Standing-Long-Jump Test Application in Identifying Female Adolescents at Risk of Sarcopenic Obesity

SUMMARY: The identification of children and adolescents who are at risk of sarcopenic obesity development often requires specialized equipment and expensive test procedures. Therefore, the establishment of cheaper and faster methods would be greatly useful, especially if they could be applied in the field. The study's objective was to establish if identification of female adolescents who suffer the risk of developing sarcopenic obesity can be obtained through the standing-long-jump test application. To achieve the research objectives, various anthropometric and body composition measurements were performed and lower limb explosive strength was assessed using the standing long jump fitness test. The research was conducted on a sample of 535 female respondents randomly selected from 9 elementary schools in the Skopje region of the Republic of North Macedonia. The respondents were divided into quintiles according to BMI z-scores, and the arithmetic means and SD about muscle-to-fat ratio were calculated for each quintile. The cutoff was determined based on the mean and standard deviation of the muscle-to-fat ratio for the 3rd quintile of BMI and the percentage of respondents with sarcopenic obesity was examined. The optimal cut-off value of the long jump fitness test results for predicting sarcopenic obesity in an adolescent girl showed that the area under the ROC curve was 0.781 (95 % CI 0.743-0.815). The standing-long-jump test values, on grounds of odds ratio (OR 95 % CI) about the girls at risk of sarcopenic obesity development, which was identified on muscle-to-fat ratio base, were 8.76 (4.39 - 17.54, p 0.001). It can be used to predict sarcopenic obesity presence in female adolescents, which can be vital in case of health intervention.

La identificación de niños y adolescentes que corren riesgo de desarrollar obesidad sarcopénica a menudo requiere equipos especializados y procedimientos de pruebas costosos. Por lo tanto, el establecimiento de métodos más baratos y rápidos sería de gran utilidad, especialmente si pudieran aplicarse en el campo. El objetivo del estudio fue establecer si la identificación de mujeres adolescentes que sufren riesgo de desarrollar obesidad sarcopénica se puede obtener mediante la aplicación de la prueba de salto de longitud de pie. Para lograr los objetivos de la investigación, se realizaron diversas mediciones antropométricas y de composición corporal y se evaluó la fuerza explosiva de los miembros inferiores mediante la prueba de aptitud de salto de longitud de pie. La investigación se realizó con una muestra de 535 mujeres encuestadas seleccionadas al azar de 9 escuelas primarias de la región de Skopje, en la República de Macedonia del Norte. Los encuestados se dividieron en quintiles según las puntuaciones z del IMC, y se calcularon las medias aritméticas y la DE sobre la relación músculo-grasa para cada quintil. El límite se determinó en función de la media y la desviación estándar de la relación músculo-grasa para el tercer quintil del IMC y se examinó el porcentaje de encuestados con obesidad sarcopénica. El valor de corte óptimo de los resultados de la prueba de condición física de salto de longitud para predecir la obesidad sarcopénica en una adolescente mostró que el área bajo la curva ROC fue 0,781 (IC del 95 %: 0,743-0,815). Los valores de la prueba de salto de longitud de pie, sobre la base del odds ratio (OR IC del 95 %) sobre las niñas en riesgo de desarrollar obesidad sarcopénica, que se identificó sobre la base del ratio músculo-grasa, fueron 8,76 (4,39 - 17,54, p. 0,001). Puede utilizarse para predecir la presencia de obesidad sarcopénica en adolescentes, lo que puede ser vital en caso de intervención sanitaria.

Physical activity, protein consumption, and loss of muscle mass in older adult participants of the ELSA-Brazil study / Atividade física, consumo de proteínas e perda de massa muscular em idosos do ELSA-Brasil

Objetivo: Objetiva-se avaliar a relação entre consumo de proteínas (CP), atividade física (AF) e massa muscular (MM) em indivíduos com 60 anos ou mais de idade. Metodologia: Trata-se de um estudo prospectivo a partir da linha de base e segunda onda do estudo ELSA-Brasil. O CP foi avaliado por meio de um questionário de frequência alimentar semiquantitativo (QFA). A AF foi mensurada pelo International Physical Activity Questionnaire (IPAQ). A MM foi estimada por meio de equação de predição, e calculada a diferença de MM entre a 2a e a 1a onda. Análises bivariadas foram realizadas adotando o valor de p < 0,05. Para as análises multivariadas, utilizou-se a regressão de Poisson, com quatro modelos distintos, que incluíram as covariáveis com valor de p < 0,20. Utilizou-se o pacote estatístico SPSS versão 21. Resultados: A amostra foi constituída de 2216 idosos, sendo 55,10% de mulheres, com média de idade de 65,20 ± 4,15. Indivíduos com redução de MM entre as duas ondas estão situados no primeiro quartil de consumo de proteína. Além disso, a média de AF mostrou diferença significativa entre os grupos e a AF no lazer apenas para as mulheres (p < 0,05). Após ajuste por variáveis sociodemográficas, de saúde e hábitos de vida, indivíduos com menor consumo de proteínas apresentaram risco de 1,45 (1,29 ­ 1,63) de apresentar MM diminuída. Conclusões: O menor CP e AF forte estão associados à MM diminuída, e aqueles com menor CP no primeiro e segundo quartis apresentam maior risco de possuir MM diminuída. (AU)

Objective: The objective was to evaluate the relationship between protein consumption, physical activity, and muscle mass in individuals aged ≥ 60 years. Methods: This prospective study was based on the baseline and second wave of the ELSA Brazil study. Protein consumption was assessed using a semiquantitative food frequency questionnaire. Physical activity was measured using the International Physical Activity Questionnaire. Muscle mass was estimated using a prediction equation, and the difference in MM between the first and second waves was calculated. Bivariate analyses were performed, with p < 0.05 considered significant. Multivariate analysis consisted of 4 Poisson regression models including covariates with p < 0.20. The statistical analysis was performed in IBM SPSS Statistics 21. Results: The sample included 2216 older adults, 55.10% of whom were women, with a mean age of 65.20 (SD, 4.15). Participants whose muscle mass decreased between the waves were in the first quartile of protein consumption. Mean physical activity significantly differed between the groups, while leisure-time physical activity differed only for women (p < 0.05). After adjusting for sociodemographic, health, and lifestyle variables, participants with lower protein intake had a 1.45 (1.29­1.63) relative risk of muscle mass loss. Conclusions: Lower protein consumption and higher physical activity were associated with decreased muscle mass, and those with protein consumption in the first and second quartiles are at higher risk of muscle mass loss. (AU)

Ângulo de fase como preditor de massa muscular em pacientes com doença inflamatória intestinal / Phase angle as a predictor of muscle mass in patients with inflammatory bowel disease

ABSTRACT Malnutrition/sarcopenia is frequent in patients with inflammatory bowel diseases (IBD), and results in muscle catabolism, impacting treatment response, postoperative complications, and quality of life. Objective: This study aims to assess whether the phase angle (PhA) is a parameter for predicting reduced muscle mass in patients with IBD. Methods: Adult patients with IBD were included in this cross-sectional study. For the estimation of muscle mass and the calculation of the PhA, we used bioelectrical impedance analysis (BIA). Crohn's disease (CD) and ulcerative colitis (UC) activity scores were defined using the Harvey-Bradshaw index and partial Mayo score, respectively. The area under the ROC curve was calculated to identify the PhA cut-off point for reduced muscle mass. Results: The sample consisted of 145 patients, with 39 (26.9%) with IBD in the active phase. There was a correlation of the PhA with skeletal muscle mass (SMM) (rs 0.35, P<0.001) and with the skeletal muscle mass index (SMI) (rs 0.427, P<0.001), and the associations remained in the most active form (moderate or severe) of IBD. The ROC curve analysis indicated that the cut-offs points of the PhA ≤5.042 for female and PhA ≤6.079 for male can be used to predict muscle mass reduction. Conclusion: The PhA can be considered a predictor of muscle mass reduction in IBD patients, and we can use it for screening and monitoring the evolution of malnutrition.

RESUMO A desnutrição/sarcopenia é frequente em pacientes com doenças inflamatórias intestinais (DII), resultando em catabolismo muscular, com impacto nas respostas aos tratamentos, complicações cirúrgicas e na qualidade de vida. Objetivo: Este estudo tem como objetivo, avaliar se o ângulo de fase (AF) é um parâmetro para a predição de redução de massa muscular em pacientes com DII. Métodos: Pacientes adultos com DII foram incluídos neste estudo transversal. A estimativa da massa muscular e o cálculo do AF foram realizados a partir do exame de bioimpedância elétrica (BIA). As atividades da doença de Crohn e retocolite ulcerativa foram definidas pelo índice Harvey-Bradshaw e escore parcial de Mayo, respectivamente. A área de curva ROC foi calculada para identificar o ponto de corte do AF para a massa muscular reduzida. Resultados: A amostra foi composta por 145 pacientes, sendo 39 (26.9%) com DII em fase ativa. Houve correlação do AF com massa muscular esquelética (MME) (rs 0.35, P<0.001) e com o índice de massa muscular esquelética (IMME) (rs 0.427, P<0.001), mantendo-se as associações na forma mais ativa (moderada ou grave) da DII. A análise da curva ROC indicou que os pontos de corte de AF ≤5.042 para mulheres e ≤6.079 para homens podem ser usados para prever a redução da massa muscular. Conclusão: O AF pode ser considerado um preditor de redução de massa muscular nos pacientes com DII e ser utilizado para triagem e acompanhamento da evolução da desnutrição.

Relationship between skeletal muscle mass loss and metabolic dysfunction-associated fatty liver disease among Chinese patients with metabolic dysregulation

SUMMARY OBJECTIVE: The aim of this study was to explore the correlation between skeletal muscle content and the presence and severity of metabolic dysfunction-associated fatty liver disease in patients with metabolic dysregulation in China. METHODS: A cross-sectional study was conducted among patients from the endocrinology outpatient department at Ningbo First Hospital, in Ningbo, China, in April 2021. Adult patients with metabolic dysregulation who accepted FibroScan ultrasound were included in the study. However, those without clinical data on skeletal muscle mass were excluded. FibroScan ultrasound was used to noninvasively evaluate metabolic dysfunction-associated fatty liver disease. The controlled attenuation parameter was used as an evaluation index for the severity of liver steatosis. Bioelectrical impedance analysis was used to measure the skeletal muscle index. RESULTS: A total of 153 eligible patients with complete data were included in the final analysis. As the grading of liver steatosis intensifies, skeletal muscle index decreases (men: Ptrend<0.001, women: Ptrend=0.001), while body mass index, blood pressure, blood lipid, uric acid, aminotransferase, and homeostatic model assessment of insulin resistance increase (Ptrend<0.01). After adjusting for confounding factors, a negative association between skeletal muscle index and the presence of metabolic dysfunction-associated fatty liver disease was observed in men (OR=0.691, p=0.027) and women (OR=0.614, p=0.022). According to the receiver operating characteristic curve, the best cutoff values of skeletal muscle index for predicting the metabolic dysfunction-associated fatty liver disease presence were 40.37% for men (sensitivity, 87.5%; specificity, 61.5%) and 33.95% for women (sensitivity, 78.6%; specificity, 63.8%). CONCLUSION: Skeletal muscle mass loss among patients with metabolic dysregulation was positively associated with metabolic dysfunction-associated fatty liver disease severity in both sexes. The skeletal muscle index cutoff value could be used to predict metabolic dysfunction-associated fatty liver disease.

Skeletal muscle mass obtained by anthropometric equation and presence of sarcopenia in postmenopausal women

Abstract Objective: To analyze the amount of muscle and the presence of sarcopenia in postmenopausal women using different methods, verifying the agreement between them as to skeletal muscle mass (SMM). Methods: This cross-sectional observational study was conducted with postmenopausal women aged ≥ 50 years. SMM was obtained from a predictive equation, Bioelectrical Impedance (BIA), and Dual Energy X-Ray Absorptiometry (DXA). The skeletal muscle mass index (SMI) and the appendicular skeletal muscle mass index (ASMI) were calculated. The cut-off point of SMI was determined for the population itself. The agreement between the SMI obtained using the different methods was verified. Sarcopenia was diagnosed according to the criteria proposed by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2). The significance level adopted for all tests was 5.0%. Results: A total of 112 women were evaluated, with an average age of 66.1 ± 5.65 years. Among them, 51.8% were sufficiently active and 43.8% were overweight and obese. The SMI cut-offs were 6.46 kg/m2 for the predictive equation and 7.66 kg/m2 for BIA, with high sensitivity and specificity. There was an excellent agreement in the identification of SMM by the predictive equation (0.89 [0.824-0.917], p < 0.001) and BIA (0.92 [0.883-0.945], p < 0.001), in reference to DXA. The prevalence of sarcopenia was 0.9%, 1.8%, and 2.7% according to BIA, DXA, and the predictive equation, respectively. Conclusion: The predictive equation showed the expected agreement in estimating skeletal muscle mass in postmenopausal women, offering a viable and accurate alternative.

Advances of pathogenesis and drug development in amyotrophic lateral sclerosis / 中国药理学通报

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting both upper and lower motor neurons. ALS patients develop progressive muscle atrophy, muscle weak and paralysis, finally died of respiratory failure. ALS is characterized by fast aggression and high mortality. What' s more, the disease is highly heterogeneous with unclear pathogenesis and lacks effective drugs for therapy. In this review, we summarize the main pathological mechanisms and the current drugs under development for ALS, which may provide a reference for the drug discovery in the future.

Association between skeletal muscle mass and metabolic syndrome in middle-aged and elderly community residents / 上海预防医学

ObjectiveTo explore the correlation between skeletal muscle mass and metabolic syndrome （MS） disease risk among middle-aged and elderly community residents in Urumqi， and to provide a theoretical basis for understanding the relationship between skeletal muscle mass and MS among middle-aged and elderly community residents in China. MethodsA total of 1 438 community residents ≥ 50 years old were selected as the research subjects from July 2018 to January 2019 in Urumqi. They were selected from a multi-ethnic natural population cohort in Xinjiang. Data were collected through questionnaires， physical examination， bioelectrical impedance analysis （BIA）， laboratory tests， etc. Skeletal muscle mass was evaluated using the limb skeletal muscle mass index （SMI） corrected for body weight； MS was defined as it at least includes three of the following： abdominal obesity， hypertension， hyperglycemia， high triglycerides and low high-density lipoprotein cholesterol. SMI was divided into four quantile arrays of Q1‒Q4. Trend χ2 test was applied to explore whether there was a correlation between SMI changes and MS. A multivariate logistic regression model was used to analyze whether there is a difference in the risk of MS between the higher SMI group （Q2， Q3， Q4） and the reference group Q1. ResultA total of 560 MS patients were detected in this study， with a prevalence rate of 38.94%. Among them， the prevalence rate of MS was 39.16% in males and 38.80% in females. The increase in male SMI grading level is not correlated with the prevalence of MS （trend P>0.05）； After adjusting for confounding factors （model 4）， the increase in SMI was still not related to the prevalence of MS （Ptrend=0.995）. There was no statistical difference in the risk of MS between the lowest quartile group Q1 and the highest quartile group Q4 （OR=1.01， 95%CI： 0.69‒1.78）. The prevalence of MS in women gradually decreased with the increase of SMI grading level （Ptrend<0.001）； After adjusting for confounding factors （model 4）， there was still a correlation between the increase of SMI and the prevalence of MS （Ptrend=0.005）. With the lowest quartile of SMI Q1 as the reference group， the risk of MS in Q2 （OR=0.63， 95%CI： 0.40‒1.00）， Q3 （OR=0.56， 95%CI： 0.34‒0.94）， Q4 （OR=0.42， 95%CI： 0.23‒0.76） decreased. ConclusionAn increase in skeletal muscle mass may be beneficial for preventing MS， especially among middle-aged and elderly female residents. Considering the intensification of aging in China and the close relationship between MS and related comorbidities， managing skeletal muscle mass may contribute to potential MS prevention.

Activation of Nrf2/HO-1/NQO1 Signaling Pathway by Shenqi Tangluo Pill Improves Oxidative Stress Injury of Skeletal Muscle of Type 2 Diabetes Mellitus Mice / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Shenqi Tangluo pill （SQTLP） on oxidative stress injury of skeletal muscle of type 2 diabetes mellitus （T2DM） mice based on nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1）/NAD（P）H quinone oxidoreductase 1 （NQO1） pathway. MethodA total of 60 7-week-old male db/db mice ［specific pathogen-free （SPF） grade］ were selected and fed for one week for adaption. They were divided into the model control group， SQTLP low-， medium- and high-dose （19， 38， and 76 g·kg-1） groups and metformin group （0.26 g·kg-1） by gavage. Each group consisted of 12 mice. Twelve male db/m mice of the same age were selected as the blank group. The intervention was implemented continuously for 8 weeks. Fasting blood glucose （FBG） was detected. Fasting serum insulin （FINS） levels were detected by enzyme-linked immunosorbent assay （ELISA）， and the homeostasis model assessment-insulin resistance （HOMA-IR） index and the homeostasis model assessment-insulin sensitivity index （HOMA-ISI） were calculated. Oral glucose tolerance test （OGTT） and insulin tolerance test （ITT） were conducted. The activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） and the contents of malondialdehyde （MDA） and reduced nicotinamide adenine dinucleotide phosphate （NADPH） in skeletal muscle tissues were detected by biochemical kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in skeletal muscle tissues. The levels of reactive oxygen species （ROS） and 4-hydroxynonenal （4-HNE） in skeletal muscle tissue were detected by immunofluorescence （IF）. The expression levels of Nrf2， HO-1， NQO1 and glutamate-cysteine ligase catalytic subunit （GCLC） proteins in skeletal muscle tissues were detected by Western blot. ResultCompared with those in the blank group， FBG， FINS and HOMA-IR in the model group were significantly increased （P<0.05）， while HOMA-ISI was decreased （P<0.05）. The results of OGTT and ITT showed that blood glucose was significantly increased at all time points （P<0.05）， and glucose tolerance and insulin tolerance were significantly impaired. SOD and GSH-Px activities in skeletal muscle tissues were significantly decreased （P<0.05）， and MDA and NADPH contents were significantly increased （P<0.05）. In skeletal muscle tissues， the arrangement of muscle fibers was loose， the nucleus was disordered， and inflammatory cells were infiltrated. The expression levels of ROS and 4-HNE in skeletal muscle tissues were significantly increased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly decreased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the metformin group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that blood glucose in the metformin group was significantly decreased at all time points （P<0.05）. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue of the metformin group. The expressions of ROS and 4-HNE in skeletal muscle tissues were decreased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly increased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the SQTLP medium- and high-dose groups were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the glucose tolerance and insulin tolerance of mice were improved in each dose group of SQTLP. The GSH-Px activity in the SQTLP low-dose group was significantly increased （P<0.05）， and the NADPH content was decreased （P<0.05）. The activities of SOD and GSH-Px in the SQTLP medium- and high-dose groups were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. The skeletal muscle tissue injury of mice in each dose group of SQTLP was ameliorated to different degrees. In the SQTLP medium- and high-dose groups， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05）. Compared with those in the SQTLP low-dose group， FBG and HOMA-IR in the SQTLP high-dose group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the SQTLP high-dose group significantly improved the glucose tolerance and insulin tolerance of mice. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05） in the skeletal muscle tissue of the SQTLP high-dose group. ConclusionSQTLP can significantly improve IR in T2DM mice， and the mechanism is related to SQTLP activating the Nrf2/HO-1/NQO1 signaling pathway， promoting the expression of antioxidant enzymes， and thus improving the oxidative stress injury in the skeletal muscle.

COVID-19 related to sarcopenia: Current perspectives on etiology, clinical implications, and nutritional rehabilitation

Sarcopenia is a progressive skeletal muscle disorder characterized by reduced strength and quality. Pathophysiological mechanisms, clinical aspects, and nutritional points were related to sarcopenia in COVID-19 found in skeletal muscle during and after the disease course, which corroborated the development of adverse events. Declining physical activity, insufficient protein intake, and worsened proinflammatory response have been shown to have negative consequences on muscle protein synthesis, potentiating the risk of acute sarcopenia. Obesity sarcopenia has also been shown to worsen the prognosis of patients with SARS-CoV-2. Nutritional rehabilitation is used to prevent or minimize the development of acute sarcopenia. Dietary recommendations include increased energy supply and protein intake of 1.2 to 2.0 g/kg of body weight. Evidence suggests that aging with sedentary behaviors, pathophysiological changes, and inflammation alter body composition. In addition, nutritional deficiencies are predictors and aggravators of acute sarcopenia in COVID-19.

Sarcopenia é um distúrbio progressivo do músculo esquelético caracterizado pela redução da força e qualidade. Mecanismos fisiopatológicos, aspectos clínicos e nutricionais foram relacionados à sarcopenia no COVID-19 encontrada no músculo esquelético, durante e após o curso da doença, o que corroborou para o desenvolvimento de eventos adversos. O declínio da atividade física, a ingestão insuficiente de proteínas e piora da resposta pró-inflamatória demonstraram ter consequências negativas na síntese de proteínas musculares, potencializando risco de sarcopenia. A obesidade sarcopênica também demonstrou piorar o prognóstico de pacientes infectados com SARS-CoV-2. A reabilitação nutricional pode prevenir ou minimizar o desenvolvimento de sarcopenia. As recomendações dietéticas incluem maior oferta de energia e maior ingestão de proteínas de 1,2 a 2,0 g/kg de peso corporal. Evidências sugerem que o envelhecimento com comportamentos sedentários, alterações fisiopatológicas e inflamação, alterações na composição corporal, deficiências nutricionais são preditores e agravantes da sarcopenia aguda na COVID-19.

Sarcopenia em pacientes de 40 a 64 anos hospitalizados por insuficiência cardíaca / Sarcopenia in patients aged 40­64 years hospitalized for heart failure

Introdução: a insuficiência cardíaca (IC) e a sarcopenia são condições prevalentes e inter-relacionadas, figurando como importantes causas de limitações funcionais. Objetivo: avaliar critérios de sarcopenia, e suas relações com parâmetros cardiometabólicos, em pacientes de 40 a 64 anos hospitalizados por IC. Metodologia: estudo de corte transversal com caráter analítico envolvendo indivíduos com IC confirmada. A massa muscular apendicular (MMA) foi avaliada através da absorciometria por raios-X de dupla energia (DXA), considerando-se baixa MMA mulheres com MMA/altura² <5,5 kg/m² ou MMA/índice de massa corporal (IMC) <0,512 e homens com MMA/altura² <7,0 kg/m² ou MMA/IMC <0,789. Baixa força de preensão manual (FPM) foi considerada quando <16 kg em mulheres e <27 kg em homens. Resultados: avaliou-se 109 pacientes (50,5% mulheres), com mediana de idade de 58 anos. Constatou-se baixa MMA em 41,3% e baixa FPM em 64,2%, não havendo correlação significativa entre FPM e MMA em nenhum dos gêneros. Baixa MMA se associou ao gênero masculino (68,9% versus 35,9%; p=0,001), a maiores idades (60,0 [53,0-63,0] versus 57,0 [51,3-60,0] anos; p=0,039) e maiores níveis séricos de paratormônio (48,0 [30,5-94,4] versus 29,9 [23,0-54,1] pg/mL; p=0,009). Baixa FPM se associou a maior sintomatologia cardíaca (75,7% com baixa FPM tinham classificação funcional da New York Heart Association III-IV, versus 51,3% daqueles com FPM normal; p=0,009). Conclusões: há uma relevante prevalência de sarcopenia em pacientes de 40 a 64 anos hospitalizados por IC, observando-se maior frequência de baixa MMA nos homens, associação entre baixa FPM e sintomatologia cardíaca, e maiores níveis de paratormônio naqueles com perda muscular.

Introduction: heart failure (HF) and sarcopenia are prevalent and interrelated conditions, being important causes of functional limitations. Objective: to evaluate sarcopenia criteria, and their relationship with cardiometabolic parameters, in patients aged 40­64 years hospitalized for HF. Methodology: Cross-sectional study including patients with established HF. Appendicular skeletal muscle mass (ASMM) was assessed using dual-energy X-ray absorptiometry (DXA), considering low ASMM women with ASMM/height² <5.5 kg/m² or ASMM/body mass index (BMI) <0.512 and men with ASMM/height² <7.0 kg/m² or ASMM/BMI <0.789. Low handgrip strength (HGS) was considered when <16 kg in women and <27 kg in men. Results: we evaluated 109 patients (50.5% women), with a median age of 58 years. Low ASMM was found in 41.3% and low HGS in 64.2%, with no significant correlation between HGS and ASMM in either gender. Low ASMM was associated with male gender (68.9% versus 35.9%; p=0.001), older age (60.0 [53.0-63.0] versus 57.0 [51.3-60, 0] years; p=0.039) and higher serum parathyroid hormone (48.0 [30.5-94.4] versus 29.9 [23.0-54.1] pg/mL; p=0.009). Low HGS was associated with greater cardiac symptoms (75.7% with low HGS had a New York Heart Association III-IV functional classification, versus 51.3% of those with normal HGS; p=0.009). Conclusions: there is a relevant prevalence of sarcopenia in patients aged 40­64 years hospitalized for HF, observing a higher frequency of low ASMM in men, an association between low HGS and cardiac symptoms, and higher levels of parathyroid hormone in those with muscle wasting.

Predictive factors of the contracture test for diagnosing malignant hyperthermia in a Brazilian population sample: a retrospective observational study

Abstract Introduction Malignant Hyperthermia (MH) is a pharmacogenetic, hereditary and autosomal dominant syndrome triggered by halogenates/succinylcholine. The In Vitro Contracture Test (IVCT) is the gold standard diagnostic test for MH, and it evaluates abnormal skeletal muscle reactions of susceptible individuals (earlier/greater contracture) when exposed to caffeine/halothane. MH susceptibility episodes and IVCT seem to be related to individual features. Objective To assess variables that correlate with IVCT in Brazilian patients referred for MH investigation due to a history of personal/family MH. Methods We examined IVCTs of 80 patients investigated for MH between 2004‒2019. We recorded clinical data (age, sex, presence of muscle weakness or myopathy with muscle biopsy showing cores, genetic evaluation, IVCT result) and IVCT features (initial and final maximum contraction, caffeine/halothane concentration triggering contracture of 0.2g, contracture at caffeine concentration of 2 and 32 mmoL and at 2% halothane, and contraction after 100 Hz stimulation). Results Mean age of the sample was 35±13.3 years, and most of the subjects were female (n=43 or 54%) and MH susceptible (60%). Of the 20 subjects undergoing genetic investigation, 65% showed variants in RYR1/CACNA1S genes. We found no difference between the positive and negative IVCT groups regarding age, sex, number of probands, presence of muscle weakness or myopathy with muscle biopsy showing cores. Regression analysis revealed that the best predictors of positive IVCT were male sex (+12%), absence of muscle weakness (+20%), and personal MH background (+17%). Conclusions Positive IVCT results have been correlated to male probands, in accordance with early publications. Furthermore, normal muscle strength has been confirmed as a significant predictor of positive IVCT while investigating suspected MH cases.

Stress perception among the elderly and its effect on some muscle strength parameters

Background: With improvement in living conditions in the population and the availability of treatments for various communicable and non-communicable diseases, the life expectancy and consequently the elderly population have increased. Stress leads to mental and physical problems. Aim and Objective: The aim of this study was to assess the effect of stress on muscle functions in the elderly. Materials and Methods: One hundred apparently healthy persons (50 males and 50 females) took part in the study. Perceived stress scale was used to measure their level of stress. Maximum voluntary contraction (MVC) and endurance time were measured with the help of a handgrip dynamometer. Results: The elderly population sample in our study showed a moderate level of stress, but there was no significant difference between the three age groups under study. Conclusion: A significant positive correlation between MVC and stress level was observed in our study subjects.

The CB1 cannabinoid receptor regulates autophagy in the tibialis anterior skeletal muscle in mice

The endocannabinoid system (ECS) regulates energy metabolism, has been implicated in the pathogenesis of metabolic diseases and exerts its actions mainly through the type 1 cannabinoid receptor (CB1). Likewise, autophagy is involved in several cellular processes. It is required for the normal development of muscle mass and metabolism, and its deregulation is associated with diseases. It is known that the CB1 regulates signaling pathways that control autophagy, however, it is currently unknown whether the ECS could regulate autophagy in the skeletal muscle of obese mice. This study aimed to investigate the role of the CB1 in regulating autophagy in skeletal muscle. We found concomitant deregulation in the ECS and autophagy markers in high-fat diet-induced obesity. In obese CB1-KO mice, the autophagy-associated protein LC3 II does not accumulate when mTOR and AMPK phosphorylation levels do not change. Acute inhibition of the CB1 with JD-5037 decreased LC3 II protein accumulation and autophagic flux. Our results suggest that the CB1 regulates autophagy in the tibialis anterior skeletal muscle in both lean and obese mice.

Clinical significance of sarcopenia in patients undergoing treatment for gastric cancer

SUMMARY OBJECTIVE: The aim of this study was to investigate the impact of sarcopenia on prognosis in patients with gastric cancer in order to explore the relationship between sarcopenia and postoperative complications as well as durations of hospital stay and intensive care unit. METHODS: A total of 175 patients who visited the oncology clinic between 2017 and 2022 with respect to their radiological images, demographic data, and laboratory parameters were perused. The OsiriX software was used to measure the skeletal muscle area that was divided by the body height in order to obtain the skeletal muscle index. RESULTS: A total of 50.28% of 175 patients (41 females and 134 males, with a mean age of 63.5 years) who met the inclusion criteria in the study were sarcopenic. Significant differences appeared between sarcopenic and non-sarcopenic patients with respect to durations of both hospital stay (p<0.01) and intensive care unit stay (p<0.01) (multivariate analysis). Furthermore, patients with sarcopenia had significantly frequent postoperative complications in comparison with those without sarcopenia. Among the patients with sarcopenia, decreased levels of hemoglobin and albumin as well as lymphocytes were encountered in terms of inflammatory markers; nevertheless, no significant differences were determined among other inflammatory markers. CONCLUSION: In patients undergoing treatment for gastric cancer, sarcopenia increases postoperative complications and prolongs hospital and intensive care stays during the treatment process.

Cholic and deoxycholic acids induce mitochondrial dysfunction, impaired biogenesis and autophagic flux in skeletal muscle cells

BACKGROUND: Skeletal muscle is sensitive to bile acids (BA) because it expresses the TGR5 receptor for BA. Cholic (CA) and deoxycholic (DCA) acids induce a sarcopenia-like phenotype through TGR5-dependent mechanisms. Besides, a mouse model of cholestasis-induced sarcopenia was characterised by increased levels of serum BA and muscle weakness, alterations that are dependent on TGR5 expression. Mitochondrial alterations, such as decreased mitochondrial potential and oxygen consumption rate (OCR), increased mitochondrial reactive oxygen species (mtROS) and unbalanced biogenesis and mitophagy, have not been studied in BA-induced sarcopenia.METHODS: We evaluated the effects of DCA and CA on mitochondrial alterations in C2C12 myotubes and a mouse model of cholestasis-induced sarcopenia. We measured mitochondrial mass by TOM20 levels and mitochondrial DNA; ultrastructural alterations by transmission electronic microscopy; mitochondrial biogenesis by PGC-1α plasmid reporter activity and protein levels by western blot analysis; mitophagy by the co-localisation of the MitoTracker and LysoTracker fluorescent probes; mitochondrial potential by detecting the TMRE probe signal; protein levels of OXPHOS complexes and LC3B by western blot analysis; OCR by Seahorse measures; and mtROS by MitoSOX probe signals. RESULTS: DCA and CA caused a reduction in mitochondrial mass and decreased mitochondrial biogenesis. Interestingly, DCA and CA increased LC3II/LC3I ratio and decreased autophagic flux concordant with raised mitophagosome-like structures. In addition, DCA and CA decreased mitochondrial potential and reduced protein levels in OXPHOS complexes I and II. The results also demonstrated that DCA and CA decreased basal, ATP-linked, FCCP-induced maximal respiration and spare OCR. DCA and CA also reduced the number of cristae. In addition, DCA and CA increased the mtROS. In mice with cholestasis-induced sarcopenia, TOM20, OXPHOS complexes I, II and III, and OCR were diminished. Interestingly, the OCR and OXPHOS complexes were correlated with muscle strength and bile acid levels. CONCLUSION: Our results showed that DCA and CA decreased mitochondrial mass, possibly by reducing mitochondrial biogenesis, which affects mitochondrial function, thereby altering potential OCR and mtROS generation. Some mitochondrial alterations were also observed in a mouse model of cholestasis-induced sarcopenia characterised by increased levels of BA, such as DCA and CA.

NEDD4-1 deficiency impairs satellite cell function during skeletal muscle regeneration

BACKGROUND: Satellite cells are tissue-specific stem cells primarily responsible for the regenerative capacity of skeletal muscle. Satellite cell function and maintenance are regulated by extrinsic and intrinsic mechanisms, including the ubiquitin-proteasome system, which is key for maintaining protein homeostasis. In this context, it has been shown that ubiquitin-ligase NEDD4-1 targets the transcription factor PAX7 for proteasome-dependent degradation, promoting muscle differentiation in vitro. Nonetheless, whether NEDD4-1 is required for satellite cell function in regenerating muscle remains to be determined. RESULTS: Using conditional gene ablation, we show that NEDD4-1 loss, specifically in the satellite cell population, impairs muscle regeneration resulting in a significant reduction of whole-muscle size. At the cellular level, NEDD4-1-null muscle progenitors exhibit a significant decrease in the ability to proliferate and differentiate, contributing to the formation of myofibers with reduced diameter. CONCLUSIONS: These results indicate that NEDD4-1 expression is critical for proper muscle regeneration in vivo and suggest that it may control satellite cell function at multiple levels.

Six-week Aerobic Exercise Improves Oxidative Damage of Skeletal Muscles and Promotes Myokine Production in Atherosclerotic Mice / 中国生物化学与分子生物学报

Atherosclerosis involving peripheral arteries can cause skeletal muscle lesions, in which oxidative damage is an important manifestation, and atherosclerosis also reduces the production and secretion of beneficial myokines. Irisin, musclin and β-aminoisobutyric acid (BAIBA) are thought to be involved in improving atherosclerosis. However, the molecular mechanism of atherosclerosis-induced skeletal muscle lesions and the effects of aerobic exercise training on the oxidative damage of skeletal muscle and myokine production remain unclear. In this study, apolipoprotein E knockout (ApoE

Interleukin-6 in Skeletal Muscle Mass Regulation / 中国生物化学与分子生物学报

Interleukin-6 (IL-6) is a spreading pleiotropic cytokine, with both anti-inflammatory and proinflammatory effects. It not only participates in the body immune responses but also is involved in the biological regulative processes among different organs, tissues, and cells. IL-6 has both anti-inflammatory and pro-inflammatory effects. In the early stage of pathogen infection, IL-6 plays an anti-inflammatory role in the body, and its level is moderately increased in the body to resist inflammation and maintain internal homeostasis. However, a large amount of IL-6 release can cause excessive inflammation and trigger other pathological changes in the body. Il-6 also has the dual effect of stimulating the synthesis and degradation of skeletal muscle protein in regulating skeletal muscle mass. As an important locomotive organ, skeletal muscle is also one of the key targets of IL-6. IL-6 takes part in the biological control of skeletal muscle hypertrophy through regulating muscle satellite cell proliferation and differentiation under specific stresses. In addition IL-6 is also associated with skeletal muscle atrophy induced by aging and other pathological stresses. In addition, during exercise stress, skeletal muscle can also serve as an endocrine organ to secrete and release IL-6 that facilitates the "crosstalk" between skeletal muscle and other organs or tissues. As IL-6 plays as a versatile role in our body, this paper reviews the research progress of the mechanism of IL-6 in the regulation of skeletal muscle mass, which may provide theoretical support for revealing the molecular mechanism of skeletal muscle stresses and adaptations.

Electroacupuncture at acupoints of yangming meridians for sarcopenia: a randomized controlled trial / 中国针灸

OBJECTIVE@#To observe the clinical effect of electroacupuncture at acupoints of yangming meridians for sarcopenia.@*METHODS@#A total of 60 patients with sarcopenia were randomized into an observation group and a control group, 30 cases in each group. In the control group, conventional nutrition intervention for sarcopenia was adopted. In the observation group, on the basis of the treatment in the control group, acupuncture was applied at bilateral Binao (LI 14), Quchi (LI 11), Zusanli (ST 36), Yanglingquan (GB 34), etc.,ipsilateral Quchi (LI 11) and Zusanli (ST 36) were connected to electroacupuncture, with discontinuous wave, 2 Hz in frequency, 1-10 mA in intensity, 2 times a week, with a interval of 3 days. A total of 12-week treatment was required in the two groups. Before and after treatment, the appendicular skeletal muscle mass index (ASMI), grip strength, 6 m-walking time, body fat percentage and body moisture percentage were observed in the two groups.@*RESULTS@#Compared with those before treatment, after treatment, ASMI and grip strength were increased while 6 m-walking time was shortened in the two groups (P<0.05); body fat percentage was decreased while body moisture percentage was increased in the observation group (P<0.05). After treatment, in the observation group, ASMI, grip strength and body moisture percentage were increased (P<0.05), 6 m-walking time was shortened and body fat percentage was decreased (P<0.05) compared with those in the control group.@*CONCLUSION@#Electroacupuncture at acupoints of yangming meridians can effectively improve the skeletal muscle mass, muscle function, body fat percentage and body moisture percentage in patients with sarcopenia, and make the distribution of muscle and fat more reasonable.

Effects of electroacupuncture on gait and proliferation and differentiation of muscle satellite cell in rats with acute blunt trauma of gastrocnemius muscle / 中国针灸

OBJECTIVE@#To observe the effects of electroacupuncture on threshold of pain, gait, proliferation and differentiation of muscle satellite cell in rats with acute blunt trauma of gastrocnemius muscle, and to explore the possible mechanism of electroacupuncture in promoting the repair of acute injury of skeletal muscle.@*METHODS@#A total of 48 SD rats were randomly divided into a blank group (6 rats), a model group (24 rats) and an electroacupuncture group (18 rats). In the model group and the electroacupuncture group, the model of acute blunt trauma of gastrocnemius muscle was established by self-made impactor. In the electroacupuncture group, electroacupuncture was applied at "Chengshan" (BL 57) and "Yanglingquan" (GB 34) on the right side, with disperse-dense wave, in frequency of 2 Hz/100 Hz, once a day, 30 min each time. Electroacupuncture intervention was performed for 3, 7 and 14 days according to the sampling time. On the 1st, 3rd, 7th and 14th days after modeling, the mechanical withdrawal pain threshold of hindfoot was detected by Von Frey method; the standing time and the maximum contact area of the right hindfoot were recorded by Cat Walk XTTM animal gait analysis instrument; the morphology of the right gastrocnemius muscle and the number of inflammatory cells were observed by HE staining; the positive expression of paired box gene 7 (Pax7) and myogenic differentiation (MyoD) of the right gastrocnemius muscle was detected by immunofluorescence.@*RESULTS@#After modeling, the muscle fiber rupture and massive infiltration of red blood cells and inflammatory cells were observed in the right gastrocnemius muscle; after electroacupuncture intervention, the morphology of muscle fiber was intact and the infiltration of inflammatory cells was improved. Compared with the blank group, in the model group, the differences of mechanical withdrawal pain threshold between the left and right foot were increased (P<0.05), the standing time was shortened and the maximum contact area of the right hindfoot was decreased (P<0.05), the number of inflammatory cells and the positive expression of Pax7 and MyoD of the right gastrocnemius muscle were increased (P<0.05) on the 1st, 3rd, 7th and 14th days after modeling. Compared with the model group, in the electroacupuncture group, the differences of mechanical withdrawal pain threshold were decreased (P<0.05), the standing time was prolonged (P<0.05), the number of inflammatory cells of right gastrocnemius muscle was decreased (P<0.05) on the 7th and 14th days after modeling; the maximum contact area of the right hindfoot was increased (P<0.05), the positive expression of MyoD of the right gastrocnemius muscle was increased (P<0.05) on the 3rd, 7th and 14th days after modeling; the positive expression of Pax7 of the right gastrocnemius muscle was increased (P<0.05) on the 3rd day after modeling.@*CONCLUSION@#Electroacupuncture can effectively improve the pain threshold and gait in rats with acute blunt trauma of gastrocnemius muscle, and promote the repair of skeletal muscle injury, the mechanism may be related to the up-regulation of Pax7 and MyoD, so as to promoting the proliferation and differentiation of muscle satellite cell.