Depressive disorder is a prevalent mental illness characterized by pronounced and enduring symptoms of depression and cognitive impairment. The escalating pressures of modern society have led to a corresponding rise in the number of depressive disorder patients, particularly those exposed to adverse social, economic, political, and environmental factors which exacerbate the risk of this disorder. The pathogenesis of depressive disorder is multifaceted, encompassing oxidative stress, neuroplasticity alterations, neuroinflammation, neurotransmitter system imbalances, and intestinal microecological disruptions, among others. Clinically, conventional antidepressants are primarily predicated on the monoamine neurotransmitter hypothesis. This theory posits that depressive disorder can be ameliorated by regulating the levels of neurotransmitters within the body through a singular mechanism. However, the complex and multifaceted pathogenesis of depressive disorder results in limited selectivity for these drugs. Mitogen-activated protein kinase (MAPK) is a conserved serine/threonine kinase that plays a crucial role in various cellular physiological and pathological processes, including cell growth, differentiation, stress adaptation, and inflammatory response. It is instrumental in maintaining cellular homeostasis and regulating cellular responses. Numerous studies indicate that MAPK is involved in the pathogenesis and progression of depressive disorder through various pathogenesis. However, what deserves attention is that the interaction between the pathogenesis and dynamics of regulatory process remains unclear. Modulating MAPK has been shown to influence the onset and progression of depressive disorder, though the precise mechanism remains elusive. Within the MAPK family, aberrant activity of extracellular signal-regulated kinase (ERK) can damage hippocampal neurons and overactivate microglia, precipitating depressive disorder. Excessive activation of c-Jun N-terminal kinase (JNK) results in heightened neuronal apoptosis in the hippocampus and prefrontal cortex, and suppresses the expression of neurotrophic factors. p38, a key regulator in inflammatory reactions, can induce neuroinflammation when overactive, leading to depressive disorder. ERK, JNK, and p38 sub-pathways do not function in isolation but rather interact synergistically and/or antagonistically through shared activators and common target molecules. Consequently, these sub-pathways form a complementary and coordinated regulatory network. In addition, MAPK family members can jointly influence the process of depressive disorder by sharing upstream factors and regulating common downstream targets, and there is a lack of identification of their markers and screening for subgroups. The collective abnormal activities of these MAPK family members illuminate the underlying mechanisms of depressive disorder, suggesting that MAPK could serve as a potential therapeutic target for this disorder. As for the study of ERK, different models of depressive disorder have contradictory effects on its activity. The primary cause of these differences can be attributed to the distinct pathological environments utilized in the creation of depressive disorder models. In the future, it is suggested that we use the inducement of depressive disorder as a modeling standard to accurately simulate the onset of depressive disorder to carry out accurate treatment according to the causes of depressive disorder. Research shows that classic clinical drugs, novel MAPK inhibitors and certain traditional Chinese medicines can prevent and treat depressive disorder by regulating the MAPK signaling pathway. Research on MAPK remains limited, particularly concerning the permeability and cellular specificity across the blood-brain barrier and the identification of objective predictive markers. Although inhibitors face challenges, they also possess significant advantages and developmental potential. This paper systematically summarizes the current status of MAPK in the treatment of depressive disorder, in order to provide insights for researching the pathogenesis of depressive disorder and developing new antidepressant drugs.

Depressive disorder is a prevalent mental illness characterized by pronounced and enduring symptoms of depression and cognitive impairment. The escalating pressures of modern society have led to a corresponding rise in the number of depressive disorder patients, particularly those exposed to adverse social, economic, political, and environmental factors which exacerbate the risk of this disorder. The pathogenesis of depressive disorder is multifaceted, encompassing oxidative stress, neuroplasticity alterations, neuroinflammation, neurotransmitter system imbalances, and intestinal microecological disruptions, among others. Clinically, conventional antidepressants are primarily predicated on the monoamine neurotransmitter hypothesis. This theory posits that depressive disorder can be ameliorated by regulating the levels of neurotransmitters within the body through a singular mechanism. However, the complex and multifaceted pathogenesis of depressive disorder results in limited selectivity for these drugs. Mitogen-activated protein kinase (MAPK) is a conserved serine/threonine kinase that plays a crucial role in various cellular physiological and pathological processes, including cell growth, differentiation, stress adaptation, and inflammatory response. It is instrumental in maintaining cellular homeostasis and regulating cellular responses. Numerous studies indicate that MAPK is involved in the pathogenesis and progression of depressive disorder through various pathogenesis. However, what deserves attention is that the interaction between the pathogenesis and dynamics of regulatory process remains unclear. Modulating MAPK has been shown to influence the onset and progression of depressive disorder, though the precise mechanism remains elusive. Within the MAPK family, aberrant activity of extracellular signal-regulated kinase (ERK) can damage hippocampal neurons and overactivate microglia, precipitating depressive disorder. Excessive activation of c-Jun N-terminal kinase (JNK) results in heightened neuronal apoptosis in the hippocampus and prefrontal cortex, and suppresses the expression of neurotrophic factors. p38, a key regulator in inflammatory reactions, can induce neuroinflammation when overactive, leading to depressive disorder. ERK, JNK, and p38 sub-pathways do not function in isolation but rather interact synergistically and/or antagonistically through shared activators and common target molecules. Consequently, these sub-pathways form a complementary and coordinated regulatory network. In addition, MAPK family members can jointly influence the process of depressive disorder by sharing upstream factors and regulating common downstream targets, and there is a lack of identification of their markers and screening for subgroups. The collective abnormal activities of these MAPK family members illuminate the underlying mechanisms of depressive disorder, suggesting that MAPK could serve as a potential therapeutic target for this disorder. As for the study of ERK, different models of depressive disorder have contradictory effects on its activity. The primary cause of these differences can be attributed to the distinct pathological environments utilized in the creation of depressive disorder models. In the future, it is suggested that we use the inducement of depressive disorder as a modeling standard to accurately simulate the onset of depressive disorder to carry out accurate treatment according to the causes of depressive disorder. Research shows that classic clinical drugs, novel MAPK inhibitors and certain traditional Chinese medicines can prevent and treat depressive disorder by regulating the MAPK signaling pathway. Research on MAPK remains limited, particularly concerning the permeability and cellular specificity across the blood-brain barrier and the identification of objective predictive markers. Although inhibitors face challenges, they also possess significant advantages and developmental potential. This paper systematically summarizes the current status of MAPK in the treatment of depressive disorder, in order to provide insights for researching the pathogenesis of depressive disorder and developing new antidepressant drugs.

ObjectiveTo address the limitations of the current quality standard for Polygalae Radix（PR）， which relies on a single component for quality assessment and struggles to holistically control its intrinsic quality， by constructing a comprehensive quality evaluation system integrating "macro-characterization of chemical profile， synchronous quantification of multiple index components， and quantitative analysis of multi-components by single marker（QAMS） for key component groups". This study aims to facilitate the scientific revision of the quality standard for PR. MethodsHigh performance liquid chromatography（HPLC） characteristic chromatograms were established for 11 batches of PR medicinal materials（YZ）， 10 batches of PR decoction pieces（YP）， and 10 batches of licorice-processed PR decoction pieces（ZYZ）， followed by similarity evaluation and identification of common peaks. HPLC-QAMS was developed for xanthones（sibiricaxanthone B， polygalaxanthone Ⅺ， polygalaxanthone Ⅲ） in the characteristic chromatograms. Simultaneously， the external standard method（ESM） was used to determine the contents of the corresponding xanthones and 3，6'-disinapoyl sucrose in YZ， YP， and ZYZ， followed by multivariate statistical analysis and Spearman correlation analysis. ResultsThe similarity between the characteristic chromatograms of 31 batches of PR samples and the reference chromatogram was>0.9. A total of 13 common peaks were identified， and 10 of these peaks were characterized through reference standard comparison. The successfully constructed QAMS method showed that the relative correction factors（RCFs） of sibiricaxanthone B and polygalaxanthone Ⅺ to polygalaxanthone Ⅲ were 0.76 and 0.88， and their relative retention times（RRTs） were 0.85 and 0.97， respectively. The results calculated by the QAMS method showed no significant difference from those obtained by the ESM. According to the limit standard for polygalaxanthone Ⅲ in the 2020 edition of the Pharmacopoeia of the People's Republic of China（hereinafter referred to as the Chinese Pharmacopoeia）， the pass rate of 31 batches of samples was only 19.35%. Multivariate statistical analysis indicated certain compositional differences between different batches of YZ and YP， as well as between YP and ZYZ， with 3，6'-disinapoyl sucrose identified as the main differentiating component. Furthermore， correlation analysis revealed that the content of polygalaxanthone Ⅲ was positively correlated with the contents of sibiricaxanthone B and polygalaxanthone Ⅺ， but showed no association with the content of 3，6'-disinapoyl sucrose. ConclusionIt is recommended that the content limit for polygalaxanthone Ⅲ in YZ，YP and ZYZ be revised to not less than 0.07%， or the total content of polygalaxanthone Ⅲ， sibiricaxanthone B and polygalaxanthone Ⅺ be not less than 0.18%. The newly established triple quality control model of "holistic control via characteristic chromatograms， precise quantification of oligosaccharide esters， and efficient detection of xanthones by QAMS" provides a systematic and precise solution for quality evaluation of PR and similar Chinese herbal medicines.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To examine the diagnosis and treatment of disseminated infection caused by Enterocytozoon bieneusi in a child with leukemia and improve the awareness of the pathogen in clinical and laboratory practice.Methods A case of disseminated infection caused by Enterocytozoon bieneusi in a child with leukemia in Shanghai Children's Hospital was retrospectively analyzed,including diagnosis and treatment details.Similar cases were identified from PubMed,Wanfang Data,VIP,and CNKI databases since database establishment until June 30,2024,using search terms"Enterocytozoon bieneusi".The relevant literature was reviewed.Results This child had acute lymphoblastic leukemia as the underlying disease and was admitted to hospital for antimicrobial treatment due to fever and abdominal discomfort.The case was considered bacterial infection complicated with Enterocytozoon bieneusi infection,confirmed by detection of Klebsiella pneumoniae in blood and detection of Enterocytozoon bieneusi in blood and ascites by metagenomic next-generation sequencing(mNGS).The treatment was switched to tigecycline plus trimethoprim-sulfamethoxazole at a sufficient dose,which resulted in resolution of symptoms.Six months later,the patient suffered from acute lymphoblastic leukemia and bone marrow depression,Enterocytozoon bieneusi disseminated infection,septic shock.Her family gave up treatment and the child died.Literature review indicated that most patients infected with Enterocytozoon bieneusi had underlying conditions such as organ transplantation,AIDS,and leukemia associated with poor immunity.The onset symptoms are diarrhea,abdominal discomfort,and fever.Enterocytozoon bieneusi was detected by using methods such as modified Masson's trichrome stain,fluorescent calcofluor white staining,molecular detection techniques,and immunofluorescence.The patients were treated with drugs such as albendazole,nitazoxanide,fumagillin,and trimethoprim-sulfamethoxazole.Conclusions Enterocytozoon bieneusi is an opportunistic pathogenic fungus that infects immunocompromised patients and can cause abdominal discomfort,diarrhea,fever,and even disseminated infection and death.Conventional laboratory methods cannot culture Enterocytozoon bieneusi.Molecular detection techniques can be used to identify the pathogen early.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Creutzfeldt-Jakob disease(CJD)is a rare neurodegenerative disorder characterized by abnor-malities in the prion protein(PrP),the most common form of human prion disease.Although Genome-Wide Association Studies(GWAS)have identified numerous risk genes for CJD,the mechanisms under-lying these risk loci remain poorly understood.This study aims to elucidate novel genetically prioritized candidate proteins associated with CJD in the human brain through an integrative analytical pipeline.Uti-lizing datasets from Protein Quantitative Trait Loci(pQTL)(NpQTL1=152,NpQTL2=376),expres-sion QTL(eQTL)(N=452),and the CJD GWAS(NCJD=4 110,NControls=13 569),we imple-mented a systematic analytical pipeline.This pipeline included Proteome-Wide Association Study(PWAS),Mendelian randomization(MR),Bayesian colocalization,and Transcriptome-Wide Associa-tion Study(TWAS)to identify novel genetically prioritized candidate proteins implicated in CJD patho-genesis within the brain.Through PWAS,we identified that the altered abundance of six brain proteins was significantly associated with CJD.Two genes,STX6 and PDIA4,were established as lead causal genes for CJD,supported by robust evidence(False Discovery Rate＜0.05 in MR analysis;PP4/(PP3+PP4)≥0.75 in Bayesian colocalization).Specifically,elevated levels of STX6 and PDIA4 were asso-ciated with an increased risk of CJD.Additionally,TWAS demonstrated that STX6 and PDIA4 were asso-ciated with CJD at the transcriptional level.

This study was aimed at providing basic data for the control and prevention of Yersinia enterocolitica(Ye)infections.Ye isolates from stool samples collected from patients with diarrhea in a Beijing district between January 2019 and June 2024 were studied.Basic patient information and stool samples were collected,and quantitative polymerase chain reaction(qPCR)was applied to enriched cultures.Further analyses included virulence gene detection,whole-genome sequencing,and drug resistance detection.The detection rate of Ye was 0.76%(11/1 439),according to culture methods,thus yielding 12 Ye strains from distinct patients:11 isolated during the study period and 1 from 2017.The 12 Ye positive patients were 6-41 years of age,and their clinical presentations predominantly featured watery stools(66.67%,8/12)and loose stools(33.33%,4/12).The frequencies of nausea,vomiting,and fever were 41.67%(5/12),41.67%(5/12),and 8.33%(1/12),respectively.The drug resistance rates of Ye to TET,AMP,and NAL were 50.00%(6/12),33.33%(4/12),and 25.00%(3/12),respectively.One Ye strain exhibited multidrug resistance to ETP,MEM,TET,CIP,NAL,and AMP.According to qPCR detection of five common virulence genes,two Ye strains were identified as ystA+/ystB-type(ystA+/ystB-/ail+/yadA+/virF+),whereas ten strains were identified as ystA-/ystB+type(ystA-/ystB+/ail-/yadA-/virF-).VFDB database analysis based on genome sequences indicated that 12 Ye strains carried an average of 11 key virulence genes associated with adhesion,invasion,protease activity,and flagellar movement,and predicted 106 virulence genes and 12 virulence gene profiles.Only the two ystA+/ystB-Ye strains contained elements related to the TTSS and ABC transporter function.Detection of ystA-/ystB+Ye in stool isolation and culture of diarrhea cases might potentially have been missed in some cases,thus highlighting the importance of fluorescence PCR screening of fecal growth solutions to enhance isolation efficiency.Moreover,our findings revealed the genetic diversity of Ye isolated from diarrhea cases,thereby indicating the presence of multiple types of virulence genes within this pathogen.

Objective To explore the effect of aerobic exercise on sarcopenia in CT26 tumor mice through the gut microbiota-skeletal muscle axis and its potential mechanism.Methods Forty-eight SPF BALB/c male mice aged 8 weeks were randomly divided into a normal control group(group NC,n=12),a normal control+aerobic exercise group(group NA,n=12),a CT26 tumor-associated sarco-penia group(group TS,n=12)and a CT26 tumor-associated sarcopenia+aerobic exercise group(group TSA,n=12).After a 2-week adaptive exercise period,CT26 cell suspension(0.2 mL,1×107 cells/mL)was subcutaneously injected into the dorsal region of mice in group TS and group TSA,while group NC and group NA were inoculated with 0.2 mL normal saline.One day later,group NA and group TSA underwent a 4-week aerobic treadmill running intervention(14 m/min,60 min/day,6 days/week).If a mouse failed to complete the target intensity on a given day,its running speed was reduced by 20%the following day.Moreover,group NA and group TSA received no exercise interven-tion.General health status of all groups was monitored throughout the study.The forelimb gripping force,rotarod walking time and the cross-sectional area of gastrocnemius muscle fibers were measured.Moreover,the ultrastructural changes of gastrocnemius were observed by transmission electron micro-scope,while the cecum contents were observed by 16S rRNA sequencing.Meanwhile,the pathological morphological changes of small intestine wall were observed using HE,while the contents of tumor ne-crosis factor-α(TNF-α),interleukin-6(IL-6),interleukin-1β(IL-1β)and lipopoly saccharide(LPS)of serum and gastrocnemius muscle were determined by using ELISA.Moreover,small intestine zonula occludens-1(ZO-1),Occludin and muscle ring finger 1(MuRF1),muscle atrophy F-box(MAF-bx),Toll-like receptor 4(TLR4)/myeloid differentiation factor 8(MyD88)/nuclear transcription factor-κB(NF-κB)signal pathway related proteins expression levels of gastrocnemius muscle,as well as muscle ring finger 1(MuRF1)and muscle atrophy F-box(MAF-bx)were detected using Western blot.Results(1)Subcutaneous tumors were prominent in group TS.The forelimb gripforce,wet weight and cross-sectional area of gastrocnemius,and rotarod walking time in group TS at the 5th and 6th weekends were significantly lower than group NC(P<0.01),while the relative expression levels of MuRF1 and MAF-bx proteins in the gastrocnemius muscle in group TS were significantly higher than the latter group(P<0.05,P<0.01).Moreover,transmission electron microscopy revealed sparse and dis-organized muscle fiber arrangement in group TS,with visible Z-lines but indistinct M-lines,as well as shortened,poorly defined,and thin sarcomeres.(2)The group TSA exhibited significantly higher α-diversity indices(Shannon,Chao1,and Observed species)in gut microbiota compared to group TS(P<0.05,P<0.01,P<0.05),while the β-diversity differed to some extent between the two groups.At phylum level,the F/B ratio was lower in group NA than that group NC,with that of group TSA low-er than group TS.At genus level,the relative abundances of Muribaculaceae,Bacteroides,Roseburia,and Alistipes in group NA were higher than group NC,and those of Alloprevotellaand Helicobacter were significantly lower,while those of Muribaculaceae,Lachnospiraceae_NK4A136_group,Roseburia,Bacteroides,Lachnospiraceae_UCG-001 of group TSA were significantly higher than group TS.Nota-bly,Roseburia and Alistipes were the most significantly enriched genera in group TSA and group TS(LDA score>4 for both).(3)The inflammatory cells of the small intestine wall in group TSA signifi-cantly reduced than those in group TS(P<0.05).Moreover,the expression level of ZO-1 proteins in the small intestine wall were significantly higher in group NA than group NC,and that of ZO-1 and Occludin proteins in the small intestine wall was significantly higher in group TSA than those in group TS(P<0.05).(4)The group NA exhibited significantly lower LPS concentrations in the gastrocne-mius muscle compared to group NC(P<0.05).Similarly,the group TSA showed reduced LPS levels in both serum and gastrocnemius compared to group TS(P<0.05).The relative protein expression of p-IκBα and p-NF-κB p65 significantly decreased in group TSA compared to group TS(P<0.05).The group TS displayed elevated concentrations of pro-inflammatory cytokines(TNF-α,IL-1β)in serum and gastrocnemius compared to group NC(P<0.01,P<0.05).The group TSA demonstrated significantly lower levels of TNF-α and IL-6 in these tissues in comparison with group TS(P<0.05,P<0.01).Conclusion Aerobic exercise can improve gut microbiota α diversity,adjusting its composition,improv-ing intestinal mucosal barrier function,reducing the LPS-induced pro-inflammatory response,and delay-ing skeletal muscle atrophy.The underlying mechanism may involve down regulation of TLR4/MyD88/NF-κB signaling in skeletal muscle,which has a positive effect on Gut-Muscle Axis.