Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 192
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Int J Cancer ; 154(6): 1111-1123, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-37842828

RESUMEN

Effective screening and early detection are critical to improve the prognosis of gastric cancer (GC). Our study aims to explore noninvasive multianalytical biomarkers and construct integrative models for preliminary risk assessment and GC detection. Whole genomewide methylation marker discovery was conducted with CpG tandems target amplification (CTTA) in cfDNA from large asymptomatic screening participants in a high-risk area of GC. The methylation and mutation candidates were validated simultaneously using one plasma from patients at various gastric lesion stages by multiplex profiling with Mutation Capsule Plus (MCP). Helicobacter pylori specific antibodies were detected with a recomLine assay. Integrated models were constructed and validated by the combination of multianalytical biomarkers. A total of 146 and 120 novel methylation markers were found in CpG islands and promoter regions across the genome with CTTA. The methylation markers together with the candidate mutations were validated with MCP and used to establish a 133-methylation-marker panel for risk assessment of suspicious precancerous lesions and GC cases and a 49-methylation-marker panel as well as a 144-amplicon-mutation panel for GC detection. An integrated model comprising both methylation and specific antibody panels performed better for risk assessment than a traditional model (AUC, 0.83 and 0.63, P < .001). A second model for GC detection integrating methylation and mutation panels also outperformed the traditional model (AUC, 0.82 and 0.68, P = .005). Our study established methylation, mutation and H. pylori-specific antibody panels and constructed two integrated models for risk assessment and GC screening. Our findings provide new insights for a more precise GC screening strategy in the future.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Metilación de ADN , Detección Precoz del Cáncer , Biomarcadores , Medición de Riesgo , Helicobacter pylori/genética , Biomarcadores de Tumor/genética , Islas de CpG , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/patología
2.
Inorg Chem ; 62(33): 13328-13337, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37556609

RESUMEN

It is a challenging task to utilize efficient electrocatalytic metal hydroxide-based materials for the oxygen evolution reaction (OER) in order to produce clean hydrogen energy through water splitting, primarily due to the restricted availability of active sites and the undesirably high adsorption energies of oxygenated species. To address these challenges simultaneously, we intentionally engineer a hollow star-shaped Ag/CoMo-LDH heterostructure as a highly efficient electrocatalytic system. This design incorporates a considerable number of heterointerfaces between evenly dispersed Ag nanoparticles and CoMo-LDH nanosheets. The heterojunction materials have been prepared using self-assembly, in situ transformation, and spontaneous redox processes. The nanosheet-integrated hollow architecture can prevent active entities from agglomeration and facilitate mass transportation, enabling the constant exposure of active sites. Specifically, the powerful electronic interaction within the heterojunction can successfully regulate the Co3+/Co2+ ratio and the d-band center, resulting in rational optimization of the adsorption and desorption of the intermediates on the site. Benefiting from its well-defined multifunctional structures, the Ag0.4/CoMo-LDH with optimal Ag loading exhibits impressive OER activity, the overpotential being 290 mV to reach a 10 mA cm-2 current density. The present study sheds some new insights into the electron structure modulation of hollow heterostructures toward rationally designing electrocatalytic materials for the OER.

3.
BMC Biol ; 20(1): 186, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-36002843

RESUMEN

BACKGROUND: Karat (Musa troglodytarum L.) is an autotriploid Fe'i banana of the Australimusa section. Karat was domesticated independently in the Pacific region, and karat fruit are characterized by a pink sap, a deep yellow-orange flesh colour, and an abundance of ß-carotene. Karat fruit showed non-climacteric behaviour, with an approximately 215-day bunch filling time. These features make karat a valuable genetic resource for studying the mechanisms underlying fruit development and ripening and carotenoid biosynthesis. RESULTS: Here, we report the genome of M. troglodytarum, which has a total length of 603 Mb and contains 37,577 predicted protein-coding genes. After divergence from the most recent common ancestors, M. troglodytarum (T genome) has experienced fusion of ancestral chromosomes 8 and 9 and multiple translocations and inversions, unlike the high synteny with few rearrangements found among M. schizocarpa (S genome), M. acuminata (A genome) and M. balbisiana (B genome). Genome microsynteny analysis showed that the triplication of MtSSUIIs due to chromosome rearrangement may lead to the accumulation of carotenoids and ABA in the fruit. The expression of duplicated MtCCD4s is repressed during ripening, leading to the accumulation of α-carotene, ß-carotene and phytoene. Due to a long terminal repeat (LTR)-like fragment insertion upstream of MtERF11, karat cannot produce large amounts of ethylene but can produce ABA during ripening. These lead to non-climacteric behaviour and prolonged shelf-life, which contributes to an enrichment of carotenoids and riboflavin. CONCLUSIONS: The high-quality genome of M. troglodytarum revealed the genomic basis of non-climacteric behaviour and enrichment of carotenoids, riboflavin, flavonoids and free galactose and provides valuable resources for further research on banana domestication and breeding and the improvement of nutritional and bioactive qualities.


Asunto(s)
Musa , Carotenoides/metabolismo , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Musa/genética , Musa/metabolismo , Fitomejoramiento , Riboflavina/genética , Riboflavina/metabolismo , beta Caroteno/metabolismo
4.
Org Biomol Chem ; 17(3): 555-560, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30574992

RESUMEN

Ciliatasecones A-C (1-3), three rearranged limonoids with a novel ring-seco model and an unprecedented cycle system, were isolated from the root bark of Toona ciliata var. yunnanensis. Ciliatasecones A-B (1-2) share a novel cyclopenta[b]furan ring C/D system through C-9/11-seco and C-11/14 ether linkage. Ciliatasecone C (3) was found to possess a rare rearranged six-membered lactone ring B between C-7 and C-9. Plausible biogenetic pathway speculation indicated that C-9/11 cleavage and oxygen bridge formation played the key roles in the framework rearrangement of 1-3.

5.
J Nat Prod ; 82(6): 1399-1404, 2019 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-30998015

RESUMEN

A synthesis-inspired chemical investigation of the leaves of Melicope ptelefolia led to the isolation of evodialones A-D (1-4), four rearranged acetophenone stereoisomers possessing a prenylated acylcyclopentenone skeleton with three stereogenic carbons. Evodialones C and D (3 and 4) are new minor constituents. The chiral-phase HPLC resolution gave (+)-1-4 and (-)-1-4, eight enantiomers forming a complete stereoisomer library. Their absolute configurations were elucidated via extensive spectroscopic data and a modified Mosher's method. The relationship between the chiral structures and their NMR and ECD data is discussed. Compounds (±)-1, -2, and -4 have significant protective effects on high-glucose-induced oxidative stress in human vein endothelial cells.


Asunto(s)
Acetofenonas/química , Células Endoteliales/química , Hojas de la Planta/química , Rutaceae/química , Cromatografía Líquida de Alta Presión , Humanos , Espectroscopía de Resonancia Magnética , Prenilación , Estereoisomerismo
6.
Bioorg Chem ; 84: 295-301, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30529847

RESUMEN

Artemisianins A-D (1-4), four stereoisomers of sesquiterpenoid dimers, forming via [4+2] cycloaddition from a 1, 10-seco-guaianolide dienophile and a guaianolide diene, along with two biosynthetically related precurors 5 and 6, were isolated from the famous traditional Chinese medicine Artemisia argyi. The structures of 1-4, including their absolute configurations, were elucidated by extensive spectroscopic data and ECD/TDDFT calculation analysis. Compounds 1-4 exhibited cytotoxicity with IC50 values ranging from 7.2 to 23.3 µM. The accumulation of Ca2+ in cytoplasm and enlarged endoplasmic reticulum (ER) indicated that 1 mediated HT-29 cancer cell apoptosis through improvement of ER-stress, which was further proved by unfolded protein response (UPR) pathway on basis of the upregulation of IRE1α, p-PERK, ATF6, and CHOP.


Asunto(s)
Apoptosis , Artemisia/química , Estrés del Retículo Endoplásmico , Sesquiterpenos/química , Apoptosis/efectos de los fármacos , Artemisia/metabolismo , Línea Celular Tumoral , Dimerización , Estrés del Retículo Endoplásmico/efectos de los fármacos , Humanos , Medicina Tradicional China , Conformación Molecular , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Estereoisomerismo
7.
Bioorg Chem ; 87: 409-416, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30921742

RESUMEN

Nine new spirocyclic acylphloroglucinol derivatives, hyperpatulols A-I (1-9), were characterized from the flowers of Hypericum patulum. Their structures were elucidated by the basic analysis of the obtained spectroscopic data, and their absolute configurations were assigned by both the electronic circular dichroism (ECD) exciton chirality method and ECD calculation. The evaluation of their anti-migration effects on U2-OS human osteosarcoma cells showed that compound 4 exhibited moderate inhibitory activity in a dose-dependent manner. Further pharmacological studies revealed that 4 could regulate the expression of the proteins Vimentin and E-cadherin.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Flores/química , Hypericum/química , Floroglucinol/farmacología , Compuestos de Espiro/farmacología , Antígenos CD/genética , Antígenos CD/metabolismo , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Floroglucinol/análogos & derivados , Floroglucinol/química , Compuestos de Espiro/química , Compuestos de Espiro/aislamiento & purificación , Relación Estructura-Actividad , Vimentina/genética , Vimentina/metabolismo
8.
BMC Cardiovasc Disord ; 18(1): 73, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29716519

RESUMEN

BACKGROUND: Centenarians refer to a special group who have outlived most of their fellows. Body shape and abdominal obesity have been identified as cardiovascular disease (CVD) risk factors. Our study aimed to evaluate the relationship between body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) and CVD risk factors among male and female centenarians in Hainan province. METHODS: Five hundred thirty-seven centenarians aged between 100 and 115 (Mage = 107 years old) years participated in this study. Each participant received a standardized questionnaire and physical examination. We measured anthropometric variables (BMI, WC, WHR, WHtR, SBP and DBP) and serum lipid (TC, TG, HDL-C and LDL-C). RESULTS: 76.9% (n = 413) of the study subjects were female. TC, TG, LDL-C and HDL-C were significantly higher in female group than that of male group. BMI, WC and WHtR were well-correlated with the CVD risk factors. The anthropometric measures were negatively related with HDL-C levels and positively related with the other CVD risk factors. CONCLUSIONS: Hainan centenarians were short in stature and underweight. Moreover, female centenarians were often pear-shaped, while male centenarians were often apple-shaped. Further, BMI, WC and WHtR were well-correlated with the serum lipid, and TC, TG, LDL-C and HDL-C were significantly higher in females than males. Also, BMI, WC and WHtR were closely related to the incidence of dyslipidemia in females, including high TG, high LDL-C and low HDL-C.


Asunto(s)
Antropometría , Enfermedades Cardiovasculares/epidemiología , Obesidad/epidemiología , Factores de Edad , Anciano de 80 o más Años , Biomarcadores/sangre , Presión Sanguínea , Estatura , Índice de Masa Corporal , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/fisiopatología , China/epidemiología , Femenino , Evaluación Geriátrica , Humanos , Lípidos/sangre , Masculino , Obesidad/sangre , Obesidad/diagnóstico , Obesidad/fisiopatología , Factores de Riesgo , Factores Sexuales , Circunferencia de la Cintura , Relación Cintura-Estatura , Relación Cintura-Cadera
9.
J Nat Prod ; 81(5): 1148-1153, 2018 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-29738260

RESUMEN

Peyronellones A and B (1 and 2), a pair of rare tetracyclic caged adducts of azaphilone with pyruvic acid, along with four new analogues (3-6), were isolated from solid cultures of the endophytic fungus Peyronellaea glomerata. Their structures were elucidated through spectroscopic analysis, and their absolute configurations were unambiguously determined by a combination of single-crystal X-ray crystallography, Rh2(OCOCF3)4-induced ECD experiments, ECD calculations, and modified Mosher methods. Compound 2 (5 µM) was found to have a significant hypoxia-protective effect that improved the survival rate of hypoxia/reoxygenation-treated human umbilical vein endothelial cells from 35% to 70%, which was equal to the potency of the positive control, verapamil. Flow cytometry analysis suggested 2 could inhibit H/R-induced late-stage apoptosis of this cell line.


Asunto(s)
Ascomicetos/química , Benzopiranos/farmacología , Hipoxia/tratamiento farmacológico , Pigmentos Biológicos/farmacología , Sustancias Protectoras/farmacología , Apoptosis/efectos de los fármacos , Benzopiranos/química , Células Cultivadas , Cristalografía por Rayos X/métodos , Endófitos/química , Células Endoteliales de la Vena Umbilical Humana , Humanos , Pigmentos Biológicos/química , Sustancias Protectoras/química , Ácido Pirúvico/química , Tasa de Supervivencia , Verapamilo/farmacología
10.
J Nat Prod ; 81(2): 378-386, 2018 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-29400471

RESUMEN

Ten new highly oxidized monomeric (1-8) and dimeric guaianolides (9 and 10), along with two known guaianolide derivatives (11 and 12), were isolated from the aerial parts of Chrysanthemum indicum using a bioassay-guided fractionation procedure. The new compounds were characterized by the basic analysis of the spectroscopic data obtained, and the absolute configurations were determined by both empirical approaches and ECD calculations. Inhibitory effects of 1-12 on nitric oxide production were investigated in lipopolysaccaride (LPS)-mediated RAW 264.7 cells, and most of them (1-8 and 11) displayed IC50 values in the range 1.4-9.7 µM. Moreover, a mechanistic study revealed that the potential anti-inflammatory activity of compound 1 appears to be mediated via suppression of an LPS-induced NF-κB pathway and down-regulation of MAPK activation.


Asunto(s)
Antiinflamatorios/química , Chrysanthemum/química , Sesquiterpenos de Guayano/química , Sesquiterpenos de Guayano/farmacología , Animales , Antiinflamatorios/farmacología , Línea Celular , Lipopolisacáridos/farmacología , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Células RAW 264.7
11.
Med Sci Monit ; 24: 183-189, 2018 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-29315280

RESUMEN

BACKGROUND Gremlin has been reported to be up-regulated in glomerular mesangial cells in diabetic nephropathy (DN). However, the regulation of gremlin in podocytes is still rarely reported. This study aimed to investigate the underlying mechanisms by which gremlin mediates the pathogenesis of DN via transforming growth factor-ß (TGF-ß) signaling pathways. MATERIAL AND METHODS Lentiviral and RNAi transfection were performed to increase and decrease gremlin expression in high-glucose conditions. Expression at the mRNA and protein level was detected by RT-qPCR and Western blotting. RESULTS The expression of gremlin was significantly higher in high-glucose (HG, 30mM) than normal-glucose (NG, 5.5 mM) conditions. The gremlin overexpression significantly suppressed the expression of nephrin and synaptopodin. The phosphorylation of canonical TGF-b signaling pathway components, including Smad2/3 and MKK, was increased in the gremlin-overexpressing group. In addition, the expression levels of Bax and cleaved caspase-3 were also higher in the gremlin-overexpressing group. TGF-ß pathway inhibitor (SB505124) significantly inhibited TGF-ß pathway activity and enhanced the expression of nephrin and synaptopodin. CONCLUSIONS These results indicate that gremlin can aggravate podocyte lesions through the TGF-ß signaling pathway, providing a novel therapeutic target for DN.


Asunto(s)
Apoptosis , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Podocitos/citología , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Animales , Apoptosis/efectos de los fármacos , Benzodioxoles/farmacología , Citocinas , Imidazoles/farmacología , Péptidos y Proteínas de Señalización Intercelular/genética , Lentivirus/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Proteínas de Microfilamentos/metabolismo , Podocitos/efectos de los fármacos , Podocitos/metabolismo , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
12.
Bioorg Med Chem ; 25(21): 5917-5928, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28988627

RESUMEN

A series of salicyladimine derivatives were designed, synthesized and evaluated as multi-target-directed ligands for the treatment of Alzheimer's disease (AD). Biological activity results demonstrated that some derivatives possessed significant inhibitory activities against amyloid-ß (Aß) aggregation and human monoamine oxidase B (hMAO-B) as well as remarkable antioxidant effects and low cell toxicity. The optimal compound, 5, exhibited excellent potency for inhibition of self-induced Aß1-42 aggregation (91.3±2.1%, 25µM), inhibition of hMAO-B (IC50, 1.73±0.39µM), antioxidant effects (43.4±2.6µM of IC50 by DPPH method, 0.67±0.06 trolox equivalent by ABTS method), metal chelation and BBB penetration. Furthermore, compound 5 had neuroprotective effects against ROS generation, H2O2-induced apoptosis, 6-OHDA-induced cell injury, and a significant in vitro anti-inflammatory activity. Collectively, these findings highlighted that compound 5 was a potential balanced multifunctional neuroprotective agent for the development of anti-AD drugs.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Diseño de Fármacos , Iminas/farmacología , Inhibidores de la Monoaminooxidasa/farmacología , Salicilatos/farmacología , Péptidos beta-Amiloides/antagonistas & inhibidores , Animales , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Peróxido de Hidrógeno/farmacología , Iminas/síntesis química , Iminas/química , Ligandos , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Simulación del Acoplamiento Molecular , Estructura Molecular , Monoaminooxidasa/metabolismo , Inhibidores de la Monoaminooxidasa/síntesis química , Inhibidores de la Monoaminooxidasa/química , Células PC12 , Fragmentos de Péptidos/antagonistas & inhibidores , Agregado de Proteínas/efectos de los fármacos , Ratas , Salicilatos/síntesis química , Salicilatos/química , Relación Estructura-Actividad
13.
Bioorg Med Chem ; 25(14): 3815-3826, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28549891

RESUMEN

In a continuing effort to develop multitargeted compounds as potential treatment agents against Alzheimer's disease (AD), a series of chromone derivatives were designed, synthesized and evaluated. In vitro assay indicated that most of the target compounds have both MAOs inhibition activities, antioxidant activity and biometal chelating ability. Especially, compound s19 exhibits good inhibitory potency for inhibition of MAOs (IC50 value of 5.12µM for hMAO-A and 0.816µM for hMAO-B), moderate inhibition of Aß aggregation (75.1% at 20µM), metal chelation, control of ROS generation and antioxidant activity (ORAC=3.62). In addition, s19 could reduce PC12 cells death induced by oxidative stress and penetrate the blood-brain barrier (BBB). Taken together, these results suggested that s19 might be a promising multitargeted compound for AD treatment.


Asunto(s)
Cromonas/química , Inhibidores de la Monoaminooxidasa/síntesis química , Monoaminooxidasa/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Animales , Antioxidantes/metabolismo , Apoptosis/efectos de los fármacos , Sitios de Unión , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Cromonas/farmacología , Cromonas/uso terapéutico , Cobre/química , Cobre/metabolismo , Humanos , Peróxido de Hidrógeno/toxicidad , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacología , Inhibidores de la Monoaminooxidasa/uso terapéutico , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Células PC12 , Estructura Terciaria de Proteína , Ratas , Especies Reactivas de Oxígeno/metabolismo , Relación Estructura-Actividad
14.
J Nat Prod ; 80(4): 989-998, 2017 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-28245113

RESUMEN

Three new syncarpic acid-conjugated sesquiterpenoids, tomentodiones E-G (1-3), and six new syncarpic acid-conjugated monoterpenoids, tomentodiones H-M (4-9), were isolated from the leaves of Rhodomyrtus tomentosa. Compounds 1-3 represent the first examples of ß-calacorene-based meroterpenoids. Their structures and absolute configurations were determined by a combination of NMR and ECD spectroscopy and X-ray diffraction analysis. On the basis of ECD data analysis for isolated and synthesized compounds, an empirical rule was proposed to determine the absolute configuration at C-7' of syncarpic acid-conjugated terpenoids. Additionally, a study of the reversal effect of multidrug resistance in doxorubicin-resistant human breast cancer cells showed that the noncytotoxic (+)-4 exerted the strongest potentiation effect of doxorubicin susceptibility, with an enhancement of 16.5-fold at a concentration of 30 µM.


Asunto(s)
Medicamentos Herbarios Chinos/aislamiento & purificación , Monoterpenos/aislamiento & purificación , Myrtaceae/química , Sesquiterpenos/aislamiento & purificación , Terpenos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Resistencia a Antineoplásicos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Humanos , Estructura Molecular , Monoterpenos/química , Monoterpenos/farmacología , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Relación Estructura-Actividad , Terpenos/química , Terpenos/farmacología
15.
Chemistry ; 22(33): 11778-84, 2016 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-27412352

RESUMEN

Nine formyl-phloroglucinolmeroterpenoids (FPMs), namely, eucalrobusones A-I (1-9), were isolated from the leaves of Eucalyptus robusta by tracking the phenolic hydroxyl (1) H NMR peaks. The Snatzke helicity rules for the Cotton effects of twisted benzene rings were applied to elucidate the absolute configurations of the FPMs. These findings, along with NMR spectroscopy, the circular dichroism (CD) exciton chirality method, and CD calculations, allowed complete structures for the FPMs to be assigned. Eucalrobusones A-F (1-6) are novel adducts formed between a formyl-derived carbon atom on the phloroglucinol ring and monoterpene and sesquiterpene components. Eucalrobusones G-I (7-9) are the first examples of FPMs with cubebane part structures connected by an unusual 1-oxaspiro[5.5]undecane subunit. Among these isolates, eucalrobusone C (3) showed significant cytotoxicity against HepG2, MCF-7, and U2OS cancer cell lines, with IC50 values less than 10 µm. Compound 3 significantly blocks cell proliferation in MCF-7 cells and induces MCF-7 cell death through apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Eucalyptus/química , Floroglucinol/química , Hojas de la Planta/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Terpenos/química , Terpenos/farmacología , Dicroismo Circular , Humanos , Células MCF-7 , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Estructura Molecular , Sesquiterpenos/aislamiento & purificación , Terpenos/aislamiento & purificación
16.
Org Biomol Chem ; 14(4): 1231-5, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26676888

RESUMEN

Trichiconlides A (1) and B (2), two novel limonoids, were isolated from the fruits of Trichilia connaroides. Compound 1 is a novel limonoid with a highly rearranged A/B ring system and an intact D ring, which formed an unprecedented 5/6/5/6/5 carbon skeleton. Trichiconlide B (2) possesses a 10-oxatricyclo[3.3.1.(3,8)]decane core and formed a cage-like structure located between rings A and C. Their structures and absolute configurations were elucidated by spectroscopic methods, single crystal X-ray diffraction, the ECD exciton chirality method and TDDFT/ECD calculations. 1 showed a moderate inhibitory effect on nitric oxide (NO) production.


Asunto(s)
Frutas/química , Limoninas/aislamiento & purificación , Meliaceae/química , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Limoninas/química , Limoninas/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Modelos Moleculares , Conformación Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Estereoisomerismo , Relación Estructura-Actividad
18.
Bioorg Med Chem ; 24(18): 4324-4338, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27460699

RESUMEN

A novel series of compounds obtained by fusing the acetylcholinesterase (AChE) inhibitor donepezil and the antioxidant melatonin were designed as multi-target-directed ligands for the treatment of Alzheimer's disease (AD). In vitro assay indicated that most of the target compounds exhibited a significant ability to inhibit acetylcholinesterase (eeAChE and hAChE), butyrylcholinesterase (eqBuChE and hBuChE), and ß-amyloid (Aß) aggregation, and to act as potential antioxidants and biometal chelators. Especially, 4u displayed a good inhibition of AChE (IC50 value of 193nM for eeAChE and 273nM for hAChE), strong inhibition of BuChE (IC50 value of 73nM for eqBuChE and 56nM for hBuChE), moderate inhibition of Aß aggregation (56.3% at 20µM) and good antioxidant activity (3.28trolox equivalent by ORAC assay). Molecular modeling studies in combination with kinetic analysis revealed that 4u was a mixed-type inhibitor, binding simultaneously to catalytic anionic site (CAS) and the peripheral anionic site (PAS) of AChE. In addition, 4u could chelate metal ions, reduce PC12 cells death induced by oxidative stress and penetrate the blood-brain barrier (BBB). Taken together, these results strongly indicated the hybridization approach is an efficient strategy to identify novel scaffolds with desired bioactivities, and further optimization of 4u may be helpful to develop more potent lead compound for AD treatment.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antioxidantes/farmacología , Inhibidores de la Colinesterasa/farmacología , Indanos/farmacología , Indoles/farmacología , Melatonina/análogos & derivados , Melatonina/farmacología , Piperidinas/farmacología , Acetilcolinesterasa/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Animales , Antioxidantes/síntesis química , Antioxidantes/toxicidad , Barrera Hematoencefálica/metabolismo , Butirilcolinesterasa/metabolismo , Dominio Catalítico , Línea Celular Tumoral , Quelantes/síntesis química , Quelantes/farmacología , Quelantes/toxicidad , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/toxicidad , Donepezilo , Electrophorus , Caballos , Humanos , Indanos/síntesis química , Indanos/toxicidad , Indoles/síntesis química , Indoles/toxicidad , Hierro/química , Cinética , Melatonina/síntesis química , Melatonina/toxicidad , Simulación del Acoplamiento Molecular , Fragmentos de Péptidos/antagonistas & inhibidores , Piperidinas/síntesis química , Piperidinas/toxicidad , Multimerización de Proteína , Ratas , Zinc/química
19.
J Nat Prod ; 79(5): 1231-40, 2016 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-27148858

RESUMEN

The isolation of the new polycyclic polyprenylated acylphloroglucinols uraliones A-K (1-11) together with five known analogues (12-16) from a whole Hypericum uralum plant was reported. The structures of these compounds were established through spectroscopic methods, and a single-crystal X-ray diffraction analysis was used to confirm the absolute configuration of 1. The protective effects of the isolates against corticosterone-induced PC12 cell injury were assessed. Except for compound 9, all tested compounds exhibited significant protective effects against induced injury in PC12 cells. Uralodin A (14), orally administered in doses of 13 and 26 mg/kg, exhibited antidepressant-like activity in the tail suspension and forced-swimming tests in mice.


Asunto(s)
Antidepresivos , Medicamentos Herbarios Chinos , Hypericum/química , Fármacos Neuroprotectores , Floroglucinol , Administración Oral , Animales , Antidepresivos/química , Antidepresivos/aislamiento & purificación , Antidepresivos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Humanos , Ratones , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Resonancia Magnética Nuclear Biomolecular , Células PC12 , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/aislamiento & purificación , Floroglucinol/farmacología , Ratas
20.
J Nat Prod ; 79(1): 196-203, 2016 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-26741483

RESUMEN

During an ongoing exploration of potential anti-inflammatory agents from medicinal plants, eight new arylalkenyl α,ß-unsaturated δ-lactones, cryptoconcatones A-H (1-8), and two unusual arylalkenyl α,ß-unsaturated γ-lactones, cryptoconcatones I and J (9 and 10), were identified from the leaves and twigs of Cryptocarya concinna. The structures of these compounds were established based on spectroscopic data (MS, 1D/2D NMR), and their absolute configurations were determined with Riguera's method, the modified Mosher's method, chemical derivatization, and the Snatzke chirality rule. Compounds 4-6 and 8-10 showed inhibitory activity toward nitric oxide (NO) production in lipopolysaccharide-induced RAW 264.7 macrophages, particularly compounds 4 and 8-10, with IC50 values of 3.2, 4.2, 3.4, and 7.5 µM, respectively.


Asunto(s)
Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Cryptocarya/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Lactonas/aislamiento & purificación , Lactonas/farmacología , Animales , Antiinflamatorios/química , Medicamentos Herbarios Chinos/química , Lactonas/química , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Componentes Aéreos de las Plantas/química , Estereoisomerismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA