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Solar powered water evaporation is a green and environmentally friendly water treatment technology, which is a hot research topic for water purification at present. Advanced structural design and hydrophilic photothermal materials have achieved efficient solar evaporation of pure water, but the long-term stability of high salinity desalination has become a problem that cannot be ignored in practical applications. In order to solve this problem, a hydrophobic honeycomb structure MXene/AuNFs composite membrane was proposed in this paper, which used the three-dimensional highly porous microstructure of MXene and multibranched structure of gold nanoflowers particles to improve the light absorption and photothermal conversion efficiency of MXene/AuNFs. At the same time, the surface of the composite membrane was modified with hydrophobic fluorosilane 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFTE). The hydrophobic layer can prevent the accumulation of salt particles on the surface of the membrane, so that the composite film can continue to produce water vapor in a high salt environment. With high utilization rate of light energy, multiple-level geometrical structures of MXene for rapid water transport on the filter membrane and salt barrier on the membrane good stability, the hydrophobic MXene/AuNFs achieves solar evaporation rate of 1.59 kg m-2 h-1 and solar conversion efficiency is 97.8%, and stable operation under simulated sea water conditions under one sun irradiation over more than 10 cycles. The hydrophobic MXene/AuNFs membrane proved to be an efficient and stable photothermal material for solar desalination.
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Polo-like kinase 1 (PLK1) is an attractive therapeutic target for the treatment of tumors, as it is an essential cell-cycle regulator frequently overexpressed in tumor tissues. PLK1 can promote tumor invasion and metastasis, and is often associated with poor prognosis in cancer patients. However, no PLK1 inhibitor has been granted marketing approval until now. Therefore, more potentially promising PLK1 inhibitors need to be investigated. In this study, a series of novel inhibitors targeting PLK1 was designed and optimized derived from a new scaffold. After synthesis and characterization, we obtained the structure-activity relationship and led to the discovery of the most promising compound 30e for PLK1. The antiproliferative activity against HCT116 cells (IC50 = 5 nM versus 45 nM for onvansertib) and the cellular permeability and efflux ratio were significantly improved (PappAâB = 2.03 versus 0.345 and efflux ratio = 1.65 versus 94.7 for 30e and onvansertib, respectively). Further in vivo studies indicated that 30e had favorable antitumor activity with 116.2% tumor growth inhibition (TGI) in comparison with TGI of 43.0% for onvansertib. Furthermore, 30e improved volume of tumor tissue distribution in mice as compared to onvansertib. This initial study on 30e holds promise for further development of an antitumor agent.
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Neoplasias , Inhibidores de Proteínas Quinasas , Animales , Ratones , Inhibidores de Proteínas Quinasas/farmacología , Proteínas de Ciclo Celular , Proteínas Serina-Treonina Quinasas , Línea Celular Tumoral , Proliferación Celular , Quinasa Tipo Polo 1RESUMEN
PLK-1 (Polo-like kinase-1) plays an essential role in cytokinesis, and its aberrant expression is considered to be keenly associated with a wide range of cancers. It has been selected as an appealing target and small-molecule inhibitors have been developed and studied in clinical trials. Unfortunately, most have been declared as failures due to the poor therapeutic response and off-target toxicity. In the present study, a novel potent PLK-1 inhibitor, compound 7a, was designed and synthetized. 1H NMR, 13C NMR, 19F NMR and mass spectrum were comprehensively used for the compound characterization. The compound exhibited higher potency against PLK-1 kinase, HCT-116 and NCI-H2030 cell lines than the positive control. Molecular docking indicated that the binding mode that the ATP binding site of PLK-1 was occupied by the compound. Then, a UHPLC-MS/MS method was established and validated to explore the pharmacokinetic behavior of the drug candidate. The method had good selectivity, high sensitivity and wide linearity. The exposure increased linearly with the dose, but the oral bioavailability was not satisfactory enough. Then, the metabolism was studied using liver microsomes by UHPLC-Q-Orbitrap/HRMS. Our research first studied the pharmacokinetic metabolic characteristics of 7a and may serve as a novel lead compound for the development of PLK-1 inhibitors.
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Metaboloma , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Simulación del Acoplamiento Molecular , Disponibilidad BiológicaRESUMEN
To study the effect of acute-phase reaction (APR) of inflammation on the release of octreotide acetate microsphere (Sandostatin®, SLAR) at a clinical dose, a more sensitive liquid chromatography coupled to tandem mass spectrometry analysis method needs to be developed because of the low plasma concentrations of octreotide. Solid-phase microextraction with an Oasis® HLB µElution plate was adopted for sample preparation. Extraction recovery ranged from 65.7 % to 73.2 %, and the matrix effect was negligible. High sensitivity and an intense chromatographic peak were acquired by optimizing the chromatography and mass spectrometry conditions. The lower limit of quantitation (LLOQ) was 0.01 ng/mL based on 100 µL of plasma, and linearity ranged from 0.01 to 5.0 ng/mL. The coefficients of variations for intraday and interday precision were less than 4.4 %, and the relative error of accuracy was within 5.7 %. The validated method was successfully applied to pharmacokinetics studies of SLAR in a seven-day inflammation model of rabbits, indicating that the APR did not affected the release and pharmacokinetics of the octreotide microspheres.
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Octreótido , Espectrometría de Masas en Tándem , Animales , Conejos , Espectrometría de Masas en Tándem/métodos , Microesferas , Cromatografía Liquida/métodos , Inflamación , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: The application of clinical mNGS for diagnosing respiratory infections improves etiology diagnosis, however at the same time, it brings new challenges as an unbiased sequencing method informing all identified microbiomes in the specimen. METHODS: Strategy evaluation and metagenomic analysis were performed for the mNGS data generated between March 2017 and October 2019. Diagnostic strengths of four specimen types were assessed to pinpoint the more appropriate type for mNGS diagnosis of respiratory infections. Microbiome complexity was revealed between patient cohorts and infection types. A bioinformatic pipeline resembling diagnosis results was built based upon multiple bioinformatic parameters. RESULTS: The positive predictive values (PPVs) for mNGS diagnosing of non-mycobacterium, Nontuberculous Mycobacteria (NTM), and Aspergillus were obviously higher in bronchoalveolar lavage fluid (BALF) demonstrating the potency of BALF in mNGS diagnosis. Lung tissues and sputum were acceptable for diagnosis of the Mycobacterium tuberculosis (MTB) infections. Interestingly, significant taxonomy differences were identified in sufficient BALF specimens, and unique bacteriome and virome compositions were found in the BALF specimens of tumor patients. Our pipeline showed comparative diagnostic strength with the clinical microbiological diagnosis. CONCLUSIONS: To achieve reliable mNGS diagnosis result, BALF specimens for suspicious common infections, and lung tissues and sputum for doubtful MTB infections are recommended to avoid the false results given by the complexed respiratory microbiomes. Our developed bioinformatic pipeline successful helps mNGS data interpretation and reduces manual corrections for etiology diagnosis.
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Microbiota , Mycobacterium tuberculosis , Infecciones del Sistema Respiratorio , Humanos , Metagenómica/métodos , Microbiota/genética , Líquido del Lavado Bronquioalveolar/microbiología , Infecciones del Sistema Respiratorio/diagnóstico , Sensibilidad y EspecificidadRESUMEN
The gonadotropin releasing hormone receptor (GnRH-R) is a G protein-coupled receptor (GPCR) belonging to the rhodopsin family. GnRH-R antagonists suppress testosterone to castrate level more rapidly than gonadotropin releasing hormone agonists but lack the flare phenomenon often seen during the early period of GnRH-R agonist treatment. Recently orgovyx (relugolix) was approved as the first oral GnRH-R antagonist for the treatment of advanced prostate cancer. However, orgovyx has demonstrated poor pharmacokinetic profile with low oral bioavailability and high efflux. Here, we rationally designed and synthesized a series of derivatives (13a-m, 21a-i) through the modification and structure-activity relationship study of relugolix, which led to the discovery of 21a as a highly potent GnRH-R antagonist (IC50 = 2.18 nM) with improved membrane permeability (Papp, A-B = 0.98 × 10-6 cm/s) and oral bioavailability (F % = 44.7). Compound 21a showed high binding affinity (IC50 = 0.57 nM) and potent in vitro antagonistic activity (IC50 = 2.18 nM) at GnRH-R. 21a was well tolerated and efficacious in preclinical studies to suppress blood testosterone levels, which merits further investigation as a candidate novel GnRH-R antagonist for clinical studies.
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Receptores LHRH , Rodopsina , Hormona Liberadora de Gonadotropina , Humanos , Masculino , Compuestos de Fenilurea , Pirimidinas , Pirimidinonas , Receptores LHRH/metabolismo , TestosteronaRESUMEN
Objective: The present network meta-analysis (NMA) was conducted to summarize the direct and indirect evidence of common programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) inhibitors including avelumab, atezolizumab, cemiplimab, nivolumab, and pembrolizumab for the treatment of non-small cell lung cancer (NSCLC) patients and further to determine the optimal therapeutic regimen. Methods: We performed a systematic literature search to identify all potentially eligible studies in PubMed, Embase, and the Cochrane Library until August 7, 2021. The primary outcome was overall survival (OS), and the second outcome was treatment-related adverse events (TRAEs). We used random-effects model to conduct direct and network meta-analyses, which were performed by using RevMan 5.3 and R version 3.6.1, respectively. Results: Direct meta-analysis suggested that atezolizumab, cemiplimab, nivolumab, or pembrolizumab significantly improved OS compared with chemotherapy (CT), and NMA further established that atezolizumab [hazard ratio (HR), 0.77; 95% CrI, 0.62-0.96], nivolumab (HR, 0.75; 95% CrI, 0.62-0.93), or pembrolizumab (HR, 0.71; 95% Credible interval (Crl), 0.57-0.89) significantly and cemiplimab (HR, 0.68; 95% CrI, 0.46-1.02) numerically improved OS compared with CT. Meanwhile, NMA also indicated that cemiplimab was numerically superior to other PD-1/PD-L1 agents. Moreover, avelumab, atezolizumab, cemiplimab, nivolumab, and pembrolizumab were found to have fewer TRAEs compared with CT in direct meta-analysis, which were supported by the results from the NMA. Meanwhile, surface under the cumulative ranking curve (SUCRA) and ranking probability suggested that cemiplimab provided the most favorable balance between efficacy and safety, with the first ranking for the OS. Conclusions: Based on available evidence, cemiplimab may have the most favorable risk-benefit ratio for NSCLC patients compared with other common therapeutic management. However, future research with a large-scale, high-quality, and mature follow-up is needed to further determine which agents should be preferentially selected for NSCLC patients due to the limitations of our NMA and variations of eligible studies in treatment line and PD-L1 status.
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Global dissemination of K. pneumoniae clones poses health hazards to the public. Genomic epidemiology studies with comprehensive data set further revealed clone divergence, showing a high complexity in evolution. Moreover, clones carrying both acquired virulent and antimicrobial-resistant genes emerged and might replace the carbapenem-resistant clones. Co-occurrence of virulence and resistance is emerging. An unbiased collection of 3,061 clinical K. pneumoniae isolates (January 5, 2013 to July 24, 2018) underwent whole-genome sequencing. Pairwise core-genome single-nucleotide polymorphism (cgSNP) distances identified clone divergence and transmission events. A sum of 2,193 nonduplicated genomes clustered into four phenotypically indistinguishable species complexes. 93% (n = 2,035) were KpI with its largest clonal group (CG) being CG11 (n = 406). Three hundred ninety-three were ST11 and three hundred seventy-four carried blaKPC-2. Noticeably, CG11 is divided into two main subclones based on the capsule synthesis K loci (KL). CG11-KL64 showed a clear hypervirulent plus antimicrobial-resistant (hv+AMR) characteristic. Besides, the phylogenetic structure revealed the clone divergence of CG25, and this is the first report with sufficient CG25 genomes to identify the divergence. The outcomes of the hv+AMR CG25 cluster 1 affected patients were poorer (P < 0.05). Moreover, two episodes of strain transmissions were associated with CG25 cluster 1. Other transmissions were associated with ST20 and ST307. Genomic epidemiology identified clone divergence of CG11 and CG25. The hv+AMR subclones pose greater threats on a global scale. Nosocomial transmissions of the high-risk clones raised our concerns about the evolution and transmission of emerging clones among newborns and critically ill patients. IMPORTANCE The convergence of AMR and acquired virulence posing higher risks to the public is a focusing point. With sufficient genomes and genotypes, we successfully identify the convergence in two subclones, the previously reported CG11-KL64, and the newly reported CG25 cluster 1. The novel finding of the CG25 divergence was not only revealed by the phylogenetic tree but also confirmed by the clinical outcome data and the accessory genome patterns. Moreover, the transmission subclones circulated in two clinically important wards highlights the deficiency of infection control program using conventional methods. Without the assistance of whole-genome sequencing, the transmissions of high-risk clones could not be identified.
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Infecciones por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacología , Células Clonales , Farmacorresistencia Bacteriana Múltiple/genética , Genómica , Humanos , Recién Nacido , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/genética , Pruebas de Sensibilidad Microbiana , Filogenia , beta-Lactamasas/genéticaRESUMEN
Colistin is considered the last-line antimicrobial for the treatment of multidrug-resistant gram-negative bacterial infections. The emergence and spread of superbugs carrying the mobile colistin resistance gene (mcr) have become the most serious and urgent threat to healthcare. Here, we discover that silver (Ag+), including silver nanoparticles, could restore colistin efficacy against mcr-positive bacteria. We show that Ag+ inhibits the activity of the MCR-1 enzyme via substitution of Zn2+ in the active site. Unexpectedly, a tetra-silver center was found in the active-site pocket of MCR-1 as revealed by the X-ray structure of the Ag-bound MCR-1, resulting in the prevention of substrate binding. Moreover, Ag+effectively slows down the development of higher-level resistance and reduces mutation frequency. Importantly, the combined use of Ag+ at a low concentration with colistin could relieve dermonecrotic lesions and reduce the bacterial load of mice infected with mcr-1carrying pathogens. This study depicts a mechanism of Ag+ inhibition of MCR enzymes and demonstrates the potentials of Ag+ as broad-spectrum inhibitors for the treatment of mcr-positive bacterial infection in combination with colistin.
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Antibacterianos , Colistina , Farmacorresistencia Bacteriana Múltiple , Proteínas de Escherichia coli , Escherichia coli , Plata , Antibacterianos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Escherichia coli/genética , Proteínas de Escherichia coli/antagonistas & inhibidores , Proteínas de Escherichia coli/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Plata/farmacologíaRESUMEN
A series of Sr3(PO4)2:Ce3+/Mn2+/Tb3+ phosphors were synthesized by a high temperature solid phase method. After introducing Ce3+ as sensitizer in Sr3(PO4)2:Ce3+/Mn2+, the efficient energy transfer from Ce3+ to Mn2+ was observed and analyzed in detail, and Sr3(PO4)2:Ce3+/Mn2+ was demonstrated to be color tunable, changing from blue to orange red. In addition, Tb3+ ion, which mainly emits green light, was further added into the Sr3(PO4)2:Ce3+/Mn2+. Due to the addition of this green emission, the white emitting phosphors with good quality were obtained. At the same time, the energy transfer mechanisms among Ce3+, Tb3+ and Mn2+ ions were also analyzed in detail. The results show that Sr3(PO4)2:Ce3+/Mn2+/Tb3+ is a promising candidate for white light emitting diodes.
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A series of deep red phosphors with perovskite-like oxide LaSrGaO4 as host are synthesized by a high temperature solid state method, and the luminescence properties and mechanisms have been investigated in detail. LaSrGaO4 presents self-luminescence at 722 nm, and it is proved that the self-luminescence comes from two kinds of electronic defects and three kinds of vacancy defects, which are anti-occupation defects La Srâ¢, strontium gap defects Sr iâ¢â¢, the oxygen interstitial defects O iâ³, substitution defects Sr La', and strontium vacancy defects V Srâ³. In addition, when Mn2+ ions are doped in LaSrGaO4, interestingly, the shape of the emission spectra of LaSrGaO4:Mn2+ is the same as that of LaSrGaO4, and the emission intensities are enhanced greatly. Luminescence of Mn2+ ions has been confirmed by doping Mg2+ into LaSrGaO4 and measuring the lifetimes of host LaSrGaO4, LaSrGaO4:Mg2+, and LaSrGaO4:Mn2+ for comparison. The mechanisms of host self-luminescence and Mn2+ luminescence are discussed by detecting the luminescence centers with the low temperature spectra, calculating the forbidden bandwidth with the diffuse reflectance spectra, and calculating the trap depths with the thermoluminescence spectra and further depicted by establishing the transition model. LaSrGaO4:Mn2+ can emit strong deep red light about 722 nm, so the phosphor will have a good application prospect in the field of plant lighting.
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The successful development of bortezomib-based therapy for treatment of multiple myeloma has established proteasome inhibition as an effective therapeutic strategy, and both 20S proteasome peptidases and 19S deubiquitinases (DUBs) are becoming attractive targets of cancer therapy. It has been reported that metal complexes, such as copper complexes, inhibit tumor proteasome. However, the involved mechanism of action has not been fully characterized. Here we report that (i) copper pyrithione (CuPT), an alternative to tributyltin for antifouling paint biocides, inhibits the ubiquitin-proteasome system (UPS) via targeting both 19S proteasome-specific DUBs and 20S proteolytic peptidases with a mechanism distinct from that of the FDA-approved proteasome inhibitor bortezomib; (ii) CuPT potently inhibits proteasome-specific UCHL5 and USP14 activities; (iii) CuPT inhibits tumor growth in vivo and induces cytotoxicity in vitro and ex vivo. This study uncovers a novel class of dual inhibitors of DUBs and proteasome and suggests a potential clinical strategy for cancer therapy.
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Péptido Hidrolasas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Proteolisis/efectos de los fármacos , Proteasas Ubiquitina-Específicas/metabolismo , Animales , Antineoplásicos/farmacología , Ácidos Borónicos/farmacología , Bortezomib , Línea Celular , Línea Celular Tumoral , Células HEK293 , Células Hep G2 , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/metabolismo , Compuestos Organometálicos/farmacología , Inhibidores de Proteasas/farmacología , Pirazinas/farmacología , Piridinas/farmacología , Ubiquitina/metabolismoRESUMEN
A simple Schiff-base receptor 7-methoxychromone-3-carbaldehyde-(pyridylformyl) hydrazone (MCNH) was prepared. It exhibits an "off-on-type" mode with high sensitivity in the presence of Al(3+). This compound could be used as Al(3+) probe in ethanol and it features visible light excitation (433 nm) and emission (503 nm) profiles. Upon binding of Al(3+), a significant fluorescence enhancement with a turn-on ratio over 800-fold was triggered. However, other metal ions had no such significant effect on the fluorescence. MCNH can also be used as a colorimetric chemosensor for Al(3+), which is easily observed from colorless to yellow-green by the naked-eye. The detection limit of MCNH for Al(3+) was as low as 1.9×10(-7) M.
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Aluminio/análisis , Colorantes Fluorescentes/química , Hidrazonas/química , Bases de Schiff/química , Cationes/análisis , Colorimetría/métodos , Límite de Detección , Espectrometría de Fluorescencia/métodosRESUMEN
Bio-refinery using cheap biomass focuses mainly on strain improvement and fermentation strategies whereas less effort is made on down-stream processing. Using cheap biomass more impurities are introduced into the fermentation broths than mono-sugar substrate, thus down-stream processing for bio-based chemicals becomes the key problem in industrial production. The technique called salting-out extraction (SOE) was introduced in this review, which is used to separate target products from fermentation broth on the basis of partition difference of chemicals in two phases formed by mixing salts and organic solvents (or amphipathic chemicals) with broth at suitable ratios. The effect of solvents and salts on the formation of two aqueous phases, especially short chain alcohols and inorganic salts, and the application of SOE in recovery of bio-based chemicals, such as lactic acid, 1,3-propanediol, 2,3-butanediol and acetoin were summarized. The bio-chemicals were efficiently recovered from fermentation broth, and most of the impurities (cells and proteins) were removed in the same step. This technique is promising in the separation of bio-based chemicals, especially the recovery of hydrophilic molecules with low molecular weights.
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Fraccionamiento Químico/métodos , Ácido Láctico/aislamiento & purificación , Glicoles de Propileno/aislamiento & purificación , Solventes/química , Butileno Glicoles/aislamiento & purificación , Butileno Glicoles/metabolismo , Fermentación , Ácido Láctico/metabolismo , Concentración Osmolar , Glicoles de Propileno/metabolismo , Cloruro de Sodio/químicaRESUMEN
Gambogic acid (GA) is a natural compound derived from Chinese herbs that has been approved by the Chinese Food and Drug Administration for clinical trials in cancer patients; however, its molecular targets have not been thoroughly studied. Here, we report that GA inhibits tumor proteasome activity, with potency comparable to bortezomib but much less toxicity. First, GA acts as a prodrug and only gains proteasome-inhibitory function after being metabolized by intracellular CYP2E1. Second, GA-induced proteasome inhibition is a prerequisite for its cytotoxicity and anticancer effect without off-targets. Finally, because expression of the CYP2E1 gene is very high in tumor tissues but low in many normal tissues, GA could therefore produce tissue-specific proteasome inhibition and tumor-specific toxicity, with clinical significance for designing novel strategies for cancer treatment.
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Especificidad de Órganos/efectos de los fármacos , Inhibidores de Proteasoma/farmacología , Xantonas/farmacología , Animales , Caspasas/metabolismo , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Estrés del Retículo Endoplásmico/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Células Hep G2 , Humanos , Células K562 , Leucemia/metabolismo , Leucemia/patología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Linfocitos/patología , Ratones , Simulación del Acoplamiento Molecular , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/química , ARN Interferente Pequeño/metabolismo , Análisis de Supervivencia , Tripsina/metabolismo , Ubiquitinación/efectos de los fármacos , Xantonas/químicaRESUMEN
L-carnitine (LC) is generally believed to transport long-chain acyl groups from fatty acids into the mitochondrial matrix for ATP generation via the citric acid cycle. Based on Warburg's theory that most cancer cells mainly depend on glycolysis for ATP generation, we hypothesize that, LC treatment would lead to disturbance of cellular metabolism and cytotoxicity in cancer cells. In this study, Human hepatoma HepG2, SMMC-7721 cell lines, primary cultured thymocytes and mice bearing HepG2 tumor were used. ATP content was detected by HPLC assay. Cell cycle, cell death and cell viability were assayed by flow cytometry and MTS respectively. Gene, mRNA expression and protein level were detected by gene microarray, Real-time PCR and Western blot respectively. HDAC activities and histone acetylation were detected both in test tube and in cultured cells. A molecular docking study was carried out with CDOCKER protocol of Discovery Studio 2.0 to predict the molecular interaction between L-carnitine and HDAC. Here we found that (1) LC treatment selectively inhibited cancer cell growth in vivo and in vitro; (2) LC treatment selectively induces the expression of p21(cip1) gene, mRNA and protein in cancer cells but not p27(kip1); (4) LC increases histone acetylation and induces accumulation of acetylated histones both in normal thymocytes and cancer cells; (5) LC directly inhibits HDAC I/II activities via binding to the active sites of HDAC and induces histone acetylation and lysine-acetylation accumulation in vitro; (6) LC treatment induces accumulation of acetylated histones in chromatin associated with the p21(cip1) gene but not p27(kip1) detected by ChIP assay. These data support that LC, besides transporting acyl group, works as an endogenous HDAC inhibitor in the cell, which would be of physiological and pathological importance.
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Carnitina/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Neoplasias/enzimología , Neoplasias/patología , Acetilación/efectos de los fármacos , Adenosina Trifosfato/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromatina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Simulación del Acoplamiento Molecular , Neoplasias/genética , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
Combinations of proteasome inhibitors and histone deacetylases (HDAC) inhibitors appear to be the most potent to produce synergistic cytotoxicity in preclinical trials. We have recently confirmed that L-carnitine (LC) is an endogenous HDAC inhibitor. In the current study, the anti-tumor effect of LC plus proteasome inhibitor bortezomib (velcade, Vel) was investigated both in cultured hepatoma cancer cells and in Balb/c mice bearing HepG2 tumor. Cell death and cell viability were assayed by flow cytometry and MTS, respectively. Gene, mRNA expression and protein levels were detected by gene microarray, quantitative real-time PCR and Western blot, respectively. The effect of Vel on the acetylation of histone H3 associated with the p21(cip1) gene promoter was examined by using ChIP assay and proteasome peptidase activity was detected by cell-based chymotrypsin-like (CT-like) activity assay. Here we report that (i) the combination of LC and Vel synergistically induces cytotoxicity in vitro; (ii) the combination also synergistically inhibits tumor growth in vivo; (iii) two major pathways are involved in the synergistical effects of the combinational treatment: increased p21(cip1) expression and histone acetylation in vitro and in vivo and enhanced Vel-induced proteasome inhibition by LC. The synergistic effect of LC and Vel in cancer therapy should have great potential in the future clinical trials.
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Antineoplásicos/farmacología , Ácidos Borónicos/farmacología , Carnitina/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Proteasoma/farmacología , Pirazinas/farmacología , Acetilación/efectos de los fármacos , Animales , Bortezomib , Caspasas/metabolismo , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cromatina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Sinergismo Farmacológico , Estrés del Retículo Endoplásmico/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Células Hep G2 , Histonas/metabolismo , Humanos , Masculino , Ratones , Modelos Biológicos , Poli(ADP-Ribosa) Polimerasas/metabolismo , ARN Interferente Pequeño/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Bdellovibrio-and-like organisms (BALOs) are a group of highly motile delta-proteobacteria that prey on other gram-negative bacteria. However, nothing is known of the application potential of marine BALOs in safeguarding seafood safety. Here, biological characterization of two marine BALOs strains and their application in the elimination of Vibrio parahaemolyticus in oyster (Crassostrea ariakensis) at the laboratory scale were investigated. BALOs strains BDH12 and BDHSH06 were isolated from sediment of Daya bay in Shenzhen of China, with Shewanella putrefaciens strain 12 and V. parahaemolyticus strain SH06 as preys, respectively, when using double layer agar technique. They were identified as BALOs morphologically by transmission electron microscopy, while partial 16S rDNA sequencing analysis revealed that they showed no close relationships with members of the known genera Bdellovibrio, Bacteriolyticum, Bacteriovorax, or Peredibacter. Biological characterizations revealed that both strains had the optimal pH, salinity and temperature at 7.2, 3% and 30 °C, correspondingly. They could not utilize autoclaved, dead cells as hosts. Prey range analysis revealed that individually, BDH12 and BDHSH06 lysed 82.5% (47 strains) and 84.2% (48 strains) of the total 57 preys tested respectively. In combination, they lysed 98.2% (56 of 57) strains. All strains of V. parahaemolyticus, Vibrio cholerae and Vibrio alginolyticus tested could be lysed by both strains. A 7-day laboratory-scale V. parahaemolyticus elimination experiment in oyster showed that in the control, the cell counts of total vibrios and V. parahaemolyticus strain Vp plus in water and in oyster intestines were on the rise, whereas in the BALOs treated groups, their numbers were down from 8.09±0.05 log CFU/ml and 8.02±0.04 log CFU/ml to 2.39±0.01 log CFU/ml and 2.33±0.01 log CFU/ml, respectively. The same patterns could also be observed in oyster intestines. Results of this study indicate the feasibility of using BALOs to biologically control or even eliminate V. parahaemolyticus in seafood oyster.
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Bdellovibrio/aislamiento & purificación , Agentes de Control Biológico , Ostreidae/microbiología , Vibrio parahaemolyticus/crecimiento & desarrollo , Animales , Bdellovibrio/clasificación , Bdellovibrio/genética , Bdellovibrio/crecimiento & desarrollo , China , Recuento de Colonia Microbiana , ADN Bacteriano/genética , Concentración de Iones de Hidrógeno , Filogenia , ARN Ribosómico 16S/genética , Salinidad , Alimentos Marinos/microbiología , Agua de Mar/microbiología , Análisis de Secuencia de ADN , TemperaturaRESUMEN
Several flavonoids have been reported to be proteasome inhibitors, but whether prenylated flavonoids are able to inhibit proteasome function remains unknown. We report for the first time that Sanggenon C, a natural prenylated flavonoid, inhibits tumor cellular proteasomal activity and cell viability. We found that (1) Sanggenon C inhibited tumor cell viability and induced cell cycle arrest at G0/G1 phase; (2) Sanggenon C inhibited the chymotrypsin-like activity of purified human 20S proteasome and 26S proteasome in H22 cell lysate, and Sanggenon C was able to dose-dependently accumulate ubiquitinated proteins and proteasome substrate protein p27; (3) Sanggenon C-induced proteasome inhibition occurred prior to cell death in murine H22 and P388 cell lines; (4) Sanggenon C induced death of human K562 cancer cells and primary cells isolated from leukemic patients. We conclude that Sanggenon C inhibits tumor cell viability via induction of cell cycle arrest and cell death, which is associated with its ability to inhibit the proteasome function and that proteasome inhibition by Sanggenon C at least partially contributes to the observed tumor cell growth-inhibitory activity.