ObjectiveThe exacerbating trend of global population aging poses profound socioeconomic and public health challenges, making the comprehensive elucidation of biological aging mechanisms and the discovery of effective anti-aging interventions an urgent priority in the life sciences. Based on our previous serum metabolomics findings that dimethylglycine, an intermediate metabolite of amino acid metabolism naturally present in the human body, was significantly enriched in the serum of longevity families, this study aimed to systematically investigate the anti-aging effects of dimethylglycine both in living organisms and in controlled laboratory environments, and to preliminarily elucidate its underlying molecular mechanisms. While existing literature indicates that dimethylglycine possesses antioxidant and immunomodulatory properties, its direct anti-aging efficacy and the specific molecular pathways through which it operates remain largely unexplored. MethodsTo comprehensively evaluate the anti-aging properties of dimethylglycine, we utilized replicative senescent human embryonic lung fibroblasts, specifically the WI-38 cell line, as an experimental model in a controlled laboratory environment. Cell viability and safety were thoroughly assessed using Cell Counting Kit-8 and lactate dehydrogenase release assays across various concentrations of dimethylglycine. The impact of dimethylglycine on cellular senescence phenotypes, oxidative stress, and proliferative capacity was evaluated via senescence-associated beta-galactosidase staining, reactive oxygen species fluorescence detection, and 5-ethynyl-2'-deoxyuridine incorporation assays. Furthermore, the molecular alterations of senescence-associated secretory phenotype factors and core senescence signaling pathways were quantified using quantitative reverse transcription polymerase chain reaction for the messenger RNA levels of interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1, and enzyme-linked immunosorbent assay for the measurement of p16 and p21 protein expression levels. For the living organism model, the wild-type nematode Caenorhabditis elegans was used to evaluate systemic physiological effects. We conducted a comprehensive lifespan analysis at 20°C, heat stress resistance survival assays at 35℃, senescence-associated beta-galactosidase staining, lipofuscin accumulation tracking, intracellular reactive oxygen species measurement, and Oil Red O staining to ascertain systemic lipid accumulation. Additionally, network pharmacology bioinformatics tools, including PharmMapper and STRING databases, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were utilized to predict target pathways, alongside highly detailed molecular docking simulations utilizing SwissDock and Protein-Ligand Interaction Profiler to examine interactions with the cytochrome P450 family 2 subfamily C member 9 protein. ResultsThe experimental outcomes robustly demonstrate the potent anti-aging capabilities of dimethylglycine. At the cellular level, toxicity analyses firmly confirmed that dimethylglycine is highly safe; continuous treatment with 50 mol/L and 70 mol/L of dimethylglycine for 5 d did not induce any cellular membrane damage or cytotoxicity, but rather actively promoted cellular proliferation. Utilizing the optimal standardized concentration of 50 mol/L, dimethylglycine treatment significantly ameliorated senescent phenotypic markers in human embryonic lung fibroblasts, which was evidenced by a drastic and highly significant reduction in the senescence-associated beta-galactosidase positive cell percentage (P<0.000 1) and intracellular reactive oxygen species levels (P<0.000 1), alongside a marked increase in the 5-ethynyl-2'-deoxyuridine-positive proliferation rate (P=0.003 5). On a molecular expression scale, dimethylglycine significantly downregulated the messenger RNA expression of multiple core senescence-associated secretory phenotype inflammatory factors, including interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1. Concurrently, it effectively suppressed the protein expression of critical cell cycle arrest markers, diminishing p16 protein levels by 57.3% (P=0.000 4) and p21 protein levels by 27.2% (P=0.000 7). In the nematode Caenorhabditis elegans animal model, dimethylglycine significantly extended the mean lifespan from 20.402 d to an impressive 23.066 d (P<0.000 1) and notably enhanced overall survival rates under severe heat stress environmental conditions (P=0.017). Furthermore, systemic dimethylglycine intervention significantly mitigated age-related physiological decline by decreasing bodily lipofuscin accumulation (P<0.000 1), significantly reducing senescence-associated beta-galactosidase activity, lowering systemic reactive oxygen species fluorescence (P=0.008), and effectively alleviating overall fat accumulation (P<0.000 1). Mechanistically, extensive network pharmacology and Kyoto Encyclopedia of Genes and Genomes analyses strongly revealed that the potential targets of dimethylglycine are significantly enriched in fundamental drug metabolism and oxidative stress response pathways. Precision molecular docking simulations conclusively demonstrated that dimethylglycine forms highly stable structural interactions with the cytochrome P450 family 2 subfamily C member 9 protein, specifically highlighting the definitive formation of 5 stable hydrogen bonds involving serine 365, leucine 366, and serine 429 residues, as well as two critical salt bridge formations with arginine 97 and histidine 368 residues. It is additionally predicted to interact favorably with glutathione S-transferase family proteins. ConclusionDimethylglycine exhibits a profoundly significant and multifaceted anti-aging activity at both the cellular and entire living animal levels. By powerfully alleviating oxidative stress, heavily suppressing the core p16 and p21-dependent cellular senescence signaling pathways, and substantially mitigating the detrimental senescence-associated secretory phenotype, dimethylglycine effectively delays fundamental cellular senescence processes and drastically extends whole-organism lifespan. The biological mechanisms driving these robust protective effects are highly likely closely associated with its direct stable interactions with crucial metabolic and detoxifying enzyme systems, such as cytochrome P450 family 2 subfamily C member 9 and glutathione S-transferase family proteins, thereby systemically improving metabolic dysregulation and restoring critical redox homeostasis. This comprehensive study provides highly solid experimental evidence supporting dimethylglycine as a highly potent and safe potential anti-aging intervention agent, while simultaneously offering a clear molecular mechanistic explanation for the previously documented high abundance of dimethylglycine observed within exceptionally long-lived human populations.

Loss of protein homeostasis is a hallmark of cellular senescence, and ribosome pausing plays a crucial role in the collapse of proteostasis. However, our understanding of ribosome pausing in senescent cells remains limited. In this study, we utilized ribosome profiling and G-quadruplex RNA immunoprecipitation sequencing techniques to explore the impact of RNA G-quadruplex (rG4) on the translation efficiency in senescent cells. Our results revealed a reduction in the translation efficiency of rG4-rich genes in senescent cells and demonstrated that rG4 structures within coding sequence can impede translation both in vivo and in vitro. Moreover, we observed a significant increase in the abundance of rG4 structures in senescent cells, and the stabilization of the rG4 structures further exacerbated cellular senescence. Mechanistically, the RNA helicase DHX9 functions as a key regulator of rG4 abundance, and its reduced expression in senescent cells contributing to increased ribosome pausing. Additionally, we also observed an increased abundance of rG4, an imbalance in protein homeostasis, and reduced DHX9 expression in aged mice. In summary, our findings reveal a novel biological role for rG4 and DHX9 in the regulation of translation and proteostasis, which may have implications for delaying cellular senescence and the aging process.
G-Quadruplexes ; Cellular Senescence ; Ribosomes/genetics* ; Humans ; Animals ; Mice ; DEAD-box RNA Helicases/genetics* ; Protein Biosynthesis ; RNA/chemistry* ; Neoplasm Proteins

OBJECTIVE: To explore the protective effect of glycosaminoglycans (GAG) on vascular endothelium in patients with sepsis. METHODS: A prospective study was conducted on adult patients with sepsis admitted to the intensive care unit (ICU) of Hangzhou Normal University Affiliated Hospital from December 2022 to December 2023. Patients were randomly divided into conventional treatment group and GAG intervention group. Both groups were treated according to the 2021 Surviving Sepsis Campaign Guidelines. The GAG intervention group was additionally treated with GAG (2 mL of sulodexide intramuscular injection once daily for 7 days) on the basis of conventional treatment. Venous blood was collected from patients at 0, 6, 24, 48, 72 hours and 7 days after enrollment to detect serum vascular endothelial glycocalyx [heparan sulfate (HS) and syndecan-1 (SDC-1)], inflammatory markers [C-reactive protein (CRP), procalcitonin (PCT), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6)], and coagulation markers [prothrombin time (PT), activated partial thromboplastin time (APTT), antithrombin-III (AT-III), fibrinogen (Fib), D-Dimer], and to perform acute physiology and chronic health evaluation II (APACHE II), sequential organ failure assessment (SOFA), and International Society on Thrombosis and Haemostasis (ISTH) scores. The prognosis of patients (length of hospital stay, ICU and 28-day mortality) was observed. The receiver operator characteristic curve (ROC curve) was drawn to evaluate the value of HS in predicting the prognosis of sepsis patients, and the correlation between endothelial glycocalyx degradation products and various clinical indicators was analyzed. RESULTS: A total of 50 adult patients with sepsis meeting the inclusion criteria were enrolled, with 25 in the conventional treatment group and 25 in the GAG intervention group. In terms of degradation products of endothelial glycocalyx, compared to baseline, both groups showed an increasing trend in HS and SDC-1 levels post-treatment. However, the GAG intervention group exhibited significantly lower HS levels at 72 hours and 7 days, as well as lower SDC-1 levels at 6, 24, 48, 72 hours and 7 days compared to the conventional group. Among the surviving patients, the HS levels at 72 hours and SDC-1 levels at 6 hours of treatment in the GAG intervention group were significantly reduced compared to the conventional treatment group. In terms of severity score, compared with before treatment, the GAG intervention group showed a significant decrease in APACHE II, SOFA, and ISTH scores after 7 days of treatment. The SOFA scores of the GAG intervention group after 48 hours and 7 days of treatment were significantly lower than those of the conventional treatment group. In terms of inflammatory indicators, compared with before treatment, the GAG intervention group showed a significant decrease in IL-6 levels after 48 hours of treatment. With the prolongation of treatment time, the CRP levels of both groups of patients showed a significant downward trend, and at 7 days of treatment, the CRP level in the GAG intervention group was significantly lower than that in the conventional treatment group. In terms of coagulation function, with prolonged treatment time, PT and APTT of both groups of patients showed an increasing trend, while Fib showed a decreasing trend. The GAG intervention group showed a significant prolongation of PT after 72 hours of treatment compared to the conventional treatment group. In terms of prognosis, there were no statistically significant differences in ICU and 28-day mortality rates between the two groups. The GAG intervention group had significantly shorter hospital stays than the conventional treatment group. ROC curve analysis showed that HS, CRP, APTT, IL-6, APACHE II, SOFA, and ISTH scores were predictive factors for the prognosis of sepsis patients (all P < 0.05). Compared to a single indicator, the combined detection of multiple indicators has a higher value in predicting the prognosis of sepsis patients [area under the curve (AUC) = 0.911, 95% confidence interval (95%CI) was 0.817-1.000], with a sensitivity of 76.9% and a specificity of 91.9%. Correlation analysis showed that HS was significantly negatively correlated with Fib, PT, TNF-α, IL-6, and PCT (r values were -0.338, -0.396, -0.288, -0.319, and -0.340, all P < 0.05), while HS was significantly positively correlated with D-Dimer and CRP (r values were 0.347 and 0.354, both P < 0.05); SDC-1 was significantly negatively correlated with Fib, PT, APTT, TNF-α, IL-6, and ISTH scores (r values were -0.314, -0.294, -0.408, -0.353, -0.289, -0.287, all P < 0.05). CONCLUSIONS Early glycocalyx degradation can occur in sepsis patients. GAG have a protective effect on,the vascular endothelium, reducing the severity of sepsis and providing organ protection. HS, CRP, APTT, IL-6, APACHE II score, SOFA score, and ISTH score are independent predictive factors for the prognosis of sepsis patients. The combination of HS and the above indicators can significantly improve the accuracy of prediction.
Humans ; Sepsis/blood* ; Glycocalyx/drug effects* ; Glycosaminoglycans/pharmacology* ; Prospective Studies ; Endothelium, Vascular/metabolism* ; Syndecan-1/blood* ; Male ; Female ; C-Reactive Protein/metabolism* ; Interleukin-6/blood* ; Heparitin Sulfate/blood* ; Middle Aged ; Adult ; Tumor Necrosis Factor-alpha/blood* ; Procalcitonin/blood*

Objective To investigate the distribution of virulence genes of Klebsiella pneumoniae(KPN)and to evaluate the diagnostic efficacy of peg-344 for hypervirulent strains.Methods KPN isolates were col-lected from January to December in 2023 in Xuanwu Hospital,Capital Medical University.Whonet5.6 was used to analyze the distribution and drug resistance of bacterial strains.Toxicity testing included wire string test,PCR amplification of virulence genes(peg-344,rmpA,iutA,iroB),K1 and K2 capsule serotypes,serum resistance test,and diagnostic efficacy of detection was analyzed by using receiver operating characteristic curve.Results A total of 122 KPN isolates were collected,including 45(36.9%)sensitive strains,20(16.4%)extended-spectrum β-lactamase positive strains,and 57(46.7%)carbapenem-resistant Klebsiella pneumoniae strains.The specimens were mainly isolated from sputum,urine,and blood,and mainly came from Department of Urology,Department of Neurology,Intensive Care Unit,and Department of Neurosurgery.The positive rate of string test was 27.9%.PCR detected K1(12.3%),K2(8.2%),peg-344(62.3%),rmpA(60.7%),and iutA(73.8%),but the iroB result was negative,and strains with multiple virulence genes accounted for 63.1%.The results of the serum resistance test showed that 43.5%,31.1%,and 25.4%of the samples were at levels 1-2,3-4,and 5-6,respectively.peg-344 had the largest area under the curve for diagnosing the hy-pervirulent strains,followed by peg-344+iutA and peg-344+rmpA.Conclusion KPN is widely distributed in the hospital,and there are a variety of virulence genes.peg-344 has clinical value in distinguishing low viru-lence from high virulence in KPN.

Systemic lupus erythematosus(SLE)is a chronic autoimmune disease with complex etiology and diverse clinical manifestations.Its pathogenesis is complex,and the clinical treatment effect is not yet ide-al.Lipids are precursors of bioactive metabolites and components of cell membranes,exerting direct and indi-rect regulatory effects on signal transduction,gene regulation,and cell activation.Furthermore,lipids are one of the most significantly changing biomarkers in the serum of SLE patients.This article reviews the abnormal manifestations of lipid metabolism in SLE,the regulation of lipid metabolism and immune cell function,and possible therapeutic applications,providing new ideas for the diagnosis and treatment of SLE.

Objective:To investigate the ameliorative effects of N-acetyl-D-mannosamine(ManNAc) on glucose and lipid metabolic disorders in obese mice.Methods:In vivo experiments were conducted using 21 four-week-old C57BL/6JGpt mice, randomly divided into three groups( n=7 per group): a normal control group, a high-fat diet(HFD) control grooup, and a ManNAc treatment group(400 mg·kg -1·d -1). The intervention lasted for 20 weeks. Body weight, food intake, and fasting blood glucose levels were monitored weekly. Glucose tolerance tests(GTT), insulin sensitivity tests(ITT), and respiratory metabolism monitoring were performed in the 17th, 18th, and 19th weeks, respectively. At the end of the experiment, whole-body fat distribution was assessed, and serum lipid profiles were measured. Liver and adipose tissue weights were recorded, and histological analyses including HE staining of liver, adipose and pancreatic tissues were performed. Liver transcriptome sequencing and quantitative real-time PCR(qPCR) were conducted to evaluate hepatic gene expression. In vitro, a hepatic steatosis model was established by inducing HepG2 cell with 0.4 mmol/L oleic acid, followed by treatment with 500 μg/mL ManNAc. Lipid accumulation was assessed using BODIPY staining, and the expression of lipid metabolism-related genes was quantified by qPCR. Results:ManNAc administration attenuated HFD-induced weight gain, reduced total body fat volume, and decreased liver and adipose tissue weights as well as intracellular lipid accumulation. Pancreatic islet numbers increased, while fasting blood glucose levels, glucose tolerance, and insulin sensitivity significantly improved. Serum levels of triglycerides, total cholesterol, and low-density lipoprotein levels were decreased, accompanied by enhanced energy expenditure. Additionally, hepatic expression of Cd36, Fabp3, and Scd1 was downregulated. In vitro, ManNAc significantly reduced lipid accumulation in HepG2 cells and downregulated the expression of Cd36, Fabp3, and Scd1 genes.Conclusion:ManNAc may improve glucose and lipid metabolism by modulating the PPARs-mediated fatty acid metabolic pathway, reducing lipogenesis, promoting fatty acid oxidation and energy expenditure, and enhancing insulin sensitivity, ultimately ameliorating disorders in obese mice.

Objective:To study the feasibility of design and harvest of free medial sural artery perforator flap with the "two-point and two-line method".Methods:From September 2022 to June 2023, Suzhou Ruihua Orthopaedic Hospital implemented the "two-point and two-line method" to guide preoperative perforator positioning and flap design. Thirty medial sural artery perforator flaps were successfully harvested with the method, and 21 wounds of hand and 9 of foot and ankle were reconstructed with the flaps. The size of soft tissue defects were 2.5 cm×2.5 cm-7.0 cm×14.5 cm, and the flaps size were 3.0 cm×3.0 cm-7.5 cm×15.0 cm. All donor sites were directly closed or by skin grafting. All patients were entered in 6-15 months of postoperative outpatient follow-up, and the recovery of donor and recipient sites was assessed by the comprehensive evaluation scales. The sensory function of the flaps was evaluated using the sensory function evaluation standard of British Medical Research Council (BMRC).Results:All perforators were successfully located with 47 perforators in total, and all of them were musculocutaneous perforator. It was found that there was 1 perforator in 14 flaps, 2 perforators in 15 flaps and 3 perforators in 1 flap. All 30 flaps survived after surgery, beside 2 flaps that had arterial insufficiency but survived successfully after surgical exploration. All donor sites healed in one stage. Comprehensive evaluation scale of flap was employed to evaluate the flaps and the scores were 84 points to 96 points with an average score of 92.5 points. The excellent and good grades were achieved in 27 flaps and 3 flaps, respectively, with a combined excellent and good rate at 100%. Sensation of the flaps was evaluated by BMRC with 1 flap of S 1, 17 of S 2 and 12 of S 3. Conclusion:The "two-point and two-line method" has been used in design of the perforator flap of medial sural artery. This method is simple and accurate, and is feasible and ideal in design of flaps before surgery.

Invasive Aspergillosis (IA) is a severe filamentous fungal infection caused by opportunistic pathogenic Aspergillus. Due to its insidious incidence and high mortality rate, accurate diagnosis of IA is in urgent need. Recent advances in molecular diagnostic techniques have enabled novel approaches for Aspergillus detection in clinical fungal laboratory. To this end, this paper summarizes recent progress in molecular detection of Aspergillus nucleic acids and discusses its value in IA diagnosis. The findings provide guidance for both current diagnostic approaches and the development of new in vitro diagnostic technologies for IA.

Sepsis was redefined in 2016 by the updated Sepsis 3.0 criteria as a life-threatening organ dysfunction caused by dysregulated immune response to infection. This revision introduced the sequential organ failure assessment (SOFA) score as one of the key diagnostic criteria, making the diagnosis of sepsis more precise and clinically applicable. Despite significant advancements in the diagnosis and treatment of sepsis, its high incidence, mortality rate, and healthcare costs remain major global public health challenges. The core pathogenesis of sepsis involves severe dysregulation of the host immune response, which further leads to tissue damage and multiple organ dysfunction. Therefore, in-depth research into the immune response mechanisms of sepsis is crucial for optimizing clinical treatment strategies. This article systematically summarizes the characteristics of pathogenic microorganisms in sepsis, its pathogenesis, immune features at various stages, and the challenges faced in clinical treatment. It also explores the potential value of precision medicine in the clinical diagnosis and treatment of sepsis, aiming to provide references for addressing key issues in multidrug resistance and immune mechanism research in sepsis.

Background: s/Aims: Non-invasive models stratifying clinically significant portal hypertension (CSPH) are limited. Herein, we developed a new non-invasive model for predicting CSPH in patients with compensated cirrhosis and investigated whether carvedilol can prevent hepatic decompensation in patients with high-risk CSPH stratified using the new model. Methods: Non-invasive risk factors of CSPH were identified via systematic review and meta-analysis of studies involving patients with hepatic venous pressure gradient (HVPG). A new non-invasive model was validated for various performance aspects in three cohorts, i.e., a multicenter HVPG cohort, a follow-up cohort, and a carvediloltreating cohort. Results: In the meta-analysis with six studies (n=819), liver stiffness measurement and platelet count were identified as independent risk factors for CSPH and were used to develop the new “CSPH risk” model. In the HVPG cohort (n=151), the new model accurately predicted CSPH with cutoff values of 0 and –0.68 for ruling in and out CSPH, respectively. In the follow-up cohort (n=1,102), the cumulative incidences of decompensation events significantly differed using the cutoff values of <–0.68 (low-risk), –0.68 to 0 (medium-risk), and >0 (high-risk). In the carvediloltreated cohort, patients with high-risk CSPH treated with carvedilol (n=81) had lower rates of decompensation events than non-selective beta-blockers untreated patients with high-risk CSPH (n=613 before propensity score matching [PSM], n=162 after PSM). Conclusions Treatment with carvedilol significantly reduces the risk of hepatic decompensation in patients with high-risk CSPH stratified by the new model.