Search Results (679)

Numerous studies have demonstrated the positive effects of formulated feeds on gonadal and hepatopancreatic development of Eriocheir sinensis. However, there are limited studies on the effects of formulated feeds on the immune homeostasis and metabolism of muscle tissue in E. sinensis during the fattening period. Therefore, this study used metabolomic and lipidomic to systematically analyze the effects of formulated diets on muscle metabolism in female E. sinensis. The results indicate that the formulated feeds improved immune performance by inhibiting inflammatory responses, apoptosis and autophagy. In addition, the feed promoted amino acid metabolism and protein synthesis while decreasing muscle fatty acid metabolism. Metabolomic analysis reveal that pyrimidine metabolism is involved in the regulation of muscle physiological health in fattening female crabs. Lipidomic analysis revealed that the formulated feeds play a role in muscle immune homeostasis, amino acid and fatty acid metabolism by regulating the level of ceramide (Cer (d18:1/22:0)) in sphingolipid metabolism. Through subnetwork analysis, the functional interactions of sphingolipid metabolism with the pathways of sphingolipid signaling, apoptosis regulation, inflammatory response and lipid dynamic homeostasis were identified, which further defined the important role of sphingolipid metabolism in the regulation of muscle physiological health and metabolic homeostasis was further identified. In summary, the formulated feeds effectively promote immune homeostasis and metabolism in the muscle of female E. sinensis during the fattening period. These findings provide a solid theoretical foundation for feed formulation optimization and application in fattening practices. Full article

Pancreatic cancer is frequently accompanied by cancer-associated cachexia, a debilitating metabolic syndrome marked by progressive skeletal muscle wasting and systemic metabolic dysfunction. This study presents a systems biology framework to simultaneously identify therapeutic targets for both pancreatic ductal adenocarcinoma (PDAC) and its associated cachexia (PDAC-CX), using cell-specific genome-scale metabolic models (GSMMs). The human metabolic network Recon3D was extended to include protein synthesis, degradation, and recycling pathways for key inflammatory and structural proteins. These enhancements enabled the reconstruction of cell-specific GSMMs for PDAC and PDAC-CX, and their respective healthy counterparts, based on transcriptomic datasets. Medium-independent metabolic biomarkers were identified through Parsimonious Metabolite Flow Variability Analysis and differential expression analysis across five nutritional conditions. A fuzzy multi-objective optimization framework was employed within the anticancer target discovery platform to evaluate cell viability and metabolic deviation as dual criteria for assessing therapeutic efficacy and potential side effects. While single-enzyme targets were found to be context-specific and medium-dependent, eight combinatorial targets demonstrated robust, medium-independent effects in both PDAC and PDAC-CX cells. These include the knockout of SLC29A2, SGMS1, CRLS1, and the RNF20–RNF40 complex, alongside upregulation of CERK and PIKFYVE. The proposed integrative strategy offers novel therapeutic avenues that address both tumor progression and cancer-associated cachexia, with improved specificity and reduced off-target effects, thereby contributing to translational oncology. Full article

Dietary protein is an essential macronutrient derived from both plant and animal sources required for muscle building, immune function, and wound healing. However, in the United States, protein consumption worsens as individuals age, with 30% of men and 50% of women over 71 consuming inadequate dietary protein due to a variety of factors, including changes in gut function, loss of appetite, tooth loss, financial concerns, and social isolation. The aim of this review is to underscore the need for increased protein requirements in aging populations, highlight potential barriers, synthesize these protein requirements, and also recommend strategies to meet these increased protein needs. Achieving adequate protein status, especially when facing chronic or acute health concerns, is essential to promote muscle and bone strength (because aging is associated with significant decreases in postprandial muscle protein synthesis), to support immune health (due to immunosenescence), and to maintain a good quality of life. For older adults, the literature suggests that a dietary protein intake of at least 1.0–1.2 g/kg/day is required in healthy, aging populations, and intakes of 1.2–1.5 g/kg/day are necessary for those with chronic or acute conditions. These protein intake recommendations can increase to 2.0 g/kg/day in more severe cases of illness, malnutrition, and chronic conditions. The reviewed literature also suggests that evenly balanced protein distributions of 25–30 g of dietary protein (0.4 g/kg) per meal from animal and plant protein sources alike are sufficient to maximize muscle protein synthesis (MPS) rates in older populations. Additionally, pre-sleep protein feeds of 40 g/night may be another strategy to improve daily MPS and amino acid utilization. Full article

Resistance exercise can enhance or preserve muscle mass and/or strength. Modifying factors are secreted following resistance exercise. Biomarkers like cytokines and extracellular vesicles, especially small extracellular vesicles, are released into the circulation and play an important role in cell-to-cell and inter-tissue communications. There is increasing evidence that physical activity itself promotes the release of extracellular vesicles into the bloodstream, suggesting the importance of vesicles in mediating systemic adaptations following exercise. Extracellular vesicles contain proteins, nucleic acids like miRNAs, and other molecules targeting different cell types and tissues of distant organs. Therefore, extracellular vesicles and encapsulated miRNAs are fine tuners of protein synthesis and are important in the adaptation after resistance training. However, there is a lack of strong data supporting the precise mechanisms of these processes. In this literature review, we collected publications related to miRNA and extracellular vesicle profile changes induced by resistance exercise. To the best of our knowledge, the changes in human extracellular vesicle and microRNA profiles following resistance exercise have not been reviewed yet. We aimed to assess the shortcomings and difficulties characterizing this research area, to summarize the existing results to date, and to propose possible solutions that could help standardize the implementation of future investigations. Full article

Parathyroid hormone (PTH) has been studied to determine its broader role in musculoskeletal health, particularly its effects on skeletal muscle. Bone and muscle are inextricably linked via mechanical loading and biochemical signaling, with both processes playing important roles in muscular metabolism and function. Furthermore, the nervous system must maintain muscle mass and function, as neuromuscular transmission controls muscle contraction, protein synthesis, and energy metabolism. As a systemic endocrine regulator, PTH influences the physiology of skeletal muscle—both directly and through interactions with bone and the nervous system, modulating myokines, osteokines, and neuromuscular activity. The intricate relationships between PTH, muscle, bone, and nerves continue to be investigated due to their implications for aging, metabolic pathologies, and musculoskeletal disorders. Full article

Background: Heart failure (HF) is frequently associated with skeletal muscle wasting, reduced functional capacity, and malnutrition. High-protein diets offer a promising nutritional intervention to improve these outcomes in individuals with HF. Objective: This systematic review evaluated randomized controlled trials of high-protein dietary interventions in HF populations, with emphasis on intervention characteristics, quantitative benefits, and risk of bias. Methods: We conducted a comprehensive search in PubMed, MEDLINE, Embase, and Cochrane CENTRAL from inception to June 2025. Eligible studies enrolled adults (≥18 years) with HF, implemented high-protein regimens (≥1.1 g/kg/day or ~25–30% of energy), and reported on functional capacity, body composition, muscle strength, clinical outcomes, or biochemical markers. Two reviewers independently screened, extracted data, and assessed bias (Cochrane RoB 2). Heterogeneity in dosing, duration, and outcomes precluded meta-analysis; we therefore provide a narrative synthesis. Results: Ten trials (nine randomized controlled trials, one pilot) involving 1080 patients (median n = 38; range 21–652) were included. High-protein interventions yielded mean improvements in six-minute walk distance of +32 ± 14 m, lean body mass gain of +1.6 ± 0.9 kg, and 9 ± 4% enhancement in quality-of-life scores; muscle strength effects varied from −2% to +11%. Two studies reported an 18% reduction in HF readmissions (p < 0.05). The risk-of-bias assessment identified two low-risk, three moderate-risk, and one high-risk study. Key limitations include small sample sizes, varied protein dosing (1.1–1.5 g/kg/day), short follow-up (2–6 months), and outcome heterogeneity. Conclusions: High-protein dietary strategies appear to confer modest, clinically relevant gains in functional capacity, nutritional status, and HF readmission risk. Larger, well-powered trials with standardized dosing and longer follow-up are necessary to establish optimal protein targets, long-term efficacy, and safety. Full article

Background/Objectives: Osteosarcopenia, the coexistence of osteoporosis and sarcopenia, in older adults, is an emerging geriatric syndrome linked to functional decline, increased frailty, and higher mortality. Evidence supports the benefits of interventions such as physical exercise and dietary supplementation with vitamin D, calcium, and protein in this population. Additionally, emerging supplements—such as creatine, β-hydroxy-β-methylbutyrate (HMB), probiotics, and prebiotics—are being investigated for their potential to enhance bone density, muscle mass, and physical function. This review aims to examine the current evidence on these novel nutritional strategies and provide a comprehensive synthesis of how these factors may synergistically influence both muscle and bone health. Methods: A comprehensive literature search was conducted across the PubMed/MEDLINE, Embase, Scopus, and Google Scholar databases. Relevant observational studies, clinical trials, systematic reviews, and meta-analyses published from January 2020 to June 2025 were included, and then a reverse search in the bibliography was used to expand on definitions and concepts. Conclusions: Nutritional interventions for osteosarcopenia play a pivotal role in not only improving bone and muscle composition but also enhancing functional outcomes in older adults. Emerging strategies involving creatine monohydrate, HMB, probiotics, and prebiotics show potential as part of a comprehensive patient-centered approach. However, further research is needed to determine the most effective strategies and to identify which patients are most likely to benefit from each supplement. Full article

Background: Sarcopenia is a syndrome associated with aging, characterized by a progressive decline in skeletal muscle mass and function. Its onset compromises the health and longevity of older adults by increasing susceptibility to falls, fractures, and various comorbid conditions, thereby diminishing quality of life and capacity for independent living. Accumulating evidence indicates that moderate-intensity aerobic exercise is an effective strategy for promoting overall health in older adults and exerts a beneficial effect that mitigates age-related sarcopenia. However, the underlying molecular mechanisms through which exercise confers these protective effects remain incompletely understood. Methods: In this study, we established a naturally aging mouse model to investigate the effects of a 16-week treadmill-based aerobic exercise regimen on skeletal muscle physiology. Results: Results showed that aerobic exercise mitigated age-related declines in muscle mass and function, enhanced markers associated with protein synthesis, reduced oxidative stress, and modulated the expression of genes and proteins implicated in mitochondrial quality control. Notably, a single session of aerobic exercise acutely elevated circulating levels of β-hydroxybutyrate (β-HB) and upregulated the expression of BDH1, HCAR2, and PPARG in the skeletal muscle, suggesting a possible role of β-HB–related signaling in exercise-induced muscle adaptations. However, although these findings support the beneficial effects of aerobic exercise on skeletal muscle aging, further investigation is warranted to elucidate the causal relationships and to characterize the chronic signaling mechanisms involved. Conclusions: This study offers preliminary insights into how aerobic exercise may modulate mitochondrial quality control and β-HB–associated signaling pathways during aging. Full article

As life expectancy increases, muscle atrophy, characterized by a decline in muscle mass and strength that can impair mobility, has become a growing concern, highlighting the potential of protein supplementation as a promising intervention strategy. A horse meat hydrolysate, with a molecular weight of less than 3 kDa, derived from m. biceps femoris and produced using the food-grade enzyme Alcalase^® (A4 < 3kDa) was evaluated for its efficacy in mitigating dexamethasone-induced muscle atrophy, a widely accepted model for studying catabolic muscle loss. Administered orally to C57BL/6 mice at dosages of 200 mg/kg or 500 mg/kg body weight for 35 days, A4 < 3kDa effectively countered the weight loss induced by dexamethasone in the whole body, quadriceps, tibialis anterior, and gastrocnemius muscles. Moreover, it increased muscle fiber cross-sectional area and grip strength. These effects were attributed to increased protein synthesis via the protein kinase B (AKT)/forkhead box O3 (FoxO3a)/mammalian target of rapamycin (mTOR) signaling pathway. A4 < 3kDa augmented the phosphorylation of key components of the signaling pathways associated with muscle atrophy, resulting in reduced mRNA expression of Atrogin-1 and MuRF-1. These findings demonstrate the potential of A4 < 3kDa as a functional food ingredient for preventing muscle atrophy. Full article

Background/Objectives: Sarcopenia is an age-related disease resulting in muscle mass deterioration and declining strength and functional ability. Muscle protein degradation pathways are activated through the ubiquitin–proteasome system, which is integral to the pathogenesis of sarcopenia. This study examined the capability of Lactobacillus plantarum beLP1 as a postbiotic ingredient of kimchi that prevents sarcopenia. Methods: We evaluated cell viability and measured diameters in a C2C12 myotube damage model and muscle volume, muscle weight, muscle strength, and the expression of muscle degradation proteins MuRF1 and Atrogin-1 in dexamethasone-induced sarcopenic model rats using a heat-killed beLP1 strain. Results: beLP1 had no cytotoxic effects on C2C12 and prevented dexamethasone-induced cellular damage, suggesting its role in muscle protein degradation pathways. beLP1 treatment significantly prevented the dexamethasone-induced reduction in myotube diameter. In a dexamethasone-induced sarcopenic rat model, oral beLP1 significantly mitigated muscle mass decline and prevented grip strength reduction. Microcomputed tomography demonstrated that beLP1 reduced dexamethasone-induced muscle volume loss. beLP1 treatment reduced Atrogin-1 and Muscle RING-finger protein-1 (MuRF1) and the transcription factor Forkhead box O3 alpha (FoxO3α), which triggers muscle protein breakdown. beLP1 exerts protective effects by inhibiting the ubiquitin-proteasome system and regulating FoxO3α signaling. It increased AKT (Ser473) phosphorylation, which affected muscle protein synthesis, degradation, and cell survival, suggesting its potential to prevent sarcopenia. Conclusions: Heat-killed Lactobacillus plantarum beLP1 alleviates muscle mass wasting and weakness in a dexamethasone-induced sarcopenia model by regulating muscle protein degradation pathways and signaling molecules. Thus, postbiotics may be functional ingredients in sarcopenia prevention. Full article

Glucagon-like peptide-1 (GLP-1) has emerged as a pivotal regulator in the management of glucose homeostasis, glycogen metabolism, and energy balance, positioning it as a critical therapeutic target for addressing obesity, metabolic syndrome, and type 2 diabetes mellitus (T2DM). GLP-1 receptor agonists (GLP-1RAs) have shown promise for improving glycemic control and reducing weight through appetite regulation, delayed gastric emptying, and energy expenditure modulation. This narrative review explores the mechanisms of GLP-1-mediated glycogen metabolism and energy expenditure, particularly in key tissues—pancreas, liver, skeletal muscle, and adipose tissue. In the pancreas, GLP-1 enhances insulin secretion and beta-cell function. In the liver, it promotes glycogen synthesis via insulin-dependent and potential insulin-independent pathways, involving protein kinase B (AKT) and AMP-activated protein kinase (AMPK) signaling. Skeletal muscle benefits from GLP-1 through increased glucose uptake, AMPK activation, and mitochondrial function, facilitating glycogen storage. In adipose tissue, GLP-1 stimulates brown adipose tissue (BAT) thermogenesis and energy expenditure, contributing to weight loss. This increase in energy expenditure, along with enhanced glycogen metabolism, is a plausible mechanism for the weight loss observed with GLP-1RAs. Despite these advances, significant knowledge gaps remain, particularly regarding the direct hepatic effects of GLP-1, the extent to which it modulates glycogen metabolism in vivo, and its impact on thermogenesis in humans. Future research focusing on both the tissue-specific actions of GLP-1 and its systemic role in energy homeostasis and metabolic regulation will be essential for optimizing its therapeutic potential. Full article

Peptides are currently vital components in nutrition with physiological advantages beyond a basic diet. This systematic review aims to explain their significance in metabolic, behavioral, and musculoskeletal health, focusing on their therapeutic benefits, molecular mechanisms, and bioactivities. This systematic review analyzed clinical trials from PubMed and Scopus databases in the time range of 2019 to 2024, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards, that investigated the role of peptides in human nutrition. Eight randomized clinical trials (RCTs) met the predefined metabolic, behavioral, and musculoskeletal health inclusion criteria. Peptides are derived from various sources, including milk, fish, and plants, and show various bioactive characteristics such as anti-inflammatory effect, improved muscle protein synthesis, and immune modulation. Some important findings emphasize their potential to govern metabolic processes, defend against chronic diseases, and enhance gut health. For instance, glucagon-like peptide (GLP-1) controls taste perception and appetite stimulation, and collagen peptides strengthen the musculoskeletal system. Peptides display intriguing potential as nutrients for addressing global health challenges, including behavioral responses, aging, and metabolic syndrome. Future investigations would focus on bioavailability, optimizing dosage, and demographic-specific treatments. Full article

Glycine has the greatest rate of deposition in whole-body proteins among all amino acids in neonates, but its provision from sow’s milk meets only 20% of the requirement of suckling piglets. The results of our recent studies indicate that piglets with intrauterine growth restriction (IUGR) have a reduced ability to synthesize glycine. The present study determined the role of glycine in the growth of sow-reared IUGR piglets. In Experiment 1, 56 newborn piglets (postnatal day 0) with a low birth weight (<1.10 kg) were selected from 14 litters, providing 4 IUGR piglets/litter that were allotted randomly into one of four treatment groups (14 piglets/group). Piglets received oral administration of either 0, 0.1, 0.2 or 0.4 g glycine/kg body weight (BW) twice daily (i.e., 0, 0.2, 0.4 or 0.8 g glycine/kg BW/day) between 0 and 14 days of age. L-Alanine was used as the isonitrogenous control. The BWs of all piglets were recorded each week during the experiment. Two weeks after the initiation of glycine supplementation, blood and tissue samples were collected for biochemical analyses. In Experiment 2, rates of muscle protein synthesis in tissues were determined on day 14 using the ³H-phenylalanine flooding dose technique. Compared with piglets in the control group, oral administration of 0.2, 0.4 and 0.8 g glycine/kg BW/day did not affect their milk intake (p > 0.05) but increased (p < 0.05) concentrations of glycine in plasma by 1.52-, 1.94-, and 2.34-fold, respectively, and body weight by 20%, 37%, and 34%, respectively. The dose of 0.4 g glycine/kg BW/day was the most cost-effective. Consistent with its growth-promoting effect, glycine supplementation stimulated (p < 0.05) the phosphorylation of mechanistic target of rapamycin (MTOR), eukaryotic initiation factor 4E binding protein 1 (4E-BP1), and ribosomal protein S6 kinase beta-1 (p70^S6K) as well as protein synthesis in skeletal muscle, compared with the control group. Collectively, oral administration of glycine activated the MTOR signaling pathway in skeletal muscle and enhanced the growth performance of IUGR piglets. These results indicate that endogenous synthesis of glycine is inadequate to meet the needs of IUGR piglets during the suckling period and that oral supplementation with glycine to these compromized neonates can improve their growth performance. Full article

Background: With growing interest in healthy lifestyles, protein bars have gained popularity. However, many commercial bars contain excessive calories, sugar, and artificial additives that undermine their health benefits. This study aimed to develop a protein bar using natural ingredients with a balanced macronutrient profile. Method: The protein bar formulation used soy protein extract, a plant-based protein source, known for its complete amino acid profile but limited in methionine, which was complemented by oats to nutritionally balance this deficiency. A database was created to evaluate the cost-effectiveness of commercially available protein bars based on consumer feedback. The experimental bar was tested for nutritional value, shelf life, and physiological impact, using only natural ingredients for texture, flavor, and stability. Results: The experimental protein bar had higher protein and fiber content than a selected commercial bar but a shorter shelf life (7 days vs. 90 days) due to the absence of preservatives. The database helped identify target consumer groups and ensure the product was affordable and nutritionally effective. Conclusion: This study demonstrates that using natural, complementary ingredients can create a protein bar with a more balanced nutrient profile while avoiding harmful additives. The final product supports muscle protein synthesis through its high-quality protein content and promotes glycemic control and satiety via its fiber-rich, low-sugar formulation and metabolic processes, offering a healthier alternative to commercial options, with a focus on consumer health and cost-effectiveness. Full article

Chondrocytes maintain cartilage integrity through coordinated regulation of extracellular matrix (ECM) synthesis and remodeling. These processes depend on ECM dynamic interactions, mediated by integrin-based focal adhesions and associated cytoskeletal components. While the roles of core adhesion proteins are well described, the involvement of sarcoglycans (SGs) remains unclear in chondrocytes. Drawing parallels from striated muscle, where the SG subcomplex stabilizes the sarcolemma, we hypothesized that SGs similarly integrate into chondrocyte adhesion complexes. This study investigated the SGs (α, β, γ, δ) expression with cytoskeletal and adhesion proteins, including actin and vinculin, in human chondrocytes cultured by immunofluorescence, qPCR, and siRNA-mediated silencing. All four SG isoforms were expressed in the cytoplasmic and membrane domains, with enrichment at focal adhesion sites. Double labeling revealed SG colocalization with F-actin stress fibers and vinculin, indicating integration into the core adhesion complex. Silencing of each SG resulted in disrupted actin stress fibers, diffuse vinculin distribution, reduced focal plaque number, and a change in cell morphology. These findings support the hypothesis that SGs regulate actin cytoskeletal dynamics and focal contact stabilization. Loss of SG function compromises chondrocyte shape and adhesion, highlighting the importance of these glycoproteins also in non-muscle cells. Full article