Lipoprotein subfractions in patients with sarcopenia and their relevance to skeletal muscle mass and function

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.

Association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and sarcopenia in individuals with cancer: a cross-sectional study

BACKGROUND

Cancer and sarcopenia are both closely related to lipid metabolism, but the relationship between lipid metabolism and patients with cancer and sarcopenia has not been thoroughly studied. The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) is a reliable measure of lipid metabolism. The purpose of this study was to determine the possible relationship between the NHHR and sarcopenia in individuals with cancer.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) database for individuals with cancer, with and without sarcopenia was analyzed using weighted multiple regression equations, weighted regression cubic spline (RCS) analysis, and weighted subgroup analysis.

RESULTS

In total, 1,602 individuals with cancer were included, of whom 17.1% had sarcopenia. In Adjusted Model 2, the occurrence of sarcopenia was found to be significantly associated with a higher NHHR in cancer (95% confidence interval [CI]:1.01-1.39, P = 0.036). Individuals with high a NHHR had a 2.09-fold higher risk of developing sarcopenia in comparison to those with a low NHHR (95% CI:1.12-3.92, P = 0.022). RCS analysis further identified a U-shaped non-linear relationship between females with cancer and the muscle index. Subgroup analysis indicated that sex was a significant stratifying factor, whereas age, race, marital status, smoking and drinking habits, and history of cardiovascular disease, arthritis, hypertension, and diabetes had no significant impact.

CONCLUSION

From the perspective of lipid metabolism, the NHHR may serve as an indicator for monitoring and preventing the occurrence of sarcopenia in individuals with cancer, particularly for females with cancer who appear to have greater sensitivity.

Impact of CT-relevant skeletal muscle parameters on post-liver transplantation survival in patients with hepatocellular carcinoma

BACKGROUND

The specific CT-related skeletal muscle parameters predictive of postoperative survival in liver transplant (LT) patients with hepatocellular carcinoma (HCC) remain unclear. There is increasing evidence supporting the role of fatty acids and their lipid intermediates in regulating skeletal muscle mass and function, the relationship between lipoprotein subfractions and body composition remains unclear.

METHODS

Adult patients with HCC who underwent LT between January 2015 and September 2022 were retrospectively analyzed. CT parameters, including skeletal muscle index (SMI), psoas muscle index (PMI), skeletal muscle density (SMD), visceral and subcutaneous adipose tissue (VAT and SAT), and the VAT/SAT ratio at the L3 level, and lipid profiles, were assessed prior to LT.

RESULTS

Of the 284 LT patients with HCC, 224 underwent CT (L3 level) within 3 months of LT, and 82 (37%) were diagnosed with myosteatosis. Patients with myosteatosis exhibited significantly lower 1- and 3-year survival rates (p = 0.002, p = 0.01), a trend persisting even beyond the Milan criteria (p = 0.004, p = 0.04). After adjusting for covariates, SMD demonstrated a significant negative correlation with post-transplant survival (HR: 0.90, [95% Confidence Interval(CI): 0.83-0.98], C-statistic: 0.78, p = 0.009). Pearson's correlation analysis revealed a positive correlation between high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A1(ApoA1) levels and SMD. Multivariate stepwise regression analysis demonstrated that every 10 Hounsfield unit decrease in SMD was associated with a 0.16 mmol/L decrease in HDL-C and a 0.18 g/L decrease in ApoA1.

CONCLUSION

Routine abdominal CT scans for assessing skeletal muscle density before LT were significantly associated with post-transplant mortality. Furthermore, abnormal HDL-C and ApoA1 levels before LT were associated with myosteatosis.

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.

Relationships Between the Apolipoprotein Levels and Sarcopenia in Inpatients with Type 2 Diabetes Mellitus: A Cross-Sectional Study

Background

Apolipoprotein (Apo) may be associated with sarcopenia in elderly inpatients with type 2 diabetes mellitus (T2DM), but fewer studies are available. In this study, we explored the association of ApoA1, ApoB, and ApoB/ApoA1 with sarcopenia and compared the predictive role of Apo indicators for sarcopenia in an elderly T2DM.

Objective

To investigate the relationships between the Apo and sarcopenia in elderly inpatients with T2DM.

Methods

This study included 253 inpatients with T2DM (mean age of 70.11±5.44 years, 32.8% male). The inpatients were divided into the sarcopenic group (n = 100) and non-sarcopenic group (n = 153). The associations among the Apo and sarcopenia were assessed using multivariate analyses.

Results

Inpatients in the sarcopenia group showed lower ApoA1 levels than those in the non-sarcopenia group (1.25±0.21 vs 1.36±0.20 g/L, P < 0.05) and showed higher ApoB/ApoA1 and ApoB levels than those in the non-sarcopenia group (0.82±0.27 vs 0.69±0.19 g/L, P < 0.05;1.00±0.32 vs 0.93±0.24 g/L, P < 0.05, respectively). After adjusting for age and BMI, the logistic regression model indicated that ApoA1 was a protective factor for elderly inpatients with T2DM sarcopenia.(OR =0.079,95% CI: 0.021~0.306, P < 0.05);ApoB and AopB/AopA1 were risk factors for elderly inpatients with T2DM sarcopenia.(OR =3.578,95% CI:1.318~9.715, P < 0.05;OR =16.440,95% CI:4.437~60.427, P < 0.05, respectively). AopB/AopA1 provided an AUC value of 0.765 in elderly men.(95% CI: 0.665~0.866, P<0.05).

Conclusion

ApoA1, AopB, and AopB/AopA1 are associated with sarcopenia in elderly inpatients with T2DM, and AopB/AopA1 may be a potential predictor of sarcopenia in elderly men with T2DM.

Correlation between low handgrip strength and metabolic syndrome in older adults: a systematic review

Muscle weakness has been associated to insulin resistance and metabolic syndrome in the general population. However, it is still unclear whether this association is maintained in older adults. This study investigated correlations between low handgrip strength (HGS) and metabolic syndrome, or some of its components, in older adults through a systematic review of the literature. Searches were conducted in the Virtual Health Library Regional Portal, Scopus, Cochrane, Embase, MEDLINE/ PubMed, SciELO, and Web of Science databases for relevant studiesinvestigating muscle weakness (measured by hand dynamometer) and metabolic syndrome or its components in older adult populations, published up to September 2023. From the 2050 references initially identified, 20 studies, comprising a total of 31,264 older adults of both genders, completely met the inclusion/exclusion criteria. Eighteen studies showed that lower HGS was associated with metabolic syndrome or some of its risk factors, such as abdominal obesity, hyperglycemia, insulin resistance, dyslipidemia, or high blood pressure. Two studies found that older men with high blood pressure had increased HGS. Most studies included in this systematic review revealed a significant correlation between reduced HGS and metabolic syndrome or some of its components, especially abdominal obesity and insulin resistance. We conclude that below-average HGS can be associated with metabolic syndrome in older adults.

Lipid-Lowering Medications are Associated with Reduced Sarcopenia-Related Quality of Life in Older Adults with Hyperlipidemia

PURPOSE

Statins medications negatively affect age-associated loss of muscle mass and strength, termed sarcopenia, and neuromuscular junction (NMJ) integrity. However, their association with the sarcopenia-related-quality-of-life (SarQoL) is unknown.

METHODS

In this cross-sectional, case control study, we recruited male nonusers (n = 75 and age 75.2 ± 5.9 years) and users (n = 77 and age 77.1 ± 6.2 years) of statins to evaluate SarQoL and handgrip strength (HGS). We also measured plasma C-terminal agrin fragment-22 (CAF22) as a marker of NMJ degradation.

RESULTS

Statin users had higher CAF22, and lower HGS, and cumulative SarQoL scores than non-users (all p < 0.05). Plasma CAF22 exhibited negative correlations with SarQoL scores for physical and mental health, locomotion, functionality, activities-of-daily-living, and cumulative SarQoL in statins users and non-users (all p < 0.05). Lastly, the cumulative SarQoL scores exhibited positive associations with HGS and gait speed in the study participants (all p < 0.05).

CONCLUSIONS

Collectively, statin usage was associated with NMJ degradation and reduced SarQoL. Statins should be cautiously prescribed in patients with sarcopenia with reduced QoL.

Relationship between sarcopenia and fatty liver in middle-aged and elderly patients with type 2 diabetes mellitus

OBJECTIVE

In this study, we investigated the relationship between sarcopenia and fatty liver in middle-aged and elderly patients diagnosed with type 2 diabetes mellitus (T2DM) to provide a theoretical foundation for the prevention and treatment of sarcopenia.

METHODS

A total of 282 patients diagnosed with T2DM aged 50 and older and were admitted to the Endocrinology Department of Xin Medical University First Affiliated Hospital between December 2021 and February 2023, were selected. Body mass index (BMI), and limb and trunk muscle mass of the patients were measured, and data were collected. Patients were grouped based on the sarcopenia diagnostic criteria. All study participants underwent the same physical examinations and laboratory tests. The relationship between the onset of sarcopenia and fatty liver in middle-aged and elderly patients diagnosed with T2DM was then investigated using statistical analysis.

RESULTS

Comparing the sarcopenia group to the non-sarcopenia group revealed statistically significant variations in gender, BMI, fatty liver prevalence rate, uric acid (UA), alanine aminotransferase (ALT), blood glucose, blood lipid associated indicators, and limb skeletal muscle content. There were, however, no statistically significant differences in age, disease duration, hypertension, smoking, or alcohol intake. There was a positive correlation between BMI, UA, fasting c-peptide, and Appendicular Skeletal Muscle Index (ASMI). Higher levels of BMI, ASMI, and UA were identified as protective variables against sarcopenia by multifactorial logistic regression analysis.

CONCLUSION

Higher levels of BMI, ASMI, and UA can greatly reduce skeletal muscle atrophy in patients with T2DM. Patients with a fatty liver may be less vulnerable to sarcopenia. There is little evidence, however, that a fatty liver works as a preventive factor against sarcopenia.

The relationship between sarcopenia and metabolic dysfunction-associated fatty liver disease among the young and middle-aged populations

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) has been proposed as a new term for diagnosing fatty liver disease, which is considered to be a multi-systemic disease with multiple extrahepatic manifestations, including sarcopenia. The link between sarcopenia and MAFLD remains uncertain, especially among young and middle-aged adults. Thus, we examined the relationship between MAFLD and sarcopenia in young and middle-aged individuals in this study.

METHODS

A total of 2214 individuals with laboratory tests, dual-energy X-ray absorptiometry and ultrasound transient elastography from NHANES 2017-2018 were selected for this study. MAFLD was diagnosed as fatty liver disease with any one of the situations: overweight/obesity, diabetes mellitus, presence of metabolic dysregulation. Sarcopenia was defined by appendicular lean mass adjusted for body mass index (BMI). Multivariable logistic regression and restricted cubic spline (RCS) model were applied to explore the relationship between MAFLD and sarcopenia, and the mediation analyses were also conducted. Moreover, subgroup analyses stratified by BMI and lifestyles were done.

RESULTS

The prevalence of MAFLD was 47.85%, and nearly 8.05% of participants had sarcopenia. The prevalence of sarcopenia was higher in participants with MAFLD (12.75%; 95% CI 10.18-15.31%) than in the non-MAFLD (3.73%; 95% CI 2.16-5.31%). MAFLD was significantly positively associated with sarcopenia after adjustments [OR = 2.87 (95% CI: 1.62-5.09)]. Moreover, significant positive associations were observed between liver fibrosis and sarcopenia prevalence in MAFLD patients (OR = 2.16; 95% CI 1.13-4.15). The RCS curve revealed that MAFLD was linearly associated with sarcopenia. The relationship between the MAFLD and sarcopenia were mediated by C-reactive protein (mediation proportion: 15.9%) and high-density lipoprotein cholesterol (mediation proportion: 18.9%). Subgroup analyses confirmed the association between MAFLD and sarcopenia differed in different lifestyle groups.

CONCLUSIONS

Both MAFLD prevalence and severity was significantly associated with sarcopenia. Thus, clinicians should advise comorbidity screening and lifestyle changes to young and middle-aged patients.

Characteristics of the gut microbiome and metabolic profile in elderly patients with sarcopenia

Introduction: There is growing evidence of research indicating that the gut microbiota is involved in the development of sarcopenia. Nevertheless, there exists a notable deficiency in comprehension concerning the connection between irregularities in the intestinal microbiome and metabolic processes in older individuals suffering from sarcopenia. Methods: To analyze fecal samples obtained from a cohort of 30 older patients diagnosed with sarcopenia as well as 30 older patients without sarcopenia, this study employed 16S rDNA sequencing and liquid chromatography-mass spectrometry (LC-MS)-based non-targeted metabolomics profiling techniques. Results: As a result, we found that 29 genera and 172 metabolites were significantly altered in the sarcopenic patients. Among them, Blautia, Lachnospiraceae_unclassified, and Subdoligranulum were the bacteria with a potential diagnostic value for sarcopenia diagnosis. Correlation analysis between clinical indices and these gut bacteria suggested that the IL-6 level was negatively correlated with Blautia. Function prediction analysis demonstrated that 17 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways differ significantly between sarcopenic and non-sarcopenic patients. The primary classes of metabolites identified in the study included lipids and lipid-like molecules, organic acids and derivatives, and organoheterocyclic compounds. KEGG enrichment analysis showed that purine metabolism, arginine and proline metabolism, alanine, aspartate, and glutamate metabolism, butanoate metabolism, and histidine metabolism may contribute to the development of sarcopenia. The correlation study on gut microbiota and metabolites found that Lachnospiraceae_unclassified was positively associated with seven metabolites that were more abundant in the non-sarcopenia group and negatively correlated with three metabolites that were more abundant in the sarcopenia group. In addition, Subdoligranulum was positively correlated with seven metabolites that were lacking in sarcopenia and negatively correlated with two metabolites that were enriching in sarcopenia. Moreover, Blautia was positively associated with xanthosine. Discussion: We conducted a study on the intestinal microbiota and metabolic profile of elderly individuals with sarcopenia, offering a comprehensive analysis of the overall ecosystem. Through this investigation, we were able to validate existing research on the gut-muscle axis and further investigate potential pathogenic processes and treatment options for sarcopenia.

The association of lipid metabolism and sarcopenia among older patients: a cross-sectional study

Sarcopenia has become a heavy disease burden among the elderly. Lipid metabolism was reported to be involved in many degenerative diseases. This study aims to investigate the association between dysregulated lipid metabolism and sarcopenia in geriatric inpatients. This cross-sectional study included 303 patients aged ≥ 60, of which 151 were diagnosed with sarcopenia. The level of total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), homocysteine (HCY), BMI, and fat percentage, were compared between sarcopenia and non-sarcopenia patients. The Spearman correlation coefficient was used to estimate the association between sarcopenia and the level of lipid metabolism. To determine risk factors related to sarcopenia, a multivariate logistic regression analysis was carried out. Risk prediction models were constructed based on all possible data through principal component analysis (PCA), Logistic Regression (LR), Support Vector Machine (SVM), k-Nearest Neighbor (KNN), and eXtreme Gradient Boosting (XGboost). We observed rising prevalence of sarcopenia with increasing age, decreasing BMI, and fat percentage (p < 0.001, Cochran Armitage test). Multivariate logistic regression analysis revealed sarcopenia's risk factors, including older age, male sex, lower levels of BMI, TC, and TG, and higher levels of LDL and HCY (p < 0.05). The sarcopenia risk prediction model showed the risk prediction value of sarcopenia, with the highest area under the receiver operating curve (AUC) of 0.775. Our study provided thorough insight into the risk factors associated with sarcopenia. It demonstrated that an increase in lipid metabolism-related parameters (BMI, TG, TC), within normal reference ranges, may be protective against sarcopenia. The present study can illuminate the direction and significance of lipid metabolism-related factors in preventing sarcopenia.

Plant-based polyphenol rich protein supplementation attenuated skeletal muscle loss and lowered the LDL level via gut microbiota remodeling in Taiwan's community-dwelling elderly

Sarcopenia, characterized by muscle loss, negatively affects the elderly's physical activity and survival. Enhancing protein and polyphenol intake, possibly through the supplementation of fermented black soybean koji product (BSKP), may alleviate sarcopenia by addressing anabolic deficiencies and gut microbiota dysbiosis because of high contents of polyphenols and protein in BSKP. This study aimed to examine the effects of long-term supplementation with BSKP on mitigating sarcopenia in the elderly and the underlying mechanisms. BSKP was given to 46 participants over 65 years old with early sarcopenia daily for 10 weeks. The participants' physical condition, serum biochemistry, inflammatory cytokines, antioxidant activities, microbiota composition, and metabolites in feces were evaluated both before and after the intervention period. BSKP supplementation significantly increased the appendicular skeletal muscle mass index and decreased the low-density lipoprotein level. BSKP did not significantly alter the levels of inflammatory factors, but significantly increased the activity of antioxidant enzymes. BSKP changed the beta diversity of gut microbiota and enhanced the relative abundance of Ruminococcaceae_UCG_013, Lactobacillus_murinus, Algibacter, Bacillus, Gordonibacter, Porphyromonas, and Prevotella_6. Moreover, BSKP decreased the abundance of Akkermansia and increased the fecal levels of butyric acid. Positive correlations were observed between the relative abundance of BSKP-enriched bacteria and the levels of serum antioxidant enzymes and fecal short chain fatty acids (SCFAs), and Gordonibacter correlated negatively with serum low-density lipoprotein. In summary, BSKP attenuated age-related sarcopenia by inducing antioxidant enzymes and SCFAs via gut microbiota regulation. Therefore, BSKP holds potential as a high-quality nutrient source for Taiwan's elderly, especially in conditions such as sarcopenia.

Sarcopenia in Type 2 Diabetes Mellitus: Study of the Modifiable Risk Factors Involved

(1) Background: Sarcopenia has gained much interest in recent years due to an increase in morbidity. Sarcopenia is associated with type 2 diabetes mellitus (T2DM) and vice versa. There is a paucity of information regarding the prevalence and predictors of sarcopenia among T2DM individuals. The aim of the present study was to determine the prevalence and predictors of sarcopenia among T2DM individuals. (2) Methods: This study included 159 diabetics (cases) and 79 non-diabetics (controls) aged >50 years. The subjects were assessed for demographic and anthropometric parameters. Sarcopenia (according to the Asian Working Group for Sarcopenia 2019 criteria) was assessed using Jammer's hydraulic dynamometer for handgrip strength, dual-energy X-ray absorptiometry for muscle mass, and 6m gait speed. The biochemical investigations included glycated hemoglobin; fasting and prandial glucose; fasting insulin; lipid, renal, liver, and thyroid profiles; serum calcium; phosphorous; vitamin D; and parathyroid hormone (PTH). Appropriate statistical methods were used to determine the significance of each parameter, and a multivariate regression analysis was applied to determine the predictors. (3) Results: The prevalence of sarcopenia was significantly higher among the cases than the controls (22.5% vs. 8.86%, p-0.012). Body mass index (BMI) (OR-0.019, CI-0.001-0.248), physical activity (OR-0.45, CI-0.004-0.475), serum calcium levels (OR-0.155, CI-0.035-0.687), hypertension (OR-8.739, CI-1.913-39.922), and neuropathy (OR-5.57, CI-1.258-24.661) were significantly associated with sarcopenia following multivariate regression analysis. (4) Conclusions: T2DM individuals are prone to sarcopenia, especially those with a low BMI, low physical activity, hypertension, neuropathy, and low serum calcium levels. Hence, by modifying these risk factors among the elderly T2DM, sarcopenia can be prevented.

Genetic Association and Potential Mediators between Sarcopenia and Coronary Heart Disease: A Bidirectional Two-Sample, Two-Step Mendelian Randomization Study

OBJECTIVE

To elucidate the bidirectional correlation of sarcopenia with coronary heart disease (CHD), as well as to investigate the mediating role of cardiometabolic factors and inflammatory biomarkers, a bidirectional two-sample, two-step Mendelian randomization (MR) study was conducted.

METHODS

Summary statistics were obtained from genome-wide association studies (GWAS). In our bidirectional two-sample MR, genetic variants associated with sarcopenia-related traits and CHD were instrumented for the estimation of bidirectional correlations. Besides, genetic variants associated with thirteen cardiometabolic factors and six inflammatory biomarkers were selected for further mediation analyses. To confirm the consistency of the results, several sensitivity analyses were carried out.

RESULTS

Genetically predicted higher appendicular lean mass (OR = 0.835, 95% CI: 0.790-0.882), left hand grip strength (OR = 0.703, 95% CI: 0.569-0.869), right hand grip strength (OR = 0.685, 95% CI: 0.555-0.844), and walking pace (OR = 0.321, 95% CI: 0.191-0.539) reduced CHD risk, while genetic predisposition to CHD did not affect any of the sarcopenia-related traits. Seven mediators were identified for the effects of appendicular lean mass on CHD, including waist-to-hip ratio, hip circumference, systolic blood pressure, low-density lipoprotein cholesterol, total cholesterol, triglycerides, and fasting insulin. The mediation proportion ranged from 10.23% for triglycerides to 35.08% for hip circumference. Hip circumference was found to mediate the relationships between both left (mediation proportion: 24.61%) and right-hand grip strength (24.14%) and CHD, and the link between walking pace and CHD was partially mediated by waist-to-hip ratio (31.15%) and body mass index (26.66%).

CONCLUSION

Our results showed that higher appendicular lean mass, hand grip strength, and walking pace reduced CHD risk, but the causal relationship was not bidirectional. Several mediators were found to mediate the causal pathways between sarcopenia-related traits and CHD, and intervention of these factors may be helpful in terms of CHD prevention in sarcopenia patients.

Dyslipidemia in Muscular Dystrophy: A Systematic Review and Meta-Analysis

BACKGROUND

Muscular dystrophies (MDs) are characterized by chronic muscle wasting but also poorly understood metabolic co-morbidities. We have recently shown that Duchenne MD (DMD) patients, dogs and asymptomatic carriers are affected by a new form of dyslipidemia that may exacerbate muscle damage.

OBJECTIVE

We aimed to perform a systematic review and meta-analysis for evidence that other types of MDs are associated with dyslipidemia compared to healthy controls.

METHODS

Search was conducted using MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials for reports that compare plasma/serum lipids from MD patients and controls, and meta-analysis of cross-sectional studies quantifying total cholesterol, high-density lipoprotein, low density lipoprotein and triglycerides was performed.

RESULTS

Out of 749 studies, 17 met our inclusion criteria for meta-analysis. 14 of the 17 studies (82% ) included investigated myotonic dystrophy (DM); other studies were on pseudohypertrophic MD (PMD) or DMD. As a whole, MD individuals had significantly higher levels of circulating total cholesterol (Hedges' g with 95% confidence interval [CI], 0.80 [0.03 - 1.56]; p = 0.04) and triglycerides (Hedges' g with 95% confidence interval [CI], 2.28[0.63 - 3.92]; p = 0.01) compared to controls. Meta-regression analysis showed the percentage of male gender was significantly associated with the difference in total cholesterol (beta = 0.05; 95% CI, - 0.02 to 0.11; p = 0.043) and high-density lipoprotein (beta = - 9.38; 95% CI, - 16.26 to - 2.50; p = 0.028).

CONCLUSIONS

MD is associated with significantly higher circulating levels of total cholesterol and triglycerides. However, caution on the interpretation of these findings is warranted and future longitudinal research is required to better understand this relationship.

Relationship between lipid profiles and reduced handgrip strength (dynapenia) in hospitalized patients with cirrhosis

BACKGROUND

Dynapenia embraces clinical significance and predictive value separated from skeletal muscle loss among cirrhosis. Moreover, alterations in lipid levels may impact muscle function. It has yet to elucidate the relationship between lipid profiles and muscle strength weakness. We sought to explore which lipid metabolism indicator could be useful to identify patients with dynapenia in daily practice.

METHODS

A retrospective observational cohort study enrolling 262 cirrhotic patients. Analysis of the receiver operating characteristic (ROC) curve was performed to determine the discriminatory cutoff for dynapenia. Multivariate logistic regression was conducted to assess the association between total cholesterol (TC) and dynapenia. Also, we established a model based on the classification and regression tree method.

RESULTS

ROC implicated a cutoff of TC ≤ 3.37 mmol/L to identify dynapenia. Patients with TC ≤ 3.37 mmol/L showed significantly lower handgrip strength (HGS; 20.0 vs. 24.7 kg, P  = 0.003), lower hemoglobin, lower platelet, lower white blood cell count, lower sodium and higher prothrombin-international normalized ratio. A positive correlation was found between TC and HGS values ( r  = 0.1860, P  = 0.003). TC remained a significant association with dynapenia after controlling for variables including age, sex, BMI, and the presence of ascites. The decision tree incorporating TC, BMI, and age had a sensitivity of 71.4%, specificity of 64.9%, and an area under ROC of 0.681.

CONCLUSION

TC ≤ 3.37 mmol/L was significantly associated with the presence of dynapenia. Assessing TC may be helpful for identifying dynapenic patients with cirrhosis in the health care or hospital setting.

Correlation between lipoprotein(a), albuminuria, myostatin and sarcopenia in elderly patients with type 2 diabetes

AIM

To investigate the relationship of the lipoprotein(a), albuminuria, myostatin with sarcopenia in elderly patients with type 2 diabetes (T2D).

METHODS

A total of 461 elderly patients with T2D who were admitted to our hospital were selected as the research subjects. There were 34 cases in line with Asian sarcopenia diagnosis (group A), and 427 patients had no such symptoms as the control group (group C). The levels of lipoprotein(a), albuminuria, myostatin in each group were compared, and the effect factors of muscle loss in elderly patients with T2D were analyzed by univariate/multivariate logistic regression.

RESULTS

The incidence of sarcopenia in 461 elderly patients with T2D in this study was 7.37 % (34/461). However, the levels of appendicular skeletal muscle mass index (ASMI, kg/m²), albumin and epidermal growth factor receptor (eGFR) in group A were lower than those in group C (P < 0.05). The levels of lipoprotein(a), albuminuria, myostatin in group A were higher those in group C (P < 0.05). Additionally, group A had a higher morbidity in diabetic retinopathy and neuropathy. Univariate logistic regression analysis revealed that the risk factors of muscle loss are ASMI, lipoprotein(a), albuminuria, myostatin, diabetic retinopathy and neuropathy. Multivariate Logistic regression analysis showed that the risk factors of muscle loss in elderly patients with T2D were lipoprotein(a), albuminuria, myostatin and diabetic neuropathy.

CONCLUSION

The lipoprotein(a), albuminuria, myostatin and diabetic neuropathy are closely related to the occurrence and development of muscle loss in elderly patients with T2D.

Presence of sarcopenia identifies a special group of lean NAFLD in middle-aged and older people

BACKGROUND

Sarcopenia, the age-related loss of muscle mass and function, is closely associated and frequently concomitant with non-alcoholic fatty liver disease (NAFLD). We aimed to investigate the clinical features of the sarcopenic NAFLD patients from middle-aged and older people.

METHODS

A total of 1305 patients with NAFLD from the Shanghai Changfeng Study were included for analysis. Sarcopenia was diagnosed based on the height-adjusted appendicular skeletal muscle mass (ASM/height²). We comprehensively analyzed the metabolic phenotype, carotid artery condition, liver fibrosis score, and serum metabolomic profile of each participant.

RESULTS

Among the middle-aged and older population, 68.1% of patients with sarcopenia and NAFLD were lean. Sarcopenia was independently associated with increased risk of carotid plaque (OR, 2.22; 95%CI 1.23-4.02) and liver fibrosis (OR, 2.07; 95%CI 1.24-3.44), and the sarcopenic lean NAFLD patients were characterized by a higher risk of carotid plaque (p = 0.008) and liver fibrosis (p = 0.001) than the non-sarcopenic lean NAFLD patients, despite their lower BMI and similar prevalence of metabolic syndrome and diabetes. Further serum metabolomic examination indicated that the sarcopenic lean NAFLD patients presented a distinct metabolomic profile prone to carotid plaque and liver fibrosis, with upregulated serum valine, N-acetylneuraminyl-glycoproteins, lactic acid, small LDL triglycerides and VLDL5 components, and reduced components of HDL4. A sarcopenic characterization score based on above metabolites was established and could also predict increased risk of carotid plaque and liver fibrosis.

CONCLUSION

The presence of sarcopenia identifies a special subgroup of lean NAFLD with increased risk of cardiovascular disease and liver fibrosis clinically.

Characterization of serum protein expression profiles in the early sarcopenia older adults with low grip strength: a cross-sectional study

Background

Sarcopenia refers to the progressive loss of skeletal muscle mass and muscle function, which seriously threatens the quality of life of the older adults. Therefore, early diagnosis is urgently needed. This study aimed to explore the changes of serum protein profiles in sarcopenia patients through a cross-sectional study, and to provide the reference for clinical diagnosis.

Methods

This study was a cross-sectional study carried out in the Tianjin institute of physical education teaching experiment training center from December 2019 to December 2020. Ten older adults were recruited, including 5 sarcopenia and 5 healthy older adults. After a detailed diagnostic evaluation, blood samples were collected to prepare serum for proteomic analysis using the HPLC System Easy nLC method. The differentially expressed proteins (DEPs) were screened by the limma package of R software (version 4.1.0).

Results

A total of 114 DEPs were identified between the patients and healthy older adults, including 48 up-regulated proteins and 66 down-regulated proteins. The functional enrichment analysis showed that the 114 DEPs were significantly enriched in 153 GO terms, which mainly involved in low-density lipoprotein particle remodeling, and negative regulation of immune response,etc. The PPI network further suggested that the cholesteryl ester transfer protein and Apolipoprotein A2 could serve as biomarkers to facilitate diagnosis of sarcopenia.

Conclusions

This study provided a serum proteomic profile of sarcopenia patients, and identified two proteins with diagnostic value, which might help to improve the diagnostic accuracy of sarcopenia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05844-2.

Emerging Evidence of Pathological Roles of Very-Low-Density Lipoprotein (VLDL)

Embraced with apolipoproteins (Apo) B and Apo E, triglyceride-enriched very-low-density lipoprotein (VLDL) is secreted by the liver into circulation, mainly during post-meal hours. Here, we present a brief review of the physiological role of VLDL and a systemic review of the emerging evidence supporting its pathological roles. VLDL promotes atherosclerosis in metabolic syndrome (MetS). VLDL isolated from subjects with MetS exhibits cytotoxicity to atrial myocytes, induces atrial myopathy, and promotes vulnerability to atrial fibrillation. VLDL levels are affected by a number of endocrinological disorders and can be increased by therapeutic supplementation with cortisol, growth hormone, progesterone, and estrogen. VLDL promotes aldosterone secretion, which contributes to hypertension. VLDL induces neuroinflammation, leading to cognitive dysfunction. VLDL levels are also correlated with chronic kidney disease, autoimmune disorders, and some dermatological diseases. The extra-hepatic secretion of VLDL derived from intestinal dysbiosis is suggested to be harmful. Emerging evidence suggests disturbed VLDL metabolism in sleep disorders and in cancer development and progression. In addition to VLDL, the VLDL receptor (VLDLR) may affect both VLDL metabolism and carcinogenesis. Overall, emerging evidence supports the pathological roles of VLDL in multi-organ diseases. To better understand the fundamental mechanisms of how VLDL promotes disease development, elucidation of the quality control of VLDL and of the regulation and signaling of VLDLR should be indispensable. With this, successful VLDL-targeted therapies can be discovered in the future.

Skeletal Muscle in Hypoxia and Inflammation: Insights on the COVID-19 Pandemic

SARS-CoV-2 infection is often associated with severe inflammation, oxidative stress, hypoxia and impaired physical activity. These factors all together contribute to muscle wasting and fatigue. In addition, there is evidence of a direct SARS-CoV-2 viral infiltration into skeletal muscle. Aging is often characterized by sarcopenia or sarcopenic obesity These conditions are risk factors for severe acute COVID-19 and long-COVID-19 syndrome. From these observations we may predict a strong association between COVID-19 and decreased muscle mass and functions. While the relationship between physical inactivity, chronic inflammation, oxidative stress and muscle dysfunction is well-known, the effects on muscle mass of COVID-19-related hypoxemia are inadequately investigated. The aim of this review is to highlight metabolic, immunity-related and redox biomarkers potentially affected by reduced oxygen availability and/or muscle fatigue in order to shed light on the negative impact of COVID-19 on muscle mass and function. Possible countermeasures are also reviewed.