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1.
ACS Omega ; 9(20): 22450-22458, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38799354

RESUMEN

Four new cytochalasans, marchaetoglobins A-D (1-4), along with five known compounds (5-9), were isolated from the marine-sponge-associated fungus Chaetomium globosum 162105. Compounds 1-4 represent examples of 19,20-seco-chaetoglobosins, of which compound 1 is the first furan-containing cytochalasan. Their structures and absolute configurations were elucidated by extensive spectroscopic analyses and electronic circular dichroism calculations. Compounds 5, 8, and 9 displayed weak to moderate antibacterial activities against Bacillus thuringiensis, Edwardsiella piscicida, Vibrio alginolyticus, and Pseudomonas syringae pv. actinidiae with minimum inhibitory concentration values ranging from 5 to 25 µg/mL. In addition, compounds 2, 3, and 5 showed potent in vivo proangiogenic activity in transgenic zebrafish, comparable to the positive control.

2.
Chem Biodivers ; : e202400832, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712949

RESUMEN

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity. Among them, compounds 3-8 displayed antibacterial effects against Staphylococcus epidermidis, Bacillus thuringiensis, Pseudomonas syringae pv. Actinidiae, Vibrio alginolyticus, and Edwardsiella piscicida with minimum inhibitory concentration (MIC) values ranging from 10 to 25 µg/mL.

3.
J Nat Prod ; 87(5): 1376-1383, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38662398

RESUMEN

A precursor-directed biosynthesis approach led to the accumulation of seven new neoantimycin derivatives (1-7) from Streptomyces conglobatus RJ2. Structure elucidation was conducted using NMR and HRESIMS analysis, and the absolute configuration was determined by advanced Marfey's method, Mosher's analysis, and ECD analysis. The obtained compounds revealed selective and significant cytotoxicity, specifically against colorectal cancer cells bearing the K-ras mutation, with IC50 values ranging from 40 nM to 3.5 µM.


Asunto(s)
Streptomyces , Streptomyces/química , Streptomyces/metabolismo , Humanos , Estructura Molecular , Antineoplásicos/farmacología , Antineoplásicos/química , Ensayos de Selección de Medicamentos Antitumorales , Mutación , Resonancia Magnética Nuclear Biomolecular , Compuestos Orgánicos
4.
Mar Drugs ; 22(4)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38667765

RESUMEN

Marine natural products are important sources of novel drugs. In this study, we isolated 4-hydroxyphenylacetic acid (HPA) from the marine-derived fungus Emericellopsis maritima Y39-2. The antithrombotic activity and mechanism of HPA were reported for the first time. Using a zebrafish model, we found that HPA had a strong antithrombotic activity because it can significantly increase cardiac erythrocytes, blood flow velocity, and heart rate, reduce caudal thrombus, and reverse the inflammatory response caused by Arachidonic Acid (AA). Further transcriptome analysis and qRT-PCR validation demonstrated that HPA may regulate autophagy by inhibiting the PI3K/AKT/mTOR signaling pathway to exert antithrombotic effects.


Asunto(s)
Autofagia , Fibrinolíticos , Fenilacetatos , Pez Cebra , Animales , Fenilacetatos/farmacología , Autofagia/efectos de los fármacos , Fibrinolíticos/farmacología , Transducción de Señal/efectos de los fármacos , Productos Biológicos/farmacología , Trombosis/tratamiento farmacológico , Modelos Animales de Enfermedad , Organismos Acuáticos
5.
Mar Drugs ; 22(3)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38535441

RESUMEN

Inflammatory bowel disease (IBD) is a chronic inflammatory bowel disease with unknown pathogenesis which has been gradually considered a public health challenge worldwide. Peptides derived from Rapana venosa have been shown to have an anti-inflammatory effect. In this study, peptide LLTRAGL derived from Rapana venosa was prepared by a solid phase synthesis technique. The protective effects of LLTRAGL were studied in a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced zebrafish colitis model. The underlying mechanisms of LLTRAGL were predicted and validated by transcriptome, real-time quantitative PCR assays and molecular docking. The results showed that LLTRAGL reduced the number of macrophages migrating to the intestine, enhanced the frequency and rate of intestinal peristalsis and improved intestinal inflammatory damage. Furthermore, transcriptome analysis indicated the key pathways (NOD-like receptor signal pathway and necroptosis pathway) that link the underlying protective effects of LLTRAGL's molecular mechanisms. In addition, the related genes in these pathways exhibited different expressions after TNBS treatment. Finally, molecular docking techniques further verified the RNA-sequencing results. In summary, LLTRAGL exerted protective effects in the model of TNBS-induced colitis zebrafish. Our findings provide valuable information for the future application of LLTRAGL in IBD.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Perciformes , Caracoles , Animales , Pez Cebra , Simulación del Acoplamiento Molecular , Péptidos
6.
Public Health ; 230: 66-72, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38507918

RESUMEN

OBJECTIVES: Heart failure (HF) is on the rise as a global health problem, but information on its burden in Asia is limited. This study aimed to assess the burden, trends, and underlying causes of HF in the Asian region. STUDY DESIGN AND METHODS: Data on HF in Asia from 1990 to 2019, including prevalence, years lived with disability (YLD), and underlying causes, were extracted from the Global Burden of Diseases 2019. The cases, the age-standardized prevalence, and the YLD were compared between the age groups, the sexes, the sociodemographic index, and the locations. The proportion of age-standardized prevalence rates of HF attributable to 16 underlying causes was also analyzed. RESULTS: In 2019, the age-standardized prevalence rate of HF per 100,000 persons in Asia was 722.45 (95% uncertainty interval [UI]: 591.97-891.64), with an estimated 31.89 million cases (95% UI: 25.94-39.25). From 1990 to 2019, the prevalence of age-standardized HF in Asia decreased by 4.51%, reflecting the global trend (-7.06%). Age-standardized YLD rates of HF exhibited patterns similar to prevalence rates. Among Asian countries, China had the highest age-standardized prevalence rate, followed by Kuwait and Jordan. Hypertensive heart disease was the leading cause of HF, followed by ischemic heart disease and rheumatic heart disease. CONCLUSIONS: Although the burden of HF in Asia showed a gradual decline between 1990 and 2019, it remains a significant health challenge that requires increased attention. Regional disparities in HF burden are evident, emphasizing the need for urgent prevention and control measures at the regional and national levels.


Asunto(s)
Personas con Discapacidad , Insuficiencia Cardíaca , Humanos , Carga Global de Enfermedades , Asia/epidemiología , Prevalencia , Salud Global , Insuficiencia Cardíaca/epidemiología , Años de Vida Ajustados por Calidad de Vida , Incidencia
7.
Eur J Clin Pharmacol ; 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502358

RESUMEN

BACKGROUND: The pharmacokinetics of tacrolimus (TAC) show high intra-patient variability (IPV), which is associated with poor long-term outcomes following adult liver transplantation (LT). However, this relationship remains to be confirmed in pediatric liver transplant (PLT) recipients. The present study aimed to investigate the association between TAC IPV and grafts or patient outcomes after pediatric liver transplantion. METHODS: This retrospective study included 848 PLT recipients (including infants) between January, 2016, and June, 2021. The IPV of TAC concentrations was estimated by calculating the coefficient of variation (CV) of trough concentrations in whole blood within 1 month after transplantation. Patients were categorized into two groups, low IPV (CV < 45%) and high IPV (CV ≥ 45%), based on the third quartile of the CV distribution. RESULTS: A total of 848 patients were included in our study. The low CV group included 614 patients, with a mean TAC trough concentration of 8.59 ± 1.65 ng/ml and a median CV of 32.37%. In contrast, the high CV group included 214 patients, the mean TAC trough concentration and median CV were 8.81 ± 2.00 ng/ml and 54.88%, respectively. The median hospital duration was significantly higher in the high CV group (22 days vs. 20 days, P = 0.01). Univariate analysis was performed to evaluate the significant differences in 1-year recipient survival (P = 0.041) and 1-year graft survival (P = 0.005) between the high- and low-CV groups. Moreover, high CV (HR 2.316, 95%CI 1.026-5.231, P = 0.043) and persistent EBV viremia (HR 13.165, 95%CI 3.090-56.081, P < 0.001) were identified as independent risk factors for 1- year mortality after PLT. CONCLUSIONS: PLT recipients with high TAC trough concentration of CV in the first month were associated with poor 1-year outcomes. This CV calculation provides a valuable strategy to monitor TAC exposure.

8.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515152

RESUMEN

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Asunto(s)
Vías Biosintéticas , Sintasas Poliquetidas , Pirrolidinonas , Sintasas Poliquetidas/metabolismo , Bacterias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Péptido Sintasas/genética
9.
J Nat Prod ; 87(2): 396-403, 2024 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-38330072

RESUMEN

Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A-F (1-6), were isolated from the marine sponge Dysidea arenaria collected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B-D (2-4) possess two rare secomeroterpene scaffolds. Arenarialins A-F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.


Asunto(s)
Dysidea , Poríferos , Sesquiterpenos , Animales , Dysidea/química , Poríferos/química , Sesquiterpenos/farmacología , Sesquiterpenos/química , Antiinflamatorios/farmacología , FN-kappa B , Estructura Molecular
10.
Phytochemistry ; 220: 114017, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342290

RESUMEN

Marine sponges are well known as prolific producers of structurally diverse molecules with valuable pharmacological potential. As part of our ongoing program to discover bioactive compounds from marine sponges collected from the Xisha Islands in the South China Sea, a chemical study on the specimens of Hippospongia lachne was conducted. As a result, eight undescribed compounds, including four zwitterionic alkylpyridinium salts, hippospondines A-D (1-4), and four 3-alkylpyridine alkaloids, hippospondines E (5), F (6), and (±)-hippospondine G (7), were isolated from the marine sponge H. lachne, together with one known 3-alkylpyridine alkaloid (8). The undescribed structures were elucidated by HRESIMS, NMR, DP4+ and CP3 probability analysis, and the Snatzke's method. Hippospondines A-D (1-4) represent the rare example of inner salt type alkylpyridinium alkaloid with a farnesyl moiety. Compounds 1-3 and 8 were subjected to cytotoxic and lymphocyte proliferation assays. Compound 3 exhibited a weak promotion effect on the ConA-induced T lymphocyte proliferation.


Asunto(s)
Alcaloides , Antineoplásicos , Poríferos , Animales , Espectroscopía de Resonancia Magnética , Antineoplásicos/química , Alcaloides/química , China , Estructura Molecular
11.
Int Immunopharmacol ; 129: 111576, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38350353

RESUMEN

Cyanogramide (AC14), a novel alkaloid, isolated from the fermentation broth of the marine-derived Actinoalloteichus cyanogriseus. However, the exact role of AC14 in inflammatory bowel disease (IBD) is poorly understood. Our results demonstrated that AC14 exhibited significant inhibition of IL-6 release in THP-1 cells and a "Caco-2/THP-1" coculture system after stimulation with LPS for 24 h. However, no significant effect on TNF-α production was observed. Furthermore, in 2.5 % DSS-induced colitis mice, AC14 treatment led to improvement in body weight, colon length, and intestine mucosal barrier integrity. AC14 also suppressed serum IL-6 production and modulated dysregulated microbiota in the mice. Mechanistically, AC14 was found to inhibit the phosphorylation of Janus kinase (JAK) 2 and signal transducers and activators of transcription (STAT) 3, while simultaneously elevating the expression of suppressor of cytokine signaling (SOCS) 3, both in vivo and in vitro. These findings suggest that AC14 exerts its suppressive effects on IL-6 production in DSS-induced IBD mice through the JAK2-STAT3-SOCS3 signaling pathway. Our study highlights the potential of AC14 as a therapeutic agent for the treatment of IBD.


Asunto(s)
Alcaloides , Antineoplásicos , Enfermedades Inflamatorias del Intestino , Poríferos , Humanos , Ratones , Animales , Interleucina-6/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/genética , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Células CACO-2 , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Janus Quinasa 2/metabolismo , Poríferos/metabolismo , Alcaloides/uso terapéutico , Factor de Transcripción STAT3/metabolismo
12.
Nucleic Acids Res ; 52(7): 3886-3895, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38324471

RESUMEN

The eukaryotic epigenetic modifications 5-methyldeoxycytosine (5mC) and N6-methyldeoxyadenine (6mA) have indispensable regulatory roles in gene expression and embryonic development. We recently identified an atypical bifunctional dioxygenase CcTet from Coprinopsis cinerea that works on both 5mC and 6mA demethylation. The nonconserved residues Gly331 and Asp337 of CcTet facilitate 6mA accommodation, while D337F unexpectedly abolishes 5mC oxidation activity without interfering 6mA demethylation, indicating a prominent distinct but unclear 5mC oxidation mechanism to the conventional Tet enzymes. Here, we assessed the molecular mechanism of CcTet in catalyzing 5mC oxidation by representing the crystal structure of CcTet-5mC-dsDNA complex. We identified the distinct mechanism by which CcTet recognizes 5mC-dsDNA compared to 6mA-dsDNA substrate. Moreover, Asp337 was found to have a central role in compensating for the loss of a critical 5mC-stablizing H-bond observed in conventional Tet enzymes, and stabilizes 5mC and subsequent intermediates through an H-bond with the N4 atom of the substrates. These findings improve our understanding of Tet enzyme functions in the dsDNA 5mC and 6mA demethylation pathways, and provide useful information for future discovery of small molecular probes targeting Tet enzymes in DNA active demethylation processes.


Asunto(s)
Agaricales , Dioxigenasas , 5-Metilcitosina/metabolismo , Cristalografía por Rayos X , Dioxigenasas/química , Dioxigenasas/genética , Dioxigenasas/metabolismo , Desmetilación del ADN , Metilación de ADN , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Enlace de Hidrógeno , Modelos Moleculares , Oxidación-Reducción , Especificidad por Sustrato , Adenosina/análogos & derivados , Agaricales/enzimología
13.
Acta Pharm Sin B ; 14(1): 207-222, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38261825

RESUMEN

Modulating Tankyrases (TNKS), interactions with USP25 to promote TNKS degradation, rather than inhibiting their enzymatic activities, is emerging as an alternative/specific approach to inhibit the Wnt/ß-catenin pathway. Here, we identified UAT-B, a novel neoantimycin analog isolated from Streptomyces conglobatus, as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction (PPI) to overcome multi-drug resistance in colorectal cancer (CRC). The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels, triggering cell apoptosis through modulation of the Wnt/ß-catenin pathway. Importantly, UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels, as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts, as well as APCmin/+ spontaneous CRC models. Collectively, these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment, and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.

14.
Food Sci Nutr ; 12(1): 450-458, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38268908

RESUMEN

Calendula officinalis flowers, associated with diverse biological effects, could be utilized as functional food ingredients to play a crucial role in human health. In this study, we examined the anti-PD activity of C. officinalis flower extracts and investigated their bioactive compounds and molecular mechanisms based on LC-MS/MS assay, bioinformatic exploration and in vitro treatment of SH-SY5Y cells. C. officinalis extracts exhibited significant positive effects on the length and fluorescence density of the dopaminergic neuron region in zebrafish larvae. At 10 µg/mL, the extract restored the length to 96.54% and fluorescence density to 87.77% of the control values, which was equivalent to the effect of a positive drug, indicating the extract's powerful potential to alleviate PD symptoms. Five active compounds, including chlorogenic acid, 3,4-dicaffeoylquinic acid (DA), rutin, isorhamnetin 3-O-glucoside (IG) and calenduloside E (CE) were identified in extracts by LC-QTOF-MS/MS. Hsp90α, PI3K and ERK were revealed as core targets of DA, IG and CE in relation to anti-PD activity. The compounds docked deeply within the pocket region of Hsp90α protein, and their binding energies (∆G b) were -6.93 kcal/mol (DA), -6.51 kcal/mol (IG) and -3.03 kcal/mol (CE), respectively. Subsequently, they concurrently activated the PI3K/Akt signaling pathway and inhibited the ERK signaling pathway, thereby preventing neuronal death and alleviating neuronal degeneration. These compounds from C. officinalis could be potent nutraceutical agents with protective properties that may shield dopaminergic neurons against the damage caused by PD. Our findings provide a basis for utilizing the C. officinalis flowers in functional foods.

15.
Int J Clin Pharm ; 46(1): 90-100, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37817027

RESUMEN

BACKGROUND: Various genetic and nongenetic variables influence the high on-treatment platelet reactivity (HTPR) in patients taking clopidogrel. AIM: This study aimed to develop a novel machine learning (ML) model to predict HTPR in Chinese patients after percutaneous coronary intervention (PCI). METHOD: This cohort study collected information on 507 patients taking clopidogrel. Data were randomly divided into a training set (90%) and a testing set (10%). Nine candidate Machine learning (ML) models and multiple logistic regression (LR) analysis were developed on the training set. Their performance was assessed according to the area under the receiver operating characteristic curve, precision, recall, F1 score, and accuracy on the test set. Model interpretations were generated using importance scores by transforming model variables into scaled features and representing in radar plots. Finally, we established a prediction platform for the prediction of HTPR. RESULTS: A total of 461 patients (HTPR rate: 19.52%) were enrolled in building the prediction model for HTPR. The XGBoost model had an optimized performance, with an AUC of 0.82, a precision of 0.80, a recall of 0.44, an F1 score of 0.57, and an accuracy of 0.87, which was superior to those of LR. Furthermore, the XGBoost method identified 7 main predictive variables. To facilitate the application of the model, we established an XGBoost prediction platform consisting of 7 variables and all variables for the HTPR prediction. CONCLUSION: A ML-based approach, such as XGBoost, showed optimum performance and might help predict HTPR on clopidogrel after PCI and guide clinical decision-making. Further validated studies will strengthen this finding.


Asunto(s)
Clopidogrel , Pueblos del Este de Asia , Intervención Coronaria Percutánea , Humanos , Clopidogrel/farmacología , Estudios de Cohortes , Inhibidores de Agregación Plaquetaria/farmacología , Aprendizaje Automático
16.
Biotechnol Adv ; 70: 108295, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38052345

RESUMEN

Rare actinomycetes are highly valued as potential sources of novel bioactive secondary metabolites. Among these rare actinomycetes, the genus Saccharothrix is particularly noteworthy due to its ability to produce a diverse range of bioactive secondary metabolites. With the continuous sequencing of bacterial genomes and the rapid development of bioinformatics technologies, our knowledge of the secondary metabolic potential of Saccharothrix can become more comprehensive, but this space has not been reviewed or explored. This review presents a detailed overview of the chemical structures and bioactivities of 138 Saccharothrix-derived secondary metabolites, which are classified into five distinct groups based on their biosynthetic pathways. Furthermore, we delve into experimentally characterized biosynthetic pathways of nine bioactive metabolites. By utilizing a combination of cheminformatic and bioinformatic approaches, we attempted to establish connections between the metabolite families and the biosynthetic gene cluster families encoded by Saccharothrix strains. Our analysis provides a comprehensive perspective on the secondary metabolites that can be linked to corresponding BGCs and highlights the underexplored biosynthetic potential of Saccharothrix. This review also provides guidance for the targeted discovery and biosynthesis of novel natural products from Saccharothrix.


Asunto(s)
Actinobacteria , Actinobacteria/genética , Actinobacteria/metabolismo , Biología Computacional , Metabolismo Secundario/genética , Familia de Multigenes
17.
Angew Chem Int Ed Engl ; 63(7): e202313900, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38158383

RESUMEN

N1 -methyladenosine (m1 A) is a prevalent post-transcriptional RNA modification, and the distribution and dynamics of the modification play key epitranscriptomic roles in cell development. At present, the human AlkB Fe(II)/α-ketoglutarate-dependent dioxygenase family member ALKBH3 is the only known mRNA m1 A demethylase, but its catalytic mechanism remains unclear. Here, we present the structures of ALKBH3-oligo crosslinked complexes obtained with the assistance of a synthetic antibody crystallization chaperone. Structural and biochemical results showed that ALKBH3 utilized two ß-hairpins (ß4-loop-ß5 and ß'-loop-ß'') and the α2 helix to facilitate single-stranded substrate binding. Moreover, a bubble-like region around Asp194 and a key residue inside the active pocket (Thr133) enabled specific recognition and demethylation of m1 A- and 3-methylcytidine (m3 C)-modified substrates. Mutation of Thr133 to the corresponding residue in the AlkB Fe(II)/α-ketoglutarate-dependent dioxygenase family members FTO or ALKBH5 converted ALKBH3 substrate selectivity from m1 A to N6 -methyladenosine (m6 A), as did Asp194 deletion. Our findings provide a molecular basis for understanding the mechanisms of substrate recognition and m1 A demethylation by ALKBH3. This study is expected to aid structure-guided design of chemical probes for further functional studies and therapeutic applications.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , ARN , Humanos , ARN/química , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , ARN Mensajero/metabolismo , Desmetilación , Compuestos Ferrosos , Dioxigenasa Dependiente de Alfa-Cetoglutarato, Homólogo 3 de AlkB/metabolismo
18.
J Interv Cardiol ; 2023: 4717271, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38028026

RESUMEN

Background: Venous thromboembolism (VTE) is a common cardiovascular disease that seriously threatens human lives. Anticoagulant therapy is considered to be the cornerstone of VTE treatment. An increasing number of studies has been updated in the VTE anticoagulation field. However, no bibliometric analyses have assessed these publications comprehensively. Therefore, our study aimed to analyze the global status, hotspots, and trends of anticoagulant therapy for VTE. Methods: The relevant literature on VTE anticoagulation published between 2012 and 2021 was retrieved and collected from the Web of Science Core Collection database. VOSviewer, Cooccurrence Matrix Builder, gCLUTO, and some online visualization tools were adopted for bibliometric analysis. Results: A total of 15,152 related articles were retrieved. In recent years, the research output of VTE anticoagulation gradually increased. The United States was the most productive country. International cooperation is concentrated in North America and Europe; the most influential documents, journals, authors, and organizations were also from these two continents. Research hotspots mainly focus on clinical guidelines, VTE in special populations, non-vitamin K oral anticoagulants (NOACs), and parenteral anticoagulation. The research frontiers and trends include the assessment of NOACs and the antithrombotic management of VTE complicated with coronavirus disease 2019 (COVID-19). Conclusion: This bibliometric analysis provides a systematic overview of the VTE anticoagulation research, which will facilitate researchers to better understand the situation of VTE anticoagulation. Future studies should be dedicated to NOACs application and VTE-combined COVID-19 patients.


Asunto(s)
COVID-19 , Tromboembolia Venosa , Humanos , Administración Oral , Anticoagulantes/uso terapéutico , COVID-19/complicaciones , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/prevención & control , Tromboembolia Venosa/etiología , Vitamina K/uso terapéutico , Bibliometría
19.
Angew Chem Int Ed Engl ; 62(46): e202313109, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37779101

RESUMEN

The short-chain dehydrogenase/reductase (SDR) superfamily members acyl-ACP reductases FabG and FabI are indispensable core enzymatic modules and catalytic orientation controllers in type-II fatty acid biosynthesis. Herein, we report their distinct substrate allosteric recognition and enantioselective reduction mechanisms. FabG achieves allosteric regulation of ACP and NADPH through ACP binding across two adjacent FabG monomers, while FabI follows an irreversible compulsory order of substrate binding in that NADH binding must precede that of ACP on a discrete FabI monomer. Moreover, FabG and FabI utilize a backdoor residue Phe187 or a "rheostat" α8 helix for acyl chain length selection, and their corresponding triad residues Ser142 or Tyr145 recognize the keto- or enoyl-acyl substrates, respectively, facilitating initiation of nucleophilic attack by NAD(P)H. The other two triad residues (Tyr and Lys) mediate subsequent proton transfer and (R)-3-hydroxyacyl- or saturated acyl-ACP production.


Asunto(s)
Ácidos Grasos , Oxidorreductasas , Oxidorreductasas/metabolismo , Catálisis
20.
Trials ; 24(1): 623, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37779187

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia that requires anticoagulation therapy to prevent stroke. However, there is still a significant under-/over-treatment in stroke prevention for patients with AF. The adherence and the risk of bleeding associated with oral anticoagulation therapy (OACs) are major concerns. Shared decision-making (SDM) is an approach that involves patients and healthcare providers in making decisions about treatment options. This study aims to assess the effectiveness of a novel SDM tool for anticoagulation management in AF. METHODS: The study will be a prospective, cluster randomized controlled trial involving 440 patients with AF in 8 community health service centers (clusters) in Shanghai, China. The SDM group will receive anticoagulation management through the novel SDM tool, while the control group will receive standard care. The follow-up period will be at least 2 years. The primary outcome will be any bleeding event, while secondary outcomes include the accordance of stroke prophylaxis for AF according to the current guidelines, time in therapeutic range (TTR), the occurrences of major bleeding and thrombosis events, and patient knowledge, adherence, and satisfaction. DISCUSSION: This study will provide evidence of the effectiveness of shared decision-making in improving the appropriateness of OAC use in Chinese AF patients. The findings may inform the development of guidelines and policies for the management of AF and anticoagulation therapy in China and other countries. TRIAL REGISTRATION: ChiCTR ChiCTR2200062123. Registered on 23 July 2022.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Anticoagulantes/efectos adversos , Estudios Prospectivos , China , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/complicaciones , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto
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