Pathogenesis of sarcopenia and the relationship with fat mass: descriptive review

Skeletal muscle atrophy induces memory dysfunction via hemopexin action in healthy young mice

Age-related morbidity has become an increasingly significant issue worldwide. Sarcopenia, the decline in skeletal muscle mass and strength with age, has been reported to be a risk factor for cognitive impairment. Our previous study revealed that skeletal muscle atrophy shifts the onset of memory dysfunction earlier in young Alzheimer's disease mice and found that hemopexin is a myokine responsible for memory loss. This study aimed to elucidate the occurrence of memory impairment due to skeletal muscle atrophy in non-genetically engineered healthy young mice and the involvement of hemopexin. Closed-colony ddY mice at 12-13 weeks of age were used. Both hind limbs were immobilized by cast attachment for 14 d. Casting for 2 weeks induced a loss of skeletal muscle weight. The memory function of the mice was evaluated using a novel object recognition test. The cast-attached mice exhibited memory impairment. Hemopexin levels in the conditioned medium of the skeletal muscle, plasma, and hippocampus were increased in cast-attached mice. Continuous intracerebroventricular hemopexin infusion induced memory deficits in non-cast mice. To investigate whether hemopexin is the main causative factor of cognitive impairment, cast-attached mice were intracerebroventricularly infused with an anti-hemopexin antibody. Cast-induced memory impairment was reversed by the infusion of an anti-hemopexin antibody. These findings provide new evidence that skeletal muscle atrophy causes memory impairment in healthy young mice through the action of hemopexin in the brain.

Impact of fat to muscle ratio with risk of disability on community-dwelling Japanese older adults: A 5-year longitudinal study

PURPOSE

Sarcopenic obesity is a combination of sarcopenia and obesity, which is associated with the onset of disability. Fat to muscle ratio (FMR) is a screening measure that assesses the ratio of muscle mass to fat mass. However, the relationship between the FMR and disability has not been investigated.

METHODS

This study included 11,427 community-dwelling older adults aged ≥65 years enrolled in NCGG-SGS (National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes), a national cohort study in Japan. FMR was measured by the bioelectrical impedance analysis and calculated by dividing fat mass by muscle mass. Cox proportional hazard regression analysis adjusted for covariates was used to investigate the association between FMR and the risk of developing new care needs at 5 years. FMR was divided by about quintile, with quintile 5 as the high.

RESULTS

The high FMR group had the highest incidence of disability at 20.8 % for women and 20.1 % for men. In women, the association between FMR and disability was significantly different for the FMR (hazard risk [HR]: 1.43, 95 % confidence interval [CI]: 1.16-1.75). There was no association between FMR and disability in men (HR: 0.98, 95 %CI: 0.76-1.25). Lagged analyses accounting for reverse causality did not change the relationship.

CONCLUSIONS

FMR is associated with increased risk of disability in women community-dwelling older adults but not among men. Because the rate of decreased muscle strength is faster in men than in women, early decreased muscle strength may affect men's risk of disability more than muscle mass or fat mass.

Associations of muscle mass and strength with depression among US adults: A cross-sectional NHANES study

OBJECTIVES

The aim of our study was to assess the association between muscle mass and strength and depression through a cross-sectional study of the National Health and Nutrition Examination Survey from 2011 to 2014.

METHODS

Muscle mass was calculated by summing the lean body mass of the limbs and muscle strength was assessed by grip strength. Depression was determined by The 9-item Patient Health Questionnaire. We used weighted multivariate logistic regression models to explore the relationship between muscle mass and strength and depression. Generalized additive models were used to test for the presence of nonlinear associations. We then constructed a two-piece-wise linear regression model and performed a recursive algorithm to calculate inflection points. In addition, subgroup analyses and interaction tests were performed.

RESULTS

The study recruited 4871 adults from the United States. In regression models adjusted for all confounding variables, the OR (95 % CI) for the association between grip strength and appendicular lean mass (ALM) and depression were 0.943 (0.903, 0.985), 0.945 (0.908, 0.983), respectively. There was a non-linear association between grip strength and depression with a turning point of 46.3. The OR (95 % CI) before the turning point was 0.920 (0.872, 0.972). The interaction was statistically significant only in the age analysis. There was also a nonlinear association between ALM and depression, but no significant turning point was found. The interaction was statistically significant in the gender and BMI analyses.

CONCLUSION

Grip strength and ALM are negatively associated with an increased likelihood of depression in US adults. Exercises for muscle mass and strength may help prevent depression.

The relationship between serum lipid with sarcopenia: Results from the NHANES 2011-2018 and bidirectional Mendelian randomization study

BACKGROUND

The relationship between serum lipids and sarcopenia remains unclear due to conflicting results in previous studies.

OBJECTIVE

To explore the associations and potential causality between serum lipids, including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and total cholesterol (TC), and sarcopenia.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) were analysed using multivariable regression and restricted cubic splines (RCSs) to assess the associations between serum lipids and sarcopenia. Bidirectional Mendelian randomization (MR) was employed to investigate the causal relationships with sarcopenia-related traits such as appendicular lean mass (ALM), hand grip strength, and usual walking pace.

RESULTS

Serum HDL-C and TG levels were inversely associated with ALMBMI, with each 1-unit increase linked to a 0.13 % and 1.32 % decrease, respectively. Elevated TG, but not HDL-C, LDL-C, or TC levels, was significantly associated with an increased risk of sarcopenia (P for trend = 0.001). RCS analysis revealed a log-shaped dose-response relationship between TG and sarcopenia risk (P overall <0.001, P non-linear <0.001), with a cutoff value of 92.75 mg/dL. Genetically predicted HDL-C, LDL-C, and TG were associated with ALM. Conversely, ALM showed an inverse causal relationship with all four serum lipids. Additionally, genetically predicted usual walking pace influenced HDL-C and TG levels (P < 0.001).

CONCLUSION

The study reveals a nonlinear association between TG levels and sarcopenia risk, and a bidirectional association between lipid profiles and muscle mass, underscoring the need for further research to elucidate these mechanisms.

Relationship between aging and excess body fat with markers of inflammation, skeletal muscle mass and strength in Mexican community-dwelling people

INTRODUCTION

Aging is accompanied by changes in body composition, such as an increase in fat mass (FM), a decrease in skeletal muscle mass index (SMMI) and muscle strength, combined with a chronic inflammatory process (CI).

OBJECTIVE

Determine the relationship between age and excess body fat with markers of chronic inflammation, skeletal muscle mass and strength.

METHODS

A cross-sectional alitical study was carried out in a convenience sample of adults 45 to 59 years old (n = 100) and older adults 60 to 74 years old (n = 133). All participants had their body composition measured with an impedance meter. They were subsequently divided into two groups: (i) with excess fat (WEF), (ii) without excess fat (NEF), in order to relate excess fat and age with inflammation, muscle mass and strength.

RESULTS

NEF adults and older adults had similar values of SMMI (9.1 ± 1.5 vs. 8.8 ± 1.3, p > 0.05) and strength (28 ± 8 vs. 27 ± 8.6, p > 0.05). Likewise, WEF adults showed significantly lower values than NEF adults in the SMMI (7.9 ± 0.8 vs. 9.1 ± 1.5, p < 0.05) and strength (28 ± 8 vs. 22 ± 5, p < 0.001). Also, WEF older adults presented significantly lower values in the SMMI (15.9 ± 1.8 vs. 22.8 ± 5.1, p < 0.05) and strength (17.9 ± 4.8 vs. 27 ± 8.6, p < 0.001).

CONCLUSIONS

Our findings suggest that excess fat mass is a risk factor that has a significantly greater influence than aging per se on the index of skeletal muscle mass and strength.

Assessing the role of prognostic nutritional index in predicting outcomes for rectal cancer surgery

BACKGROUND & AIMS

The association of Prognostic Nutritional Index (PNI) with prognosis has been established for various cancer types, including rectal cancer. However, the precise relationship between PNI and body composition characteristics in patients with non-metastatic rectal cancer remain unclear. This study aimed to investigate the impact of PNI on overall survival and disease-free survival in non-metastatic rectal cancer patients undergoing total surgical resection. Additionally, it sought to assess the inflammatory status and body composition in patients across different PNI levels.

METHODS

Patients with non-metastatic rectal cancer who underwent total surgical resection, were consecutively enrolled. PNI was calculated using the formula: PNI = (10 × serum albumin [g/dl]) + (0.005 × lymphocytes/μL). Body composition was assessed using CT-derived measurements and laboratory tests performed at diagnosis were used to calculate inflammatory indices. Univariate and multivariate logistic regression analyses as well as Kaplan-Meier curves were used to determine prognostic values.

RESULTS

A total of 298 patients were included. Patients with low PNI demonstrated significantly reduced overall survival and disease-free survival compared to those with high PNI (Hazard ratio [HR] 1.85; Confidence interval [CI] 1.30-2 0.62; p = 0.001). Moreover, patients with low PNI exhibited heightened systemic inflammatory status and reduced skeletal muscle index, increased muscle radiodensity, as well as a decrease in subcutaneous adipose tissue area, subcutaneous fat index, and low attenuation of both subcutaneous and visceral adipose tissue.

CONCLUSION

The PNI, assessed prior to treatment initiation, serves as a prognostic biomarker for non-metastatic rectal cancer patients undergoing total surgical resection and is linked with both inflammation and alterations in body composition.

Regimen on Dnaja3 haploinsufficiency mediated sarcopenic obesity with imbalanced mitochondrial homeostasis and lipid metabolism

BACKGROUND

Sarcopenic obesity is characterized by excess fat mass and diminished muscular mass/function. DNAJA3, a mitochondrial co-chaperone protein, plays a crucial role in skeletal muscle development. GMI, an immunomodulatory protein, promotes myogenic differentiation through DNAJA3 activation. This study aims to elucidate the physiological effects of muscular Dnaja3 haploinsufficiency on mitochondrial dysfunction and dysregulated lipid metabolism and to assess the efficacy of GMI in rescuing sarcopenic obesity both in vitro and in vivo.

METHODS

We generated mouse strain with Dnaja3 heterozygosity (HSA-Dnaja3f/+) specifically in skeletal muscle. The body weight, body composition, and locomotor activity of WT and HSA-Dnaja3f/+ mice were examined. The isolated skeletal muscles and primary myoblasts from the WT and HSA-Dnaja3f/+ mice, at young or old age, were utilized to study the molecular mechanisms, mitochondrial respiration and ROS level, mitochondrial proteomes, and serological analyses, respectively. To evaluate the therapeutic efficacy of GMI, both short-term and long-term GMI treatment were administrated intraperitoneally to the HSA-Dnaja3f/+ young (4 weeks old) or adult (3 months old) mice for a duration of either 1 or 6 months, respectively.

RESULTS

Muscular Dnaja3 heterozygosity resulted in impaired locomotor activity (P < 0.05), reduced muscular cross-sectional area (P < 0.0001), and up-regulation of lipogenesis (ACC2) and pro-inflammation (STAT3) in skeletal muscles (P < 0.05). Primary myoblasts from the HSA-Dnaja3f/+ mice displayed impaired mitochondrial respiration (P < 0.01) and imbalanced mitochondrial ROS levels. A systemic proteomic analysis of the purified mitochondria from the primary myoblasts was conducted to show the abnormalities in mitochondrial function and fatty acid metabolism (P < 0.0001). At age of 13 to 14 months, the HSA-Dnaja3f/+ mice displayed increased body fat mass (P < 0.001), reduced fat-free mass (P < 0.01), and impaired glucose and insulin tolerance (P < 0.01). The short-term GMI treatment improved locomotor activity (P < 0.01) and down-regulated the protein levels of STAT3 (P < 0.05), ACC2, and mitochondrial respiratory complex III (UQCRC2) (P < 0.01) via DNAJA3 activation. The long-term GMI treatment ameliorated fat mass accumulation, glucose intolerance, and systemic inflammation (AST) (P < 0.05) in skeletal muscle, while enhancing thermogenesis (UCP1) (P < 0.01) in eWAT. GMI treatment promoted myogenesis, enhanced oxygen consumption, and ameliorated STAT3 (P < 0.01) through DNAJA3 activation (P < 0.05) in vitro.

CONCLUSIONS

Muscular Dnaja3 haploinsufficiency dysregulates mitochondrial function and lipid metabolism then leads to sarcopenic obesity. GMI emerges as a therapeutic regimen for sarcopenic obesity treatment through DNAJA3 activation.

Myosteatosis is closely associated with sarcopenia and significantly worse outcomes in patients with cirrhosis

BACKGROUND & AIMS

Sarcopenia and myosteatosis are common in patients with cirrhosis. This study aimed to determine the prevalence of these muscle changes, their interrelations and their prognostic impact over a 12-month period.

METHODS

We conducted a prospective multicentre study involving 433 patients. Sarcopenia and myosteatosis were evaluated using computed tomography scans. The 1-year cumulative incidence of relevant events was assessed by competing risk analysis. We used a Fine-Gray model adjusted for known prognostic factors to evaluate the impact of sarcopenia and myosteatosis on mortality, hospitalization, and liver decompensation.

RESULTS

At enrolment, 166 patients presented with isolated myosteatosis, 36 with isolated sarcopenia, 135 with combined sarcopenia and myosteatosis and 96 patients showed no muscle changes. The 1-year cumulative incidence of death in patients with either sarcopenia and myosteatosis (13.8%) or isolated myosteatosis (13.4%) was over twice that of patients without muscle changes (5.2%) or with isolated sarcopenia (5.6%). The adjusted sub-hazard ratio for death in patients with muscle changes was 1.36 (95% CI 0.99-1.86, p = 0.058). The cumulative incidence of hospitalization was significantly higher in patients with combined sarcopenia and myosteatosis than in patients without muscle changes (adjusted sub-hazard ratio 1.18, 95% CI 1.04-1.35). The cumulative incidence of liver decompensation was greater in patients with combined sarcopenia and myosteatosis (p = 0.018) and those with isolated sarcopenia (p = 0.046) than in patients without muscle changes. Lastly, we found a strong correlation of function tests and frailty scores with the presence of muscle changes.

CONCLUSIONS

Myosteatosis, whether alone or combined with sarcopenia, is highly prevalent in patients with cirrhosis and is associated with significantly worse outcomes. The prognostic role of sarcopenia should always be evaluated in relation to the presence of myosteatosis.

IMPACT AND IMPLICATIONS

This study investigates the prognostic role of muscle changes in patients with cirrhosis. The novelty of this study is its multicentre, prospective nature and the fact that it distinguishes between the impact of individual muscle changes and their combination on prognosis in cirrhosis. This study highlights the prognostic role of myosteatosis, especially when combined with sarcopenia. On the other hand, the relevance of sarcopenia could be mitigated when considered together with myosteatosis. The implication from these findings is that sarcopenia should never be evaluated individually and that myosteatosis may play a dominant role in the prognosis of patients with cirrhosis.

Coexistence of high visceral fat area and sarcopenia is associated with atherosclerotic markers in old-old patients with diabetes: A cross-sectional study

AIMS/INTRODUCTION

To investigate whether sarcopenic obesity is associated with the progression of atherosclerotic lesions in older patients with diabetes and to identify the obesity components of sarcopenic obesity that best reflect atherosclerosis.

MATERIALS AND METHODS

In 118 inpatients aged ≥75 years with diabetes mellitus, sarcopenia defined as a low skeletal muscle mass and low grip strength was assessed, and sarcopenia coexisting with a high body-fat percentage or visceral fat area was defined as sarcopenic obesity. Correlations between the obesity components and atherosclerotic markers, including the carotid intima-media thickness, were analyzed; the intima-media thickness was analyzed in four groups with and without obesity and sarcopenia, and a multiple linear regression analysis adjusted for covariates was conducted to investigate whether sarcopenic obesity was independently associated with the intima-media thickness.

RESULTS

The visceral fat area and intima-media thickness showed positive correlations in the overall patients (P = 0.032) and the sarcopenia (P = 0.016) group but showed no associations in participants without sarcopenia. The intima-media thickness in the group showing sarcopenia with a high visceral fat area was significantly higher than that in the control group (P = 0.012). Sarcopenic obesity defined by a high body-fat percentage and high visceral fat area was independently associated with the intima-media thickness even after adjusting for age, sex, and atherogenic risk factors. However, sarcopenic obesity defined by a high visceral fat area was more strongly associated with the intima-media thickness (β = 0.384, P = 0.002) than that defined by the high body-fat percentage (β = 0.237, P = 0.068).

CONCLUSIONS

Sarcopenic obesity, especially that defined by visceral fat accumulation, reflected the risk of atherosclerotic lesion progression in older patients with diabetes.

Hydrogen sulfide mitigates mitochondrial dysfunction and cellular senescence in diabetic patients: Potential therapeutic applications

Diabetes induces a pro-aging state characterized by an increased abundance of senescent cells in various tissues, heightened chronic inflammation, reduced substance and energy metabolism, and a significant increase in intracellular reactive oxygen species (ROS) levels. This condition leads to mitochondrial dysfunction, including elevated oxidative stress, the accumulation of mitochondrial DNA (mtDNA) damage, mitophagy defects, dysregulation of mitochondrial dynamics, and abnormal energy metabolism. These dysfunctions result in intracellular calcium ion (Ca2+) homeostasis disorders, telomere shortening, immune cell damage, and exacerbated inflammation, accelerating the aging of diabetic cells or tissues. Hydrogen sulfide (H2S), a novel gaseous signaling molecule, plays a crucial role in maintaining mitochondrial function and mitigating the aging process in diabetic cells. This article systematically explores the specific mechanisms by which H2S regulates diabetes-induced mitochondrial dysfunction to delay cellular senescence, offering a promising new strategy for improving diabetes and its complications.

Association Between Weight-Adjusted Waist Index and Albuminuria in Type 2 Diabetes Mellitus in the Chinese Population

Purpose

This study aimed to investigate the relationship between weight-adjusted waist index (WWI) and albuminuria in patients with type 2 diabetes mellitus (T2DM) in the Chinese population.

Patients and Methods

A total of 860 adult patients in the Department of Endocrinology of the Affiliated Hospital of Jiangsu University were retrospectively analyzed from June 2018 to September 2023. Correlations between WWI and albuminuria (albumin-to-creatinine ratio (UACR) ≥ 30 mg/g were defined as albuminuria) were analyzed using the Pearson and Spearman methods. The associations between albuminuria and Age, gender, body mass index (BMI), waist circumference/ hip circumference (WHR), systolic blood pressure(SBP), diastolic blood pressure (DBP), fasting plasma glucose (FPG), 2-hour postprandial plasma glucose (2h PG), fasting plasma insulin (FIns), 2-h postprandial insulin (2hINS), glycosylated hemoglobin (HbA1c), WWI, homeostasis model assessment of insulin resistance (HOMA-IR) were analyzed via binary logistic regression.

Results

Compared with the normal albumin group, serum urea nitrogen, serum creatinine, UACR, and WWI levels in the albuminuria group were significantly increased, while estimated glomerular filtration rate (eGFR) levels were significantly decreased (P < 0.05). Correlation analyses revealed that WWI was positively correlated with UACR but negatively correlated with urea nitrogen, serum creatinine, and eGFR (P < 0.05). Binary logistic regression analyses indicated that WWI was an independent risk factor for albuminuria in T2DM patients. Receiver operating characteristic curve results showed that the area under the curve for albuminuria as predicted by WWI was 0.605 [95% CI = (0.563-0.646), P < 0.001].

Conclusion

WWI is independently associated with albuminuria in the Chinese patients with type 2 diabetes and may serve as a simple indicator for albuminuria risk assessment.

Muscle aging and sarcopenia: The pathology, etiology, and most promising therapeutic targets

Sarcopenia is a progressive muscle wasting disorder that severely impacts the quality of life of elderly individuals. Although the natural aging process primarily causes sarcopenia, it can develop in response to other conditions. Because muscle function is influenced by numerous changes that occur with age, the etiology of sarcopenia remains unclear. However, recent characterizations of the aging muscle transcriptional landscape, signaling pathway disruptions, fiber and extracellular matrix compositions, systemic metabolomic and inflammatory responses, mitochondrial function, and neurological inputs offer insights and hope for future treatments. This review will discuss age-related changes in healthy muscle and our current understanding of how this can deteriorate into sarcopenia. As our elderly population continues to grow, we must understand sarcopenia and find treatments that allow individuals to maintain independence and dignity throughout an extended lifespan.

Strategies for minimizing muscle loss during use of incretin-mimetic drugs for treatment of obesity

The rapid and widespread clinical adoption of highly effective incretin-mimetic drugs (IMDs), particularly semaglutide and tirzepatide, for the treatment of obesity has outpaced the updating of clinical practice guidelines. Consequently, many patients may be at risk for adverse effects and uncertain long-term outcomes related to the use of these drugs. Of emerging concern is the loss of skeletal muscle mass and function that can accompany rapid substantial weight reduction; such losses can lead to reduced functional and metabolic health, weight cycling, compromised quality of life, and other adverse outcomes. Available evidence suggests that clinical trial participants receiving IMDs for the treatment of obesity lost 10% or more of their muscle mass during the 68- to 72-week interventions, approximately equivalent to 20 years of age-related muscle loss. The ability to maintain muscle mass during caloric restriction-induced weight reduction is influenced by two key factors: nutrition and physical exercise. Nutrition therapy should ensure adequate intake and absorption of high-quality protein and micronutrients, which may require the use of oral nutritional supplements. Additionally, concurrent physical activity, especially resistance training, has been shown to effectively minimize loss of muscle mass and function during weight reduction therapy. All patients receiving IMDs for obesity should participate in comprehensive treatment programs emphasizing adequate protein and micronutrient intakes, as well as resistance training, to preserve muscle mass and function, maximize the benefit of IMD therapy, and minimize potential risks.

Bidirectional association between perioperative skeletal muscle and subcutaneous fat in colorectal cancer patients and their prognostic significance

Introduction

Low skeletal muscle mass and high adipose tissue coexist across the body weight spectrum and independently predict the survival ratio of colorectal cancer (CRC) patients. This combination may lead to a mutually exacerbating vicious cycle. Tumor-associated metabolic conditions primarily affect subcutaneous adipose tissue, but the nature and direction of its relationship with skeletal muscle are unclear. This study aims to examine the bidirectional causal relationship between skeletal muscle index (SMI) and subcutaneous fat index (SFI) during the perioperative period in CRC patients; as well as to validate the association between perioperative SMI, SFI, and CRC prognosis.

Methods

This population-based retrospective cohort study included patients with stage I-III colorectal cancer who underwent radical resection at the Third Affiliated Hospital of Kunming Medical University between September 2012 and February 2019. Based on inclusion and exclusion criteria, 1,448 patients were analyzed. Preoperative (P1), 2 months postoperative (P2), and 5 months postoperative (P3) CT scans were collected to evaluate the skeletal muscle index (SMI; muscle area at the third lumbar vertebra divided by height squared) and subcutaneous fat index (SFI; subcutaneous fat area at the third lumbar vertebra divided by height squared). A random intercept cross-lagged panel model (RI-CLPM) was used to examine the intra-individual relationship between SMI and SFI, and Cox regression was employed to assess the association between SMI, SFI, recurrence-free survival (RFS), and overall survival (OS).

Results

The median age at diagnosis was 59.00 years (IQR: 51.00-66.00), and 587 patients (40.54%) were female. RI-CLPM analysis revealed a negative correlation between SFI and subsequent SMI at the individual level: P1-P2 (β = -0.372, p = 0.038) and P2-P3 (β = -0.363, p = 0.001). SMI and SFI showed a negative correlation during P1-P2 (β = -0.363, p = 0.001) but a positive correlation during P2-P3 (β = 0.357, p = 0.006). No significant correlation was found between the random intercepts of SFI and SMI at the between-person level (r = 0.157, p = 0.603). The Cox proportional hazards multivariate regression model identified that patients with elevated SFI had poorer recurrence-free survival (HR, 1.24; 95% CI: 1.00-1.55). Compared to patients with normal preoperative SMI and SFI, those with low SMI or high SFI had poorer recurrence-free survival (HR, 1.26; 95% CI: 1.03-1.55) and overall survival (HR, 1.39; 95% CI: 1.04-1.87). However, no significant association between SMI and SFI and the prognosis of colorectal cancer patients was observed postoperatively.

Conclusion

In CRC patients, preoperative muscle loss leads to postoperative fat accumulation, exacerbating muscle loss in a feedback loop. Elevated preoperative SFI predicts poorer survival outcomes. Monitoring SMI and SFI is crucial as prognostic indicators, despite non-significant postoperative associations. Further research is needed to improve patient outcomes.

Association of visceral adiposity index with sarcopenia based on NHANES data

The Visceral Adiposity Index (VAI) assesses visceral fat and related metabolic risks. However, its precise correlation with sarcopenia is unclear. This study aimed to examine this correlation. A cross-sectional analysis was conducted using NHANES data from 2011 to 2018. To correct VAI skewness, a logarithmic transformation was applied. Multiple covariates were included, and logistic regression was employed to explore the relationship between VAI and sarcopenia. Restricted cubic spline (RCS) and threshold saturation analyses were used to investigate the nonlinear relationship. Subgroup analyses evaluated the effects of various stratification factors. Sensitivity and additive analyses tested the robustness of the findings. The study included 4688 individuals. Participants with sarcopenia had significantly higher VAI values. Logistic regression revealed a significant positive connection between Log VAI and sarcopenia (OR 2.09, 95% CI 1.80-2.43) after adjusting for variables. RCS analysis showed a nonlinear correlation, identifying a breakpoint at VAI = 1.51. To the left of this breakpoint, each unit increase in VAI significantly correlated with a higher likelihood of sarcopenia (OR 2.54, 95% CI 1.74-3.79); to the right, increases in VAI did not significantly affect prevalence. Subgroup analyses suggested VAI as an independent risk factor. Sensitivity and additive analyses confirmed the main findings' robustness. Among American adults, the VAI is significantly associated with sarcopenia, with higher VAI values potentially increasing the prevalence of sarcopenia. Monitoring VAI is critical for early identification of high-risk individuals and interventions to delay or minimize the onset and progression of sarcopenia.

Which factors are associated with acquired weakness in the ICU? An overview of systematic reviews and meta-analyses

RATIONALE

Intensive care unit-acquired weakness (ICUAW) is common in critically ill patients, characterized by muscle weakness and physical function loss. Determining risk factors for ICUAW poses challenges due to variations in assessment methods and limited generalizability of results from specific populations, the existing literature on these risk factors lacks a clear and comprehensive synthesis.

OBJECTIVE

This overview aimed to synthesize risk factors for ICUAW, categorizing its modifiable and nonmodifiable factors.

METHODS

An overview of systematic reviews was conducted. Six relevant databases were searched for systematic reviews. Two pairs of reviewers selected reviews following predefined criteria, where bias was evaluated. Results were qualitatively summarized and an overlap analysis was performed for meta-analyses.

RESULTS

Eighteen systematic reviews were included, comprising 24 risk factors for ICUAW. Meta-analyses were performed for 15 factors, while remaining reviews provided qualitative syntheses. Twelve reviews had low risk of bias, 4 reviews were unclear, and 2 reviews exhibited high risk of bias. The extent of overlap ranged from 0 to 23% for the corrected covered area index. Nonmodifiable factors, including advanced age, female gender, and multiple organ failure, were consistently associated with ICUAW. Modifiable factors, including neuromuscular blocking agents, hyperglycemia, and corticosteroids, yielded conflicting results. Aminoglycosides, renal replacement therapy, and norepinephrine were associated with ICUAW but with high heterogeneity.

CONCLUSIONS

Multiple risk factors associated with ICUAW were identified, warranting consideration in prevention and treatment strategies. Some risk factors have produced conflicting results, and several remain underexplored, emphasizing the ongoing need for personalized studies encompassing all potential contributors to ICUAW development.

The Effect of 8-Week Protein Supplementation with a Simple Exercise Program on Body Composition, Muscle Strength, and Amino Acid OMICS among Healthy Sedentary Indians: A Randomized, Double-Blind, Placebo-Controlled Trial

Dietary protein plays a crucial role in the modulation of several physiological processes to sustain health and well-being. There is robust evidence of enhanced muscle protein synthesis, improved physical fitness, body composition, and performance contributed by protein supplementation combined with exercise among trained individuals or athletes. Evidence of the efficacy of such intervention on healthy adults having a sedentary lifestyle is limited. The objective of this study was to evaluate the impact of 12 g of additional protein in the form of a protein supplement compared to a placebo combined with a simple exercise program on plasma amino acid level, body composition, and muscle strength among healthy Indian adults having a relatively sedentary lifestyle. This double-blinded, randomized controlled trial was conducted on sedentary healthy adults 20-45 years of age, with a body mass index (BMI) between 18.5 and 27.9 kg/m2. Eighty-two participants were randomized into either the protein (intervention) or placebo (control) group. The exercise regime was the same for both groups. Out of 82 randomized participants, 58 completed the intervention. Blood tests were conducted for the amino acid OMICS measurement followed by dual-energy X-ray absorptiometry (DXA) for body composition and isokinetic dynamometry for muscle strength. A significant improvement was observed in the lean mass (kg) and appendicular muscle mass (AMM) adjusted for weight in the intervention group compared to the control group (p < 0.05). The muscle strength and contractile quality were comparable in the 2 groups. Plasma BCAA showed a significant negative association with body fat % (r = -0.43, p < 0.05 for the intervention group and r = -0.33, p = 0.07 for the control group) and a positive association with lean body mass % (r = 0.56, p < 0.01 in the intervention group vs r = 0.29, p = 0.10 in the control group) in the intervention group compared to control. In conclusion, this study highlighted the value of incorporating a lifestyle intervention including protein supplementation with simple exercises to optimize body composition in sedentary healthy individuals. This trial is registered with CTRI/2018/12/016777.

Causal Relationship Between Gut Microbiota, Metabolites, and Sarcopenia: A Mendelian Randomization Study

BACKGROUND

Gut microbiota imbalance and sarcopenia are frequently observed in older adults. Gut microbiota and their metabolites are considered risk factors contributing to the heightened risk of sarcopenia, but whether these associations are causal remains unclear.

METHODS

We conducted linkage disequilibrium score regression and 2-sample Mendelian randomization (MR) methods with single-nucleotide polymorphisms sourced from large-scale genome-wide association studies as instrumental variables to examine the causal associations linking gut microbiota with their metabolites to the sarcopenia. Following the MR analysis, subsequent sensitivity analyses were conducted to reinforce the robustness and credibility of the obtained results.

RESULTS

MR analysis yielded compelling evidence demonstrating the correlation between genetically predicted gut microbiota and metabolites and the risk of sarcopenia. The abundance of Porphyromonadaceae, Rikenellaceae, Terrisporobacter, and Victivallis was found to be associated with walking pace. Our study also found suggestive associations of 12 intestinal bacteria with appendicular lean mass, and of Streptococcaceae, Intestinibacter, Paraprevotella, Ruminococcaceae UCG009, and Sutterella with grip strength. Specifically, we identified 21 gut microbiota-derived metabolites that may be associated with the risk of sarcopenia.

CONCLUSIONS

Utilizing a 2-sample MR approach, our study elucidates the causal interplay among gut microbiota, gut microbiota-derived metabolites, and the occurrence of sarcopenia. These findings suggest that gut microbiota and metabolites may represent a potential underlying risk factor for sarcopenia, and offer the promise of novel therapeutic focal points.

Ultrasound Assessment of Sarcopenia in Alcoholic Liver Disease

Malnutrition frequently affects patients with alcoholic liver disease (ALD), with important impacts on disease prognosis. Sarcopenia, the clinical phenotype of malnutrition characterized by skeletal muscle loss, is the major component responsible for adverse events in this population. The aim of this study is to assess the use of ultrasound (US) skeletal muscle performance in stratifying ALD disease severity. We recruited 43 patients with ALD and divided them into two groups: alcoholic hepatitis (AH) and alcoholic cirrhosis (AC). We evaluated disease-specific clinical and biological parameters and their relation to US Rectus Femoris muscle (RFM) measurements, including RFM thickness, stiffness (RFMS) and echogenicity (RFE). A thirty-seconds chairs stand test (30sCST) was used as the sarcopenia surrogate test. RMF thickness correlated with platelet count and serum albumin (p < 0.001). Both RFM and RFMS correlated with disease severity (p < 0.001) and 30sCST (p < 0.001, p = 0.002). Patients with AH had more severe US muscle abnormalities compared to AC (RFMS 1.78 m/s vs. 1.35 m/s, p = 0.001) and the highest prevalence of RFE (χ2 = 8.652, p = 0.003). Rectus Femoris US assessment could represent a reliable tool in the diagnosis and severity stratification of ALD-induced sarcopenia.

Association of remnant cholesterol with sarcopenia in Korean adults: a nationwide population-based study using data from the KNHANES

Background

Mounting evidence indicates the importance of the interplay between skeletal muscles and lipid metabolism. Remnant cholesterol (remnant-C) is considered one of the principal residual risk factors for cardiovascular disease and metabolic disorders; however, there are limited studies on the impact of remnant-C on sarcopenia.

Methods

Data from the Korea National Health and Nutrition Examination Surveys (KNHANES) between 2008 and 2011 were used in this nationwide population-based study. In total, 17,408 participants were enrolled in this study. The subjects were categorized into four groups according to the quartile of remnant-C values. We conducted multivariable logistic regression analysis to evaluate the association between remnant-C and muscle mass measured using dual-energy X-ray absorptiometry.

Results

A total of 1,791 participants (10.3%) presented low muscle mass, and there was a sequential increase in the percentage of low muscle mass across remnant-C quartiles (Q1, 5.2%; Q2, 8.7%; Q3, 11.5%; Q4, 15.7%). In the full adjusted model, those in the highest remnant-C quartile group showed significantly increased odds ratio (OR) for low muscle mass compared with those in the lowest remnant-C group after adjusting for various confounding factors (OR = 1.33, 95% confidence interval (CI) = 1.06-1.68, P <0.05). A wide range of subgroups and sensitivity analyses showed consistent results, supporting the robustness of our findings.

Conclusions

Increased remnant-C value was associated with a high risk of low muscle mass in the Korean population. Remnant-C may be a novel marker for the prediction and management of sarcopenia in aging societies.

Targeting Crosstalk of Signaling Pathways among Muscles-Bone-Adipose Tissue: A Promising Therapeutic Approach for Sarcopenia

The aging process is associated with the development of a wide range of degenerative disorders in mammals. These diseases are characterized by a progressive decline in function at multiple levels, including the molecular, cellular, tissue, and organismal. Furthermore, it is responsible for various healthcare costs in developing and developed countries. Sarcopenia is the deterioration in the quality and functionality of muscles, which is extremely concerning as it manages many functions in the human body. This article reviews the molecular crosstalk involved in sarcopenia and the specific roles of many mediator molecules in establishing cross-talk between muscles, bone, and fatty tissues, eventually leading to sarcopenia. Besides, the involvement of various etiological factors, such as neurology, endocrinology, lifestyle, etc., makes it exceedingly difficult for clinicians to develop a coherent hypothesis that may lead to the well-organized management system required to battle this debilitating disease. The several hallmarks contributing to the progression of the disease is a vital question that needs to be addressed to ensure an efficient treatment for sarcopenia patients. Also, the intricate molecular mechanism involved in developing this disease requires more studies. The direct relationship of cellular senescence with aging is one of the pivotal issues contributing to disease pathophysiology. Some patented treatment strategies have been discussed, including drugs undergoing clinical trials and emerging options like miRNA and protein-enclosed extracellular vesicles. A clear understanding of the secretome, including the signaling pathways involved between muscles, bone, and fatty tissues, is extremely beneficial for developing novel therapeutics for curing sarcopenia.

Age, sex, and APOE gene-specific associations between dynapenic obesity and dementia in a large cohort

OBJECTIVE

To investigate the associations between dynapenic obesity and the risk of dementia, and the modifying effects of age, sex, and the APOE gene, using a large population-based cohort.

METHODS

279,884 participants aged 55 and above from the UK Biobank were included. The participants were classified into four categories based on body mass index and hand grip strength: healthy, obesity, dynapenia, and dynapenic obesity. The incident dementia was identified based on linked hospital records and death register data. Cox proportional hazards regression models were used to estimate the associations, followed by age-, sex-, and apolipoprotein E (APOE) gene-stratified analyses.

RESULTS

During the median follow-up of 12.4 years, 5,170 (1.8%) participants developed dementia. Compared with the healthy group, participants with dynapenic obesity had 67% higher dementia risk (hazard ratio [HR]: 1.67, 95% confidence interval [CI]: 1.44-1.94). Compared with the healthy group, higher risks of dementia in participants with dynapenic obesity were respectively observed in male (HR: 2.03, 95% CI: 1.65-2.50), younger (<65 years, HR: 1.97, 95% CI: 1.55-2.50), and non-ε4-carrier (HR: 1.97, 95% CI: 1.60-2.44) (all P for interaction <0.05). In participants under 65 years and non-ε4-carrier, those with dynapenic obesity had the highest risk of dementia (HR: 2.63, 95% CI: 1.91-3.62), compared with the healthy group (P for second order interaction = 0.026).

CONCLUSIONS

Dynapenic obesity is associated with increased risks of dementia, especially in participants under 65 years and non-ε4-carrier, suggesting the importance of managing dynapenic obesity in the prevention of cognition-related disorders.

Diagnosis of Sarcopenia and Myosteatosis by Computed Tomography in Patients with Esophagogastric and Pancreatic Cancer

The increase in the global incidence of cancer highlights the need to continue advancing in the techniques of diagnosis and nutritional assessment of cancer patients, given the prognostic and therapeutic impact of nutritional status. In this study, sarcopenia was evaluated as an independent predictor of morbidity and mortality. Data from 45 patients diagnosed with esophagogastric or pancreatic cancer were analyzed. Body composition was determined using computed tomography images, and functionality tests were performed. Sarcopenia was present in 22.2% of the patients, while only 31.1% had correct musculature. A reduction in muscle mass or function was observed in 46.7% of the patients. Likewise, the prevalence of myosteatosis reached 60% of the patients. No significant differences were found with regard to the presence of sarcopenia according to BMI classifications, so it is necessary to evaluate the patient with body composition techniques that include the evaluation of the different muscle and fat compartments. In conclusion, a comprehensive intervention is necessary to improve the detection of sarcopenia/myosteatosis and, in the future, to be able to carry out an approach that improves the quality of life and survival rates of patients.

SIRT1 signaling pathways in sarcopenia: Novel mechanisms and potential therapeutic targets

Sarcopenia is an aging-related skeletal disease characterized by decreased muscle mass, strength, and physical function, severely affecting the quality of life (QoL) of the elderly population. Sirtuin 1 (SIRT1), as a nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases, has been reported to participate in various aging-related signaling pathways and exert protective effect on many human diseases. SIRT1 functioned as an important role in the occurrence and progression of sarcopenia through regulating key pathways related to protein homeostasis, apoptosis, mitochondrial dysfunction, insulin resistance and autophagy in skeletal muscle, including SIRT1/Forkhead Box O (FoxO), AMP-activated protein kinase (AMPK)/SIRT1/nuclear factor κB (NF-κB), SIRT1/p53, AMPK/SIRT1/peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), and SIRT1/live kinase B1 (LKB1)/AMPK pathways. However, the specific mechanisms of these processes have not been fully illuminated. Currently, several SIRT1-mediated interventions on sarcopenia have been preliminarily developed, such as SIRT1 activator polyphenolic compounds, exercising and calorie restriction. In this review, we summarized the predominant mechanisms of SIRT1 involved in sarcopenia and therapeutic modalities targeting the SIRT1 signaling pathways for the prevention and prognosis of sarcopenia.

Obesity-induced tissue alterations resist weight loss: A mechanistic review

Interventions aimed at weight control often have limited effectiveness in combating obesity. This review explores how obesity-induced dysfunction in white (WAT) and brown adipose tissue (BAT), skeletal muscle, and the brain blunt weight loss, leading to retention of stored fat. In obesity, increased adrenergic stimulation and inflammation downregulate β-adrenoreceptors and impair catecholaminergic signalling in adipocytes. This disrupts adrenergic-mediated lipolysis, diminishing lipid oxidation in both white and brown adipocytes, lowering thermogenesis and blunting fat loss. Emerging evidence suggests that WAT fibrosis is associated with worse weight loss outcomes; indeed, limiting collagen and laminin-α4 deposition mitigates WAT accumulation, enhances browning, and protects against high-fat-diet-induced obesity. Obesity compromises mitochondrial oxidative capacity and lipid oxidation in skeletal muscle, impairing its ability to switch between glucose and lipid metabolism in response to varying nutrient levels and exercise. This dysfunctional phenotype in muscle is exacerbated in the presence of obesity-associated sarcopenia. Additionally, obesity suppresses sarcolipin-induced sarcoplasmic reticulum calcium ATPase (SERCA) activation, resulting in reduced oxidative capacity, diminished energy expenditure, and increased adiposity. In the hypothalamus, obesity and overnutrition impair insulin and leptin signalling. This blunts central satiety signals, favouring a shift in energy balance toward energy conservation and body fat retention. Moreover, both obese animals and humans demonstrate impaired dopaminergic signalling and diminished responses to nutrient intake in the striatum, which tend to persist after weight loss. This may result in enduring inclinations toward overeating and a sedentary lifestyle. Collectively, the tissue adaptations described pose significant challenges to effectively achieving and sustaining weight loss in obesity.

RBP4 promotes denervation-induced muscle atrophy through STRA6-dependent pathway

BACKGROUNDS

Fat infiltration of skeletal muscle has been recognized as a common feature of many degenerative muscle disorders. Retinol binding protein 4 (RBP4) is an adipokine that has been demonstrated to be correlated with the presence and severity of sarcopenia in the elderly. However, the exact role and the underlying mechanism of RBP4 in muscle atrophy remains unclear.

METHODS

Denervation-induced muscle atrophy model was constructed in wild-type and RBP4 knockout mice. To modify the expression of RBP4, mice were received intramuscular injection of retinol-free RBP4 (apo-RBP4), retinol-bound RBP4 (holo-RBP4) or oral gavage of RBP4 inhibitor A1120. Holo-RBP4-stimulated C2C12 myotubes were treated with siRNAs or specific inhibitors targeting signalling receptor and transporter of retinol 6 (STRA6)/Janus kinase 2 (JAK2)/Signal transducer and activator of transcription 3 (STAT3) pathway. Fat accumulation, myofibre cross-sectional area, myotube diameter and the expression of muscle atrophy markers and myogenesis markers were analysed.

RESULTS

The expression levels of RBP4 in skeletal muscles were significantly up-regulated more than 2-fold from 7 days and sustained for 28 days after denervation. Immunofluorescence analysis indicated that increased RBP4 was localized in the infiltrated fatty region in denervated skeletal muscles. Knockout of RBP4 alleviated denervation-induced fatty infiltration and muscle atrophy together with decreased expression of atrophy marker Atrogin-1 and MuRF1 as well as increased expression of myogenesis regulators MyoD and MyoG. By contrast, injection of retinol-bound holo-RBP4 aggregated denervation-induced ectopic fat accumulation and muscle atrophy. Consistently, holo-RBP4 stimulation also had a dose-dependent effect on the reduction of C2C12 myotube diameter and myofibre cross-sectional area, as well as on the increase of Atrogin-1and MuRF1 expression and decrease of MyoD and MyoG expression. Mechanistically, holo-RBP4 treatment increased the expression of its membrane receptor STRA6 (>3-fold) and promoted the phosphorylation of downstream JAK2 and STAT3. Inhibition of STRA6/JAK2/STAT3 pathway either by specific siRNAs or inhibitors could decrease the expression of Atrogin-1 and MuRF1 (>50%) and decrease the expression of MyoD and MyoG (>3-fold) in holo-RBP4-treated C2C12 myotube. RBP4 specific pharmacological antagonist A1120 significantly inhibited the activation of STRA6/JAK2/STAT3 pathway, ameliorated ectopic fat infiltration and protected against denervation-induced muscle atrophy (30% increased myofibre cross-sectional area) in mice.

CONCLUSIONS

In conclusion, our data reveal that RBP4 promotes fat infiltration and muscle atrophy through a STRA6-dependent and JAK2/STAT3 pathway-mediated mechanism in denervated skeletal muscle. Our results suggest that lowering RBP4 levels might serve as a promising therapeutic approach for prevention and treatment of muscle atrophy.

Sarcopenic obesity and pre-sarcopenia contribute to frailty in community-dwelling Italian older people: data from the FRASNET study

BACKGROUND

The ageing process is characterized by a change of body composition with an increase of fat mass and a reduction of muscle mass. Above a certain threshold these alterations configure a condition named sarcopenic obesity (SO). SO is associated with physical frailty in Asian and Brazilian populations. SO impacts on physical frailty in other ethnic groups but its influence on general frailty which is multidimensional and includes cognitive, social and physical factors, remain insufficiently explored in the Italian population.

METHODS

Frailty was measured in community dwelling Italian older adults enrolled in the FRASNET study with the frailty index (FI). The FI quantifies frailty as the ratio of the number of present health deficits to the total number of health deficits considered. Regression analyses were performed to assess the association between body composition categories and frailty. Classification and regression tree models were run to evaluate the frailty predictors.

RESULTS

One Thousand One Hundred Fourteen participants of the FRASNET study were included in the present analysis. The sample was composed for the 60.5% by females and its median age was 72 years. The median FI score was 0.11 (IQR 0.07-0.20); 234 individuals (21%) were frail (FI ≥ 0.25). SO (B 0.074, 95% C.I. 0.05-0.1, p < 0.001) and pre-sarcopenia (without obesity B 0.03, 95% C.I, 0.007-0.044, p < 0.001, with obesity B 0.11, 95% C.I. 0.05-0.16, p < 0.001) were associated with frailty. Fat mass percentage predicted frailty in people aged 65-70 years whereas, muscle strength predicted general frailty in people aged 70-81 years.

CONCLUSION

Pre-sarcopenia and SO represent potentially treatable predictors of frailty.

Low muscle mass index is associated with type 2 diabetes risk in a Latin-American population: a cross-sectional study

Objective

Diabetes mellitus is a growing disease with severe complications. Various scores predict the risk of developing this pathology. The amount of muscle mass is associated with insulin resistance, yet there is no established evidence linking muscle mass with diabetes risk. This work aims to study that relationship.

Research methods and procedures

This cross-sectional study included 1,388 employees. The FINDRISC score was used to assess type 2 diabetes risk, and bioimpedance was used for body composition analysis. Appendicular skeletal muscle mass adjusted by body mass index (ASM/BMI) was analyzed. Sociodemographic, clinical and anthropometric measures were evaluated, logistic regression models with sex stratification were conducted and ROC curves were calculated to determine the ability of ASM/BMI index to predict T2D risk.

Results

It was observed that patients with higher ASM/BMI had a lower FINDRISC score in both men and women (p < 0.001). A logistic regression model showed and association between ASM/BMI and diabetes risk in women [OR: 0.000 (0.000-0.900), p = 0.048], but not in men [OR: 0.267 (0.038-1.878), p = 0.185]. However, when the body mass index variable was excluded from the model, an association was found between muscle mass adjusted to BMI and diabetes risk in both men [OR: 0.000 (0.000-0.016), p < 0.001], and women [OR:0.001 (0.000-0.034), p < 0.001]. Other risk factors were having a low level of physical activity, waist circumference, age and sedentary lifestyle. A ROC curve was built and the optimal ASM/BMI cut-of value for predicting T2D risk was 0.82 with a sensitivity of 53.71% and specificity of 69.3% [AUC of 0.665 (0.64-0.69; p < 0.0001)].

Conclusion

When quantifying the risk of type 2 diabetes in both women and men, assessing muscle mass can help detect adult individuals with a high risk of developing type 2 diabetes.

The association between weight-adjusted-waist index and muscle strength in adults: a population-based study

Background

The relationship between the weight-adjusted-waist index (WWI) and grip strength, a crucial marker in assessing sarcopenia, lacks clarity. We aimed to explore the relationship between WWI and muscle strength across genders.

Methods

The cross-sectional study involved adults with complete data on WWI and grip strength from the 2011-2014 National Health and Nutrition Examination Survey. WWI was derived by dividing waist circumference by the square root of weight. Weighted multivariable logistic regression and smooth curve fitting techniques were used to examine the independent association and potential non-linear relationship between WWI and grip strength. A two-piecewise linear regression model was utilized to determine the threshold effect. Additionally, subgroup analyses and interaction tests were conducted.

Results

The study encompassed 9,365 participants, including 4,661 males and 4,704 females. Multivariate logistic regression analysis revealed a negative correlation between WWI and grip strength among males (β = -11.49, 95% CI: -12.38, -10.60, p < 0.001) as well as females (β = -2.53, 95% CI: -2.98, -2.08, p < 0.001). Subgroup analysis showed that the negative correlation of WWI with grip strength remained consistent across various age groups and levels of obesity for both males and females.

Conclusion

An increase in WWI correlates with reduced muscle strength in both males and females. WWI was negatively associated not only with muscle mass but also with muscle strength. WWI may serve as an assessment tool for sarcopenia, but further large-scale studies are needed to clarify causality.

The Relationship Between Remnant Cholesterol and Visceral Adipose Tissue: A National Cross-Sectional Study

The aim of our study is to explore the relationship between remnant cholesterol (RC) levels and visceral adipose tissue (VAT) in the US adult population. This cross-sectional study utilized data from 5301 participants aged 20 to 59 years gathered by the National Health and Nutrition Examination Survey (NHANES). RC was determined by deducting both high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c) from total cholesterol (TC), and VAT was measured using dual-energy X-ray absorptiometry. Visceral obesity is defined as a VAT area ≥ 100 cm2. With increasing quartiles of RC levels, the prevalence of visceral obesity rises (16.51% vs. 36.11% vs. 55.66% vs. 74.48%, p<0.001). After adjusting for confounders, RC levels positively correlate with visceral obesity risk (OR=1.039, 95% CI 1.031-1.048, p<0.001). Additionally, individuals with low LDL-c/high RC and those with high LDL-c/low RC showed 2.908-fold (95% CI 1.995-4.241) and 1.310-fold (95% CI 1.022-1.680) higher risk of visceral obesity, respectively, compared to those with low LDL-c/low RC. Receiver Operating Characteristic (ROC) and Decision Curve Analysis (DCA) show RC's superior predictive ability over other lipid markers. Subgroup analysis showed that the relationship between RC and visceral obesity was more ronounced in those with cardiovascular disease. Smooth curve fitting indicated a nonlinear relationship between RC levels and VAT area. Our study highlights that elevated levels of RC are associated with adverse accumulation of VAT. However, the causal relationship between RC and visceral obesity requires additional investigation.

Difference in Body Composition Patterns between Age Groups in Italian Individuals with Overweight and Obesity: When BMI Becomes a Misleading Tool in Nutritional Settings

Little is known about the changes in body composition (BC) in people with overweight or obesity. The aim of this study was to assess the differences in BC patterns in this population based on gender and age. A total of 2844 Italian adults of mixed gender and a body mass index (BMI) of ≥25 kg/m2 underwent a BC assessment by means of dual-energy X-ray absorptiometry (DXA). The sample was categorized into three age groups: 'young' (20-39 years), 'middle' (40-59 years), and 'older' (60-80 years) adults, after being matched by body weight and BMI. Males showed higher total body fat percentage (BF%) and a lower total lean mass (LM), progressively from the young to the middle to the older age groups, while females showed similar values for these total compartments between the three age groups. However, in both genders, participants in the middle and older groups were more likely to have a higher trunk fat percentage by +1.23% to +4.21%, and lower appendicular lean mass (ALM) by -0.81 kg to -2.63 kg with respect to the young group, indicating expression of major central adiposity and sarcopenia. While our findings underscore the limitations of BMI to detect these differences between age groups, the identification of new tools suitable for this aim is greatly needed in this population. Moreover, further investigation that clarifies the impact of these differences in BC patterns between gender and age groups on health outcomes is also required.

Crosstalk between skeletal muscle ratio and cholesterol metabolism disorders: a cross-section study

BACKGROUND

Dysfunction of cholesterol metabolism may be associated with low skeletal muscle mass.  This study aimed to explore the relationship between skeletal muscle mass and cholesterol metabolic disorders in adults.

METHODS

The data of a total of 5949 people with complete medical history data, biochemical data and body composition analysis were recruited. According to the serum cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL) and nonHDL, the population was divided into a disorder group and a normal group. Independent sample t tests, chi-square tests, Pearson's correlation analyses and binary logistic regression analyses were used to study the effect of body composition on abnormal cholesterol metabolism. According to BMI and sex, the population was divided into different subgroups, and binary logistic regression analysis was used to study the effect of the skeletal mass ratio on cholesteral metabolic disorders in different subgroups.

RESULTS

There were significant differences in sex, alcohol consumption, body weight, BMI, skeletal muscle mass index (SMI) [total skeletal muscle mass (kg)/height 2 (m2)] and skeletal muscle mass ratio (SMR) [total skeletal muscle mass (kg)/weight (kg) *100] between the disorder group (hypercholesterolemia, hyper-LDL, lower-HDL and hyper-nonHDL) and the normal group. Pearson correlation analysis revealed that the SMR was negatively correlated, while the SMI was positively correlated with cholesterol metabolic disorders in both sexes. The overweight group was older and had a greater SMI, abnormal cholesteral metabolism ratio and lower SMR than the normal-weight group. In the normal-weight group, the SMR was an independent protective factor against different kinds of cholesteral metabolic disorders in both sexes, while the SMI was a risk factor. In the overweight subgroup, the protective effect on HDL and nonHDL metabolism remained in the male subgroup but disappeared in the female subgroup. However, the SMI was an independent risk factor for different kinds of cholesteral metabolic disorders in both sexes.

CONCLUSIONS

SMR was an independent protective factor against cholesterol metabolic disorders in both males and females, especially in the normal weight group. SMI was an independent risk factor, especially in the overweight group.

Addressing Post-Acute COVID-19 Syndrome in Cancer Patients, from Visceral Obesity and Myosteatosis to Systemic Inflammation: Implications in Cardio-Onco-Metabolism

Cardiovascular disease and cancer are the two leading causes of morbidity and mortality in the world. The emerging field of cardio-oncology described several shared risk factors that predispose patients to both cardiovascular disease and cancer. Post-acute COVID-19 syndrome is a chronic condition that occurs in many patients who have experienced a SARS-CoV-2 infection, mainly based on chronic fatigue, sedentary lifestyle, cramps, breathing difficulties, and reduced lung performance. Post-acute COVID-19 exposes patients to increased visceral adiposity, insulin resistance, myosteatosis, and white adipose tissue content (surrounded by M1 macrophages and characterized by a Th1/Th17 phenotype), which increases the risk of cardiovascular mortality and cancer recurrence. In this review, the main metabolic affections of post-acute COVID-19 syndrome in cancer patients at low and high risk of cardiomyopathies will be summarized. Furthermore, several non-pharmacological strategies aimed at reducing atherosclerotic and cardiac risk will be provided, especially through anti-inflammatory nutrition with a low insulin and glycemic index, appropriate physical activity, and immune-modulating bioactivities able to reduce visceral obesity and myosteatosis, improving insulin-related signaling and myocardial metabolism.

Intrauterine hyperglycaemia during late gestation caused mitochondrial dysfunction in skeletal muscle of male offspring through CREB/PGC1A signaling

BACKGROUND

Maternal diabetes mellitus can influence the development of offspring. Gestational diabetes mellitus (GDM) creates a short-term intrauterine hyperglycaemic environment in offspring, leading to glucose intolerance in later life, but the long-term effects and specific mechanism involved in skeletal muscle dysfunction in offspring remain to be clarified.

METHODS

Pregnant mice were divided into two groups: The GDM group was intraperitoneally injected with 100 mg/kg streptozotocin on gestational days (GDs) 6.5 and 12.5, while the control (CTR) group was treated with vehicle buffer. Only pregnant mice whose random blood glucose level was higher than 16.8 mmol/L beginning on GD13.5 were regarded as the GDM group. The growth of the offspring was monitored, and the glucose tolerance test was performed at different time points. Body composition analysis and immunohistochemical methods were used to evaluate the development of lean mass at 8 weeks. The exercise capacity and grip strength of the male mouse offspring were assessed at the same period. Transmission electron microscopy was used to observe the morphology inside skeletal muscle at 8 weeks and as a foetus. The genes and proteins associated with mitochondrial biogenesis and oxidative metabolism were investigated. We also coanalyzed RNA sequencing and proteomics data to explore the underlying mechanism. Chromatin immunoprecipitation and bisulfite-converted DNA methylation detection were performed to evaluate this phenomenon.

RESULTS

Short-term intrauterine hyperglycaemia inhibited the growth and reduced the lean mass of male offspring, leading to decreased endurance exercise capacity. The myofiber composition of the tibialis anterior muscle of GDM male offspring became more glycolytic and less oxidative. The morphology and function of mitochondria in the skeletal muscle of GDM male offspring were destroyed, and coanalysis of RNA sequencing and proteomics of foetal skeletal muscle showed that mitochondrial elements and lipid oxidation were consistently impaired. In vivo and in vitro myoblast experiments also demonstrated that high glucose concentrations impeded mitochondrial organisation and function. Importantly, the transcription of genes associated with mitochondrial biogenesis and oxidative metabolism decreased at 8 weeks and during the foetal period. We predicted Ppargc1α as a key upstream regulator with the help of IPA software. The proteins and mRNA levels of Ppargc1α in the skeletal muscle of GDM male offspring were decreased as a foetus (CTR vs. GDM, 1.004 vs. 0.665, p = 0.002), at 6 weeks (1.018 vs. 0.511, p = 0.023) and 8 weeks (1.006 vs. 0.596, p = 0.018). In addition, CREB phosphorylation was inhibited in GDM group, with fewer activated pCREB proteins binding to the CRE element of Ppargc1α (1.042 vs. 0.681, p = 0.037), Pck1 (1.091 vs. 0.432, p = 0.014) and G6pc (1.118 vs. 0.472, p = 0.027), resulting in their decreased transcription. Interestingly, we found that sarcopenia and mitochondrial dysfunction could even be inherited by the next generation.

CONCLUSIONS

Short-term intrauterine hyperglycaemia significantly reduced lean mass in male offspring at 8 weeks, resulting in decreased exercise endurance and metabolic disorders. Disrupted organisation and function of the mitochondria in skeletal muscle were also observed among them. Foetal exposure to hyperglycaemia decreased the ratio of phosphorylated CREB and reduced the transcription of Ppargc1α, which inhibited the transcription of downstream genes involving in mitochondrial biogenesis and oxidative metabolism. Abnormal mitochondria, which might be transmitted through aberrant gametes, were also observed in the F2 generation.

Milk Fat Globule Membrane-Containing Protein Powder Promotes Fitness in Caenorhabditis elegans

Milk-derived peptides and milk fat globule membrane (MFGM) have gained interest as health-promoting food ingredients. However, the mechanisms by which these nutraceuticals modulate the function of biological systems often remain unclear. We utilized Caenorhabditis elegans to elucidate how MFGM-containing protein powder (MProPow), previously used in a clinical trial, affect the physiology of this model organism. Our results demonstrate that MProPow does not affect lifespan but promotes the fitness of the animals. Surprisingly, gene expression analysis revealed that MProPow decreases the expression of genes functioning on innate immunity, which also translates into reduced survival on pathogenic bacteria. One of the innate immunity-associated genes showing reduced expression upon MProPow supplementation is cpr-3, the homolog of human cathepsin B. Interestingly, knockdown of cpr-3 enhances fitness, but not in MProPow-treated animals, suggesting that MProPow contributes to fitness by downregulating the expression of this gene. In summary, this research highlights the value of C. elegans in testing the biological activity of food supplements and nutraceuticals. Furthermore, this study should encourage investigations into whether milk-derived peptides and MFGM mediate their beneficial effects through the modulation of cathepsin B expression in humans.

Skeletal muscle quality predicts overall survival in advanced liver hepatocellular carcinoma treated with SIRT and sorafenib: A subanalysis of the SORAMIC trial

BACKGROUND AND AIMS

Our purpose was to assess the impact of muscle quality on overall survival (OS) in patients with advanced HCC.

METHODS

This is a subanalysis of the SORAMIC trial. Overall, 363 patients were included. The SIRT/Sorafenib treatment group comprised 182 patients and the sorafenib group 181 patients. Myosteatosis was defined as skeletal muscle density (SMD) < 41 HU for patients with a body mass index up to 24.9 kg/m2 and <33 HU for patients with a body mass index ≥25 kg/m2. Albumin-gauge score was calculated as follows: serum albumin (g/dL) × SMD (HU). To assess the impact of muscle quality on clinical variables and OS, a Cox regression model was used. Hazard ratios are presented together with 95 % confidence intervals (95 % CI). Kaplan-Meier curves were used for survival analysis.

RESULTS

In the SIRT/sorafenib cohort, low albumin-gauge score was an independent predictor of worse OS, HR = 1.74, CI 95% (1.16-2.62), p = 0.01. In the sorafenib cohort, muscle quality parameters did not predict OS. In alcohol-induced HCC (n = 129), myosteatosis independently predicted OS, HR = 1.85, CI 95% (1.10; 3.12), p = 0.02. In viral-induced HCC (n = 99), parameters of muscle quality did not predict OS. In patients with NASH/Non-alcoholic fatty liver disease (NAFLD) induced HCC, albumin-gauge score was a strong independent predictor of worse OS in the subgroup undergoing combined treatment with SIRT and sorafenib, HR = 9.86, CI 95% (1.12; 86.5), p = 0.04.

CONCLUSIONS

Myosteatosis predicts independently worse OS in patients with alcohol-induced HCC undergoing combined treatment with SIRT and sorafenib. In patients with NASH/NAFLD induced HCC undergoing treatment with SIRT and sorafenib, albumin-gauge score predicts independently worse OS.

IMPACT AND IMPLICATIONS

Associations between parameters of muscle quality and OS are different in accordance to the treatment strategy and etiology of HCC. These findings highlight the prognostic potential of skeletal muscle quality in patients with advanced HCC.

Association between sleep duration and possible sarcopenia in middle-aged and elderly Chinese individuals: evidence from the China health and retirement longitudinal study

BACKGROUND

Sarcopenia is a common cause of disability in the aging population, and managing sarcopenia is an important step in building intrinsic capacity and promoting healthy aging. A growing body of evidence suggests that sleep deprivation may be a mediator of the development of sarcopenia. The purpose of this study was to explore the longitudinal association between sleep duration and possible sarcopenia using data from a national sample.

METHODS

Two waves of data from the CHARLS database for 2011 and 2015 were used in this study. All possible sarcopenia participants met the Asia Working Group for Sarcopenia 2019 (AWGS 2019) diagnostic criteria. Sleep duration was assessed using a self-report questionnaire, and sleep duration was categorized as short (≤ 6 h), medium (6-8 h), or long (> 8 h) based on previous studies. Longitudinal associations between sleep duration and possible sarcopenia will be calculated by univariate and multifactorial logistic regression analyses and expressed as odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

A total of 5654 individuals participated in the follow-up study, with a prevalence of possible sarcopenia of 53.72% (578) in the short sleep duration group, 38.29% (412) in the medium sleep duration group, and 7.99% (86) in the long sleep duration group. According to the crude model of the second-wave follow-up study, short sleep durations were significantly more strongly associated with possible sarcopenia than were medium and long sleep durations (OR: 1.35, 95% CI: 1.17-1.55, P = 0.000). The association between short sleep duration and possible sarcopenia was maintained even after adjustment for covariates such as age, gender, residence, education level, BMI, smoking status, alcohol consumption and comorbidities (OR: 1.18, 95% CI: 1.02-1.36, P = 0.029). In the subgroup analysis, short sleep duration was associated with low grip strength (OR: 1.20, 95% CI: 1.02-1.41, P = 0.031).

CONCLUSIONS

Sleep deprivation may be closely associated with the development of possible sarcopenia in middle-aged and elderly people, which provides new insights and ideas for sarcopenia intervention, and further studies are needed to reveal the underlying mechanisms involved.

Natural Compounds for Preventing Age-Related Diseases and Cancers

Aging is a multifaceted process influenced by hereditary factors, lifestyle, and environmental elements. As time progresses, the human body experiences degenerative changes in major functions. The external and internal signs of aging manifest in various ways, including skin dryness, wrinkles, musculoskeletal disorders, cardiovascular diseases, diabetes, neurodegenerative disorders, and cancer. Additionally, cancer, like aging, is a complex disease that arises from the accumulation of various genetic and epigenetic alterations. Circadian clock dysregulation has recently been identified as an important risk factor for aging and cancer development. Natural compounds and herbal medicines have gained significant attention for their potential in preventing age-related diseases and inhibiting cancer progression. These compounds demonstrate antioxidant, anti-inflammatory, anti-proliferative, pro-apoptotic, anti-metastatic, and anti-angiogenic effects as well as circadian clock regulation. This review explores age-related diseases, cancers, and the potential of specific natural compounds in targeting the key features of these conditions.

Sarcopenia, sarcopenic obesity and the clinical outcome of the older inpatients with COVID-19 infection: a prospective observational study

OBJECTIVE

We aimed to investigate the impact of sarcopenia and sarcopenic obesity (SO) on the clinical outcome in older patients with COVID-19 infection and chronic disease.

METHODS

We prospectively collected data from patients admitted to Huadong Hospital for COVID-19 infection between November 1, 2022, and January 31, 2023. These patients were included from a previously established comprehensive geriatric assessment (CGA) cohort. We collected information on their pre-admission condition regarding sarcopenia, SO, and malnutrition, as well as their medical treatment. The primary endpoint was the incidence of intubation, while secondary endpoints included in-hospital mortality rates. We then utilized Kaplan-Meier (K-M) survival curves and the log-rank tests to compare the clinical outcomes related to intubation or death, assessing the impact of sarcopenia and SO on patient clinical outcomes.

RESULTS

A total of 113 patients (age 89.6 ± 7.0 years) were included in the study. Among them, 51 patients had sarcopenia and 39 had SO prior to hospitalization. Intubation was required for 6 patients without sarcopenia (9.7%) and for 18 sarcopenia patients (35.3%), with 16 of these being SO patients (41%). Mortality occurred in 2 patients without sarcopenia (3.3%) and in 13 sarcopenia patients (25.5%), of which 11 were SO patients (28%). Upon further analysis, patients with SO exhibited significantly elevated risks for both intubation (Hazard Ratio [HR] 7.43, 95% Confidence Interval [CI] 1.26-43.90, P < 0.001) and mortality (HR 6.54, 95% CI 1.09-39.38, P < 0.001) after adjusting for confounding factors.

CONCLUSIONS

The prevalence of sarcopenia or SO was high among senior inpatients, and both conditions were found to have a significant negative impact on the clinical outcomes of COVID-19 infection. Therefore, it is essential to regularly assess and intervene in these conditions at the earliest stage possible.

The role of sarcopenic obesity for the prediction of prognosis of patients with gastrointestinal cancer

BACKGROUND

Sarcopenic obesity (SO) in patients with gastrointestinal cancer is associated with a poor prognosis. We aimed to investigate the prognostic impact of SO in patients with gastrointestinal cancer, as well as the diagnostic cut-off value of SO in patients with gastrointestinal cancer among Chinese population.

METHODS

We conducted a consecutive cohort study. Between January 2017 and January 2019, 289 patients diagnosed with gastrointestinal cancer were included in our study. Skeletal muscle area, total fat area, and subcutaneous fat area were measured by CT scan. All patients were followed up for 5 years. Receiver operating characteristic curves (ROC) were adopted to determine the cut-off values of visceral fat obesity for the prediction of sarcopenia. Based on the cut-off values, patients with sarcopenia combined with visceral fat obesity were divided into the SO group, and the others were divided into the non-sarcopenic obesity (NSO) group. Kaplan-Meier curves and univariate and multivariate Cox proportional hazard models were employed to explore the associations of body composition profiles with 5-year overall survival and disease-specific survival.

RESULTS

Obtained from Youden's Index for ROC for the prediction of 5-year survival, skeletal muscle mass index (SMI) ≤40.02 cm2/m2 with VFA ≥ 126.30 cm2 in men and SMI ≤32.05 cm2/m2 with VFA ≥72.42 cm2 in women indicate a risk of poor prognosis in patients diagnosed with gastrointestinal cancer. Patients with SO had poorer 5-year overall survival (OS) than patients with NSO (6.74% vs. 82.84%, p < 0.001), and poorer 5-year DFS (6.74% vs. 81.82%, p < 0.001). In multivariate analysis, we found that the long-term mortality risk was approximately 13-fold higher among patients in the SO group compared to those with no conditions.

CONCLUSIONS

Preoperative assessment of SO is useful not only for monitoring nutritional status but also for predicting 5-year OS in gastrointestinal cancer patients.

Low dietary vitamin C intake is associated with low muscle strength among elderly Korean women

Although vitamin C is one of the most important antioxidants, its effect on muscle quality is not fully understood. Therefore, we hypothesized that low dietary vitamin C intake is associated with low muscle strength. To test the hypothesis, a single 24-h dietary recall and handgrip strength test of 10,883 younger adults 19-64 y and 3,961 older adults ≥65 y from the seventh Korea National Health and Examination Survey (KNHANES VII 2016-2018) was analyzed by multivariable linear and logistic regression models, and low muscle strength was defined as handgrip strength <28 kg for men and <18 kg for women. Approximately 15.5% of Korean adults met the recommended intake of dietary vitamin C, and those with higher dietary vitamin C intake had higher total energy and protein intake. After adjusting for confounding variables, including age, body mass index, total energy intake, household income, alcohol consumption, smoking, resistance exercise, medical condition, and dietary intake of protein, vitamin E, and β-carotene, dietary vitamin C was correlated with maximal handgrip strength in younger women 19-64 y (β = 0.002; SE = 0.001; P-value = .026) and older women ≥65 y (β = 0.005; SE = 0.002; P-value = .013). Among older women ≥65 y, those in the lowest quartile of dietary vitamin C intake had a higher risk of low muscle strength compared to those in the highest quartile after adjustment of confounding factors (odds ratio, 2.16; 95% confidence interval, 1.49-3.15). These results imply that adequate dietary vitamin C intake may reduce the risk of sarcopenia in older Korean women.

Fatty infiltration in the musculoskeletal system: pathological mechanisms and clinical implications

Fatty infiltration denotes the anomalous accrual of adipocytes in non-adipose tissue, thereby generating toxic substances with the capacity to impede the ordinary physiological functions of various organs. With aging, the musculoskeletal system undergoes pronounced degenerative alterations, prompting heightened scrutiny regarding the contributory role of fatty infiltration in its pathophysiology. Several studies have demonstrated that fatty infiltration affects the normal metabolism of the musculoskeletal system, leading to substantial tissue damage. Nevertheless, a definitive and universally accepted generalization concerning the comprehensive effects of fatty infiltration on the musculoskeletal system remains elusive. As a result, this review summarizes the characteristics of different types of adipose tissue, the pathological mechanisms associated with fatty infiltration in bone, muscle, and the entirety of the musculoskeletal system, examines relevant clinical diseases, and explores potential therapeutic modalities. This review is intended to give researchers a better understanding of fatty infiltration and to contribute new ideas to the prevention and treatment of clinical musculoskeletal diseases.

Importance of Assessing Sarcopenia in Patients with Type 2 Diabetes Mellitus Based on Body Fat Percentage Measured by Dual-Energy X-Ray Absorptiometry in Different Genders

Background

Growing evidence indicates that there is a close relationship between type 2 diabetes mellitus (T2DM) and sarcopenia, and T2DM patients are often accompanied by obesity. However, research exploring the connection between body fat percentage (BFP) and sarcopenia is currently limited.

Methods

This was a cross-sectional study that included 676 patients with T2DM over 50 years old. The appendicular skeletal muscle mass index (ASMI), handgrip strength, and 5-time chair stand test (5-TCST) were measured, and sarcopenia was diagnosed according to the Asian Working Group on Sarcopenia (AWGS). Spearman's coefficient was used to evaluate the correlation of BFP and body mass index (BMI) with the diagnostic elements of sarcopenia, and BFP and other relevant covariates were included in the binary logistic regression model. The subgroup performed an interaction test for statistically significant population baseline information.

Results

The prevalence of sarcopenia was 18.0% in males and 11.6% in females. Spearman correlation analysis showed that BFP was positively correlated with ASMI in women (R=0.107, P=0.029), but not in men. BFP was negatively correlated with grip strength (male: R= -0.187, P=0.003; female: R=-0.108, P=0.029). There was a positive correlation between BFP and 5-TCST (male: R=0.199, P=0.001; female: R=0.144, P=0.003). After adjusting for confounding factors, BFP was an independent risk factor for sarcopenia (men, OR: 1.33, 95% CI: 1.15-1.54; women, OR: 1.26, 95% CI: 1.13-1.41). This correlation was generally consistent, as demonstrated in further subgroup analyses.

Conclusion

High BFP was significantly associated with sarcopenia risk, and this association was independent of gender, age, and BMI.

Association of myosteatosis with short-term outcomes in patients with acute-on-chronic liver failure

Sarcopenia (low muscle mass, i.e., quantity) is associated with poor clinical outcomes in patients with acute-on-chronic liver failure (ACLF). In this study, we aimed to illustrate the clinical prognostic value of myosteatosis (muscle fat infiltration) for short-term mortality in patients with ACLF. We retrospectively enrolled consecutive patients with ACLF between January 2019 and January 2022. Computed tomography-based body composition analysis was performed at the third lumbar vertebral level to determine skeletal muscle radiation attenuation. Fine and Gray's competing risk regression model, with liver transplantation as a competing risk, was used to assess the factors associated with 90-day mortality. A total of 431 patients with ACLF were included. Myosteatosis and sarcopenia were observed in 261 (60.6%) and 87 (20.2%) patients, respectively. Competitive risk regression showed that age (HR 1.021, 95% CI 1.000-1.043, P = 0.042), APASL ACLF Research Consortium (AARC) score (HR 1.498, 95% CI 1.312-1.710, P < 0.001), and sarcopenia (HR 1.802, 95% CI 1.062-3.060, P = 0.029) were independently associated with increased 90-day mortality. Subgroup analysis of male patients with HBV-ACLF revealed that myosteatosis (HR 2.119, 95% CI 1.101-4.078, P = 0.025) was promising prognostic factors for 90-day mortality after being adjusted for ascites, acute kidney injury, AARC score, and sarcopenia. Myosteatosis is predictive of short-term outcomes in male patients with HBV-ACLF. Our results emphasise the importance of focusing on muscle fat infiltration in patients with HBV-ACLF. Further studies are warranted to investigate the underlying mechanisms and potential therapies for myosteatosis.

Bidirectional Association between Sarcopenia and Depressive Symptoms among Chinese Middle- and Older-Aged Adults: Longitudinal Observational Study

BACKGROUND

The study aimed to examine the bidirectional relationship between sarcopenia and depressive symptoms in a national, community-based cohort study, despite the unclear temporal sequence demonstrated previously.

METHODS

Data were derived from four waves (2011 baseline and 2013, 2015, and 2018 follow-ups) of the China Health and Retirement Longitudinal Study (CHARLS). A total of 17,708 participants aged 45 years or older who had baseline data on both sarcopenia status and depressive symptoms in 2011 were included in the study. For the two cohort analyses, a total of 8092 adults without depressive symptoms and 11,292 participants without sarcopenia in 2011 were included. Sarcopenia status was defined according to the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria. Depressive symptoms were defined as a score of 20 or higher on the 10-item Center for Epidemiologic Studies Depressive Scale (CES-D-10). Cox proportional hazard regression models were conducted to examine the risk of depressive symptoms and sarcopenia risk, while cross-lagged panel models were used to examine the temporal sequence between depressive symptoms and sarcopenia over time.

RESULTS

During a total of 48,305.1 person-years follow-up, 1262 cases of incident depressive symptoms were identified. Sarcopenia exhibited a dose-response relationship with a higher risk of depressive symptoms (HR = 1.7, 95%CI: 1.2-2.3 for sarcopenia, and HR = 1.5, 95%CI: 1.2-1.8 for possible sarcopenia, p trend < 0.001). In the second cohort analysis, 240 incident sarcopenia cases were identified over 39,621.1 person-years. Depressive symptoms (HR = 1.5, 95%CI: 1.2-2.0) are significantly associated with a higher risk of developing sarcopenia after multivariable adjustment (p < 0.001, Cross-lagged panel analyses demonstrated that depressive symptoms were associated with subsequent sarcopenia (β = 0.003, p < 0.001). Simultaneously, baseline sarcopenia was also associated with subsequent depressive symptoms (β = 0.428, p < 0.001).

CONCLUSION

This study identified a bidirectional relationship between depressive symptoms and sarcopenia. It seems more probable that baseline sarcopenia is associated with subsequent depressive symptoms in a stronger pattern than the reverse pathway. The interlinkage indicated that maintaining normal muscle mass and strength may serve as a crucial intervention strategy for alleviating mood disorders.

The diagnostic agreement of sarcopenic obesity with different definitions in Chinese community-dwelling middle-aged and older adults

Background

In 2022, the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) launched a consensus on the diagnostic methods for sarcopenic obesity (SO). The study aimed to identify the prevalence and diagnostic agreement of SO using different diagnostic methods in a cohort of subjects from West China aged at least 50 years old.

Methods

A large multi-ethnic sample of 4,155 participants from the West China Health and Aging Trend (WCHAT) study was analyzed. SO was defined according to the newly published consensus of the ESPEN/EASO. Furthermore, SO was diagnosed as a combination of sarcopenia and obesity. The criteria established by the Asian Working Group for Sarcopenia 2019 (AWGS2019) were used to define sarcopenia. Obesity was defined by four widely used indicators: percent of body fat (PBF), visceral fat area (VFA), waist circumference (WC), and body mass index (BMI). Cohen's kappa was used to analyze the diagnostic agreement of the above five diagnostic methods.

Results

A total of 4,155 participants were part of the study, including 1,499 men (63.76 ± 8.23 years) and 2,656 women (61.61 ± 8.20 years). The prevalence of SO was 0.63-7.22% with different diagnostic methods. The diagnosis agreement of five diagnostic methods was poor-to-good (κ: 0.06-0.67). The consensus by the ESPEN/EASO had the poorest agreement with other methods (κ: 0.06-0.32). AWGS+VFA had the best agreement with AWGS+WC (κ = 0.67), and consensus by the ESPEN/EASO had the best agreement with AWGS+ PBF (κ = 0.32).

Conclusion

The prevalence and diagnostic agreement of SO varies considerably between different diagnostic methods. AWGS+WC has the highest diagnostic rate in the diagnosis of SO, whereas AWGS+BMI has the lowest. AWGS+VFA has a relatively good diagnostic agreement with other diagnostic methods, while the consensus of the ESPEN/EASO has a poor diagnostic agreement. AWGS+PBF may be suitable for the alternative diagnosis of the 2022 ESPEN/EASO.

Study on the mechanism of vitamin E alleviating non-alcoholic fatty liver function based on non-targeted metabolomics analysis in rats

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. Vitamin E (VE) has antioxidant properties and can mediate lipid metabolism. Non-targeted metabolomics technology was employed to uncover comprehensively the metabolome of VE in NAFLD rats. NAFLD model was created with a high-fat and high-cholesterol diet (HFD) in rats. NAFLD rats in the VE group were given 75 mg/(kg day) VE. The metabolites in the serum of rats were identified via UPLC and Q-TOF/MS analysis. KEGG was applied for the pathway enrichment. VE improved the liver function, lipid metabolism, and oxidative stress in NAFLD rats induced by HFD. Based on the metabolite profile data, 132 differential metabolites were identified between VE group and the HFD group, mainly including pyridoxamine, betaine, and bretylium. According to the KEGG results, biosynthesis of cofactors was a key metabolic pathway of VE in NAFLD rats. VE can alleviate NAFLD induced by HFD, and the underlying mechanism is associated with the biosynthesis of cofactors, mainly including pyridoxine and betaine.

Targeting obesity for therapeutic intervention in heart failure patients

INTRODUCTION

Heart failure with preserved ejection fraction (HFpEF) is a highly heterogeneous syndrome, making it challenging to improve prognosis with pharmacotherapy. Obesity is one of the leading phenotypes of HFpEF, and its prevalence continues to grow worldwide. Consequently, obesity-targeted interventions have attracted attention as a novel treatment strategy for HFpEF.

AREAS COVERED

The authors review the association between the pathogenesis of obesity and HFpEF and the potential for obesity-targeted pharmacotherapeutic strategies in HFpEF, together with the latest evidence. The literature search was conducted in PubMed up to April 2024.

EXPERT OPINION

The STEP HFpEF (Semaglutide Treatment Effect in People with obesity and HFpEF) and SELECT (Semaglutide Effects on Cardiovascular Outcomes in People with Overweight or Obesity) trials recently demonstrated that the glucagon-like peptide 1 analogue, semaglutide, improves various aspects of clinical outcomes in obese HFpEF patients and significantly reduces cardiovascular and heart failure events in non-diabetic obese patients, along with a substantial weight loss. Future clinical trials with other incretin mimetics with more potent weight loss and sub-analyses of the SELECT trial may further emphasize the importance of the obesity phenotype-based approach in the treatment of HFpEF.

Albumin-myosteatosis gauge as a prognostic factor in patients with advanced pancreatic cancer undergoing first-line chemotherapy

BACKGROUND

Sarcopenia and myosteatosis have been associated with a poor prognosis for several cancers. The albumin-myosteatosis gauge (AMG) is a novel integrated measure proposed to assess myosteatosis along with serum albumin level as a surrogate of systemic inflammation and malnutrition. The aim of this study was to investigate the prognostic value of AMG in patients with advanced pancreatic ductal adenocarcinoma (PDAC).

METHODS

Patients with advanced PDAC treated with chemotherapy between 2013 and 2022 were evaluated. Skeletal muscle radiodensity (SMD) and skeletal muscle index (SMI) were calculated using computed tomography at the level of the L3 vertebra. The AMG was defined as albumin x SMD and expressed as an arbitrary unit (AU). Patients were first categorized by sex-specific quartiles and then dichotomized at the sex-specific median value of the AMG.

RESULTS

A total of 196 patients were included. The median age (interquartile range) was 62 (54-67), and 128 (65.3%) were male. With regard to AMG, 142.86 and 114.15 AU were identified as cutoff values for males and females, respectively. In multivariable analyses, lower AMG values (G1-G2 vs. G3-G4) (HR: 1.61, 95% CI 1.17-2.21, p = 0.003), higher ECOG performance score (> 0 vs. 0) (HR: 1.51, 95% CI 1.10-2.06, p = 0.009) and metastatic disease (vs. locally advanced) (HR: 1.88, 95% CI 1.27-2.79, p = 0.001) were associated with OS.

CONCLUSION

The study findings suggest the prognostic value of AMG in patients with advanced PDAC undergoing first-line chemotherapy. Further studies are warranted to validate these findings and assess potential predictive role of AMG in guiding treatment selection.

Skeletal muscle mass increases after viral eradication with direct-acting antivirals in patients with chronic hepatitis C: A longitudinal study

BACKGROUND

Results of studies evaluating the effect of viral eradication following direct-acting antiviral (DDA) therapy on skeletal muscle mass of patients with chronic hepatitis C (CHC) are scarce.

AIM

To assess the components of sarcopenia (low muscle mass, low muscle strength and low physical performance) in a cohort of CHC individuals before and after DAA therapy.

METHODS

We performed a longitudinal study of patients with CHC who underwent body composition assessment before (T0), and at 12 (T1) and 48 (T2) weeks after DDA therapy. Bioelectrical Impedance Analysis was used to assess skeletal mass muscle (SM) and phase angle (PhA). SM index (SMI) was calculated by dividing the SM by squared height. Muscle function was evaluated by hand grip strength (HGS) and timed up-and-go (TUG) test. Mixed-effects linear regression models were fitted to SMI, HGS and physical performance and were used to test the effect of HCV eradication by DAA.

RESULTS

62 outpatients (mean age, 58.6 ± 10.8 years; 58% with compensated cirrhosis) were included. Significant decreases in liver fibrosis markers and an increase of 0.20 and 0.22 kg/m2 in the SMI were observed at T1 and T2. Following DAA therapy, an increase of one unit of PhA was associated with a reduction of 0.38 min in TUG.

CONCLUSION

HCV eradication with DAA therapy was associated with a dynamic reduction of non-invasive markers of liver fibrosis and increased muscle mass in 62 patients with CHC who had an undetectable HCV load at 12 weeks after completion of antiviral treatment.