BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic...BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients.展开更多
Skeletal muscle alterations(SMA)are increasingly recognized as both contributors and consequences of metabolic dysfunction-associated steatotic liver disease(MASLD),affecting disease progression and outcomes.Sarcopeni...Skeletal muscle alterations(SMA)are increasingly recognized as both contributors and consequences of metabolic dysfunction-associated steatotic liver disease(MASLD),affecting disease progression and outcomes.Sarcopenia is common in patients with MASLD,with a prevalence ranging from 20%to 40%depending on the population and diagnostic criteria used.In advanced stages,such as metabolic dysfunction-associated steatohepatitis and fibrosis,its prevalence is even higher.Sarcopenia exacerbates insulin resistance,systemic inflammation,and oxidative stress,all of which worsen MASLD.It is an independent risk factor for fibrosis progression and poor outcomes including mortality.Myosteatosis refers to the abnormal accumulation of fat within muscle tissue,leading to decreased muscle quality.Myosteatosis is prevalent(>30%)in patients with MASLD,especially those with obesity or type 2 diabetes,although this can vary with the imaging techniques used.It reduces muscle strength and metabolic efficiency,further contributing to insulin resistance and is usually associated with advanced liver disease,cardiovascular complications,and lower levels of physical activity.Altered muscle metabolism,which includes mitochondrial dysfunction and impaired amino acid metabolism,has been reported in metabolic syndromes,including MASLD,although its actual prevalence is unknown.Altered muscle metabolism limits glucose uptake and oxidation,worsening hyperglycemia and lipotoxicity.Reduced muscle perfusion and oxygenation due to endothelial dysfunction and systemic metabolic alterations are common in MASLD associated with comorbidities,such as obesity,hypertension,and atherosclerosis.It decrea-ses the muscle capacity for aerobic metabolism,leading to fatigue and reduced physical activity in patients with MASLD,aggravating metabolic dysfunction.Various SMA in MASLD worsen insulin resistance and hepatic fat accumulation,may accelerate progression to fibrosis and cirrhosis,and increase the risk of cardiovascular disease and mortality.Management strategies for SMA include resistance training,aerobic exercise,and nutritional support(e.g.,high-protein diets,vitamin D,and omega-3 fatty acids),which are essential for mitigating skeletal muscle loss and improving outcomes.However,pharmacological agents that target the muscle and liver(such as glucagon-like peptide-1 receptor agonists)show promise but have not yet been approved for the treatment of MASLD.展开更多
Background N^(6)-methyladenosine(m^(6)A)methylation is a key epigenetic modification that can modulate gene expression and strongly affect mammalian developmental processes.However,the genome-wide methylation of long ...Background N^(6)-methyladenosine(m^(6)A)methylation is a key epigenetic modification that can modulate gene expression and strongly affect mammalian developmental processes.However,the genome-wide methylation of long non-coding RNAs(lncRNAs)and its implications for the development of skeletal muscle remain poorly understood.Bovine skeletal muscle samples from five developmental stages were analyzed in this study to establish lncRNA methylome and transcriptomic maps.Results Globally,59.67%of lncRNAs in skeletal muscle with m^(6)A modifications,and this percentage decreased progressively during development.lncRNA expression levels were positively associated with the number of m^(6)A peaks,with lncRNAs possessing 3 or more peaks showing significantly higher expression levels than those with 1 or 2 peaks.Specific lncRNAs involved in skeletal muscle development were identified through two analytical approaches.The first approach employed weighted gene co-expression network analysis(WGCNA)of transcriptomic data to identify correlations between annotated lncRNAs and growth-related traits,resulting in 21 candidate hub lncRNAs.The intersection of these 21 hub lncRNAs with 151 differentially methylated lncRNAs(DM-lncRNAs)identified 10 shared candidate lncRNAs.The second approach integrated MeRIP-seq and RNA-seq data to identify 36 lncRNAs that were both differentially m^(6)A modified and differentially expressed(dme-lncRNAs).GO and KEGG enrichment analyses of cis-target genes associated with these dme-lncRNAs identified eight candidate lncRNAs.Combining the results from the two approaches identified 16 key m^(6)A-modified lncRNAs likely involved in skeletal muscle development.Conclusions These findings highlight the regulatory and functional significance of dynamic lncRNA methylation in skeletal muscle development.展开更多
Vein graft(VG)failure(VGF)is associated with VG intimal hyperplasia,which is characterized by abnormal accumulation of vascular smooth muscle cells(VSMCs).Most neointimal VSMCs are derived from pre-existing VSMCs via ...Vein graft(VG)failure(VGF)is associated with VG intimal hyperplasia,which is characterized by abnormal accumulation of vascular smooth muscle cells(VSMCs).Most neointimal VSMCs are derived from pre-existing VSMCs via a process of VSMC phenotypic transition,also known as dedifferentiation.There is increasing evidence to suggest that ginger or its bioactive ingredients may block VSMC dedifferentiation,exerting vasoprotective functions;however,the precise mechanisms have not been fully characterized.Therefore,we investigated the effect of ginger on VSMC phenotypic transition in VG remodeling after transplantation.Ginger significantly inhibited neointimal hyperplasia and promoted lumen(L)opening in a 3-month VG,which was primarily achieved by reducing ferroptotic stress.Ferroptotic stress is a pro-ferroptotic state.Contractile VSMCs did not die but instead gained a proliferative capacity and switched to the secretory type,forming neointima(NI)after vein transplantation.Ginger and its two main vasoprotective ingredients(6-gingerol and 6-shogaol)inhibit VSMC dedifferentiation by reducing ferroptotic stress.Network pharmacology analysis revealed that 6-gingerol inhibits ferroptotic stress by targeting P53,while 6-shogaol inhibits ferroptotic stress by targeting 5-lipoxygenase(Alox5),both promoting ferroptosis.Furthermore,both ingredients co-target peroxisome proliferator-activated receptor gamma(PPARγ),decreasing PPARγ-mediated nicotinamide adenine dinucleotide phosphate(NADPH)oxidase 1(Nox1)expression.Nox1 promotes intracellular reactive oxygen species(ROS)production and directly induces VSMC dedifferentiation.In addition,Nox1 is a ferroptosis-promoting gene that encourages ferroptotic stress production,indirectly leading to VSMC dedifferentiation.Ginger,a natural multi-targeted ferroptotic stress inhibitor,finely and effectively prevents VSMC phenotypic transition and protects against venous injury remodeling.展开更多
The muscular system plays a critical role in the human body by governing skeletal movement,cardiovascular function,and the activities of digestive organs.Additionally,muscle tissues serve an endocrine function by secr...The muscular system plays a critical role in the human body by governing skeletal movement,cardiovascular function,and the activities of digestive organs.Additionally,muscle tissues serve an endocrine function by secreting myogenic cytokines,thereby regulating metabolism throughout the entire body.Maintaining muscle function requires iron homeostasis.Recent studies suggest that disruptions in iron metabolism and ferroptosis,a form of iron-dependent cell death,are essential contributors to the progression of a wide range of muscle diseases and disorders,including sarcopenia,cardiomyopathy,and amyotrophic lateral sclerosis.Thus,a comprehensive overview of the mechanisms regulating iron metabolism and ferroptosis in these conditions is crucial for identifying potential therapeutic targets and developing new strategies for disease treatment and/or prevention.This review aims to summarize recent advances in understanding the molecular mechanisms underlying ferroptosis in the context of muscle injury,as well as associated muscle diseases and disorders.Moreover,we discuss potential targets within the ferroptosis pathway and possible strategies for managing muscle disorders.Finally,we shed new light on current limitations and future prospects for therapeutic interventions targeting ferroptosis.展开更多
Enhancing the firefighting protective clothing with exceptional thermal barrier and temperature sensing functions to ensure high fire safety for firefighters has long been anticipated,but it remains a major challenge....Enhancing the firefighting protective clothing with exceptional thermal barrier and temperature sensing functions to ensure high fire safety for firefighters has long been anticipated,but it remains a major challenge.Herein,inspired by the human muscle,an anisotropic fire safety aerogel(ACMCA)with precise self-actuated temperature monitoring performance is developed by combining aramid nanofibers with eicosane/MXene to form an anisotropically oriented conductive network.By combining the two synergies of the negative temperaturedependent thermal conductive eicosane,which induces a high-temperature differential,and directionally ordered MXene that establishes a conductive network along the directional freezing direction.The resultant ACMCA exhibited remarkable thermoelectric properties,with S values reaching 46.78μV K^(−1)andκvalues as low as 0.048 W m^(−1)K^(−1)at room temperature.Moreover,the prepared anisotropic aerogel ACMCA exhibited electrical responsiveness to temperature variations,facilitating its application in intelligent temperature monitoring systems.The designed anisotropic aerogel ACMCA could be incorporated into the firefighting clothing as a thermal barrier layer,demonstrating a wide temperature sensing range(50-400℃)and a rapid response time for early high-temperature alerts(~1.43 s).This work provides novel insights into the design and application of temperature-sensitive anisotropic aramid nanofibers aerogel in firefighting clothing.展开更多
BACKGROUND Skeletal muscle alterations(SMAs)are being increasingly recognized in patients with metabolic dysfunctionassociated steatotic liver disease(MASLD)and appear to be associated with deleterious outcomes in the...BACKGROUND Skeletal muscle alterations(SMAs)are being increasingly recognized in patients with metabolic dysfunctionassociated steatotic liver disease(MASLD)and appear to be associated with deleterious outcomes in these patients.However,their actual prevalence and pathophysiology remain to be elucidated.AIM To determine the prevalence of SMAs and to assess the significance of circulating myokines as biomarkers in patients with MASLD.METHODS Skeletal muscle strength and muscle mass were measured in a cross-sectional study in a cohort of 62 patients fulfilling MASLD criteria,recruited from the outpatient clinics of a tertiary level hospital.The degree of fibrosis and liver steatosis was studied using abdominal ultrasound and transitional elastography.Anthropometric and metabolic characteristics as well as serum levels of different myokines were also determined in the MASLD cohort.Statistical analysis was performed comparing results according to liver fibrosis and steatosis.RESULTS No significant differences were found in both skeletal muscle strength and skeletal muscle mass in patients with MASLD between different stages of liver fibrosis.Interestingly,serum levels of fibroblast growth factor-21(FGF21)were significantly higher in patients with MASLD with advanced hepatic fibrosis(F3-F4)than in those with lower fibrosis stages(F0-F2)(197.49±198.27 pg/mL vs 95.62±83.67 pg/mL;P=0.049).In addition,patients with MASLD with severe hepatosteatosis(S3)exhibited significantly higher serum levels of irisin(1116.87±1161.86 pg/mL)than those with lower grades(S1-S2)(385.21±375.98 pg/mL;P=0.001).CONCLUSION SMAs were uncommon in the patients with MASLD studied.Higher serum levels of irisin and FGF21 were detected in patients with advanced liver steatosis and fibrosis,respectively,with potential implications as biomarkers.展开更多
The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces....The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.展开更多
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor...BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing.展开更多
Background: Aging-induced cardiac hypertrophy and reduced skeletal muscle strength contribute to increased disease risk and life burden in the elderly. FNDC5 acts as a protective muscle factor in both cardiac and skel...Background: Aging-induced cardiac hypertrophy and reduced skeletal muscle strength contribute to increased disease risk and life burden in the elderly. FNDC5 acts as a protective muscle factor in both cardiac and skeletal muscle. This study aims to examine the relationship between cardiac FNDC5 and aging-related cardiac hypertrophy and decreased skeletal muscle strength. Methods: Male young C57BL/6 mice (5 months old, n = 6) and aged mice (21 months old, n = 6) were utilized in the study and housed in a specific pathogen-free (SPF) environment. Prior to the experiment, grip strength tests were performed on the mice, and heart tissues were collected for morphological analysis, including the assessment of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) and fibronectin type III-containing structural domain 5 (FNDC5) protein levels. Furthermore, myosin heavy chain II (MyHC II), skeletal muscle-specific transcription factor (MyoD), muscle RING-finger protein-1 (MuRF1), and FNDC5 levels were evaluated in the quadriceps muscle. The correlations between heart weight and FNDC5 expression levels, as well as skeletal muscle indices in the mice, were subsequently analyzed. Result: Aging leads to cardiac hypertrophy and reduced expression of PGC-1α and FNDC5 proteins. Concurrently, there is a decline in the strength of skeletal muscle, along with decreased expression of MyHC II and increased expression of MURF1 and MyoD. Correlation analysis demonstrated strong positive associations between myocardial FNDC5 protein levels and limb grip strength, as well as MyHC II, and strong negative associations with MyoD and MuRF1. Conclusion: There may be a significant association between aging-induced cardiac hypertrophy and decreased skeletal muscle strength, with FNDC5 potentially playing a crucial role as a regulatory molecule facilitating communication between the heart and skeletal muscle.展开更多
The“longevity protein”SIRT5 could hold the key to delaying age-related muscle decline.A study led by researchers from the Institute of Zoology(IOZ)of the Chinese Academy of Sciences and Capital Medical University in...The“longevity protein”SIRT5 could hold the key to delaying age-related muscle decline.A study led by researchers from the Institute of Zoology(IOZ)of the Chinese Academy of Sciences and Capital Medical University in Beijing reveals that SIRT5 mitigates skeletal muscle aging by blocking pro-inflammatory pathways.Published in Nature Metabolism on March 14,2025,the work identifies SIRT5’s interaction with protein kinase TBK1 as critical to preserving muscle mass and function.展开更多
This study examined the repeated bout effect(RBE)on muscle damage markers following two bouts of neuromuscular electrical stimulation(NMES)in untrained individuals.Following familiarization,participants received 45 co...This study examined the repeated bout effect(RBE)on muscle damage markers following two bouts of neuromuscular electrical stimulation(NMES)in untrained individuals.Following familiarization,participants received 45 consecutive NMES to the biceps brachii at an intensity that produced low evoked force for the elbow flexors.Muscle damage markers(maximal voluntary isometric contraction[MVIC],elbow range of motion[ROM],muscle soreness via visual analogue scale[VAS]scores,pressure pain threshold[PPT],and muscle thickness)were measured before(PRE),after(POST),1 day after(24 POST),and 2 days after(48 POST)NMES.Following 1 week of rest,procedures were replicated.Separate repeated measures two-way ANOVAs examined each measure.There were no interactions or bout main effects for MVIC or ROM.Time main effects indicated PRE MVIC was greater than POST(p=0.002)and 24-POST(p=0.024),and PRE ROM was greater than POST(p=0.036).There was no interaction for muscle thickness.Respective time and bout main effects indicated muscle thickness at PRE was less than POST(p=0.017),and second-bout muscle thickness(p=0.050)was less compared to the initial-bout.For PPT,there was an interaction(p=0.019).Initial-bout PRE PPT was less than POST(p=0.033).Initial-bout 48-POST PPT was less than second-bout 48-POST(p=0.037).There was a significant interaction for VAS(p=0.009).Initial-bout PRE VAS was less than POST(p=0.033)and 24-POST(p=0.015).Initial-bout POST and 24-POST VAS were greater than second-bout POST(p=0.023)and 24-POST(p=0.006),respectively.The results support RBE on muscle damage markers related to inflammation,but not MVIC and ROM.展开更多
Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through mic...Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through microbiome modulation,their therapeutic impact on gut dysfunction-induced bone and muscle loss remains to be elucidated.Employing dextran sulfate sodium(DSS)-induced gut dysfunction model and wide-spectrum antibiotics(ABX)-treated mice model,our study revealed that gut dysfunction instigates muscle and bone loss,accompanied by microbial imbalances.Importantly,Bifidobacterium animalis subsp.lactis A6(B.lactis A6)administration significantly ameliorated muscle and bone loss by modulating gut microbiota composition and enhancing butyrate-producing bacteria.This intervention effectively restored depleted butyrate levels in serum,muscle,and bone tissues caused by gut dysfunction.Furthermore,butyrate supplementation mitigated musculoskeletal loss by repairing the damaged intestinal barrier and enriching beneficial butyrate-producing bacteria.Importantly,butyrate inhibited the NF-κB pathway activation,and reduced the secretion of corresponding inflammatory factors in T cells.Our study highlights the critical role of dysbiosis in gut dysfunction-induced musculoskeletal loss and underscores the therapeutic potential of B.lactis A6.These discoveries offer new microbiome directions for translational and clinical research,providing promising strategies for preventing and managing musculoskeletal diseases.展开更多
Sarcomerogenesis,the addition of serial sarcomeres in skeletal muscle myofibrils and fibres,is a natural occurrence during growth and maturation of animals,including humans.However,the detailed mechanisms that allow f...Sarcomerogenesis,the addition of serial sarcomeres in skeletal muscle myofibrils and fibres,is a natural occurrence during growth and maturation of animals,including humans.However,the detailed mechanisms that allow for sarcomerogenesis are not fully understood.In some diseases,such as cerebral palsy in children,sarcomerogenesis appears to be inhibited or at least reduced,1,2 often causing severe restrictions in muscle and joint function.展开更多
Objective:To evaluate the efficacy and safety of transcutaneous electrical acupoint stimulation(TEAS)for muscle atrophy in patients with immobilization after surgical fixation of foot and ankle fractures.Methods:This ...Objective:To evaluate the efficacy and safety of transcutaneous electrical acupoint stimulation(TEAS)for muscle atrophy in patients with immobilization after surgical fixation of foot and ankle fractures.Methods:This was a two-arm randomized controlled trial wherein 80 patients were recruited and divided into control(n=40)and intervention(n=40)groups.The control group received conventional orthopedic treatment,whereas the intervention group received TEAS and conventional treatment.The intervention group received TEAS 3 times a week for 30 min each time for 8 weeks.The primary out-comes were muscle thickness(MT)and cross-sectional area(CSA)of the rectus femoris and gastroc-nemius muscles,whereas the secondary outcome measure was echo intensity(EI).Data were collected before the fixation operations(baseline assessment)and 4 and 8 weeks after intervention.Results:Compared with baseline,the MT and CSA were reduced in both groups by the end of treatment,whereas EI increased in both groups.At week 4,the reduction in the rectus femoris CSA in the inter-vention group was significantly lower than that in the control group(P=0.02);however,the between-group differences in the MT and EI(all P>0.05)were not significant.No serious adverse events were observed in either group.Conclusion:Our study showed that TEAS can improve muscle atrophy by attenuating the decline in the muscle CSA.Because this was only a pilot trial,subsequent studies will need longer follow-ups and larger sample sizes.展开更多
Background:While muscle contractility increases with muscle temperature,there is no consensus on the best warm-up protocol to use before resistance training or sports exercise due to the range of possible warm-up and ...Background:While muscle contractility increases with muscle temperature,there is no consensus on the best warm-up protocol to use before resistance training or sports exercise due to the range of possible warm-up and testing combinations available.Therefore,the objective of the current study was to determine the effects of different warm-up types(active,exercise-based vs.passive)on muscle function tested using different activation methods(voluntary vs.evoked)and performance test criteria(maximum force vs.rate-dependent contractile properties),with consideration of warm-up task specificity(specific vs.non-specific),temperature measurement method(muscle vs.skin),baseline temperatures,and subject-specific variables(training status and sex).Methods:A systematic search was conducted in PubMed/MEDLINE,Scopus,Web of Science,Cochrane,Embase,and ProQuest.Random-effects meta-analyses and meta-regressions were used to compute the effect sizes(ES)and 95%confidence intervals(95%CIs)to examine the effects of warm-up type,activation method,performance criterion,subject characteristics,and study design on temperature-related performance enhancement.Results:The search yielded 1272 articles,of which 33 met the inclusion criteria(n=921).Increasing temperature positively affected both voluntary(3.7%/℃±1.8%/℃(mean±SD),ES=0.28(95%CI:0.14 to 0.41))and evoked(3.2%/℃±1.5%/℃(mean±SD),ES=0.65(95%CI:0.29 to 1.00))rate-dependent contractile properties(dynamic,fast-velocity force production,and rate of force development(RFD))but not maximum force production(voluntary:-0.2%/℃±0.9%/℃(mean±SD),ES=0.08(95%CI:-0.05 to 0.22);evoked:-0.1%/℃±0.8%/℃(mean±SD),ES=-0.20(95%CI:-0.50 to 0.10)).Active warm-up did not induce greater enhancements in rate-dependent contractile properties(p=0.284),maximum force production(p=0.723),or overall function(pooled,p=0.093)than passive warm-up.Meta-regressions did not reveal a significant effect of study design,temperature measurement method,warm-up task specificity,training status,or sex on the effect of increasing temperature(p>0.05).Conclusion:Increasing muscle temperature significantly enhances rate-dependent contractile function(RFD and muscle power)but not maximum force in both evoked and voluntary contractions.In contrast to expectation,no effects of warm-up modality(active vs.passive)or temperature measurement method(muscle vs.skin)were detected,although insufficient data prevented robust sub-group analyses.展开更多
1.Background When searching for the term“muscle power”on Google Scholar,about 3.7 million hits come up in 60 ms,and for the past 3 years,there were approximately 225 yearly peer-reviewed publications dealing with mu...1.Background When searching for the term“muscle power”on Google Scholar,about 3.7 million hits come up in 60 ms,and for the past 3 years,there were approximately 225 yearly peer-reviewed publications dealing with muscle power.Muscle power has been used to assess and predict athletic performance,to determine muscle rehabilitation following injury or disease,to measure functional decline as occurs in aging,and many other topics.展开更多
It is a pleasure to contribute a commentary on the very interesting review by Dr.Orcioli-Silva and colleagues1 on the simultaneous measurements of cerebral cortex and muscle tissue oxygenation during exercise in healt...It is a pleasure to contribute a commentary on the very interesting review by Dr.Orcioli-Silva and colleagues1 on the simultaneous measurements of cerebral cortex and muscle tissue oxygenation during exercise in healthy adults using near-infrared spectroscopy(NIRS).The first NIRS measurements of the cerebral cortex and muscle were performed on humans in 19772 and 1982,3 respectively.展开更多
This review elucidates the impact of electrical stimulation(ES)and blood flow restriction(BFR)training on muscle function.ES induces a transformation in muscle fibers type by rearranging myosin heavy chain isoform pat...This review elucidates the impact of electrical stimulation(ES)and blood flow restriction(BFR)training on muscle function.ES induces a transformation in muscle fibers type by rearranging myosin heavy chain isoform patterns.Additionally,it influences muscle protein synthesis and degradation through specific signaling pathways such as protein kinase B/mechanistic target of rapamycin(Akt/mTOR),as well as via autophagy and the ubiquitin-proteasome system,thereby effectively maintaining muscle mass.BFR,on the other hand,restricts muscle blood flow,leading to metabolic products accumulation and localized hypoxia,which not only promotes the recruitment of fast-twitch fibers but also activates the mTOR signaling pathway,enhancing muscle protein synthesis.The combination of ES and BFR synergistically facilitates muscle protein synthesis through the mTOR pathway,thereby accelerating the recovery of muscle function following peripheral nerve injury.展开更多
Skeletal muscle dysfunction is a common extrapulmonary comorbidity of chronic obstructive pulmonary disease(COPD) and is associated with decreased quality-of-life and survival in patients. The autophagy lysosome pathw...Skeletal muscle dysfunction is a common extrapulmonary comorbidity of chronic obstructive pulmonary disease(COPD) and is associated with decreased quality-of-life and survival in patients. The autophagy lysosome pathway is one of the proteolytic systems that significantly affect skeletal muscle structure and function. Intriguingly, both promoting and inhibiting autophagy have been observed to improve COPD skeletal muscle dysfunction, yet the mechanism is unclear. This paper first reviewed the effects of macroautophagy and mitophagy on the structure and function of skeletal muscle in COPD, and then explored the mechanism of autophagy mediating the dysfunction of skeletal muscle in COPD. The results showed that macroautophagy-and mitophagy-related proteins were significantly increased in COPD skeletal muscle. Promoting macroautophagy in COPD improves myogenesis and replication capacity of muscle satellite cells, while inhibiting macroautophagy in COPD myotubes increases their diameters. Mitophagy helps to maintain mitochondrial homeostasis by removing impaired mitochondria in COPD. Autophagy is a promising target for improving COPD skeletal muscle dysfunction, and further research should be conducted to elucidate the specific mechanisms by which autophagy mediates COPD skeletal muscle dysfunction, with the aim of enhancing our understanding in this field.展开更多
文摘BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients.
基金Supported by Russian Science Foundation,No.19-76-30014.
文摘Skeletal muscle alterations(SMA)are increasingly recognized as both contributors and consequences of metabolic dysfunction-associated steatotic liver disease(MASLD),affecting disease progression and outcomes.Sarcopenia is common in patients with MASLD,with a prevalence ranging from 20%to 40%depending on the population and diagnostic criteria used.In advanced stages,such as metabolic dysfunction-associated steatohepatitis and fibrosis,its prevalence is even higher.Sarcopenia exacerbates insulin resistance,systemic inflammation,and oxidative stress,all of which worsen MASLD.It is an independent risk factor for fibrosis progression and poor outcomes including mortality.Myosteatosis refers to the abnormal accumulation of fat within muscle tissue,leading to decreased muscle quality.Myosteatosis is prevalent(>30%)in patients with MASLD,especially those with obesity or type 2 diabetes,although this can vary with the imaging techniques used.It reduces muscle strength and metabolic efficiency,further contributing to insulin resistance and is usually associated with advanced liver disease,cardiovascular complications,and lower levels of physical activity.Altered muscle metabolism,which includes mitochondrial dysfunction and impaired amino acid metabolism,has been reported in metabolic syndromes,including MASLD,although its actual prevalence is unknown.Altered muscle metabolism limits glucose uptake and oxidation,worsening hyperglycemia and lipotoxicity.Reduced muscle perfusion and oxygenation due to endothelial dysfunction and systemic metabolic alterations are common in MASLD associated with comorbidities,such as obesity,hypertension,and atherosclerosis.It decrea-ses the muscle capacity for aerobic metabolism,leading to fatigue and reduced physical activity in patients with MASLD,aggravating metabolic dysfunction.Various SMA in MASLD worsen insulin resistance and hepatic fat accumulation,may accelerate progression to fibrosis and cirrhosis,and increase the risk of cardiovascular disease and mortality.Management strategies for SMA include resistance training,aerobic exercise,and nutritional support(e.g.,high-protein diets,vitamin D,and omega-3 fatty acids),which are essential for mitigating skeletal muscle loss and improving outcomes.However,pharmacological agents that target the muscle and liver(such as glucagon-like peptide-1 receptor agonists)show promise but have not yet been approved for the treatment of MASLD.
基金supported by the National Key R&D Program of China(2023YFD1300103)the Science and Technology Plan Project of Yantai City(2023ZDCX024)+5 种基金the National Natural Science Foundation of China(32372852)the Science Fund for Distinguished Young Scholars of Shaanxi Province(2024JC-JCQN-30)Shaanxi Provincial Innovation Leadership Program in Sciences and Technologies for Young and Middle-aged Scientists(2023SR205)the China Agriculture Research System-beef(CARS-37)the Innovation Team of Cattle Industry in Technological System of Shandong Modern Agriculture Industry(SDAIT-09-03)the Key Research and Development Project in Shandong Province(Competitive Innovation Platform)(2022CXPT010).
文摘Background N^(6)-methyladenosine(m^(6)A)methylation is a key epigenetic modification that can modulate gene expression and strongly affect mammalian developmental processes.However,the genome-wide methylation of long non-coding RNAs(lncRNAs)and its implications for the development of skeletal muscle remain poorly understood.Bovine skeletal muscle samples from five developmental stages were analyzed in this study to establish lncRNA methylome and transcriptomic maps.Results Globally,59.67%of lncRNAs in skeletal muscle with m^(6)A modifications,and this percentage decreased progressively during development.lncRNA expression levels were positively associated with the number of m^(6)A peaks,with lncRNAs possessing 3 or more peaks showing significantly higher expression levels than those with 1 or 2 peaks.Specific lncRNAs involved in skeletal muscle development were identified through two analytical approaches.The first approach employed weighted gene co-expression network analysis(WGCNA)of transcriptomic data to identify correlations between annotated lncRNAs and growth-related traits,resulting in 21 candidate hub lncRNAs.The intersection of these 21 hub lncRNAs with 151 differentially methylated lncRNAs(DM-lncRNAs)identified 10 shared candidate lncRNAs.The second approach integrated MeRIP-seq and RNA-seq data to identify 36 lncRNAs that were both differentially m^(6)A modified and differentially expressed(dme-lncRNAs).GO and KEGG enrichment analyses of cis-target genes associated with these dme-lncRNAs identified eight candidate lncRNAs.Combining the results from the two approaches identified 16 key m^(6)A-modified lncRNAs likely involved in skeletal muscle development.Conclusions These findings highlight the regulatory and functional significance of dynamic lncRNA methylation in skeletal muscle development.
基金supported by grants from the Natural Science Foundation of Shandong Province,China(Grant Nos.:ZR2019ZD28 and ZR2022QH008)the National Natural Science Foundation of China(Grant Nos.:82270301 and 82200465)+1 种基金China Postdoctoral Science Foundation(Grant No.:2023M731842)Shandong Postdoctoral Science Foundation,China(Grant No.:SDCX-ZG-202203013).
文摘Vein graft(VG)failure(VGF)is associated with VG intimal hyperplasia,which is characterized by abnormal accumulation of vascular smooth muscle cells(VSMCs).Most neointimal VSMCs are derived from pre-existing VSMCs via a process of VSMC phenotypic transition,also known as dedifferentiation.There is increasing evidence to suggest that ginger or its bioactive ingredients may block VSMC dedifferentiation,exerting vasoprotective functions;however,the precise mechanisms have not been fully characterized.Therefore,we investigated the effect of ginger on VSMC phenotypic transition in VG remodeling after transplantation.Ginger significantly inhibited neointimal hyperplasia and promoted lumen(L)opening in a 3-month VG,which was primarily achieved by reducing ferroptotic stress.Ferroptotic stress is a pro-ferroptotic state.Contractile VSMCs did not die but instead gained a proliferative capacity and switched to the secretory type,forming neointima(NI)after vein transplantation.Ginger and its two main vasoprotective ingredients(6-gingerol and 6-shogaol)inhibit VSMC dedifferentiation by reducing ferroptotic stress.Network pharmacology analysis revealed that 6-gingerol inhibits ferroptotic stress by targeting P53,while 6-shogaol inhibits ferroptotic stress by targeting 5-lipoxygenase(Alox5),both promoting ferroptosis.Furthermore,both ingredients co-target peroxisome proliferator-activated receptor gamma(PPARγ),decreasing PPARγ-mediated nicotinamide adenine dinucleotide phosphate(NADPH)oxidase 1(Nox1)expression.Nox1 promotes intracellular reactive oxygen species(ROS)production and directly induces VSMC dedifferentiation.In addition,Nox1 is a ferroptosis-promoting gene that encourages ferroptotic stress production,indirectly leading to VSMC dedifferentiation.Ginger,a natural multi-targeted ferroptotic stress inhibitor,finely and effectively prevents VSMC phenotypic transition and protects against venous injury remodeling.
基金the National Natural Science Foundation of China(82471593 to J.M.32330047 and 31930057 to F.W.+2 种基金and 82071970 to Y.W.and 82072506 to Y.L.)the Science Fund for Distinguished Young Scholars of Hubei Province(2023AFA109 to Y.W.)Hubei Provincial Natural Science Foundation of China(2024AFB963 to Q.R.).
文摘The muscular system plays a critical role in the human body by governing skeletal movement,cardiovascular function,and the activities of digestive organs.Additionally,muscle tissues serve an endocrine function by secreting myogenic cytokines,thereby regulating metabolism throughout the entire body.Maintaining muscle function requires iron homeostasis.Recent studies suggest that disruptions in iron metabolism and ferroptosis,a form of iron-dependent cell death,are essential contributors to the progression of a wide range of muscle diseases and disorders,including sarcopenia,cardiomyopathy,and amyotrophic lateral sclerosis.Thus,a comprehensive overview of the mechanisms regulating iron metabolism and ferroptosis in these conditions is crucial for identifying potential therapeutic targets and developing new strategies for disease treatment and/or prevention.This review aims to summarize recent advances in understanding the molecular mechanisms underlying ferroptosis in the context of muscle injury,as well as associated muscle diseases and disorders.Moreover,we discuss potential targets within the ferroptosis pathway and possible strategies for managing muscle disorders.Finally,we shed new light on current limitations and future prospects for therapeutic interventions targeting ferroptosis.
基金funding support from Guiding Project of Scientific Research Plan of Education Department of Hubei Province and Wuhan Textile University School Fund(B)(k24016).
文摘Enhancing the firefighting protective clothing with exceptional thermal barrier and temperature sensing functions to ensure high fire safety for firefighters has long been anticipated,but it remains a major challenge.Herein,inspired by the human muscle,an anisotropic fire safety aerogel(ACMCA)with precise self-actuated temperature monitoring performance is developed by combining aramid nanofibers with eicosane/MXene to form an anisotropically oriented conductive network.By combining the two synergies of the negative temperaturedependent thermal conductive eicosane,which induces a high-temperature differential,and directionally ordered MXene that establishes a conductive network along the directional freezing direction.The resultant ACMCA exhibited remarkable thermoelectric properties,with S values reaching 46.78μV K^(−1)andκvalues as low as 0.048 W m^(−1)K^(−1)at room temperature.Moreover,the prepared anisotropic aerogel ACMCA exhibited electrical responsiveness to temperature variations,facilitating its application in intelligent temperature monitoring systems.The designed anisotropic aerogel ACMCA could be incorporated into the firefighting clothing as a thermal barrier layer,demonstrating a wide temperature sensing range(50-400℃)and a rapid response time for early high-temperature alerts(~1.43 s).This work provides novel insights into the design and application of temperature-sensitive anisotropic aramid nanofibers aerogel in firefighting clothing.
文摘BACKGROUND Skeletal muscle alterations(SMAs)are being increasingly recognized in patients with metabolic dysfunctionassociated steatotic liver disease(MASLD)and appear to be associated with deleterious outcomes in these patients.However,their actual prevalence and pathophysiology remain to be elucidated.AIM To determine the prevalence of SMAs and to assess the significance of circulating myokines as biomarkers in patients with MASLD.METHODS Skeletal muscle strength and muscle mass were measured in a cross-sectional study in a cohort of 62 patients fulfilling MASLD criteria,recruited from the outpatient clinics of a tertiary level hospital.The degree of fibrosis and liver steatosis was studied using abdominal ultrasound and transitional elastography.Anthropometric and metabolic characteristics as well as serum levels of different myokines were also determined in the MASLD cohort.Statistical analysis was performed comparing results according to liver fibrosis and steatosis.RESULTS No significant differences were found in both skeletal muscle strength and skeletal muscle mass in patients with MASLD between different stages of liver fibrosis.Interestingly,serum levels of fibroblast growth factor-21(FGF21)were significantly higher in patients with MASLD with advanced hepatic fibrosis(F3-F4)than in those with lower fibrosis stages(F0-F2)(197.49±198.27 pg/mL vs 95.62±83.67 pg/mL;P=0.049).In addition,patients with MASLD with severe hepatosteatosis(S3)exhibited significantly higher serum levels of irisin(1116.87±1161.86 pg/mL)than those with lower grades(S1-S2)(385.21±375.98 pg/mL;P=0.001).CONCLUSION SMAs were uncommon in the patients with MASLD studied.Higher serum levels of irisin and FGF21 were detected in patients with advanced liver steatosis and fibrosis,respectively,with potential implications as biomarkers.
基金Supported by NSFC(No.12171062)the Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-JQX0004)+1 种基金the Chongqing Talent Support Program(No.cstc2024ycjh-bgzxm0121)Science and Technology Project of Chongqing Education Committee(No.KJZD-M202300503)。
文摘The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.
文摘BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing.
文摘Background: Aging-induced cardiac hypertrophy and reduced skeletal muscle strength contribute to increased disease risk and life burden in the elderly. FNDC5 acts as a protective muscle factor in both cardiac and skeletal muscle. This study aims to examine the relationship between cardiac FNDC5 and aging-related cardiac hypertrophy and decreased skeletal muscle strength. Methods: Male young C57BL/6 mice (5 months old, n = 6) and aged mice (21 months old, n = 6) were utilized in the study and housed in a specific pathogen-free (SPF) environment. Prior to the experiment, grip strength tests were performed on the mice, and heart tissues were collected for morphological analysis, including the assessment of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) and fibronectin type III-containing structural domain 5 (FNDC5) protein levels. Furthermore, myosin heavy chain II (MyHC II), skeletal muscle-specific transcription factor (MyoD), muscle RING-finger protein-1 (MuRF1), and FNDC5 levels were evaluated in the quadriceps muscle. The correlations between heart weight and FNDC5 expression levels, as well as skeletal muscle indices in the mice, were subsequently analyzed. Result: Aging leads to cardiac hypertrophy and reduced expression of PGC-1α and FNDC5 proteins. Concurrently, there is a decline in the strength of skeletal muscle, along with decreased expression of MyHC II and increased expression of MURF1 and MyoD. Correlation analysis demonstrated strong positive associations between myocardial FNDC5 protein levels and limb grip strength, as well as MyHC II, and strong negative associations with MyoD and MuRF1. Conclusion: There may be a significant association between aging-induced cardiac hypertrophy and decreased skeletal muscle strength, with FNDC5 potentially playing a crucial role as a regulatory molecule facilitating communication between the heart and skeletal muscle.
文摘The“longevity protein”SIRT5 could hold the key to delaying age-related muscle decline.A study led by researchers from the Institute of Zoology(IOZ)of the Chinese Academy of Sciences and Capital Medical University in Beijing reveals that SIRT5 mitigates skeletal muscle aging by blocking pro-inflammatory pathways.Published in Nature Metabolism on March 14,2025,the work identifies SIRT5’s interaction with protein kinase TBK1 as critical to preserving muscle mass and function.
文摘This study examined the repeated bout effect(RBE)on muscle damage markers following two bouts of neuromuscular electrical stimulation(NMES)in untrained individuals.Following familiarization,participants received 45 consecutive NMES to the biceps brachii at an intensity that produced low evoked force for the elbow flexors.Muscle damage markers(maximal voluntary isometric contraction[MVIC],elbow range of motion[ROM],muscle soreness via visual analogue scale[VAS]scores,pressure pain threshold[PPT],and muscle thickness)were measured before(PRE),after(POST),1 day after(24 POST),and 2 days after(48 POST)NMES.Following 1 week of rest,procedures were replicated.Separate repeated measures two-way ANOVAs examined each measure.There were no interactions or bout main effects for MVIC or ROM.Time main effects indicated PRE MVIC was greater than POST(p=0.002)and 24-POST(p=0.024),and PRE ROM was greater than POST(p=0.036).There was no interaction for muscle thickness.Respective time and bout main effects indicated muscle thickness at PRE was less than POST(p=0.017),and second-bout muscle thickness(p=0.050)was less compared to the initial-bout.For PPT,there was an interaction(p=0.019).Initial-bout PRE PPT was less than POST(p=0.033).Initial-bout 48-POST PPT was less than second-bout 48-POST(p=0.037).There was a significant interaction for VAS(p=0.009).Initial-bout PRE VAS was less than POST(p=0.033)and 24-POST(p=0.015).Initial-bout POST and 24-POST VAS were greater than second-bout POST(p=0.023)and 24-POST(p=0.006),respectively.The results support RBE on muscle damage markers related to inflammation,but not MVIC and ROM.
基金supported by funding from the National Natural Science Foundation of China(82272478,82002330,82202728)the National Key R&D Program of China(No.2022YFF1100100)the Natural Science Foundation of Beijing(L222086).
文摘Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through microbiome modulation,their therapeutic impact on gut dysfunction-induced bone and muscle loss remains to be elucidated.Employing dextran sulfate sodium(DSS)-induced gut dysfunction model and wide-spectrum antibiotics(ABX)-treated mice model,our study revealed that gut dysfunction instigates muscle and bone loss,accompanied by microbial imbalances.Importantly,Bifidobacterium animalis subsp.lactis A6(B.lactis A6)administration significantly ameliorated muscle and bone loss by modulating gut microbiota composition and enhancing butyrate-producing bacteria.This intervention effectively restored depleted butyrate levels in serum,muscle,and bone tissues caused by gut dysfunction.Furthermore,butyrate supplementation mitigated musculoskeletal loss by repairing the damaged intestinal barrier and enriching beneficial butyrate-producing bacteria.Importantly,butyrate inhibited the NF-κB pathway activation,and reduced the secretion of corresponding inflammatory factors in T cells.Our study highlights the critical role of dysbiosis in gut dysfunction-induced musculoskeletal loss and underscores the therapeutic potential of B.lactis A6.These discoveries offer new microbiome directions for translational and clinical research,providing promising strategies for preventing and managing musculoskeletal diseases.
文摘Sarcomerogenesis,the addition of serial sarcomeres in skeletal muscle myofibrils and fibres,is a natural occurrence during growth and maturation of animals,including humans.However,the detailed mechanisms that allow for sarcomerogenesis are not fully understood.In some diseases,such as cerebral palsy in children,sarcomerogenesis appears to be inhibited or at least reduced,1,2 often causing severe restrictions in muscle and joint function.
基金supported by the funded project(HYZHX M05005)in the field of space medical experiments of manned spaceflight engineering.
文摘Objective:To evaluate the efficacy and safety of transcutaneous electrical acupoint stimulation(TEAS)for muscle atrophy in patients with immobilization after surgical fixation of foot and ankle fractures.Methods:This was a two-arm randomized controlled trial wherein 80 patients were recruited and divided into control(n=40)and intervention(n=40)groups.The control group received conventional orthopedic treatment,whereas the intervention group received TEAS and conventional treatment.The intervention group received TEAS 3 times a week for 30 min each time for 8 weeks.The primary out-comes were muscle thickness(MT)and cross-sectional area(CSA)of the rectus femoris and gastroc-nemius muscles,whereas the secondary outcome measure was echo intensity(EI).Data were collected before the fixation operations(baseline assessment)and 4 and 8 weeks after intervention.Results:Compared with baseline,the MT and CSA were reduced in both groups by the end of treatment,whereas EI increased in both groups.At week 4,the reduction in the rectus femoris CSA in the inter-vention group was significantly lower than that in the control group(P=0.02);however,the between-group differences in the MT and EI(all P>0.05)were not significant.No serious adverse events were observed in either group.Conclusion:Our study showed that TEAS can improve muscle atrophy by attenuating the decline in the muscle CSA.Because this was only a pilot trial,subsequent studies will need longer follow-ups and larger sample sizes.
文摘Background:While muscle contractility increases with muscle temperature,there is no consensus on the best warm-up protocol to use before resistance training or sports exercise due to the range of possible warm-up and testing combinations available.Therefore,the objective of the current study was to determine the effects of different warm-up types(active,exercise-based vs.passive)on muscle function tested using different activation methods(voluntary vs.evoked)and performance test criteria(maximum force vs.rate-dependent contractile properties),with consideration of warm-up task specificity(specific vs.non-specific),temperature measurement method(muscle vs.skin),baseline temperatures,and subject-specific variables(training status and sex).Methods:A systematic search was conducted in PubMed/MEDLINE,Scopus,Web of Science,Cochrane,Embase,and ProQuest.Random-effects meta-analyses and meta-regressions were used to compute the effect sizes(ES)and 95%confidence intervals(95%CIs)to examine the effects of warm-up type,activation method,performance criterion,subject characteristics,and study design on temperature-related performance enhancement.Results:The search yielded 1272 articles,of which 33 met the inclusion criteria(n=921).Increasing temperature positively affected both voluntary(3.7%/℃±1.8%/℃(mean±SD),ES=0.28(95%CI:0.14 to 0.41))and evoked(3.2%/℃±1.5%/℃(mean±SD),ES=0.65(95%CI:0.29 to 1.00))rate-dependent contractile properties(dynamic,fast-velocity force production,and rate of force development(RFD))but not maximum force production(voluntary:-0.2%/℃±0.9%/℃(mean±SD),ES=0.08(95%CI:-0.05 to 0.22);evoked:-0.1%/℃±0.8%/℃(mean±SD),ES=-0.20(95%CI:-0.50 to 0.10)).Active warm-up did not induce greater enhancements in rate-dependent contractile properties(p=0.284),maximum force production(p=0.723),or overall function(pooled,p=0.093)than passive warm-up.Meta-regressions did not reveal a significant effect of study design,temperature measurement method,warm-up task specificity,training status,or sex on the effect of increasing temperature(p>0.05).Conclusion:Increasing muscle temperature significantly enhances rate-dependent contractile function(RFD and muscle power)but not maximum force in both evoked and voluntary contractions.In contrast to expectation,no effects of warm-up modality(active vs.passive)or temperature measurement method(muscle vs.skin)were detected,although insufficient data prevented robust sub-group analyses.
文摘1.Background When searching for the term“muscle power”on Google Scholar,about 3.7 million hits come up in 60 ms,and for the past 3 years,there were approximately 225 yearly peer-reviewed publications dealing with muscle power.Muscle power has been used to assess and predict athletic performance,to determine muscle rehabilitation following injury or disease,to measure functional decline as occurs in aging,and many other topics.
文摘It is a pleasure to contribute a commentary on the very interesting review by Dr.Orcioli-Silva and colleagues1 on the simultaneous measurements of cerebral cortex and muscle tissue oxygenation during exercise in healthy adults using near-infrared spectroscopy(NIRS).The first NIRS measurements of the cerebral cortex and muscle were performed on humans in 19772 and 1982,3 respectively.
文摘This review elucidates the impact of electrical stimulation(ES)and blood flow restriction(BFR)training on muscle function.ES induces a transformation in muscle fibers type by rearranging myosin heavy chain isoform patterns.Additionally,it influences muscle protein synthesis and degradation through specific signaling pathways such as protein kinase B/mechanistic target of rapamycin(Akt/mTOR),as well as via autophagy and the ubiquitin-proteasome system,thereby effectively maintaining muscle mass.BFR,on the other hand,restricts muscle blood flow,leading to metabolic products accumulation and localized hypoxia,which not only promotes the recruitment of fast-twitch fibers but also activates the mTOR signaling pathway,enhancing muscle protein synthesis.The combination of ES and BFR synergistically facilitates muscle protein synthesis through the mTOR pathway,thereby accelerating the recovery of muscle function following peripheral nerve injury.
基金supported by the National Natural Science Foundation of China(No.82172551)the Health Discipline Leader Project of Shanghai Municipal Health Commission(No.2022XD044),China.
文摘Skeletal muscle dysfunction is a common extrapulmonary comorbidity of chronic obstructive pulmonary disease(COPD) and is associated with decreased quality-of-life and survival in patients. The autophagy lysosome pathway is one of the proteolytic systems that significantly affect skeletal muscle structure and function. Intriguingly, both promoting and inhibiting autophagy have been observed to improve COPD skeletal muscle dysfunction, yet the mechanism is unclear. This paper first reviewed the effects of macroautophagy and mitophagy on the structure and function of skeletal muscle in COPD, and then explored the mechanism of autophagy mediating the dysfunction of skeletal muscle in COPD. The results showed that macroautophagy-and mitophagy-related proteins were significantly increased in COPD skeletal muscle. Promoting macroautophagy in COPD improves myogenesis and replication capacity of muscle satellite cells, while inhibiting macroautophagy in COPD myotubes increases their diameters. Mitophagy helps to maintain mitochondrial homeostasis by removing impaired mitochondria in COPD. Autophagy is a promising target for improving COPD skeletal muscle dysfunction, and further research should be conducted to elucidate the specific mechanisms by which autophagy mediates COPD skeletal muscle dysfunction, with the aim of enhancing our understanding in this field.
