Pathogenesis and Management of Sarcopenia

Biomedical role of L-carnitine in several organ systems, cellular tissues, and COVID-19

Carnitine is a conditionally necessary vitamin that aids in energy creation and fatty acid metabolism. Its bioavailability is higher in vegetarians than in meat-eaters. Deficits in carnitine transporters occur because of genetic mutations or in conjunction with other illnesses. Carnitine shortage can arise in health issues and diseases-including hypoglycaemia, heart disease, starvation, cirrhosis, and ageing-because of abnormalities in carnitine control. The physiologically active form of L-carnitine supports immunological function in diabetic patients. Carnitine has been demonstrated to be effective in the treatment of Alzheimer's disease, several painful neuropathies, and other conditions. It has been used as a dietary supplement for the treatment of heart disease, and it also aids in the treatment of obesity and reduces blood glucose levels. Therefore, L-carnitine shows the potential to eliminate the influences of fatigue in COVID-19, and its consumption is recommended in future clinical trials to estimate its efficacy and safety. This review focused on carnitine and its effect on tissues, covering the biosynthesis, metabolism, bioavailability, biological actions, and its effects on various body systems and COVID-19.

Two-CyDye-Based 2D-DIGE Analysis of Aged Human Muscle Biopsy Specimens

The gradual loss of skeletal muscle mass during aging and associated decline in contractile strength can result in reduced fitness, frailty, and loss of independence. In order to better understand the molecular and cellular mechanisms that underlie sarcopenia of old age and the frailty syndrome, as well as identify novel therapeutic targets to treat age-related fiber wasting, it is crucial to develop a comprehensive biomarker signature of muscle aging. Fluorescence two-dimensional gel electrophoresis (2D-DIGE) in combination with sensitive mass spectrometry presents an ideal bioanalytical tool for biomarker discovery in biogerontology. This chapter outlines the application of the 2D-DIGE method for the comparative analysis of human biopsy specimens from middle-aged versus senescent individuals using a two-CyDye-based method.

Association of Sarcopenia and Its Defining Components with the Degree of Cognitive Impairment in a Memory Clinic Population

BACKGROUND

Sarcopenia and cognitive impairment are two leading causes of disabilities.

OBJECTIVE

The objective was to examine the prevalence of sarcopenia and investigate the association between sarcopenia diagnostic components (muscle strength, muscle mass, and physical performance) and cognitive impairment in memory clinic patients.

METHODS

368 patients were included (age 59.0±7.25 years, women: 58.7%), displaying three clinical phenotypes of cognitive impairments, i.e., subjective cognitive impairment (SCI, 57%), mild cognitive impairment (MCI, 26%), and Alzheimer's disease (AD, 17%). Sarcopenia was defined according to diagnostic algorithm recommended by the European Working Group on Sarcopenia in Older People. Components of sarcopenia were grip strength, bioelectrical impedance analysis, and gait speed. They were further aggregated into a score (0-3 points) by counting the numbers of limited components. Multi-nominal logistic regression was applied.

RESULTS

Probable sarcopenia (i.e., reduced grip strength) was observed in 9.6% of the patients, and 3.5% were diagnosed with sarcopenia. Patients with faster gait speed showed less likelihood of MCI (odds ratio [OR]: 0.24, 95% confidence interval [CI]: 0.06-0.90) and AD (OR: 0.12, 95% CI: 0.03-0.60). One or more limited sarcopenia components was associated with worse cognitive function. After adjusting for potential confounders, the association remained significant only for AD (OR 4.29, 95% CI 1.45-11.92).

CONCLUSION

The results indicate a connection between the sarcopenia components and cognitive impairments. Limitations in the sarcopenia measures, especially slow walking speed, were related to poorer cognitive outcomes. More investigationsare required to further verify the causal relationship between sarcopenia and cognitive outcomes.

Bibliometric analysis of “sarcopenia” in Web of Science

Background

Sarcopenia is defined as age-related muscle wasting defined by the combination of appendicular muscle mass, muscle strength, and physical performance measures. Here, we made a bibliometric analysis of the publications published in the Web of Science (WoS) between 2018 and 2023 in terms of “sarcopenia.” In total, 12,461 articles were analyzed. The authors, publication year, title, publishing country/journal/institution, keywords, Web of Science categories, publishers, indexes, citation topics, and reports were reviewed for each article. All digital researches were done on January 03, 2023.

Results

Among 12,461 articles, according to documents types, 8855 were research articles, 1793 were reviews, 1028 were meeting abstracts, 3963 were early accesses, 364 were letters, and others (proceeding paper, correction, book chapter, etc.). A total of 7446 was open accesses.

According to the number of papers and according to publication year, 3537 were in 2021 (highest), 3349 were in 2022, 3024 were in 2020, 2532 were in 2019, and 19 were in 2023. According to the top 5 Web of Science categories list, 2792 were in Geriatrics Gerontology, 1857 were in Nutrition Dietetics, 1575 were in Medicine General Internal, 983 were in Oncology, and 914 were in Endocrinology and Metabolism. Additionally, 243 papers were in Sport Sciences, 201 were in Rehabilitation, 196 were in Rheumatology, and 187 were in Clinical Neurology.

Top citation topics were Nutrition and Dietetics (6225), Musculoskeletal Disorders (803), Bone Disease (251), Urology & Nephrology-General (236), and Hepatitis (163) (respectively). The number of citing articles, between 2019 and 2023 years, was 39,534 (with self-citations) and 39,088 (without self-citations); times cited was 94,584 (with self-citations) and 69,585 (without self-citations).

Conclusion

Our study highlights the characteristics of researches in sarcopenia and provides an objective insight into the importance of sarcopenia in elderly and patients with chronic rheumatic diseases.

Sarcopenia and Postoperative Complications, Cost of Care, and All-Cause Hospital Readmission Following Lumbar Spine Arthrodesis: A Propensity Matched Cohort Study

OBJECTIVE

Sarcopenia, characterized by decreased muscle mass and function, is projected to affect more than 200 million people worldwide by 2060. This study aimed to evaluate the rates of short-term complications following lumbar spine arthrodesis in patients with and without a recent diagnosis of sarcopenia.

METHODS

The PearlDiver database was queried to evaluate all patients who underwent index lumbar spine arthrodesis from 2012 to 2019. Multivariate logistic regression was used to compare rates of 90-day surgical and medical complications. Kaplan-Meier analysis was performed to compare cumulative rates of reoperation and all-cause hospital readmission. Two sample t testing was used to compare costs of care. Statistical significance was set at P < 0.05 a priori.

RESULTS

Of 239,953 patients undergoing lumbar spine arthrodesis, 1087 had a recent diagnosis of sarcopenia (0.45%) before surgery. Patients with sarcopenia were significantly more likely to experience a urinary tract infection (odds ratio = 1.41, P = 0.035) and undergo incision and drainage (odds ratio = 2.66, P = 0.010) within 90 days after lumbar arthrodesis. Patients with sarcopeniawere at a 24% greater risk of 1-year all-cause hospital readmission. The 90-day cost of care was significantly greater in patients with sarcopenia ($37,689.86 vs. $26,635.72; P < 0.001).

CONCLUSIONS

In patients undergoing lumbar spine arthrodesis, sarcopenia is associated with an increased risk of postoperative complications, including increased costs of care. Spine surgeons should consider screening patients for sarcopenia preoperatively and counsel them regarding their increased risk of complications. Additionally, surgeons may consider preoperative optimization, like the management of low bone density.

Dose-response relationship of resistance training for muscle morphology and strength in elderly cancer patients: A meta-analysis

Objective

To systematically evaluate the effects of resistance training (RT) on muscle strength and muscle hypertrophy in elderly cancer patients, and to provide dose-response relationships of RT variables that could improve muscle strength and morphology in elderly cancer patients.

Method

The Review Manager 5.3 was applied to analyze the 12 literatures (616 participants) through random or fixed effects model and global effect size to examine upper limb strength, lower extremity strength, and muscle hypertrophy. Sub-group analysis was made on five variables: the total number of repeated training times/week, load intensity, exercise frequency/week, exercise duration and gender. This study also examines the heterogeneity and publication bias.

Results

Twelve literatures (616 participants, 60-80 years) were included in meta-analysis. RT significantly increased the upper limb muscular strength (SMD = 0.51, 95% CI: 0.10-0.93; Z = 2.41; p = 0.02) and lower extremity strength (SMD = 0.48, 95% CI: 0.28-0.67; Z = 4.82; p < 0.00001), but had no significant effect on muscle morphology(SMD = 0.21, 95% CI: 0.01-0.42; Z = 1.88; p = 0.06). In subgroup analysis for lower extremity muscle strength in elderly male cancer patients, it was found that male intensity of 70-90%1RM, volume of 400-500 times per week, frequencies of 3 times per week, and session of 12-24 weeks, revealed the greatest effect. Funnel plot of the three studies shows that the results were reliable, and no publication bias was found.

Conclusion

RT had medium effects on improving muscle strength in elderly cancer patients, but it is not effective in improving muscle hypertrophy. In addition, when RT is performed, different training protocols can have an effect on the growth of muscle strength. Therefore, a lower extremity training protocol with a training intensity of 70-90% 1RM, a total of 400-500 repetitions per week, 3 times per week, and an exercise session of 12-24 weeks is most effective in improving lower extremity strength in elderly male cancer patients.

Beyond its Psychiatric Use: The Benefits of Low-dose Lithium Supplementation

Lithium is most well-known for its mood-stabilizing effects in the treatment of bipolar disorder. Due to its narrow therapeutic window (0.5-1.2 mM serum concentration), there is a stigma associated with lithium treatment and the adverse effects that can occur at therapeutic doses. However, several studies have indicated that doses of lithium under the predetermined therapeutic dose used in bipolar disorder treatment may have beneficial effects not only in the brain but across the body. Currently, literature shows that low-dose lithium (≤0.5 mM) may be beneficial for cardiovascular, musculoskeletal, metabolic, and cognitive function, as well as inflammatory and antioxidant processes of the aging body. There is also some evidence of low-dose lithium exerting a similar and sometimes synergistic effect on these systems. This review summarizes these findings with a focus on low-dose lithium's potential benefits on the aging process and age-related diseases of these systems, such as cardiovascular disease, osteoporosis, sarcopenia, obesity and type 2 diabetes, Alzheimer's disease, and the chronic low-grade inflammatory state known as inflammaging. Although lithium's actions have been widely studied in the brain, the study of the potential benefits of lithium, particularly at a low dose, is still relatively novel. Therefore, this review aims to provide possible mechanistic insights for future research in this field.

Motor Reaction Time, Sarcopenia and Functional Skills in Elderly Women: A Cross-Sectional Study

IMPORTANCE

Aging generates changes over the years. Because of this, the musculoskeletal system is directly degraded and suffer deficits in its performance in elderly patients with Sarcopenia, as this condition is characterized by a decrease in muscle mass and function.

OBJECTIVE

Correlate the motor reaction time and functional skills of non-sarcopenic, pre-sarcopenic and sarcopenic elderly women, and analyze influence on the risk of falls.

DESIGN

Cross-sectional observational analytical study, following the methodological strategies of STROBE (Strengthening the Reporting of Observational Studies in Epidemiology), carried out under the approval of the Research Ethics Committee of the Unievangélica University, no. 3.694.235/2019.

SETTING

Participants were evaluated regarding: cognitive status, level of physical activity, fear of falling, body composition, motor reaction time, static and dynamic balance, gait kinetics, strength and endurance of the lower limbs and finally handgrip strength.

PARTICIPANTS

A total of 59 volunteer elderly women were assessed following the diagnostic criteria for sarcopenia proposed by the European Working Group on Sarcopenia in Older People (EWGSOP).

RESULTS

The results show that there was a greater difference in motor reaction time between the non-sarcopenic and sarcopenic elderly women due to the executing organ being damaged by the presence of sarcopenia, causing motor response to slowdown. Functional deficit, fear of falling and greater risk of falls were observed in the sarcopenic group, under the harmful influence of increased motor reaction time.

CONCLUSION

Sarcopenic elderly women present increased motor reaction time, that is, slowed motor responses due to decreased muscle mass, strength and impaired musculature, which generate functional deficits that contribute to an increased risk of falls.

Prediabetes is associated with loss of appendicular skeletal muscle mass and sarcopenia

Background

Decreasing mass and metabolism in skeletal muscle are associated with increasing insulin resistance (IR) and type 2 diabetes mellitus (T2DM). The causal relation between sarcopenia and abnormal glucose metabolism may be bidirectional. This investigation is aimed to explore the detailed correlation between pre-diabetes and sarcopenia in United States (US) adults.

Methods

A total of 22,482 adults aged ≥20 years in the National Health and Nutrition Examination Survey (NHANES) were included. Generalized linear models were conducted to examine associations between diabetes status, serum glucose, glycohemoglobin (HbA1c), and sarcopenia. Generalized additive models and smooth fitting curves were used to examine the non-linear relationship between HbA1c and ASM_BMI. Sarcopenia was defined as ASM_BMI (appendicular skeletal muscle mass/body mass index) < 0.789 for males, and <0.512 for females based on the cut-off values of the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project.

Results

After fully adjusting for multiple covariates, sarcopenia was directly correlated with pre-diabetes [OR (95%CI) = 1.230 (1.057, 1.431), p = 0.008] and T2DM [OR (95%CI) = 2.106 (1.625, 2.729), p < 0.001]. In non-T2DM population, HbA1c was negatively correlated with ASM_BMI [β (95%CI) = -0.009 (-0.013, -0.005), p < 0.001]. The correlations only persisted in males. Furthermore, in male non-T2DM population, the association of HbA1c and ASM_BMI presents an inverted U-shape curve with an inflection point of HbA1c 5.2%.

Conclusion

Pre-diabetes is associated with increased risk of sarcopenia. HbA1c is an independent risk factor for loss of appendicular skeletal muscle mass and sarcopenia when HbA1c greater than 5.2% in the male non-T2DM population.

Low preoperative skeletal muscle index increases the risk of mortality among resectable pancreatic cancer patients: A retrospective study

BACKGROUND

The only potential curative treatment for patients with pancreatic cancer is surgery; however, the prognosis remains poor. Measures of body composition based on computed tomography (CT) have been established as a reliable predictor of the prognosis of cancer patients after surgery.

AIM

To elucidate the associations of body composition measures derived from preoperative CT scans with the prognosis of patients with pancreatic cancer.

METHODS

One hundred fifteen patients undergoing pancreatic resection with curative intent for pancreatic cancer were retrospectively enrolled. A preoperative CT scan at the third lumbar vertebral level was performed to measure the skeletal muscle index (SMI), mean skeletal muscle radiodensity, subcutaneous adipose tissue index, and visceral to subcutaneous adipose tissue area ratio. The clinical and pathological data were collected. The effects of these factors on long-term survival were evaluated.

RESULTS

Among the five body composition measures, only low SMI independently predicted overall survival (OS) [hazard ratio (HR): 2.307; 95% confidence interval (CI): 1.210-4.402] and recurrence-free survival (HR: 1.907; 95%CI: 1.147-3.171). Furthermore, patients with low SMI (vs high SMI) were older (68.8 ± 9.3 years vs 63.3 ± 8.4 years); low SMI was present in 27 of 56 patients (48.2%) aged 65 years and older and in 11 of 59 younger patients (18.6%). In addition, subgroup analyses revealed that the correlation between low SMI and OS was observed only in patients aged 65 years and older.

CONCLUSION

Low preoperative SMI was more prevalent in elderly patients and was associated with a poor prognosis among pancreatic cancer patients, especially elderly patients.

Prediction of 30-Day Readmission in Hospitalized Older Adults Using Comprehensive Geriatric Assessment and LACE Index and HOSPITAL Score

(1) Background: Elders have higher rates of rehospitalization, especially those with functional decline. We aimed to investigate potential predictors of 30-day readmission risk by comprehensive geriatric assessment (CGA) in hospitalized patients aged 65 years or older and to examine the predictive ability of the LACE index and HOSPITAL score in older patients with a combination of malnutrition and physical dysfunction. (2) Methods: We included patients admitted to a geriatric ward in a tertiary hospital from July 2012 to August 2018. CGA components including cognitive, functional, nutritional, and social parameters were assessed at admission and recorded, as well as clinical information. The association factors with 30-day hospital readmission were analyzed by multivariate logistic regression analysis. The predictive ability of the LACE and HOSPITAL score was assessed using receiver operator characteristic curve analysis. (3) Results: During the study period, 1509 patients admitted to a ward were recorded. Of these patients, 233 (15.4%) were readmitted within 30 days. Those who were readmitted presented with higher comorbidity numbers and poorer performance of CGA, including gait ability, activities of daily living (ADL), and nutritional status. Multivariate regression analysis showed that male gender and moderately impaired gait ability were independently correlated with 30-day hospital readmissions, while other components such as functional impairment (as ADL) and nutritional status were not associated with 30-day rehospitalization. The receiver operating characteristics for the LACE index and HOSPITAL score showed that both predicting scores performed poorly at predicting 30-day hospital readmission (C-statistic = 0.59) and did not perform better in any of the subgroups. (4) Conclusions: Our study showed that only some components of CGA, mobile disability, and gender were independently associated with increased risk of readmission. However, the LACE index and HOSPITAL score had a poor discriminating ability for predicting 30-day hospitalization in all and subgroup patients. Further identifiers are required to better estimate the 30-day readmission rates in this patient population.

Nutritional Status and Sarcopenia in Nursing Home Residents: A Cross-Sectional Study

OBJECTIVE

This study aimed to assess the nutritional status and sarcopenia in older people living in nursing homes.

METHODS

This cross-sectional study enrolled 386 older adults in nursing homes in Hunan Province, China. Assessments included the Mini Nutritional Assessment Short Form for nutrition risk, Dietary Diversity Score for dietary diversity and Mini Mental State Examination for cognitive status. Sociodemographic (e.g., age, sex and educational level), health-related characteristics (e.g., food intake, self-care status and medication), body composition (e.g., body mass index [BMI], protein, body fat mass [BFM], percent body fat [PBF], skeletal muscle index [SMI] and total body water [TBW]) and anthropometric parameters data (e.g., calf circumference [CC], upper arm circumference [UAC], handgrip and gait speed) were also collected. Malnutrition and their associated risk were analyzed by multivariable Poisson regression analysis.

RESULTS

In total, 32.4% of participants (n = 125) were at risk of malnutrition and 49.7% (n = 192) suffered from sarcopenia. Nutritional status was positively associated with age (risk ratio [RR] = 1.03), sarcopenia (RR = 1.88), tooth loss affecting food intake (RR = 1.45), low self-care status (RR = 1.82) and moderate/inadequate dietary diversity (RR = 2.04) and negatively associated with one child (RR = 0.27), BMI (RR = 0.82), protein (RR = 0.76), BFM (RR = 0.91), PBF (RR = 0.94), SMI (RR = 0.65), TBW (RR = 0.94), CC (RR = 0.89) and UAC (RR = 0.86).

CONCLUSIONS

Age, number of children, sarcopenia, food intake, self-care status, dietary diversity and body composition were associated with malnutrition among nursing home residents. For vulnerable groups, researchers should focus on raising the body composition indicators, such as BMI, protein, BFM, SMI and TBW and measuring CC and UAC for initial screening.

Associations between Body Mass Index, Waist Circumference, and Myocardial Infarction in Older Adults Aged over 75 Years: A Population-Based Cohort Study

Background and Objectives: Body mass index (BMI) is widely used as a standard screening method for obesity and an indicator of related diseases. However, its inability to distinguish between lean body mass and body fat limits its utility. This limitation may be more prominent in older populations, wherein age-related sarcopenia and increased visceral fat due to the redistribution of adipose tissue may preclude a precise estimation of obesity. Many studies suggest that waist circumference (WC) is more strongly related to obesity-related diseases. There are also different opinions on whether the obesity paradox is real or a result of confusing interpretations. This study seeks to determine the association between myocardial infarction (MI), BMI, and WC in older adults and to determine if BMI and WC can reliably predict the risk of cardiovascular disease. Materials and Methods: We conducted a cohort study of older Korean adults aged over 75 years registered in the National Health Insurance System Senior database. Results: The results from the analysis using model 5, which was adjusted for each study variable, showed that the lower the BMI, the higher the hazard ratio (HR) of MI and vice versa. On the other hand, groups with lower than normal WC showed lower HR; even if it was higher, the difference was not statistically significant. Those with abdominal obesity tended to have an increased HR of MI. Conclusions: This study found that HR for MI has a negative relationship with BMI, whereas it has a positive relationship with WC. Furthermore, WC is a more appropriate indicator for predicting the risk of MI in the older population.

Acupunch Exercise Improved Muscle Mass, Hand Grip Strength, and Sleep Quality of Institutional Older Adults with Probable Sarcopenia

This study tested the effectiveness of a 6-month vitality acupunch (VA) exercise program on muscle mass, hand grip strength, and sleep quality in institutional older adults with probable sarcopenia. A cluster randomized controlled trial was conducted. A total of 103 older adults were assigned to the experimental group ( n = 52) and control group ( n = 51) according to the institution they inhabited. After the 6-month VA exercise intervention, the experimental group showed significant increases in muscle mass ( F = 5.93, p = .017), hand grip strength ( F = 56.73, p < .001), and improved sleep quality ( F = 23.20, p < .001) compared to the control group. Based on the meridian theory that promotes qi and blood circulation, VA exercise has positive effects on muscle mass, hand grip strength, and sleep quality in older adults with probable sarcopenia.

Muscle Delivery of Mitochondria-Targeted Drugs for the Treatment of Sarcopenia: Rationale and Perspectives

An impairment in mitochondrial homeostasis plays a crucial role in the process of aging and contributes to the incidence of age-related diseases, including sarcopenia, which is defined as an age-dependent loss of muscle mass and strength. Mitochondrial dysfunction exerts a negative impact on several cellular activities, including bioenergetics, metabolism, and apoptosis. In sarcopenia, mitochondria homeostasis is disrupted because of reduced oxidative phosphorylation and ATP generation, the enhanced production of reactive species, and impaired antioxidant defense. This review re-establishes the most recent evidence on mitochondrial defects that are thought to be relevant in the pathogenesis of sarcopenia and that may represent promising therapeutic targets for its prevention/treatment. Furthermore, we describe mechanisms of action and translational potential of promising mitochondria-targeted drug delivery systems, including molecules able to boost the metabolism and bioenergetics, counteract apoptosis, antioxidants to scavenge reactive species and decrease oxidative stress, and target mitophagy. Even though these mitochondria-delivered strategies demonstrate to be promising in preclinical models, their use needs to be promoted for clinical studies. Therefore, there is a compelling demand to further understand the mechanisms modulating mitochondrial homeostasis, to characterize powerful compounds that target muscle mitochondria to prevent sarcopenia in aged people.

Ginsenoside Rb1 Prevents Oxidative Stress-Induced Apoptosis and Mitochondrial Dysfunction in Muscle Stem Cells via NF-κB Pathway

Sarcopenia, featured by the progressive loss of skeletal muscle function and mass, is associated with the impaired function of muscle stem cells (MuSCs) caused by increasing oxidative stress in senescent skeletal muscle tissue during aging. Intact function of MuSCs maintains the regenerative potential as well as the homeostasis of skeletal muscle tissues during aging. Ginsenoside Rb1, a natural compound from ginseng, exhibited the effects of antioxidation and against apoptosis. However, its effects of restoring MuSC function during aging and improving age-related sarcopenia remained unknown. In this study, we investigated the role of Rb1 in improving MuSC function and inhibiting apoptosis by reducing oxidative stress levels. We found that Rb1 inhibited the accumulation of reactive oxygen species (ROS) and protected the cells from oxidative stress to attenuate the H₂O₂-induced cytotoxicity. Rb1 also blocked oxidative stress-induced apoptosis by inhibiting the activation of caspase-3/9, which antagonized the decrease in mitochondrial content and the increase in mitochondrial abnormalities caused by oxidative stress via promoting the protein expression of genes involved in mitochondrial biogenesis. Mechanistically, it was proven that Rb1 exerted its antioxidant effects and avoided the apoptosis of myoblasts by targeting the core regulator of the nuclear factor-kappa B (NF-κB) signal pathway. Therefore, these findings suggest that Rb1 may have a beneficial role in the prevention and treatment of MuSC exhaustion-related diseases like sarcopenia.

Amino Acids in Cancer and Cachexia: An Integrated View

Rapid tumor growth requires elevated biosynthetic activity, supported by metabolic rewiring occurring both intrinsically in cancer cells and extrinsically in the cancer host. The Warburg effect is one such example, burning glucose to produce a continuous flux of biomass substrates in cancer cells at the cost of energy wasting metabolic cycles in the host to maintain stable glycemia. Amino acid (AA) metabolism is profoundly altered in cancer cells, which use AAs for energy production and for supporting cell proliferation. The peculiarities in cancer AA metabolism allow the identification of specific vulnerabilities as targets of anti-cancer treatments. In the current review, specific approaches targeting AAs in terms of either deprivation or supplementation are discussed. Although based on opposed strategies, both show, in vitro and in vivo, positive effects. Any AA-targeted intervention will inevitably impact the cancer host, who frequently already has cachexia. Cancer cachexia is a wasting syndrome, also due to malnutrition, that compromises the effectiveness of anti-cancer drugs and eventually causes the patient's death. AA deprivation may exacerbate malnutrition and cachexia, while AA supplementation may improve the nutritional status, counteract cachexia, and predispose the patient to a more effective anti-cancer treatment. Here is provided an attempt to describe the AA-based therapeutic approaches that integrate currently distant points of view on cancer-centered and host-centered research, providing a glimpse of several potential investigations that approach cachexia as a unique cancer disease.

Frailty, sarcopenia and diabetic kidney disease: where do we stand?

The aim of this narrative non-systematic review was to investigate the potential interplay among frailty syndrome, sarcopenia and diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM) patients. Data derived from a limited number of studies underline that DKD is a significant risk factor for frailty. On the other hand, frailty syndrome poses a higher risk for end-stage renal disease (ESRD) in subjects with DKD. In addition, frailty seems to affect the cognitive function and social life of DKD individuals, whilst as DKD deteriorates, there is a higher prevalence of sarcopenia which is a fundamental frailty factor. As a result, it is shown that a bidirectional relation is established between these entities, as diabetes mellitus (DM) affects the components of frailty and sarcopenia and vice versa. This vicious cycle is created through multiple pathophysiologic mechanisms, including the anabolic role of insulin, low-grade inflammation, cytokines and endothelial function, prompting further investigation in this area. Specific nutritional and exercise interventions are imperative to be established in order to ameliorate potential adverse outcomes, concerning these entities.

Maria MT, Hori S, Morikawa M, Marito P, Kaneko N, Nohno K, Nose H, Masuki S, Ono T. Effects of Interval Walking Training on Oral Health Status in Middle-Aged and Older Adults: A Case-Control Study

The purpose of this study was to determine the effect of walking training "Interval Walking Training (IWT)" on oral health status. Participants were divided into two groups: an exercise intervention group and a non-intervention group (control). The intervention group consisted of 59 subjects (20 males, 39 females) aged 50 years or older who participated in the IWT program in Matsumoto from 2019 to April 2022. The control group consisted of 33 subjects (14 males and 19 females) aged 50 years or older who have visited Niigata University Medical and Dental Hospital and agreed to participate in the study. The intervention group underwent walking training (interval walking training) for at least 5-6 months. The walking training consisted of five sets of fast walking above 70% peak aerobic capacity for walking (VO₂peak) for 3 min, followed by 3 min of slow walking at ~40% VO₂ peak per day for more than four days/week. The oral health status was evaluated for the number of teeth, occlusal force, salivary occult blood, masticatory performance, and tongue pressure. A total of 57 participants were analyzed in the intervention group (18 males and 39 females, age: 66.7 ± 0.8 (mean ± S.E.) years) and 33 participants in the control group (14 males and 19 females, age: 74.5 ± 1.1 (mean ± S.E.) years). There were no significant differences in gender, salivary occult blood, tongue pressure, masticatory performance, or occlusal force between the two groups at the start of the intervention (p = 0.36, p = 0.48, p = 0.42, p = 0.58, and p = 0.08, respectively by unpaired t-test or χ² test). On the other hand, there were significant differences in age and BMI, with a trend toward lower age and higher BMI in the intervention group (p < 0.001 and p < 0.001, respectively, by unpaired t-test). In terms of rate of change, the intervention group showed a significant increase in occlusal force (F = 4.5, p = 0.04, ANCOVA) and a significant decrease in BMI (F = 7.3, p = 0.009, ANCOVA). No significant differences were observed in the other measured items. It was found that walking training in both middle-aged and older people does not only affect the physical aspect of weight loss but may help maintain and improve the occlusal force.

Osteosarcopenia in Patients with Chronic Obstructive Pulmonary Diseases: Which Pathophysiologic Implications for Rehabilitation?

Chronic obstructive pulmonary disease (COPD) is a burdensome condition affecting a growing number of people worldwide, frequently related to major comorbidities and functional impairment. In these patients, several factors might have a role in promoting both bone and muscle loss, including systemic inflammation, corticosteroid therapies, sedentary behaviours, deconditioning, malnutrition, smoking habits, and alcohol consumption. On the other hand, bone and muscle tissues share several linkages from functional, embryological, and biochemical points of view. Osteosarcopenia has been recently defined by the coexistence of osteoporosis and sarcopenia, but the precise mechanisms underpinning osteosarcopenia in patients with COPD are still unknown. In this scenario, a deeper understanding of the molecular basis of osteosarcopenia might guide clinicians in a personalized approach integrating skeletal muscle health with the pulmonary rehabilitation framework in COPD. Taken together, our results summarized the currently available evidence about the multilevel interactions between osteosarcopenia and COPD to pave the way for a comprehensive approach targeting the most common risk factors of these pathological conditions. Further studies are needed to clarify the role of modern clinical strategies and telemedicine solutions to optimize healthcare delivery in patients with COPD, including osteopenia, osteoporosis, and sarcopenia screening in these subjects.

Is ambient air pollution associated with sarcopenia? Results from a nation-wide cross-sectional study

BACKGROUND

sarcopenia is a disease that involves the degeneration of muscle strength, muscle mass and physical performance. It remains unknown whether air pollution exposure increases the risk of sarcopenia.

METHODS

the baseline survey of the UK Biobank was used in this study. Sarcopenia was identified according to European Working Group on Sarcopenia in Older People 2 (EWGSOP2) and classified into non-sarcopenia and probable sarcopenia. Land use regressions were used to estimate concentrations of particulate matter (PM2.5), coarse particles (PMcoarse), PM10, PM2.5 absorbance, nitrogen dioxide (NO2) and nitrogen oxides (NOx). Logistic regression models were applied to estimate the associations between air pollution and sarcopenia and its components.

RESULTS

out of 352,265 participants, 28,710 (8.2%) were identified with probable sarcopenia. In adjusted models, there were increased odds of probable sarcopenia for each interquartile range increase in PM2.5 (OR: 1.06; 95% CI: 1.04, 1.07), PM10 (OR: 1.15; 95% CI: 1.13, 1.17), PMcoarse (OR: 1.02; 95% CI:1.01, 1.03), PM2.5 absorbance (OR: 1.08; 95% CI: 1.07, 1.10), NO2 (OR: 1.12; 95% CI:1.10, 1.14) and NOx (OR: 1.06; 95% CI: 1.05, 1.08).

CONCLUSIONS

this study suggests that exposure to ambient air pollution might be one risk factor of sarcopenia. Prospective studies are needed to further confirm our findings.

Preoperative Considerations for the Frail Patient

Frailty is a common geriatric syndrome, the relevance of which is becoming increasingly apparent in the clinical setting. It is often accompanied by varying degrees of sarcopenia and/or osteoporosis, leading to a decline in physical function, decreased levels of physical activity, and overall poorer health outcomes in older adults. Identifying this cohort of patients before stressor events such as spinal surgery can prove paramount to improving the postoperative outcomes of these patients. This review provides a pertinent descriptive analysis to aid identification of frailty in a clinical setting, in addition to outlining methods of preoperative intervention that may improve postoperative outcomes.

Gut microbiota as a promising therapeutic target for age-related sarcopenia

Sarcopenia is characterized by a progressive loss of skeletal muscle mass and function with aging. Recently, sarcopenia has been shown to be closely related with gut microbiota. Strategies such as probiotics and fecal microbiota transplantation have shown potential to ameliorate the muscle loss. This review will focus on the age-related sarcopenia, in particular on the relationship between gut microbiota and age-related sarcopenia, how gut microbiota is engaged in sarcopenia, and the potential role of gut microbiota in the treatment of age-related sarcopenia.

Effectiveness of a Novel Food Composed of Leucine, Omega-3 Fatty Acids and Probiotic Lactobacillus paracasei PS23 for the Treatment of Sarcopenia in Elderly Subjects: A 2-Month Randomized Double-Blind Placebo-Controlled Trial

Sarcopenia is a complex process characterized by a progressive decrease in muscle mass and strength. Various nutrients have been shown to be effective in supporting muscular performance. This randomized clinical trial aimed to evaluate the effectiveness of a 2-month administration of food for special medical purposes composed of omega-3 fatty acids (500 mg), leucine (2.5 g), and probiotic Lactobacillus paracasei PS23 (LPPS23), on appendicular lean mass (ALM), muscle performance, inflammatory status, and amino acid profile in sarcopenic patients. A total of 60 participants (aged 79.7 ± 4.8 years and a body mass index of 22.2 ± 2.1 kg/m2) were enrolled and randomly assigned to either intervention (n = 22) or placebo group (n = 28). Comparing the differences in effects between groups (intervention minus placebo effects), ALM increased significantly in the intervention group (p < 0.05), with no discernible change in the placebo group. Similarly, significant differences were also observed for the Tinetti scale (+2.39 points, p < 0.05), the SPPB total score (+2.22 points, p < 0.05), and the handgrip strength (4.09 kg, p < 0.05). Visceral adipose tissue significantly decreased in the intervention group compared to the placebo group at 60 days −0.69 g (95% CI: −1.09, 0.29) vs. 0.27 g (95% CI: −0.11, 0.65), groups difference −0.96 (95% CI: −1.52, 0.39, p = 0.001). A statistically significant increase in levels of valine, leucine, isoleucine, and total amino acid profiles was observed in the intervention group compared with the placebo group at 60 days (p = 0.001). When taken together, these beneficial effects may be attributed to the innovative composition of this special medical-purpose food which could be considered for the treatment of sarcopenia in the elderly.

Improving the prognosis before and after liver transplantation: Is muscle a game changer?

Liver transplantation (LT) is currently the only curative treatment option for selected patients with end stage liver disease or hepatocellular carcinoma. Improving waiting list-mortality, post-transplant morbidity and mortality and refining the selection of the patients remain our current central objectives. In this field, different concepts dealing with nutrition and the muscle such as sarcopenia, malnutrition, frailty or myosteatosis have emerged as possible game changers. For more than a decade, many prospective studies have demonstrated that sarcopenia and frailty are major predictive factors of mortality in the waiting list but also after LT. Malnutrition is also a well-known risk factor for morbidity and mor-tality. Muscle composition is a newer concept giving insight on muscle quality which has also been shown to be linked to poorer outcomes. Each of these terms has a precise definition as well as pathophysiological mechanisms. The bi-directional liver-muscle axis makes sense in this situation. Defining the best, easy to use in clinical practice tools to assess muscle quality, quantity, and function in this specific population and developing quality prospective studies to identify interventional strategies that could improve these parameters as well as evaluate the effect on mortality are among the important challenges of today.

Impact of sarcopenia in bladder preservation therapy for muscle-invasive bladder cancer patients: a narrative review

BACKGROUND AND OBJECTIVE

Muscle-invasive bladder cancer (MIBC) is a biologically aggressive disease and its prognosis is poor. Radical cystectomy (RC) with urinary diversion and lymph node dissection is the gold standard treatment for MIBC patients. Accumulating evidence indicates that sarcopenia, the degenerative and systemic loss of skeletal muscle mass, is a significant predictor of higher rates of mortality and perioperative complications following RC. Recently, bladder preservation therapy has been offered as an alternative in appropriately selected MIBC patients who desire to preserve their bladders and those unfit or unwilling for RC. Here, we performed a narrative review on the impact of sarcopenia on oncological outcomes and complication rates in MIBC patients treated with bladder preservation therapy.

METHODS

A literature review was performed using the PubMed and Scopus databases.

KEY CONTENT AND FINDINGS

We identified two studies reported the impact of sarcopenia on responses to trimodal therapy and survival outcomes in MIBC patients. Consolidative partial cystectomy was performed in patients who achieved clinical complete response (CR) to trimodal therapy in one of the two studies. In both studies, CR rates to trimodal therapy are comparable between sarcopenic and non-sarcopenic patients. Sarcopenia was not significantly associated with shorter survival after completing bladder preservation therapy in either study. For complication rates of bladder preservation therapy, one study showed equivalent complication rates of consolidative partial cystectomy between sarcopenic and non-sarcopenic patients. In addition, in another small series of trimodal therapy, sarcopenic patients showed a higher rate of complications of trimodal therapy compared with non-sarcopenic patients.

CONCLUSIONS

According to the result of our literature review, sarcopenia would not affect responses to trimodal therapy and prognosis in MIBC patients treated with bladder preservation therapy. Although the effect of sarcopenia on complication rates of bladder preservation therapy is inconclusive due to limited evidence, bladder preservation therapy could be a viable alternative option in carefully selected MIBC patients regardless of the presence of sarcopenia.

Influence of temporal muscle thickness on the outcome of radiosurgically treated patients with brain metastases from non-small cell lung cancer

OBJECTIVE

The purpose of this study was to assess the impact of temporal muscle thickness (TMT), a surrogate marker for sarcopenia, in radiosurgically treated patients with brain metastases (BMs) from non-small cell lung cancer (NSCLC).

METHODS

For 566 patients with BMs from NSCLC in the period between June 2012 and December 2019, TMT values were retrospectively measured on the planning brain magnetic resonance imaging (MRI) studies that had been obtained before their first Gamma Knife radiosurgery treatment (GKRS1). Predefined sex-specific TMT cutoff values were used to stratify the study cohort into patients at risk for sarcopenia and patients with normal muscle status. Cox regression models adjusted for other prognostic parameters were used to evaluate sarcopenia as an independent prognostic factor.

RESULTS

In sarcopenia patients with a TMT below the sex-specific cutoff values, the risk of death was significantly increased (HR 1.908, 95% CI 1.550-2.349, p < 0.001). In addition, sarcopenia was revealed as an independent prognostic factor even after adjusting for age groups, sex, number of BMs, presence of extracranial metastases, NSCLC subtypes, Karnofsky Performance Status groups, recursive partitioning analysis classes, and concomitant immunotherapy or targeted therapy (HR 1.680, 95% CI 1.347-2.095, p < 0.001). However, patients at risk for sarcopenia showed no significant differences in the estimated mean time until local BM progression after GKRS1, compared to patients with normal muscle status (p = 0.639).

CONCLUSIONS

TMT obtained from planning MRI studies is an independent prognostic marker in radiosurgically treated patients with BMs from NSCLC and may aid patient stratification in future clinical trials.

Do body composition parameters correlate with response to targeted therapy in ER+/HER2- metastatic breast cancer patients? Role of sarcopenia and obesity

Purpose

To investigate the association between body composition parameters, sarcopenia, obesity and prognosis in patients with metastatic ER+/HER2- breast cancer under therapy with cyclin-dependent kinase (CDK) 4/6 inhibitors.

Methods

92 patients with biopsy-proven metastatic ER+/HER2- breast cancer, treated with CDK 4/6 inhibitors between 2018 and 2021 at our center, were included in this retrospective analysis. Visceral Adipose Tissue (VAT), Subcutaneous Adipose Tissue (SAT) and Skeletal Muscle Index (SMI) were measured before starting therapy with CDK 4/6 inhibitors (Palbociclib, Abemaciclib or Ribociclib). Measurements were performed on a computed tomography-derived abdominal image at third lumbar vertebra (L3) level by an automatic dedicated software (Quantib body composition^®, Rotterdam, Netherlands). Visceral obesity was defined as a VAT area > 130 cm². Sarcopenia was defined as SMI < 40 cm²/m². Changes in breast lesion size were evaluated after 6 months of treatment. Response to therapy was assessed according to RECIST 1.1 criteria. Spearman’s correlation and χ² analyses were performed.

Results

Out of 92 patients, 30 were included in the evaluation. Of the 30 patients (mean age 53 ± 12 years), 7 patients were sarcopenic, 16 were obese, while 7 patients were neither sarcopenic nor obese. Statistical analyses showed that good response to therapy was correlated to higher SMI values (p < 0.001), higher VAT values (p = 0.008) and obesity (p = 0.007); poor response to therapy was correlated to sarcopenia (p < 0.001). Moreover, there was a significant association between sarcopenia and menopause (p = 0.021) and between sarcopenia and the persistence of axillary lymphadenopathies after treatment (p = 0.003), while the disappearance of axillary lymphadenopathies was associated with obesity (p = 0.028).

Conclusions

There is a growing interest in body composition, especially in the field of breast cancer. Our results showed an interesting correlation between sarcopenia and progression of disease, and demonstrated that VAT can positively influence the response to targeted therapy with CDK 4/6 inhibitors. Larger-scale studies are needed to confirm these preliminary results.

Clinical Relevance

Sarcopenia and obesity seem to predict negative outcomes in many oncologic entities. Their prevalence and impact in current breast cancer care are promising but still controversial.

Bronchial Asthma and Sarcopenia: An Upcoming Potential Interaction

BACKGROUND

Sarcopenia seems to be an emerging health issue worldwide, concerning the progressive loss of skeletal muscle mass, accompanied by adverse outcomes. Asthma is a chronic inflammatory respiratory condition that is widespread in the world, affecting approximately 8% of adults. Although data are scarce, we aim to shed light on the potential association between low muscle mass and asthma and point out any probable negative feedback on each other.

METHODS

We searched within the PubMed, Scopus, MEDLINE, and Google Scholar databases.

STUDY SELECTIONS

Three studies were included in our analysis. Only original studies written in English were included, while the references of the research articles were thoroughly examined for more relevant studies. Moreover, animal model studies were excluded.

RESULTS

2% to 17% of asthmatics had sarcopenia according to the existent literature. Sarcopenic asthmatic patients seem to have reduced lung function, while their mortality risk may be increased. Furthermore, patients with asthma- chronic obstructive pulmonary disease (COPD) overlap syndrome phenotype and sarcopenia might have a higher risk of osteopenia and osteoporosis progression, leading consequently to an increased risk of fractures and disability.

CONCLUSIONS

Emerging data support that pulmonologists should be aware of the sarcopenia concept and be prepared to evaluate the existence of low muscle mass in their asthmatic patients.

Extra Virgin Olive Oil (EVOO), a Mediterranean Diet Component, in the Management of Muscle Mass and Function Preservation

Aging results in a progressive decline in skeletal muscle mass, strength and function, a condition known as sarcopenia. This pathological condition is due to multifactorial processes including physical inactivity, inflammation, oxidative stress, hormonal changes, and nutritional intake. Physical therapy remains the standard approach to treat sarcopenia, although some interventions based on dietary supplementation are in clinical development. In this context, thanks to its known anti-inflammatory and antioxidative properties, there is great interest in using extra virgin olive oil (EVOO) supplementation to promote muscle mass and health in sarcopenic patients. To date, the molecular mechanisms responsible for the pathological changes associated with sarcopenia remain undefined; however, a complete understanding of the signaling pathways that regulate skeletal muscle protein synthesis and their behavior during sarcopenia appears vital for defining how EVOO might attenuate muscle wasting during aging. This review highlights the main molecular players that control skeletal muscle mass, with particular regard to sarcopenia, and discusses, based on the more recent findings, the potential of EVOO in delaying/preventing loss of muscle mass and function, with the aim of stimulating further research to assess dietary supplementation with EVOO as an approach to prevent or delay sarcopenia in aging individuals.

The effects of synbiotic and/or vitamin D supplementation on gut-muscle axis in overweight and obese women: a study protocol for a double-blind, randomized, placebo-controlled trial

BACKGROUND

Sarcopenia refers to an age-related loss of skeletal muscle content, strength, and function, leading to a decrease in mobility. Obesity may exacerbate age-related complications such as sarcopenia through inflammatory pathways. In addition, intestinal dysbiosis has been proposed as an emerging contributor to sarcopenia due to the stimulation of the immune system and elevated barrier permeability of the intestine. Targeting microbiome with synbiotic and vitamin D supplementation may modulate the microbiome followed by the enhancement of sarcopenia indices. Thus, the present study aims to evaluate the effect of synbiotic supplementation with or without vitamin D on the intestinal microbiome and its relationship with strength, muscle function, and body composition in middle-aged overweight and obese women.

METHODS

This multi-factorial, double-blind, randomized controlled trial will be conducted on 88 participants in eight weeks. The participants will be allocated into four groups receiving vitamin D placebo (weekly) and synbiotic placebo (daily), vitamin D and synbiotic placebo, vitamin D placebo and symbiotic, and vitamin D and synbiotic. Intestinal microbiome assessment will be done by DNA isolation and real-time polymerase chain reaction (PCR). In addition, anthropometric indices, body composition, muscle strength, and physical performance will be evaluated by standard methods. All measurements will be made at the beginning and end of the study.

DISCUSSION

The previous studies showed that probiotics were involved in reducing inflammation, insulin sensitivity, modulation of atrophy markers such as atherogen-1, and decreasing reactive oxygen indices. In addition, vitamin D was found to improve the intestinal microbiome and facilitate muscle anabolism. The present protocol is novel as it aims to investigate the impact of the co-supplementation of synbiotic and vitamin D on the gut microbiome and sarcopenia indices.

TRIAL REGISTRATION

This trial has been registered in the Iranian Registry of Clinical Trials (IRCT20090822002365N25, date of registration: March 2021).

Independent and joint associations of skeletal muscle mass and physical performance with all-cause mortality among older adults: a 12-year prospective cohort study

Background

Decreased skeletal muscle mass and low physical performance are independently associated with increased mortality in elderly individuals. However, little is known about the effects of skeletal muscle mass combined with physical performance on the prediction of mortality risk among community-dwelling older adults. This study aimed to determine the combined effects of skeletal muscle mass and physical performance on total mortality.

Methods

A community-based prospective cohort study was conducted among 641 participants aged 65 and older in 2009. The height-adjusted skeletal muscle index (hSMI) and the weight-adjusted SMI (wSMI) were determined by dual-energy X-ray absorptiometry examination. Physical performance tests measured at baseline included gait speed (GS), timed up-and-go (TUG) test, timed chair stand (TCS), weight-adjusted leg press (WaLP), and handgrip strength (HS). Cox proportional hazards regression models were applied to determine the adjusted hazard ratios (HRs) of mortality with 95% confidence intervals (95% CIs) for baseline skeletal muscle mass, physical performance, and traditional risk factors.

Results

During the follow-up of 12 years, 198 (30.89%) participants died. Low hSMI, low GS, high TUG, high TCS, low WaLP, and low HS were associated with high risks of mortality after the adjustment for confounders. The results of receiver operating characteristic (ROC) curve analyses revealed the values of ROC for models with additional consideration for TUG or all indicators significantly improved the discriminatory ability of mortality compared with the model with traditional factors (all P < 0.05). Elders with low hSMI and low GS (HRs = 4.33, 95% CI: 2.76–6.78), high TUG (4.11, 2.60–6.48), high TCS (2.97, 1.92–4.59), low WaLP (3.19, 2.13–4.79), and low HS (4.08, 2.70–6.17) were associated with high risks of mortality compared with those with high hSMI and their corresponding counterparts.

Conclusion

The hSMI and physical performance are significantly associated with increased risks of all-cause mortality. The combined use of hSMI and physical performance can provide improved risk stratification, which may be appropriately used as a screening tool targeting high-risk elders for the effective prevention of sarcopenia-related mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03292-0.

Management of Type 2 Diabetes Mellitus in Elderly Patients with Frailty and/or Sarcopenia

The life expectancy of the population is increasing worldwide due to improvements in the prevention, diagnosis, and treatment of diseases. This favors a higher prevalence of type 2 diabetes mellitus (T2DM) in the elderly. Sarcopenia and frailty are also frequently present in aging. These three entities share common mechanisms such as insulin resistance, chronic inflammation, and mitochondrial dysfunction. The coexistence of these situations worsens the prognosis of elderly patients. In this paper, we review the main measures for the prevention and management of sarcopenia and/or frailty in elderly patients with T2DM.

A Preclinical Systematic Review of the Effects of Chronic Exercise on Autophagy-Related Proteins in Aging Skeletal Muscle

Background: Exercise is one of the most effective interventions for preventing and treating skeletal muscle aging. Exercise-induced autophagy is widely acknowledged to regulate skeletal muscle mass and delay skeletal muscle aging. However, the mechanisms underlying of the effect of different exercises on autophagy in aging skeletal muscle remain unclear.

Methods: A systematic review was performed following an electronic search of SCOPUS, PubMed, Web of Science, ScienceDirect, and Google Scholar and two Chinese electronic databases, CNKI and Wan Fang. All articles published in English and Chinese between January 2010 and January 2022 that quantified autophagy-related proteins in aging skeletal muscle models.

Results: The primary outcome was autophagy assessment, indicated by changes in the levels of any autophagy-associated proteins. A total of fifteen studies were included in the final review. Chronic exercise modes mainly comprise aerobic exercise and resistance exercise, and the intervention types include treadmill training, voluntary wheel running, and ladder training. LC3, Atg5-Atg7/9/12, mTOR, Beclin1, Bcl-2, p62, PGC-1α, and other protein levels were quantified, and the results showed that long-term aerobic exercise and resistance exercise could increase the expression of autophagy-related proteins in aging skeletal muscle (p < 0.05). However, there was no significant difference in short term or high-intensity chronic exercise, and different types and intensities of exercise yielded different levels of significance for autophagy-related protein expression.

Conclusion: Existing evidence reveals that high-intensity exercise may induce excessive autophagy, while low-intensity exercise for a short period (Intervention duration <12 weeks, frequency <3 times/week) may not reach the threshold for exercise-induced autophagy. Precise control of the exercise dose is essential in the long term to maximize the benefits of exercise. Further investigation is warranted to explore the relationship between chronic exercise and different exercise duration and types to substantiate the delaying of skeletal muscle aging by exercise.

Sarcopenia in Menopausal Women: Current Perspectives

Menopause is associated with hormonal changes, which could accelerate or lead to sarcopenia. Functional impairment and physical disability are the major consequences of sarcopenia. In order to hamper these negative health outcomes, it appears necessary to prevent and even treat sarcopenia, through healthy lifestyle changes including diet and regular physical activity or through hormonal replacement therapy when appropriate. Therefore, the purpose of this narrative review will be 1) to present the prevalence of sarcopenia in postmenopausal women; 2) to address the risk factors related to sarcopenia in this specific population; and 3) to discuss how to manage sarcopenia among postmenopausal women.

A multistrain probiotic reduces sarcopenia by modulating Wnt signaling biomarkers in patients with chronic heart failure

BACKGROUND

The muscle decline due to aging, called sarcopenia and functional compromise, are common occurrences in patients with chronic heart failure (CHF). Intestinal dysbiosis and the alterations in Wnt signaling may partly account for these findings. We investigated the effects of a multistrain probiotic on Wnt signaling biomarkers and their associations with sarcopenia and functional capacity in CHF patients.

METHODS

The CHF patients were randomized into placebo (n = 48) and probiotic (n = 44) groups for 12 weeks. We measured circulating markers of intestinal permeability (zonulin) and Wnt signaling (dickkopf-1, Dkk-1; dickkopf-3, Dkk-3), and sterol regulatory element-binding protein-1 (SREBP1), handgrip strength (HGS), and short physical performance battery (SPPB) scores at baseline and after probiotics treatment.

RESULTS

Probiotics treatment improved HGS, gait speed, and plasma Dkk-1, and reduced plasma zonulin, Dkk-3, and SREBP1 in CHF patients (all p < 0.05). Among sarcopenia indexes, HGS showed robust correlations with the three Wnt biomarkers (all p < 0.05). Probiotic treatment also improved the SPPB scores in CHF patients, which were strongly correlated with Dkk-3, followed by Dkk-1, and SREBP1 (all p < 0.05). SREBP1 and Dkk-3 demonstrated significant potential in diagnosing sarcopenia in CHF patients. Probiotics also reduced the plasma markers of inflammation and oxidative stress in CHF patients.

CONCLUSION

The multistrain probiotic reduces sarcopenia and improves functional capacity in CHF patients by modulating Wnt signaling.

Lysyl oxidase-like 2 inhibitor rescues D-galactose-induced skeletal muscle fibrosis

Aging-related sarcopenia is currently the most common sarcopenia. The main manifestations are skeletal muscle atrophy, replacement of muscle fibers with fat and fibrous tissue. Excessive fibrosis can impair muscle regeneration and function. Lysyl oxidase-like 2 (LOXL2) has previously been reported to be involved in the development of various tissue fibrosis. Here, we investigated the effects of LOXL2 inhibitor on D-galactose (D-gal)-induced skeletal muscle fibroblast cells and mice. Our molecular and physiological studies show that treatment with LOXL2 inhibitor can alleviate senescence, fibrosis, and increased production of reactive oxygen species in fibroblasts caused by D-gal. These effects are related to the inhibition of the TGF-β1/p38 MAPK pathway. Furthermore, in vivo, mice treatment with LOXL2 inhibitor reduced D-gal-induced skeletal muscle fibrosis, partially enhanced skeletal muscle mass and strength and reduced redox balance disorder. Taken together, these data indicate the possibility of using LOXL2 inhibitors to prevent aging-related sarcopenia, especially with significant fibrosis.

Network pharmacology-based analysis of the effects of puerarin on sarcopenia

Background

With the acceleration of population aging, sarcopenia will place a heavy burden on families and society. Thus, effective treatments urgently need to be developed to slow down the development of sarcopenia. This study adopted a network pharmacological approach to explore the possible mechanisms of puerarin in treating sarcopenia.

Methods

The potential therapeutic targets of puerarin were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database, while the targets of sarcopenia were obtained from the GeneCards, DisGeNET, Online Mendelian Inheritance in Man (OMIM), and Therapeutic Target Database (TTD) databases. The protein-protein interaction (PPI) network was generated by BisoGenet, and core targets were identified by a topological analysis. To determine the potential targeting pathways, the core targets were further imported into the Metascape platform for the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The results were visualized using an online bioinformatics tool.

Results

We identified 53 targets for puerarin and 129 targets for sarcopenia. A total of 206 core targets, which were considered potential therapeutic targets, were identified from the merged PPI network. Further, the GO and KEGG analyses revealed that the functions of the core targets and related pathways were mainly associated with the cell cycle, apoptosis, protein synthesis, and proteolysis.

Conclusions

Puerarin has the potential to treat sarcopenia through the regulation of the cell cycle, apoptosis, and protein homeostasis. Our study has laid a foundation for further studies on drug development and pharmacological experiments in the treatment of sarcopenia.

Psoas muscle index is related to hip fracture in osteoporosis: a cross-sectional MRI study

OBJECTIVE

The aim of this study was to investigate the properties of psoas muscle in osteoporotic patients in lumbar magnetic resonance imaging (MRI) scan and their relationship with hip fracture.

MATERIALS AND METHODS

One hundred seventy-seven patients with osteoporosis (63.69 ± 9.677, 105 female) who had received lumbar spine MRI and dual-energy X-ray absorptiometry (DXA) examinations were retrospectively included. Thickness (PMT), cross-sectional areas (CSA), and index (PMI) values were measured for psoas muscle at L3 level and psoas muscle characteristics were compared between hip fracture and control groups.

RESULTS

PMT, CSA, and PMI values were statistically significantly different between hip fracture and control groups (respectively p < .001, p < .05, p < .01). The results showed that there was a significant association between being sarcopenic and having hip fracture (χ² (1, n = 117) = 4.57, p < .05, phi = .20).

CONCLUSION

PMT, CSA, and PMI might be associated with hip fracture in osteoporotic patients. However, this association is independent of bone mineral density (BMD). Psoas muscle features including PMT, CSA, and PMI should be used as significant predictors of falls and fractures in osteoporotic patients.

The Key Role of Nutritional Elements on Sport Rehabilitation and the Effects of Nutrients Intake

Adequate nutrition is of utmost importance for athletes, especially during rehabilitation after injury in order to achieve fast healing and return to sports. The aim of this narrative review is to define the proper nutritional elements for athletes to meet their needs and facilitate their fast return to sports after surgery or injury, as well as determine the effects of specific nutrients intake. Studies on antioxidants, which are substances that protect against free radicals, for the injured athlete are few and unclear, yet poly-phenols and especially flavonoids might improve healing and inflammation following an injury. Benefits of vitamin C or E on muscle damage are disputable in relevant studies, while optimal levels of vitamin D and calcium contribute to bone healing. Minerals are also essential for athletes. Other supplements suggested for muscle damage treatment and protein synthesis include leucine, creatine, and hydroxymethylbutyrate. Diets that include high-quality products, rich in micronutrients (like vitamins, minerals, etc.) bio-active compounds and other nutritional elements (like creatine) are suggested, while an individualized nutrition program prescribed by a trained dietitian is important. Further studies are needed to clarify the underlying mechanisms of these nutritional elements, especially regarding injury treatment.

Application of a Social-Ecological Model to Study the Factors Associated With Sarcopenia

The social-ecological model (SEM) provides a framework for developing multidimensional preventive strategies at the intrapersonal, interpersonal, organizational, community, and policy levels. While sarcopenia forms due to multiple factors, the SEM has not yet been applied to the prevention of sarcopenia. We aimed to categorize the factors associated with sarcopenia in each level of the SEM.

The electronic databases were searched between 2010 and 2021 to collect factors associated with sarcopenia. Information from guidelines, reference lists, and expert consultation was further hand-searched. The factors mentioned in the reviewed studies were classified into the SEM.

In 17 studies, 42 factors associated with sarcopenia were identified; thereafter, 33 biological and individual factors were categorized at the intrapersonal level, isolation was categorized at the interpersonal level, a sedentary lifestyle was at the organizational level, community involvement and social capital were at the community level, as well as knowledge about the disease, disability, income, education, and residential area were categorized at the policy level. The categorization of factors associated with sarcopenia, based on the SEM level, may be useful in the development of preventive strategies; however, further research is required.

Feasibility of 18F-Fluorocholine PET for Evaluating Skeletal Muscle Atrophy in a Starved Rat Model

Imaging techniques for diagnosing muscle atrophy and sarcopenia remain insufficient, although various advanced diagnostic methods have been established. We explored the feasibility of ¹⁸F-fluorocholine (¹⁸F-FCH) positron emission tomography/computed tomography (PET/CT) for evaluating skeletal muscle atrophy, as an imaging technique that tracks choline level changes in muscles. Cell uptake in L6 cells by ¹⁸F-FCH was performed in a complete medium containing serum (untreated group, UN) and a serum-free medium (starved group, ST). Small-animal-dedicated PET/CT imaging with ¹⁸F-FCH was examined in in-vivo models with rats that were starved for 2 days to cause muscle atrophy. After the hind limbs were dissected, starvation-induced in-vivo models were anatomically confirmed by reverse-transcription polymerase chain reaction to evaluate the expression levels of the atrophy markers muscle RING-finger protein-1 (MuRF-1) and atrogin-1. ¹⁸F-FCH uptake was lower in the starvation-induced cells than in the untreated group, and in-vivo PET uptake also revealed a similar tendency (the average standardized uptake value (SUV_mean) = 0.26 ± 0.06 versus 0.37 ± 0.07, respectively). Furthermore, the expression levels of MuRF-1 and atrogin-1 mRNA were significantly increased in the starvation-induced muscle atrophy of rats compared to the untreated group. ¹⁸F-FCH PET/CT may be a promising tool for diagnosing skeletal muscle atrophy.

Relationship between tooth loss and sarcopenia in suburban community-dwelling older adults in Shanghai and Tianjin of China

Both sarcopenia and loss of teeth are associated with aging. The purpose of this study was to investigate potential relationships between tooth loss and sarcopenia and its components in suburban community-dwelling older adults of Shanghai and Tianjin, China. The subjects were 1494 people over 60 years of age (40.7% men; aged 71.64 ± 5.97 years) from Chongming District of Shanghai and Hangu District of Tianjin. Asian Working Group for Sarcopenia(AWGS) criteria were used to define sarcopenia. Muscle mass, muscle strength, and physical performance were assessed using a bioelectrical impedance analyzer, a grip strength test, and a four-meter walk test, respectively. The subjects were divided into groups depending on self-reported loss of teeth. Our studies found no correlation between tooth loss and sarcopenia or muscle mass. However, the walking speed of female participants with at least 10 teeth lost was 0.059 m/s slower than that of participants with fewer than 10 teeth lost (p < 0.001), and grip strength was 1.577 kg lower among male participants with at least 10 teeth lost than among males with fewer than 10 teeth lost (p = 0.023). These results are consistent with the importance of good oral hygiene in preventing declines of physical performance in older adults.

Sarcopenia and Myosteatosis Are Associated with Neutrophil to Lymphocyte Ratio but Not Glasgow Prognostic Score in Colorectal Cancer Patients

Cancer patients commonly present sarcopenia, myosteatosis, and systemic inflammation, which are risk factors of poor survival. In this study, sarcopenia and myosteatosis were defined from preoperative body computed tomography scans of 222 colorectal cancer (CRC) patients and analyzed in relation to tumor and patient characteristics, markers of systemic inflammation (modified Glasgow prognostic score (mGPS), neutrophil−lymphocyte ratio (NLR), serum levels of C-reactive protein (CRP), albumin, and 13 cytokines, and survival. Of the systemic inflammation markers, sarcopenia and/or myosteatosis associated with elevated NLR (p = 0.005) and low albumin levels (≤35 g/L) (p = 0.018), but not with mGPS or serum cytokine levels. In addition, myosteatosis was associated with a proximal tumor location (p = 0.039), serrated tumor subtype (p < 0.001), and severe comorbidities (p = 0.004). Multivariable analyses revealed that severe comorbidities and serrated histology were independent predictors of myosteatosis, and older age and elevated NLR were independent indicators of sarcopenia. Myosteatosis associated with shorter overall survival in univariable analysis (HR 1.959, 95% CI 1.24−3.10, p = 0.004) but not in multivariable analysis (p = 0.075). We conclude that sarcopenia and myosteatosis were associated with inflammatory marker NLR, but not with mGPS. Moreover, patients with serrated CRC may have an increased risk of myosteatosis. Myosteatosis or sarcopenia were not independent predictors of patient survival.