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1.
Nat Immunol ; 18(3): 293-302, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28092373

RESUMEN

The aggregation of hypertrophic macrophages constitutes the basis of all granulomatous diseases, such as tuberculosis or sarcoidosis, and is decisive for disease pathogenesis. However, macrophage-intrinsic pathways driving granuloma initiation and maintenance remain elusive. We found that activation of the metabolic checkpoint kinase mTORC1 in macrophages by deletion of the gene encoding tuberous sclerosis 2 (Tsc2) was sufficient to induce hypertrophy and proliferation, resulting in excessive granuloma formation in vivo. TSC2-deficient macrophages formed mTORC1-dependent granulomatous structures in vitro and showed constitutive proliferation that was mediated by the neo-expression of cyclin-dependent kinase 4 (CDK4). Moreover, mTORC1 promoted metabolic reprogramming via CDK4 toward increased glycolysis while simultaneously inhibiting NF-κB signaling and apoptosis. Inhibition of mTORC1 induced apoptosis and completely resolved granulomas in myeloid TSC2-deficient mice. In human sarcoidosis patients, mTORC1 activation, macrophage proliferation and glycolysis were identified as hallmarks that correlated with clinical disease progression. Collectively, TSC2 maintains macrophage quiescence and prevents mTORC1-dependent granulomatous disease with clinical implications for sarcoidosis.


Asunto(s)
Granuloma/inmunología , Macrófagos/inmunología , Complejos Multiproteicos/metabolismo , Sarcoidosis/inmunología , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Línea Celular , Quinasa 4 Dependiente de la Ciclina/metabolismo , Progresión de la Enfermedad , Granuloma/tratamiento farmacológico , Humanos , Macrófagos/efectos de los fármacos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Interferente Pequeño/genética , Sarcoidosis/tratamiento farmacológico , Transducción de Señal , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de Tumor/genética
2.
J Nat Prod ; 86(10): 2270-2282, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37792632

RESUMEN

Persea americana Mill. (Lauraceae), commonly known as avocado, is a well-known food because of its nutrition and health benefits. The seeds of avocado are major byproducts, and thus their phytochemicals and bioactivities have been of interest for study. The chemical components of avocado seeds were investigated by using UPLC-qTOF-MS/MS-based molecular networking, resulting in the isolation of seven new oxindole alkaloids (1-7) and two new benzoxazinone alkaloids (8 and 9). The chemical structures of the isolated compounds were identified by the analysis of NMR data in combination with computational approaches, including NMR and ECD calculations. Bioactivities of the isolated compounds toward silent information regulation 2 homologue-1 (SIRT1) in HEK293 cells were assessed. The results showed that compound 1 had the most potent effect on SIRT1 activation with an elevated NAD+/NADH ratio with potential for further investigation as an anti-aging agent.


Asunto(s)
Alcaloides , Persea , Humanos , Persea/química , Oxindoles/farmacología , Benzoxazinas/análisis , Espectrometría de Masas en Tándem , Sirtuina 1 , Células HEK293 , Semillas/química , Alcaloides/farmacología , Alcaloides/análisis , Extractos Vegetales/química
3.
J Lipid Res ; 63(3): 100178, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35143844

RESUMEN

Cholesterol is an essential component of mammalian cell membranes whose subcellular concentration and function are tightly regulated by de novo biosynthesis, transport, and storage. Although recent reports have suggested diverse functions of cellular cholesterol in different subcellular membranes, systematic investigation of its site-specific roles has been hampered by the lack of a methodology for spatiotemporal manipulation of cellular cholesterol levels. Here, we report the development of a new cholesterol depletion system that allows for spatiotemporal manipulation of intracellular cholesterol levels. This system utilizes a genetically encoded cholesterol oxidase whose intrinsic membrane binding activity is engineered in such a way that its membrane targeting can be controlled in a spatiotemporally specific manner via chemically induced dimerization. In combination with in situ quantitative imaging of cholesterol and signaling activity measurements, this system allows for unambiguous determination of site-specific functions of cholesterol in different membranes, including the plasma membrane and the lysosomal membrane.


Asunto(s)
Colesterol , Lisosomas , Animales , Membrana Celular/metabolismo , Colesterol/metabolismo , Endosomas/metabolismo , Membranas Intracelulares/metabolismo , Lisosomas/metabolismo , Mamíferos/metabolismo
4.
J Biol Chem ; 297(5): 101303, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34655614

RESUMEN

As a central player in the canonical TGF-ß signaling pathway, Smad2 transmits the activation of TGF-ß receptors at the plasma membrane (PM) to transcriptional regulation in the nucleus. Although it has been well established that binding of TGF-ß to its receptors leads to the recruitment and activation of Smad2, the spatiotemporal mechanism by which Smad2 is recruited to the activated TGF-ß receptor complex and activated is not fully understood. Here we show that Smad2 selectively and tightly binds phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) in the PM. The PI(4,5)P2-binding site is located in the MH2 domain that is involved in interaction with the TGF-ß receptor I that transduces TGF-ß-receptor binding to downstream signaling proteins. Quantitative optical imaging analyses show that PM recruitment of Smad2 is triggered by its interaction with PI(4,5)P2 that is locally enriched near the activated TGF-ß receptor complex, leading to its binding to the TGF-ß receptor I. The PI(4,5)P2-binding activity of Smad2 is essential for the TGF-ß-stimulated phosphorylation, nuclear transport, and transcriptional activity of Smad2. Structural comparison of all Smad MH2 domains suggests that membrane lipids may also interact with other Smad proteins and regulate their function in diverse TGF-ß-mediated biological processes.


Asunto(s)
Fosfatidilinositol 4,5-Difosfato/metabolismo , Transducción de Señal , Proteína Smad2/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Transporte Activo de Núcleo Celular , Células HeLa , Humanos , Fosfatidilinositol 4,5-Difosfato/genética , Unión Proteica , Receptor Tipo I de Factor de Crecimiento Transformador beta/genética , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Proteína Smad2/genética , Factor de Crecimiento Transformador beta/genética
5.
Blood ; 136(4): 387-400, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32344427

RESUMEN

Fusion proteins involving Nucleoporin 98 (NUP98) are recurrently found in acute myeloid leukemia (AML) and are associated with poor prognosis. Lack of mechanistic insight into NUP98-fusion-dependent oncogenic transformation has so far precluded the development of rational targeted therapies. We reasoned that different NUP98-fusion proteins deregulate a common set of transcriptional targets that might be exploitable for therapy. To decipher transcriptional programs controlled by diverse NUP98-fusion proteins, we developed mouse models for regulatable expression of NUP98/NSD1, NUP98/JARID1A, and NUP98/DDX10. By integrating chromatin occupancy profiles of NUP98-fusion proteins with transcriptome profiling upon acute fusion protein inactivation in vivo, we defined the core set of direct transcriptional targets of NUP98-fusion proteins. Among those, CDK6 was highly expressed in murine and human AML samples. Loss of CDK6 severely attenuated NUP98-fusion-driven leukemogenesis, and NUP98-fusion AML was sensitive to pharmacologic CDK6 inhibition in vitro and in vivo. These findings identify CDK6 as a conserved, critical direct target of NUP98-fusion proteins, proposing CDK4/CDK6 inhibitors as a new rational treatment option for AML patients with NUP98-fusions.


Asunto(s)
Quinasa 6 Dependiente de la Ciclina/metabolismo , Sistemas de Liberación de Medicamentos , Leucemia Mieloide Aguda/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas de Fusión Oncogénica/metabolismo , Animales , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/genética , Perfilación de la Expresión Génica , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Ratones , Proteínas de Complejo Poro Nuclear/genética , Proteínas de Fusión Oncogénica/genética
6.
BMC Infect Dis ; 22(1): 607, 2022 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-35810277

RESUMEN

OBJECTIVES: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are the commonest bacterial causes of sexually transmitted infections in humans with high incidence of co-infection. Treatment with high doses of ceftriaxone (CRO) and cefixime (CFM) is strongly recommended due to the reduced drug susceptibility of NG. However, their safety and efficacy have not been confirmed. We compared the safety and efficacy of a single 1 g intravenous (IV) dose of ceftriaxone (CRO) plus doxycycline (DOX) versus a single 800 mg oral dose of cefixime (CFM) plus DOX for the treatment of NG-CT co-infection. METHODS: An open-label randomized controlled trial was conducted on 125 individuals aged > 18 years with untreated gonorrhea and chlamydia to compare a single 1 g intravenous dose of CRO + DOX and a single 800 mg oral dose of CFM + DOX. The primary outcome was the clearance of NG from all the initially infected sites. Secondary outcomes included symptom resolution, changes in the serum clearance levels, glomerular filtration rate, and antibiotic minimum inhibitory concentrations. RESULTS: Both regimens were highly effective in treating gonorrhea with success rates of 96.7% (95% confidence interval [CI] 88.8-99.1%) for CRO and 95.3% (95% CI 87.1-98.4%) for CFM. However, CRO + DOX was superior to CFM + DOX for the treatment of NG-CT co-infection (odds ratio 4.41, 95% CI 1.11-25.7). The safety profiles of the two regimens were similar. CONCLUSIONS: CRO + DOX was superior to CFM + DOX for the treatment of NG-CT co-infection. CFM + DOX may be indicated in patients with CRO allergy and in settings where CRO is unavailable. Trial registration ClinicalTrials.gov (NCT05216744) on 31/01/22.


Asunto(s)
Infecciones por Chlamydia , Coinfección , Gonorrea , Antibacterianos/farmacología , Cefixima/farmacología , Cefixima/uso terapéutico , Ceftriaxona/farmacología , Infecciones por Chlamydia/diagnóstico , Infecciones por Chlamydia/tratamiento farmacológico , Chlamydia trachomatis , Coinfección/tratamiento farmacológico , Doxiciclina/uso terapéutico , Gonorrea/epidemiología , Humanos , Neisseria gonorrhoeae
7.
J Nat Prod ; 85(1): 70-82, 2022 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-35040315

RESUMEN

The cumulative effects of cell damage result in aging, which gradually decreases human function in various aspects and leads to multiple age-related chronic diseases. To overcome the adverse effects of aging, silent mating type information regulation 2 homologue (SIRT1) activators are promising bioactive compounds that mimic calorie restriction to improve quality of life and prevent aging. In this study, 11 new flavonostilbenes (1-11) and three known compounds (12-14) were purified from stems of Rhamnoneuron balansae. The structures of the new compounds were determined using extensive data from spectroscopic methods, including NMR and HRESIMS. Their absolute configurations were deduced by ECD calculations with coupling constant analysis. All of the isolated new compounds (1-11) were evaluated for their effects on SIRT1 deacetylase activity, the NAD+/NADH ratio, and the AMP-activated protein kinase activation level in cell-based assays. The results showed that rhamnoneuronal D (1) exhibits promising biological activity in several in vitro models related to SIRT1 and suggest it is a potential natural-product-based antiaging agent.


Asunto(s)
Tallos de la Planta/química , Sirtuina 1/efectos de los fármacos , Estilbenos/aislamiento & purificación , Adenilato Quinasa/metabolismo , Animales , Espectroscopía de Resonancia Magnética con Carbono-13 , Activación Enzimática , Humanos , NAD/metabolismo , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray , Estilbenos/farmacología , Thymelaeaceae/química
8.
Harm Reduct J ; 19(1): 45, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35562829

RESUMEN

INTRODUCTION: The emergence of widespread amphetamine-type stimulants (ATSs) usage has created significant challenges for drug control and treatment policies in Southeast Asian countries. This study analyses the development of drug policies and examines current treatment program constraints in Vietnam to deal with ATS misuse. The aim was to gain insights that may be useful for national and international drug-related policy development and revision. METHODS: A desk review of national policy documents and 22 in-depth key informant interviews were conducted from 2019 to 2021. Thematic content analysis was employed to identify key themes and their connections. RESULTS: Analysis identified Vietnam's 30-year history of developing policies and formulating strategies to reduce supply, demand, and harm from illicit drugs. With the increasing number of people who use ATS (PWUA), Vietnam has recently promoted harsh policy and law enforcement to deter drug use and supply. This policy trend prevails in many Asian countries. The three main constraints in dealing with ATS misuse emerged from punitive and restrictive drug policies. First, the general public believed that Centre-based compulsory treatment (CCT) is the only appropriate treatment for all types of illicit drug addiction despite its low-quality service provision. The rigid drug policy has led to social persuasion with impractical expectations for CCT effectiveness. Second, the emphasis on punishment and detention has hampered new drug treatment service development in Vietnam. CCT has become monopolistic in the context of impoverished services. Third, people who use drugs tend to hide their needs and avoid formal treatment and support services, resulting in declined social coherence. CONCLUSION: While new drugs are constantly evolving, the current law enforcement approach potentially constrains expertise to adopt effective treatment services. This study suggests that the top-down policing mechanism presently hinders the development of an appropriate intervention strategy for ATS misuse and diminishes social support to service providers.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Drogas Ilícitas , Trastornos Relacionados con Sustancias , Anfetamina , Humanos , Formulación de Políticas , Política Pública , Trastornos Relacionados con Sustancias/terapia , Vietnam
9.
J Therm Spray Technol ; 31(1-2): 269-281, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38624803

RESUMEN

A typical structure of thermal spray coatings consisted of molten particles, semi-molten particles, oxides, pores, and cracks. These factors caused the porosity of sprayed coatings, leading to a significant influence on the coating properties, especially their wear-corrosion resistance. In this study, a post-spray sealing treatment of Cr3C2-NiCr/Al2O3-TiO2 plasma-sprayed coatings was carried out, and then, their corrosion properties were evaluated, before and after the treatment. For the sealing process, aluminum phosphate (APP) containing Al2O3 nanoparticles (~10 nm) was used. The permeability of APP into the sprayed coating was analyzed by SEM-EDS. The treatment efficiency for porosity and corrosion resistance of sprayed coatings was evaluated by electrochemical measurements, such as the potentiodynamic polarization and electrochemical impedance spectroscopy. The wear-corrosion resistance of the coating was examined in 3.5 wt.% NaCl circulation solution containing 0.25% SiO2 particles. The sealing efficiency was evaluated by the percentage of the treated open pores in the coating. The obtained results showed that APP penetrated deeply through the coating and the incorporation of Al2O3 nanoparticles into APP sealant improved the sealing efficiency by 20% of open pores in comparison with the sealant without nano-Al2O3. The effect of the post-treatment on corrosion protection of the sprayed coating has been discussed.

10.
Bioorg Chem ; 117: 105445, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34717238

RESUMEN

During an attempt to discover insulin mimetics, thirteen new triterpenoid saponins (1-13), including three phytolaccagenic acids (1, 2, and 12) and ten serjanic acids (3-11 and 13), as aglycones were isolated from a 70% ethanol extract of leaves and stems from Pericampylus glaucus. The chemical structures of compounds 1-13 were determined through spectroscopic data analysis, including NMR, IR, and HRESIMS. All isolated compounds (1-13) were evaluated using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent-tagged glucose probe to determine their stimulatory effects on glucose uptake in differentiated 3 T3-L1 adipocyte cells. Consequently, four compounds (4, 7, 11, and 12) exhibited stimulatory effects on glucose uptake.


Asunto(s)
Hipoglucemiantes/farmacología , Insulina/metabolismo , Menispermaceae/química , Extractos Vegetales/farmacología , Saponinas/farmacología , Triterpenos/farmacología , Células 3T3-L1 , Animales , Relación Dosis-Respuesta a Droga , Glucosa/metabolismo , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Ratones , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Tallos de la Planta/química , Saponinas/química , Saponinas/aislamiento & purificación , Relación Estructura-Actividad , Triterpenos/química , Triterpenos/aislamiento & purificación
11.
Haematologica ; 105(2): 435-447, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31123029

RESUMEN

Recurrent gain-of-function mutations in the transcription factors STAT5A and much more in STAT5B were found in hematopoietic malignancies with the highest proportion in mature T- and natural killer-cell neoplasms (peripheral T-cell lymphoma, PTCL). No targeted therapy exists for these heterogeneous and often aggressive diseases. Given the shortage of models for PTCL, we mimicked graded STAT5A or STAT5B activity by expressing hyperactive Stat5a or STAT5B variants at low or high levels in the hematopoietic system of transgenic mice. Only mice with high activity levels developed a lethal disease resembling human PTCL. Neoplasia displayed massive expansion of CD8+ T cells and destructive organ infiltration. T cells were cytokine-hypersensitive with activated memory CD8+ T-lymphocyte characteristics. Histopathology and mRNA expression profiles revealed close correlation with distinct subtypes of PTCL. Pronounced STAT5 expression and activity in samples from patients with different subsets underline the relevance of JAK/STAT as a therapeutic target. JAK inhibitors or a selective STAT5 SH2 domain inhibitor induced cell death and ruxolitinib blocked T-cell neoplasia in vivo We conclude that enhanced STAT5A or STAT5B action both drive PTCL development, defining both STAT5 molecules as targets for therapeutic intervention.


Asunto(s)
Leucemia , Linfoma de Células T Periférico , Animales , Linfocitos T CD8-positivos/metabolismo , Citocinas , Humanos , Linfoma de Células T Periférico/genética , Ratones , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Proteínas Supresoras de Tumor
12.
Int J Syst Evol Microbiol ; 70(8): 4698-4703, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32701426

RESUMEN

A Gram-stain-negative, non-motile, facultatively anaerobic and rod-shaped bacterial strain, designated PAMC 28131T, was isolated from a sea surface microlayer sample in the open water of the Pacific Ocean. Phylogenetic analysis of the 16S rRNA gene sequence of strain PAMC 28131T revealed an affiliation to the genus Sandaracinobacter with the closest species Sandaracinobacter sibiricus RB16-17T (sequence similarity of 98.2 %). Strain PAMC 28131T was able to grow optimally with 0.5-1.0 % NaCl and at pH 6.5-7.0 and 30 °C. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, an unidentified aminolipid, an unidentified glycolipid and an unidentified lipid. The major cellular fatty acids (>10 %) were C18 : 1 ω6c and/or C18 : 1 ω7c, (42.6 %), C17 : 1 ω6c (19.3 %) and C16 : 1 ω6c and/or C16 : 1 ω7c (15.8 %), and the respiratory quinone was Q-10. The genomic DNA G+C content was 65.3 mol%. The phylogenetic, phenotypic and chemotaxonomic data showed that strain PAMC 28131T could be clearly distinguished from S. sibiricus RB16-17T. Thus, strain PAMC 28131T should be classified as representing a novel species in the genus Sandaracinobacter, for which the name Sandaracinobacter neustonicus sp. nov. is proposed. The type strain is PAMC 28131T (=KCCM 43127T=JCM 30734T).


Asunto(s)
Filogenia , Agua de Mar/microbiología , Sphingomonadaceae/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Océano Pacífico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sphingomonadaceae/aislamiento & purificación
13.
J Nat Prod ; 83(12): 3661-3670, 2020 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-33256407

RESUMEN

With the advent of senolytic agents capable of selectively removing senescent cells in old tissues, the perception of age-associated diseases has been changing from being an inevitable to a preventable phenomenon of human life. In the search for materials with senolytic activity from natural products, six new flavonostilbenes (1-6), three new phenylethylchromanones (7-9), three new phenylethylchromones (10-12), and four known compounds (13-16) were isolated from the roots of Rhamnoneuron balansae. The chemical structures of these isolated compounds were determined based on the interpretation of spectroscopic data, including 1D and 2D NMR, ECD, and HRMS. The absolute configuration of compound 1 was also determined by a Mosher ester analysis and ECD calculations. Compounds 6-8 were shown to selectively destroy senescent cells, and the promoter activity of p16INK4A, a representative senescence marker, was reduced significantly by compound 6. The present results suggest the potential activity of flavonostilbene and phenylethylchromanone skeletons from R. balansae as new senolytics.


Asunto(s)
Senescencia Celular , Malvales/química , Fenoles/química , Raíces de Plantas/química , Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/química , Análisis Espectral/métodos
14.
J Nat Prod ; 83(4): 1265-1274, 2020 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-32237726

RESUMEN

During an effort to find insulin mimetic compounds, the leaves of Gymnema inodorum were shown to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. Bioassay-guided fractionation on a 70% ethanol extract of G. inodorum was applied to yield two new (1 and 2) and two known (8 and 9) oleanane triterpenoids with a methyl anthranilate moiety together with five further new oleanane triterpenoids (3-7). The chemical structures of all isolates were determined based on their spectroscopic data, including IR, UV, NMR, and mass spectrometric analysis. The isolated compounds (1-9) were determined for their stimulatory activities on glucose uptake in differentiated 3T3-L1 adipocyte cells using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent-tagged glucose probe. Three compounds (3, 5, and 9) showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Chemicals with a methyl anthranilate moiety have been considered as crucial contributors of flavor odor in foods, and quantitative analysis showed the content of compound 8 to be 0.90 ± 0.01 mg/g of the total extract. These results suggest that the leaves of G. inodorum have the potential to be used as an antidiabetic functional food or tea.


Asunto(s)
4-Cloro-7-nitrobenzofurazano/análogos & derivados , Desoxiglucosa/análogos & derivados , Hipoglucemiantes/farmacología , Insulina/farmacología , Ácido Oleanólico/análogos & derivados , Triterpenos/farmacología , Células 3T3-L1 , 4-Cloro-7-nitrobenzofurazano/química , 4-Cloro-7-nitrobenzofurazano/farmacología , Animales , Transporte Biológico/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Desoxiglucosa/química , Desoxiglucosa/farmacología , Glucosa/análisis , Gymnema , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Insulina/química , Insulina/metabolismo , Ratones , Estructura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/farmacología , Hojas de la Planta , Triterpenos/química , Triterpenos/aislamiento & purificación
15.
Environ Monit Assess ; 192(7): 411, 2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32494862

RESUMEN

In this article, the authors apply the relative air pollution index (RAPI) proposed by Pham Ngoc Ho for aggregate assessment of daily air pollution level (RAPId) using data from 3 daily standards (1, 8, and 24 h) of each country's standard, including Vietnam Technical Regulation QCVN 05:2013/MONRE. By using the automated data of ambient air at 3 monitoring stations in Cam Pha coal mining area, Quang Ninh province in 2018, results of the frequency of pollution by month (f%) have shown that overall, the air quality in dry season (October-March) is worse than that in rainy season (April-September). Results of pollution frequency by month in a year f% also indicate that air pollution in 2018 at 3 stations is mostly at level I (no pollution) with f% ranged from 10 to 58.3%, but pollution level II-IV (light pollution-very heavy pollution) also happened as f% fluctuated from 20 to 42% in some months. Comparing with air quality assessment in 2011-2015 at this area by periodic monitoring equipment of Quang Ninh Center for Environmental Monitoring, results in 2018 have shown that individual index of RAPI is consistent with the current status of air quality with high accuracy. To compare with RAPId, we used VN_AQId index of the Vietnam Environment Administration (VEA). Comparison results show that both indices do not encounter eclipsing effect. However, ambiguous effect occurred in the case of VN_AQId index (warning not suitable for reality in some cases). In addition, advantages and limitations of these two methods have been analyzed and explained in detail.


Asunto(s)
Contaminantes Atmosféricos , Minas de Carbón , Monitoreo del Ambiente , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Vietnam
16.
J Nat Prod ; 82(8): 2201-2210, 2019 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-31393125

RESUMEN

Melicope pteleifolia has long been consumed as a popular vegetable and tea in Southeast Asian countries, including Malaysia and southern mainland China, and is effective in the treatment of colds and inflammation. In the search for active metabolites that can explain its traditional use as an antipyretic, six new phloroacetophenone derivatives (3-8) along with seven known compounds (1, 2, and 9-13) were isolated from the leaves of M. pteleifolia. Their chemical structures were confirmed by extensive spectroscopic analysis including NMR, IR, ECD, and HRMS. All compounds isolated from the leaves of M. pteleifolia (1-13) have a phloroacetophenone skeleton. Notably, the new compound 8 contains an additional cyclobutane moiety in its structure. The bioactivities of the isolated compounds were evaluated, and compounds 1, 6, and 7 inhibited tumor necrosis factor-α-induced prostaglandin E2. Moreover, the major constituent, 3,5-di-C-ß-d-glucopyranosyl phloroacetophenone (1), was found to be responsible for the antipyretic activity of M. pteleifolia based on in vivo experiments.


Asunto(s)
Analgésicos/farmacología , Hojas de la Planta/química , Rutaceae/química , Animales , Células Cultivadas , Humanos , Masculino , Ratones , Ratones Endogámicos ICR , Estructura Molecular , Plantas Comestibles/química , Análisis Espectral/métodos
17.
J Nat Prod ; 82(4): 702-713, 2019 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-30888811

RESUMEN

Porcine epidemic diarrhea virus (PEDV), a serious swine epidemic, has been rampant in Asia since the 1990s. Despite the widespread use of PEDV vaccines, the occurrence of PEDV variants requires the discovery of new substances that inhibit these viruses. During a search for PEDV inhibitory materials from natural sources, seven new sabphenosides (1-7) and a new flavonoid (8), as well as eight known phenolic compounds (9-16), were obtained from the leaves of Sabia limoniacea. The structural determination of the new phenolic derivatives (1-8) was accomplished using comprehensive spectroscopic methods. Their absolute configurations were assigned by a combination of the ECD exciton chirality method following selective reduction and calculation of their ECD spectra. The bioactivities of the isolated compounds were measured based on their abilities to inhibit viral replication of PEDV. Among the test compounds, 15 and 16 exhibited the most promising antiviral activities, with IC50 values of 7.5 ± 0.7 µM and 8.0 ± 2.5 µM against PEDV replication. This study suggests that compounds 15 and 16 could serve as new scaffolds for the treatment of PEDV infection through the inhibition of PEDV replication.


Asunto(s)
Antivirales/aislamiento & purificación , Antivirales/farmacología , Magnoliopsida/química , Fenoles/aislamiento & purificación , Fenoles/farmacología , Hojas de la Planta/química , Virus de la Diarrea Epidémica Porcina/efectos de los fármacos , Animales , Antivirales/química , Chlorocebus aethiops , Efecto Citopatogénico Viral/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fenoles/química , Virus de la Diarrea Epidémica Porcina/fisiología , Prenilación , Porcinos , Células Vero , Replicación Viral/efectos de los fármacos
18.
J Nat Prod ; 82(12): 3249-3266, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31763839

RESUMEN

The major class of bioactive metabolites in Gymnema sylvestre, a popular Ayurvedic medicinal plant for the treatment of diabetes mellitus, is oleanane triterpenoids. In this study, a targeted, biosynthesis-inspired approach using UHPLC-qTOF/MS was implemented to elucidate the whole chemical profile of this plant for the standardization of the Vietnamese G. sylvestre variety. The known compounds were first determined to identify the building blocks of the biosynthetic intermediates and the construction rules for synthesizing oleanane triterpenoids in the plant. These blocks were recombined to build a virtual library of all reasonable compounds consistent with the deduced construction rules. Various techniques, including relative mass defect filtering, multiple key ion analysis, mass fragmentation analysis, and comparison with standard references, were applied to determine the presence of these predicted compounds. Conventional isolation and structure elucidation of six of the new compounds were carried out to identify the new building blocks and validate the assignments. Consequently, 119 peaks were quickly assigned to oleanane triterpenoids, and among them, 77 peaks were predicted to be new compounds based on their molecular formulas and mass fragmentation patterns. All the identified metabolites were then classified into different layers to analyze their logical relationships, and a multilayered chemical profile of the oleanane triterpenoids was constructed. This new approach is expected to be practical for characterizing structures of modular secondary metabolites, such as triterpenoid saponins, and for proposing biosynthetic relationships among compounds of the same class of metabolites in medicinal plants.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Gymnema sylvestre/metabolismo , Ácido Oleanólico/análogos & derivados , Análisis Espectral/métodos , Triterpenos/metabolismo , Glicósidos/metabolismo , Estructura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/metabolismo , Triterpenos/química
19.
Mar Drugs ; 17(3)2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30836593

RESUMEN

Ecklonia cava is edible seaweed that is found in Asian countries, such as Japan and Korea; and, its major components include fucoidan and phlorotannins. Phlorotannins that are isolated from E. cava are well-known to have an antioxidant effect and strong antiviral activity against porcine epidemic diarrhea virus (PEDV), which has a high mortality rate in piglets. In this study, the bioactive components were determined based on two different approaches: (i) bio-guided isolation using the antiviral activity against the H1N1 viral strain, which is a representative influenza virus that originates from swine and (ii) high-resolution mass spectrometry-based dereplication, including relative mass defects (RMDs) and HPLC-qTOFMS fragmentation analysis. The EC70 fraction showed the strongest antiviral activity and contained thirteen phlorotannins, which were predicted by dereplication. Ten compounds were directly isolated from E. cava extract and then identified. Moreover, the dereplication method allowed for the discovery of two new phlorotannins. The structures of these two isolated compounds were elucidated using NMR techniques and HPLC-qTOFMS fragmentation analysis. In addition, molecular modelling was applied to determine the absolute configurations of the two new compounds. The antiviral activities of seven major phlorotannins in active fraction were evaluated against two influenza A viral strains (H1N1 and H9N2). Six of the compounds showed moderate to strong effects on both of the viruses and phlorofucofuroeckol A (12), which showed an EC50 value of 13.48 ± 1.93 µM, is a potential active antiviral component of E. cava.


Asunto(s)
Antivirales/farmacología , Productos Biológicos/farmacología , Phaeophyceae/química , Algas Marinas/química , Taninos/farmacología , Antivirales/química , Antivirales/aislamiento & purificación , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H9N2 del Virus de la Influenza A/efectos de los fármacos , Espectrometría de Masas en Tándem/métodos , Taninos/química , Taninos/aislamiento & purificación
20.
Chem Pharm Bull (Tokyo) ; 67(1): 41-46, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30606949

RESUMEN

Bio-guided fractionation of the 70% ethanol extract of Belamcanda chinensis (L.) DC. revealed four new compounds, including 6″-O-acetylembinin (5), 3″-O-acetylembinin (6), irigenin 3'-O-ß-glucopyranoside (8), and 2'-acetyl-1,3-O-diferuloylsucrose (9), along with five known compounds (1-4, 7). Their chemical structures were determined using extensive NMR data, mass spectroscopy, and comparison with published literature. Among the isolates, compounds 1 and 4-7 achieved good regulation of the growth and proliferation of vascular smooth muscle cells.


Asunto(s)
Iridaceae/química , Isoflavonas/farmacología , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Componentes Aéreos de las Plantas/química , Extractos Vegetales/farmacología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Isoflavonas/química , Isoflavonas/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad
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