In recent years, polysaccharides have received much attention because of their high safety and good immunological activity. The study of polysaccharide in vivo process is a key scientific problem that needs to be solved for polysaccharide drug development. Some progress has been made in the field of polysaccharide pharmacokinetics and immunomodulation. However, due to the lack of both chromogenic and light-absorbing groups and the complex molecular structure of polysaccharides, the in vivo processes and immunomodulatory mechanisms of polysaccharides have been slow to be investigated. The effective combination of multiple techniques can break the bottleneck of difficult tracing and unknown immunomodulatory mechanism of polysaccharides in vivo, and promote the development and utilization of polysaccharides. In this paper, we systematically summarize the key techniques in the study of polysaccharide in vivo processes and immunomodulatory mechanisms in order to provide technical references and research ideas for the study of polysaccharide in vivo processes and immunomodulatory mechanisms.

Objective To explore the roles of iron overload in pro-atherogenic activation of foam cells.Methods RAW264.7 and MOVAS cells were stimulated by oxLDL,ferrimine citrate and deferoxamine respectively.Prussian Blue and Oil Red O staining were used to detect iron deposition and foam cell.CCK-8 test,DHE probe,ELISA,RT-qPCR were performed to detect the cell death rate,reactive oxygen species(ROS)generation,lipid peroxidation molecules[glutathione peroxidase(GSH),glutathione peroxidase 4(GPX4),malondialdehyde(MDA)content]and the mRNA level of ATP binding cassette transporter A1(ABCA1),ATP binding cassette transporter G1(ABCG1),inductible nitris oxide synthase(iNOS),arginase-1(Arg-1),α-smooth muscle actin(α-SMA),smooth muscle 22 alpha(SM22a),osteopontin(OPN),Interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α).Results Iron overload could reduced reverse cholesterol transporters(ABCA1 and ABCG1),promote foam cells generation,increased cell death rate,induced the expression of lipid peroxidation molecules(GSH,GPX4,MDA),and promoted pro-inflammatory M1 marker of macrophage and synthetic marker expression of vascular smooth muscle cell(VSMC)and inflammatory cytokines(IL-1β,TNF-α).Conclusion Iron overload promotes the generation of foam cells derived from macrophages and smooth muscle cells and transform them into pro-atherosclerotic phenotype,aggravates cell lipid peroxidation and inflammatory reaction,which contributes to the progress of atherosclerosis.

Natural products are important sources of drug discovery. However, the traditional methods of extraction and isolation, as well as chemical synthesis for obtaining natural products are associated with issues such as operational complexity, high costs, low efficiency, and environmental pollution. Constructing microbial cell factories through synthetic biology methods to produce medicinal natural products has the advantages of high efficiency, low cost, and environmental protection. Nevertheless, the scope and yield improvement of the products are limited by the limitations of enzymes in microbial cell factories. Protein engineering is considered one of the most effective approaches to overcome these limitations. This article introduces commonly used methods of protein engineering technology and summarizes its specific applications in improving enzyme performance, modifying the enzymatic environment, and promoting the development of synthetic biology tools in the field of pharmaceutical natural product synthesis. Furthermore, it analyzes the current bottlenecks and challenges in protein engineering and looks forward to its future application prospects, offering insights for the development and practical use of protein engineering technology.

Aim To investigate the protective poten-tial of paeoniflorin 6-oxy-benzenesulfonate(CP-25)in preserving knee cartilage integrity in osteoarthritis mice through inhibition of GRK2 activity.Methods The posttraumatic osteoarthritis model was established fol-lowing DMM surgery.The experiment consisted of a sham operation group,a model group,a CP-25 admin-istration group,and a paroxetine positive control group.Intragastric administration commenced after the surgery.After 12 weeks of administration,the animals were euthanized.Micro-CT imaging was used to ob-serve the knee cartilage degeneration and abnormal bone remodeling,and the joint histopathology of mice was observed by staining with ferrubens solid green.Immunohistochemistry and immunofluorescence were used to detect the expression level of related molecules in cartilage tissue.Furthermore,Western blot was em-ployed to determine GRK2 and EP4 membrane protein expression levels as well as total protein levels of GRK2 and MMP13 following CP-25 treatment.Results Compared with the sham operation group,the articular cartilage in the model group was significantly degrad-ed,with the cartilage surface calcifying and osteo-phytes forming.CP-25 could significantly reduce the number of osteophytes and the thickness of the sub-chondral plate of articular cartilage,promote the regen-eration of the cartilage matrix,reduce the expression of cartilage matrix degradation protein,and have a signifi-cant protective effect on knee cartilage.Immunohisto-chemical and immunofluorescence results showed that compared with the model group,CP-25 treatment sig-nificantly decreased the expressions of GRK2,AD-AMTS5 and MMP13 in knee tissue and increased the expressions of Col Ⅱ and Aggrecan in knee tissue.The results of in vitro experiments showed that CP-25 ad-ministration could significantly reduce the expression levels of GRK2 membrane protein and total protein,in-crease the level of EP4 membrane protein,and de-crease the level of MMP13.Conclusions The ad-ministration of CP-25 can significantly promote the re-generation of articular cartilage matrix in OA mice,re-duce the degradation of cartilage matrix,and exhibit therapeutic effects on OA.The mechanism behind this is related to the inhibition of GRK2-mediated cartilage matrix metabolism.

Aim To investigate the mechanisms of Ke-chuanting granules(KCT)inhibiting the IL-33/ILC2s pathway and pathogenic T cells to intervene in allergic airway inflammation.Methods Network pharmacolo-gy was utilized to analyze the potential targets and mechanisms of KCT-treated asthma.Allergic asthma models were induced in mice using OVA.Lung histo-pathology was conducted to observe injury changes.ELISA and quantitative PCR were utilized to measure key inflammatory factors and their mRNA expression levels in Th2-type asthma.Western blot was used to detect the phosphorylation levels of relevant proteins in the MAPK pathway.Flow cytometry was performed to evaluate the proportions of ILC2s,Th1,Th 17,Th2 and Treg cells.Results Network pharmacology iden-tified 227 main active components and 143 key targets of KCT in treating asthma,primarily enriched in signa-ling pathways such as MAPK and IL-17.Further vali-dation experiments demonstrated that KCT significantly alleviated lung inflammatory injury in asthmatic mice,reduced the number of B cells,production of I L-4,TNF-α and TGF-β,downregulated JNK phosphoryla-tion levels in lung tissue,as well as mRNA levels of Il-33,Bcl11b,Rorα,Tcf-7,Jun,Mapk3 and Mapk14.KCT intervention reduced the numbers of ILC2s and Th 17 cells in lungs and spleens of mice,and inhibited Th2 cell infiltration in lungs.Conclusions KCT ex-hibits therapeutic effects on allergic airway inflamma-tion in asthma,closely associated with the inhibition of the IL-33/ILC2s pathway,pathogenic T cell subsets,and JNK-MAPK signaling pathway.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To investigate the clinical phenotypes and genotypes of children with congenital fibrinogen disorder(CFD).Methods A retrospective analysis was conducted on the clinical data of 16 children with CFD.Polymerase chain reaction was used to amplify all exons and flanking sequences of the FGA,FGB,and FGG genes,and sequencing was performed to analyze mutation characteristics.Results Among the 16 children,there were 9 boys(56%)and 7 girls(44%),with a median age of 4 years at the time of attending the hospital.Among these children,9(56%)attended the hospital due to bleeding events,and 7(44%)were diagnosed based on preoperative examination.The children with bleeding events had a significantly lower fibrinogen activity than those without bleeding events(P<0.05).Genetic testing was conducted on 12 children and revealed a total of 12 mutations,among which there were 4 novel mutations,i.e.,c.80T>C and c.1368delC in the FGA gene and c.1007T>A and C.1053C>A in the FGG gene.There were 2 cases of congenital afibrinogenemia caused by null mutations of the FGA gene,with relatively severe bleeding symptoms.There were 7 cases of congenital dysfibrinogenemia mainly caused by heterozygous missense mutations of the FGG and FGA genes,and their clinical phenotypes ranged from asymptomatic phenotype to varying degrees of bleeding.Conclusions The clinical phenotypes of children with CFD are heterogeneous,and the severity of bleeding is associated with the level of fibrinogen activity,but there is a weak association between clinical phenotype and genotype.

AIM To study the lignans and terpenoids from Alangium chinense(Lour.)Harms subsp.pauciflorum Fang.METHODS The 70%ethanol extract was isolated and purified by various column chromatography,then the structures of obtained compounds were identified by physicochemical properties and spectral data.RESULTS Twenty-four compounds were isolated and identified and identified as(+)-pinoresinol)(1),medioresinol(2),syringaresinol(3),dehydrodiconifery alcohol-9′-β-D-glucopyranoside(4),7,9,9′-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-4-O-β-D-glucopyranoside(5),citrusin B(6),dihydrodehydrodiconiferyl alcohol-4-O-β-D-glucopyranosides(7),5-methoxy-(+)-isolariciresinol(8),rel-(7R,8S)-3,3′,5-trimethoxy-4′,7-epoxy-8,5′-neolignan-4,9,9′-triol-9-β-D-glucopyranoside(9),(+)-lyoniresinol-3α-O-β-D-glucopyranoside(10),longifloroside B(11),(7S,8R)-1-[4-O-(β-D-glucopyranosyl)-3-methoxyphenyl]-2-[4-(3-hydroxypropyl)-2,6-dimethoxyphenoxy]-1,3-propanediol(12),(7R,8S)-4,9,9′-trihydroxyl-3-methoxyl-7,8-dihydrobenzofuran-1′-propylneolignan-3′-O-β-D-glucopyranoside(13),(7S,8R)-4,9,9′-trihydroxy-3,3′,5-trimethoxy-8,4′-oxy-neolignan-4-O-β-D-glucopyranoside(14),cedrusin-4-O-β-D-glucopyranoside(15),2,6,2′,6′-tetramethoxy-4,4′-bis(2,3-epoxy-1-hydroxypropyl)biphenyl(16),3-oxo-11α,12α-epoxy-olean-28,13β-olide(17),mansonone E(18),mansonone G(19),mansonone H(20),roseoside(21),bullatantriol(22),3-O-α-L-arabinopyranosyl-28-O-β-D-glucopyranosyl pomolic acid(23),Hederagenin(24).CONCLUSION Compounds 1-16 are lignans,and 17-24 are terpenoids.Compounds 3-9,11-17,22-24 are isolated from Alangium genus for the first time;compounds 1,2,10,18-21 are first isolated from this plant.

The pathogenesis of the nephrotic syndrome is complex and the pathological types are diverse, so the minor symptoms in its early phases are difficult to detect. Renal biopsy is the gold indicator for the diagnosis of renal pathology and progression, but poor patient compliance shows, and the optimal treatment time is often delayed. Therefore, the discovery of biomarkers for early diagnosis and disease progression monitoring is of great clinical significance. In this study, doxorubicin-injured podocyte models were used to simulate human kidney disease at different stages of progression. LC-MS-based metabolomic technology combined with statistical methods was used to screen and identify the potential biomarkers associated with early injury or progression of podocytes. The results of cell viability, apoptosis tests and podocyte structural protein analysis showed that the model was successfully constructed, and the degree of podocyte injury was significantly different between the two modeling methods. According to VIP > 1 and P < 0.05 based on the orthogonal partial least squares discriminant analysis (OPLS-DA) model, nine differential metabolites reflecting early podocyte injury and twelve differential metabolites reflecting the injury progression were screened, respectively. ROC analysis was adopted to focus on the potential biomarkers that can reflecting the early podocyte injury including L-tryptophan, guanosine triphosphate (GTP), 5′-thymidylic acid (dTMP) and thymidine, and the biomarkers reflecting the injury progression of podocytes composed of L-phenylalanine, L-tyrosine acid, uridine 5′-diphosphate (UDP) and guanosine 5′-diphosphate (GDP) AUC > 0.85. It indicated that these eight metabolites may have high sensitivity and diagnostic ability. This study provides a reference for the research on biomarkers of progressive diseases.

The secondary metabolites of plants are important sources of natural drugs. Betula plants have abundant pharmacological value, complex mechanism and wide applications, which are closely related to the triterpenoids of theirs. Triterpenoids in Betula species are mainly divided into dammarane-type, ocotillol-type, oleanane-type, lupane-type and cycloaltunane-type. The extracts of Betula species have varieties of activities such as anti-tumor, anti-inflammatory, anti-oxidant, anti-bacterial, etc. And the biosynthetic pathways of triterpenoids after 2,3-oxidosqualene are split into four branches of dammarenediol-II, lupeol, cycloartenol and amyrin according to the different oxidosqualene cyclases. This review summarizes the chemical constituents, pharmacological activities and biosynthetic pathways of triterpenoids in Betula plants. It provides a reference for the research and development of new drugs and the production of these triterpenoids in microbial cell factories by synthetic biology methods.