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1.
J Inflamm Res ; 17: 2499-2511, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699596

RESUMO

Background: Tuberculosis (TB) is one of the most infectious diseases caused by Mycobacterium tuberculosis (M. tb), and the diagnosis of active tuberculosis (TB) and latent TB infection (LTBI) remains challenging. Methods: Gene expression files were downloaded from the GEO database to identify the differentially expressed genes (DEGs). The ssGSEA algorithm was applied to assess the immunological characteristics of patients with LTBI and TB. Weighted gene co-expression network analysis, protein-protein interaction network, and the cytoHubba plug-in of Cytoscape were used to identify the real hub genes. Finally, a diagnostic model was constructed using real hub genes and validated using a validation set. Results: Macrophages and natural killer cells were identified as important immune cells strongly associated with TB. In total, 726 mRNAs were identified as DEGs. MX1, STAT1, IFIH1, DDX58, and IRF7 were identified as real hub immune-related genes. The diagnostic model generated by the five real hub genes could distinguish active TB from healthy controls or patients with LTBI. Conclusion: Our study may provide implications for the diagnosis and drug development of M. tb infections.

2.
Gut ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38621924

RESUMO

OBJECTIVE: Targeting bacterial translocation in cirrhosis is limited to antibiotics with risk of antimicrobial resistance. This study explored the therapeutic potential of a non-absorbable, gut-restricted, engineered carbon bead adsorbent, Yaq-001 in models of cirrhosis and acute-on-chronic liver failure (ACLF) and, its safety and tolerability in a clinical trial in cirrhosis. DESIGN: Performance of Yaq-001 was evaluated in vitro. Two-rat models of cirrhosis and ACLF, (4 weeks, bile duct ligation with or without lipopolysaccharide), receiving Yaq-001 for 2 weeks; and two-mouse models of cirrhosis (6-week and 12-week carbon tetrachloride (CCl4)) receiving Yaq-001 for 6 weeks were studied. Organ and immune function, gut permeability, transcriptomics, microbiome composition and metabolomics were analysed. The effect of faecal water on gut permeability from animal models was evaluated on intestinal organoids. A multicentre, double-blind, randomised, placebo-controlled clinical trial in 28 patients with cirrhosis, administered 4 gr/day Yaq-001 for 3 months was performed. RESULTS: Yaq-001 exhibited rapid adsorption kinetics for endotoxin. In vivo, Yaq-001 reduced liver injury, progression of fibrosis, portal hypertension, renal dysfunction and mortality of ACLF animals significantly. Significant impact on severity of endotoxaemia, hyperammonaemia, liver cell death, systemic inflammation and organ transcriptomics with variable modulation of inflammation, cell death and senescence in the liver, kidneys, brain and colon was observed. Yaq-001 reduced gut permeability in the organoids and impacted positively on the microbiome composition and metabolism. Yaq-001 regulated as a device met its primary endpoint of safety and tolerability in the clinical trial. CONCLUSIONS: This study provides strong preclinical rationale and safety in patients with cirrhosis to allow clinical translation. TRIAL REGISTRATION NUMBER: NCT03202498.

3.
Phytomedicine ; 127: 155494, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38471370

RESUMO

BACKGROUND: Parkinson's disease (PD), a neurodegenerative disorder, is characterized by motor symptoms due to the progressive loss of dopaminergic neurons in the substantia nigra (SN) and striatum (STR), alongside neuroinflammation. Asiaticoside (AS), a primary active component with anti-inflammatory and neuroprotective properties, is derived from Centella asiatica. However, the precise mechanisms through which AS influences PD associated with inflammation are not yet fully understood. PURPOSE: This study aimed to explore the protective mechanism of AS in PD. METHODS: Targets associated with AS and PD were identified from the Swiss Target Prediction, Similarity Ensemble Approach, PharmMapper, and GeneCards database. A protein-protein interaction (PPI) network was constructed to identify potential therapeutic targets. Concurrently, GO and KEGG analyses were performed to predict potential signaling pathways. To validate these mechanisms, the effects of AS on 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD in mice were investigated. Furthermore, neuroinflammation and the activation of the NLRP3 inflammasome were assessed to confirm the anti-inflammatory properties of AS. In vitro experiments in BV2 cells were then performed to investigate the mechanisms of AS in PD. Moreover, CETSA, molecular docking, and molecular dynamics simulations (MDs) were performed for further validation. RESULTS: Network pharmacology analysis identified 17 potential targets affected by AS in PD. GO and KEGG analyses suggested the biological roles of these targets, demonstrating that AS interacts with 149 pathways in PD. Notably, the NOD-like receptor signaling pathway was identified as a key pathway mediating AS's effect on PD. In vivo studies demonstrated that AS alleviated motor dysfunction and reduced the loss of dopaminergic neurons in MPTP-induced PD mice. In vitro experiments demonstrated that AS substantially decreased IL-1ß release in BV2 cells, attributing this to the modulation of the NLRP3 signaling pathway. CETSA and molecular docking studies indicated that AS forms a stable complex with NLRP3. MDs suggested that ARG578 played an important role in the formation of the complex. CONCLUSION: In this study, we first predicted that the potential target and pathway of AS's effect on PD could be NLRP3 protein and NOD-like receptor signaling pathway by network pharmacology analysis. Further, we demonstrated that AS could alleviate symptoms of PD induced by MPTP through its interaction with the NLRP3 protein for the first time by in vivo and in vitro experiments. By binding to NLRP3, AS effectively inhibits the assembly and activation of the inflammasome. These findings suggest that AS is a promising inhibitor for PD driven by NLRP3 overactivation.


Assuntos
Intoxicação por MPTP , Fármacos Neuroprotetores , Doença de Parkinson , Triterpenos , Camundongos , Animais , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Intoxicação por MPTP/tratamento farmacológico , Intoxicação por MPTP/metabolismo , Neuroproteção , Doenças Neuroinflamatórias , Simulação de Acoplamento Molecular , Microglia , Doença de Parkinson/metabolismo , Neurônios Dopaminérgicos , Anti-Inflamatórios/uso terapêutico , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
4.
Nano Lett ; 24(8): 2520-2528, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38359360

RESUMO

Enzymatic catalysis presents an eco-friendly, energy-efficient method for lignin degradation. However, challenges arise due to the inherent incompatibility between enzymes and native lignin. In this work, we introduce a supramolecular catalyst composed of fluorenyl-modified amino acids and Cu2+, designed based on the aromatic stacking of the fluorenyl group, which can operate in ionic liquid environments suitable for the dissolution of native lignin. Amino acids and halide anions of ionic liquids shape the copper site's coordination sphere, showcasing remarkable catechol oxidase-mimetic activity. The catalyst exhibits thermophilic property, and maintains oxidative activity up to 75 °C, which allows the catalyzed degradation of the as-dissolved native lignin with high efficiency even without assistance of the electron mediator. In contrast, at this condition, the native copper-dependent oxidase completely lost its activity. This catalyst with superior stability and activity offer promise for sustainable lignin valorization through biocatalytic routes compatible with ionic liquid pretreatment, addressing limitations in native enzymes for industrially relevant conditions.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Lignina/química , Cobre , Oxirredutases , Catálise , Aminoácidos
5.
Nat Prod Res ; : 1-8, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389428

RESUMO

Quality markers (Q-markers) are of great significance for quality evaluation of herbal medicines. Zhenyuan Capsule (ZYC) is a kind of Chinese patent medicine used to treat cardiovascular diseases. However, reliable and effective Q-markers for ZYC are still lacking. Herein, a UHPLC-Q/Orbitrap-MS/MS was performed to characterise the preliminary chemical profile of ZYC. A total of 86 components were characterised among which 20 constituents were unambiguously identified by reference compounds. Based on network pharmacology, seven major ginsenosides with great importance in the network were identified as Q-markers among which ginsenoside Re with the highest betweenness was screened to inhibit the development of coronary heart disease (CHD) by binding with vascular endothelial growth factor A (VEGFA). Docking and molecular dynamics simulation studies suggested that ginsenoside Re stably bound to VEGFA. Quantitative determination and chemical fingerprinting analysis were performed using HPLC-DAD. The results showed that ginsenosides screened might function as potential Q-markers for ZYC.

6.
Hepatol Int ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184503

RESUMO

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. In this study, we aimed to investigate the role and regulatory mechanism of Annexin A2 (ANXA2) in the pathogenesis of NAFLD. METHODS: Histological analyses and ELISA were used to illuminate the expression of ANXA2 in NAFLD and healthy subjects. The role of ANXA2 was evaluated using high-fat diet (HFD)-fed mice via vein injection of adeno-associated viruses (AAV) knocking down ANXA2 or non-targeting control (NC) shRNAs. Moreover, HepG2 and LO2 cells were employed as in vitro hepatocyte models to investigate the expression and function of ANXA2. RESULTS: ANXA2 was confirmed to be one of three hub genes in liver injury, and its expression was positively correlated with NAFLD activity score (NAS) and macrophage infiltration in NAFLD. Moreover, ANXA2 was significantly upregulated in NAFLD patients and HFD-fed mice. LPS/TLR4 pathway strongly upregulated ANXA2 expression, which is mediated by direct ANXA2 promoter binding by TLR4 downstream NF-κB p65 and c-Jun transcription factors. Increased ANXA2 expression was correlated with decreased autophagy flux and autophagy was activated by the depletion of ANXA2 in the models of NAFLD. Furthermore, ANXA2 interference led to the activation of AMPK/mTOR signaling axis, which may play a causal role in autophagy flux and the amelioration of steatosis. CONCLUSIONS: ANXA2 is a pathological predictor and promising therapeutic target for NAFLD. ANXA2 plays a crucial role in linking inflammation to hepatic metabolic disorder and injury, mainly through the blockage of AMPK/mTOR-mediated lipophagy.

8.
Asian J Surg ; 47(1): 176-183, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37419802

RESUMO

BACKGROUND: Postoperative atrial fibrillation (POAF) is a common complication after major thoracic operations. The objective of this case-control study was to identify the risk factors for POAF following lung cancer surgery. METHODS: In total, 216 patients with lung cancer who were selected from three different hospitals were followed up between May 2020 and May 2022. They were divided into two groups: case group, patients with POAF and control group, patients without POAF (case-control). Risk factors associated with POAF were investigated using univariate and multivariate logistic regression analyses. RESULTS: Risk factors that were significantly associated with POAF were preoperative brain-type natriuretic peptide (BNP) levels [odds ratio (OR): 4.46; 95% confidence interval (CI): 1.52-13.06; P = 0.0064], sex (OR: 0.07; 95%CI: 0.02-0.28; P = 0.0001), preoperative white blood cell (WBC) count (OR: 3.00; 95%CI: 1.89-4.77; P < 0.0001), lymph node dissection (OR: 11.49; 95%CI: 2.81-47.01; P = 0.0007), and cardiovascular disease (OR: 4.93; 95%CI: 1.14-21.31; P = 0.0326). CONCLUSION: In summary, data from the three hospitals suggested that preoperative BNP levels, sex, preoperative WBC count, lymph node dissection, and hypertension/coronary heart disease/myocardial infarction were associated with a significantly high risk of POAF following lung cancer surgery.


Assuntos
Fibrilação Atrial , Cardiopatias , Neoplasias Pulmonares , Humanos , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/etiologia , Estudos de Casos e Controles , Neoplasias Pulmonares/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fatores de Risco
9.
Gerontology ; 70(2): 155-164, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38008089

RESUMO

INTRODUCTION: Pneumonia is a common and devastating complication following hip fracture surgery in older patients. Time to surgery is a potentially modifiable factor associated with improved prognosis, and we aim to quantify the time-effect relationship between time to surgery and in-hospital postoperative pneumonia (IHPOP) and identify the effect of delayed surgery on the risk of IHPOP. METHODS: We analyzed clinical data of older hip fracture patients (≥60 years) undergoing surgical treatments at a tertiary referral trauma center between 2015 and 2020. Restricted cubic spline (RCS) was used to fit the time-effect relationship between time to surgery and IHPOP. Based on the results of RCS, we divided patients into two groups of "early surgery" and "delayed surgery." A 1:1 propensity score matching (PSM) analysis and multivariate conditional logistic regression analysis were performed to minimize the selection bias and determine the association magnitude. Subgroup analysis was conducted to assess potential interaction effects between delayed surgery and common risk factors for IHPOP. RESULTS: 3,118 eligible patients were included. The RCS curve showed an inverse S-shape trend and the relative risk of IHPOP decreased in the range of days 2-3 and increased on day 1 and day 3 or more post-injury, with the lowest point on day 3. PSM yielded 1,870 matched patients and delayed surgery (>3 days) was identified to be independently associated with IHPOP (relative ratio, 1.66; 95% confidence interval, 1.12-2.46; p value, 0.011). We observed positive interaction effects between delayed surgery and age of 80 years or more, female gender, COPD, heart disease, ASA score ≥3, anemia, and hypoproteinemia. CONCLUSION: The relative risk of IHPOP decreased in the range of 2-3 days and increased on day 1 and day 3 or more post-injury. Delayed surgery (>3 days) was identified to be independently associated with a 1.66-fold increased risk of IHPOP.


Assuntos
Fraturas do Quadril , Pneumonia , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fraturas do Quadril/complicações , Fraturas do Quadril/cirurgia , Fatores de Risco , Pneumonia/etiologia , Pneumonia/complicações , Hospitais , Estudos Retrospectivos
10.
Fitoterapia ; 172: 105787, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38122855

RESUMO

Eleutherine bulbosa (Mill.) Urb. is a medicinal and edible plant with various benefits for humans and animals. In this work, four new phenolic constituents (1-4), along with six known phenolic compounds (5-10) were obtained from the red bulbs of E. bulbosa. Their structures with absolute configurations were characterized by extensive spectroscopic analysis, combined with HR-ESI-MS and quantum mechanical electronic circular dichroism (ECD). Compounds 1 and 2 are novel homologous and heterodimers, respectively, featuring an unusual spiro ring system. All isolated phenolic constituents were tested for their antibacterial effects. The results revealed four phenolic compounds 1-3 and 7 showed moderate antibacterial activity against Bacillus subtilis, Staphylococcus aureus and Escherichia coli with minimum inhibitory concentration (MIC) values ranging from 15.6 to 250.0 µg/mL.


Assuntos
Antibacterianos , Iridaceae , Animais , Humanos , Estrutura Molecular , Staphylococcus aureus , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Fenóis/química , Escherichia coli
11.
Artigo em Inglês | MEDLINE | ID: mdl-38064610

RESUMO

Objective: To assess lower extremity deep vein thrombosis (DVT) risk factors after artificial femoral head replacement for elderly femoral neck fractures. A nomogram model was constructed to predict its risk. Methods: In analyzing 144 participants who underwent artificial femoral head replacement for elderly femoral neck fractures, researchers collected clinical data to identify factors associated with lower extremity DVT. The study collected numerous variables ranging from age and sex to history of lower extremity DVT and use of anticoagulant drugs after surgery. The patients were in two groups: those who developed DVT (n = 62) and those who did not (n = 82). Multivariate logistic regression analysis helped to identify factors influencing the occurrence of DVT after artificial femoral head replacement. The software packages used were R 4.1.0 and RMS. Results: Univariate and multivariate regression analysis identified age, ASA level, D-dimer of lower limb DVT, ALB, and PLT as predictive risk factors of lower extremity DVT after artificial femoral head replacement for elderly femoral neck fractures. Those risk factors were used to construct a clinical predictive nomogram. The calibration curves for hypertension in patients with OSAHS risk revealed excellent accuracy of the predictive nomogram model. The unadjusted concordance index (C-index) for the model was 0.877 [95% confidence interval (CI), 0.805-0.942]. The AUC was 0.8375002. Decision curve analysis showed that the predictive model could be applied clinically when the threshold probability was 20 to 80%. Conclusions: The researchers constructed and validated a clinical nomogram to predict the occurrence of lower extremity DVT after artificial femoral head replacement in elderly patients with femoral neck fractures. Age, ASA level, D-dimer, and history of lower limb DVT, ALB, and PLT were demonstrated to be predictive risk factors of lower extremity DVT in this circumstance. This practical prognostic nomogram may help improve clinical decision-making.

12.
Nano Lett ; 23(24): 11461-11468, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38079506

RESUMO

Challenges persist in replicating enzyme-like active sites with functional group arrangements in supramolecular catalysis. In this study, we present a supramolecular material comprising Fmoc-modified histidine and copper. We also investigated the impact of noncanonical amino acids (δmH and εmH), isomers of histidine, on the catalytic process. The Fmoc-δmH-based nanoassembly exhibits an approximately 15-fold increase in oxidative activity and an ∼50-fold increase in hydrolytic activity compared to Fmoc-εmH (kcat/Km). This distinction arises from differences in basicity and ligation properties between the ε- and δ-nitrogen of histidine. The addition of guanosine monophosphate further enhances the oxidative activity of the histidine- and methylated histidine-based catalysts. The Fmoc-δmH/Cu2+-based nanoassembly catalyzes the oxidation/hydrolysis cascade of 2',7'-dichlorofluorescein diacetate, benefiting from the synergistic effect between the copper center and the nonligating ε-nitrogen of histidine. These findings advance the biomimetic catalyst design and provide insights into the mechanistic role of essential residues in natural systems.


Assuntos
Biomimética , Histidina , Catálise , Cobre , Histidina/química , Hidrólise , Nitrogênio , Estresse Oxidativo
13.
ACS Appl Mater Interfaces ; 15(42): 48945-48951, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37823579

RESUMO

We have engineered a colorimetric sensor capable of selective and sensitive detection of amino acids. This sensor employs a supramolecular copper-dependent oxidase mimic as the probe, stemming from our prior research. The oxidase mimic is constructed through the self-assembly of commercially available guanosine monophosphate (GMP), Fmoc-lysine, and Cu2+. It catalyzes the formation of a red product with a maximum absorbance at 510 nm. The changes in color and absorbance are responsive to both the concentrations and types of amino acids present. This effect is most pronounced in the presence of histidine, with a detection limit (LOD) of 6.4 nM. Furthermore, the catalytic probe can distinguish histidine from histamine and imidazole propionate, as well as 1-methyl-histidine from 3-methyl-histidine, based on their distinct coordination capacities with copper. This underscores the high selectivity of the sensing platform. Both theoretical simulations and experimental results (including UV-vis spectra, fluorescence, and EPR) indicate that the amino acids may engage in copper center coordination, thereby impeding O2 access to copper─a pivotal aspect of the oxidase catalysis. This sensing platform, characteristic of its swift response, simple fabrication, and exceptional sensitivity and selectivity, can also be applied to detect other biological analytes such as nucleotides. It holds potential for use in environmental and biochemical analyses.


Assuntos
Colorimetria , Cobre , Colorimetria/métodos , Cobre/química , Histidina/química , Catálise , Oxirredutases
14.
BMJ Open ; 13(10): e065990, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37813532

RESUMO

INTRODUCTION: Post-tuberculosis lung damage (PTLD) refers to the residual pulmonary impairment following the completion of antituberculosis (TB) therapy, characterised by persistent respiratory symptoms and abnormal pulmonary function. The risk factors and biomarkers for PTLD have been scarcely investigated. More importantly, whether and to what extent cigarette smoking is involved in PTLD remain to be known. METHODS AND ANALYSIS: This prospective observational study will enrol 400 male smoking or non-smoking patients aged 25-65 years, with newly confirmed active TB between 2022 and 2024, from the Department of Respiratory and Critical Care Medicine at Peking University Third Hospital and the Tuberculosis Department at Beijing Geriatric Hospital. Because females rarely smoke in China, we will enrol only males in this study. Demographic data, smoking history and amount, clinical symptoms, lung function, and chest CT findings will be prospectively collected. Respiratory questionnaires, lung function measurements and chest CT examinations will be performed immediately after, and 1 year, 2 years and 3 years after the completion of TB treatment. Peripheral blood samples will be obtained at baseline and at the end of anti-TB therapy, and a Luminex xMAP-based multiplex immunoassay will be used to measure inflammatory mediators and cytokines in serum. The collected data will be analysed to determine the incidence and factors/biomarkers of PTLD according to smoking status. ETHICS AND DISSEMINATION: The study was approved by the Ethics Committee of Peking University Third Hospital (approval number: (2022)271-03; approval date: 8 June 2022). The research results will be disseminated through scientific and medical conferences and will be published in an academic journal. TRIAL REGISTRATION NUMBER: NCT04966052.


Assuntos
Fumantes , Tuberculose , Idoso , Humanos , Masculino , População do Leste Asiático , Pulmão/diagnóstico por imagem , não Fumantes , Estudos Observacionais como Assunto , Fatores de Risco , Tuberculose/complicações , Tuberculose/tratamento farmacológico , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Adulto , Pessoa de Meia-Idade
15.
ACS Appl Bio Mater ; 6(10): 3984-4001, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37707491

RESUMO

In the field of carbon nanomaterials, carbon dots (CDs) have become a preferable choice in biomedical applications. Based on the concept of green chemistry, CDs derived from traditional Chinese medicines (TCMs) have attracted extensive attention, including TCM charcoal drugs, TCM extracts, and TCM small molecules. The design and preparation of CDs from TCMs (TCMs-CDs) can improve the inherent characteristics of TCMs, such as solubility, particle size distribution, and so on. Compared with other precursor materials, TCMs-CDs have outstanding intrinsic bioactivities and potential pharmacological effects. However, the research of TCMs-CDs in biomedicine is not comprehensive, and their mechanisms have not been understood deeply either. In this review, we will provide concise insights into the recent development of TCMs-CDs, with a major focus on their preparation, formation, precursors, and bioactivities. Then we will discuss the perfect transformation from TCMs to TCMs-CDs. Finally, we discuss the opportunities and challenges for the application of TCMs-CDs in clinical treatment.

16.
J Mater Chem B ; 11(30): 7117-7125, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37409588

RESUMO

The de novo design of artificial biocatalysts with enzyme-like active sites and catalytic functions has long been an attractive yet challenging goal. In this study, we present a nucleotide-Cu2+ complex, synthesized through a one-pot approach, capable of catalyzing ortho-hydroxylation reactions resembling those of minimalist monooxygenases. Both experimental and theoretical findings demonstrate that the catalyst, in which Cu2+ coordinates with both the nucleobase and phosphate moieties, forms a ternary-complex intermediate with H2O2 and tyramine substrates through multiple weak interactions. The subsequent electron transfer and hydrogen (or proton) transfer steps lead to the ortho-hydroxylation of tyramine, where the single copper center exhibits a similar function to natural dicopper sites. Moreover, Cu2+ bound to nucleotides or oligonucleotides exhibits thermophilic catalytic properties within the temperature range of 25 °C to 75 °C, while native enzymes are fully deactivated above 35 °C. This study may provide insights for the future design of oxidase-mimetic catalysts and serve as a guide for the design of primitive metallocentre-dependent enzymes.


Assuntos
Cobre , Oxigenases de Função Mista , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Cobre/química , Oxirredução , Nucleotídeos/metabolismo , Peróxido de Hidrogênio , Tiramina
17.
Molecules ; 28(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513328

RESUMO

Four new meroterpenoids, Clavilactone M-P, possessing novel aminoglycoside moiety (1-4) and a 10-membered carbocycle fused with an α,ß-epoxy-γ-lactone, were isolated from Clitocybe clavipes, a basidiomycete. Their structures with absolute configurations were determined by extensive analysis of their spectroscopic data, and the ECD method. All the isolated compounds (1-4) were evaluated for their antitumor activity against three human cancer cell lines using the MTT assay. Compound 1 and 2 exhibited a significant suppression of cell viability in the Hela (IC50 = 22.8 and 19.7 µM) cell line.


Assuntos
Antineoplásicos , Basidiomycota , Humanos , Aminoglicosídeos/farmacologia , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Basidiomycota/química , Linhagem Celular Tumoral , Antibacterianos
18.
Molecules ; 28(13)2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446862

RESUMO

Traditional Chinese medicine has been proven to be of great significance in cardioprotective effects. Clinopodium chinense (Lamiaceae) has unique advantages in the treatment and prevention of cardiovascular diseases. Tournefolic acid B (TAB) was proven to be a potent component against myocardial ischemia reperfusion injury (MIRI) from Clinopodium chinense (Lamiaceae). This article will attempt to establish a gram-scale synthesis method of TAB and discuss the structure-activity relationship of its analogs. The total synthesis of TAB was completed in 10 steps with an overall yield of 13%. In addition, analogs were synthesized, and their cardioprotective activity was evaluated on the hypoxia/reoxygenation of H9c2 cells. Amidation of the acid position is helpful to the activity, while methylation of phenolic hydroxyl groups greatly decreased the cardioprotective activity. The easily prepared azxepin analogs also showed cardioprotective activity. Most of the clogP values calculated by Molinspiration ranged from 2.5 to 5, which is in accordance with Lipinski's rule of 5. These findings represent a novel kind of cardioprotective agent that is worthy of further study.


Assuntos
Compostos Heterocíclicos com 3 Anéis , Traumatismo por Reperfusão Miocárdica , Humanos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Cardiotônicos/farmacologia , Relação Estrutura-Atividade , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos , Apoptose
19.
Nat Commun ; 14(1): 4040, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37419896

RESUMO

Enzymes fold into unique three-dimensional structures to distribute their reactive amino acid residues, but environmental changes can disrupt their essential folding and lead to irreversible activity loss. The de novo synthesis of enzyme-like active sites is challenging due to the difficulty of replicating the spatial arrangement of functional groups. Here, we present a supramolecular mimetic enzyme formed by self-assembling nucleotides with fluorenylmethyloxycarbonyl (Fmoc)-modified amino acids and copper. This catalyst exhibits catalytic functions akin those of copper cluster-dependent oxidases, and catalytic performance surpasses to date-reported artificial complexes. Our experimental and theoretical results reveal the crucial role of periodic arrangement of amino acid components, enabled by fluorenyl stacking, in forming oxidase-mimetic copper clusters. Nucleotides provide coordination atoms that enhance copper activity by facilitating the formation of a copper-peroxide intermediate. The catalyst shows thermophilic behavior, remaining active up to 95 °C in an aqueous environment. These findings may aid the design of advanced biomimetic catalysts and offer insights into primordial redox enzymes.


Assuntos
Cobre , Metaloproteínas , Cobre/química , Biomimética , Oxirredutases , Aminoácidos , Nucleotídeos
20.
Colloids Surf B Biointerfaces ; 228: 113392, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37290198

RESUMO

Herein, a nonreversible heat-induced supramolecular gel based on natural products was reported for the first time. This natural triterpenoid, fupenzic acid (FA), isolated from the roots of Rosa laevigata, was discovered to be capable of forming supramolecular gel spontaneously in 50 % ethanol-water solution induced by heating. Distinguished from the common thermosensitive gels, the FA-gel showed a distinctive nonreversible phase transition from the liquid to gel state upon heating. In this work, the entire gelation process of FA-gel induced by heating was recorded digitally by microrheology monitor. And a unique heat-induced gelation mechanism based on self-assembled FA has been proposed by using various experimental methods and molecular dynamics (MD) simulation. Its excellent injectability and stability were also demonstrated. Furthermore, the FA-gel had been evaluated to exhibit better anti-tumor activity and higher biosafety comparing with its equivalent free-drug, which opened up a new possibility to reinforce antitumor efficacy by using natural product gelator originated from traditional Chinese medicine (TCM) without any complicated chemical modifications.


Assuntos
Temperatura Alta , Géis/química , Transição de Fase
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