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1.
Cell ; 183(6): 1682-1698.e24, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33232692

RESUMO

In order to analyze how a signal transduction network converts cellular inputs into cellular outputs, ideally one would measure the dynamics of many signals within the network simultaneously. We found that, by fusing a fluorescent reporter to a pair of self-assembling peptides, it could be stably clustered within cells at random points, distant enough to be resolved by a microscope but close enough to spatially sample the relevant biology. Because such clusters, which we call signaling reporter islands (SiRIs), can be modularly designed, they permit a set of fluorescent reporters to be efficiently adapted for simultaneous measurement of multiple nodes of a signal transduction network within single cells. We created SiRIs for indicators of second messengers and kinases and used them, in hippocampal neurons in culture and intact brain slices, to discover relationships between the speed of calcium signaling, and the amplitude of PKA signaling, upon receiving a cAMP-driving stimulus.


Assuntos
Corantes Fluorescentes/metabolismo , Genes Reporter , Imagem Óptica , Transdução de Sinais , Animais , Cálcio/metabolismo , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Hipocampo/metabolismo , Humanos , Camundongos , Neurônios/metabolismo , Peptídeos/metabolismo , Proteínas/metabolismo , Células Piramidais/metabolismo
2.
BMC Genomics ; 25(1): 613, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890561

RESUMO

BACKGROUND: The domain of unknown function 247 (DUF247) proteins is involved in plant development and stress response. Rice is an important worldwide cereal crop, although an increasing number of DUF proteins have been identified, the understanding of DUF proteins is still very limited in rice. RESULTS: In this study, we identified 69 genes that encode DUF247 proteins in the rice (Oryza sativa) genome by homology searches and domain prediction. All the OsDUF247 proteins were classified into four major groups (I, II, III and IV) by phylogenetic analysis. Remarkably, OsDUF247 genes clustered on the chromosomes solely show close phylogenetic relationships, suggesting that gene duplications have driven the expansion of the DUF247 gene family in the rice genome. Tissue profile analysis showed that most DUF247 genes expressed at constitutive levels in seedlings, roots, stems, and leaves, except for seven genes (LOC_Os01g21670, LOC_Os03g19700, LOC_Os05g04060, LOC_Os08g26820, LOC_Os08g26840, LOC_Os08g26850 and LOC_Os09g13410) in panicles. These seven genes were induced by various abiotic stress, including cold, drought, heat, hormone treatment, and especially salt, as demonstrated by further experimental analysis. DUF247 proteins contain transmembrane domains located on the membrane, suggesting their significant roles in rice development and adaptation to the environment. CONCLUSIONS: These findings lay the foundation for functional characterizations of DUF247 genes to unravel their exact role in rice cultivars.


Assuntos
Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Oryza , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Oryza/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Cromossomos de Plantas/genética , Perfilação da Expressão Gênica , Genes de Plantas , Duplicação Gênica
3.
Environ Sci Technol ; 58(22): 9731-9740, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38781307

RESUMO

Carbonaceous aerosols play an important role in radiative forcing in the remote and climate-sensitive Tibetan Plateau (TP). However, the sources of carbonaceous aerosols to the TP remain poorly defined, in part due to the lack of regionally relevant data about the sources of carbonaceous aerosols. To address this knowledge gap, we present the first comprehensive analysis of the δ13C signatures of carbonaceous aerosol endmembers local to the TP, encompassing total carbon, water-insoluble particle carbon, and elemental carbon originating from fossil fuel combustion, biomass combustion, and topsoil. The δ13C signatures of these local carbonaceous endmembers differ from components collected in other regions of the world. For instance, fossil fuel-derived aerosols from the TP were 13C-depleted relative to fossil fuel-derived aerosols reported in other regions, while biomass fuel-derived aerosols from the TP were 13C-enriched relative to biomass fuel-derived aerosols reported in other regions. The δ13C values of fine-particle topsoil in the TP were related to regional variations in vegetation type. These findings enhance our understanding of the unique features of carbonaceous aerosols in the TP and aid in accurate source apportionment and environmental assessments of carbonaceous aerosols in this climate-sensitive region.


Assuntos
Aerossóis , Isótopos de Carbono , Tibet , Carbono , Monitoramento Ambiental
4.
Environ Monit Assess ; 195(12): 1540, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38012471

RESUMO

Remote region is normally considered a receptor of long-range transported pollutants. Monitoring stations are important platforms for investigating the atmospheric environment of remote regions. However, the potential contribution of very local sources around these stations may produce important influences on its atmospheric environment, which is still barely studied. In this study, major ions of precipitation were investigated simultaneously at a typical remote station (Nam Co station) and other sites nearby on the Tibetan Plateau (TP) - the so-called "The Third Pole" in the world. The results showed that despite low values compared to those of other remote regions, the concentrations of major ions in precipitation of Nam Co station (e.g., Ca2+: 32.71 µeq/L; [Formula: see text]: 1.73 µeq/L) were significantly higher than those at a site around 2.2 Km away (Ca2+: 11.47 µeq/L; [Formula: see text]: 0.64 µeq/L). This provides direct evidence that atmospheric environment at Nam Co station is significantly influenced by mineral dust and pollutants emitted from surface soil and anthropogenic pollutants of the station itself. Therefore, numbers of other related data reported on the station are influenced. For example, the aerosol concentration and some anthropogenic pollutants reported on Nam Co station should be overestimated. Meanwhile, it is suggested that it is cautious in selecting sites for monitoring the atmospheric environment at the remote station to reduce the potential influence from local sources.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Tibet , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Íons
5.
Angew Chem Int Ed Engl ; 62(23): e202303670, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36996038

RESUMO

Axially chiral biaryls widely exist in natural products and pharmaceuticals and are used as chiral ligands and catalysts in asymmetric synthesis. Compared to the well-established axially chiral 6-membered biaryl skeletons, examples of 5-membered biaryls have been quite scarce, and mono-substituted 3-arylpyrrole atropisomers have not been reported. Here, we disclose a copper-catalyzed atroposelective diyne cyclization for the construction of a range of axially chiral arylpyrrole biaryls in good to excellent yields with generally excellent enantioselectivities via oxidation and X-H insertion of vinyl cations. Importantly, this protocol not only represents the first synthesis of mono-substituted 3-arylpyrrole atropisomers, but also constitutes the first example of atroposelective diyne cyclization and the first atropisomer construction via vinyl cations. Theoretical calculations further support the mechanism of vinyl cation-involved cyclization and elucidate the origin of enantioselectivity.

6.
J Pharmacol Exp Ther ; 377(3): 316-325, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33722881

RESUMO

Ca2+/calmodulin-dependent protein kinase II (CaMKII) is upregulated in congestive heart failure (CHF), contributing to electrical, structural, and functional remodeling. CaMKII inhibition is known to improve CHF, but its direct cardiac effects in CHF remain unclear. We hypothesized that CaMKII inhibition improves cardiomyocyte function, [Ca2+]i regulation, and ß-adrenergic reserve, thus improving advanced CHF. In a 16-week study, we compared plasma neurohormonal levels and left ventricular (LV)- and myocyte-functional and calcium transient ([Ca2+]iT) responses in male Sprague-Dawley rats (10/group) with CHF induced by isoproterenol (170 mg/kg sq for 2 days). In rats with CHF, we studied the effects of the CaMKII inhibitor KN-93 or its inactive analog KN-92 (n = 4) (70 µg/kg per day, mini-pump) for 4 weeks. Compared with controls, isoproterenol-treated rats had severe CHF with 5-fold-increased plasma norepinephrine and about 50% decreases in ejection fraction (EF) and LV contractility [slope of LV end-systolic pressure-LV end-systolic volume relation (EES)] but increased time constant of LV relaxation (τ). They also showed significantly reduced myocyte contraction [maximum rate of myocyte shortening (dL/dtmax)], relaxation (dL/dtmax), and [Ca2+]iT Isoproterenol superfusion caused significantly fewer increases in dL/dtmax and [Ca2+]iT KN-93 treatment prevented plasma norepinephrine elevation, with increased basal and acute isoproterenol-stimulated increases in EF and EES and decreased τ in CHF. KN-93 treatment preserved normal myocyte contraction, relaxation, [Ca2+]iT, and ß-adrenergic reserve, whereas KN-92 treatment failed to improve LV and myocyte function, and plasma norepinephrine remained high in CHF. Thus, chronic CaMKII inhibition prevented CHF-induced activation of the sympathetic nervous system, restoring normal LV and cardiomyocyte basal and ß-adrenergic-stimulated contraction, relaxation, and [Ca2+]iT, thereby playing a rescue role in advanced CHF. SIGNIFICANCE STATEMENT: We investigated the therapeutic efficacy of late initiation of chronic Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibition on progression of advanced congestive heart failure (CHF). Chronic CaMKII inhibition prevented CHF-induced activation of the sympathetic nervous system and restored normal intrinsic cardiomyocyte basal and ß-adrenergic receptor-stimulated relaxation, contraction, and [Ca2+]i regulation, leading to reversal of CHF progression. These data provide new evidence that CaMKII inhibition is able and sufficient to rescue a failing heart, and thus cardiac CaMKII inhibition is a promising target for improving CHF treatment.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Animais , Insuficiência Cardíaca , Ratos , Ratos Sprague-Dawley
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(1): 12-16, 2020 Jan.
Artigo em Zh | MEDLINE | ID: mdl-31948518

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of C-reactive protein (CRP)-guided antibiotic treatment strategy for neonates with suspected early-onset sepsis (EOS). METHODS: A total of 428 neonates, with a gestational age of >35 weeks, who were admitted to the Children's Hospital of Chongqing Medical University from February to July, 2019 and were suspected of EOS were enrolled as the observation group. The effect of antibiotic treatment was prospectively observed, and if clinical symptoms were improved and CRP was <10 mg/L in two consecutive tests, discontinuation of antibiotics was considered. A total of 328 neonates (gestational age of >35 weeks) who were admitted to this hospital from February to July, 2018 and were suspected of EOS were enrolled as the control group, and the use of antibiotics was analyzed retrospectively. The two groups were compared in terms of duration of antibiotic treatment, length of hospital stay, incidence rate of repeated infection and clinical outcome. RESULTS: Compared with the control group, the observation group had significantly shorter duration of antibiotic treatment and length of hospital stay (P<0.05). There were no significant differences in the incidence rate of repeated infection and clinical outcome between the two groups (P>0.05). CONCLUSIONS: For neonates with a gestational age of >35 weeks and a suspected diagnosis of EOS, CRP-guided antibiotic treatment strategy can shorten duration of antibiotic treatment and length of hospital stay and does not increase the incidence rate of repeated infection. Therefore, it holds promise for clinical application.


Assuntos
Antibacterianos/uso terapêutico , Sepse , Proteína C-Reativa , Idade Gestacional , Humanos , Recém-Nascido , Estudos Retrospectivos , Sepse/tratamento farmacológico
8.
Chem Pharm Bull (Tokyo) ; 66(5): 469-482, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710044

RESUMO

Madagascar's rain forests and tropical dry forests are home to numerous endemic plant species and the island is considered a biodiversity hotspot. About 80% of the Madagascan (Malagasy) population relies on traditional medicines that have been proven to contain a variety of biologically active compounds. In the search for bioactive compounds from Madagascan biodiversity, we accessed and collected most of the literature dealing with the isolation, structure elucidation, and biological activities of organic small molecules originating from Madagascan plants and marine organisms. Since we published the first review of this work in 2009 (Curr. Med. Chem., 17, 2010, Hou and Harinantenaina), the present paper covers the isolation, structures, and bioactivity of 182 new secondary metabolites isolated from Malagasy higher plants and marine organisms in the last seven years (2009-2017).


Assuntos
Organismos Aquáticos/química , Produtos Biológicos/isolamento & purificação , Plantas/química , Bibliotecas de Moléculas Pequenas/isolamento & purificação , Biodiversidade , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Madagáscar , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo
9.
Anal Bioanal Chem ; 408(19): 5261-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27235159

RESUMO

A method to detect small molecules with a molecularly imprinted polymer/quantum dot (MIP-QD) chip using a home-built optical fluidic system was first proposed in this study. Ractopamine (RAC) was used as the model molecule to demonstrate its feasibility. The sensing of the target molecule is based on the quenching amount of the quantum dots. The method is facile, cost-saving, easy for miniaturization and avoids the cumbersome steps that are needed to get the fluorescent quenching curve using a spectrofluorometer. Most importantly, more details and accurate response time can be obtained by use of this method. The experimental results show that the prepared chips with low cost are highly selective and the home-built detection system allows the fast binding kinetics. The recorded quenching process was used to study the kinetic uptake of RAC onto the MIP-QD chip and the specificity towards RAC. The system can further be utilized to study the effect of the solvent, pH and temperature on the selectivity of the prepared MIP. The methodology could be extended to other similar studies with different molecules. Graphical abstract Schematic illustration of the molecularly imprinted polymer/quantum dot chip capturing the target molecule.

10.
Anal Chem ; 87(10): 5286-93, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25902043

RESUMO

We presented a decoding method of quantum dots encoded microbeads with its fluorescence spectra using line scan hyperspectral fluorescence imaging (HFI) method. A HFI method was developed to attain both the spectra of fluorescence signal and the spatial information of the encoded microbeads. A decoding scheme was adopted to decode the spectra of multicolor microbeads acquired by the HFI system. Comparison experiments between the HFI system and the flow cytometer were conducted. The results showed that the HFI system has higher spectrum resolution; thus, more channels in spectral dimension can be used. The HFI system detection and decoding experiment with the single-stranded DNA (ssDNA) immobilized multicolor beads was done, and the result showed the efficiency of the HFI system. Surface modification of the microbeads by use of the polydopamine was characterized by the scanning electron microscopy and ssDNA immobilization was characterized by the laser confocal microscope. These results indicate that the designed HFI system can be applied to practical biological and medical applications.


Assuntos
DNA de Cadeia Simples/análise , Ácidos Nucleicos Imobilizados/análise , Microesferas , Imagem Óptica/instrumentação , Pontos Quânticos/química , Sequência de Bases , Desenho de Equipamento , Indóis/química , Microscopia Confocal , Polímeros/química , Poliestirenos/química , Polivinil/química
11.
J Nat Prod ; 78(6): 1330-8, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26042470

RESUMO

Antimalarial bioassay-guided fractionation of an EtOH extract of the root wood of Cryptocarya rigidifolia (Lauraceae) led to the isolation of the five new 5,6-dihydro-α-pyrones cryptorigidifoliols A-E (1-5) and the six bicyclic tetrahydro-α-pyrone derivatives cryptorigidifoliols F-K (6-11). The structure elucidations of all compounds were made on the basis of the interpretation of spectroscopic data and chemical derivatization, and the relative and absolute configurations were determined by NOESY, electronic circular dichroism (ECD), and (1)H NMR analysis of α-methoxyphenylacetyl (MPA) derivatives. The bicyclic tetrahydro-α-pyrone derivatives were identified as products of acid-catalyzed intramolecular Michael addition of the 5,6-dihydro-α-pyrones in the presence of silica gel. A structure-activity relationship study suggested that the presence of an α,ß-unsaturated carbonyl moiety is not essential for potent antimalarial activity.


Assuntos
Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Cryptocarya/química , Pironas/isolamento & purificação , Pironas/farmacologia , Antimaláricos/química , Dicroísmo Circular , Cristalografia por Raios X , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pironas/química , Relação Estrutura-Atividade
12.
J Nat Prod ; 78(7): 1543-7, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26091020

RESUMO

The two new lignans 3α-O-(ß-D-glucopyranosyl)desoxypodophyllotoxin (1) and 4-O-(ß-D-glucopyranosyl)dehydropodophyllotoxin (2) were isolated from Cleistanthus boivinianus, together with the known lignans deoxypicropodophyllotoxin (3), (±)-ß-apopicropodophyllin (4), (-)-desoxypodophyllotoxin (5), (-)-yatein (6), and ß-peltatin-5-O-ß-D-glucopyranoside (7). The structures of all compounds were characterized by spectroscopic techniques. Compounds 1, 4, and 5 showed potent antiproliferative activities against the A2780 ovarian cancer cell line, with IC50 values of 33.0 ± 3.6, 63.1 ± 6.7, and 230 ± 1 nM, respectively. Compounds 2 and 7 showed only modest A2780 activities, with IC50 values of 2.1 ± 0.3 and 4.9 ± 0.1 µM, respectively, while compounds 3 and 6 had IC50 values of >10 µM. Compound 1 also had potent antiproliferative activity against the HCT-116 human colon carcinoma cell line, with an IC50 value of 20.5 nM, and compound 4 exhibited modest antiproliferative activity against the A2058 human caucasian metastatic melanoma and MES-SA human uterine sarcoma cell lines, with IC50 values of 4.6 and 4.0 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Lignanas/isolamento & purificação , Lignanas/farmacologia , Malpighiaceae/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , Antineoplásicos Fitogênicos/química , Proliferação de Células/efeitos dos fármacos , Dioxóis/química , Ensaios de Seleção de Medicamentos Antitumorais , Florestas , Células HCT116 , Humanos , Concentração Inibidora 50 , Lignanas/química , Madagáscar , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Estereoisomerismo
13.
Tetrahedron Lett ; 56(23): 3630-3632, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-26034338

RESUMO

Bioassay-directed fractionation of an antiproliferative ethanol extract of the roots of Ocotea macrocarpa (Lauraceae) afforded the new butanolide macrocarpolide A (1), and the two new secobutanolides macrocarpolides B (2) and C (3), together with the known butanolides linderanolide B (4) and isolinderanolide (5). The structure elucidation of all compounds was carried out based on NMR and mass spectroscopic data analyses. The absolute configurations of all compounds isolated were determined by comparison of their optical rotation values with those found in literature. Compounds 1-5 showed good antiproliferative activities against the A2780 ovarian cell line, with IC50 values of 2.57 ± 0.12 (1), 1.98 ± 0.23 (2), 1.67 ± 0.05 (3), 2.43 ± 0.41 (4), and 1.65 ± 0.44 µM (5), respectively.

14.
Medicine (Baltimore) ; 103(14): e37512, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579077

RESUMO

ShenGui capsule (SGC), as a herbal compound, has significant effects on the treatment of heart failure (HF), but its mechanism of action is unclear. In this study, we aimed to explore the potential pharmacological targets and mechanisms of SGC in the treatment of HF using network pharmacology and molecular docking approaches. Potential active ingredients of SGC were obtained from the traditional Chinese medicine systems pharmacology database and analysis platform database and screened by pharmacokinetic parameters. Target genes of HF were identified by comparing the toxicogenomics database, GeneCards, and DisGeNET databases. Protein interaction networks and gene-disorder-target networks were constructed using Cytoscape for visual analysis. Gene ontology and Kyoto Encyclopedia of Genes and Genomes were also performed to identify protein functional annotations and potential target signaling pathways through the DAVID database. CB-DOCK was used for molecular docking to explore the role of IL-1ß with SGC compounds. Sixteen active ingredients in SGC were screened from the traditional Chinese medicine systems pharmacology database and analysis platform, of which 36 target genes intersected with HF target genes. Protein-protein interactions suggested that each target gene was closely related, and interleukin-1ß (IL-1ß) was identified as Hub gene. The network pharmacology analysis suggested that these active ingredients were well correlated with HF. Kyoto Encyclopedia of Genes and Genomes enrichment analysis suggested that target genes were highly enriched in pathways such as inflammation. Molecular docking results showed that IL-1ß binds tightly to SGC active components. This experiment provides an important research basis for the mechanism of action of SGC in the treatment of HF. In this study, the active compounds of SGC were found to bind IL-1ß for the treatment of heart failure.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Humanos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Insuficiência Cardíaca/tratamento farmacológico , Mapas de Interação de Proteínas , Bases de Dados Factuais , Interleucina-1beta , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
15.
Sci Total Environ ; 922: 171321, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38423306

RESUMO

Carbonaceous particles play a crucial role in atmospheric radiative forcing. However, our understanding of the behavior and sources of carbonaceous particles in remote regions remains limited. The Tibetan Plateau (TP) is a typical remote region that receives long-range transport of carbonaceous particles from severely polluted areas such as South Asia. Based on carbon isotopic compositions (Δ14C/δ13C) of water-insoluble particulate carbon (IPC) in total suspended particle (TSP), PM2.5, and precipitation samples collected during 2020-22 at the Nam Co Station, a remote site in the inner TP, the following results were achieved: First, fossil fuel contributions (ffossil) to IPC in TSP samples (28.60 ± 9.52 %) were higher than that of precipitation samples (23.11 ± 8.60 %), and it is estimated that the scavenging ratio of IPC from non-fossil fuel sources was around 2 times that from fossil fuel combustion during the monsoon season. The ffossil of IPC in both TSP and PM2.5 samples peaked during the monsoon season. Because heavy precipitation during the monsoon season scavenges large amounts of long-range transported carbonaceous particles, the contribution of local emissions from the TP largely outweighs that from South Asia during this season. The results of the IPC source apportionment based on Δ14C and δ13C in PM2.5 samples showed that the highest contribution of liquid fossil fuel combustion also occurred in the monsoon season, reflecting increased human activities (e.g., tourism) on the TP during this period. The results of this study highlight the longer lifetime of fossil fuel-sourced IPC in the atmosphere than that of non-fossil fuel sources in the inner TP and the importance of local emissions from the TP during the monsoon season. The findings provide new knowledge for model improvement and mitigation of carbonaceous particles.

16.
Cell Physiol Biochem ; 32(6): 1631-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24335437

RESUMO

BACKGROUND: The beta 3-adrenoceptor (ß3-AR) is closely associated with energy metabolism. This study aimed to explore the role of ß3-AR in energy remodeling in a rabbit model of pacing-induced atrial fibrillation (AF). METHODS: Rabbits with a sham-operation or pacing-induced AF were used for this study, and the latter group was further divided into three subgroups: 1) the pacing group, 2) the ß3-AR agonist (BRL37344)-treated group, and 3) the ß3-AR antagonist (SR59230A)-treated group. Atrial electrogram morphology and surface ECG were used to monitor the induction of AF and atrial effective refractory period (AERP). RT-PCR and western blot (WB) were used to show alterations in ß3-AR and metabolic-related protein. RESULTS: RT-PCR and WB results showed that ß3-AR was significantly upregulated in the pacing group, and that it corresponded with high AF inducibility and significantly decreased AERP200 and ATP production in this group. Inhibition of ß3-AR decreased the AF induction rate, reversed AERP200 reduction, and restored ATP levels in the AF rabbits. Further activation of ß3-AR using agonist BRL37344 exacerbated AF-induced metabolic disruption. Periodic acid Schiff (PAS) and Oil Red O staining showed ß3-AR-dependent glycogen and lipid droplet accumulation in cardiac myocytes with AF. Glucose transporter-4 (GLUT-4) and CD36, key transporters of glucose and fatty acids, were downregulated in the pacing group. Expression of carnitine-palmitoyltransferase I (CPT-1), a key regulator in fatty acid metabolism, was also significantly downregulated in the pacing group. Reduced glucose transportation and fatty acid oxidation could be restored by inhibition of ß3-AR. Furthermore, key regulators of metabolism, peroxisome proliferator-activated receptor-α (PPARα) and PPAR co-activator (PGC-1α) can be regulated by pharmacological intervention of the ß3-AR. CONCLUSIONS: ß3-AR is involved in metabolic protein remodeling in AF. PPARα/PGC-1α signaling pathway might be the relevant down-stream molecular machinery in response to AF-induced activation of ß3-AR. ß3-AR might be a novel target in AF treatment.


Assuntos
Fibrilação Atrial/patologia , Receptores Adrenérgicos beta 3/metabolismo , Trifosfato de Adenosina/metabolismo , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Antagonistas de Receptores Adrenérgicos beta 3/farmacologia , Animais , Fibrilação Atrial/metabolismo , Antígenos CD36/genética , Antígenos CD36/metabolismo , Estimulação Cardíaca Artificial , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Eletrocardiografia , Ácidos Graxos/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Propanolaminas/farmacologia , Coelhos , Receptores Adrenérgicos beta 3/química , Receptores Adrenérgicos beta 3/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
17.
Bioorg Med Chem ; 21(24): 7591-4, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24239390

RESUMO

Bioassay-directed fractionation of the leaf and root extracts of the antiproliferative Madagascar plant Stuhlmannia moavi afforded 6-acetyl-5,8-dihydroxy-2-methoxy-7-methyl-1,4-naphthoquinone (stuhlmoavin, 1) as the most active compound, with an IC50 value of 8.1 µM against the A2780 human ovarian cancer cell line, as well as the known homoisoflavonoid bonducellin (2) and the stilbenoids 3,4,5'-trihydroxy-3'-methoxy-trans-stilbene (3), piceatannol (4), resveratrol (5), rhapontigenin (6), and isorhapontigenin (7). The structure elucidation of all compounds was based on NMR and mass spectroscopic data, and the structure of 1 was confirmed by a single crystal X-ray analysis. Compounds 2-5 showed weak A2780 activities, with IC50 values of 10.6, 54.0, 41.0, and 74.0 µM, respectively. Compounds 1-3 also showed weak antimalarial activity against Plasmodium falciparum with IC50 values of 23, 26, and 27 µM, respectively.


Assuntos
Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Caesalpinia/química , Plasmodium falciparum/efeitos dos fármacos , Árvores/química , Antimaláricos/química , Antimaláricos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Madagáscar , Modelos Moleculares , Estrutura Molecular , Testes de Sensibilidade Parasitária , Folhas de Planta/química , Raízes de Plantas/química , Relação Estrutura-Atividade
18.
Magn Reson Chem ; 51(9): 574-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23754698

RESUMO

Antiproliferative bioassay-guided fractionation of the ethanol extract of the stems of Anisocycla grandidieri led to the isolation of the known alkaloids stebisimine (1), (+)-1,2-dehydrotelobine (2), (+)-2'-norcocsuline (3) and puetogaline B (4). Herein, we report the full NMR assignments of all compounds and the X-ray crystallography of single crystals of compounds 1 and 3. Compounds 2 and 3 showed moderate antiproliferative activity against the A2780 human ovarian cancer cell line with IC50 values of 4.1 ± 0.3 and 2.7 ± 0.3 µM, respectively, and they also displayed selective activity toward the H460 (large cell lung cancer), MCF-7 (breast ductal carcinoma), and UACC-257 (melanoma) cell lines.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Menispermaceae/química , Árvores/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Madagáscar , Espectroscopia de Ressonância Magnética/normas , Modelos Moleculares , Estrutura Molecular , Caules de Planta/química , Padrões de Referência , Relação Estrutura-Atividade
19.
Oncol Rep ; 50(3)2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37477123

RESUMO

Subsequently to the publication of the above paper, an interested reader drew to the authors' attention that a pair of the data panels showing the results of Transwell invasion assays (specifically, the 'C4­2 / shCON' and the PC­3 / CON panels) featured in Fig. 3F on p. 927 contained overlapping sections, such that data that were intended to show the results from differently performed experiments appeared to have been derived from the same original source. The authors were able to re­examine their original data files, and realized that this figure had been inadverently assembled incorrectly. The revised version of Fig. 3, containing the correct representative image of the PC­3shCON group, is shown on the next page. The authors also noted that the statistics in Fig. 3G remained correct, and did not require correction on account of the error made in assembling this figure. Similarly, note that the correction made to this figure does not affect the overall conclusions reported in the paper. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish this Corrigendum, and all the authors agree with its publication. They also apologize to the readership for any inconvenience caused. [Oncology Reports 45: 921­932, 2021; DOI: 10.3892/or.2021.7920].

20.
Carbohydr Polym ; 310: 120716, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36925243

RESUMO

Isomalto/malto-polysaccharides (IMMPs) derived from malto-oligosaccharides such as maltoheptaose (G7) are elongated non-branched gluco-oligosaccharides produced by 4,6-α-glucanotransferase (GtfB). However, G7 is expensive and cumbersome to produce commercially. In this study, a cost-effective enzymatic process for IMMPs synthesis is developed that utilizes the combined action of cyclodextrinase from Palaeococcus pacificus (PpCD) and GtfB-ΔN from Limosilactobacillus reuteri 121 to convert ß-cyclodextrin into IMMPs with a maximum yield (16.19 %, w/w). The purified IMMPs synthesized by simultaneous or sequential treatments, designated as IMMP-Sim and IMMP-Seq, possess relatively high contents of α-(1 â†’ 6) glucosidic linkages. By controlling the release of G7 and smaller malto-oligosaccharides by PpCD, IMMP-Seq was obtained of DP varying from 12.9 to 29.5. Enzymatic fingerprinting revealed different linkage-type distribution of α-(1 â†’ 6) linked segments with α-(1 â†’ 4) segments embedded at the reducing end and middle part. The proportion of α-(1 â†’ 6) segments containing the non-reducing end was 56.76 % for IMMP-Sim but 28.98 % for IMMP-Seq. Addition of G3 or G4 as specific acceptors resulted in IMMPs exhibiting low polydispersity. This procedure can be applied as a novel bioprocess that does not require costy high-purity malto-oligosaccharides and with control of the average DP of IMMPs by adjusting the substrate composition.


Assuntos
Polissacarídeos , beta-Ciclodextrinas , Análise Custo-Benefício , Polissacarídeos/química , Oligossacarídeos/química
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