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1.
J Asian Nat Prod Res ; 21(6): 573-578, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30612465

RESUMO

A new brominated polyacetylene xestonariene J (1), bearing a rare 2,4-dibromo-1-ene-3-yne terminal in the molecule, along with two known related analogues (2 and 3), was obtained from Chinese marine sponge Xestospongia testudinaria. Its structure was determined on the basis of detailed spectroscopic analysis and comparison with literature data.


Assuntos
Hidrocarbonetos Bromados/química , Polienos/química , Poli-Inos/química , Poríferos/química , Animais , China , Estrutura Molecular
2.
Chem Asian J ; 14(6): 770-774, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30536637

RESUMO

In this work, we aim to develop cancer cell-targeting AIE dots based on a polyyne-bridged red-emissive AIEgen, 2TPE-4E, through the combination of metabolic engineering and bio-orthogonal reactions. Azide groups on a tumor were efficiently produced by intravenous injection of Ac4ManNAz and glycol-metabolic engineering. These bio-orthogonal azide groups could facilitate the specific targeting of DBCO-AIE dots to the tumor cells undergoing metal-free click reaction in vivo. The efficiency of this targeting strategy could be further improved with the development of new bio-orthogonal chemical groups with higher reactivity and a large amount of AIEgens could be delivered to the tumor for diagnosis.


Assuntos
Engenharia Metabólica , Poli-Inos/química , Animais , Azidas/química , Química Click , Feminino , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Hexosaminas/química , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Neoplasias/diagnóstico , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Pontos Quânticos/química , Espectrometria de Fluorescência , Estilbenos/química , Transplante Heterólogo
3.
J Nat Prod ; 81(11): 2419-2428, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30362739

RESUMO

The total syntheses of all stereoisomers of notoincisol A, a recently isolated natural product with potential anti-inflammatory activity, are reported. The asymmetric synthesis was conducted employing a lipase-mediated kinetic resolution, which enables easy access to all required chiral building blocks with the aim of establishing the absolute configuration of the naturally occurring isomer. This was achieved by comparison of optical properties of the isolated compound with the synthetic derivatives obtained. Moreover, an assessment of the biological activity on PPARγ (peroxisome proliferator-activated receptor gamma) as a prominent receptor related to inflammation is reported. Only the natural isomer was found to activate the PPARγ receptor, and this phenomenon could be explained based on molecular docking studies. In addition, the pharmacological profiles of the isomers were determined using the GABAA (gamma-aminobutyric acid A) ion channel receptor as a representative target for allosteric modulation related to diverse CNS activities. These compounds were found to be weak allosteric modulators of the α1ß3 and α1ß2γ2 receptor subtypes.


Assuntos
Produtos Biológicos/farmacologia , Poli-Inos/farmacologia , Regulação Alostérica , Produtos Biológicos/química , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , PPAR gama/metabolismo , Poli-Inos/química , Estereoisomerismo
4.
Talanta ; 188: 27-34, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029375

RESUMO

MicroRNAs (miRNAs) have emerged as novel biomarkers for human early-phase cancer diagnosis and disease prevention recently. Herein, we reported a novel miRNA-215 targeting biosensor, which was based on single polydiacetylene (PDA) microtube waveguide system integrated with sandwich-type hybridization design and condensing enrichment effect. The target miRNA could be captured by oligonucleotides conjugated on the surface of PDA microtube and Au nanorod (AuNR) respectively, resulting in the out-coupled fluorescence of PDA microtube quenching. In this strategy, the formation of a sandwich structure, as a result of co-hybridization of the target miRNA, enabled simplified preparation process, enhanced reaction efficiency, and increased recyclability and stability of the platform. Based on condensing enrichment effect, the co-hybridization reaction could be enriched on the surface of microtube and the proposed platform could easily achieve highly sensitive detection of miRNA-215 in one step. Remarkably, this platform could be directly applied to discriminate the miRNA-215 expression levels in clinical gastric cancerous, paracancerous and normal tissues samples. This assay offers a simple and convenient method for miRNA quantification in clinical samples, even with the potential for invasive, portable equipment for early clinical diagnosis of diseases.


Assuntos
Técnicas Biossensoriais/métodos , MicroRNAs/análise , Polímeros/química , Poli-Inos/química , Neoplasias Gástricas/diagnóstico , Sequência de Bases , Técnicas Biossensoriais/instrumentação , Sondas de DNA/genética , Fluorescência , Ouro/química , Humanos , Limite de Detecção , Microscopia de Fluorescência , Nanotubos/química , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/genética , Polímero Poliacetilênico , Neoplasias Gástricas/genética
5.
Molecules ; 23(7)2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-30018233

RESUMO

Phytochemical investigation of the apolar extract obtained from aerial parts of the Iranian endemic plant Echinophora platyloba DC (Apiaceae) resulted in the characterization of the polyacetylene fraction of this plant. This resulted to be composed of the known echinophorins A and B, embedding the very rare α-pyrone terminal, and of the new echinophorin D (3), including also three conjugated triple bonds. The chemical structures of these compounds were secured by detailed inspection of MS and 1D/2D NMR spectra. The isolated polyacteylenes were evaluated for their modulation of six thermo-TRP channels and they revealed a selective activity on TRPA1, an ion channel involved in the mediation of neuropathic and inflammatory pain. This is the first report on the activity of plant polyacetylenes on transient receptor potential (TRP) channels.


Assuntos
Apiaceae/química , Poli-Inos/química , Poli-Inos/farmacologia , Canal de Cátion TRPA1/antagonistas & inibidores , Células HEK293 , Humanos , Irã (Geográfico) , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Canal de Cátion TRPA1/metabolismo
6.
Nat Chem ; 10(8): 838-844, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30030536

RESUMO

Polyacenes are organic compounds that have multiple, fused, aromatic rings. These highly conjugated molecules often have interesting photonic and/or electronic properties that afford them the potential for application in a host of organoelectronic devices such as sensors, light-emitting diodes, photovoltaic devices and field-effect transistors. Here, we show the development and use of the domino hexadehydro-Diels-Alder reaction to synthesize structurally diverse polyacenes from acyclic polyyne precursors. The key event in these transformations is the successive reaction of multiple 1,3-butadiyne units with a series of in-situ-generated, diynophilic arynes. The polyyne substrates were designed to allow for rapid engagement of each progressively larger aryne following the initiating (and ratelimiting) production of the first reactive intermediate-the benzyne. We show that aryne-trapping reactions are broad in scope and that these cascade or domino processes can be quite efficient.


Assuntos
Alquinos/síntese química , Derivados de Benzeno/síntese química , Poli-Inos/química , Alquinos/química , Derivados de Benzeno/química , Reação de Cicloadição , Estrutura Molecular
7.
Int J Nanomedicine ; 13: 3251-3261, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910613

RESUMO

Background: Melittin, the main active peptide ingredient of bee venom, can cause severe cell membrane lysis due to its robust interaction with negatively charged phospholipids. So far, no effective anti-melittin vaccine has been developed to protect people from undesired melittin intoxication. Methods: Herein, we prepared a polydiacetylene (PDA) nanoparticle with cell membrane-mimic surface to complex melittin, forming an anti-melittin vaccine (PDA-melittin). Results: PDA nanoparticles could effectively combine with melittin and neutralize its toxicity. PDA-melittin nanocomplex is demonstrated to enhance melittin uptake by DCs and stimulate strong melittin-specific immunity. Mice immunized with PDA-melittin nanocomplex showed higher survival rate after exposion to melittin than untreated mice. Conclusion: The PDA-melittin nanocomplex can efficiently and safely generate a specific immunity against melittin to protect body from melittin intoxication, providing a new method with potential clinical application for the treatment of melittin intoxication.


Assuntos
Venenos de Abelha/química , Meliteno/imunologia , Nanopartículas/química , Vacinas/química , Vacinas/imunologia , Células 3T3 , Animais , Venenos de Abelha/toxicidade , Biomimética , Células Dendríticas , Feminino , Meliteno/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Polímero Poliacetilênico , Polímeros/química , Poli-Inos/química , Toxoides/imunologia , Vacinas/farmacologia
8.
Macromol Rapid Commun ; 39(20): e1800072, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29756311

RESUMO

Core/shell particles constructed by polymer shell and silica core have constituted a significant category of advanced functional materials. However, constructing microsized optically active helical polymer core/shell particles still remains as a big academic challenge due to the lack of effective and universal preparation methods. In this study, a seed-surface grafting precipitation polymerization (SSGPP) strategy is developed for preparing microsized core/shell particles with SiO2 as core on which helically substituted polyacetylene is covalently bonded as shell. The resulting core/shell particles exhibit fascinating optical activity and efficiently induce enantioselective crystallization of racemic threonine. Taking advantage of the preparation strategy, novel achiral polymeric and hybrid core/shell particles are also expected.


Assuntos
Nanopartículas/química , Polímeros/química , Poli-Inos/química , Dióxido de Silício/química , Cristalização , Óptica e Fotônica , Tamanho da Partícula , Polimerização , Polímeros/síntese química , Poli-Inos/síntese química , Estereoisomerismo
9.
Org Lett ; 20(12): 3536-3540, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29792438

RESUMO

The isolation and structure elucidation of collimonins A-D (1-4) from the fungus-feeding bacterium Collimonas fungivorans Ter331 are reported. Collimonins are new derivatives of polyoxygenated hexadecanoic acid, including an ene-triyne moiety. Their absolute configurations were fully determined by combining spectroscopic, chemical, and crystalline sponge methods. Collimonins showed antifungal or pigmentation activities against the fungus Aspergillus niger ATCC 9029.


Assuntos
Poli-Inos/química , Antifúngicos , Estrutura Molecular , Oxalobacteraceae , Pigmentação
10.
Life Sci ; 204: 55-64, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29733848

RESUMO

AIMS: Ischemic acute kidney injury (AKI) is a serious clinical problem and no efficient therapeutics is available in clinic now. Natural polyacetylene glycosides (PGAs) had shown antioxidant and anti-inflammatory properties, but their effects on kidney injury have not been evaluated. This study aimed to investigate the protective effect of PGA on ischemic kidney injury in renal tubular epithelial cells (TECs) and mice. MAIN METHODS: Hypoxic HK-2 cells and renal ischemia/reperfusion injury (IRI) mice were treated with PGA from Coreopsis tinctoria, and the cell viability, renal function, apoptosis, inflammation, mitochondrial injury, lipids metabolism were analyzed. KEY FINDINGS: In vitro results showed that PGA improved cell viability and reduced oxidative stress, pro-apoptotic/pro-inflammatory factors expression and NFκB activation in TECs under hypoxia/reperfusion (H/R). Moreover, PGA reduced mitochondria oxidative stress and improved ATP production, ΔΨm and mitochondria biogenesis, and inhibited lipids uptake, biosynthesis and accumulation in hypoxic TECs. In vivo, PGA significantly attenuated kidney injury and reduced blood urea nitrogen (BUN), serum creatinine (CREA) and urinary albumin (Alb), and increased creatinine clearance (CC) in IRI mice. PGA also decreased cell apoptosis, mitochondria oxidative stress, inflammatory response and lipid droplets accumulation, and promoted ATP generation in kidney of IRI mice. SIGNIFICANCE: Our results proved that PGA ameliorated ischemic kidney injury via synergic anti-inflammation, mitochondria protection and anti-lipotoxicity actions, and it might be a promising multi-target therapy for ischemic AKI.


Assuntos
Lesão Renal Aguda/prevenção & controle , Anti-Inflamatórios não Esteroides/farmacologia , Transtornos do Metabolismo dos Lipídeos/tratamento farmacológico , Doenças Mitocondriais/tratamento farmacológico , Poli-Inos/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Lesão Renal Aguda/complicações , Albuminúria/prevenção & controle , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Nitrogênio da Ureia Sanguínea , Sobrevivência Celular/efeitos dos fármacos , Coreopsis/química , Creatinina/sangue , Inflamação , Testes de Função Renal , Transtornos do Metabolismo dos Lipídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Mitocondriais/etiologia , Estresse Oxidativo/efeitos dos fármacos , Poli-Inos/química , Circulação Renal , Traumatismo por Reperfusão/complicações
11.
Chem Commun (Camb) ; 54(36): 4561-4564, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29663008
12.
Molecules ; 23(4)2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29649098

RESUMO

Three new polyynes, named choushenpilosulynes A-C (1-3), were isolated from an 85% aqueous EtOH extract of the roots of Codonopsis pilosula cultivated in Xundian County of Yunnan province, China. Their structures, including the absolute configuration of the glucose residue in 1 and 2, were determined by spectroscopic analysis and gas chromatography (GC). In addition, biological evaluation shows that all the compounds can inhibit the expression of the squalene monooxygenase (SQLE) gene in HepG2 cells, suggesting that these compounds may be involved in lipid metabolism.


Assuntos
Codonopsis/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Poli-Inos/isolamento & purificação , Poli-Inos/farmacologia , Esqualeno Mono-Oxigenase/genética , Sobrevivência Celular/efeitos dos fármacos , China , Cromatografia Gasosa , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Poli-Inos/química
13.
J Asian Nat Prod Res ; 20(6): 531-537, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29614875

RESUMO

Phytochemical investigation on the rhizomes of Atractylodes lancea led to the isolation of two new thiophene polyacetylene glycosides (1 and 2) and six known compounds (3-8). Their structures were elucidated based on the extensive spectroscopic data (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of new compounds were established by calculated and experimental circular dichroism. All the compounds were assessed on the lipopolysaccharide-induced NO production in BV2 cells and compounds 3, 7, and 8 showed moderate inhibitory activities.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Atractylodes/química , Glicosídeos , Anti-Inflamatórios/química , Glicosídeos/química , Glicosídeos/isolamento & purificação , Estrutura Molecular , Poli-Inos/química , Poli-Inos/isolamento & purificação , Tiofenos/química , Tiofenos/isolamento & purificação
14.
Chem Commun (Camb) ; 54(29): 3613-3616, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29577125

RESUMO

Polydiacetylene micelles were functionalized with controlled amounts of biotin using bioorthogonal click chemistry. The biotinylated micelles were evaluated in the selective targeting of the MCF-7 cancerous cell line and were shown to be readily internalized. The efficiency of the cellular uptake was correlated to the density of grafted biotin.


Assuntos
Biotina/análogos & derivados , Micelas , Polímeros/química , Poli-Inos/química , Biotina/metabolismo , Biotinilação , Química Click , Humanos , Células MCF-7 , Polímero Poliacetilênico , Polimerização , Polímeros/síntese química , Polímeros/metabolismo , Poli-Inos/síntese química , Poli-Inos/metabolismo , Receptores de Fatores de Crescimento/metabolismo
15.
Chem Commun (Camb) ; 54(16): 2008-2011, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29411793

RESUMO

Classical synthetic approaches to highly unsaturated polyene/yne natural products rely on iterative cross-coupling of linear fragments. Herein, we present an expeditious and unified approach to the unsaturated backbone of polyacetylenes via domino cuprate addition/4π-electrocyclic ring opening of a stereodefined cyclobutene intermediate. This sets the stage for a detailed biological assessment of the role of Virol A and Cicutoxin as inhibitors of GABA induced chloride currents, providing further insight into the interaction of these highly potent toxins towards the GABAA receptor, including the structure-activity relationship of the derivatives.


Assuntos
Produtos Biológicos/farmacologia , Di-Inos/farmacologia , Álcoois Graxos/farmacologia , Poli-Inos/farmacologia , Receptores de GABA-A/metabolismo , Produtos Biológicos/síntese química , Produtos Biológicos/química , Di-Inos/síntese química , Di-Inos/química , Álcoois Graxos/síntese química , Álcoois Graxos/química , Humanos , Estrutura Molecular , Poli-Inos/química , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/metabolismo , Receptores de GABA-A/química , Água/química
16.
Chemistry ; 24(17): 4255-4258, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29431883

RESUMO

We report a cross-reactive sensor array, combining a two-component probe system based upon three viologen substituted boronic acids and a poly(aryleneethynylene) (PAE) and an additional number of simple PAEs alone. This combined system discriminates 27 different honeys in aqueous solution, according to patterns in fluorescence intensity modulation, using linear discriminant analysis for data processing. The fluorescence turn-on array detects saccharide composition, while the PAEs discriminate trace colored components in the honeys.


Assuntos
Técnicas Biossensoriais/métodos , Ácidos Borônicos/química , Corantes Fluorescentes/química , Xarope de Milho Rico em Frutose/análise , Mel/análise , Polímeros/química , Poli-Inos/química , Viologênios/química , Carboidratos/análise , Humanos , Espectrometria de Fluorescência , Água/química
17.
Biomaterials ; 161: 11-23, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29421548

RESUMO

The evolved resistance of antibiotics exhibited by some dreaded clinical pathogens and formation of biofilms has caused life-threatening problems for patients with burns and other wounds. Here, in order to avoid antibiotic overuse, and thus decreasing the occurrence of antimicrobial-resistant bacteria, a theranostic wound dressing, composed of biocompatible UV-photocrosslinkable methacrylated gelatin (GelMA) encapsulating both antimicrobial and fluorescent vesicles, has been developed. The system can respond to the microbiological environment of the wound via a simple color change and antimicrobials release only when require and this is in essence passive as they do not respond to their local environments and benign bacteria, and only operates when pathogenic bacteria exist. Both in Vitro and in Vivo study demonstrated that the proposed wound dressing was able to kill/inhibit the growth of methicillin-resistant S. aureus and P. aeruginosa, whilst providing a visual warning of infection, due to vesicle bilayer membrane lysed by toxins secreted by the two strains of pathogens but not by a non-pathogenic Escherichia coli species. The strategy of microbiologically responsive wound dressing proposed here could also be used as a general methodology for the design and fabrication of bacterial responsive functional biomaterials that offer opportunities to combat drug-resistant bacterial infections.


Assuntos
Bandagens , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Infecções Bacterianas/prevenção & controle , Biofilmes/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Polímero Poliacetilênico , Polímeros/química , Poli-Inos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Coelhos
18.
Molecules ; 23(1)2018 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-29300355

RESUMO

Polydiacetylene (PDA) has attracted interest for use as a sensing platform in biomedical, environmental, and chemical engineering applications owing to its capacity for colorimetric and fluorescent transition in response to external stimuli. Many researchers have attempted to develop a tailor-made PDA sensor via conjugation of chemical or biological substances to PDA. Here, we review smart bio-conjugates of PDA with various biomolecules such as carbohydrates, lipids, nucleic acids, and proteins. In addition, materialization and signal amplification strategies to improve handling and sensitivity are described.


Assuntos
Técnicas Biossensoriais/métodos , Polímeros/química , Poli-Inos/química , Carboidratos/química , Humanos , Lipídeos/química , Ácidos Nucleicos/química , Polímero Poliacetilênico , Proteínas/química
19.
Nat Methods ; 15(3): 194-200, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29334378

RESUMO

Optical multiplexing has a large impact in photonics, the life sciences and biomedicine. However, current technology is limited by a 'multiplexing ceiling' from existing optical materials. Here we engineered a class of polyyne-based materials for optical supermultiplexing. We achieved 20 distinct Raman frequencies, as 'Carbon rainbow', through rational engineering of conjugation length, bond-selective isotope doping and end-capping substitution of polyynes. With further probe functionalization, we demonstrated ten-color organelle imaging in individual living cells with high specificity, sensitivity and photostability. Moreover, we realized optical data storage and identification by combinatorial barcoding, yielding to our knowledge the largest number of distinct spectral barcodes to date. Therefore, these polyynes hold great promise in live-cell imaging and sorting as well as in high-throughput diagnostics and screening.


Assuntos
Corantes Fluorescentes/química , Imagem Óptica/instrumentação , Imagem Óptica/métodos , Poli-Inos/química , Análise Espectral Raman/métodos , Sobrevivência Celular , Células HeLa , Humanos , Óptica e Fotônica
20.
Int J Pharm ; 536(1): 434-439, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29208412

RESUMO

Polydiacetylene (pDA) micelles have been demonstrated to be effective drug carriers for cancer therapy in mouse model. However, little is known about their interaction with the human complement system, which constitutes an important part of the innate immune system and can cause severe hypersensitivity reactions. Herein, we investigate the influence of micelle surface charge on the binding of complement protein C1q, the target recognition unit that activates the classical complement pathway and performs a range of other important physiological functions. Besides the classical pathway, we also investigate the surface charge effect on complement activities through the other activation pathways, namely, the MBL-dependent lectin pathway and the alternative pathway. We synthesized three samples of pDA micelles bearing neutral, anionic, and cationic surface charge motifs, respectively. Surface plasmon resonance showed that none of these micelles interacted with C1q. Results from serum complement activation assays indicated that all micelles were inert to complement, except for the anionic pDA micelles, which activated the alternative pathway.


Assuntos
Complemento C1q/química , Imunidade Inata/efeitos dos fármacos , Polímeros/química , Poli-Inos/química , Ativação do Complemento/efeitos dos fármacos , Portadores de Fármacos , Humanos , Lectinas/química , Micelas , Polímero Poliacetilênico
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