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1.
J Gastroenterol Hepatol ; 39(4): 658-666, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38251791

RESUMO

BACKGROUND AND AIM: Fexuprazan is a novel potassium-competitive acid blocker (P-CAB). This study aimed to explore the noninferior efficacy and safety of fexuprazan to esomeprazole in treating erosive esophagitis (EE). METHODS: This was a phase III, randomized, double-blind multicenter study. Patients with endoscopically confirmed EE were randomized to receive fexuprazan 40 mg or esomeprazole 40 mg once a daily for 4-8 weeks. The healing rates of EE, symptom response, GERD-health-related quality life (GERD-HRQL), and treatment-emergent adverse events (TEAEs) were compared between fexuprazan group and esomeprazole group. RESULTS: A total of 332 subjects were included in full analysis set (FAS) and 311 in per-protocol set (PPS). The healing rates of fexuprazan and esomeprazole groups at 8 weeks were 88.5% (146/165) and 89.0% (145/163), respectively, in FAS and 97.3% (145/149) and 97.9% (143/146), respectively, in PPS. Noninferiority of fexuprazan compared with esomeprazole according to EE healing rates at 8 weeks was demonstrated in both FAS and PPS analysis. No significant difference was found between groups in EE healing rates at 4 weeks, symptom responses, and changes of GERD-HRQL. The incidence of drug-related AEs was 19.4% (32/165) in fexuprazan arm and 19.6% (32/163) in esomeprazole arm. CONCLUSION: This study demonstrated noninferior efficacy of fexuprazan to esomeprazole in treating EE. The incidence of TEAEs was similar between fexuprazan and esomeprazole. Trial registration number NCT05813561.


Assuntos
Aminas , Esofagite Péptica , Refluxo Gastroesofágico , Úlcera Péptica , Pirróis , Humanos , Método Duplo-Cego , Esomeprazol/efeitos adversos , Esofagite Péptica/tratamento farmacológico , Esofagite Péptica/etiologia , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/complicações , Úlcera Péptica/complicações , Inibidores da Bomba de Prótons/efeitos adversos , Resultado do Tratamento
2.
BMC Endocr Disord ; 24(1): 58, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689308

RESUMO

OBJECTIVE: The objective of this study was to evaluate the association between hyperthyroidism and the risk of developing erectile dysfunction (ED). METHODS: A comprehensive search of multiple databases, including PubMed, Embase, Cochrane, and Web of Science, was conducted to identify relevant studies investigating the relationship between hyperthyroidism and ED in men. The quality of the included studies was assessed using the Newcastle‒Ottawa Quality Rating Scale, and a meta-analysis was performed using Stata 16.0 and RevMan 5.3 software. RESULTS: A total of four papers encompassing 25,519 study subjects were included in the analysis. Among these, 6,429 individuals had hyperthyroidism, while 19,090 served as controls. The overall prevalence of ED in patients with hyperthyroidism was determined to be 31.1% (95% CI 0.06-0.56). In patients with uncomplicated hyperthyroidism, the incidence of ED was 21.9% (95% CI 0.05-0.38). The combined odds ratio (OR) for the four studies was 1.73 (OR: 1.73; 95% CI [1.46-2.04]; p < .00001). CONCLUSION: Our findings demonstrate a higher incidence of ED in patients with hyperthyroidism. These results provide valuable information for healthcare professionals and can facilitate discussions surrounding appropriate treatment options for ED in patients with hyperthyroidism.


Assuntos
Disfunção Erétil , Hipertireoidismo , Humanos , Hipertireoidismo/epidemiologia , Hipertireoidismo/complicações , Disfunção Erétil/epidemiologia , Disfunção Erétil/etiologia , Masculino , Prevalência
3.
J Biol Chem ; 298(7): 102095, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35660018

RESUMO

Ascl2 has been shown to be involved in tumorigenesis in colorectal cancer (CRC), although its epigenetic regulatory mechanism is largely unknown. Here, we found that methylation of the Ascl2 promoter (bp -1670 ∼ -1139) was significantly increased compared to the other regions of the Ascl2 locus in CRC cells and was associated with elevated Ascl2 mRNA expression. Furthermore, we found that promoter methylation was predictive of CRC patient survival after analyzing DNA methylation data, RNA-Seq data, and clinical data of 410 CRC patient samples from the MethHC database, the MEXPRESS database, and the Cbioportal website. Using the established TET methylcytosine dioxygenase 2 (TET2) knockdown and ectopic TET2 catalytic domain-expression cell models, we performed glucosylated hydroxymethyl-sensitive quatitative PCR (qPCR), real-time PCR, and Western blot assays to further confirm that hypermethylation of the Ascl2 promoter, and elevated Ascl2 expression in CRC cells was partly due to the decreased expression of TET2. Furthermore, BCLAF1 was identified as a TET2 interactor in CRC cells by LC-MS/MS, coimmunoprecipitation, immunofluorescence colocalization, and proximity ligation assays. Subsequently, we found the TET2-BCLAF1 complex bound to multiple elements around CCGG sites at the Ascl2 promoter and further restrained its hypermethylation by inducing its hydroxymethylation using chromatin immunoprecipitation-qPCR and glucosylated hydroxymethyl-qPCR assays. Finally, we demonstrate that TET2-modulated Ascl2-targeted stem gene expression in CRC cells was independent of Wnt signaling. Taken together, our data suggest an additional option for inhibiting Ascl2 expression in CRC cells through TET2-BCLAF1-mediated promoter methylation, Ascl2-dependent self-renewal of CRC progenitor cells, and TET2-BCLAF1-related CRC progression.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Neoplasias Colorretais , Metilação de DNA , Dioxigenases , Proteínas Repressoras , Proteínas Supressoras de Tumor , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Cromatografia Líquida , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Espectrometria de Massas em Tandem , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
4.
J Environ Manage ; 337: 117749, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36940603

RESUMO

Opal (SiO2·nH2O, amorphous silica), the by-product of alumina extraction from coal fly ash (CFA), has a strong adsorption capacity and is also an important component of clay minerals in soils. The combining of opal with sand to form artificial soils is an effective disposal strategy for large-scale CFA stockpiles and reduction of environmental risk. Nevertheless, its poor physical condition limits plant growth. Organic matter (OM) amendments have broad potential applications for water-holding and improving soil aggregation. Effects of OMs (vermicompost (VC), bagasse (BA), biochar (BC) and humic acid (HA)) on the formation, stability and pore characteristics of opal/sand aggregates were evaluated through 60-day laboratory incubation experiments. Results demonstrated that four OMs could reduce pH, with BC having the most significant effect, VC significantly increasing the electrical conductivity (EC) and TOC content of the aggregates. Except for HA, other OMs could improve the aggregates' water-holding capacity. The mean weight diameter (MWD) and percentage of >0.25 mm aggregates (R0.25) of BA-treated aggregates were the largest, and BA had the most noticeable contribution to macro-aggregate's formation. The best aggregate stability was obtained with HA treatment, meanwhile the percentage of aggregate destruction (PAD0.25) decreased with the addition of HA. After amendments, the proportion of organic functional groups increased, which favored aggregate's formation and stability; the surface pore characteristics were improved, with the porosity ranging from 70% to 75%, reaching the level of well-structured soil. Overall, the addition of VC and HA can effectively promote aggregates' formation and stabilization. This research may play a key role in converting CFA or opal into artificial soil. The combining of opal with sand to form artificial soil will not only solve the environmental problems caused by large-scale CFA stockpiles but will also enable the comprehensive utilization of siliceous materials in agriculture.


Assuntos
Areia , Dióxido de Silício , Solo/química , Água
5.
Bull Environ Contam Toxicol ; 109(1): 163-168, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35394141

RESUMO

The hydrothermal hydrogen reduction process for treating high-iron bauxite residue (red mud) was investigated, and the optimum conditions of alumina extraction as well as the enrichment of iron minerals were verified by experiments. Results show that the surface magnetization of Al-goethite under the function of hydrogen reduction accelerates its conversion to hematite and/or magnetite. This conversion releases the substituted Al in goethite as well as the undigested gibbsite/boehmite and further enriches the iron content in residue. After hydrothermal hydrogen reduction with H2/Red mud ratio of 0.085 mol/20 g at 270°C for 60 min, the alumina relative recovery ratio reaches 95.40% and the grade of iron (total iron in the form of iron element) in the residue can be enriched to 55.85%. Further, co-processing of the obtained iron-rich residue in the steel industry can achieve a significant reduction of red mud discharge.


Assuntos
Óxido de Alumínio , Hidrogênio , Ferro/química
6.
Bull Environ Contam Toxicol ; 109(1): 20-29, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35088100

RESUMO

Bauxite residue is a highly alkaline waste from alumina refining, and is mainly disposed by stacking with high environmental risks. Here, the migration of alkaline constituents and the restoration evaluation with phosphogypsum were discussed by soil column experiments to investigate the alkaline regulation in bauxite residue disposal areas (BRDAs). The pH, free alkali, exchangeable sodium in the top layer (0-25 cm depth) covered with BR and phosphogypsum mixtures were reduced from 10.89 ± 0.02, 285.45 ± 21.15 mmol/kg, 385.63 ± 30.34 mg/kg to 9.00 ± 0.50, 12.50 ± 1.50 mmol/kg, 97.00 ± 10.50 mg/kg. For the sublayers, including depths of 35, 45, 55 cm, these values dropped to 9.86, 10.06, 10.03; 38.23, 86.12, 148.00 mmol/kg; 152.90, 246.00, 305.00 mg/kg, respectively. These results indicated alkaline indicators for phosphogypsum amended BR declined dramatically, and the parameters for sublayers were also decreased due to the migration of alkaline constituents. The physicochemical properties for amended BR could meet the conditions for plant growth. This research provided a reference for alkalinity regulation in BRDAs by phosphogypsum.


Assuntos
Óxido de Alumínio , Solo , Desenvolvimento Vegetal , Solo/química
7.
J Org Chem ; 86(3): 2965-2973, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33492130

RESUMO

We have developed a protocol for efficient synthesis of indolin-2-ones from benzofuranones and aryl amines using iodine as a mediator. A diverse range of benzofuranones and aryl amines undergo cross-dehydrogenative coupling and amidation of 3-aryl benzofuranones for the cascade reaction to generate products in 24-93% yields. This reaction can be easily scaled-up to give an indolin-2-one in a gram scale. Further chemical manipulation of the products enabled useful transformations of the phenol ring including alkylation, arylation, etc.


Assuntos
Aminas , Indóis , Catálise , Estrutura Molecular
8.
Bioorg Med Chem Lett ; 30(21): 127459, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32784087

RESUMO

We report herein the synthesis of novel ring-fused pyrazoloamino pyridine/pyrimidine derivatives as potential FAK inhibitors and the evaluation of pharmaceutical activity against five cancer cell lines (MDA-MB-231, BXPC-3, NCI-H1975, DU145 and 786O). Generally, the majority of compounds displayed strong anti-FAK enzymatic potencies (IC50 < 1 nM) and could effectively inhibit several class of cancer cell lines within the concentration of 3 µM in comparison with GSK2256098 as a reference. Among them, compound 4o is considered to be the most effective due to high sensitivity in antiproliferation. In culture, 4o could not only inhibit FAK Y397 phosphorylation in MDA-MB-231 cell line, but also trigger apoptosis in a dose-dependent manner. Furthermore, computational docking analysis also suggested that 4o and TAE-226 displayed the similar interaction with FAK kinase domain.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Quinase 1 de Adesão Focal/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Quinase 1 de Adesão Focal/metabolismo , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Piridinas/química , Pirimidinas/química , Relação Estrutura-Atividade
9.
Artigo em Inglês | MEDLINE | ID: mdl-30858202

RESUMO

The quinazolinones are a new class of antibacterials with in vivo efficacy against methicillin-resistant Staphylococcus aureus (MRSA). The quinazolinones target cell wall biosynthesis and have a unique mechanism of action by binding to the allosteric site of penicillin-binding protein 2a (PBP 2a). We investigated the potential for synergism of a lead quinazolinone with several antibiotics of different classes using checkerboard and time-kill assays. The quinazolinone synergized with ß-lactam antibiotics. The combination of the quinazolinone with commercial piperacillin-tazobactam showed bactericidal synergy at sub-MICs of all three drugs. We demonstrated the efficacy of the triple-drug combination in a mouse MRSA neutropenic thigh infection model. The proposed mechanism for the synergistic activity in MRSA involves inhibition of the ß-lactamase by tazobactam, which protects piperacillin from hydrolysis, which can then inhibit its target, PBP 2. Furthermore, the quinazolinone binds to the allosteric site of PBP 2a, triggering the allosteric response. This leads to the opening of the active site, which, in turn, binds another molecule of piperacillin. In other words, PBP 2a, which is not normally inhibited by piperacillin, becomes vulnerable to inhibition in the presence of the quinazolinone. The collective effect is the impairment of cell wall biosynthesis, with bactericidal consequence. Two crystal structures for complexes of the antibiotics with PBP 2a provide support for the proposed mechanism of action.


Assuntos
Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Piperacilina/farmacologia , Quinazolinonas/farmacologia , Tazobactam/farmacologia , Antibacterianos/farmacologia , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana
10.
Biomed Chromatogr ; : e4267, 2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29689635

RESUMO

Curcumin (CUR) is the major active component of turmeric and plays an important role in the prevention and treatment of many chronic diseases such as respiratory and neurodegenerative disease. In the present work, a rapid and simple LC-MS/MS method was developed to investigate the pharmacokinetics and tissue distribution of CUR and its metabolites in mice after intravenous administration of CUR (20 mg/kg). The results showed that the values of AUC0-∞ were 107.0 ± 18.3, 6.0 ± 1.2 and 12.0 ± 4.0 (mg/L) min, and those for t1/2z were 32.4 ± 10.8, 6.4 ± 2.4 and 5.6 ± 1.8 min for CUR, dihydrocurcumin (DHC) and tetrahydrocurcumin (THC) in plasma, respectively. CUR and THC could be detected in liver while CUR and DHC were detected in kidney. Only CUR was detected in brain. These findings indicated that THC was the main metabolite of CUR in plasma. The exposure of CUR in plasma was 6-fold greater than that in liver, kidney and brain.

11.
Cancer Cell Int ; 17: 122, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29296105

RESUMO

BACKGROUND: Patient-derived xenografts (PDX) have a biologically stable in tumor architecture, drug responsiveness, mutational status and global gene-expression patterns. Numerous PDX models have been established to date, however their thorough characterization regarding the tumor formation and rates of tumor growth in the established models remains a challenging task. Our study aimed to provide more detailed information for establishing the PDX models successfully and effectively. METHODS: We transplanted four different types of solid tumors from 108 Chinese patients, including 21 glioblastoma (GBM), 11 lung cancers (LC), 54 gastric cancers (GC) and 21 colorectal cancers (CRC), and took tumor tissues passaged for three successive generations. Here we report the rate of tumor formation, tumor-forming times, tumor growth curves and mortality of mice in PDX model. We also report H&E staining and immunohistochemistry for HLA-A, CD45, Ki67, GFAP, and CEA protein expression between patient cancer tissues and PDX models. RESULTS: Tumor formation rate increased significantly in subsequent tumor generations. Also, the survival rates of GC and CRC were remarkably higher than GBM and LC. As for the time required for the formation of tumors, which reflects the tumor growth rate, indicated that tumor growth rate always increased as the generation number increased. The tumor growth curves also illustrate this law. Similarly, the survival rate of PDX mice gradually improved with the increased generation number in GC and CRC. And generally, there was more proliferation (Ki67+) in the PDX models than in the patient tumors, which was in accordance with the results of tumor growth rate. The histological findings confirm similar histological architecture and degrees of differentiation between patient cancer tissues and PDX models with statistical analysis by GraphPad Prism 5.0. CONCLUSION: We established four different types of PDX models successfully, and our results add to the current understanding of the establishment of PDX models and may contribute to the extension of application of different types of PDX models.

12.
J Org Chem ; 82(18): 9497-9504, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28831800

RESUMO

An effective and practical CuI-catalyzed methodology toward N-alkyl or N-methyl phosphonamides and phosphinamides was herein demonstrated. The transformation took place readily under the oxidative conditions, and plenty of N-alkylated (methylated) amides (30 examples) were successfully furnished in high efficiency (up to 92% yields). Dicumyl peroxide was considered to act either as the oxidant for the alkylation reaction or as methyl donator for the methylation protocol.

13.
J Org Chem ; 82(11): 5810-5818, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28508647

RESUMO

A general and direct N-arylation of sulfonamides and NH-sulfoximines by sodium arylsulfinates through a desulfitative pathway was herein demonstrated. The reaction proceeded with catalytic loadings of Cu(II)-catalysts without any external ligands. And the novel arylation protocol featured for high efficiency (up to 93% yields) and good substituent tolerance (up to 53 examples). Moreover, a plausible reaction mechanism was also discussed.

14.
J Biol Chem ; 289(52): 36101-15, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25371200

RESUMO

Ascl2, a basic helix-loop-helix transcription factor, is a downstream target of WNT signaling that controls the fate of intestinal cryptic stem cells and colon cancer progenitor cells. However, its involvement in colon cancer and downstream molecular events is largely undefined; in particular, the mechanism by which Ascl2 regulates the plasticity of epithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) programs in colon cancer cells remains unknown. In this study, we systematically demonstrate that Ascl2 loss of function in colon cancer cells promotes MET by derepressing the expression of microRNA (miR)-200s (i.e. miR-200b, miR-200a, miR-429, miR-200c, and miR-141) and further activating their expression through a transcriptional mechanism that involves direct binding to the most proximal E-box (E-box2) in the miR-200b-a-429 promoter. Activation of miR-200s due to Ascl2 deficiency led to the inhibition of ZEB1/2 expression and the alteration of epithelial and mesenchymal features. Transfection of miR-200b, miR-200a, and miR-429 inhibitors into Ascl2-deficient colon cancer cells promoted the epithelial-mesenchymal transition in a reversible manner. Transfection of miR-200a or miR-429 inhibitors into Ascl2-deficient colon cancer cells increased cellular proliferation and migration. Ascl2 mRNA levels and the miR-200a, miR-200b, miR-200c, miR-141, or miR-429 levels in the colon cancerous samples were inversely correlated. These results provide the first evidence of a link between Ascl2 and miR-200s in the regulation of EMT-MET plasticity in colon cancer.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Neoplasias do Colo/metabolismo , Transição Epitelial-Mesenquimal , MicroRNAs/genética , Idoso , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HT29 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Metástase Linfática , Masculino , MicroRNAs/biossíntese , Pessoa de Meia-Idade , Família Multigênica , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de Zinco
15.
J Am Chem Soc ; 137(5): 1738-41, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25629446

RESUMO

In the face of the clinical challenge posed by resistant bacteria, the present needs for novel classes of antibiotics are genuine. In silico docking and screening, followed by chemical synthesis of a library of quinazolinones, led to the discovery of (E)-3-(3-carboxyphenyl)-2-(4-cyanostyryl)quinazolin-4(3H)-one (compound 2) as an antibiotic effective in vivo against methicillin-resistant Staphylococcus aureus (MRSA). This antibiotic impairs cell-wall biosynthesis as documented by functional assays, showing binding of 2 to penicillin-binding protein (PBP) 2a. We document that the antibiotic also inhibits PBP1 of S. aureus, indicating a broad targeting of structurally similar PBPs by this antibiotic. This class of antibiotics holds promise in fighting MRSA infections.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas , Quinazolinonas/farmacologia , Antibacterianos/farmacocinética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Disponibilidade Biológica , Testes de Sensibilidade Microbiana , Modelos Moleculares , Proteínas de Ligação às Penicilinas , Conformação Proteica , Quinazolinonas/farmacocinética , Staphylococcus/efeitos dos fármacos
16.
Anal Biochem ; 478: 8-13, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25769418

RESUMO

The aim of this study was to investigate the expression and organ distribution of cytochrome P450 (CYP450) enzymes, microsomal epoxide hydrolase (MEH), and microsomal glutathione-S-transferase (MGST 1, 2, 3) in human liver, lung, intestinal, and kidney microsomes by targeted peptide-based quantification using nano liquid chromatography-tandem multiple reaction monitoring (nano LC-MRM). Applying this method, we analyzed 16 human liver microsomes and pooled lung, kidney, and intestine microsomes. Nine of the CYP450s (CYP1A2, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, 3A4, 3A5) could be quantified in liver. Except for CYP3A4 and 3A5 existing in intestine, other CYP450s had little content (<0.1 pmol/mg protein) in extrahepatic tissues. MEH and MGSTs could be quantified both in hepatic and in extrahepatic tissues. The highest concentrations of MEH and MGST 1, 2 were found in liver; conversely MGST 3 was abundant in human kidney and intestine compared to liver. The targeted proteomics assay described here can be broadly and efficiently utilized as a tool for investigating the targeted proteins. The method also provides novel CYP450s, MEH, and MGSTs expression data in human hepatic and extrahepatic tissues that will benefit rational approaches to evaluate metabolism in drug development.


Assuntos
Sistema Enzimático do Citocromo P-450/análise , Epóxido Hidrolases/análise , Glutationa Transferase/análise , Microssomos Hepáticos/enzimologia , Sequência de Aminoácidos , Cromatografia Líquida/métodos , Ensaios Enzimáticos/métodos , Humanos , Intestinos/enzimologia , Rim/enzimologia , Pulmão/enzimologia , Dados de Sequência Molecular , Espectrometria de Massas em Tandem/métodos
17.
Dig Dis Sci ; 60(7): 1977-90, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25701318

RESUMO

BACKGROUND AND AIM: The roles of host glycosylation in interactions with EPEC and EHEC O157:H7 are largely unclear; this study examined whether O-glycans are involved in EPEC and EHEC O157:H7 adherence to HT-29 cells. METHODS: Bacterial adherence to the cultured cells was determined using the direct co-staining of adherent bacteria and host cells, the adherent bacteria plating, and/or the direct fluorescent observation of the adherent GFP-labeled bacteria. RESULTS: A comparison of the adherence of EPEC and EHEC O157:H7 to HT-29-Gal and HT-29 cells indicated that the differentiation of HT-29 cells led to a reduction in the adherence of EPEC and EHEC O157:H7. EPEC and EHEC O157:H7 adhesion decreased after the abrogation of O-glycan biosynthesis mediated by benzyl-α-GalNAc treatment. Core 2 O-glycan-deficient HT-29 cells induced by C2GnT2 knockdown had a significant reduction in EPEC and EHEC O157:H7 adhesion in C2GnT2-sh2/HT-29 cells compared with HT-29 and shRNA-Ctr/HT-29 cells. MUC2 expression in benzyl-α-GalNAc-treated HT-29 cells was significantly reduced but unchanged in C2GnT2-deficient HT-29 cells. EPEC or EHEC O157:H7 infection in C2GnT2-deficient HT-29 cells deteriorated the epithelial barrier function. The occludin expression in the shRNA-Ctr/HT-29 and C2GnT2-sh2/HT-29 cells after infection with EPEC or EHEC O157:H7 was pyknic and discontinuous at the cell surface compared with its continuous distribution of control cells. These data indicate that EPEC and EHEC O157:H7 adherence to HT-29 cells is related to mucin-type core 2 O-glycan. CONCLUSIONS: This study provides the concepts toward the design of carbohydrate-dependent inhibition of EPEC and EHEC O157:H7 adhesion to human intestinal epithelial cells.


Assuntos
Aderência Bacteriana/fisiologia , Escherichia coli Êntero-Hemorrágica/metabolismo , Escherichia coli Enteropatogênica/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Acetilgalactosamina/análogos & derivados , Acetilgalactosamina/farmacologia , Anticorpos , Compostos de Benzil/farmacologia , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Enteropatogênica/genética , Células HT29 , Humanos , Mucina-2/genética , Mucina-2/metabolismo , N-Acetilglucosaminiltransferases/genética , Interferência de RNA
18.
J Biol Chem ; 288(8): 5407-16, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23316049

RESUMO

We investigated whether a synthetic tetrameric branched peptide based on the conserved TFLK motif from mammary-associated serum amyloid A3 (M-SAA3) is more efficient than the monomeric peptide at up-regulating MUC3 expression and examined the possible mechanism(s) and biological significance of this process. We used standard solid-phase methods to synthesize a tetrameric branched peptide (sequence GWLTFLKAAG) containing a trilysine core, termed the TFLK-containing 10-mer BP. The aberrant expression of transcription factors was analyzed using a transcription factor protein/DNA array. MUC3 and relevant transcription factors were detected using real-time PCR and/or Western blots. The luciferase assay, EMSA, and ChIP assays were used to analyze the activity of the human MUC3 promoter. The bacterial adherence assay was used to evaluate the in vitro inhibition of enteropathogenic Escherichia coli or enterohemorrhage E. coli serotype O157:H7 (EHEC O157:H7) adherence to HT-29-Gal cells after treatment with the TFLK-containing 10-mer BP. In HT-29-Gal cells, the TFLK-containing 10-mer BP induced higher levels of MUC3 expression than the M-SAA3-derived N-terminal 10-mer monomeric peptide, and MUC3 expression was activated through transcriptional mechanisms, including the induction of multiple transcription factors and further binding with their cis-elements between nucleotides -242 and -62 within MUC3 promoter. Interestingly, the TFLK-containing 10-mer BP dramatically inhibited enteropathogenic E. coli and EHEC O157:H7 adherence to the HT-29-Gal cells compared with the controls. This finding suggests a potential therapeutic use for this peptide to prevent gastrointestinal infection.


Assuntos
Regulação da Expressão Gênica , Mucina-3/biossíntese , Mucina-3/fisiologia , Peptídeos/química , Motivos de Aminoácidos , Aderência Bacteriana , Escherichia coli/metabolismo , Escherichia coli O157/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Células HT29 , Humanos , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Transcrição Gênica
19.
J Am Chem Soc ; 136(9): 3664-72, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24517363

RESUMO

Infections caused by hard-to-treat methicillin-resistant Staphylococcus aureus (MRSA) are a serious global public-health concern, as MRSA has become broadly resistant to many classes of antibiotics. We disclose herein the discovery of a new class of non-ß-lactam antibiotics, the oxadiazoles, which inhibit penicillin-binding protein 2a (PBP2a) of MRSA. The oxadiazoles show bactericidal activity against vancomycin- and linezolid-resistant MRSA and other Gram-positive bacterial strains, in vivo efficacy in a mouse model of infection, and have 100% oral bioavailability.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas , Bactérias Gram-Positivas/efeitos dos fármacos , Oxidiazóis/farmacologia , Proteínas de Ligação às Penicilinas/antagonistas & inibidores , beta-Lactamas/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacocinética , Disponibilidade Biológica , Parede Celular/efeitos dos fármacos , Simulação por Computador , Bactérias Gram-Positivas/citologia , Bactérias Gram-Positivas/metabolismo , Staphylococcus aureus Resistente à Meticilina/citologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Oxidiazóis/química , Oxidiazóis/farmacocinética , Proteínas de Ligação às Penicilinas/química , Conformação Proteica , beta-Lactamas/química , beta-Lactamas/farmacocinética
20.
Exp Cell Res ; 319(20): 3214-25, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23872314

RESUMO

Numb is highly expressed throughout the crypt-villus axis of intestinal mucosa and functions as cell fate determinant and integrator of cell-to-cell adhesion. Increased paracellular permeability of intestinal epithelial cells is associated with the epithelial barrier dysfunction of inflammatory bowel diseases (IBDs). The apical junctional complex (AJC) assembly and myosin light chain (MLC) phosphorylation regulate adherens junctions (AJ) and tight junctions (TJ). We determined whether and how Numb modulate the paracellular permeability of intestinal epithelial cells. Caco-2 intestinal epithelial cells and their Numb-interfered counterparts were used in the study for physiological, morphological and biological analyses. Numb, expressed in intestinal epithelial cells and located at the plasma membrane of Caco-2 cells in a basolateral to apical distribution, increased in the intestinal epithelial cells with the formation of the intestinal epithelial barrier. Numb expression decreased and accumulated in the cytoplasm of intestinal epithelial cells in a DSS-induced colitis mouse model. Numb co-localized with E-cadherin, ZO-1 and Par3 at the plasma membrane and interacted with E-cadherin and Par3. Knockdown of Numb in Caco-2 cells altered the F-actin structure during the Ca(2+) switch assay, enhanced TNFα-/INF-γ-induced intestinal epithelial barrier dysfunction and TJ destruction, and increased the Claudin-2 protein level. Immunofluorescence experiments revealed that NMIIA and F-actin co-localized at the cell surface of Caco-2 cells. Numb knockdown in Caco-2 cells increased F-actin contraction and the abundance of phosphorylated MLC. Numb modulated the intestinal epithelial barrier in a Notch signaling-independent manner. These findings suggest that Numb modulates the paracellular permeability by affecting AJC assembly and MLC phosphorylation.


Assuntos
Permeabilidade da Membrana Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Intestino Delgado/citologia , Proteínas de Membrana/metabolismo , Cadeias Leves de Miosina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Junções Íntimas/metabolismo , Células CACO-2 , Humanos , Fosforilação , Células Tumorais Cultivadas
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