Muscle-related Parameters Research Articles

Comprehensive diagnostic value of VBQ scores and paravertebral muscle quality parameters in osteoporotic vertebral fractures

ObjectiveBoth vertebral bone quality (VBQ) scores and paravertebral muscle quality can predict osteoporotic vertebral fractures (OVF). This study aimed to compare the diagnostic value of opportunistic VBQ scores and sarcopenia for OVF and to determine if their combined use could enhance diagnostic efficacy. MethodsA total of 194 patients, matched 1:1 by age and sex, were included. VBQ scores and paravertebral muscle cross-sectional areas (CSA) were measured from lumbar MRI. Independent risk factors for OVF were determined using multivariate conditional logistic regression. The predictive value of VBQ and muscle-related parameters for OVF was assessed with receiver operating characteristic curves. ResultsVBQ, CSA, and degree of fat infiltration (DFF) showed significant differences between the fracture and non-fracture groups (p < 0.001). Multivariate analysis identified lower multifidus (MF) CSA, higher MF DFF, and higher VBQ as independent risk factors for OVF. Thresholds of 3.46 for VBQ and 11.83 cm2 for MF CSA yielded AUC values of 0.668 and 0.736, respectively, for predicting OVF. Combining VBQ and MF CSA notably enhanced the sensitivity and specificity of OVF diagnosis. ConclusionsThe predictive value of MF CSA in anticipating OVF was marginally superior to that of VBQ and MF DFF. Furthermore, the concurrent utilization of VBQ and MF CSA substantially enhanced the diagnostic accuracy of OVF. Considering that both VBQ and MF CSA can be opportunistically obtained during routine examinations, individuals with a VBQ ≥3.46 and MF CSA ≤11.83 cm2 should be categorized as high risk for OVF, warranting timely preventive measures.

Association Between Two Muscle-Related Parameters and Postoperative Complications in Patients Undergoing Colorectal Tumor Resection Surgery.

This study aimed to investigate the associations of 2 preoperative muscle-related parameters, the third lumbar vertebra skeletal muscle index (L3 SMI) for muscle mass and the Hounsfield unit average calculation (HUAC) for muscle density, with the occurrence of postoperative complications among patients undergoing colorectal tumor resection surgery under general anesthesia. We hypothesized that muscle-related parameters are associated with the occurrence of postoperative complications. This was a single-center, retrospective observational study. Adult patients who underwent colorectal tumor resection surgery under general anesthesia between 2018.09.01 and 2021.09.01 were enrolled. The last abdominal computed tomography (CT) scan images obtained within 3 months before surgery were used to calculate the L3 SMI and HUAC. The primary outcome was defined as the occurrence of any postoperative complications corresponding to Clavien-Dindo classification before discharge. The secondary outcome was defined as the occurrence of any severe postoperative complications (Clavien-Dindo grade ≥3) before discharge. Multivariable logistic regression analyses were used to estimate the association between muscle-related parameters and incidence of postoperative complications. Patients' baseline demographics, past medical history and intraoperative parameters were adjusted in the multivariable logistic regression analysis. A total of 317 patients with a median age of 66 (58-72) years were included. Sarcopenia (muscle mass reduction) patients in our cohort and myosteatosis (muscle density decline) were present in 254 (80.1 %) and 79 (24.9%) patients, respectively. A total of 135 patients (42.6 %) developed postoperative complications. According to the multivariable logistic regression, myosteatosis (odds ratio [OR], 1.8, 95% confidence interval [CI], 1.0-3.3, P = .039) was significantly associated with postoperative complications. A significant association was observed between myosteatosis and postoperative complications (corresponding to Clavien-Dindo classification before discharge), especially severe postoperative complications (Clavien-Dindo grade ≥3) in patients undergoing colorectal tumor resection. Screening for myosteatosis with HUAC using the CT before surgery may help clinicians identify high-risk perioperative patients early.

Associations between muscle quality and whole-body vibration exercise-induced changes in plasma hypoxanthine following an oral glucose load in healthy male subjects.

Blood levels of hypoxanthine (HX) have been suggested as potential biomarkers associated with intramuscular metabolic dynamics in response to exercise. This pilot randomized crossover trial (UMIN000036520) aimed to investigate the changes in plasma HX after whole-body vibration exercise (WBVE) and their relationships with body composition and muscle-related parameters, enrolling eighteen healthy male volunteers. In the WBVE-alone intervention, the study subjects performed 20-min of WBVE. In the OGTT → WBVE intervention, a 75-g oral glucose load (OGL) was administered 30 min prior to the start of the WBVE intervention. Blood samples were collected before the start and 10 min after the end of WBVE in both interventions. WBVE resulted in a significant increase in plasma HX levels, which was accompanied by increased blood ammonia, pyruvic acid, and lactic acid levels. The HX increase following WBVE was suppressed by prior OGL. In the WBVE-alone intervention, there were no significant correlations between the post-WBVE changes in plasma HX (ΔHX) levels and any of the clinical parameters. On the other hand, in the OGTT → WBVE intervention, ΔHX showed significant negative correlations with muscle mass (ρ = -0.62, p = 0.01), strength (ρ = -0.71, p = 0.005), and muscle quality (ρ = -0.81, p = 0.0007) in the legs. In conclusion, these findings suggest possible associations between post-WBVE increases in plasma HX levels and muscle status, particularly under the glucose-supplemented condition. The measurement of plasma HX concentrations following WBVE may have clinical applications in the identification of high-risk populations for sarcopenia.

MRI‑based vertebral bone quality score is a comprehensive index reflecting the quality of bone and paravertebral muscle

BACKGROUNDRecently, vertebral bone quality (VBQ) score has been shown to predict bone mineral density (BMD) and spine-related postoperative complications. However, in clinical work, we found that patients with higher VBQ scores also had more severe paravertebral muscle degeneration. PURPOSETo explore the ability of the VBQ score to evaluate BMD and paravertebral muscle quality. STUDY DESIGN/SETTINGRetrospective single-center cohort. PATIENT SAMPLEPatients in the spinal surgery department of our hospital. OUTCOME MEASURESBone mineral density and T-score were measured by dual-energy X-ray absorptiometry (DXA). The Picture Archiving and Communication Systems (PACS) measured the cross-sectional area (CSA) of the paravertebral muscles. Image J software was used to measure the degree of fat infiltration (DFF) of the paraspinal muscle. METHODSPatients who underwent lumbar MRI and DXA simultaneously within two weeks were enrolled. The VBQ score was calculated using T1-weighted lumbar MRI images. Firstly, BMD-related and muscle-related parameters of patients with different VBQ scores were compared. Then, the correlation coefficients between the VBQ score and the parameters of BMD and paravertebral muscle were calculated. Finally, multivariate linear analysis was used to compare the contribution of each variable to the VBQ score. RESULTSA total of 101 patients were eventually included in this study for analysis. When the VBQ score was greater than 3.0, the patients were mostly female, older, less likely to smoke, and had lower BMD. Interestingly, we found that patients with VBQ scores greater than 3.0 had smaller CSA of the paravertebral muscles (ES: 17.53±3.36 vs 19.13±3.97, p=.032; total: 29.59±5.27 vs 34.12±7.02, p<.001) and higher DFF (MF: 22.47±5.93 vs 19.64±5.28, p=.015; ES: 17.71±4.67 vs 15.74±4.62, p=.038; PM: 13.70±3.32 vs 11.33±3.02, p<.001; average: 17.96±3.78 vs 15.57±3.42, p=.001). The VBQ score was negatively correlated with the CSA (MF: r=−0.316, p=.001; ES: r =−0.388, p=.001; PM: r=0.388, p=.001) and positively correlated with the DFF (MF: r=0.344, p<.001; ES: r=0.439, p<.001; PM: =0.416, p<.001). In multivariate linear analysis, BMD, total CSA, and average DFF determined the value of the VBQ score, and the contribution of paravertebral muscle was higher than that of BMD (BMD: r=−0.203, p=.024; total CSA: r=−0.294, p=.003; average DFF: r=0.261, p=.011). CONCLUSIONSThis study is the first to find a positive association between the VBQ score and paravertebral muscle degeneration, and this association may be independent of BMD. VBQ can reflect the quality of bone and paravertebral muscle, which is its special advantage in clinical application.

Association of Gene Variants with Seasonal Variation in Muscle Strength and Aerobic Capacity in Elite Skiers.

Background: The training of elite skiers follows a systematic seasonal periodization with a preparation period, when anaerobic muscle strength, aerobic capacity, and cardio-metabolic recovery are specifically conditioned to provide extra capacity for developing ski-specific physical fitness in the subsequent competition period. We hypothesized that periodization-induced alterations in muscle and metabolic performance demonstrate important variability, which in part is explained by gene-associated factors in association with sex and age. Methods: A total of 34 elite skiers (20.4 ± 3.1 years, 19 women, 15 men) underwent exhaustive cardiopulmonary exercise and isokinetic strength testing before and after the preparation and subsequent competition periods of the World Cup skiing seasons 2015-2018. Biometric data were recorded, and frequent polymorphisms in five fitness genes, ACE-I/D (rs1799752), TNC (rs2104772), ACTN3 (rs1815739), and PTK2 (rs7460, rs7843014), were determined with specific PCR reactions on collected DNA. Relative percentage changes of cardio-pulmonary and skeletal muscle metabolism and performance over the two seasonal periods were calculated for 160 data points and subjected to analysis of variance (ANOVA) to identify hypothesized and novel associations between performance alterations and the five respective genotypes and determine the influence of age × sex. A threshold of 0.1 for the effect size (h2) was deemed appropriate to identify relevant associations and motivate a post hoc test to localize effects. Results: The preparation and competition periods produced antidromic functional changes, the extent of which varied with increasing importance for anaerobic strength, aerobic performance, cardio-metabolic efficiency, and cardio-metabolic/muscle recovery. Only peak RER (-14%), but not anaerobic strength and peak aerobic performance, and parameters characterizing cardio-metabolic efficiency, differed between the first and last studied skiing seasons because improvements over the preparation period were mostly lost over the competition period. A number of functional parameters demonstrated associations of variability in periodic changes with a given genotype, and this was considerably influenced by athlete "age", but not "sex". This concerned age-dependent associations between periodic changes in muscle-related parameters, such as anaerobic strength for low and high angular velocities of extension and flexion and blood lactate concentration, with rs1799752 and rs2104772, whose gene products relate to sarcopenia. By contrast, the variance in period-dependent changes in body mass and peak VO2 with rs1799752 and rs2104772, respectively, was independent of age. Likely, the variance in periodic changes in the reliance of aerobic performance on lactate, oxygen uptake, and heart rate was associated with rs1815739 independent of age. These associations manifested at the post hoc level in genotype-associated differences in critical performance parameters. ACTN3 T-allele carriers demonstrated, compared to non-carriers, largely different periodic changes in the muscle-associated parameters of aerobic metabolism during exhaustive exercise, including blood lactate and respiration exchange ratio. The homozygous T-allele carriers of rs2104772 demonstrated the largest changes in extension strength at low angular velocity during the preparation period. Conclusions: Physiological characteristics of performance in skiing athletes undergo training period-dependent seasonal alterations the extent of which is largest for muscle metabolism-related parameters. Genotype associations for the variability in changes of aerobic metabolism-associated power output during exhaustive exercise and anaerobic peak power over the preparation and competition period motivate personalized training regimes. This may help to predict and maximize the benefit of physical conditioning of elite skiers based on chronological characteristics and the polymorphisms of the ACTN3, ACE, and TNC genes investigated here.

Patterns of Muscle-Related Risk Factors for Sarcopenia in Older Mexican Women.

Early detriment in the muscle mass quantity, quality, and functionality, determined by calf circumference (CC), phase angle (PA), gait time (GT), and grip strength (GSt), may be considered a risk factor for sarcopenia. Patterns derived from these parameters could timely identify an early stage of this disease. Thus, the present work aims to identify those patterns of muscle-related parameters and their association with sarcopenia in a cohort of older Mexican women with neural network analysis. Methods: Information from the functional decline patterns at the end of life, related factors, and associated costs study was used. A self-organizing map was used to analyze the information. A SOM is an unsupervised machine learning technique that projects input variables on a low-dimensional hexagonal grid that can be effectively utilized to visualize and explore properties of the data allowing to cluster individuals with similar age, GT, GSt, CC, and PA. An unadjusted logistic regression model assessed the probability of having sarcopenia given a particular cluster. Results: 250 women were evaluated. Mean age was 68.54 ± 5.99, sarcopenia was present in 31 (12.4%). Clusters 1 and 2 had similar GT, GSt, and CC values. Moreover, in cluster 1, women were older with higher PA values (p < 0.001). From cluster 3 upward, there is a trend of worse scores for every variable. Moreover, 100% of the participants in cluster 6 have sarcopenia (p < 0.001). Women in clusters 4 and 5 were 19.29 and 90 respectively, times more likely to develop sarcopenia than those from cluster 2 (p < 0.01). Conclusions: The joint use of age, GSt, GT, CC, and PA is strongly associated with the probability women have of presenting sarcopenia.

Exploring how plasma- and muscle-related parameters affect trout hemolysis as a route to prevent hemoglobin-mediated lipid oxidation of fish muscle

Hemoglobin (Hb) is a powerful promoter of lipid oxidation, particularly in muscle of small pelagic fish species and fish by-products, both having high Hb-levels and highly unsaturated lipids. As Hb is located within the red blood cells (RBCs) it is here hypothesized that the perishable polyunsaturated fatty acids (PUFAs) can be protected from oxidation by limiting hemolysis during early fish processing. Using a model system consisting of washed-resuspended trout (Oncorhynchus mykiss) RBCs (wr-RBCs), the aim of this study was to evaluate how RBC lysis under cold storage was affected by selected parameters linked to blood or muscle: bacterial growth, energy status, pH, RBC membrane lipid oxidation and colloidal osmotic pressure (COP). The results indicated that bacterial growth had a modest effect on hemolysis while pH-values typical for post mortem fish muscle (6.4–6.8), and absence of glucose or albumin stimulated hemolysis. The rapid hemolysis observed at pH 6.4–6.8 correlated with lipid oxidation of the RBC membrane, while the lower hemolysis at pH 7.2–8.0 occurred with low, or without any RBC membrane lipid oxidation. When hemin was added to the RBCs at pH 6.8 hemolysis was induced without parallel RBC membrane oxidation, pointing at Hb-autoxidation and hemin-release per se as important events triggering lysis in fish muscle. Altogether, the study provided valuable findings which ultimately can aid development of new tools to combat lipid oxidation in post mortem fish muscle by limiting hemolysis.

HR-pQCT for the Evaluation of Muscle Quality and Intramuscular Fat Infiltration in Ageing Skeletal Muscle.

Myosteatosis is the infiltration of fat in skeletal muscle during the onset of sarcopenia. The quantification of intramuscular adipose tissue (IMAT) can be a feasible imaging modality for the clinical assessment of myosteatosis, important for the early identification of sarcopenia patients and timely intervention decisions. There is currently no standardized method or consensus for such an application. The aim of this study was to develop a method for the detection and analysis of IMAT in clinical HR-pQCT images of the distal tibia to evaluate skeletal muscle during the ageing process, validated with animal and clinical experimentation. A pre-clinical model of ovariectomized (OVX) rats with known intramuscular fat infiltration was used, where gastrocnemii were scanned by micro-computed tomography (micro-CT) at an 8.4 μm isotropic voxel size, and the images were analyzed using our modified IMAT analysis protocol. IMAT, muscle density (MD), and muscle volume (MV) were compared with SHAM controls validated with Oil-red-O (ORO) staining. Furthermore, the segmentation and IMAT evaluation method was applied to 30 human subjects at ages from 18 to 81 (mean = 47.3 ± 19.2). Muscle-related parameters were analyzed with functional outcomes. In the animal model, the micro-CT adipose tissue-related parameter of IMAT% segmented at −600 HU to 100 HU was shown to strongly associate with the ORO-positively stained area (r = 0.898, p = 0.002). For the human subjects, at an adjusted threshold of −600 to −20 HU, moderate positive correlations were found between MV and MD (r = 0.642, p < 0.001), and between MV and IMAT volume (r = 0.618, p < 0.01). Moderate negative correlations were detected between MD and IMAT% (r = −0.640, p < 0.001). Strong and moderate associations were found between age and MD (r = −0.763, p < 0.01), and age and IMAT (r = 0.559, p < 0.01). There was also a strong correlation between IMAT% and chair rise time (r = 0.671, p < 0.01). The proposed HR-pQCT evaluation protocol for intramuscular adipose-tissue produced MD and IMAT results that were associated with age and physical performance measures, and were of good predictive value for the progression of myosteatosis or sarcopenia. The protocol was also validated on animal skeletal muscle samples that showed a good representation of histological lipid content with positive correlations, further supporting the clinical application for the rapid evaluation of muscle quality and objective quantification of skeletal muscle at the peripheral for sarcopenia assessment.

Specific lysophosphatidylcholine and acylcarnitine related to sarcopenia and its components in older men

BackgroundMetabolic profiling may provide insights into the pathogenesis and identification of sarcopenia; however, data on the metabolic basis of sarcopenia and muscle-related parameters among older adults remain incompletely understood. This study aimed to identify the associations of metabolites with sarcopenia and its components, and to explore metabolic perturbations in older men, who have a higher prevalence of sarcopenia than women.MethodsWe simultaneously measured the concentrations of amino acids, carnitine, acylcarnitines, and lysophosphatidylcholines (LPCs) in serum samples from a cross-sectional study of 246 Chinese older men, using targeted metabolomics. Sarcopenia and its components, including skeletal muscle index (SMI), 6-m gait speed, and handgrip strength were assessed according to the algorithm of the Asian Working Group for Sarcopenia criteria. Associations were determined by univariate and multivariate analyses.ResultsSixty-five (26.4%) older men with sarcopenia and 181 (73.6%) without sarcopenia were included in the study. The level of isovalerylcarnitine (C5) was associated with the presence of sarcopenia and SMI. Regarding the overlapped metabolites for muscle parameters, among ten metabolites associated with muscle mass, six metabolites including leucine, octanoyl-L-carnitine (C8), decanoyl-L-carnitine (C10), dodecanoyl-L-carnitine (C12) and tetradecanoyl-L-carnitine (C14), and LPC18:2 were associated with handgrip strength, and three of which (C12, C14, and LPC18:2) were also associated with gait speed. Specifically, tryptophan was positively associated and glycine was negatively associated with handgrip strength, while glutamate was positively correlated with gait speed. Isoleucine, branched chain amino acids, and LPC16:0 were positively associated with SMI. Moreover, the levels of LPC 16:0,18:2 and 18:0 contributed significantly to the model discriminating between older men with and without sarcopenia, whereas there were no significant associations for other amino acids, acylcarnitines, and LPC lipids.ConclusionsThese results showed that specific and overlapped metabolites are associated with sarcopenic parameters in older men. This study highlights the potential roles of acylcarnitines and LPCs in sarcopenia and its components, which may provide valuable information regarding the pathogenesis and management of sarcopenia.

Effect on an Oral Nutritional Supplement with β-Hydroxy-β-methylbutyrate and Vitamin D on Morphofunctional Aspects, Body Composition, and Phase Angle in Malnourished Patients.

This is a retrospective study of data from clinical practice to observe the effect of a high-calorie, high-protein oral nutritional supplement (ONS) with β-hydroxy-β-methylbutyrate (HMB) on nutritional status, body weight, and muscle-related parameters in 283 adult patients with or at risk of malnutrition under standard of care, 63% being cancer patients. They were recommended to increase physical activity and energy and protein intake from regular diet plus two servings per day of a specialized ONS enriched with HMB or standard ONS for up to 6 months. Dietary records, adherence and tolerance to ONS, nutritional status, body composition, handgrip strength, and blood analysis at the beginning and the end of the intervention were recorded. This program improved nutritional status from 100% malnourished or at risk of malnutrition at baseline to 80% well-nourished at final visit. It also increased body weight by 3.6–3.8 kg, fat-free mass by 0.9 to 1.3 kg, and handgrip strength by 4.7 to 6.2 kg. In a subgroup of patients (n = 43), phase angle (PhA), and body cell mass (BCM) increased only in the patients receiving the ONS enriched with HMB (0.95 (0.13) vs. −0.36 (0.4), and 2.98 (0.5) vs. −0.6 (1.5) kg, mean difference (SE) from baseline for PhA and BCM, respectively), suggesting the potential efficacy of this supplement on muscle health.

Phase angle from bioelectrical impedance analysis is a useful indicator of muscle quality.

BackgroundMethods that facilitate muscle quality measurement may improve the diagnosis of sarcopenia. Current research has focused on the phase angle (PhA) obtained through bioelectrical impedance analysis (BIA) as an indicator of cellular health, particularly cell membrane integrity and cell function. The current study therefore aimed to evaluate the relationship between the PhA and muscle quality and muscle‐related parameters and to determine factors associated with the PhA. Moreover, we attempted to determine the cut‐off value of PhA for predicting sarcopenia.MethodsFirst‐year university students (830 male students, 18.5 ± 0.6 years old; 422 female students, 18.3 ± 0.5 years old) and community‐dwelling elderly individuals (70 male individuals, 74.4 ± 5.5 years old; 97 female individuals, 73.1 ± 6.4 years old) were included. PhA and other body composition data were measured using BIA, while muscle quality was calculated by dividing handgrip strength by upper limbs muscle mass. The relationship between PhA and the aforementioned parameters were then analysed, after which the cut‐off value of PhA for predicting sarcopenia was examined.ResultsMultiple linear regression analysis revealed that age, skeletal muscle mass index (SMI), and muscle quality were independently associated with PhA in both sexes [male (age: standardized regression coefficient (β) = −0.43, P < 0.001, SMI: β = 0.61, P < 0.001, muscle quality: β = 0.13, P < 0.001) and female (age: β = −0.56, P < 0.001, SMI: β = 0.52, P < 0.001, muscle quality: β = 0.09, P = 0.007)]. Participants with sarcopenia had a significantly lower PhA compared with those without it (sarcopenia vs. non‐sarcopenia: young male participants, 5.51 ± 0.41° vs. 6.25 ± 0.50°, P < 0.001; young female participants, 4.88 ± 0.16° vs. 5.37 ± 0.44°, P = 0.005; elderly female participants: 4.14 ± 0.29° vs. 4.63 ± 0.42°, P = 0.009). Although no significant findings were observed in elderly male participants, the same tendency was noted. Receiver operating characteristic (ROC) curve analysis indicated that PhA had good predictive ability for sarcopenia in young male, elderly male, young female, and elderly female participants (area under the ROC curve of 0.882, 0.838, 0.865, and 0.850, with cut‐off PhA values of 5.95°, 5.04°, 5.02°, and 4.20° for predicting sarcopenia, respectively).ConclusionsThe PhA reflected muscle quality and exhibited good accuracy in detecting sarcopenia, suggesting its utility as an index for easily measuring muscle quality, which could improve the diagnosis of sarcopenia.

Computed tomography-based multiple body composition parameters predict outcomes in Crohn\u2019s disease

BackgroundThe efficacy of computed tomography-based multiple body composition parameters in assessing disease behavior and prognosis has not been comprehensively evaluated in Crohn’s disease. This study aimed to assess the association of body composition parameters with disease behavior and outcomes in Crohn’s disease and to compare the efficacies of indexes derived from body and lumbar spinal heights in body composition analysis.ResultsOne hundred twenty-two patients with confirmed Crohn’s disease diagnoses and abdominal computed tomography scans were retrospectively included in this study. Skeletal muscle, visceral, and subcutaneous fat indexes were calculated by dividing each type of tissue area by height2 and lumbar spinal height2. Parameters reflecting the distribution of adiposity were also assessed. Principal component analysis was used to deal with parameters with multicollinearity. Patients were grouped according to their disease behavior (inflammatory vs. structuring/penetrating) and outcomes. Adverse outcome included need for intestinal surgery or anti-TNF therapy. Predictors of disease course from multiple parameters were evaluated using multivariate analysis. Indexes derived from body and lumbar spinal heights were strongly correlated (r, 0.934–0.995; p < 0.001). Low skeletal muscle-related parameters were significantly associated with complicated disease behavior in multivariate analysis (p = 0.048). Complicated disease behavior (p < 0.001) and adipose tissue parameters-related first principal component (p = 0.029) were independent biomarkers for predicting adverse outcomes.ConclusionsSkeletal muscle and adipose tissue principle component were associated with complicated Crohn’s disease behavior and adverse outcome, respectively. Indexes derived from body and lumbar spinal heights have similar efficacies in body composition analysis.

(-)-Epicatechin-Enriched Extract from Camellia sinensis Improves Regulation of Muscle Mass and Function: Results from a Randomized Controlled Trial.

Loss of skeletal muscle mass and function with age represents an important source of frailty and functional decline in the elderly. Antioxidants from botanical extracts have been shown to enhance the development, mass, and strength of skeletal muscle by influencing age-related cellular and molecular processes. Tannase-treated green tea extract contains high levels of the antioxidants (−)-epicatechin (EC) and gallic acid that may have therapeutic benefits for age-related muscle decline. The aim of this study was to investigate the effect of tannase-treated green tea extract on various muscle-related parameters, without concomitant exercise, in a single-center, randomized, double-blind, placebo-controlled study. Administration of tannase-treated green tea extract (600 mg/day) for 12 weeks significantly increased isokinetic flexor muscle and handgrip strength in the treatment group compared with those in the placebo (control) group. In addition, the control group showed a significant decrease in arm muscle mass after 12 weeks, whereas no significant change was observed in the treatment group. Blood serum levels of follistatin, myostatin, high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, IL-8, insulin-like growth factor-1 (IGF-1), and cortisol were analyzed, and the decrease in myostatin resulting from the administration of tannase-treated green tea extract was found to be related to the change in muscle mass and strength. In summary, oral administration of tannase-treated green tea extract containing antioxidants without concomitant exercise can improve muscle mass and strength and may have therapeutic benefits in age-related muscle function decline.

Effects of Resistance Training With or Without Protein Supplementation on Body Composition and Resting Energy Expenditure in Patients 2-7Years PostRoux-en-Y Gastric Bypass: a Controlled Clinical Trial.

Resistance training (RT) and adequate protein intake are recommended as strategies to preserve fat-free mass (FFM) and resting metabolic demand after bariatric surgery. However, the effect of both interventions combined in the late postoperative period is unclear. This study investigated the effects of RT, isolated and combined with protein supplementation, on body composition and resting energy expenditure (REE) in the late postoperative period of Roux-en-Y gastric bypass (RYGB). This controlled trial involved patients who were 2-7years postRYGB. Participants were partially matched on body mass index (BMI), age, sex, and years after surgery, and divided into four groups, placebo maltodextrin (control [CON]; n = 17), whey protein supplementation (PRO; n = 18), RT combined with placebo (RTP; n = 13), and RT combined with whey protein supplementation (RTP + PRO; n = 15)-considering the participants who completed the protocol. REE was measured by indirect calorimetry and body composition by multifrequency electrical bioimpedance. Participant characteristics (40.3 ± 8.3years old; average BMI 29.7 ± 5.3kg/m2; 88.9% females) were similar among groups. The RTP+PRO group showed an increase of 1.46 ± 1.02kg in FFM and 0.91 ± 0.64kg in skeletal muscle mass (SMM), which was greater than the equivalent values in the CON group (- 0.24 ± 1.64kg, p = 0.006 and - 0.08 ± 0.96kg, p = 0.008, respectively). There was no significant time-by-group interaction for absolute or relative REE. Combined RT and adequate protein intake via supplementation can increase FFM and SMM in the late postoperative period without changing REE. These associated strategies were effective in improving muscle-related parameters and potentially in improving the patients' physical function.

Muscle-Related Parameters as Determinants of Survival in Patients with Stage I-III Gastric Cancer Undergoing Gastrectomy.

Purpose: This study aimed to evaluate the prognostic potential of muscle-related parameters (MRPs) at the level of the third lumbar vertebra (L3) using computerized tomography (CT) images in patients with stage I-III gastric cancer (GC) who underwent curative gastric resection.Methods: Patients with stage I-III GC who underwent curative gastric resection between October 2006 and June 2014 were enrolled in this study. In addition to demographic and clinical parameters, MRPs, such as skeletal muscle index (SMI), skeletal muscle radiation attenuation (SMRA), paraspinal muscle index (PMI), and paraspinal muscle radiation attenuation (PMRA), at the L3 level using CT images were collected and analyzed. The Kaplan-Meier method was used to estimate survival, and a Cox proportional hazard model was used to calculate the hazard ratio. In addition, the Pearson correlation coefficient was obtained as a measure of the linear relationship between the variables.Results: Data from 339 patients (233 men and 116 women) were analyzed. A strong correlation between SMI and PMI (r = 0.91); and SMRA and PMRA (r = 0.80) were observed, but only weak correlations between SMI and SMRA; and PMI and PMRA were found. When using the Cox model, SMRA or PMRA was a determinant of survival, but SMI and PMI were not. In the full model formed by adding SMRA or PMRA to a baseline model that included demographic and clinical variables, the C-index increased above 0.8, indicating excellent discrimination for both overall survival (OS) and disease-free survival (DFS). Moreover, the C-index of the model containing PMRA was higher than that of the model containing SMRA. Finally, there was a weak correlation between the prognostic nutritional index and SMRA or PMRA.Conclusions: With the multivariate Cox model, SMRA and PMRA appeared to determine survival. In addition, adding SMRA or PMRA to the baseline model increased the C-index above 0.8, indicating excellent discrimination for both OS and DFS. Moreover, compared to SMRA, the model containing PMRA appears to be a more accurate model for survival determination.

Mechanical Properties of Muscles around the Shoulder in Breast Cancer Patients: Intra‐rater and Inter‐rater Reliability of the MyotonPRO

Patients with breast cancer typically experience changes in the properties of muscles around the shoulder. However, there is no appropriate evaluation tool for these changes. The primary objective was to investigate the inter-rater and intra-rater reliability of muscle-related parameters measured by the MyotonPRO, a myotonometer device. The secondary objective was to investigate differences in properties of muscle around the shoulder between the mastectomy side and the other side. Cross-sectional reliability study. Outpatient clinic in a tertiary care university-affiliated hospital. Twenty-two patients with breast cancer who underwent mastectomy. Muscle tone, stiffness, and elasticity of the pectoralis major (PM), sternocleidomastoid (SCM), and upper trapezius (UT) were measured using the MyotonPRO. Rater 1 performed two sets of measurements with a time interval of 30 minutes to determine intra-rater reliability. Rater 2 performed measurements during the interval between the two sets of rater 1. Reliability was assessed using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. A paired t-test was used to compare muscle properties between the affected and unaffected sides. Frequency (tone, Hz), stiffness (N/m), and decrement (elasticity). Intra-rater reliability was excellent (ICC > 0.75, 0.85-0.98) for all parameters of the PM, SCM, and UT in the affected and unaffected upper limbs of patients with breast cancer. Inter-rater reliability was fair to excellent for all parameters except unaffected PM elasticity (ICC = 0.34). There were significant differences in all parameters of the PM between the affected and unaffected sides. There were no significant differences in the parameters of the SCM and UT between the two sides. Our findings indicate that the MyotonPRO device is a feasible tool to quantify PM, UT, and SCM muscle properties (stiffness, tone, and elasticity) in patients with breast cancer. III.

Oxygen Uptake On-Kinetics during Low-Intensity Resistance Exercise: Effect of Exercise Mode and Load.

Oxygen uptake (VO2) kinetics has been analyzed through mathematical modeling of constant work-rate exercise, however, the exponential nature of the VO2 response in resistance exercise is currently unknown. The present work assessed the VO2 on-kinetics during two different sub maximal intensities in the inclined bench press and in the seated leg extension exercise. Twelve males (age: 27.2 ± 4.3 years, height: 177 ± 5 cm, body mass: 79.0 ± 10.6 kg and estimated body fat: 11.4 ± 4.1%) involved in recreational resistance exercise randomly performed 4-min transitions from rest to 12% and 24% of 1 repetition maximum each, of inclined bench press (45°) and leg extension exercises. During all testing, expired gases were collected breath-by-breath with a portable gas analyzer (K4b2, Cosmed, Italy) and VO2 on-kinetics were identified using a multi-exponential mathematical model. Leg extension exercise exhibited a higher R-square, compared with inclined bench press, but no differences were found in-between exercises for the VO2 kinetics parameters. VO2 on-kinetics seems to be more sensitive to muscle related parameters (upper vs. lower body exercise) and less to small load variations in the resistance exercise. The absence of a true slow component indicates that is possible to calculate low-intensity resistance exercise energy cost based solely on VO2 measurements.

Oxandrolone protects against the development of multiorgan failure, modulates the systemic inflammatory response and promotes wound healing during burn injury

Oxandrolone is a synthetic oral non-aromatizable testosterone derivative. This drug has been used successfully for several decades to safely treat growth delays in various diseases including Turner’s syndrome. Currently the use of oxandrolone is under clinical testing in children with burn injury; the available data indicate that the anabolic steroid increases net muscle protein balance, maintains lean body mass, and reduces intensive care unit stay. Although oxandrolone is already in clinical trials in burn patients, preclinical burn-related studies with oxandrolone – especially those that go beyond muscle-related parameters and focus on burn-associated organ dysfunction, inflammatory response and wound healing – remain to be conducted. In the current project, using a well-characterized murine model of third-degree burn, we have tested the effect of oxandrolone on indices of organ injury, clinical chemistry parameters and plasma levels of inflammatory mediators. In oxandrolone-treated mice (1mg/kg/day for up to 21 days) there was a significant amelioration of burn-induced accumulation of myeloperoxidase levels in heart and lung (but not the liver and kidney) and significantly lower degree of malon dialdehyde accumulation in the liver (but not the heart, lung and kidney). Oxandrolone-treated mice showed a significant attenuation of the burn-induced elevation in circulating alkaline aminotransferase and amylase levels, while blood urea nitrogen and creatinine levels remained unaffected, indicative of protective effects of the anabolic hormone against burn-induced hepatic and pancreatic (but not renal) functional impairment. Multiple burn-induced inflammatory mediators (TNF-α, IL-1α, IL-1β, IL-4, IL-6, IL-10, IL-12, IP-10, G-CSF, GM-CSF and interferon-γ) were significantly lower in the plasma of oxandrolone-treated animals after burn injury than in the plasma of controls subjected to burns. Finally, oxandrolone significantly accelerated burn wound healing. We conclude that oxandrolone improves organ function, modulates the systemic inflammatory response and accelerates wound healing in a murine model of burn injury.

Animal-Derived Protein Consumption Is Associated with Muscle Mass and Strength in Community-Dwellers: Results from the Milan EXPO Survey.

Behavioral factors, including protein intake, influence the quantity and quality of skeletal muscle. The aim of this study was to explore the relationship between animal-derived protein intake and muscle mass and function in a large sample of unselected community-dwellers. The VIP (Very Important Protein) study, conducted during Expo 2015 in Milan, was a population survey aimed at assessing major health metrics in a population outside of the research setting, with a special focus on the relation between animal-derived protein intake and muscle mass and function. A brief questionnaire exploring lifestyle habits, dietary preferences and the consumption of selected foods was administered. Muscle mass was estimated by calf circumference (CC) and mid-arm muscle circumference (MAMC) of the dominant side. Muscle strength of upper and lower extremities was assessed through handgrip strength testing and repeated chair stand test, respectively. The mean age of the 1,853 participants was 50.3 years (standard deviation: 15.7; range: 18-98 years), of whom 959 (51.7%) were women. Participants in the highest tertile of protein consumption showed better performance at both the handgrip strength (p <0.001) and chair stand tests than those in the lowest tertile (p <0.01). The same results were found for CC (p <0.001) and MAMC (p <0.001). Participants with high protein intake and engaged in regular physical activity showed the higher scores in all the assessed domains. The results of the VIP survey suggest an association between animal-derived protein intake and muscle mass and strength across ages. Our findings also indicate a synergistic effect of animal-derived protein intake and physical activity on muscle-related parameters.

Instrumented Assessment of Physical Activity Is Associated With Muscle Function but Not With Muscle Mass in a General Population

Self-reported physical activity has shown to affect muscle-related parameters. As self-report is likely biased, this study aimed to assess the association between instrumented assessment of physical activity (I-PA) and muscle-related parameters in a general population. Included were 156 young-to-middle-aged and 80 older community-dwelling adults. Seven days of trunk accelerometry (DynaPort MoveMonitor, McRoberts B.V.) quantified daily physical activity (i.e., active/inactive duration, number and mean duration of active/inactive periods, and number of steps per day). Muscle-related parameters included muscle mass, handgrip strength, and gait speed. I-PA was associated with handgrip strength in young-to-middle-aged adults and with gait speed in older adults. I-PA was not associated with muscle mass in either age group. The association between I-PA and muscle-related parameters was age dependent. The lack of an association between I-PA and muscle mass indicates the relevance of muscle function rather than muscle mass.