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1.
Biochem Biophys Res Commun ; 732: 150409, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39033550

RESUMO

INTRODUCTION: WNT1-inducible signalling pathway protein 1 (WISP1) promotes progression of several tumor entities often correlating with worse prognosis. Here its expression regulation and role in the progression of chronic liver diseases (CLD) was investigated. METHODS: WISP1 expression was analyzed in human HCC datasets, in biopsies and serum samples and an HCC patient tissue microarray (TMA) including correlation to clinicopathological parameters. Spatial distribution of WISP1 expression was determined using RNAscope analysis. Regulation of WISP1 expression was investigated in cytokine-stimulated primary mouse hepatocytes (PMH) by array analysis and qRT-PCR. Outcome of WISP1 stimulation was analyzed by IncuCyte S3-live cell imaging, qRT-PCR, and immunoblotting in murine AML12 cells. RESULTS: In a TMA, high WISP1 expression was positively correlated with early HCC stages and male sex. Highest WISP1 expression levels were detected in patients with cirrhosis as compared to healthy individuals, patients with early fibrosis, and non-cirrhotic HCC in liver biopsies, expression datasets and serum samples. WISP1 transcripts were predominantly detected in hepatocytes of cirrhotic rather than tumorous liver tissue. High WISP1 expression was associated with better survival. In PMH, AML12 and HepaRG, WISP1 was identified as a specific TGF-ß1 target gene. Accordingly, expression levels of both cytokines positively correlated in human HCC patient samples. WISP1-stimulation induced the expression of Bcl-xL, PCNA and p21 in AML12 cells. CONCLUSIONS: WISP1 expression is induced by TGF-ß1 in hepatocytes and is associated with cirrhotic liver disease. We propose a crucial role of WISP1 in balancing pro- and anti-tumorigenic effects during premalignant stages of CLD.

2.
Glob Chang Biol ; 30(7): e17427, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39021313

RESUMO

Atmospheric nitrogen (N) deposition in forests can affect soil microbial growth and turnover directly through increasing N availability and indirectly through altering plant-derived carbon (C) availability for microbes. This impacts microbial residues (i.e., amino sugars), a major component of soil organic carbon (SOC). Previous studies in forests have so far focused on the impact of understory N addition on microbes and microbial residues, but the effect of N deposition through plant canopy, the major pathway of N deposition in nature, has not been explicitly explored. In this study, we investigated whether and how the quantities (25 and 50 kg N ha-1 year-1) and modes (canopy and understory) of N addition affect soil microbial residues in a temperate broadleaf forest under 10-year N additions. Our results showed that N addition enhanced the concentrations of soil amino sugars and microbial residual C (MRC) but not their relative contributions to SOC, and this effect on amino sugars and MRC was closely related to the quantities and modes of N addition. In the topsoil, high-N addition significantly increased the concentrations of amino sugars and MRC, regardless of the N addition mode. In the subsoil, only canopy N addition positively affected amino sugars and MRC, implying that the indirect pathway via plants plays a more important role. Neither canopy nor understory N addition significantly affected soil microbial biomass (as represented by phospholipid fatty acids), community composition and activity, suggesting that enhanced microbial residues under N deposition likely stem from increased microbial turnover. These findings indicate that understory N addition may underestimate the impact of N deposition on microbial residues and SOC, highlighting that the processes of canopy N uptake and plant-derived C availability to microbes should be taken into consideration when predicting the impact of N deposition on the C sequestration in temperate forests.


Assuntos
Carbono , Florestas , Nitrogênio , Microbiologia do Solo , Solo , Nitrogênio/metabolismo , Carbono/metabolismo , Carbono/análise , Solo/química , Amino Açúcares/metabolismo , Amino Açúcares/análise , Árvores/crescimento & desenvolvimento , Árvores/metabolismo
3.
Antonie Van Leeuwenhoek ; 117(1): 102, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012584

RESUMO

This study represents the first analysis of the bacterial community in chickens affected by swollen head syndrome, utilizing 16S rRNA gene sequencing. Samples were obtained from clinical laying chickens and were examined for the presence of Avibacterium paragallinarum (APG) and Ornithobacterium rhinotracheale (ORT) using conventional polymerase chain reaction (PCR). From the samples, five APG-positive (APG) and APG-negative (N-APG) samples were chosen, along with five specific pathogen-free chickens, for 16S rRNA gene sequencing. Results showed that APG and ORT were widely detected in the chicken samples with swollen head syndrome (SHS, 9/10), while APG was detected in all five specific pathogen-free (SPF) samples. In contrast, conventional PCR sensitivity was found to be inadequate for diagnosis, with only 35.7% (5/14) and 11.1% (1/9) sensitivity for APG and ORT, respectively, based on 16S rRNA gene sequencing data. Furthermore, 16S rRNA gene sequencing was able to quantify the bacteria in the samples, revealing that the relative abundance of APG in the APG group ranged from 2.7 to 81.3%, while the relative abundance of APG in the N-APG group ranged from 0.1 to 21.0%. Notably, a low level of APG was also detected in all 5 SPF samples. The study also identified a significant number of animal and human common bacterial pathogens, including but not limited to Gallibacterium anatis, Riemerella columbina, Enterococcus cecorum, Mycoplasma synoviae, Helicobacter hepaticus, and Staphylococcus lentus. In conclusion, 16S rRNA gene sequencing is a valuable tool for bacterial pathogen diagnosis and the discovery of novel bacterial pathogens, while conventional PCR is not reliable for diagnosis.


Assuntos
Galinhas , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas , RNA Ribossômico 16S , RNA Ribossômico 16S/genética , Animais , Galinhas/microbiologia , Reação em Cadeia da Polimerase/métodos , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/diagnóstico , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , DNA Bacteriano/genética , Análise de Sequência de DNA , Filogenia
4.
Circ Res ; 127(10): 1221-1232, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-32791884

RESUMO

RATIONALE: Endothelial cells are thought to emerge de novo from the mesoderm to form the entire circulatory system. Recently, erythro-myeloid progenitors (EMPs) have been proposed to be another remarkable developmental origin for blood vessels in multiple organs, including the hindbrain, liver, lung, and heart, as demonstrated by lineage tracing studies using different genetic tools. These observations challenge the current consensus that intraembryonic vessels are thought to expand solely by the proliferation of preexisting endothelial cells. Resolution of this controversy over the developmental origin of endothelial cells is crucial for developing future therapeutics for vessel-dependent organ repair and regeneration. OBJECTIVE: To examine the contribution of EMPs to intraembryonic endothelial cells. METHODS AND RESULTS: We first used a transgenic mouse expressing a tamoxifen-inducible Mer-iCre fusion protein driven by the Csf1r (colony stimulating factor 1 receptor) promoter. Genetic lineage tracing based on Csf1r-Mer-iCre-Mer showed no contribution of EMPs to brain endothelial cells identified by several markers. We also generated a knock-in mouse line by inserting an internal ribosome entry site-iCre cassette into the 3' untranslated region of Csf1r gene to further investigate the cellular fates of EMPs. Similarly, we did not find any Csf1r-ires-iCre traced endothelial cells in brain, liver, lung, or heart in development either. Additionally, we found that Kit (KIT proto-oncogene receptor tyrosine kinase) was expressed not only in EMPs but also in embryonic hindbrain endothelial cells. Therefore, Kit promoter-driven recombinase, such as Kit-CreER, is a flawed tool for lineage tracing when examining the contribution of EMPs to hindbrain endothelial cells. We also traced CD45 (protein tyrosine phosphatase receptor type C; Ptprc)+ circulating EMPs and did not find any CD45 lineage-derived endothelial cells during development. CONCLUSIONS: Our study suggested that EMPs are not the origin of intraembryonic endothelial cells.


Assuntos
Linhagem da Célula , Células Endoteliais/citologia , Células Precursoras Eritroides/citologia , Animais , Endotélio Vascular/citologia , Endotélio Vascular/embriologia , Coração Fetal/citologia , Fígado/citologia , Fígado/embriologia , Pulmão/citologia , Pulmão/embriologia , Macrófagos/citologia , Mesoderma/citologia , Camundongos , Rombencéfalo/citologia , Rombencéfalo/embriologia
5.
J Org Chem ; 87(2): 1272-1284, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34964642

RESUMO

Inspired by Roush's pioneering work on rare sugars, we have developed a scalable, stereoselective, de novo synthesis of orthogonally protected C2-fluoro digitoxose and cymarose, utilizing Sharpless kinetic resolution and organocatalytic fluorination as key steps. The utility of this strategy is demonstrated by the synthesis of a fluorinated analogue of digoxin, which indicates the fluorine on the sugar ring may have a significant impact on biological activity.


Assuntos
Digoxina , Flúor , Halogenação , Hexoses , Estereoisomerismo
6.
Microb Pathog ; 159: 105145, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34411653

RESUMO

Pasteurella multocida (P. multocida) is a Gram-negative bacterium which causes diseases in poultry, livestock, and humans, resulting in huge economic losses. P. multocida serovar A CQ6 (PmCQ6) is a naturally occurring attenuated strain with a thin capsule. Thus, we aimed to explore why this strain is less virulent and produces less capsule compared with P. multocida serovar A strain CQ2 (PmCQ2). Analysis of capsular polysaccharide synthesis genes in PmCQ6 revealed that, compared with PmCQ2, there was only a single point mutation in the initiation codon sequence of the hyaC gene. To test whether this point mutation caused capsular deficiency and reduced virulence, we rescued this hyaC mutation and observed a restoration of capsule production and higher virulence. Transcriptome analysis showed that the hyaC point mutation led to a downregulation of capsule synthesis and/or iron utilization related-genes. Taken together, the results indicate that the start codon mutation of hyaC is an important factor affecting the capsule synthesis and virulence of PmCQ6.


Assuntos
Infecções por Pasteurella , Pasteurella multocida , Uridina Difosfato Glucose Desidrogenase/genética , Humanos , Infecções por Pasteurella/veterinária , Pasteurella multocida/enzimologia , Pasteurella multocida/genética , Mutação Puntual , Sorogrupo , Virulência/genética
7.
J Biol Chem ; 294(22): 8894-8906, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31010826

RESUMO

Early embryonic endocardium undergoes endothelial-to-mesenchymal transition to form cardiac cushion mesenchymal cells (MCs). Embryonic endocardium also gives rise to fibroblasts, intramyocardial adipocytes, and coronary mural cells, including smooth muscle cells and pericytes, in development. Whether endocardial cells directly differentiate into fibroblasts, coronary mural cells, and adipocytes or indirectly via an intermediate stage of endocardial-derived cushion MCs remains unknown. In addition to endocardium, epicardium and neural crest also contribute to cardiac cushion MCs. Given the developmental heterogeneity of cushion MCs and the lack of specific markers for endocardial-derived cushion MCs, conventional genetic lineage tracing utilizing Cre recombinase driven by one specific regulatory element is not sufficient to examine the fates of endocardial-derived cushion MCs. Intersectional genetic targeting approaches, which combine regulatory elements from two or more genes, have been employed to increase the specificity of cell targeting. Here, we developed a dual-recombinase intersectional targeting approach using Nfatc1-Dre, Sox9-CreER, and Cre/Dre double-dependent reporter Ai66 to specifically label endocardial-derived cushion MCs. Taking advantage of intersectional lineage tracing, we found that a subset of cardiac cells including fibroblasts, coronary mural cells, and intramyocardial adipocytes in adult hearts were derived from endocardial-derived cushion MCs. Our study suggests that embryonic endocardium contributes to cushion MCs first, and then endocardial-derived cushion MCs migrate into myocardium and differentiate into fibroblasts, coronary mural cells, and adipocytes in development. Understanding developmental origins of cardiac cell lineages will provide us more insights into cardiac development, regeneration, and diseases.


Assuntos
Adipócitos/citologia , Linhagem da Célula , Endocárdio/citologia , Células Endoteliais/citologia , Fibroblastos/citologia , Células-Tronco Mesenquimais/citologia , Adipócitos/metabolismo , Animais , Diferenciação Celular , Movimento Celular , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Miocárdio/metabolismo , Miocárdio/patologia , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo
8.
Inorg Chem ; 59(24): 17826-17833, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33296600

RESUMO

Pt(II) photosensitizers are emerging as novel Pt anticancer agents for cancer photodynamic therapy (PDT) to avoid uncontrollable toxicity of cisplatin. However, the application of Pt(II) photosensitizers is limited by tumor hypoxia and the poor penetration depth of excitation light. To overcome these drawbacks, exploiting the next generation of Pt anticancer agents is of urgent need. According to theoretical calculations, novel near-infrared (NIR)-absorbing Pt(II)-chelated azadipyrromethene dyes (PtDP-X, where X = N, C, and S) were designed. Importantly, spin-orbit coupling of the Pt atom could promote the intersystem crossing of a singlet-to-triplet transition for converting oxygen to singlet oxygen (1O2), and the azadipyrromethene skeleton could provide a strong photothermal effect. As expected, PtDP-X exhibited intense NIR absorption and synergistic PDT and photothermal effects with low dark cytotoxicity. Furthermore, water-soluble and biocompatible PtDP-N nanoparticles (PtDP-N NPs) were prepared that achieved effective tumor cell elimination with low side effects under 730 nm light irradiation in vitro and in vivo. This pioneering work could push the exploitation of NIR-absorbing metal-chelated azadipyrromethene dyes, so as to promote the positive evolution of phototherapy agents.


Assuntos
Fármacos Fotossensibilizantes/síntese química , Compostos de Platina/síntese química , Compostos de Platina/farmacologia , Porfobilinogênio/análogos & derivados , Furanos , Células HeLa , Humanos , Raios Infravermelhos , Estrutura Molecular , Fármacos Fotossensibilizantes/química , Fototerapia , Compostos de Platina/química , Porfobilinogênio/química , Espectrofotometria Infravermelho
9.
Appl Opt ; 59(8): 2386-2392, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32225772

RESUMO

In this paper, the self-mixing interference subject to weak optical feedback has been used to measure the damping vibration. By analyzing the spectrum of the signal, the damping coefficient can be extracted precisely from the nth-order Bessel functions, which are determined by the dominant harmonic order of the frequency spectrum. Theoretical derivation and signal processing are presented. Four kinds of vibrating targets with different damping coefficients are measured. Experimental results show that standard deviation and root mean square error of data are less than 0.2 and 0.1, respectively, which means fitted values are stable as well as having a very high fitting precision.

10.
Molecules ; 25(20)2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33076390

RESUMO

Organic modified kaolinite-urea intercalation complex (KUIC) was prepared using dimethyl sulfoxide (DMSO) as the precursor of kaolinite intercalation. Its structure was characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). Subsequently, as a synergistic agent, KUIC was combined with flame retardant ammonium polyphosphate (APP) to improve the flame retardant and smoke suppression performance of unsaturated polyester (UP) resin. A cone calorimeter (CONE) was used to study its flame retardancy and smoke suppression, and a scanning electron microscope (SEM) and thermogravimetry (TG) were used to study the micro morphology of the char and flame retardant mechanism. The results show that 12 phr of APP and 3 phr of KUIC were doped into UP to obtain a 28.0% limiting oxygen index (LOI) value. Compared with UP, the heat release rate and smoke production of UP/APP/KUIC composites were greatly decreased. Meanwhile, KUIC indeed enhanced the mechanical properties of UP.


Assuntos
Retardadores de Chama , Caulim/química , Poliésteres/química , Ureia/química , Compostos de Amônio/química , Polifosfatos/química , Termogravimetria
11.
Org Biomol Chem ; 16(47): 9211-9217, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30468229

RESUMO

The transformation of hydroximoyl fluorides to nitrile oxides for [3 + 2]-cycloaddition with alkynes has been achieved for the first time. The hydroximoyl fluorides used in this work appeared to be not stable, which was proved by a series of experiments. A DFT calculation was performed to better understand the properties of hydroximoyl fluorides. Although not stable, the hydroximoyl fluorides could be successfully converted to the corresponding nitrile oxides for in situ [3 + 2]-cycloaddition with alkynes to yield the isoxazoles. Furthermore, it was feasible to conduct [3 + 2]-cycloaddition reaction without purification after the synthesis of hydroximoyl fluorides from gem-difluoroalkenes. By investigating a class of interesting yet previously rarely explored fluorinated compounds, this work sheds new light on the stability and reactivity of a C-F bond on a C[double bond, length as m-dash]N double bond.

12.
J Biol Chem ; 291(25): 13160-74, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27129231

RESUMO

The hepatic hormone hepcidin is the master regulator of systemic iron homeostasis. Its expression level is adjusted to alterations in iron levels, inflammatory cues, and iron requirements for erythropoiesis. Bone morphogenetic protein 6 (BMP6) contributes to the iron-dependent control of hepcidin. In addition, TGF-ß1 may stimulate hepcidin mRNA expression in murine hepatocytes and human leukocytes. However, receptors and downstream signaling proteins involved in TGF-ß1-induced hepcidin expression are still unclear. Here we show that TGF-ß1 treatment of mouse and human hepatocytes, as well as ectopic expression of TGF-ß1 in mice, increases hepcidin mRNA levels. The hepcidin response to TGF-ß1 depends on functional TGF-ß1 type I receptor (ALK5) and TGF-ß1 type II receptor (TßRII) and is mediated by a noncanonical mechanism that involves Smad1/5/8 phosphorylation. Interestingly, increasing availability of canonical Smad2/3 decreases TGF-ß1-induced hepcidin regulation, whereas the BMP6-hepcidin signal was enhanced, indicating a signaling component stoichiometry-dependent cross-talk between the two pathways. Although ALK2/3-dependent hepcidin activation by BMP6 can be modulated by each of the three hemochromatosis-associated proteins: HJV (hemojuvelin), HFE (hemochromatosis protein), and TfR2 (transferrin receptor 2), these proteins do not control the ALK5-mediated hepcidin response to TGF-ß1. TGF-ß1 mRNA levels are increased in mouse models of iron overload, indicating that TGF-ß1 may contribute to hepcidin synthesis under these conditions. In conclusion, these data demonstrate that a complex regulatory network involving TGF-ß1 and BMP6 may control the sensing of systemic and/or hepatic iron levels.


Assuntos
Hepatócitos/metabolismo , Hepcidinas/genética , Fator de Crescimento Transformador beta1/fisiologia , Animais , Proteína Morfogenética Óssea 6/metabolismo , Células Cultivadas , Feminino , Expressão Gênica , Hepcidinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Ativação Transcricional
13.
Am J Pathol ; 186(7): 1874-1889, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27171900

RESUMO

Disrupting Notch signaling ameliorates experimental liver fibrosis. However, the role of individual Notch ligands in liver damage is unknown. We investigated the effects of Delta-like ligand 4 (Dll4) in liver disease. DLL4 expression was measured in 31 human liver tissues by immunohistochemistry. Dll4 function was examined in carbon tetrachloride- and bile duct ligation-challenged mouse models in vivo and evaluated in hepatic stellate cells, hepatocytes, and Kupffer cells in vitro. DLL4 was expressed in patients' Kupffer and liver sinusoidal endothelial cells. Recombinant Dll4 protein (rDll4) ameliorated hepatocyte apoptosis, inflammation, and fibrosis in mice after carbon tetrachloride challenge. In vitro, rDll4 significantly decreased lipopolysaccharide-dependent chemokine expression in both Kupffer and hepatic stellate cells. In bile duct ligation mice, rDll4 induced massive hepatic necrosis, resulting in the death of all animals within 1 week. Inflammatory cell infiltration and chemokine ligand 2 (Ccl2) expression were significantly reduced in rDll4-receiving bile duct ligation mice. Recombinant Ccl2 rescued bile duct ligation mice from rDll4-mediated death. In patients with acute-on-chronic liver failure, DLL4 expression was inversely associated with CCL2 abundance. Mechanistically, Dll4 regulated Ccl2 expression via NF-κB. Taken together, Dll4 modulates liver inflammatory response by down-regulating chemokine expression. rDll4 application results in opposing outcomes in two models of liver damage. Loss of DLL4 may be associated with CCL2-mediated cytokine storm in patients with acute-on-chronic liver failure.


Assuntos
Quimiocinas/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Hepatopatias/patologia , Proteínas de Membrana/metabolismo , Animais , Western Blotting , Quimiocina CCL2/biossíntese , Regulação para Baixo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Hepatopatias/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real
14.
Arch Virol ; 162(12): 3611-3618, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28803371

RESUMO

Porcine epidemic diarrhea virus (PEDV) is a causative agent of porcine intestinal disease, which causes vomiting, diarrhea, and dehydration in piglets. PEDV is associated with the most severe pathogenesis in one-week-old piglets, with mortality rates reaching 100%. A PEDV strain was isolated from the intestinal tract of diarrheic piglets from a pig farm in Jiangsu Province in March 2016, termed the JS201603 isolate. The isolated virus was confirmed to be PEDV via RT-PCR, electron microscopy, a cytopathic effect assay and sequence analysis. The S and ORF3 genes of the JS201603 isolate were sequenced, revealing that the S gene was associated with a 15-base insertion at 167 nt, 176 - 186 nt, and 427 - 429 nt, as well as a six-base deletion in 487 - 492 nt, indicating that it was a current epidemic variant compared with the classical strain, CV777. No deletion occurred between 245 - 293 nt of the ORF3 gene in the JS201603 isolate compared with the vaccine isolates YY2013 and SQ2014. An experimental infection model indicated that the piglets in the challenge group successively developed diarrhea, exhibiting yellow-colored loose stools with a foul odor. The piglets in the JS201603 isolate challenge group displayed reduced food consumption, lost weight, and in severe cases even died. No abnormalities were observed in the control group. The JS201603 variant isolated in this study contributes to the evolutionary analysis of diarrhea virus. The experimental infection model has established a foundation for further studies on vaccine development.


Assuntos
Infecções por Coronavirus/veterinária , Diarreia/veterinária , Genótipo , Vírus da Diarreia Epidêmica Suína/classificação , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Doenças dos Suínos/patologia , Doenças dos Suínos/virologia , Animais , China , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Efeito Citopatogênico Viral , Diarreia/patologia , Diarreia/virologia , Microscopia Eletrônica de Transmissão , Mutação , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/patogenicidade , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Suínos , Proteínas Virais/genética , Vírion/ultraestrutura , Virulência
15.
FASEB J ; 29(2): 724-32, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25384421

RESUMO

Hippo signaling pathway is emerging as a novel target for anticancer therapy because it plays key roles in organ size control and tumorigenesis. As the downstream effectors, Yes-associated protein (YAP)-transcriptional enhancer activation domain family member (TEAD) association is essential for YAP-driven oncogenic activity, while TEAD is largely dispensable for normal tissue growth. We present the design of YAP-like peptides (17mer) to occupy the interface 3 on TEAD. Introducing cysteines at YAP sites 87 and 96 can induce disulfide formation, as confirmed by crystallography. The engineered peptide significantly improves the potency in disrupting YAP-TEAD interaction in vitro. To confirm that blocking YAP-TEAD complex formation by directly targeting on TEAD is a valid approach, we report a significant reduction in tumor growth rate in a hepatocellular carcinoma xenograft model after introducing the dominant-negative mutation (Y406H) of TEAD1 to abolish YAP-TEAD interaction. Our results suggest that targeting TEAD is a promising strategy against YAP-induced oncogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Animais , Ligação Competitiva , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Clonagem Molecular , Cristalografia por Raios X , Cisteína/química , Dissulfetos , Feminino , Glutationa Transferase/metabolismo , Via de Sinalização Hippo , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Transplante de Neoplasias , Peptídeos/química , Peptídeos Cíclicos/química , Ligação Proteica , Estrutura Terciária de Proteína , Transdução de Sinais , Ressonância de Plasmônio de Superfície , Fatores de Transcrição de Domínio TEA , Proteínas de Sinalização YAP
16.
Yao Xue Xue Bao ; 51(9): 1436-40, 2016 09.
Artigo em Chinês | MEDLINE | ID: mdl-29924535

RESUMO

Alzheimer's disease (AD) is a degenerative disease of the nervous system. Compound I reported to have inhibitory activity on AChE was used as a lead compound in this study, and 4-pyridinylthiazole-2-amines were designed by optimizing compound I structure. The new compounds were synthesized from acetylpyridines through five-steps of reaction, and their inhibition activities on AChE were measured in vitro by Ellman method. The new compounds exhibited a clear inhibitory activity on AChE in vitro. The bioactivity of compound 13c was the best among them, and its IC(50) value was 0.15 µmol·L(-1), which was better than that of rivastigmine and compound I in the control. Meanwhile, it exhibited little inhibition on butyrylcholinesterase. So the selective inhibitory activities of 4-pyridinylthiazole-2-amines to acetylcholinesterase were worth of studying furtherly.


Assuntos
Aminas/farmacologia , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Acetilcolinesterase , Doença de Alzheimer , Aminas/síntese química , Butirilcolinesterase , Inibidores da Colinesterase/síntese química , Rivastigmina , Relação Estrutura-Atividade
18.
Clin Sci (Lond) ; 128(11): 761-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25602745

RESUMO

Transforming growth factor ß (TGF-ß) is cytostatic towards damage-induced compensatory hepatocyte proliferation. This function is frequently lost during hepatocarcinogenesis, thereby switching the TGF-ß role from tumour suppressor to tumour promoter. In the present study, we investigate Smad7 overexpression as a pathophysiological mechanism for cytostatic TGF-ß inhibition in liver damage and hepatocellular carcinoma (HCC). Transgenic hepatocyte-specific Smad7 overexpression in damaged liver of fumarylacetoacetate hydrolase (FAH)-deficient mice increased compensatory proliferation of hepatocytes. Similarly, modulation of Smad7 expression changed the sensitivity of Huh7, FLC-4, HLE and HLF HCC cell lines for cytostatic TGF-ß effects. In our cohort of 140 HCC patients, Smad7 transcripts were elevated in 41.4% of HCC samples as compared with adjacent tissue, with significant positive correlation to tumour size, whereas low Smad7 expression levels were significantly associated with worse clinical outcome. Univariate and multivariate analyses indicate Smad7 levels as an independent predictor for overall (P<0.001) and disease-free survival (P=0.0123). Delineating a mechanism for Smad7 transcriptional regulation in HCC, we identified cold-shock Y-box protein-1 (YB-1), a multifunctional transcription factor. YB-1 RNAi reduced TGF-ß-induced and endogenous Smad7 expression in Huh7 and FLC-4 cells respectively. YB-1 and Smad7 mRNA expression levels correlated positively (P<0.0001). Furthermore, nuclear co-localization of Smad7 and YB-1 proteins was present in cancer cells of those patients. In summary, the present study provides a YB-1/Smad7-mediated mechanism that interferes with anti-proliferative/tumour-suppressive TGF-ß actions in a subgroup of HCC cells that may facilitate aspects of tumour progression.


Assuntos
Carcinoma Hepatocelular/genética , Proliferação de Células , Hepatócitos/metabolismo , Hepatopatias/genética , Neoplasias Hepáticas/genética , Proteína Smad7/genética , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Hepatopatias/metabolismo , Hepatopatias/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos da Linhagem 129 , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Pessoa de Meia-Idade , Análise Multivariada , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Smad7/metabolismo , Análise de Sobrevida , Fator de Crescimento Transformador beta/farmacologia , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismo
20.
Mol Cancer Ther ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39087485

RESUMO

KRAS is the most frequently dysregulated oncogene with high prevalence in NSCLC, colorectal cancer, and pancreatic cancer. FDA-approved sotorasib and adagrasib provide breakthrough therapies for cancer patients with KRASG12C mutation. However, there is still high unmet medical need for new agents targeting broader KRAS-driven tumors. An emerging and promising opportunity is to develop a pan KRAS inhibitor by suppressing the upstream protein SOS1. SOS1 is a key activator of KRAS and facilitates the conversion of GDP-bound KRAS state to GTP-bound KRAS state. Binding to its catalytic domain, small molecule SOS1 inhibitor has demonstrated the ability to suppress KRAS activation and cancer cell proliferation. RGT-018, a potent and selective SOS1 inhibitor, was identified with optimal drug-like properties. In vitro, RGT-018 blocked the interaction of KRAS:SOS1 with single digit nM potency and is highly selective against SOS2. RGT-018 inhibited KRAS signaling and the proliferation of a broad spectrum of KRAS-driven cancer cells as a single agent in vitro. Further enhanced anti-proliferation activity was observed when RGT-018 was combined with MEK, KRASG12C, EGFR or CDK4/6 inhibitors. Oral administration of RGT-018 inhibited tumor growth and suppressed KRAS signaling in tumor xenografts in vivo. Combination with MEK or KRASG12C inhibitors led to significant tumor regression. Furthermore, RGT-018 overcame the resistance to the approved KRASG12C inhibitors caused by clinically acquired KRAS mutations either as a single agent or in combination. RGT-018 displayed promising pharmacological properties for combination with targeted agents to treat a broader KRAS-driven patient population.

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