Ergopeptines or their derivatives are widely used for treating neurodegenerative and cerebrovascular diseases. The nonribosomal peptide synthetase-d-lysergyl peptide synthetase A (LPSA) determines ergopeptine formation but the detailed mechanism remains to be elucidated. Here, we characterized two LPSAs from Claviceps purpurea Cp-1 strain through heterologous expression in Aspergillus nidulans feeding with d-lysergic acid. We proved that Cp-LPSA1 catalyzed the formation of ergocornine, α-ergocryptine, and β-ergocryptine, precisely controlled by the substrate specificity of its three modules. Cp-LPSA2 was initially inactive but could be restored to catalyze α-ergosine formation. Using this platform, we validated that P1-LPSA1 and P1-LPSA2 from the reported C. purpurea P1 strain catalyzed ergotamine and α-ergocryptine formation, respectively. Typically, the non-ribosomal peptide codes implicated in every module of the LPSAs were defined and elucidated, in which certain key residues could play a switched role for substrate specificity and product interconversion. By constructing chimeric LPSAs through module assembly, the production of the desired ergopeptines was achieved. Notably, 1.46 mg/L of α-ergocryptine and 1.09 mg/L of ergotamine were produced respectively by mixed-culture of C. paspali No. 24 (fermentation supernatant) and the recombinants of A. nidulans. Our findings provide insights into the biosynthetic mechanism of ergopeptines and lay a foundation for directed ergopeptine biosynthesis.

Nigella sativa L. seeds have been traditionally utilized in Chinese folk medicine for centuries to treat vitiligo. This study revealed that the ethanolic extract of Nigella sativa L. (HZC) enhances melanogenesis and mitigates oxidative stress-induced cellular senescence and dysfunction in melanocytes. In accordance with established protocols, the ethanol fraction from Nigella sativa L. seeds was extracted, concentrated, and lyophilized to evaluate its herbal effects via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, tyrosinase activity evaluation, measurement of cellular melanin contents, scratch assays, senescence-associated β-galactosidase (SA-β-gal) staining, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis for expression profiling of experimentally relevant proteins. The results indicated that HZC significantly enhanced tyrosinase activity and melanin content while notably increasing the protein expression levels of Tyr, Mitf, and gp100 in B16F10 cells. Furthermore, HZC effectively mitigated oxidative stress-induced cellular senescence, improved melanocyte condition, and rectified various functional impairments associated with melanocyte dysfunction. These findings suggest that HZC increases melanin synthesis in melanocytes through the activation of the MAPK, PKA, and Wnt signaling pathways. In addition, HZC attenuates oxidative damage induced by H₂O₂ therapy by activating the nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway and enhancing the activity of downstream antioxidant enzymes, thus preventing premature senescence and dysfunction in melanocytes.
Oxidative Stress/drug effects* ; Melanocytes/cytology* ; Cellular Senescence/drug effects* ; Nigella sativa/chemistry* ; Plant Extracts/pharmacology* ; Seeds/chemistry* ; Mice ; Animals ; Melanins/metabolism* ; Monophenol Monooxygenase/metabolism* ; Humans

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.

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 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.

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.