Improvements In Muscle Quality Research Articles

The impact of the addition of Vitamin C, NaCl, clove oil on the muscle of live blunt-snout bream during transportation

The impact of the addition of Vitamin C, NaCl, clove oil on the muscle of live blunt-snout bream during transportation

Selective peroxisome proliferator-activated receptor-α modulator improves hypertriglyceridemia and muscle quality in patients with chronic kidney disease: A retrospective observational study

Patients with chronic kidney disease (CKD) often have additional health problems, including sarcopenia and sarcopenic obesity. These conditions involve ectopic fat accumulation within muscles. This ectopic fat deposition reduces muscle quality, leading to weaker muscle strength and poorer physical performance. Persistent hypertriglyceridemia contributes to ectopic fat accumulation. Metabolic abnormalities, including dyslipidemia, are major factors in CKD development. Triglycerides (TG) and muscle quality are thus important factors in CKD management. Recently developed selective peroxisome proliferator-activated receptor α modulator (SPPARMα) hold promises for improving hypertriglyceridemia. However, their effectiveness and impact on muscle quality in CKD patients remain unclear. This study aimed to evaluate the effect of SPPARMα on muscle quality and its efficacy in CKD patients. This retrospective observational study involved CKD patients with dyslipidemia. We included patients who initiated medications for hypertriglyceridemia. We compared changes in lipid profiles, renal function, and muscle quality, assessed by phase angle, over six months between two groups: those receiving this type of medication and those receiving conventional treatment. Among 245 patients diagnosed with CKD and hypertriglyceridemia, 52 started medications for hypertriglyceridemia. Of these, 26 received SPPARMα, and 26 received conventional lipid-lowering medications (statins, ezetimibe, eicosapentaenoic acid, and fibrates). SPPARMα significantly reduced TG (from 296.8±106.1 to 153.0±86.1, p<0.001) without affecting glomerular filtration rate or urinary protein levels. Conventional treatment also improved TG (from 261.6±89.5 to 173.6±81.3, p<0.001). Only patients treated with SPPARMα showed significant improvement in muscle quality. Their phase angle increased from 5.41±0.6 to 5.55±0.6 after six months of treatment (p<0.05). Our study demonstrates that the newly developed SPPARMα significantly lowers TG levels in CKD patients without harming their kidneys. Additionally, only patients treated with SPPARMα showed improvement in muscle quality. These findings suggest that SPPARMα may be a valuable treatment option for CKD patients with dyslipidemia, particularly those with low muscle quality.

Effects of different culture salinities on the growth and muscle quality of grass carp (Ctenopharyngodon idellus).

Grass carp (Ctenopharyngodon idellus) is an economically important farmed fish. This experiment was conducted to study the effects of different culture salinities on the growth and muscle quality of grass carp. We found that salinity of 0 to 5 had no significant effect on the growth of grass carp, but it significantly decreased at salinities above 5. Compared to salinity 0, the protein content of serum was significantly higher at salinities of 3 and 5. However, all serum biochemical compound measured, except glucose and total protein, decreased significantly at salinity 9. Muscle textural properties of grass carp were significantly higher at salinities of 3 and 5 than at 0, 7, and 9. Salinities of 0 to 3 had no significant effect on muscle nutrition of grass carp, but this parameter tended to decrease at salinities above 7. Salinities of 3 and 5 significantly favored muscle growth and expression of collagen-related genes, whereas the opposite was true for salinities of 7 and 9. These results indicated that grass carp grew normally at salinities of 3 and 5, with some improvement in muscle quality, whereas salinities of 7 and 9 had a negative effect on growth and quality. Therefore, appropriate salinity levels can help to improve the muscle quality of grass carp without affecting their growth.

Molecular Mechanism of ε-Polylysine Treatment of Animal-Derived Foods: Glycine Amidinotransferase Activity Implicates Upregulation of l-Arginine and Creatine.

ε-Polylysine is a novel food preservative approved by the U.S. Food and Drug Administration (FDA), yet the mechanism of its effect on animal-derived foods remains unclear. Assessment of the effect of preservatives on goat meat products is necessary. Herein, metabolite accumulation and protein expression of ε-polylysine (0.025%, w/w) spiked with goat meat were investigated by nontarget metabolomics and proteomics combined with ultrahigh performance liquid chromatography quadrupole-Orbitrap high-resolution-mass spectrometry (UHPLC-Q-Orbitrap HRMS) in a simulated in vitro digestion model. The amino side chain of ε-polylysine increased the activity of glycine aminotransferase due to its nucleophilic nature, inducing a significant upregulation of l-arginine (0.43-0.72 mg kg-1) and creatine (3.98-6.89 mg kg-1), with an improvement in muscle quality of goat meat. Downregulation of enzyme phenylalanine hydroxylase expression led to upregulation of l-phenylalanine (2.26-3.25 mg kg-1) and l-tyrosine (0.98-1.29 mg kg-1). Collectively, this study first revealed the biochemical mechanism of ε-polylysine in goat meat products, which makes available new prospects for more accurate use of ε-polylysine in animal-derived foods.

Changes in Muscle Thickness and Echo Intensity in Chronic Stroke Survivors: A 2-Year Longitudinal Study.

The objective of this study was to identify 2-year longitudinal changes in the muscle thickness (MT) and echo intensity (EI) of the abdominal, thigh, and lower limb muscles in chronic stroke survivors.This study included 15 chronic stroke survivors aged 74.1±9.9 years. The MT, EI, and subcutaneous fat thickness values of the following muscles on the paretic and nonparetic sides were assessed on transverse ultrasound images: rectus abdominis, external oblique, internal oblique, transversus abdominis, rectus femoris (RF), vastus intermedius, vastus lateralis (VL), vastus medialis, tibialis anterior, gastrocnemius, and soleus. The ultrasound measurements were performed both at baseline and 2 years later.After 2 years, the VL on the paretic side showed a significant decrease in MT (p=0.031) and increase in EI (p=0.002), whereas the RF on the nonparetic side showed a significant decrease in EI (p=0.046). Correlation coefficient analyses showed that changes in MT (r=0.668, p=0.012) and EI (r=0.597, p=0.018) of the VL on the paretic side were significantly associated with a change in the body mass index.The findings of this longitudinal study suggest that the VL on the paretic side is subject to deteriorations in muscle quantity and quality, and conversely that the RF on the nonparetic side shows an improvement in muscle quality after 2 years in chronic stroke survivors.

Changes in Muscle Thickness and Echo Intensity in Chronic Stroke Survivors: A 2-Year Longitudinal Study.

Background and PurposeThe objective of this study was to identify 2-year longitudinal changes in the muscle thickness (MT) and echo intensity (EI) of the abdominal, thigh, and lower limb muscles in chronic stroke survivors.MethodsThis study included 15 chronic stroke survivors aged 74.1±9.9 years. The MT, EI, and subcutaneous fat thickness values of the following muscles on the paretic and nonparetic sides were assessed on transverse ultrasound images: rectus abdominis, external oblique, internal oblique, transversus abdominis, rectus femoris (RF), vastus intermedius, vastus lateralis (VL), vastus medialis, tibialis anterior, gastrocnemius, and soleus. The ultrasound measurements were performed both at baseline and 2 years later.ResultsAfter 2 years, the VL on the paretic side showed a significant decrease in MT (p=0.031) and increase in EI (p=0.002), whereas the RF on the nonparetic side showed a significant decrease in EI (p=0.046). Correlation coefficient analyses showed that changes in MT (r=0.668, p=0.012) and EI (r=0.597, p=0.018) of the VL on the paretic side were significantly associated with a change in the body mass index.ConclusionsThe findings of this longitudinal study suggest that the VL on the paretic side is subject to deteriorations in muscle quantity and quality, and conversely that the RF on the nonparetic side shows an improvement in muscle quality after 2 years in chronic stroke survivors.

16-week Combined Exercise Training Improves Muscle Quality In Breast Cancer Survivors

Cancer treatment is associated with skeletal muscle loss, leading to reductions in muscular strength and functional capacity. Exercise training can improve muscular strength in breast cancer survivors (BCS), even without skeletal muscle hypertrophy. Factors such as improved muscle quality (MQ) may contribute to improved function but limited data are available in BCS. PURPOSE: To investigate the effects of exercise training in BCS and healthy controls (HC) on MQ, cross-sectional area (CSA), muscular strength, and physical function and to examine associations between these measures. METHODS: BCS (n = 31, 54 [11] y, 27.5 [5.0] kg/m2) and HC (n = 15, 54 [8] y, 29.3 [4.9] kg/m2) underwent a 16-week combined aerobic and strength training intervention 3x/week for one-hour at a community-based exercise program for BCS. Isokinetic peak torque and maximal voluntary isometric contraction (MVIC) were assessed in the knee extensor muscles. Ultrasound was used to determine muscle CSA and echo intensity of the vastus lateralis. Functional parameters included 6-minute walk (6MWT) and timed up and go (TUG). All measures were taken pre- and post-intervention and were analyzed using a 2x2 repeated measures ANOVA and Pearson’s correlations. Data are mean change [SD]. RESULTS: Echo intensity decreased with training overall (-5.4 [24.6], p = .046), indicating higher MQ, with no change in CSA. A time x group interaction for MVIC showed increased strength after training in BCS (+11.0 [17.2] N·m, p = .001) but not HC (-2.6 [23.7] N·m, p = .673). Physical function improved in both groups (TUG -0.5 [0.9] sec, p < .000; 6 MWT 35.5 [45.0] m, p < .001). At baseline, echo intensity was inversely correlated with MVIC, TUG and 6 MWT in HC only (r = -0.451-0.490, all p < 0.05). No associations in the changes of these variables were observed with training. CONCLUSION: A 16-week exercise intervention improved MQ and functional measures in both BCS and HC, while MVIC increased only in BCS. MQ was moderately correlated with functional and strength measures at baseline in HC but not in BCS. The lack of correlations in BCS suggest that other factors, possibly neural adaptations, may be responsible for the improvements in muscular strength and functional measures seen after an exercise intervention rather than improvements in MQ and CSA.

Integrative analysis of transcriptomics and metabolomics profiling on flesh quality of large yellow croaker Larimichthys crocea fed a diet with hydroxyproline supplementation.

A previous study showed that flesh quality of large yellow croaker (LYC) was improved by feeding dietary hydroxyproline (Hyp, 0·69 %). The aim of the present study was to explore the underlying mechanisms using transcriptomics and metabolomics analysis. The metabolomics analysis showed that muscle metabolite profiles could be clearly separated between the basal diet and Hyp supplementation diet. Metabolites including betaine, Hyp, lactate, glucose-6-phosphate, trimethylamine N-oxide, taurine, creatine, inosine monophosphate, histamine and serine made significant contribution to the separation. Compared with the control diet, the transcriptomics analysis identified a total of 334 different expressed genes, of which 298 genes were up-regulated and thirty-six genes were down-regulated in the Hyp supplementation group. The altered genes of the Hyp supplementation group were involved in collagen metabolism, lipid metabolism and energy metabolism. The integrated results revealed that the increased muscle collagen content in the Hyp supplementation diet was partly because of its enhancement of biosynthesis and the reduction of degradation. The improvement of muscle quality by dietary Hyp supplementation could also be related to a good utilisation of glucose through enhancement of glycolysis. It was concluded that dietary Hyp supplementation could improve flesh quality because of comprehensive metabolism changes including elevated collagen content, glycolysis, lipid metabolism and flesh flavour of LYC. The present study provided a novel strategy to understand the underlying molecular mechanism of flesh quality of LYC fed diet with Hyp supplementation.

High-intensity stretch-shortening contraction training modifies responsivity of skeletal muscle in old male rats

Utilization of high-intensity resistance training to counter age-related sarcopenia is currently debated because of the potential for maladaptation when training design is inappropriate. Training design is problematic because the influence of various loading variables (e.g. contraction mode, repetition number, and training frequency) is still not well characterized at old age. To address this in a precisely controlled manner, we developed a rodent model of high-intensity training consisting of maximally-activated stretch-shortening contractions (SSCs), contractions typical during resistance training. With this model, we determined that at old age, high-repetition SSC training (80 SSCs: 8 sets of 10 repetitions) performed frequently (i.e. 3 days per week) for 4.5 weeks induced strength deficits with no muscle mass gain while decreasing frequency to 2 days per week promoted increases in muscle mass and muscle quality (i.e. performance normalized to muscle mass). This finding confirmed the popular notion that decreasing training frequency has a robust effect with age. Meanwhile, the influence of other loading variables remains contentious. The aim of the present study was to assess muscle adaptation following modulation of contraction mode and repetition number during high-intensity SSC training. Muscles of young (3 month old) and old (30 month old) male rats were exposed to 4.5 weeks of low-repetition static training of 4 (i.e. 4 sets of one repetition) isometric (ISO) contractions 3 days per week or a more moderate-repetition dynamic training of 40 SSCs (i.e. 4 sets of 10 repetitions) 3 days per week. For young rats, performance and muscle mass increased regardless of training protocol. For old rats, no muscle mass adaptation was observed for 4 ISO training while 40 SSC training induced muscle mass gain without improvement in muscle quality, an outcome distinct from modulating training frequency. Muscle mass gain for old rats was accompanied by decreased protein levels of tumor necrosis factor alpha, a mediator of age-related chronic inflammatory signaling, to young levels. These findings suggest that while dynamic high-intensity training with a moderate number of repetitions has a limited capacity for altering muscle quality, such training is a viable strategy for countering age-related inflammatory signaling and modifying muscle mass.

Nonlinear Trimodal Regression Analysis of Radiodensitometric Distributions to Quantify Sarcopenic and Sequelae Muscle Degeneration.

Muscle degeneration has been consistently identified as an independent risk factor for high mortality in both aging populations and individuals suffering from neuromuscular pathology or injury. While there is much extant literature on its quantification and correlation to comorbidities, a quantitative gold standard for analyses in this regard remains undefined. Herein, we hypothesize that rigorously quantifying entire radiodensitometric distributions elicits more muscle quality information than average values reported in extant methods. This study reports the development and utility of a nonlinear trimodal regression analysis method utilized on radiodensitometric distributions of upper leg muscles from CT scans of a healthy young adult, a healthy elderly subject, and a spinal cord injury patient. The method was then employed with a THA cohort to assess pre- and postsurgical differences in their healthy and operative legs. Results from the initial representative models elicited high degrees of correlation to HU distributions, and regression parameters highlighted physiologically evident differences between subjects. Furthermore, results from the THA cohort echoed physiological justification and indicated significant improvements in muscle quality in both legs following surgery. Altogether, these results highlight the utility of novel parameters from entire HU distributions that could provide insight into the optimal quantification of muscle degeneration.

Eicosapentaenoic acid in cancer improves body composition and modulates metabolism

The objective of this review article is to present the most recent intervention studies with EPA on nutritional outcomes in cancer patients, e.g. nutritional status, weight & lean body mass. For this purpose a PubMed(®) and MedLine(®) search of the published literature up to and including January 2014 that contained the keywords: cancer, sarcopenia, EPA, ω-3 fatty acids, weight, intervention trial, muscle mass was conducted. The collected data was summarized and written in text format and in tables that contained: study design, patient' population, sample size, statistical significance and results of the intervention. The paper will cover malignancy, body composition, intervention with EPA, physiological mechanisms of action of EPA, effect of EPA on weight and body composition, future research. In cancer patients deterioration of muscle mass can be present regardless of body weight or Body Mass Index (BMI). Thus, sarcopenia in cancer patients with excessive fat mass (FM), entitled sarcopenic obesity, has gained greater relevance in clinical practice; it can negatively influence patients' functional status, tolerance to treatments & disease prognosis. The search for an effective nutritional intervention that improves body composition (preservation of muscle mass and muscle quality) is of utmost importance for clinicians and patients. The improvement of muscle quality is an even more recent area of interest because it has probable implications in patients' prognosis. Eicosapentaenoic acid (EPA) has been identified as a promising nutrient with the wide clinical benefits. Several mechanisms have been proposed to explain EPA potential benefits on body composition: inhibition of catabolic stimuli by modulating pro-inflammatory cytokines production and enhancing insulin sensitivity that induces protein synthesis; also, EPA may attenuate deterioration of nutritional status resulting from antineoplastic therapies by improving calorie and protein intake as well. Indeed, cancer-related sarcopenia/cachexia is a multifactorial syndrome characterized by inflammation, anorexia, weight loss, and muscle/adipose tissue loss mediated by proinflammatory cytokines, e.g. TNF-α and IL-6, resulting in increased chemotherapy toxicity, costs, morbidity and mortality. With this review we found that EPA can reduce inflammation and has the potential to modulate nutritional status/body composition. In view of the modest survival benefits of chemotherapy/radiotherapy in some cancers, important issues for physicians are to optimize well-being, Quality of Life via nutritional status and adequate body composition. Thus, improvement in nutritional status is a central outcome.

Low- and high-volume strength training induces similar neuromuscular improvements in muscle quality in elderly women

The aim of this study was to compare the effects of low- and high-volume strength training on strength, muscle activation and muscle thickness (MT) of the lower- and upper-body, and on muscle quality (MQ) of the lower-body in older women. Twenty apparently healthy elderly women were randomly assigned into two groups: low-volume (LV, n=11) and high-volume (HV, n=9). The LV group performed one-set of each exercise, while the HV group performed three-sets of each exercise, twice weekly for 13 weeks. MQ was measured by echo intensity obtained by ultrasonography (MQEI), strength per unit of muscle mass (MQST), and strength per unit of muscle mass adjusted with an allometric scale (MQAS). Following training, there was a significant increase (p≤0.001) in knee extension 1-RM (31.8±20.5% for LV and 38.3±7.3% for HV) and in elbow flexion 1-RM (25.1±9.5% for LV and 26.6±8.9% for HV) and in isometric maximal strength of the lower-body (p≤0.05) and upper-body (p≤0.001), with no difference between groups. The maximal electromyographic activation for both groups increased significantly (p≤0.05) in the vastus medialis and biceps brachii, with no difference between groups. All MT measurements of the lower- and upper-body increased similarly in both groups (p≤0.001). Similar improvements were also observed in MQEI (p≤0.01), MQST, and MQAS (p≤0.001) for both groups. These results demonstrate that low- and high-volume strength training promote similar increases in neuromuscular adaptations of the lower- and upper-body, and in MQ of the lower-body in elderly women.

Differential expression of genes characterizing myofibre phenotype

Skeletal muscle is composed of metabolically heterogeneous myofibres that exhibit high plasticity at both the morphological and transcriptional levels. The objective of this study was to employ microarray analysis to elucidate the differential gene expression between the tonic-'red' anterior latissimus dorsi (ALD) muscle, the phasic-'white' posterior latissimus dorsi (PLD) and 'mixed'-phenotype biceps femoris (BF) in 1-week-and 19-week-old male turkeys. A total of 170 differentially expressed genes were identified in the muscle samples analysed (P < 0.05). Gene GO analysis software was utilized to identify top gene networks and metabolic pathways involving differentially expressed genes. Quantitative real-time PCR for selected genes (BAT2D, CLU, EGFR and LEPROT) was utilized to validate the microarray data. The largest differences were observed between ALD and PLD muscles, in which 32 genes were over-expressed and 82 genes were under-expressed in ALD1-PLD1 comparison, and 70 genes were over-expressed and 70 under-expressed in ALD19-PLD19 comparison. The largest number of genes over-expressed in ALD muscles, as compared to other muscles, code for extracellular matrix proteins such as dystroglycan and collagen. The gene analysis revealed that phenotypically 'red' BF muscle has high expression of glycolytic genes usually associated with the 'white' muscle phenotype. Muscle-specific differences were observed in expression levels of genes coding for proteins involved in mRNA processing and translation regulation, proteosomal degradation, apoptosis and insulin resistance. The current findings may have large implications in muscle-type-related disorders and improvement of muscle quality in agricultural species.

Changes in skeletal muscle qualities during enzyme replacement therapy in late‐onset type II glycogenosis: temporal and spatial pattern of mass vs. strength response

Muscle quality is defined as muscle strength generated per unit muscle mass. If enzyme replacement therapy (ERT) has some effects on type II glycogenosis (GSDII) skeletal muscle pathology, we should be able to measure a change in strength and mass. We conducted a prospective study including 11 patients aged 54.2 ± 11.2 years, referring to a single institution and receiving ERT for ≥2 years. Median Walton score was 3 (2.5-6). Lower limb skeletal muscles were assessed by dynamometry and quantitative muscle MRI. Three segments (anterior thigh, posterior thigh, leg) were analysed separately. Clinical-MRI correlations were searched for at T0, T6/T8, and T18/24. Changes in lean and fat body composition were assessed by bioelectrical impedance analysis. We found that the anterior thigh showed the best therapeutic response, with an improvement in muscle quality (muscle mass: +7.5%, p = 0.035; strength: +45%, p = 0.002). BMI and lean body mass increased (p = 0.007). Patients with low BMI showed a better outcome. Intramuscular fat accumulation significantly progressed in spite of ERT (+3.7%, p = 0.001), especially in the poorly responsive posterior thigh muscles. Both clinical assessment and MRI revealed a definite improvement in the anterior thigh muscles. However, progression of intramuscular fat accumulation during ERT, as well as the limited responsiveness of posterior thigh muscles, suggests the necessity for early treatment intervention. The better outcome of patients with low BMI, if confirmed, may indicate that dietary protocols could be adopted as adjuvant measures to ERT in adult GSDII.

Lower extremity power training in elderly subjects with mobility limitations: a randomized controlled trial

This study investigated whether high-velocity high-power training (POW) improved lower extremity muscle power and quality in functionally-limited elders greater than traditional slow-velocity progressive resistance training (STR). Fifty-seven community-dwelling older adults aged 74.2+/-7 (range 65-94 yrs), Short Physical Performance Battery score 7.7+/-1.4, were randomized to either POW (n=23) (12 females), STR (n=22) (13 females) or a control group of lower extremity stretching (CON) (n=12) (6 females). Training was performed three times per week for 12 weeks and subjects completed three sets of double leg press and knee extension exercises at 70% of the one repetition maximum (1RM). Outcome measures included 1RM strength and peak power (PP). Total leg lean mass was determined using dual-energy X-ray absorptiometry to estimate specific strength and specific PP. During training, power output was consistently higher in POW compared to STR for knee extension (approximately 2.3-fold) and leg press (approximately 2.8-fold) exercises (p<0.01). Despite this, PP and specific PP of the knee extensors increased similarly from baseline in POW and STR compared to CON (p<0.01), and no significant time-group interaction occurred for PP of the leg extensors. However, gains in leg press specific PP were significantly greater in POW compared to both STR and CON (p<0.05). Total leg lean mass did not change within any group. A short-term intervention of high-velocity power training and traditional slow-velocity progressive resistance training yielded similar increases of lower extremity power in the mobility-impaired elderly. Neuromuscular adaptations to power training, rather than skeletal muscle hypertrophy, may have facilitated the improvements in muscle quality. Additional studies are warranted to test the efficacy of power training in older individuals with compromised physical functioning.