Bimagrumab vs Optimized Standard of Care for Treatment of Sarcopenia in Community-Dwelling Older Adults: A Randomized Clinical Trial

Efficacy and Safety of GLP-1 Medicines for Type 2 Diabetes and Obesity

The development of glucagon-like peptide 1 receptor agonists (GLP-1RA) for type 2 diabetes and obesity was followed by data establishing the cardiorenal benefits of GLP-1RA in select patient populations. In ongoing trials investigators are interrogating the efficacy of these agents for new indications, including metabolic liver disease, peripheral artery disease, Parkinson disease, and Alzheimer disease. The success of GLP-1-based medicines has spurred the development of new molecular entities and combinations with unique pharmacokinetic and pharmacodynamic profiles, exemplified by tirzepatide, a GIP-GLP-1 receptor coagonist. Simultaneously, investigational molecules such as maritide block the GIP and activate the GLP-1 receptor, whereas retatrutide and survodutide enable simultaneous activation of the glucagon and GLP-1 receptors. Here I highlight evidence establishing the efficacy of GLP-1-based medicines, while discussing data that inform safety, focusing on muscle strength, bone density and fractures, exercise capacity, gastrointestinal motility, retained gastric contents and anesthesia, pancreatic and biliary tract disorders, and the risk of cancer. Rapid progress in development of highly efficacious GLP-1 medicines, and anticipated differentiation of newer agents in subsets of metabolic disorders, will provide greater opportunities for use of personalized medicine approaches to improve the health of people living with cardiometabolic disorders.

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.

Therapeutic applications and challenges in myostatin inhibition for enhanced skeletal muscle mass and functions

Myostatin, a potent negative regulator of skeletal muscle mass, has garnered significant attention as a therapeutic target for muscle dystrophies. Despite extensive research and promising preclinical results, clinical trials targeting myostatin inhibition in muscle dystrophies have failed to yield substantial improvements in muscle function or fitness in patients. This review details the mechanisms behind myostatin's function and the various inhibitors that have been tested preclinically and clinically. It also examines the challenges encountered in clinical translation, including issues with drug specificity, differences in serum myostatin concentrations between animal models and humans, and the necessity of neural input for functional improvements. Additionally, we explore promising avenues of research beyond muscle dystrophies, particularly in the treatment of metabolic syndromes and orthopedic disorders. Insights from these alternative applications suggest that myostatin inhibition may hold the potential for addressing a broader range of pathologies, providing new directions for therapeutic development.

Emerging Targets and Treatments for Sarcopenia: A Narrative Review

BACKGROUND

Sarcopenia is characterized by the progressive loss of skeletal muscle mass, strength, and function, significantly impacting overall health and quality of life in older adults. This narrative review explores emerging targets and potential treatments for sarcopenia, aiming to provide a comprehensive overview of current and prospective interventions.

METHODS

The review synthesizes current literature on sarcopenia treatment, focusing on recent advancements in muscle regeneration, mitochondrial function, nutritional strategies, and the muscle-microbiome axis. Additionally, pharmacological and lifestyle interventions targeting anabolic resistance and neuromuscular junction integrity are discussed.

RESULTS

Resistance training and adequate protein intake remain the cornerstone of sarcopenia management. Emerging strategies include targeting muscle regeneration through myosatellite cell activation, signaling pathways, and chronic inflammation control. Gene editing, stem cell therapy, and microRNA modulation show promise in enhancing muscle repair. Addressing mitochondrial dysfunction through interventions aimed at improving biogenesis, ATP production, and reducing oxidative stress is also highlighted. Nutritional strategies such as leucine supplementation and anti-inflammatory nutrients, along with dietary modifications and probiotics targeting the muscle-microbiome interplay, are discussed as potential treatment options. Hydration and muscle-water balance are emphasized as critical in maintaining muscle health in older adults.

CONCLUSIONS

A combination of resistance training, nutrition, and emerging therapeutic interventions holds potential to significantly improve muscle function and overall health in the aging population. This review provides a detailed exploration of both established and novel approaches for the prevention and management of sarcopenia, highlighting the need for further research to optimize these strategies.

Relative Energy Deficiency in Sport (REDs): Endocrine Manifestations, Pathophysiology and Treatments

Research on lean, energy-deficient athletic and military cohorts has broadened the concept of the Female Athlete Triad into the Relative Energy Deficiency in Sport (REDs) syndrome. REDs represents a spectrum of abnormalities induced by low energy availability (LEA), which serves as the underlying cause of all symptoms described within the REDs concept, affecting exercising populations of either biological sex. Both short- and long-term LEA, in conjunction with other moderating factors, may produce a multitude of maladaptive changes that impair various physiological systems and adversely affect health, well-being, and sport performance. Consequently, the comprehensive definition of REDs encompasses a broad spectrum of physiological sequelae and adverse clinical outcomes related to LEA, such as neuroendocrine, bone, immune, and hematological effects, ultimately resulting in compromised health and performance. In this review, we discuss the pathophysiology of REDs and associated disorders. We briefly examine current treatment recommendations for REDs, primarily focusing on nonpharmacological, behavioral, and lifestyle modifications that target its underlying cause-energy deficit. We also discuss treatment approaches aimed at managing symptoms, such as menstrual dysfunction and bone stress injuries, and explore potential novel treatments that target the underlying physiology, emphasizing the roles of leptin and the activin-follistatin-inhibin axis, the roles of which remain to be fully elucidated, in the pathophysiology and management of REDs. In the near future, novel therapies leveraging our emerging understanding of molecules and physiological axes underlying energy availability or lack thereof may restore LEA-related abnormalities, thus preventing and/or treating REDs-related health complications, such as stress fractures, and improving performance.

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.

The distinct impacts of sarcopenic and dynapenic obesity on mortality in middle-aged and older adults based on different adiposity metrics: Results from I-Lan Longitudinal Aging Study

BACKGROUND & AIMS

Sarcopenic obesity (SO) and dynapenic obesity (DO) represent two manifestations of excessive fat accumulation concurrent with compromised muscle mass and function, thereby necessitating an examination of their implications for health. This study aims to investigate the relationship between SO/DO and mortality, taking into account various adiposity measures and existing sarcopenia criteria, with further stratified analyses based on age and gender.

METHODS

The study sample comprised 1779 older adults residing in the community from the I-Lan Longitudinal Aging Study (ILAS). Body composition was assessed via dual-energy X-ray absorptiometry. The diagnosis of sarcopenia was adhered to the 2019 consensus of the Asian Working Group for Sarcopenia, while adiposity was measured by waist circumference (WC), body mass index (BMI), and fat percentage. SO/DO was defined as the coexistence of sarcopenia/dynapenia and obesity. Multivariate Cox proportional hazard regression models were adopted to examine the association between SO or DO, defined by WC, BMI, fat percentage, and mortality.

RESULTS

This 11-year follow-up study of 1779 participants aged 63.9 ± 9.2 years involved 15,068 person-years and 229 deaths. WC-defined SO (HR 1.9, 95% CI 1.1-3.3, p = 0.021) and WC-defined DO (HR 1.4, 95% CI 1.1-1.9, p = 0.022) significantly increased mortality risk, whereas definitions employing alternative adiposity metrics exhibited no statistical significance. WC-defined SO was associated with increased risk of mortality among middle-aged adults, while WC-defined DO was associated with increased risk of mortality among older adults. In sex-specific analysis, WC-defined DO was also associated with increased risk of mortality in men (HR 1.6, 95% CI 1.1-2.4, p = 0.019), while defined by other measurements showed no associations in both sexes.

CONCLUSIONS

The study identified a significant link between SO/DO, defined by WC, and an 11-year mortality risk, advocating for WC-defined adiposity as an obesity measure and personalized interventions considering SO and DO's distinct impacts on mortality in middle-aged and older adults.

Myostatin regulates energy homeostasis through autocrine- and paracrine-mediated microenvironment communication

Myostatin (MSTN) has long been recognized as a critical regulator of muscle mass. Recently, there has been increasing interest in its role in metabolism. In our study, we specifically knocked out MSTN in brown adipose tissue (BAT) from mice (MSTNΔUCP1) and found that the mice gained more weight than did controls when fed a high-fat diet, with progressive hepatosteatosis and impaired skeletal muscle activity. RNA-Seq analysis indicated signatures of mitochondrial dysfunction and inflammation in the MSTN-ablated BAT. Further studies demonstrated that Kruppel-like factor 4 (KLF4) was responsible for the metabolic phenotypes observed, whereas fibroblast growth factor 21 (FGF21) contributed to the microenvironment communication between adipocytes and macrophages induced by the loss of MSTN. Moreover, the MSTN/SMAD2/3-p38 signaling pathway mediated the expression of KLF4 and FGF21 in adipocytes. In summary, our findings suggest that brown adipocyte-derived MSTN regulated BAT thermogenesis via autocrine and paracrine effects on adipocytes or macrophages, ultimately regulating systemic energy homeostasis.

Lost in translation: challenges of current pharmacotherapy for sarcopenia

A healthy lifespan relies on independent living, in which active skeletal muscle is a critical element. The cost of not recognizing and acting earlier on unhealthy or aging muscle could be detrimental, since muscular weakness is inversely associated with all-cause mortality. Sarcopenia is characterized by a decline in skeletal muscle mass and strength and is associated with aging. Exercise is the only effective therapy to delay sarcopenia development and improve muscle health in older adults. Although numerous interventions have been proposed to reduce sarcopenia, none has yet succeeded in clinical trials. This review evaluates the biological gap between recent clinical trials targeting sarcopenia and the preclinical studies on which they are based, and suggests an alternative approach to bridge the discrepancy.

Biomarkers of frailty

Several biomarkers have been proposed to identify frailty, a multisystemic age-related syndrome. However, the complex pathophysiology and the absence of a consensus on a comprehensive and universal definition make it challenging to pinpoint a singular biomarker or set of biomarkers that conclusively characterize frailty. This review delves into the main laboratory biomarkers, placing special emphasis on those associated with various pathways closely tied to the frailty condition, such as inflammation, oxidative stress, mitochondrial dysfunction, metabolic and endocrine alterations and microRNA. Additionally, we provide a summary of different clinical biomarkers encompassing different tools that have been proposed to assess frailty. We further address various imaging biomarkers such as Dual Energy X-ray Absorptiometry, Bioelectrical Impedance analysis, Computed Tomography and Magnetic Resonance Imaging, Ultrasound and D3 Creatine dilution. Intervention to treat frailty, including non-pharmacological ones, especially those involving physical exercise and nutrition, and pharmacological interventions, that include those targeting specific mechanisms such as myostatin inhibitors, insulin sensitizer metformin and with special relevance for hormonal treatments are mentioned. We further address the levels of different biomarkers in monitoring the potential positive effects of some of these interventions. Despite the availability of numerous biomarkers, their performance and usefulness in the clinical arena are far from being satisfactory. Considering the multicausality of frailty, there is an increasing need to assess the role of sets of biomarkers and the combination between laboratory, clinical and image biomarkers, in terms of sensitivity, specificity and predictive values for the diagnosis and prognosis of the different outcomes of frailty to improve detection and monitoring of older people with frailty or at risk of developing it, being this a need in the everyday clinical practice.

Emerging drugs for the treatment of sarcopenia in cirrhosis of the liver

INTRODUCTION

Malnutrition and sarcopenia are common and impact the prognosis in patients with liver cirrhosis. The etiology is multifactorial and includes periods of reduced caloric intake, increased catabolism and direct molecular mechanisms that inhibit muscle synthesis. Although these conditions are widely acknowledged, and there is a growing interest in their diagnosis, robust evidence regarding the treatment and reversibility of these conditions is still lacking.

AREAS COVERED

We have explored the current evidence on the pharmacological treatment of sarcopenia in patients with cirrhosis. Additionally, we have searched for drugs already in use and ongoing trials for other chronic diseases.

EXPERT OPINION

The current guidelines recommend the use of a protein-adequate diet and moderate physical activity for treating sarcopenia in patients with cirrhosis. Currently, robust evidence is derived only from the supplementation of Branched-Chain Amino Acids, capable of increasing muscle mass and function. There are many drugs targeting various pathways that contribute to sarcopenia. However, evidence is sporadic and insufficient to suggest their use in clinical practice.Novel drugs specifically designed to enhance muscle mass and function should be developed. Finally, gender significantly influences the type of muscle alteration and therapeutic mechanisms; therefore, future studies should be designed taking gender differences into consideration.

Sarcopenic obesity in older adults: a clinical overview

Sarcopenic obesity is characterized by a concurrent decline in muscle mass and function, along with increased adipose tissue. Sarcopenic obesity is a growing concern in older adults owing to significant health consequences, including implications for mortality, comorbidities and risk of developing geriatric syndromes. A 2022 consensus statement established a new definition and diagnostic criteria for sarcopenic obesity. The pathophysiology of this condition involves a complex interplay between muscle, adipose tissue, hormonal changes, inflammation, oxidative stress and lifestyle factors, among others. Sarcopenic obesity is treated with a range of management approaches, such as lifestyle interventions, exercise, nutrition and medical therapies. Emerging therapies that were developed for treating other conditions may be relevant to sarcopenic obesity, including novel pharmacological agents and personalized approaches such as precision medicine. In this Review, we synthesize the current knowledge of the clinical importance of sarcopenic obesity, its assessment and diagnosis, along with current and emerging management strategies.

Emerging Therapeutic Strategies in Sarcopenia: An Updated Review on Pathogenesis and Treatment Advances

Sarcopenia is a prevalent degenerative skeletal muscle condition in the elderly population, posing a tremendous burden on diseased individuals and healthcare systems worldwide. Conventionally, sarcopenia is currently managed through nutritional interventions, physical therapy, and lifestyle modification, with no pharmaceutical agents being approved for specific use in this disease. As the pathogenesis of sarcopenia is still poorly understood and there is no treatment recognized as universally effective, recent research efforts have been directed at better comprehending this illness and diversifying treatment strategies. In this respect, this paper overviews the new advances in sarcopenia treatment in correlation with its underlying mechanisms. Specifically, this review creates an updated framework for sarcopenia, describing its etiology, pathogenesis, risk factors, and conventional treatments, further discussing emerging therapeutic approaches like new drug formulations, drug delivery systems, stem cell therapies, and tissue-engineered scaffolds in more detail.

GDF5 as a rejuvenating treatment for age-related neuromuscular failure

Sarcopenia involves a progressive loss of skeletal muscle force, quality and mass during ageing, which results in increased inability and death; however, no cure has been established thus far. Growth differentiation factor 5 (GDF5) has been described to modulate muscle mass maintenance in various contexts. For our proof of concept, we overexpressed GDF5 by AAV vector injection in Tibialis Anterior (TA) muscle of adult aged (20 months) mice and performed molecular and functional analysis of skeletal muscle. We analysed human Vastus Lateralis muscle biopsies from adult young (21-42 years) and aged (77-80 years) donors, quantifying the molecular markers modified by GDF5 overexpression (OE) in mouse muscle. We validated the major effects of GDF5 overexpression using human immortalized myotubes and Schwann Cells (SCs). We established a pre-clinical study by treating chronically (for 4 months) aged mice using recombinant GDF5 protein (rGDF5) in systemic administration and evaluated the long-term effect of this treatment on muscle mass and function. Here, we demonstrated that GDF5 OE in the old TAs promoted an increase of 16.5% of muscle weight (P = 0.0471) associated with a higher percentage of 5000-6000 µm2 large fibres (P = 0.0211), without the induction of muscle regeneration. Muscle mass gain was associated with an amelioration of 26.8% of rate of force generation (P = 0.0330) and a better neuromuscular connectivity (P = 0.0098). Moreover, GDF5 OE preserved neuromuscular junction (NMJ) morphology (38.5% of nerve terminal area increase, P < 0.0001) and stimulated the expression of re-innervation-related genes, in particular markers of SCs (fold change 3.19 for S100b gene expression, P = 0.0101). To further characterize the molecular events induced by GDF5 OE during ageing, we performed a genome-wide transcriptomic analysis of treated muscles and showed that this factor leads to a "rejuvenating" transcriptomic signature in aged mice, as 42% of the transcripts dysregulated by ageing reverted to youthful expression levels upon GDF5 OE (P < 0.05). Towards a pre-clinical approach, we performed a long-term systemic treatment using rGDF5 and showed its effectiveness in counteracting age-related muscle wasting, improving muscle function (17,8% of absolute maximal force increase, P = 0.0079), ensuring neuromuscular connectivity and preventing NMJ degeneration (7,96% of AchR area increase, P = 0.0125). In addition, in human muscle biopsies, we found the same age-related alterations than those observed in mice and improved by GDF5 and reproduced its major effects on human cells, suggesting this treatment as efficient in humans. Overall, these data provide a foundation to examine the curative potential of GDF5 drug in clinical trials for sarcopenia and, eventually, other neuromuscular diseases.

Advances in sarcopenia: mechanisms, therapeutic targets, and intervention strategies

Sarcopenia is a multifactorial condition characterized by loss of muscle mass. It poses significant health risks in older adults worldwide. Both pharmacological and non-pharmacological approaches are reported to address this disease. Certain dietary patterns, such as adequate energy intake and essential amino acids, have shown positive outcomes in preserving muscle function. Various medications, including myostatin inhibitors, growth hormones, and activin type II receptor inhibitors, have been evaluated for their effectiveness in managing sarcopenia. However, it is important to consider the variable efficacy and potential side effects associated with these treatments. There are currently no drugs approved by the Food and Drug Administration for sarcopenia. The ongoing research aims to develop more effective strategies in the future. Our review of research on disease mechanisms and drug development will be a valuable contribution to future research endeavors.

Muscle strength and non-alcoholic fatty liver disease/metabolic-associated fatty liver disease

This editorial comments on an article published in a recent issue of World Journal of Gastroenterology, entitled “Association of low muscle strength with metabolic dysfunction-associated fatty liver disease: A nationwide study”. We focused on the association between muscle strength and the incidence of non-alcoholic fatty liver disease (NAFLD) and metabolic-associated fatty liver disease (MAFLD), as well as the mechanisms underlying the correlation and related clinical applications. NAFLD, which is now redefined as MAFLD, is one of the most common chronic liver diseases globally with an increasing prevalence and is characterized by malnutrition, which may contribute to decreased muscle strength. Reduction of muscle strength reportedly has a pathogenesis similar to that of NAFLD/ MAFLD, including insulin resistance, inflammation, sedentary behavior, as well as insufficient vitamin D. Multiple studies have focused on the relationship between sarcopenia or muscle strength and NAFLD. However, studies investigating the relationship between muscle strength and MAFLD are limited. Owing to the shortage of specific medications for NAFLD/MAFLD treatment, early detection is essential. Furthermore, the relationship between muscle strength and NAFLD/MAFLD suggests that improvements in muscle strength may have an impact on disease prevention and may provide novel insights into treatments including dietary therapy, as well as tailored physical activity.

The Current Landscape of Pharmacotherapies for Sarcopenia

Sarcopenia is a skeletal muscle disorder characterized by progressive and generalized decline in muscle mass and function. Although it is mostly known as an age-related disorder, it can also occur secondary to systemic diseases such as malignancy or organ failure. It has demonstrated a significant relationship with adverse outcomes, e.g., falls, disabilities, and even mortality. Several breakthroughs have been made to find a pharmaceutical therapy for sarcopenia over the years, and some have come up with promising findings. Yet still no drug has been approved for its treatment. The key factor that makes finding an effective pharmacotherapy so challenging is the general paradigm of standalone/single diseases, traditionally adopted in medicine. Today, it is well known that sarcopenia is a complex disorder caused by multiple factors, e.g., imbalance in protein turnover, satellite cell and mitochondrial dysfunction, hormonal changes, low-grade inflammation, senescence, anorexia of aging, and behavioral factors such as low physical activity. Therefore, pharmaceuticals, either alone or combined, that exhibit multiple actions on these factors simultaneously will likely be the drug of choice to manage sarcopenia. Among various drug options explored throughout the years, testosterone still has the most cumulated evidence regarding its effects on muscle health and its safety. A mas receptor agonist, BIO101, stands out as a recent promising pharmaceutical. In addition to the conventional strategies (i.e., nutritional support and physical exercise), therapeutics with multiple targets of action or combination of multiple therapeutics with different targets/modes of action appear to promise greater benefit for the prevention and treatment of sarcopenia.

Impact of low skeletal muscle mass on postoperative complications in head and neck cancer patients undergoing free flap reconstructive surgery - A systematic review and meta-analysis

Low skeletal muscle mass is emerging as an adverse predictive and prognostic factor in cancer patients. The use of this parameter as a risk factor for complications after surgery is not currently used in clinical practice. This meta-analysis aims to assess the association of low skeletal muscle mass defined by radiological criteria and complications after reconstructive microsurgery in head and neck cancer patients. A systematic review for articles was performed using the PubMed, EMBASE database and by manual search. Articles that assessed low skeletal muscle mass and its impact on postoperative complications in head and neck cancer patients undergoing free flap surgery were selected. Pooled estimates of postoperative outcome data were calculated by extracting the odds ratio (OR) and 95% confidence interval (CI). The search strategy returned with 6 studies meeting the inclusion criteria. A total of 1082 patients were analyzed. The prevalence of low skeletal muscle mass between studies ranged from 24.6% to 61.5%. The meta-analysis showed an OR for complications after surgery of 2.42 (95% CI 1.53-3.32, p = 0.00). The study therefore concludes that skeletal muscle mass is an independent risk factor for postoperative complications in head and neck cancer reconstructive surgery patients. This argues for implementing screening for low skeletal muscle in preoperative management to optimize surgical decision making.

Current and investigational medications for the treatment of sarcopenia

Sarcopenia, defined as the loss of muscle mass and function, is a widely prevalent and severe condition in older adults. Since 2016, it is recognized as a disease. Strength exercise training and nutritional support are the frontline treatment of sarcopenia, with no drug currently approved for this indication. However, new therapeutic options are emerging. In this review, we evidenced that only very few trials have focused on sarcopenia/sarcopenic patients. Most drug trials were performed in different clinical older populations (e.g., men with hypogonadism, post-menopausal women at risk for osteoporosis), and their efficacy were tested separately on the components of sarcopenia (muscle mass, muscle strength and physical performances). Results from trials testing the effects of Testosterone, Selective Androgen Receptor Modulators (SARMs), Estrogen, Dehydroepiandrosterone (DHEA), Insulin-like Growth Factor-1 (IGF-1), Growth Hormone (GH), GH Secretagogue (GHS), drug targeting Myostatin and Activin receptor pathway, Vitamin D, Angiotensin Converting Enzyme inhibitors (ACEi) and Angiotensin Receptor Blockers (ARBs), or β-blockers, were compiled. Although some drugs have been effective in improving muscle mass and/or strength, this was not translated into clinically relevant improvements on physical performance. Finally, some promising molecules investigated in on-going clinical trials and in pre-clinical phase were summarized, including apelin and irisin.

Is moderate resistance training adequate for older adults with sarcopenia? A systematic review and network meta-analysis of RCTs

BACKGROUND

Resistance training (RT) and nutritional supplementation are recommended for the management of sarcopenia in older adults. However, optimal RT intensity for the treatment of sarcopenia has not been well investigated.

METHODS

This network meta-analysis aims to determine the comparative effectiveness of interventions for sarcopenia, taking RT intensity into consideration. RT intensity was classified into light-to-moderate intensity RT(LMRT), moderate intensity RT(MRT), and moderate-to-vigorous intensity RT(MVRT) based on percentage of one repetition maximum (%1RM) and/or rating of perceived exertion.

RESULTS

A total of 50 RCTs (N = 4,085) were included after screening 3,485 articles. The results confirmed that RT with or without nutrition was positively associated with improved measures of muscle strength and physical performance. Regarding RT intensity, LMRT only demonstrated positive effects on hand grip (aerobic training + LMRT + nutrition: mean difference [MD] = 2.88; 95% credential intervals [CrI] = 0.43,5.32). MRT provided benefits on improvement in the 30-s chair stand test (repetitions) (MRT: MD = 2.98, 95% CrI = 0.35,5.59), timed up and go test (MRT: MD = -1.74, 95% CrI: = -3.34,-0.56), hand grip (MRT: MD = 2.44; 95% CrI = 0.03,5.70), and leg press (MRT: MD = 8.36; 95% CrI = 1.87,13.4). MVRT also improved chair stand test repetitions (MVRT: MD = 5.64, 95% CrI = 0.14,11.4), gait speed (MVRT + nutrition: MD = 0.21, 95% CrI = 0.003,0.48), appendicular skeletal muscle index (MVRT + nutrition: MD = 0.25, 95% CrI = 0.01,0.5), and leg press (MVRT: MD = 14.7, 95% CrI: 5.96,22.4; MVRT + nutrition: MD = 17.8, 95% CrI: 7.55,28.6).

CONCLUSION

MVRT had greater benefits on muscle mass, lower extremity strength, and physical performance compared to MRT. Increasing RT intensity may be recommended for sarcopenic older adults.

Age Is Just a Number: Progress and Obstacles in the Discovery of New Candidate Drugs for Sarcopenia

Sarcopenia is a disease characterized by the progressive loss of skeletal muscle mass and function that occurs with aging. The progression of sarcopenia is correlated with the onset of physical disability, the inability to live independently, and increased mortality. Due to global increases in lifespan and demographic aging in developed countries, sarcopenia has become a major socioeconomic burden. Clinical therapies for sarcopenia are based on physical therapy and nutritional support, although these may suffer from low adherence and variable outcomes. There are currently no clinically approved drugs for sarcopenia. Consequently, there is a large amount of pre-clinical research focusing on discovering new candidate drugs and novel targets. In this review, recent progress in this research will be discussed, along with the challenges that may preclude successful translational research in the clinic. The types of drugs examined include mitochondria-targeting compounds, anti-diabetes agents, small molecules that target non-coding RNAs, protein therapeutics, natural products, and repositioning candidates. In light of the large number of drugs and targets being reported, it can be envisioned that clinically approved pharmaceuticals to prevent the progression or even mitigate sarcopenia may be within reach.

Type 2 Diabetes Mellitus and Sarcopenia as Comorbid Chronic Diseases in Older Adults: Established and Emerging Treatments and Therapies

Type 2 diabetes mellitus (T2DM) and sarcopenia (low skeletal muscle mass and function) share a bidirectional relationship. The prevalence of these diseases increases with age and they share common risk factors. Skeletal muscle fat infiltration, commonly referred to as myosteatosis, may be a major contributor to both T2DM and sarcopenia in older adults via independent effects on insulin resistance and muscle health. Many strategies to manage T2DM result in energy restriction and subsequent weight loss, and this can lead to significant declines in muscle mass in the absence of resistance exercise, which is also a first-line treatment for sarcopenia. In this review, we highlight recent evidence on established treatments and emerging therapies targeting weight loss and muscle mass and function improvements in older adults with, or at risk of, T2DM and/or sarcopenia. This includes dietary, physical activity and exercise interventions, new generation incretin-based agonists and myostatin-based antagonists, and endoscopic bariatric therapies. We also highlight how digital health technologies and health literacy interventions can increase uptake of, and adherence to, established and emerging treatments and therapies in older adults with T2DM and/or sarcopenia.

Associations Between Circulating Levels of Myostatin and Plasma β-Amyloid 42/40 in a Biracial Cohort of Older Adults

BACKGROUND

Myostatin, a cytokine produced by skeletal muscle, may influence Alzheimer's disease (AD) pathogenesis, but sparse evidence exists in humans. We assessed the association between circulating levels of myostatin at Year 1 and plasma levels of β-amyloid 42/40 at Year 2, a marker of AD pathology, in a biracial cohort of older adults.

METHODS

We studied 403 community-dwelling older adults enrolled in the Health, Aging and Body Composition Study from Memphis, Tennessee, and Pittsburgh, PA. Mean age was 73.8 ± 3 years; 54% were female; and 52% were Black. Serum myostatin levels were measured at Year 1, plasma β-amyloid 42/40 levels in Year 2 (higher ratio indicating lower amyloid load). Multivariable linear regression analyses tested the association of serum myostatin with plasma levels of β-amyloid 42/40 adjusted for computed-tomography-derived thigh muscle cross-sectional area, demographics, APOe4 allele, and risk factors for dementia. We tested for 2-way.interactions between myostatin and race or sex; results were stratified by race and sex.

RESULTS

In multivariable models, myostatin was positively associated with plasma levels of β-amyloid 42/40 (standardized regression coefficient: 0.145, p = .004). Results were significant for white men and women (0.279, p = .009, and 0.221, p = .035, respectively) but not for Black men or women; interactions by race and gender were not statistically significant.

CONCLUSIONS

Higher serum myostatin was associated with lower amyloid burden, independently of APOe4 alleles, muscle area and other established risk factors for dementia. The role of myostatin in AD pathogenesis and the influence of race should be further investigated.

Mitochondria Transplantation from Stem Cells for Mitigating Sarcopenia

Sarcopenia is defined as the age-related loss of muscle mass and function that can lead to prolonged hospital stays and decreased independence. It is a significant health and financial burden for individuals, families, and society as a whole. The accumulation of damaged mitochondria in skeletal muscle contributes to the degeneration of muscles with age. Currently, the treatment of sarcopenia is limited to improving nutrition and physical activity. Studying effective methods to alleviate and treat sarcopenia to improve the quality of life and lifespan of older people is a growing area of interest in geriatric medicine. Therapies targeting mitochondria and restoring mitochondrial function are promising treatment strategies. This article provides an overview of stem cell transplantation for sarcopenia, including the mitochondrial delivery pathway and the protective role of stem cells. It also highlights recent advances in preclinical and clinical research on sarcopenia and presents a new treatment method involving stem cell-derived mitochondrial transplantation, outlining its advantages and challenges.

Muscle wasting: emerging pathways and potential drug targets

Muscle wasting is a serious comorbidity associated with many disorders, including cancer, kidney disease, heart failure, and aging. Progressive loss of skeletal muscle mass negatively influences prognosis and survival, and is often accompanied by frailty and poor quality of life. Clinical trials testing therapeutics against muscle wasting have yielded limited success. Some therapies improved muscle mass in patients without appreciable differences in physical performance. This review article discusses emerging pathways that regulate muscle atrophy, including oncostatin M (OSM) and ectodysplasin A2 (EDA2) receptor (EDA2R) signaling, outcomes of recent clinical trials, and potential drug targets for future therapies.

Sarcopenia in Immune-Mediated Rheumatic Diseases-Review

INTRODUCTION

Sarcopenia is a condition characterized by decreased muscle strength and muscle mass, which can impact physical function. Sarcopenia develops as a consequence of age-related decline (primary sarcopenia) and has a major impact on physical, social, and emotional well-being. In addition, patients with rheumatic diseases may suffer from sarcopenia independently of aging (secondary sarcopenia). Exercise, pharmacological treatments, and nutritional supplementation are some of the strategies used for the management of sarcopenia in the general population. The aim of this review is to summarize the evidence around the prevalence and impact of sarcopenia in patients with rheumatic diseases.

CONCLUSIONS

From our review, we can state that sarcopenia is a common and prevalent condition among the rheumatic diseases. Furthermore, the impacts of sarcopenia are not well-appreciated, and the implementation of treatment strategies has not been widespread. Strategies such as exercise and some pharmacological treatments are effective in improving physical and functional impairment related to these conditions.

FUTURE RESEARCH DIRECTIONS IN THE FIELD

New pharmacological treatments are being actively studied and may contribute in the future to the management of sarcopenia.

Measuring health-related quality of life in sarcopenia: summary of the SarQoL psychometric properties

Patient perspectives are now widely recognized as a key element in the evaluation of health interventions. Therefore, the provision of specific and validated Patient Reported Outcome Measures that emphasize the lived experience of patients suffering from specific diseases is very important. In the field of sarcopenia, the only validated specific health-related quality of life (HRQoL) instrument available is the Sarcopenia Quality of Life questionnaire (SarQoL). This self-administrated HRQoL questionnaire, developed in 2015, consists of 55 items arranged into 22 questions and has currently been translated into 35 languages. Nineteen validation studies performed on SarQoL have consensually confirmed the capacity of SarQoL to detect difference in HRQoL between older people with and without sarcopenia, its reliability and its validity. Two further observational studies have also indicated its responsiveness to change. A short form SarQoL, including only 14 items has further been developed and validated to reduce the potential burden of administration. Research on the psychometric properties of SarQoL questionnaire is still encouraged as the responsiveness to change of SarQoL has not yet been measured in the context of interventional studies, as limited prospective data currently exist and as there is still not cut-off score to define a low HRQoL. In addition, SarQoL has mainly been used in community-dwelling older individuals with sarcopenia and would benefit to be studied in other types of populations. This review aims to provide to researchers, clinicians, regulators, pharmaceutical industries and other stakeholders a clear summary of comprehensive evidence on the SarQoL questionnaire published up to January 2023Query.

Promoting resilience in the face of ageing and disease: The central role of exercise and physical activity

Exercise and physical activity offer clinical benefits across a wide range of both physical and neuropsychological diseases and disabilities in older adults, including syndromes for which pharmacological treatment is either absent or hazardous. However, exercise is vastly under-utilised and rarely fully integrated into aged care and geriatric medicine practice. It is still absent from the core training of most geriatricians and other healthcare professionals, and myths about risks of robust exercise abound. Insufficient physical activity and sedentariness are in fact the lethal conditions. Frailty is not a barrier to exercise, but rather one of the most important reasons to prescribe it. Like any other medical treatment, to prescribe exercise as a drug will require a full understanding of its benefits, dose-response characteristics, modality-specific adaptations, potential risks, and interactions with other treatments. Additionally, exercise prescription should be a mandatory component of training for all healthcare professionals in geriatric medicine and gerontology. This personal view asserts the importance of medication management closely integrated with physical exercise prescription, as well as nutritional support as cornerstone of a coherent and holistic approach to treating both fit and frail older adults. This includes identification and management of drug-exercise interactions, in the same way that we seek out and manage drug-drug interactions and drug-nutrient interactions. Our oldest patients deserve the dignity of our urgent resolve to remember the mission of medicine: the assertion and the assurance of the human potential. Exercise medicine is core to this mission.

Sarcopenia, osteoporosis and frailty

Muscles and bones are intricately connected tissues displaying marked co-variation during development, growth, aging, and in many diseases. While the diagnosis and treatment of osteoporosis are well established in clinical practice, sarcopenia has only been classified internationally as a disease in 2016. Both conditions are associated with an increased risk of adverse health outcomes such as fractures, dysmobility and mortality. Rather than focusing on one dimension of bone or muscle mass or weakness, the concept of musculoskeletal frailty captures the overall loss of physiological reserves in the locomotor system with age. The term osteosarcopenia in particular refers to the double jeopardy of osteoporosis and sarcopenia. Muscle-bone interactions at the biomechanical, cellular, paracrine, endocrine, neuronal or nutritional level may contribute to the pathophysiology of osteosarcopenia. The paradigm wherein muscle force controls bone strength is increasingly facing competition from a model centering on the exchange of myokines, osteokines and adipokines. The most promising results have been obtained in preclinical models where common drug targets have been identified to treat these conditions simultaneously. In this narrative review, we critically summarize the current understanding of the definitions, epidemiology, pathophysiology, and treatment of osteosarcopenia as part of an integrative approach to musculoskeletal frailty.

Challenges and Future Prospects of Targeting Myostatin/Activin A Signaling to Treat Diseases of Muscle Loss and Metabolic Dysfunction

Over the past 25 years, considerable progress has been made in terms of elucidating the regulatory and signaling mechanisms underlying the control of skeletal muscle mass by myostatin and other secreted proteins belonging to the transforming growth factor-β superfamily. Preclinical studies demonstrating the potential benefits of targeting the activities of these ligands have fueled the development of numerous biologics capable of perturbing this signaling pathway and increasing muscle mass and function. These biologics have been tested in numerous clinical trials for a wide range of indications characterized by muscle loss and excess adiposity. Here, we review the results of these trials and discuss some of the challenges and future prospects for targeting this signaling pathway to treat muscle and metabolic diseases. Myostatin inhibitors may improve metabolic outcomes by increasing muscle mass, and metabolic disorders may be attractive potential indications for these molecules.

Pathogenesis, Intervention, and Current Status of Drug Development for Sarcopenia: A Review

Sarcopenia refers to the loss of muscle strength and mass in older individuals and is a major determinant of fall risk and impaired ability to perform activities of daily living, often leading to disability, loss of independence, and death. Owing to its impact on morbidity, mortality, and healthcare expenditure, sarcopenia in the elderly has become a major focus of research and public policy debates worldwide. Despite its clinical importance, sarcopenia remains under-recognized and poorly managed in routine clinical practice, partly owing to the lack of available diagnostic testing and uniform diagnostic criteria. Since the World Health Organization and the United States assigned a disease code for sarcopenia in 2016, countries worldwide have assigned their own disease codes for sarcopenia. However, there are currently no approved pharmacological agents for the treatment of sarcopenia; therefore, interventions for sarcopenia primarily focus on physical therapy for muscle strengthening and gait training as well as adequate protein intake. In this review, we aimed to examine the latest information on the epidemiology, molecular mechanisms, interventions, and possible treatments with new drugs for sarcopenia.

Cost-effectiveness analysis of sarcopenia management interventions in Iran

OBJECTIVES

Identification the optimal management intervention of sarcopenia is a concern of health systems. We aimed to analyze the cost-effectiveness of sarcopenia management strategies in Iran.

METHODS

We constructed a lifetime Markov model based on natural history. The strategies comparedincluded exercise training, nutritional supplements, whole body vibration (WBV), and various exercise interventions and nutritional supplement combinations. A total of 7 strategies was evaluated in addition to the non-intervention strategy. Parameter values were extracted from primary data and the literature, and the costs and Quality-adjusted life years (QALYs) were calculated for each strategy. Deterministic and probabilistic sensitivity analysis, including the expected value of perfect information (EVPI), was also performed to determine the robustness of the model. Analyses were performed using the 2020 version of TreeAge Pro software.

RESULTS

All seven strategies increased lifetime effectiveness (QALYs). The protein and Vitamin D₃ (P + D) strategy had the highest effectiveness values among all strategies. After removing the dominated strategies, the estimated ICER for the P + D compared to Vitamin D₃ alone (D) strategy was calculated as $131,229. Considering the cost-effectiveness threshold ($25,249), base-case results indicated that the D strategy was the most cost-effective strategy in this evaluation. Sensitivity analysis of model parameters also demonstrated the robustness of results. Also, EVPI was estimated at $273.

CONCLUSIONS

Study results, as the first economic evaluation of sarcopenia management interventions, showed that despite the higher effectiveness of D + P, the D strategy was the most cost-effective. Completing clinical evidence of various intervention options can lead to more accurate results in the future.

Efficacy of personalized exercise program on physical function in elderly patients with rheumatoid arthritis at high risk for sarcopenia: study protocol for a randomized controlled trial

BACKGROUND

Patients with rheumatoid arthritis (RA) are prone to muscle atrophy due to inflammatory cytokines and corticosteroid use and immobility due to joint pain and deformity. Although resistance training is effective and safe in reversing muscle atrophy in RA, some patients are unable to perform a conventional high-load exercise program due to disease-related limitations. This study aims to examine the efficacy of individualized exercise therapy on physical function in elderly patients with RA who are at a high risk for sarcopenia.

METHODS

This study is a single-center, parallel-group, two-arm, healthcare provider- and outcome assessor-blinded, superiority randomized controlled trial with a 1:1 allocation ratio. A total of 160 participants with RA between 60 and 85 years of age with a positive screening test for sarcopenia will be included. The intervention group will receive nutritional guidance and a four-month individualized exercise program in addition to the usual treatment. The control group will receive nutritional guidance in addition to the usual care. The primary endpoint will be physical function assessed using the Short Physical Performance Battery (SPPB) at 4 months. The data on outcome measures will be collected at baseline and at the two- and four-month follow-ups. Linear mixed-effects models for repeated measures will be conducted using the modified intention-to-treat analysis population.

DISCUSSION

This study will provide evidence on whether a personalized exercise program can improve physical function and quality of life in elderly patients with RA. Some limitations include limited generalizability due to the single-center study and lack of blinding of the patients to the intervention assignment because of the nature of the exercise. Physical therapists may use this knowledge in their daily practice to improve RA treatment. Tailored exercise may enhance the health outcomes of the RA population and contribute to a reduction in healthcare costs.

TRIAL REGISTRATION

The study protocol was retrospectively registered at the University hospital Medical Information Network-Clinical Trial Repository (UMIN-CTR) (registration number: UMIN000044930, https://www.umin.ac.jp/ctr/index-j.htm ) on January 4, 2022.

An elusive consensus definition of sarcopenia impedes research and clinical treatment: A narrative review

The definition of sarcopenia, the age-related loss of muscle mass, has evolved since the term's inception and yet there is no consensus. Many of the identified definitions of sarcopenia centre their criteria around the loss of muscle mass, loss of function, and weakness. Common variables to various definitions of sarcopenia are appendicular lean soft tissue mass (often called muscle mass), grip strength, and gait speed. However, a lack of consensus remains among operational definitions and diagnostics for this newly recognized disease and may be attributed to the absence of appropriate tools that accurately measure the outcomes of interest, such as skeletal muscle instead of lean mass. In this narrative review, we describe the evolution of the consensus groups' definition of sarcopenia, address the need for more accurate measures of muscle mass and function, and effective, low-cost treatments (i.e., resistance training and diet) for this disease. Consensus on what constitutes sarcopenia is critical to propel research in the field and, importantly, provide what prognostic value a sarcopenia diagnosis provides and how such a patient would be treated.

Rheumatoid sarcopenia: loss of skeletal muscle strength and mass in rheumatoid arthritis

Sarcopenia, a disorder that involves the generalized loss of skeletal muscle strength and mass, was formally recognized as a disease by its inclusion in the International Classification of Diseases in 2016. Sarcopenia typically affects older people, but younger individuals with chronic disease are also at risk. The risk of sarcopenia is high (with a prevalence of ≥25%) in individuals with rheumatoid arthritis (RA), and this rheumatoid sarcopenia is associated with increased likelihood of falls, fractures and physical disability, in addition to the burden of joint inflammation and damage. Chronic inflammation mediated by cytokines such as TNF, IL-6 and IFNγ contributes to aberrant muscle homeostasis (for instance, by exacerbating muscle protein breakdown), and results from transcriptomic studies have identified dysfunction of muscle stem cells and metabolism in RA. Progressive resistance exercise is an effective therapy for rheumatoid sarcopenia but it can be challenging or unsuitable for some individuals. The unmet need for anti-sarcopenia pharmacotherapies is great, both for people with RA and for otherwise healthy older adults.

Aging, Physical Exercise, Telomeres, and Sarcopenia: A Narrative Review

Human aging is a gradual and adaptive process characterized by a decrease in the homeostatic response, leading to biochemical and molecular changes that are driven by hallmarks of aging, such as oxidative stress (OxS), chronic inflammation, and telomere shortening. One of the diseases associated with the hallmarks of aging, which has a great impact on functionality and quality of life, is sarcopenia. However, the relationship between telomere length, sarcopenia, and age-related mortality has not been extensively studied. Moderate physical exercise has been shown to have a positive effect on sarcopenia, decreasing OxS and inflammation, and inducing protective effects on telomeric DNA. This results in decreased DNA strand breaks, reduced OxS and IA, and activation of repair pathways. Higher levels of physical activity are associated with an apparent increase in telomere length. This review aims to present the current state of the art of knowledge on the effect of physical exercise on telomeric maintenance and activation of repair mechanisms in sarcopenia.

Myostatin: A Skeletal Muscle Chalone

Myostatin (GDF-8) was discovered 25 years ago as a new transforming growth factor-β family member that acts as a master regulator of skeletal muscle mass. Myostatin is made by skeletal myofibers, circulates in the blood, and acts back on myofibers to limit growth. Myostatin appears to have all of the salient properties of a chalone, which is a term proposed over a half century ago to describe hypothetical circulating, tissue-specific growth inhibitors that control tissue size. The elucidation of the molecular, cellular, and physiological mechanisms underlying myostatin activity suggests that myostatin functions as a negative feedback regulator of muscle mass and raises the question as to whether this type of chalone mechanism is unique to skeletal muscle or whether it also operates in other tissues.

Pharmacokinetics and Pharmacodynamics of Bimagrumab (BYM338)

BACKGROUND

Bimagrumab is a human monoclonal antibody binding to the activin type II receptor with therapeutic potential in conditions of muscle wasting and obesity. This phase I study evaluated the pharmacokinetics (PK), pharmacodynamics (PD), and safety of various dose regimens of bimagrumab and routes of administration in healthy older adults.

METHODS

This was a randomized, double-blind, placebo-controlled, parallel-arm, multiple-dose study in older adult men and women (aged ≥ 70 years, body mass index [BMI] 18-34 kg/m²) with stable health and diet. The study comprised seven treatment groups (Cohorts 1-7). Participants received bimagrumab or placebo treatment every 4 weeks for three doses (Cohorts 1 [700 mg] and 2 [210 mg] intravenous infusion; Cohorts 3 [1500 mg] and 4 [525 mg] subcutaneous infusion), or every week for 12 doses (Cohorts 5 [300 mg], 6 [150 mg], and 7 [52.5 mg] subcutaneous bolus injection) and were followed up until week 20. Blood samples were collected for bimagrumab PK analysis. PD were assessed by dual energy X-ray absorptiometry to quantify the change from baseline in lean body mass (LBM) and fat body mass (FBM) compared with placebo. Safety was assessed throughout the study.

RESULTS

Eighty-four of 91 (92.3%) randomized participants (mean age 74.5 years; BMI 28.0 kg/m²) completed the study. Demographic characteristics were generally balanced across the groups. A target-mediated drug disposition profile was observed following both intravenous and subcutaneous administration. The absolute subcutaneous bioavailability was estimated at approximately 40%. LBM increased by 4-6% (1.5-2 kg) from baseline throughout the treatment period for intravenous and subcutaneous regimens, except for the 52.5 mg subcutaneous dose, which did not differ from placebo. Concurrently, there was a decrease in FBM (approximately 2-3 kg) for all intravenous and subcutaneous regimens. Bimagrumab was generally safe and well tolerated; adverse events were mostly mild to moderate in severity.

CONCLUSIONS

Dose levels of bimagrumab administered weekly subcutaneously resulted in PK profiles and PD effects comparable with monthly intravenous dosing, which supports the feasibility of the subcutaneous route of administration for bimagrumab for future clinical development.

The complex pathophysiology of cardiac cachexia: A review of current pathophysiology and implications for clinical practice

Cardiac cachexia is a muscle wasting process that often develops in those with chronic heart failure resulting in weight loss, low levels of physical activity, reduced quality of life, and is associated with a poor prognosis. The pathology of cardiac cachexia is complex with new evidence emerging that implicates several body systems. This review describes the pathophysiology associated with cardiac cachexia and addresses: 1) hormonal changes- neurohormonal abnormalities and metabolic hormone imbalance; 2) mechanisms of muscle wasting in cardiac cachexia, and the integral mechanisms between changed hormones due to cardiac cachexia and muscle wasting processes, and 3) associated abnormalities of gastrointestinal system that contribute to cardiac cachexia. These pleiotropic mechanisms demonstrate the intricate interplay between the affected systems and account for why cardiac cachexia is difficult to manage clinically. This review summarises current pathophysiology of cardiac cachexia and highlights symptoms of cardiac cachexia, implications for clinical practice and research gaps.

Sarcopenia definition, diagnosis and treatment: consensus is growing

Sarcopenia is a skeletal muscle disorder that commonly occurs with advancing age as well as with a number of long-term conditions. Recognition in clinical practice is relatively recent but important because of the association between sarcopenia and a range of adverse effects on health including impaired mobility, increased morbidity and mortality. Originally characterised as loss of muscle mass, the definition has evolved to focus on loss of skeletal muscle function, particularly strength, through a number of international definitions such as that of the European Working Group on Sarcopenia in Older People most recently revised in 2019. Progress in the decades ahead is likely to be seen with regard to use of routine health data, prescription of resistance exercise, translation of biology and epidemiology into first in man studies for new treatments, and focus on sarcopenia in low and middle-income countries. Immediate next steps include the newly formed Global Leadership Initiative on Sarcopenia to develop international consensus on definition and diagnosis.

Blocking ActRIIB and restoring appetite reverses cachexia and improves survival in mice with lung cancer

Cancer cachexia is a common, debilitating condition with limited therapeutic options. Using an established mouse model of lung cancer, we find that cachexia is characterized by reduced food intake, spontaneous activity, and energy expenditure accompanied by muscle metabolic dysfunction and atrophy. We identify Activin A as a purported driver of cachexia and treat with ActRIIB-Fc, a decoy ligand for TGF-β/activin family members, together with anamorelin (Ana), a ghrelin receptor agonist, to reverse muscle dysfunction and anorexia, respectively. Ana effectively increases food intake but only the combination of drugs increases lean mass, restores spontaneous activity, and improves overall survival. These beneficial effects are limited to female mice and are dependent on ovarian function. In agreement, high expression of Activin A in human lung adenocarcinoma correlates with unfavorable prognosis only in female patients, despite similar expression levels in both sexes. This study suggests that multimodal, sex-specific, therapies are needed to reverse cachexia.

Inhibition of myostatin and related signaling pathways for the treatment of muscle atrophy in motor neuron diseases

Myostatin is a negative regulator of skeletal muscle growth secreted by skeletal myocytes. In the past years, myostatin inhibition sparked interest among the scientific community for its potential to enhance muscle growth and to reduce, or even prevent, muscle atrophy. These characteristics make it a promising target for the treatment of muscle atrophy in motor neuron diseases, namely, amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), which are rare neurological diseases, whereby the degeneration of motor neurons leads to progressive muscle loss and paralysis. These diseases carry a huge burden of morbidity and mortality but, despite this unfavorable scenario, several therapeutic advancements have been made in the past years. Indeed, a number of different curative therapies for SMA have been approved, leading to a revolution in the life expectancy and outcomes of SMA patients. Similarly, tofersen, an antisense oligonucleotide, is now undergoing clinical trial phase for use in ALS patients carrying the SOD1 mutation. However, these therapies are not able to completely halt or reverse progression of muscle damage. Recently, a trial evaluating apitegromab, a myostatin inhibitor, in SMA patients was started, following positive results from preclinical studies. In this context, myostatin inhibition could represent a useful strategy to tackle motor symptoms in these patients. The aim of this review is to describe the myostatin pathway and its role in motor neuron diseases, and to summarize and critically discuss preclinical and clinical studies of myostatin inhibitors in SMA and ALS. Then, we will highlight promises and pitfalls related to the use of myostatin inhibitors in the human setting, to aid the scientific community in the development of future clinical trials.

Relationship between the serum GDF-15 concentration and muscle function in female patients receiving aortic valve replacement (TAVR, SAVR): Comparison with healthy elderly female subjects

Purpose

Methods

Results

Conclusions

Multicomponent intervention to prevent mobility disability in frail older adults: randomised controlled trial (SPRINTT project)

OBJECTIVE

To determine whether a multicomponent intervention based on physical activity with technological support and nutritional counselling prevents mobility disability in older adults with physical frailty and sarcopenia.

DESIGN

Evaluator blinded, randomised controlled trial.

SETTING

16 clinical sites across 11 European countries, January 2016 to 31 October 2019.

PARTICIPANTS

1519 community dwelling men and women aged 70 years or older with physical frailty and sarcopenia, operationalised as the co-occurrence of low functional status, defined as a short physical performance battery (SPPB) score of 3 to 9, low appendicular lean mass, and ability to independently walk 400 m. 760 participants were randomised to a multicomponent intervention and 759 received education on healthy ageing (controls).

INTERVENTIONS

The multicomponent intervention comprised moderate intensity physical activity twice weekly at a centre and up to four times weekly at home. Actimetry data were used to tailor the intervention. Participants also received personalised nutritional counselling. Control participants received education on healthy ageing once a month. Interventions and follow-up lasted for up to 36 months.

MAIN OUTCOME MEASURES

The primary outcome was mobility disability (inability to independently walk 400 m in <15 minutes). Persistent mobility disability (inability to walk 400 m on two consecutive occasions) and changes from baseline to 24 and 36 months in physical performance, muscle strength, and appendicular lean mass were analysed as pre-planned secondary outcomes. Primary comparisons were conducted in participants with baseline SPPB scores of 3-7 (n=1205). Those with SPPB scores of 8 or 9 (n=314) were analysed separately for exploratory purposes.

RESULTS

Mean age of the 1519 participants (1088 women) was 78.9 (standard deviation 5.8) years. The average follow-up was 26.4 (SD 9.5) months. Among participants with SPPB scores of 3-7, mobility disability occurred in 283/605 (46.8%) assigned to the multicomponent intervention and 316/600 (52.7%) controls (hazard ratio 0.78, 95% confidence interval 0.67 to 0.92; P=0.005). Persistent mobility disability occurred in 127/605 (21.0%) participants assigned to the multicomponent intervention and 150/600 (25.0%) controls (0.79, 0.62 to 1.01; P=0.06). The between group difference in SPPB score was 0.8 points (95% confidence interval 0.5 to 1.1 points; P<0.001) and 1.0 point (95% confidence interval 0.5 to 1.6 points; P<0.001) in favour of the multicomponent intervention at 24 and 36 months, respectively. The decline in handgrip strength at 24 months was smaller in women assigned to the multicomponent intervention than to control (0.9 kg, 95% confidence interval 0.1 to 1.6 kg; P=0.028). Women in the multicomponent intervention arm lost 0.24 kg and 0.49 kg less appendicular lean mass than controls at 24 months (95% confidence interval 0.10 to 0.39 kg; P<0.001) and 36 months (0.26 to 0.73 kg; P<0.001), respectively. Serious adverse events occurred in 237/605 (39.2%) participants assigned to the multicomponent intervention and 216/600 (36.0%) controls (risk ratio 1.09, 95% confidence interval 0.94 to 1.26). In participants with SPPB scores of 8 or 9, mobility disability occurred in 46/155 (29.7%) in the multicomponent intervention and 38/159 (23.9%) controls (hazard ratio 1.25, 95% confidence interval 0.79 to 1.95; P=0.34).

CONCLUSIONS

A multicomponent intervention was associated with a reduction in the incidence of mobility disability in older adults with physical frailty and sarcopenia and SPPB scores of 3-7. Physical frailty and sarcopenia may be targeted to preserve mobility in vulnerable older people.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02582138.

Panax ginseng and aging related disorders: A systematic review

The aging process predisposes numerous homeostatic disorders, metabolic disorders, cardiovascular diseases, neurodegenerative diseases, and cancer. Changes in diet and lifestyle and therapeutic adjuvants are essential to minimize the effects of comorbidities associated with aging. Natural products such as Panax ginseng have been used to treat and prevent diseases related to aging. This review aims to investigate the effects of Panax ginseng in various conditions associated with aging, such as inflammation, oxidative stress, mitochondrial dysfunction, apoptosis, neurodegenerative and metabolic disorders, cardiovascular diseases, and cancer. The ginsenosides, chemical constituents found in Panax ginseng, can inhibit the effects of inflammatory cytokines, inhibit signaling pathways that induce inflammation, and inhibit cells that participate in inflammatory processes. Besides, ginsenosides are involved in neuroprotective effects on the central nervous system due to anti-apoptotic, antioxidant, and anti-inflammatory effects. The use of ginseng extract showed actions on lipid homeostasis, positively regulating high-density lipoprotein, down-regulating low-density lipoprotein and triglyceride levels, and producing beneficial effects on vascular endothelial function. The use of this plant in cancer resulted in improved quality of life and mood. It decreased symptoms of fatigue, nausea, vomiting, and dyspnea, reducing anxiety. Panax ginseng has been shown to exert potent therapeutic benefits that can act as a complementary treatment in managing patients with chronic diseases related to aging.