTS

A total of 8 articles with a total of 1145 patients were included. There was a significant difference in SARC-F scores (MD = 0.67, 95%CI = [0.41, 0.93], Z = 5.00, P < .00001), handgrip (MD = -1.57, 95%CI = [-2.41, -0.73], Z = 3.66, P = .0002), body weight (MD = -1.87, 95%CI = [-3.69, -0.05], Z = 2.01, P = .04), and skeletal muscle mass index (MD = -0.28, 95%CI = [-0.54, -0.02], Z = 2.13, P = .03) between the time before the COVID-19 pandemic and during the COVID-19 pandemic. However, the results showed that there was no significant difference in muscle mass between the 2 groups (MD = -1.72, 95%CI = [-4.39, 0.94], Z = 1.27, P = .21).

CONCLUSION

The COVID-19 pandemic has had an impact on sarcopenia. Both infection with COVID-19 and lockdown during the COVID-19 pandemic increase the risk of sarcopenia. Research should pay more attention to this disease during the COVID-19 pandemic and adopt effective interventions to minimize adverse outcomes.

Frailty after Liver Transplantation: A Complex Unexplored Issue

Frailty is a multidimensional syndrome predominantly studied in the elderly, characterized by reduced resistance to stressors due to diminished physiological reserve and resilience. Advances in surgical techniques and immunosuppressive drugs have improved long-term survival rates in solid organ transplant recipients, yet the 10-year survival is satisfying. However, liver transplant recipients have a noteworthy risk of developing frailty status. After liver transplant, frailty can be favored by socioeconomic, cultural, and health-related factors, leading to increased risks of hospitalization, morbidity, and mortality. Various tools for frailty assessment exist, but none are universally validated for post-transplant patients. The integration of socioeconomic and psychological factors into frailty evaluation could improve quality of life and long-term outcomes for transplant recipients. Multidisciplinary approaches, including psychosocial support, are essential for managing frailty and enhancing the overall care of transplanted patients. This narrative review aims to comprehensively address the principal frailty risk factors associated with liver transplantation.

Prognostic impact of shift to low visceral fat mass after neoadjuvant chemotherapy in patients with esophageal cancer

BACKGROUND

Based on the JCOG1109 trial, it is suggested that the combination of docetaxel, cisplatin, and 5-fluorouracil (DCF) could potentially become a standard neoadjuvant chemotherapy regimen, alongside the conventional 5-fluorouracil and cisplatin (CF) therapy, for esophageal cancer. However, there are few reports on the impact of body composition changes associated with neoadjuvant chemotherapy on prognosis.

AIM

Our study aimed to explore the effect of different neoadjuvant chemotherapy regimens on body composition during treatment and the impacts of body composition changes on their prognosis.

METHODS AND RESULTS

This is a retrospective study of 215 patients with advanced thoracic esophageal cancer who had surgery after neoadjuvant chemotherapy from 2013 to 2019. Computed tomography scans were performed before and after neoadjuvant chemotherapy to assess body composition. Skeletal muscle mass index (SMI) was calculated by dividing total skeletal muscle mass at the 3rd lumbar level by the square of height, while visceral and subcutaneous fat masses were measured at the level of umbilicus. Patients in the lowest 25% of both sexes were classified into the low visceral fat and low subcutaneous fat groups, respectively. Of the patients enrolled, 178 were male and 37 were female. Among them, 91 had clinical Stage II disease, and 124 had clinical Stage III disease. Additionally, 146 patients received neoadjuvant chemotherapy CF, and 69 received neoadjuvant chemotherapy DCF. Comparing the DCF and CF groups, the DCF group consisted of significantly younger patients (p < .01), a higher proportion of males (p = .03), and a greater number of clinical Stage III cases (p < .01). However, although percent change in SMI and visceral fat mass was not significantly different between two regimens, percent change in subcutaneous fat mass was significant in the DCF group. The major prognostic factors for patients undergoing surgery after neoadjuvant chemotherapy for thoracic esophageal cancer were clinical Stage III, transition to low visceral fat, and response rating (SD/PD), while the specific neoadjuvant chemotherapy regimen did not significantly influence the outcomes.

CONCLUSION

This study suggests that prevention of the shift to low visceral fat throughout the neoadjuvant chemotherapy process should improve patient outcomes.

Muscle Mass Adjusted by Body Height is not Correlated with Mobility of Middle-Aged and Older Adults

Background

Low muscle mass and obesity are associated with mobility disability, cardiometabolic diseases, and loss of independence. Three skeletal muscle indices (SMIs) are proposed to adjust the body size of individuals. However, it is unknown which index is better correlated with mobility. Additionally, it remains unclear whether low muscle mass or abdominal obesity has a greater impact on the mobility and cardiometabolic health of older adults.

Objectives

This study explored the association between different SMIs {appendicular skeletal muscle mass [ASM] adjusted by body height [Ht], body weight [Wt], or body mass index [BMI (kg/m2)]} and mobility/cardiometabolic health. The roles of low muscle mass and abdominal obesity in the mobility and cardiometabolic health of individuals were also identified.

Methods

Four-hundred and twenty-seven community-dwelling middle-aged and older adults underwent body composition assessments [dual-energy x-ray absorptiometry and waist circumference (WC)], grip strength, and mobility (timed up-and-go test and chair stand test). Spearman's rank correlation coefficient and regression models were used to examine research questions. This study was registered in the Thai Clinical Trials Registry (registration number: TCTR20210521007).

Results

All SMIs were positively correlated with the grip strength (ASM/Ht2: r = 0.392; ASM/Wt: r = 0.439; ASM/BMI: r = 0.569). Regarding mobility, only ASM/Ht2 wasn't relevant. After adjusting for age, sex, and WC, ASM/BMI was the only SMI associated with grip strength (β = 0.274). When age and sex were controlled, WC, but not SMI, was associated with mobility and cardiometabolic health.

Conclusions

ASM/Ht2 did not correlate with mobility in middle-aged and older adults, whereas ASM/Wt and ASM/BMI did. Abdominal obesity has a greater impact on mobility and cardiometabolic health than low muscle mass in middle-aged and older adults. We recommend using ASM/BMI to identify the low muscle mass of individuals. In addition, clinicians should note the important role of abdominal obesity when considering mobility in middle-aged and older adults.

Clinical Significance of Sarcopenia in Elderly Patients Undergoing Endoscopic Submucosal Dissection: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

As global life expectancy rises and gastrointestinal tumor incidence increases, more elderly patients are undergoing endoscopic submucosal dissection (ESD) for tumor treatment. The current situation highlights the importance of sarcopenia assessment before ESD. This systematic review and meta-analysis aim to assess sarcopenia's role in predicting post-ESD adverse outcomes in the elderly.

METHODS

We conducted a systematic review and meta-analysis to investigate the impact of sarcopenia on the prognosis of elderly patients undergoing ESD treatment. A comprehensive search was conducted across three databases (PubMed, Embase, Web of Science). We were using NEWCASTLE-OTTAWA ASSESSMENT SCALE for risk of bias assessment. The data were synthesized using Review Manager 5.3.

RESULTS

A total of 9 reports were identified, analyzing 7 indicators, with a combined sample size of 6044. Through a series of analyses, we have derived several highly credible research findings: the overall OR and 95% CI for gastric and colorectal post-ESD perforation between sarcopenia and nonsarcopenia groups were 1.34 [0.92, 1.97], for CTCAE grade > 2 was 2.65 [1.45, 4.82], for upper gastrointestinal post-ESD pneumonia were 1.97 [1.30, 2.99], and for gastric post-ESD mortality within 5 years were 2.96 [1.33, 6.58].

CONCLUSIONS

Sarcopenia is a risk factor for increased incidence of complications (CTCAE > 2) after undergoing gastric and colorectal ESD, increased pneumonia rates, and higher mortality rates within five years following gastric ESD treatment in elderly patients. However, sarcopenia does not lead to an increased perforation rate in elderly patients undergoing gastric and colorectal ESD treatments. Registration and protocol: The protocol for this study was registered on the Open Science Framework in 2024 https://doi.org/10.17605/OSF.IO/7B2CZ . We also conducted pre-registration on PROSPERO (CRD42024532547).

Diabetic Sarcopenia. A proposed muscle screening protocol in people with diabetes : Expert document

OBJECTIVES

To propose the grounds for "diabetic sarcopenia" as a new comorbidity of diabetes, and to establish a muscle screening algorithm proposal to facilitate its diagnosis and staging in clinical practice.

METHOD

A qualitative expert opinion study was carried out using the nominal technique. A literature search was performed with the terms "screening" or "diagnostic criteria" and "muscle loss" or "sarcopenia" and "diabetes" that was sent to a multidisciplinary group of 7 experts who, in a face-to-face meeting, discussed various aspects of the screening algorithm.

RESULTS

The hallmark of diabetic sarcopenia (DS) is muscle mass atrophy characteristic of people with diabetes mellitus (DM) in contrast to the histological and physiological normality of muscle mass. The target population to be screened was defined as patients with DM with a SARC-F questionnaire > 4, glycosylated haemoglobin (HbA1C) ≥ 8.0%, more than 5 years since onset of DM, taking sulfonylureas, glinides and sodium/glucose cotransporter inhibitors (SGLT2), as well as presence of chronic complications of diabetes or clinical suspicion of sarcopenia. Diagnosis was based on the presence of criteria of low muscle strength (probable sarcopenia) and low muscle mass (confirmed sarcopenia) using methods available in any clinical consultation room, such as dynamometry, the chair stand test, and Body Mass Index (BMI)-adjusted calf circumference. DS was classified into 4 stages: Stage I corresponds to sarcopenic patients with no other diabetes complication, and Stage II corresponds to patients with some type of involvement. Within Stage II are three sublevels (a, b and c). Stage IIa refers to individuals with sarcopenic diabetes and some diabetes-specific impairment, IIb to sarcopenia with functional impairment, and IIc to sarcopenia with diabetes complications and changes in function measured using standard tests Conclusion: Diabetic sarcopenia has a significant impact on function and quality of life in people with type 2 diabetes mellitus (T2DM), and it is important to give it the same attention as all other traditionally described complications of T2DM. This document aims to establish the foundation for protocolising the screening and diagnosis of diabetic sarcopenia in a manner that is simple and accessible for all levels of healthcare.

Fermented Yak-Kong using Bifidobacterium animalis derived from Korean infant intestine effectively relieves muscle atrophy in an aging mouse model

Yak-Kong (YK) is a small black soybean widely cultivated in Korea. It is considered to have excellent health functionality, as it has been reported to have better antioxidant efficacy than conventional black or yellow soybeans. Since YK has been described as good for the muscle health of the elderly in old oriental medicine books, this study sought to investigate the effect of fermented YK with Bifidobacterium animalis subsp. lactis LDTM 8102 (FYK) on muscle atrophy. In C2C12 mouse myoblasts, FYK elevated the expression of MyoD, total MHC, phosphorylated AKT, and PGC1α. In addition, two kinds of in vivo studies were conducted using both an induced and normal aging mouse model. The behavioral test results showed that in the induced aging mouse model, FYK intake alleviated age-related muscle weakness and loss of exercise performance. In addition, FYK alleviated muscle mass decrease and improved the expression of biomarkers including total MHC, myf6, phosphorylated AKT, PGC1α, and Tfam, which are related to myoblast differentiation, muscle protein synthesis, and mitochondrial generation in the muscle. In the normal aging model, FYK consumption did not increase muscle mass, but did upregulate the expression levels of biomarkers related to myoblast differentiation, muscle hypertrophy, and muscle function. Furthermore, it mitigated age-related declines in skeletal muscle force production and functional limitation by enhancing exercise performance and grip strength. Taken together, the results suggest that FYK has the potential to be a new functional food material that can alleviate the loss of muscle mass and strength caused by aging and prevent sarcopenia.

Implant-related and medical complications in patients with sarcopenia undergoing total shoulder arthroplasty: A retrospective matched-cohort analysis

Background

In the continually aging United States population, the number of patients with sarcopenia who undergo shoulder arthroplasty may concomitantly increase. This retrospective cohort study aims to evaluate the rates of short-term implant-related and medical complications following shoulder arthroplasty in patients with and without a recent diagnosis of sarcopenia.

Methods

An exact 1:3 matched analysis of 4177 patients was performed using the PearlDiver database. Multivariable logistic regression was used to compare complications, Kaplan-Meier failure analysis was used to compare the cumulative hospital readmission rates. Two-sample T-testing was used to compare the 90-day cost of care.

Results

Sarcopenic patients were significantly more likely to experience postoperative shoulder instability (odds ratio (OR) = 2.32, 95% confidence interval (CI), 1.21-4.39) and periprosthetic infection (OR = 3.83, 95% CI, 1.74-8.67) within 1 year of their arthroplasty. Sarcopenic patients were at 25% and 41% greater risk of emergency department presentation and hospital readmission 1-year post-arthroplasty, respectively. Ninty-day total costs were greater among sarcopenics ($16 112.23 vs. 10 679.58, p < 0.001).

Conclusion

These results are important for orthopaedic surgeons counselling patients with a low muscle mass on the potential for increased complications after undergoing a total shoulder arthroplasty procedure.

Urban-rural differences in the prevalence and associated factors of sarcopenia: A systematic review and meta-analysis

BACKGROUND

Loss of muscle mass, muscle strength, and/or physical performance due to aging is known as sarcopenia. Regardless of how serious this illness is, no single diagnostic criteria have been established. Much research conducted recently has demonstrated differences between built environment characteristics (i.e., urban and rural) and the occurrence of sarcopenia; however, variations in sarcopenia prevalence in urban-rural areas around the world have been reported by fewer studies. This work sought to determine how sarcopenia prevalence varied between urban and rural areas and to explore the associated influencing factors.

METHODS

Using the pertinent MESH phrases and free words, PubMed, Web of Science, Embase, and China national knowledge infrastructure databases were scanned for core sarcopenia literature up to February 26, 2023. Observational studies involving urban-rural patients with sarcopenia published in Chinese and English, and assessing muscle mass via computed tomography, bioelectrical impedance, or dual-energy X-ray absorption techniques were considered as inclusion criteria. The meta-analysis involved analysis of the urban-rural prevalence in subgroups by diagnostic criteria, tools for assessing muscle mass and study type, as well as the factors related to urban-rural differences in the occurrence of sarcopenia. STATA version 11.0 was used to perform the statistical analysis.

RESULTS

Sixty-six articles involving 433,091 participants were included for analysis: of which 27 were analyzed for both prevalence and related factors whereas 39 were for only prevalence. The meta-analysis revealed the prevalence of sarcopenia to be 0.18 (95 % CI 0.14-0.22), with significant heterogeneity (P < 0.001; I2 = 99.9 %). Moreover, the prevalence of sarcopenia in urban group [0.16 (I2 = 99.9 %, 95 % CI 0.1-0.22)] was lower than in rural group [0.2 (I2 = 99.6 %, 95 % CI 0.16-0.25)] and urban-rural group [0.21 (I2 = 97.5 %, 95 % CI 0.16-0.25)]. Besides, the factors significantly associated with sarcopenia in urban-rural areas were age, gender, BMI, malnutrition, physical activity, and polypharmacy. There was significant heterogeneity between these factors and the association of sarcopenia.

CONCLUSIONS

Sarcopenia is associated with aspects of the built environment, and studies have revealed that sarcopenia is more common in rural than in urban populations with influencing factors including age, gender, BMI, poor nutrition, insufficient physical activity, and polypharmacy. The lack of uniform diagnostic criteria makes a robust and comprehensive assessment difficult. Therefore, the formation of certain universal and standardized diagnostic criteria will help future research on sarcopenia.

Bioinformatics and system biology approach to identify potential common pathogenesis for COVID-19 infection and sarcopenia

Sarcopenia is a condition characterized by age-related loss of muscle mass and strength. Increasing evidence suggests that patients with sarcopenia have higher rates of coronavirus 2019 (COVID-19) infection and poorer post-infection outcomes. However, the exact mechanism and connections between the two is unknown. In this study, we used high-throughput data from the GEO database for sarcopenia (GSE111016) and COVID-19 (GSE171110) to identify common differentially expressed genes (DEGs). We conducted GO and KEGG pathway analyses, as well as PPI network analysis on these DEGs. Using seven algorithms from the Cytoscape plug-in cytoHubba, we identified 15 common hub genes. Further analyses included enrichment, PPI interaction, TF-gene and miRNA-gene regulatory networks, gene-disease associations, and drug prediction. Additionally, we evaluated immune cell infiltration with CIBERSORT and assessed the diagnostic accuracy of hub genes for sarcopenia and COVID-19 using ROC curves. In total, we identified 66 DEGs (34 up-regulated and 32 down-regulated) and 15 hub genes associated with sarcopenia and COVID-19. GO and KEGG analyses revealed functions and pathways between the two diseases. TF-genes and TF-miRNA regulatory network suggest that FOXOC1 and hsa-mir-155-5p may be identified as key regulators, while gene-disease analysis showed strong correlations with hub genes in schizophrenia and bipolar disorder. Immune infiltration showed a correlation between the degree of immune infiltration and the level of infiltration of different immune cell subpopulations of hub genes in different datasets. The ROC curves for ALDH1L2 and KLF5 genes demonstrated their potential as diagnostic markers for both sarcopenia and COVID-19. This study suggests that sarcopenia and COVID-19 may share pathogenic pathways, and these pathways and hub genes offer new targets and strategies for early diagnosis, effective treatment, and tailored therapies for sarcopenia patients with COVID-19.

Mouse sarcopenia model reveals sex- and age-specific differences in phenotypic and molecular characteristics

Our study was to characterize sarcopenia in C57BL/6J mice using a clinically relevant definition to investigate the underlying molecular mechanisms. Aged male (23-32 months old) and female (27-28 months old) C57BL/6J mice were classified as non-, probable-, or sarcopenic based on assessments of grip strength, muscle mass, and treadmill running time, using 2 SDs below the mean of their young counterparts as cutoff points. A 9%-22% prevalence of sarcopenia was identified in 23-26 month-old male mice, with more severe age-related declines in muscle function than mass. Females aged 27-28 months showed fewer sarcopenic but more probable cases compared with the males. As sarcopenia progressed, a decrease in muscle contractility and a trend toward lower type IIB fiber size were observed in males. Mitochondrial biogenesis, oxidative capacity, and AMPK-autophagy signaling decreased as sarcopenia progressed in males, with pathways linked to mitochondrial metabolism positively correlated with muscle mass. No age- or sarcopenia-related changes were observed in mitochondrial biogenesis, OXPHOS complexes, AMPK signaling, mitophagy, or atrogenes in females. Our results highlight the different trajectories of age-related declines in muscle mass and function, providing insights into sex-dependent molecular changes associated with sarcopenia progression, which may inform the future development of novel therapeutic interventions.

Association of the oxidative balance score with sarcopenia among young and middle-aged adults: findings from NHANES 2011-2018

Background

Sarcopenia is associated with oxidative stress. The Oxidative Balance Score (OBS) is commonly used to assess dietary and lifestyle exposure to oxidative stress. However, few studies in the literature have assessed the correlation between sarcopenia and OBS.

Aim

This study aimed to assess the association between OBS and sarcopenia among young and middle-aged adults in the United States using data from the National Health and Nutrition Examination Survey (NHANES).

Method

Weighted logistic regression analysis was used to investigate the association between OBS and sarcopenia based on data from NHANES 2011-2018. Subgroup analyses were performed to observe the consistency of the outcomes, and the stability of the results was tested using sensitivity analyses.

Result

The final sample included 5,525 young and middle-aged American adults. A higher OBS was associated with a lower risk of sarcopenia. In the fully adjusted model, the second (odds ratio [OR]: 0.62, 95% confidence interval [CI]: 0.41, 0.94; p = 0.023), third (OR: 0.50; 95% CI: 0.34, 0.74; p < 0.001), and highest quartiles (OR: 0.18; 95% CI: 0.11, 0.28; p < 0.001) of the OBS were associated with higher risks of sarcopenia when compared to the lowest quartile. This association was consistent across both dietary and lifestyle OBS scores. Our subgroup analysis revealed no significant differences between the subgroups of variables included in the interaction analysis. Sensitivity analyses revealed similar results.

Conclusion

Our study showed that higher antioxidant and lower antioxidant exposure may decrease the risk of developing sarcopenia. Higher OBS scores may indicate greater protection against sarcopenia; however, further clinical studies are warranted to confirm these findings.

Identification of shared gene signatures and pathways for diagnosing osteoporosis with sarcopenia through integrated bioinformatics analysis and machine learning

BACKGROUND

Prior studies have suggested a potential relationship between osteoporosis and sarcopenia, both of which can present symptoms of compromised mobility. Additionally, fractures among the elderly are often considered a common outcome of both conditions. There is a strong correlation between fractures in the elderly population, decreased muscle mass, weakened muscle strength, heightened risk of falls, and diminished bone density. This study aimed to pinpoint crucial diagnostic candidate genes for osteoporosis patients with concomitant sarcopenia.

METHODS

Two osteoporosis datasets and one sarcopenia dataset were obtained from the Gene Expression Omnibus (GEO). Differential expression genes (DEGs) and module genes were identified using Limma and Weighted Gene Co-expression Network Analysis (WGCNA), followed by functional enrichment analysis, construction of protein-protein interaction (PPI) networks, and application of a machine learning algorithm (least absolute shrinkage and selection operator (LASSO) regression) to determine candidate hub genes for diagnosing osteoporosis combined with sarcopenia. Receiver operating characteristic (ROC) curves and column line plots were generated.

RESULTS

The merged osteoporosis dataset comprised 2067 DEGs, with 424 module genes filtered in sarcopenia. The intersection of DEGs between osteoporosis and sarcopenia module genes consisted of 60 genes, primarily enriched in viral infection. Through construction of the PPI network, 30 node genes were filtered, and after machine learning, 7 candidate hub genes were selected for column line plot construction and diagnostic value assessment. Both the column line plots and all 7 candidate hub genes exhibited high diagnostic value (area under the curve ranging from 1.00 to 0.93).

CONCLUSION

We identified 7 candidate hub genes (PDP1, ALS2CL, VLDLR, PLEKHA6, PPP1CB, MOSPD2, METTL9) and constructed column line plots for osteoporosis combined with sarcopenia. This study provides reference for potential peripheral blood diagnostic candidate genes for sarcopenia in osteoporosis patients.

Frontiers in sarcopenia: Advancements in diagnostics, molecular mechanisms, and therapeutic strategies

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia's pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway's role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

Predictive role of preoperative sarcopenia for long-term survival in rectal cancer patients: A meta-analysis

PURPOSE

To identify the predictive role of sarcopenia in long-term survival among rectal cancer patients who underwent surgery based on available evidence.

METHODS

The Medline, EMBASE and Web of Science databases were searched up to October 20, 2023, for relevant studies. Overall survival (OS), disease-free survival (DFS) and cancer-specific survival (CSS) were the endpoints. Hazard ratios (HRs) and 95% confidence intervals (CIs) were combined to evaluate the association between sarcopenia and survival.

RESULTS

Fifteen studies with 4283 patients were included. The pooled results demonstrated that preoperative sarcopenia significantly predicted poorer OS (HR = 2.07, 95% CI = 1.67-2.57, P<0.001), DFS (HR = 1.85, 95% CI = 1.39-2.48, P<0.001) and CSS (HR = 1.83, 95% CI = 1.31-2.56, P<0.001). Furthermore, subgroup analysis based on neoadjuvant therapy indicated that sarcopenia was a risk factor for worse OS and DFS in patients who received (OS: HR = 2.44, P<0.001; DFS: HR = 2.16, P<0.001) but not in those who did not receive (OS: HR = 2.44, P<0.001; DDFS: HR = 1.86, P = 0.002) neoadjuvant chemoradiotherapy. In addition, subgroup analysis based on sample size and ethnicity showed similar results.

CONCLUSION

Preoperative sarcopenia is significantly related to poor survival in surgical rectal cancer patients and could serve as a novel and valuable predictor of long-term prognosis in these patients.

Associations of CBC-Derived inflammatory indicators with sarcopenia and mortality in adults: evidence from Nhanes 1999 ∼ 2006

BACKGROUND

It has been proposed that inflammation plays a role in the development of sarcopenia. This study aimed to investigate the links of complete blood cell count (CBC) parameters and CBC-derived inflammatory indicators with sarcopenia and mortality.

METHODS

Data pertaining to sarcopenia were extracted from the 1999-2006 National Health and Nutrition Examination Survey (NHANES), and mortality events were ascertained through the National Death Index up to December 31, 2019. The CBC-derived inflammatory indicators assessed in this study included the neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), monocyte-to-lymphocyte ratio (MLR), neutrophil-monocyte to lymphocyte ratio (NMLR), systemic inflammatory response index (SIRI), and systemic immune-inflammation index (SII). The prognostic significance of these CBC-derived inflammatory indicators was evaluated using the random survival forests (RSF) analysis.

RESULTS

The study encompassed a cohort of 12,689 individuals, among whom 1,725 were diagnosed with sarcopenia. Among individuals with sarcopenia, 782 experienced all-cause mortality, and 195 succumbed to cardiovascular causes. Following adjustment for confounding variables, it was observed that elevated levels of NLR, dNLR, NMLR, SIRI, and SII were associated with an increased prevalence of sarcopenia. Among participants with sarcopenia, those in the highest quartile of NLR (HR = 1.336 [1.095-1.631]), dNLR (HR = 1.274 [1.046-1.550]), MLR (HR = 1.619 [1.290-2.032]), NMLR (HR = 1.390 [1.132-1.707]), and SIRI (HR = 1.501 [1.210-1.862]) exhibited an elevated risk of all-cause mortality compared to those in the lowest quartile of these inflammation-derived indicators. These associations were similarly observed in cardiovascular mortality (HR = 1.874 [1.169-3.003] for MLR, HR = 1.838 [1.175-2.878] for SIRI). The RSF analysis indicated that MLR exhibited the highest predictive power for both all-cause and cardiovascular mortality among individuals with sarcopenia.

CONCLUSIONS

Our findings underscore the association between CBC-derived inflammatory indicators and mortality in adults with sarcopenia. Of note, MLR emerged as the most robust predictor of all-cause and cardiovascular mortality in this population.

Low Daily Step Count Associated with Small Erector Spinae Muscle Area and Sarcopenia in Idiopathic Pulmonary Fibrosis

Objective The daily step count is associated with mortality in idiopathic pulmonary fibrosis (IPF). However, the factors associated with this phenomenon are not yet fully understood. We therefore clarified its association with clinical parameters. Methods Fifty-nine patients with IPF with available data for daily step counts; 6-minute walk distance (6MWD); chest, abdominal, and pelvic computed tomography (CT); pulmonary function; psychological evaluations; and sarcopenia assessments were prospectively enrolled. The daily step count was measured continuously for seven consecutive days. The cross-sectional areas of the erector spinae muscles at the level of the 12th vertebra (ESMCSA) and psoas major muscle volume (PMV) obtained by CT were assessed. Results The average age of the patients was 73.3±8.1 years old, and the percent predicted forced vital capacity was 81.6%±15.8%. The median daily step count was 4,258 (2,155-6,991) steps. The average 6MWD, ESMCSA, and PMV were 413±97 m, 25.5±6.7 cm2, and 270±75.6 cm3, respectively. A linear regression analysis for daily step count showed that the ESMCSA and 6MWD were independent factors for the daily step count, whereas the PMV and skeletal muscle index were not. The daily step count, ESMCSA, and 6MWD were lower in patients with sarcopenia than in those without sarcopenia. Conclusion A lower daily step count was associated with a smaller erector spinae muscle area and sarcopenia in patients with IPF. Further studies are warranted to confirm the importance of physical therapy for muscle strengthening in patients with IPF.

Non-Pharmacological Strategies for Managing Sarcopenia in Chronic Diseases

This article focuses on a range of non-pharmacological strategies for managing sarcopenia in chronic diseases, including exercise, dietary supplements, traditional Chinese exercise, intestinal microecology, and rehabilitation therapies for individuals with limited limb movement. By analyzing multiple studies, the article aims to summarize the available evidence to manage sarcopenia in individuals with chronic diseases. The results strongly emphasize the role of resistance training in addressing chronic diseases and secondary sarcopenia. Maintaining the appropriate frequency and intensity of resistance training can help prevent muscle atrophy and effectively reduce inflammation. Although aerobic exercise has limited ability to improve skeletal muscle mass, it does have some positive effects on physical function. Building upon this, the article explores the potential benefits of combined training approaches, highlighting their helpfulness for overall quality of life. Additionally, the article also highlights the importance of dietary supplements in combating muscle atrophy in chronic diseases. It focuses on the importance of protein intake, supplements rich in essential amino acids and omega-3, as well as sufficient vitamin D to prevent muscle atrophy. Combining exercise with dietary supplements appears to be an effective strategy for preventing sarcopenia, although the optimal dosage and type of supplement remain unclear. Furthermore, the article explores the potential benefits of intestinal microecology in sarcopenia. Probiotics, prebiotics, and bacterial products are suggested as new treatment options for sarcopenia. Additionally, emerging therapies such as whole body vibration training, blood flow restriction, and electrical stimulation show promise in treating sarcopenia with limited limb movement. Overall, this article provides valuable insights into non-pharmacological strategies for managing sarcopenia in individuals with chronic diseases. It emphasizes the importance of a holistic and integrated approach that incorporates exercise, nutrition, and multidisciplinary interventions, which have the potential to promote health in the elderly population. Future research should prioritize high-quality randomized controlled trials and utilize wearable devices, smartphone applications, and other advanced surveillance methods to investigate the most effective intervention strategies for sarcopenia associated with different chronic diseases.

Network meta-analysis of the intervention effects of different exercise measures on Sarcopenia in cancer patients

PURPOSE

This study aims to investigate the impact of four exercise modes (aerobic exercise, resistance exercise, aerobic combined with resistance multimodal exercise, and stretching) on the physical performance of cancer patients.

METHODS

Randomized controlled trials (RCTs) were exclusively collected from PubMed, EMBASE, Web of Science, and The Cochrane Library, with a search deadline of April 30, 2023. Different exercise interventions on the physical performance of cancer patients were studied, and the Cochrane risk of bias assessment tool was employed to evaluate the quality of the included literature. Data analysis was conducted using STATA 15.1 software.

RESULTS

This study included ten randomized controlled trials with a combined sample size of 503 participants. Network meta-analysis results revealed that aerobic combined with resistance multimodal exercise could reduce fat mass in cancer patients (SUCRA: 92.3%). Resistance exercise could improve lean mass in cancer patients (SUCRA: 95.7%). Furthermore, resistance exercise could enhance leg extension functionality in cancer patients with sarcopenia (SUCRA: 83.0%).

CONCLUSION

This study suggests that resistance exercise may be more beneficial for cancer-related sarcopenia.In clinical practice, exercise interventions should be tailored to the individual patients' circumstances.

REGISTRATION NUMBER

This review was registered on INPLASY2023110025; DOI number is https://doi.org/10.37766/inplasy2023.11.0025 .

Sarcopenia in gynaecological cancers

Gynaecological cancers (GCs) comprise a group of cancers that originate in the female reproductive organs. Each GC is unique, with different signs and symptoms, risk factors and therapeutic strategies. Worldwide, the majority of GCs are still associated with high mortality rates, especially ovarian, due to difficulty in early detection. Despite numerous studies on the underlying pathophysiology, research in the field of GCs poses unique scientific and technological challenges. These challenges require a concerted multi- and inter-disciplinary effort by the clinical, scientific and research communities to accelerate the advancement of prognostic, diagnostic, and therapeutic approaches. Sarcopenia is a multifactorial disease which leads to the systemic loss of skeletal muscle mass and function. It can be caused by malignancies, as well as due to malnutrition, physical inactivity, ageing and neuromuscular, inflammatory, and/or endocrine diseases. Anorexia and systemic inflammation can shift the metabolic balance of patients with cancer cachexia towards catabolism of skeletal muscle, and hence sarcopenia. Therefore, sarcopenia is considered as an indicator of poor general health status, as well as the possible indicator of advanced cancer. There is a growing body of evidence showing the prognostic significance of sarcopenia in various cancers, including GCs. This review will outline the clinical importance of sarcopenia in patients with GCs.

Investigating the effects of synbiotic supplementation on functional movement, strength and muscle health in older Australians: a study protocol for a double-blind, randomized, placebo-controlled trial

BACKGROUND

Aging has been associated with a progressive loss of skeletal muscle quality, quantity and strength, which may result in a condition known as sarcopenia, leading to a decline in physical performance, loss of independence and reduced quality of life. While the cause of impaired physical functioning observed in elderly populations appears to be multifactorial, recent evidence suggests that age-associated alterations in gut microbiota could be a contributing factor. The primary objective will be to assess the effects of a dietary synbiotic formulation on sarcopenia-related functional outcomes such as handgrip strength, gait speed and physical performance within older individuals living independently. The secondary objective will be to examine associations between changes in gut microbiota composition, functional performance and lean muscle mass.

METHODS

Seventy-four elderly (60-85 years) participants will be randomized in a double-blind, placebo-controlled fashion to either an intervention or control group. The intervention group (n = 37) will receive oral synbiotic formulation daily for 16 weeks. The control group (n = 37) will receive placebo. Assessments of physical performance (including Short Physical Performance Battery, handgrip strength and timed up-and-go tests) and muscle ultrasonography will be performed at 4 time points (baseline and weeks 8, 16 and 20). Likewise, body composition via bioelectric impedance analysis and blood and stool samples will be collected at each time point. Dual-energy X-ray absorptiometry will be performed at baseline and week 16. The primary outcomes will be between-group changes in physical performance from baseline to 16 weeks. Secondary outcomes include changes in body composition, muscle mass and architecture, fecal microbiota composition and diversity, and fecal and plasma metabolomics.

DISCUSSION

Gut-modulating supplements appear to be effective in modifying gut microbiota composition in healthy older adults. However, it is unclear whether these changes translate into functional and/or health improvements. In the present study, we will investigate the effects of a synbiotic formulation on measures of physical performance, strength and muscle health in healthy older populations.

TRIAL REGISTRATION

This study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622000652774) in May 2022.

The association of alcohol consumption with the risk of sarcopenia: a dose-response meta-analysis

Background: Sarcopenia is defined as a progressive loss of skeletal muscle mass plus a decline in muscle strength and/or reduced physical performance with advancing age. The results of current studies on the relationship between drinking and sarcopenia remain controversial.Objectives: The aim of this meta-analysis was to evaluate the association of alcohol consumption with the risk of sarcopenia.Methods: Systematic searches were conducted without language restrictions from the beginning of each database to September 20, 2023 on PubMed, Embase, Cochrane Library, Web of Science, Wanfang Data, Chinese BioMedical Literature, and China national knowledge infrastructure databases. Meta-analysis was conducted to pool the study-specific odds ratios (ORs) with 95% confidence interval (CI).Results: Sixty-two studies with 454,643 participants were enrolled. The meta-analysis of proportions revealed that alcohol consumption was not associated with the presence of sarcopenia, with a pooled OR of 0.964 (95% CI = 0.912-1.019). Further subgroup analysis indicated that alcohol consumption was correlated with lower risk of sarcopenia in men (OR = 0.763; 95% CI = 0.622-0.938; P = .010). The nonlinear dose-response analysis suggested a J-shaped association between alcohol consumption and the risk of sarcopenia, with a nadir at the amounts of alcohol consumption of 6.6 grams/day (OR = 0.765; 95% CI = 0.608-0.957; P < .05).Conclusions: The results of this meta-analysis indicate that alcohol consumption is not a risk factor for the development of sarcopenia. Any suggestion of a putative protective effect of alcohol should be treated with caution, particularly in light of the overall lack of relationship reported in the present comprehensive meta-analysis.

Musculoskeletal crosstalk in chronic obstructive pulmonary disease and comorbidities: Emerging roles and therapeutic potentials

Chronic Obstructive Pulmonary Disease (COPD) is a multifaceted respiratory disorder characterized by progressive airflow limitation and systemic implications. It has become increasingly apparent that COPD exerts its influence far beyond the respiratory system, extending its impact to various organ systems. Among these, the musculoskeletal system emerges as a central player in both the pathogenesis and management of COPD and its associated comorbidities. Muscle dysfunction and osteoporosis are prevalent musculoskeletal disorders in COPD patients, leading to a substantial decline in exercise capacity and overall health. These manifestations are influenced by systemic inflammation, oxidative stress, and hormonal imbalances, all hallmarks of COPD. Recent research has uncovered an intricate interplay between COPD and musculoskeletal comorbidities, suggesting that muscle and bone tissues may cross-communicate through the release of signalling molecules, known as "myokines" and "osteokines". We explored this dynamic relationship, with a particular focus on the role of the immune system in mediating the cross-communication between muscle and bone in COPD. Moreover, we delved into existing and emerging therapeutic strategies for managing musculoskeletal disorders in COPD. It underscores the development of personalized treatment approaches that target both the respiratory and musculoskeletal aspects of COPD, offering the promise of improved well-being and quality of life for individuals grappling with this complex condition. This comprehensive review underscores the significance of recognizing the profound impact of COPD on the musculoskeletal system and its comorbidities. By unravelling the intricate connections between these systems and exploring innovative treatment avenues, we can aspire to enhance the overall care and outcomes for COPD patients, ultimately offering hope for improved health and well-being.

Radiopharmaceuticals for Skeletal Muscle PET Imaging

The skeletal muscles account for approximately 40% of the body weight and are crucial in movement, nutrient absorption, and energy metabolism. Muscle loss and decline in function cause a decrease in the quality of life of patients and the elderly, leading to complications that require early diagnosis. Positron emission tomography/computed tomography (PET/CT) offers non-invasive, high-resolution visualization of tissues. It has emerged as a promising alternative to invasive diagnostic methods and is attracting attention as a tool for assessing muscle function and imaging muscle diseases. Effective imaging of muscle function and pathology relies on appropriate radiopharmaceuticals that target key aspects of muscle metabolism, such as glucose uptake, adenosine triphosphate (ATP) production, and the oxidation of fat and carbohydrates. In this review, we describe how [18F]fluoro-2-deoxy-D-glucose ([18F]FDG), [18F]fluorocholine ([18F]FCH), [11C]acetate, and [15O]water ([15O]H2O) are suitable radiopharmaceuticals for diagnostic imaging of skeletal muscles.

Effect of resistance circuit training on comprehensive health indicators in older adults: a systematic review and meta-analysis

The aging process leads to the degeneration of body structure and function. The objective of this study is to conduct a systematic review and meta-analysis of the effects of resistance circuit training (RCT) on comprehensive health indicators of older adults. PubMed, Embase, and Web of Science were searched until August 2023. Primary outcomes were body composition, muscle strength, cardiorespiratory endurance, blood pressure, and functional autonomy. Muscle function and exercise intensity subgroups were analyzed. RCT reduces body fat (MD = - 5.39 kg, 95% CI - 10.48 to - 0.29), BMI (MD = - 1.22, 95% CI - 2.17 to - 0.26), and body weight (MD = - 1.28 kg, 95% CI - 1.78 to - 0.78), and increases lean body mass (MD = 1.42 kg, 95% CI 0.83-2.01) in older adults. It improves upper limb strength (SMD = 2.09, 95% CI 1.7-2.48), lower limb strength (SMD = 2.03, 95% CI 1.56-2.51), cardiorespiratory endurance (MD = 94 m, 95% CI 25.69-162.67), and functional autonomy (MD = - 1.35, 95% CI - 1.73 to - 0.96). High-intensity RCT benefits BMI and body weight, while low-intensity exercise reduces blood pressure. RCT improves muscle function in push, pull, hip, and knee movements in older adults. RCT improves body composition, muscle strength, cardiorespiratory endurance, blood pressure, and functional autonomy in older adults. High-intensity training is superior for body composition, while moderate to low intensity training is more effective for lowering blood pressure.

Sarcopenia and adipose tissue evaluation by artificial intelligence predicts the overall survival after TAVI

Sarcopenia is a serious systemic disease that reduces overall survival. TAVI is selectively performed in patients with severe aortic stenosis who are not indicated for open cardiac surgery due to severe polymorbidity. Artificial intelligence-assisted body composition assessment from available CT scans appears to be a simple tool to stratify these patients into low and high risk based on future estimates of all-cause mortality. Within our study, the segmentation of preprocedural CT scans at the level of the lumbar third vertebra in patients undergoing TAVI was performed using a neural network (AutoMATiCA). The obtained parameters (area and density of skeletal muscles and intramuscular, visceral, and subcutaneous adipose tissue) were analyzed using Cox univariate and multivariable models for continuous and categorical variables to assess the relation of selected variables with all-cause mortality. 866 patients were included (median(interquartile range)): age 79.7 (74.9-83.3) years; BMI 28.9 (25.9-32.6) kg/m2. Survival analysis was performed on all automatically obtained parameters of muscle and fat density and area. Skeletal muscle index (SMI in cm2/m2), visceral (VAT in HU) and subcutaneous adipose tissue (SAT in HU) density predicted the all-cause mortality in patients after TAVI expressed as hazard ratio (HR) with 95% confidence interval (CI): SMI HR 0.986, 95% CI (0.975-0.996); VAT 1.015 (1.002-1.028) and SAT 1.014 (1.004-1.023), all p < 0.05. Automatic body composition assessment can estimate higher all-cause mortality risk in patients after TAVI, which may be useful in preoperative clinical reasoning and stratification of patients.

Reliability, costs, and radiation dose of dual-energy X-ray absorptiometry in diagnosis of radiologic sarcopenia in surgically menopausal women

OBJECTIVE

The aim of this study was to evaluate and compare reliability, costs, and radiation dose of dual-energy X-ray absorptiometry (DXA) to MRI and CT in measuring muscle mass for the diagnosis of sarcopenia.

METHODS

Thirty-four consecutive DXA scans performed in surgically menopausal women from November 2019 until March 2020 were analyzed by two observers. Observers analyzed muscle mass of the lower limbs in every scan twice. Reliability was assessed by calculating inter- and intra-observer variability. Reliability from CT and MRI as well as radiation dose from CT and DXA were collected from literature. Costs for each type of scan were calculated according to the guidelines for economic evaluation of the Dutch National Health Care Institute.

RESULTS

The 34 participants had a median age of 58 years (IQR 53-65) and a median body mass index of 24.6 (IQR 21.7-29.7). Inter-observer variability had an intraclass correlation coefficient (ICC) of 0.997 (95% CI 0.994-0.998) with a relative variability of 0.037 ± 0.022%. Regarding intra-observer variability, observer 1 had an ICC of 0.998 (95% CI 0.996-0.999) with a relative variability of 0.019 ± 0.016% and observer 2 had an ICC of 0.997 (95% CI 0.993-0.998) with a relative variability of 0.016 ± 0.011%. DXA costs were €62, CT €77, and MRI €195. The estimated radiation dose of CT was 2.5-3.0 mSv, for DXA this was 2-4 µSv.

CONCLUSIONS

DXA has lower costs and a lower radiation dose, with low inter- and intra-observer variability, compared to CT and MRI for assessing lower limb muscle mass.

TRIAL REGISTRATION

Netherlands Trial Register; NL8068.

CRITICAL RELEVANCE STATEMENT

DXA is a good alternative for CT and MRI in assessing lower limb muscle mass, with lower costs and lower radiation dose, while inter-observer and intra-observer variability are low.

KEY POINTS

• Screening for sarcopenia should be optimized as the population ages. • DXA outperformed CT and MRI in the measured metrics. • DXA validity should be further evaluated as an alternative to CT and MRI for sarcopenia evaluation.

Irisin alters D-galactose-induced apoptosis by increasing caveolin-1 expression in C2C12 myoblasts and skeletal muscle fibroblasts

Muscle atrophy and skeletal muscle fibrosis are significant pathological manifestations of primary sarcopenia. The regulation of C2C12 myoblast and skeletal muscle fibroblast apoptosis is associated with these pathological changes. Previous studies have indicated that irisin, the cleaved form of fibronectin type III domain-containing protein 5 (FNDC5), can alleviate primary sarcopenia. However, the mechanisms of the effect of irisin in age-related apoptosis remain unknown. Our present research aimed to explore the effect of irisin and the underlying mechanism of D-galactose (D-gal)-induced apoptosis in skeletal muscle fibroblasts and C2C12 myoblasts. We found the opposite effects of D-gal on C2C12 myoblasts and fibroblasts. We also found that irisin suppressed C2C12 cell apoptosis and promoted fibroblast apoptosis. Mechanistically, irisin altered D-gal-induced apoptosis by increasing caveolin-1 expression. Taken together, these findings further demonstrated that irisin is a potential agent that can treat aged-relative muscle atrophy and fibrosis.