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2.
Eur J Obstet Gynecol Reprod Biol ; 296: 327-332, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38520955

RESUMO

OBJECTIVE: To validate the accuracy of four early warning scores for early identification of women at risk. METHODS: This was a retrospective study of pregnant women admitted in obstetrics Critical Care Unit (ICU). Capacity of the Modified Obstetric Early Warning Score (MOEWS), ICNARC Obstetric Early Warning Score (OEWS), Maternal Early Obstetric Warning System (MEOWS chart), and Maternal Early Warning Trigger (MEWT) were compared in predicting severe maternal morbidity. Area under receiver operator characteristic (AUROC) curve was used to evaluate the predictive performance of scoring system. RESULTS: A total of 352 pregnant women were enrolled and 290 were identified with severe maternal morbidity. MOEWS was more sensitive than MEOWS chart, ICNARC OEWS and MEWT (96.9 % vs. 83.4 %, 66.6 % and 44.8 %). MEWT had the highest specificity (98.4 %), followed by MOEWS (83.9 %), ICNARC OEWS (75.8 %) and MEOWS chart (48.4 %). AUROC of MOEWS, ICNARC OEWS, MEOWS chart, and MEWT for prediction of maternal mortality were 0.91 (95 % CI: 0.874-0.945), 0.765(95 % CI: 0.71-0.82), 0.657(95 % CI: 0.577-0.738), and 0.716 (95 % CI, 0.659-0.773) respectively. MOEWS had the highest AUCs in the discrimination of serious complications in hypertensive disorders, cardiovascular disease, obstetric hemorrhage and infection. For individual vital signs, maximum diastolic blood pressure (DBP), maximum systolic blood pressure (SBP), maximum respiratory rate (RR) and peripheral oxygen saturation (SPO2) demonstrated greater predictive ability. CONCLUSION: MOEWS is more accurate than ICNARC OEWS, MEOWS chart, and MEWT in predicting the deterioration of women. The prediction ability of DBP, SBP, RR and SPO2 are more reliable.


Assuntos
Obstetrícia , Complicações na Gravidez , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Estado Terminal , Complicações na Gravidez/diagnóstico , Pressão Sanguínea
3.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257372

RESUMO

Fungi are important resource for the discovery of novel bioactive natural products. This study investigated the metabolites produced by Mariana-Trench-associated fungus Aspergillus sp. SY2601 in EY liquid and rice solid media, resulting in the isolation and structure determination of 28 metabolites, including five new compounds, asperindopiperazines A-C (1-3), 5-methoxy-8,9-dihydroxy-8,9-deoxyaspyrone (21), and 12S-aspertetranone D (26). Structures of the new compounds were elucidated based on extensive NMR spectral analyses, HRESIMS data, optical rotation, ECD, and 13C NMR calculations. The new compound 12S-aspertetranone D (26) exhibited antibacterial activity against both methicillin-resistant Staphylococcus aureus and Escherichia coli with MIC values of 3.75 and 5 µg/mL, respectively.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Sesquiterpenos , Aspergillus , Fungos , Antibacterianos/farmacologia , Escherichia coli
4.
J Pharm Anal ; 13(2): 187-200, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36908857

RESUMO

Epidemiological and animal studies indicate that pre-existing diabetes increases the risk of Parkinson's disease (PD). However, the mechanisms underlying this association remain unclear. In the present study, we found that high glucose (HG) levels in the cerebrospinal fluid (CSF) of diabetic rats might enhance the effect of a subthreshold dose of the neurotoxin 6-hydroxydopamine (6-OHDA) on the development of motor disorders, and the damage to the nigrostriatal dopaminergic neuronal pathway. In vitro, HG promoted the 6-OHDA-induced apoptosis in PC12 cells differentiated to neurons with nerve growth factor (NGF) (NGF-PC12). Metabolomics showed that HG promoted hyperglycolysis in neurons and impaired tricarboxylic acid cycle (TCA cycle) activity, which was closely related to abnormal mitochondrial fusion, thus resulting in mitochondrial loss. Interestingly, HG-induced upregulation of pyruvate kinase M2 (PKM2) combined with 6-OHDA exposure not only mediated glycolysis but also promoted abnormal mitochondrial fusion by upregulating the expression of MFN2 in NGF-PC12 cells. In addition, we found that PKM2 knockdown rescued the abnormal mitochondrial fusion and cell apoptosis induced by HG+6-OHDA. Furthermore, we found that shikonin (SK), an inhibitor of PKM2, restored the mitochondrial number, promoted TCA cycle activity, reversed hyperglycolysis, enhanced the tolerance of cultured neurons to 6-OHDA, and reduced the risk of PD in diabetic rats. Overall, our results indicate that diabetes promotes hyperglycolysis and abnormal mitochondrial fusion in neurons through the upregulation of PKM2, leading to an increase in the vulnerability of dopaminergic neurons to 6-OHDA. Thus, the inhibition of PKM2 and restoration of mitochondrial metabolic homeostasis/pathways may prevent the occurrence and development of diabetic PD.

5.
Nat Prod Res ; 37(3): 478-483, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34558370

RESUMO

A new naphthyridine analogue, named streptonaphthyridine A (1), together with eight previously reported compounds (2-9), were isolated from a Mariana Trench sediment-associated actinomycete Streptomyces sp. SY2111. Planar structure of streptonaphthyridine A was established by analyses of its HRESIMS data and extensive NMR spectra and its absolute configuration was determined by a combination of single crystal X-ray diffraction analysis and optical rotation calculations. Streptonaphthyridine A (1) had antiproliferative activity against human glioma U87MG and U251 cells with IC50 values of 7.9 ± 1.3 and 13.4 ± 2.7 µM, respectively, and the known compound monomethylsulochrin (7) showed more potent activity with IC50 values of 0.6 ± 0.1 µM for U87MG cells and 0.1 ± 0.0 µM for U251 cells.


Assuntos
Actinobacteria , Glioma , Streptomyces , Humanos , Streptomyces/química , Espectroscopia de Ressonância Magnética , Naftiridinas , Estrutura Molecular
6.
BMC Pregnancy Childbirth ; 22(1): 901, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36464694

RESUMO

BACKGROUND: Maternal mortality is still a major challenge for health systems, while severe maternal complications are the primary causes of maternal death. Our study aimed to determine whether severe maternal morbidity is effectively predicted by a newly proposed Modified Obstetric Early Warning Score (MOEWS) in the setting of an obstetric intensive care unit (ICU). METHODS: A retrospective study of pregnant women admitted in the ICU from August 2019 to August 2020 was conducted. MOEWS was calculated 24 h before and 24 h after admission in the ICU, and the highest score was taken as the final value. For women directly admitted from the emergency department, the worst value before admission was collected. The aggregate performance of MOEWS in predicting critical illness in pregnant women was evaluated and finally compared with that of the Acute Physiology and Chronic Health Evaluation II (APACHE II) score. RESULTS: A total of 352 pregnant women were enrolled; 290 women (82.4%) with severe maternal morbidity were identified and two of them died (0.6%). The MOEWSs of women with serious obstetric complications were significantly higher than those of women without serious obstetric complications [8(6, 10) vs. 4(2, 4.25), z = -10.347, P < 0.001]. MOEWSs of 24 h after ICU admission had higher sensitivity, specificity and AUROC than MOEWSs of 24 h before ICU admission. When combining the two MOEWSs, sensitivity of MOEWS was 99.3% (95% CI: 98-100), specificity 75.8% (95% CI: 63-86), positive predictive value (PPV) 95.1% (95% CI: 92-97) and negative predictive value (NPV) 95.9% (95% CI: 86-100). The areas under the receiver operator characteristic (ROC) curves of MOEWS were 0.92 (95% CI: 0.88-0.96) and 0.70 (95% CI: 0.63-0.76) of the APACHE II score. CONCLUSION: The newly proposed MOEWS has an excellent ability to identify critically ill women early and is more effective than APACHE II. It will be a valuable tool for discriminating severe maternal morbidity and ultimately improve maternal health.


Assuntos
Escore de Alerta Precoce , Morte Materna , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Unidades de Terapia Intensiva , Hospitalização
7.
Antibiotics (Basel) ; 11(11)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36358111

RESUMO

Marine-derived Streptomyces actinomycetes are one of the most important sources for the discovery of novel bioactive natural products. This study characterized the isolation, structural elucidation and biological activity evaluation of thirty compounds, including twelve previously undescribed compounds, namely hygrocins K-U (5-13, 17 and 18) and streptophenylpropanamide A (23), from the marine-associated actinomycete Streptomyces sp. ZZ1956. Structures of the isolated compounds were determined by a combination of extensive NMR spectroscopic analyses, HRESIMS data, the Mosher's method, ECD calculations, single crystal X-ray diffraction and comparison with reported data. Hygrocins C (1), D (2), F (4), N (8), Q (11) and R (12), 2-acetamide-6-hydroxy-7-methyl-1,4-naphthoquinone (22), echoside C (27), echoside A (28) and 11,11'-O-dimethylelaiophylin (30) had antiproliferative activity (IC50: 0.16-19.39 µM) against both human glioma U87MG and U251 cells with hygrocin C as the strongest active compound (IC50: 0.16 and 0.35 µM, respectively). The analysis of the structure-activity relationship indicated that a small change in the structures of the naphthalenic ansamycins had significant influence on their antiglioma activities. Hygrocins N (8), O (9), R (12), T (17) and U (18), 2-amino-6-hydroxy-7-methyl-1,4-naphthoquinone (21), 2-acetamide-6-hydroxy-7-methyl-1,4-naphthoquinone (22), 3'-methoxy(1,1',4',1″-terphenyl)-2',6'-diol (26), echoside C (27) and echoside A (28) showed antibacterial activity against methicillin-resistant Staphylococcus aureus and Escherichia coli with MIC values of 3-48 µg/mL.

8.
Molecules ; 27(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36296693

RESUMO

Marine-derived Penicillium fungi are one of the most important sources for the discovery of new bioactive natural products. This study characterized the isolation, structures, and antiglioma activities of twelve compounds, including three novel ones-penipyridinone B (1), 11S-(-)-penilloid A (2), and 11R,14E-(+)-penilloid A (3)-from the marine fungus Penicillium sp. ZZ1750. The structures of the novel compounds were determined via extensive nuclear magnetic resonance (NMR) spectroscopic analyses, high-resolution electrospray ionization mass spectroscopy (HRESIMS) data, Mosher's method, optical rotation (OR) calculations, and electronic circular dichroism (ECD) calculations. Penipyridinone B represents the first example of its structural type and showed potent antiglioma activity, with IC50 values of 2.45 µM for U87MG cells and 11.40 µM for U251 cells. The known compounds of questiomycin A (9) and xanthocillin X (10) also showed antiproliferative activity against both U87MG and U251 cells, with IC50 values of 13.65 µM to 22.56 µM. The antiglioma activity of questiomycin A and xanthocillin X may be related to the promotion of reactive oxygen species (ROS) production, the reduction of mitochondrial membrane potential (MMP), and the enhancement of caspase-3 enzyme activity.


Assuntos
Produtos Biológicos , Penicillium , Penicillium/química , Produtos Biológicos/farmacologia , Espécies Reativas de Oxigênio , Caspase 3 , Estrutura Molecular
9.
Phytochemistry ; 201: 113292, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35780923

RESUMO

Marine-derived actinomycetes from the genus Streptomycete have a huge potential for the production of metabolites with structural and bioactive uniqueness and diversity. This study described the isolation and structural elucidation of twenty metabolites, including seven previously unreported compounds galbonolide H, galbonolide I, streptophenylpropionic acid A, treptophenylpropyl ester A, streptophenvaleramide A, seco-geldanamycin A and streptorapamycin A, from the marine-associated Streptomycete sp. ZZ1944. Structures of the isolated compounds were elucidated by a combination of extensive NMR spectroscopic analyses, HRESIMS data, optical rotation and ECD calculations. The structure of galbonolide H was also confirmed by a single crystal X-ray diffraction. Both autolytimycin and seco-geldanamycin A showed potent activity against the proliferation of glioma, lung cancer, colorectal cancer and breast cancer cells. Autolytimycin blocked cell cycle of glioma cells and seco-geldanamycin A induced apoptosis of glioma cells.


Assuntos
Antineoplásicos , Glioma , Streptomyces , Antineoplásicos/farmacologia , Cristalografia por Raios X , Glioma/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Streptomyces/química
10.
Nat Prod Res ; 36(1): 460-465, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34967248

RESUMO

New talaromydien A (1) and talaroisocoumarin A (2), together with nine known compounds (3 - 11), were isolated from a culture of the marine-derived Talaromyces sp. ZZ1616 in potato dextrose broth medium. Structures of the new compounds were elucidated based on their HRESIMS data, NMR spectroscopic analyses, the modified Mosher's method, ECD, 13C NMR and optical rotation calculations. Talaroisocoumarin A showed antimicrobial activities with MIC values of 36.0 µg/mL against methicillin-resistant Staphylococcus aureus, 32.0 µg/mL against Escherichia coli, and 26.0 µg/mL against Candida albicans.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Talaromyces , Antibacterianos/farmacologia , Candida albicans , Escherichia coli , Testes de Sensibilidade Microbiana , Estrutura Molecular
11.
ACS Omega ; 6(40): 26545-26555, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34661009

RESUMO

Drug development has a high failure rate, with safety properties constituting a considerable challenge. To reduce risk, in silico tools, including various machine learning methods, have been applied for toxicity prediction. However, these approaches often confront a serious problem: the training data sets are usually biased (imbalanced positive and negative samples), which would result in model training difficulty and unsatisfactory prediction accuracy. Multitask networks obtained significantly better predictive accuracies than single-task methods, and capsule neural networks showed excellent performance in sparse data sets in previous studies. In this study, we developed a new multitask framework based on a capsule neural network (multitask CapsNet) to measure 12 different toxic effects simultaneously. We found that multitask CapsNet excelled in toxicity prediction and outperformed many other computational approaches using the multitask strategy. Only after training on biased data sets did multitask CapsNet achieve significantly improved prediction accuracy on the Tox21 Data Challenge, which gave the largest ratio of highest accuracy (8/12) among compared models. Our model gave a prediction accuracy of 96.6% for the target NR.PPAR.gamma, whose ratio of negative to positive samples was up to 36:1. These results suggested that multitask CapsNet could overcome the bias problems and would provide a novel, accurate, and efficient approach for predicting the toxicities of compounds.

12.
Bioorg Med Chem Lett ; 39: 127915, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33691166

RESUMO

A total of 106 marine microbial metabolites were evaluated for their antiproliferative activity against human lung cancer cells. Results showed that 23 compounds exhibited activity in inhibiting the proliferation of A549 and H157 cells with IC50 values ranging from 1.5 to 48.2 µM. Pyrrospirone F, chrysophanol, physcion, and purpuride G are the four most active compounds with IC50 values of 1.5-7.3 µM. Further investigation of purpuride G (a newly discovered sesquiterpene lactone) demonstrated its potent antiproliferative activity against six different lung cancer cells of A549, H157, H460, H1299, H1703, and PC9 with IC50 values of 2.1-3.3 µM. The antiproliferative activity of purpuride G against cancer cells is related to block cell cycle, induce apoptosis through regulating the apoptotic proteins Bcl-2 and Bax, and inhibit glycolysis by downregulating two key glycolytic enzymes of hexokinase 2 and pyruvate kinase M2.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
13.
Mar Drugs ; 19(2)2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33572615

RESUMO

In 2019, streptoglutarimide H (SGH) was characterized as a new glutarimide from the secondary metabolites produced by a marine-derived actinomycete Streptomyces sp. ZZ741 and shown to have in vitro antiglioma activity. However, the antiproliferative activity and potential mechanism of SGH against lung cancer cells have not yet been characterized. This study demonstrated that SGH significantly inhibited the proliferation of different lung cancer cells. In terms of mechanism of action, SGH downregulated cell cycle- and nucleotide synthesis-related proteins to block cell cycle at G0/G1 phase, reduced the expression levels of glycolytic metabolic enzymes to inhibit glycolysis, and downregulated the important cancer transcription factor c-Myc and the therapeutic target deubiquitinase USP28. Potent anticancer activity and multiple mechanisms indicated SGH to be a novel antitumor compound against lung cancer cells.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Streptomyces/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Ubiquitina Tiolesterase/antagonistas & inibidores
14.
Phytomedicine ; 80: 153383, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33091855

RESUMO

BACKGROUND: Caffeic acid 3,4-dihydroxyphenethyl ester (CADPE) is a natural polyphenolic ester isolated as a minor component from a water extract of the Chinese medicine Zhongjiefeng [Sarcandra glabra (Thunb.) Nakai (Chloranthaceae)] and has previously shown to have activity against solid tumors through the modulation of multiple targets or signal pathways. However, the activity and potential mechanism of CADPE against leukemia cells have not yet been characterized. PURPOSE: To investigate whether and how CADPE kills leukemia cells. METHOD: (1) The activity of CADPE inhibiting the growth of different leukemia cell lines was evaluated by MTT assay; (2) Cell cycle arrest and apoptosis induced by CADPE were determined by flow cytometry with FlowJo software for quantification; (3) The protein levels were analyzed by Western blot and ubiquitin-binding c-Myc was acquired by co-immunoprecipitation. RESULTS: CADPE exerted potent activity against different leukemia cell lines with low toxicity in normal cells. In terms of mechanism of action, CADPE promoted ubiquitin-proteasome-dependent degradation of c-Myc through activating glycogen synthase kinase-3ß (GSK3ß) and downregulating deubiquitinating enzyme USP28 to trigger the interaction of c-Myc with ubiquitin ligase Fbw7, resulting in the downregulation of cell cycle regulators and anti-apoptotic proteins and consequently, cell cycle arrest and cell apoptosis. CONCLUSION: CADPE is a novel c-Myc inhibitor with high activity and a unique mechanism for killing leukemia cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ácidos Cafeicos/farmacologia , Leucemia/tratamento farmacológico , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas F-Box/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Leucemia/metabolismo , Leucemia/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ubiquitina/metabolismo , Ubiquitina Tiolesterase/metabolismo
15.
Comb Chem High Throughput Screen ; 24(10): 1727-1735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33172373

RESUMO

BACKGROUND: Hepatoma is a common malignancy in the world with high morbidity and mortality. The treatment of hepatoma is limited by its poor response to many chemotherapeutic agents. Although paclitaxel (PTX) is widely used in clinical chemotherapy, the low sensitivity to hepatoma restricts its application. Combination therapy is a promising approach to resolve this dilemma. OBJECTIVE: To evaluate the interaction between paclitaxel, bufalin (BFL) and cinobufagin (CBF), and explore the optimum combination efficiently. METHODS: HepG2 cells were treated with PTX, BFL and CBF individually or in combination. Their interactions were evaluated by two classical models (Chou-Talalay model and Bliss independence). Response surface methodology (RSM) was used to explore the optimum combination. Furthermore, the optimum drug combination was verified by the morphological experiment. RESULTS: Synergistic effects were observed when cells were exposed to binary mixtures of PTX+CBF and BFL+CBF. Although the interaction of PTX and BFL was summative, a strong synergistic effect was observed when cells were exposed to ternary mixtures of PTX+BFL+CBF. The interaction results of RSM were consistent with classical models, but more efficient. Moreover, the optimum combination dose was given by RSM without the combinatorial explosion of exhaustive testing. CONCLUSION: The combination of BFL and CBF synergistically enhanced the potency of PTX against HepG2 cells. RSM could give an accurate evaluation for drug interactions and efficient prediction of optimum combination.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bufanolídeos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Paclitaxel/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Bufanolídeos/química , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Conformação Molecular , Paclitaxel/química , Propriedades de Superfície , Células Tumorais Cultivadas
16.
Cell Death Dis ; 11(11): 982, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33191401

RESUMO

Residual disease is the major cause for colorectal cancer (CRC) relapse. Herein, we explore whether and how a natural molecule CADPE killed heterogenic populations in a panel of CRC cell lines with KRAS/BRAF mutations that are natively resistant to EGFR- or VEGFR-targeted therapy, without sparing persistent cells, a reservoir of the disease relapse. Results showed that CADPE killed the tumor bulk and residual cells in the panel of CRC cell lines, rapidly inactivated c-Myc, STAT3, and NF-κB, and then decreased the protein levels of key signaling molecules for CRC, such as ß-catenin, Notch1, and the nodes of mTOR pathways; eukaryotic translation initiation factors (eIF4F); anti-apoptotic proteins (Bcl-xl, Mcl-1, and survivin); and stemness-supporting molecules (CD133, Bim-1, and VEGF). In terms of mechanism of action, concurrent downregulation of Mcl-1, Bcl-xl, and survivin was necessary for CADPE to kill CRC bulk cells, while additional depletion of CD133 and VEGF proteins was required for killing the residual CRC cells. Moreover, the disabled c-Myc, STAT3, NF-κB, and eIF4F were associated with the broadly decreased levels of anti-apoptosis proteins and pro-stemness proteins. Consistently, CADPE suppressed CRC tumor growth associated with robust apoptosis and depleted levels of c-Myc, STAT3, NF-κB, eIF4F, anti-apoptotic proteins, and pro-stemness proteins. Our findings showed the promise of CADPE for treating CRC and suggested a rational polytherapy that disables c-Myc, STAT3, NF-κB, and eIF4F for killing CRC residual disease.


Assuntos
Ácidos Cafeicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Desenvolvimento de Medicamentos/métodos , Descoberta de Drogas/métodos , Animais , Ácidos Cafeicos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Nus , Transdução de Sinais
17.
J Nat Prod ; 83(9): 2686-2695, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32864967

RESUMO

The new alkaloids marinacarbolines E-Q (1-10, 12-14), caerulomycin N (15), and actinoallonaphthyridine A (16), together with the known marinacarboline C (11) and cyanogramide (17), were isolated from the actinomycete Actinoalloteichus sp. ZZ1866. The structures of the isolated compounds were elucidated based on their HRESIMS data, extensive NMR spectroscopic analyses, Mosher's method, ECD calculations, single-crystal X-ray diffraction analysis, and chemical degradation studies. Marinacarbolines E-L (1-8) share an indole-pyridone-imidazole tetracyclic skeleton, which is the first example of this kind of skeleton. Caerulomycin N (15) and cyanogramide (17) exhibited cytotoxic activity against both human glioma U251 and U87MG cells with IC50 values of 2.0-7.2 µM. Marinacarbolines E (1), G (3), I (5), and M (9) showed cytotoxic activity against U87MG cells with IC50 values of 2.3-8.9 µM.


Assuntos
Actinobacteria/química , Alcaloides/química , Alcaloides/farmacologia , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Dicroísmo Circular , Fungos/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Difração de Raios X
18.
Mar Drugs ; 18(8)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722304

RESUMO

New streptothiazolidine A (1), streptodiketopiperazines A (2) and B (3), and (S)-1-(3-ethylphenyl)-1,2-ethanediol (4), together with eight known compounds (5-12), were isolated from the Mariana Trench sediment-associated actinomycete Streptomyces sp. SY1965. The racemic mixtures of (±)-streptodiketopiperazine (2 and 3) and (±)-1-(3-ethylphenyl)-1,2-ethanediol (4 and 5) were separated on a chiral high-performance liquid chromatography (HPLC) column. Structures of the new compounds were elucidated by their high-resolution electrospray ionization mass spectroscopy (HRESIMS) data and extensive nuclear magnetic resonance (NMR) spectroscopic analyses. Streptothiazolidine A is a novel salicylamide analogue with a unique thiazolidine-contained side chain and its absolute configuration was established by a combination of nuclear Overhauser effect spectroscopy (NOESY) experiment, electronic circular dichroism (ECD) and 13C NMR calculations. New streptothiazolidine A (1) and streptodiketopiperazines A (2) and B (3) showed antifungal activity against Candida albicans with MIC values of 47, 42, and 42 g/mL, respectively.


Assuntos
Actinobacteria/metabolismo , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida albicans/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
19.
Mar Drugs ; 18(5)2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32423167

RESUMO

Mariana Trench sediments are enriched in microorganisms, however, the structures and bioactivities of their secondary metabolites are not very known. In this study, a fungus Penicillium sp. SY2107 was isolated from a sample of Mariana Trench sediment collected at a depth of 11000 m and an extract prepared from the culture of this fungus in rice medium showed antimicrobial activities. Chemical investigation on this active extract led to the isolation of 16 compounds, including one novel meroterpenoid, named andrastone C. Structure of the new compound was elucidated based on high-resolution electrospray ionization mass spectroscopy (HRESIMS) data, extensive nuclear magnetic resonance (NMR) spectroscopic analyses and a single crystal X-ray diffraction. The crystal structure of a known meroterpenoid andrastone B was also reported in this study. Both andrastones B and C exhibited antimicrobial activities against methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans with minimum inhibitory concentration (MIC) values in a range from 6 to 13 g/mL.


Assuntos
Antibacterianos/farmacologia , Penicillium/química , Extratos Vegetais/farmacologia , Microbiologia do Solo , Antibacterianos/química , Candida albicans/efeitos dos fármacos , China , Escherichia coli/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oceanos e Mares , Extratos Vegetais/química , Relação Estrutura-Atividade
20.
Nat Prod Res ; 34(7): 1046-1050, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30580590

RESUMO

Two diketopiperazines were isolated from a culture of the marine-derived actinomycete Streptomyces sp. ZZ446. Their structures were elucidated as maculosin (1) and maculosin-O-α-L-rhamnopyranoside (2) based on their NMR and HRESIMS data, specific rotation, and chemical degradation. Maculosin-O-α-L-rhamnopyranoside (2) is a new diketopiperazine glycoside, a structural class not reported previously from the natural sources. Both compounds showed antimicrobial activity against methicillin-resistant Staphylococcus aureus, Escherichia coli, and Candida albicans with MIC values in a range from 26.0 to 37.0 µg/mL.[Formula: see text].


Assuntos
Dicetopiperazinas/isolamento & purificação , Glicosídeos/isolamento & purificação , Streptomyces/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Dicetopiperazinas/química , Escherichia coli/efeitos dos fármacos , Glicosídeos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Peptídeos Cíclicos , Piperazinas
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