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1.
Chin J Nat Med ; 17(6): 461-468, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31262458

RESUMO

In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower (CKF) on lipopolysaccharide (LPS)-induced acute lung injury (ALI). We determined the effect of CKF methanolic extracts on LPS-induced pro-inflammatory mediators NO and prostaglandin E2 (PGE2), production of pro-inflammatory cytokines (IL-1ß, TNF-α, and IL-6), and related protein expression levels of MyD88/TRIF signaling pathways in peritoneal macrophages (PMs). Nuclear translocation of NF-κB-p65 was analyzed by immunofluorescence. For the in vivo experiments, an ALI model was established to detect the number of inflammatory cells and inflammatory factors (IL-1ß, TNF-α, and IL-6) in bronchoalveolar lavage fluid (BALF) of mice. The pathological damage in lung tissues was evaluated through H&E staining. Our results showed that CKF can decrease the production of inflammatory mediators, such as NO and PGE2, by inhibiting their synthesis-related enzymes iNOS and COX-2 in LPS-induced PMs. In addition, CKF can downregulate the mRNA levels of IL-1ß, TNF-α, and IL-6 to inhibit the production of inflammatory factors. Mechanism studies indicated that CKF possesses a fine anti-inflammatory effect by regulating MyD88/TRIF dependent signaling pathways. Immunocytochemistry staining showed that the CKF extract attenuates the LPS-induced translocation of NF-kB p65 subunit in the nucleus from the cytoplasm. In vivo experiments revealed that the number of inflammatory cells and IL-1ß in BALF of mice decrease after CKF treatment. Histopathological observation of lung tissues showed that CKF can remarkably improve alveolar clearance and infiltration of interstitial and alveolar cells after LPS stimulation. In conclusion, our results suggest that CKF inhibits LPS-induced inflammatory response by inhibiting the MyD88/TRIF signaling pathways, thereby protecting mice from LPS-induced ALI.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Cardamine/química , Fator 88 de Diferenciação Mieloide/metabolismo , Extratos Vegetais/administração & dosagem , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Feminino , Flores/química , Humanos , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/química , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
2.
Mol Cells ; 42(5): 397-405, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31085811

RESUMO

The regulatory role of long noncoding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) in both cancerous and noncancerous cells have been widely reported. This study aimed to evaluate the role of lncRNA GAS5 in heart failure caused by myocardial infarction. We reported that silence of lncRNA GAS5 attenuated hypoxia-triggered cell death, as cell viability was increased and apoptosis rate was decreased. This phenomenon was coupled with the down-regulated expression of p53, Bax and cleaved caspase-3, as well as the up-regulated expression of CyclinD1, CDK4 and Bcl-2. At the meantime, the expression of four heart failure-related miRNAs was altered when lncRNA GAS5 was silenced (miR-21 and miR-142-5p were up-regulated; miR-30b and miR-93 were down-regulated). RNA immunoprecipitation assay results showed that lncRNA GAS5 worked as a molecular sponge for miR-142-5p. More interestingly, the protective actions of lncRNA GAS5 silence on hypoxia-stimulated cells were attenuated by miR-142-5p suppression. Besides, TP53INP1 was a target gene for miR-142-5p. Silence of lncRNA GAS5 promoted the activation of PI3K/AKT and MEK/ERK signaling pathways in a miR-142-5p-dependent manner. Collectively, this study demonstrated that silence of lncRNA GAS5 protected H9c2 cells against hypoxia-induced injury possibly via sponging miR-142-5p, functionally releasing TP53INP1 mRNA transcripts that are normally targeted by miR-142-5p.


Assuntos
Hipóxia Celular , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Linhagem Celular , Proteínas de Choque Térmico , Humanos , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/efeitos dos fármacos , Proteínas Nucleares , Interferência de RNA , RNA Longo não Codificante/uso terapêutico , Ratos
3.
Adv Sci (Weinh) ; 5(7): 1800062, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30027039

RESUMO

Heterojunction photocatalysts at present are still suffering from the low charge separation/transfer efficiency due to the poor charge mobility of semiconductor-based photocatalysts. Atomic-scale heterojunction-type photocatalysts are regarded as a promising and effective strategy to overcome the drawbacks of traditional photocatalysts for higher photoenergy conversion efficiencies. Herein, an atomic-scale heterojunction composed of a boron nitride monolayer and graphene (h-BN-C/G) is constructed to significantly shorten the charge transfer path to promote the activation of molecular oxygen for artificial photosynthesis (exemplified with oxidative coupling of amines to imines). As the thinnest heterojunction, h-BN-C/G gives the highest conversion, which is eightfold higher than that of the mechanical mixture of graphene and boron nitride monolayers. h-BN-C/G exhibits a high turnover frequency value (4.0 mmol benzylamine g-1 h-1), which is 2.5-fold higher than that of the benchmark metal-free photocatalyst in the literature under even critical conditions.

4.
Org Biomol Chem ; 15(31): 6567-6574, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28748978

RESUMO

Degradable polymers as gene and drug carriers are emerging as one of the most promising types of materials in the biomedical and pharmaceutical areas. Herein, we report the synthesis of a series of block co-polyesters (B1-B6) and random co-polyesters (C1-C4) via ring-opening polymerization of tertiary amine-bearing valerolactone and alkylated valerolactone monomers. These polymers can completely inhibit the electrophoretic migrations of plasmid DNAs (pDNAs) at a w/w ratio of 2-6. The polyplexes of these polymers with pDNAs were steadily formed in a narrow range of sizes (75 to 220 nm) and could be effectively internalized into the cytoplasm. The results of transfection experiments showed that the block copolymers generally exhibited better performance than their random counterparts and the aliphatic chain lengths on the backbone of the polymers obviously affected the transfection efficiency (TE). Block copolymer B5 with n-octyl chains generated the best TE in Hek293T cells, which was 2.2 fold that of polyethylenimine (PEI) 25k under the optimal conditions. Moreover, these polymers were found to be more biocompatible compared to PEI 25k, and showed degradable properties. Our results suggest that these polymers are potentially reliable/efficient non-viral gene vectors.


Assuntos
DNA/administração & dosagem , Técnicas de Transferência de Genes , Lactonas/química , Plasmídeos/administração & dosagem , Poliésteres/química , DNA/genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Células HEK293 , Humanos , Lactonas/síntese química , Plasmídeos/genética , Poliésteres/síntese química , Polimerização , Transfecção/métodos
5.
ChemSusChem ; 10(14): 2875-2879, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28612461

RESUMO

Oxygen vacancies can help to capture oxygen-containing species and act as active centers for oxygen evolution reaction (OER). Unfortunately, effective methods for generating a high amount of oxygen vacancies on the surface of various nanocatalysts are rather limited. Here, we described an effective way to generate oxygen-vacancy-rich surface of transition metal oxides, exemplified with Co3 O4 , simply by constructing highly coupled interface of ultrafine Co3 O4 nanocrystals and metallic Ti. Impressively, the amounts of oxygen vacancy on the surface of Co3 O4 /Ti surpassed the reported values of the Co3 O4 modified even under highly critical conditions. The Co3 O4 /Ti electrode could provide a current density of 23 mA cm-2 at an OER overpotential of 570 mV, low Tafel slope, and excellent durability in neutral medium. Because of the formation of a large amount of oxygen vacancies as the active centers for OER on the surface, the TOF value of the Co3 O4 @Ti electrode was optimized to be 3238 h-1 at an OER overpotential of 570 mV, which is 380 times that of the state-of-the-art non-noble nanocatalysts in the literature.


Assuntos
Cobalto/química , Nanopartículas/química , Nanotecnologia , Óxidos/química , Oxigênio/química , Titânio/química , Água/química , Animais , Eletroquímica , Eletrodos , Engenharia , Oxirredução
6.
J Am Chem Soc ; 139(2): 811-818, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28006898

RESUMO

Heterogeneous catalysts of inexpensive and reusable transition-metal are attractive alternatives to homogeneous catalysts; the relatively low activity of transition-metal nanoparticles has become the main hurdle for their practical applications. Here, the de novo design of a Mott-Schottky-type heterogeneous catalyst is reported to boost the activity of a transition-metal nanocatalyst through electron transfer at the metal/nitrogen-doped carbon interface. The Mott-Schottky catalyst of nitrogen-rich carbon-coated cobalt nanoparticles (Co@NC) was prepared through direct polycondensation of simple organic molecules and inorganic metal salts in the presence of g-C3N4 powder. The Co@NC with controllable nitrogen content and thus tunable Fermi energy and catalytic activity exhibited a high turnover frequency (TOF) value (8.12 mol methyl benzoate mol-1 Co h-1) for the direct, base-free, aerobic oxidation of benzyl alcohols to methyl benzoate; this TOF is 30-fold higher than those of the state-of-the-art transition-metal-based nanocatalysts reported in the literature. The presented efficient Mott-Schottky catalyst can trigger the synthesis of a series of alkyl esters and even diesters in high yields.

7.
J Am Soc Nephrol ; 27(2): 495-508, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26109319

RESUMO

Retinoic acid (RA) has been used therapeutically to reduce injury and fibrosis in models of AKI, but little is known about the regulation of this pathway and what role it has in regulating injury and repair after AKI. In these studies, we show that RA signaling is activated in mouse and zebrafish models of AKI, and that these responses limit the extent of injury and promote normal repair. These effects were mediated through a novel mechanism by which RA signaling coordinated the dynamic equilibrium of inflammatory M1 spectrum versus alternatively activated M2 spectrum macrophages. Our data suggest that locally synthesized RA represses proinflammatory macrophages, thereby reducing macrophage-dependent injury post-AKI, and activates RA signaling in injured tubular epithelium, which in turn promotes alternatively activated M2 spectrum macrophages. Because RA signaling has an essential role in kidney development but is repressed in the adult, these findings provide evidence of an embryonic signaling pathway that is reactivated after AKI and involved in reducing injury and enhancing repair.


Assuntos
Lesão Renal Aguda/etiologia , Macrófagos/fisiologia , Transdução de Sinais , Tretinoína/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C
8.
Huan Jing Ke Xue ; 36(4): 1309-16, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26164905

RESUMO

The high-density sampling of eutrophic water can help to reveal the general rules of phytoplankton community succession and the relationship with environmental factors. The species and abundance of plankton and the physical-chemical factors were tracked for 30 weeks from March to October in a eutrophicated small pond. The relationships between the phytoplankton community dynamic change and the physical-chemical factors as well as the zooplankton in the water body community were studied by the multivariate statistical analysis with PRIMER. A total of 54 phytoplankton and 55 zooplankton species were identified, and the abundances of plankton varied from 0.28 x 10(8) - 6.11 x 10(8) cells x L(-1) for phytoplankton and 26-2.5 x 10(5) ind x L(-1) for zooplankton. The dominant species of phytoplankton were Cyanophyta and Chlorophyta, and an obvious succession process was showed with the seasonal change, which could be roughly divided into three stages: Chlorophyta-Cryptophyta type, Chlorophyta-Cyanophyta type and Cyanophyta type. BIO-ENV showed that pH, water temperature, transparency, total phosphorus and the abundances of Rotifera and Copepoda were the most critical influencing factors on the community dynamics of phytoplankton, and compared to zooplankton, the physical-chemical factors might have a greater influence.


Assuntos
Eutrofização , Fitoplâncton/crescimento & desenvolvimento , Tanques , Animais , Clorófitas , Cianobactérias , Fósforo , Zooplâncton
9.
Talanta ; 135: 102-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25640132

RESUMO

Determination of protein concentration in mild environments is of great significance in the clinic diagnose and bioassay. Herein, a simple, fast and sensitive method for protein quantitative determination in neutral solution (pH 7.0) is developed. This assay is based on competition adsorption of the sample protein and fluorescently labeled dog serum albumin (FITC-DSA) onto gold nanoparticles (AuNPs). As the competitor FITC-DSA molecules are added into the mixture solution of sample protein conjugated AuNPs, they will compete for active sites of AuNPs, resulting in decrease in fluorescence intensity due to the quenching effect of AuNPs via fluorescence resonance energy transfer (FRET). Thus, quantitative determination of sample protein concentration can be achieved. Under the optimum conditions, the decrease in fluorescence intensity of the solution is related to the concentration of sample protein and a low detection limit of 0.01 µg/mL BSA can be achieved in 5 min. For the validation of our strategy in practical applications, the total protein content in human serum was determined using the as-proposed method. The result is in well agreement with that of measured by other conventional methods, suggesting a simple, accurate, and mild approach for protein detection in bioassay.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Proteínas/análise , Adsorção , Fluorescência , Humanos , Soro/química , Albumina Sérica/química
10.
Am J Physiol Renal Physiol ; 306(5): F496-504, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24370591

RESUMO

Phenylthiobutanoic acids (PTBAs) are a new class of histone deacetylase (HDAC) inhibitors that accelerate recovery and reduce postinjury fibrosis after ischemia-reperfusion-induced acute kidney injury. However, unlike the more common scenario in which patients present with protracted and less clearly defined onset of renal injury, this model of acute kidney injury gives rise to a clearly defined injury that begins to resolve over a short period of time. In these studies, we show for the first time that treatment with the PTBA analog methyl-4-(phenylthio)butanoate (M4PTB) accelerates recovery and reduces postinjury fibrosis in a progressive model of acute kidney injury and renal fibrosis that occurs after aristolochic acid injection in mice. These effects are apparent when M4PTB treatment is delayed 4 days after the initiating injury and are associated with increased proliferation and decreased G2/M arrest of regenerating renal tubular epithelial cells. In addition, there is reduced peritubular macrophage infiltration and decreased expression of the macrophage chemokines CX3Cl1 and CCL2. Since macrophage infiltration plays a role in promoting kidney injury, and since renal tubular epithelial cells show defective repair and a marked increase in maladaptive G2/M arrest after aristolochic acid injury, these findings suggest M4PTB may be particularly beneficial in reducing injury and enhancing intrinsic cellular repair even when administered days after aristolochic acid ingestion.


Assuntos
Lesão Renal Aguda/tratamento farmacológico , Butiratos/farmacologia , Sulfetos/farmacologia , Lesão Renal Aguda/induzido quimicamente , Animais , Ácidos Aristolóquicos/farmacologia , Butiratos/análise , Modelos Animais de Doenças , Fibrose/tratamento farmacológico , Fibrose/prevenção & controle , Inibidores de Histona Desacetilases/farmacologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Camundongos , Camundongos Biozzi , Traumatismo por Reperfusão/induzido quimicamente , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Sulfetos/análise
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