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BACKGROUND: The chromatin-remodeling enzymes BRG1 (brahma-related gene 1) and CHD4 (chromodomain helicase DNA-binding protein 4) independently regulate the transcription of genes critical for vascular development, but their coordinated impact on vessels in late-stage embryos has not been explored. METHODS: In this study, we genetically deleted endothelial Brg1 and Chd4 in mixed background mice (Brg1fl/fl;Chd4fl/fl;VE-Cadherin-Cre), and littermates that were negative for Cre recombinase were used as controls. Tissues were analyzed by immunostaining, immunoblot, and flow cytometry. Quantitative reverse transcription polymerase chain reaction was used to determine gene expression, and chromatin immunoprecipitation revealed gene targets of BRG1 and CHD4 in cultured endothelial cells. RESULTS: We found Brg1/Chd4 double mutants grew normally but died soon after birth with small and compact lungs. Despite having normal cellular composition, distal air sacs of the mutant lungs displayed diminished ECM (extracellular matrix) components and TGFß (transforming growth factor-ß) signaling, which typically promotes ECM synthesis. Transcripts for collagen- and elastin-related genes and the TGFß ligand Tgfb1 were decreased in mutant lung endothelial cells, but genetic deletion of endothelial Tgfb1 failed to recapitulate the small lungs and ECM defects seen in Brg1/Chd4 mutants. We instead found several ECM genes to be direct targets of BRG1 and CHD4 in cultured endothelial cells. CONCLUSIONS: Collectively, our data highlight essential roles for endothelial chromatin-remodeling enzymes in promoting ECM deposition in the distal lung tissue during the saccular stage of embryonic lung development.
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Montagem e Desmontagem da Cromatina , DNA Helicases , Células Endoteliais , Regulação da Expressão Gênica no Desenvolvimento , Pulmão , Proteínas Nucleares , Fatores de Transcrição , Animais , DNA Helicases/metabolismo , DNA Helicases/genética , DNA Helicases/deficiência , Pulmão/embriologia , Pulmão/metabolismo , Pulmão/enzimologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Células Endoteliais/metabolismo , Células Endoteliais/enzimologia , Camundongos Knockout , Transdução de Sinais , Matriz Extracelular/metabolismo , Camundongos , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Camundongos Endogâmicos C57BL , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Fenótipo , Humanos , OrganogêneseRESUMO
BACKGROUND: The chromatin-remodeling enzyme BRG1 (brahma-related gene 1) regulates gene expression in a variety of rapidly differentiating cells during embryonic development. However, the critical genes that BRG1 regulates during lymphatic vascular development are unknown. METHODS: We used genetic and imaging techniques to define the role of BRG1 in murine embryonic lymphatic development, although this approach inadvertently expanded our study to multiple interacting cell types. RESULTS: We found that omental macrophages fine-tune an unexpected developmental process by which erythrocytes escaping from naturally discontinuous omental blood vessels are collected by nearby lymphatic vessels. Our data indicate that circulating fibrin(ogen) leaking from gaps in omental blood vessels can trigger inflammasome-mediated IL-1ß (interleukin-1ß) production and secretion from nearby macrophages. IL-1ß destabilizes adherens junctions in omental blood and lymphatic vessels, contributing to both extravasation of erythrocytes and their uptake by lymphatics. BRG1 regulates IL-1ß production in omental macrophages by transcriptionally suppressing the inflammasome trigger RIPK3 (receptor interacting protein kinase 3). CONCLUSIONS: Genetic deletion of Brg1 in embryonic macrophages leads to excessive IL-1ß production, erythrocyte leakage from blood vessels, and blood-filled lymphatics in the developing omentum. Altogether, these results highlight a novel context for epigenetically regulated crosstalk between macrophages, blood vessels, and lymphatics.
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Vasos Sanguíneos/metabolismo , DNA Helicases/metabolismo , Interleucina-1beta/metabolismo , Vasos Linfáticos/metabolismo , Proteínas Nucleares/metabolismo , Omento/metabolismo , Fatores de Transcrição/metabolismo , Junções Aderentes/metabolismo , Animais , Vasos Sanguíneos/embriologia , DNA Helicases/genética , Eritrócitos/metabolismo , Inflamassomos/metabolismo , Vasos Linfáticos/embriologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Omento/irrigação sanguínea , Omento/embriologia , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: During infectious diseases, proinflammatory cytokines transiently destabilize interactions between adjacent vascular endothelial cells (ECs) to facilitate the passage of immune molecules and cells into tissues. However, in the lung, the resulting vascular hyperpermeability can lead to organ dysfunction. Previous work identified the transcription factor ERG (erythroblast transformation-specific-related gene) as a master regulator of endothelial homeostasis. Here we investigate whether the sensitivity of pulmonary blood vessels to cytokine-induced destabilization is due to organotypic mechanisms affecting the ability of endothelial ERG to protect lung ECs from inflammatory injury. METHODS: Cytokine-dependent ubiquitination and proteasomal degradation of ERG were analyzed in cultured HUVECs (human umbilical vein ECs). Systemic administration of TNFα (tumor necrosis factor alpha) or the bacterial cell wall component lipopolysaccharide was used to cause a widespread inflammatory challenge in mice; ERG protein levels were assessed by immunoprecipitation, immunoblot, and immunofluorescence. Murine Erg deletion was genetically induced in ECs (Ergfl/fl;Cdh5[PAC]-CreERT2), and multiple organs were analyzed by histology, immunostaining, and electron microscopy. RESULTS: In vitro, TNFα promoted the ubiquitination and degradation of ERG in HUVECs, which was blocked by the proteasomal inhibitor MG132. In vivo, systemic administration of TNFα or lipopolysaccharide resulted in a rapid and substantial degradation of ERG within lung ECs but not ECs of the retina, heart, liver, or kidney. Pulmonary ERG was also downregulated in a murine model of influenza infection. Ergfl/fl;Cdh5(PAC)-CreERT2 mice spontaneously recapitulated aspects of inflammatory challenges, including lung-predominant vascular hyperpermeability, immune cell recruitment, and fibrosis. These phenotypes were associated with a lung-specific decrease in the expression of Tek-a gene target of ERG previously implicated in maintaining pulmonary vascular stability during inflammation. CONCLUSIONS: Collectively, our data highlight a unique role for ERG in pulmonary vascular function. We propose that cytokine-induced ERG degradation and subsequent transcriptional changes in lung ECs play critical roles in the destabilization of pulmonary blood vessels during infectious diseases.
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Doenças Transmissíveis , Fatores de Transcrição , Humanos , Camundongos , Animais , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Lipopolissacarídeos/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Citocinas/metabolismo , Doenças Transmissíveis/metabolismo , Células Cultivadas , Regulador Transcricional ERG/genética , Regulador Transcricional ERG/metabolismoRESUMO
Brown root rot disease (BRRD) is a highly destructive tree disease. Early diagnosis of BRRD has been challenging because the first symptoms and signs are often observed after extensive tissue colonization. Existing molecular detection methods, all based on the internal transcribed spacer (ITS) region, were developed without testing against global Phellinus noxius isolates, other wood-decay fungi, or host plant tissues. This study aimed to develop SYBR Green real-time quantitative PCR (qPCR) assays for P. noxius. The primer pair Pn_ITS_F/Pn_ITS_R targets the ITS, and the primer pair Pn_NLR_F/Pn_NLR_R targets a P. noxius-unique group of homologous genes identified through a comparative genomics analysis. The homologous genes belong to the nucleotide-binding-oligomerization-domain-like receptor (NLR) superfamily. The new primer pairs and a previous primer pair G1F/G1R were optimized for qPCR conditions and tested for specificity using 61 global P. noxius isolates, 5 other Phellinus species, and 22 non-Phellinus wood-decay fungal species. Although all three primer pairs could detect as little as 100 fg (approximately 2.99 copies) of P. noxius genomic DNA, G1F/G1R had the highest specificity and Pn_NLR_F/Pn_NLR_R had the highest efficiency. To avoid false positives, the cutoff quantification cycle values were determined as 34 for G1F/G1R, 29 for Pn_ITS_F/Pn_ITS_R, and 32 for Pn_NLR_F/Pn_NLR_R. We further validated these qPCR assays using Ficus benjamina seedlings artificially inoculated with P. noxius, six tree species naturally infected by P. noxius, rhizosphere soil, and bulk soil. The newly developed qPCR assays provide sensitive detection and quantification of P. noxius, which is useful for long-term monitoring of BRRD status.
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In response to injury, vascular smooth muscle cells (VSMCs) of the arterial wall dedifferentiate into a proliferative and migratory phenotype, leading to intimal hyperplasia. The ERK1/2 pathway participates in cellular proliferation and migration, while dual-specificity phosphatase 6 (DUSP6, also named MKP3) can dephosphorylate activated ERK1/2. We showed that DUSP6 was expressed in low baseline levels in normal arteries; however, arterial injury significantly increased DUSP6 levels in the vessel wall. Compared with wild-type mice, Dusp6-deficient mice had smaller neointima. In vitro, IL-1ß induced DUSP6 expression and increased VSMC proliferation and migration. Lack of DUSP6 reduced IL-1ß-induced VSMC proliferation and migration. DUSP6 deficiency did not affect IL-1ß-stimulated ERK1/2 activation. Instead, ERK1/2 inhibitor U0126 prevented DUSP6 induction by IL-1ß, indicating that ERK1/2 functions upstream of DUSP6 to regulate DUSP6 expression in VSMCs rather than downstream as a DUSP6 substrate. IL-1ß decreased the levels of cell cycle inhibitor p27 and cell-cell adhesion molecule N-cadherin in VSMCs, whereas lack of DUSP6 maintained their high levels, revealing novel functions of DUSP6 in regulating these two molecules. Taken together, our results indicate that lack of DUSP6 attenuated neointima formation following arterial injury by reducing VSMC proliferation and migration, which were likely mediated via maintaining p27 and N-cadherin levels.
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Fosfatases de Especificidade Dupla , Neointima , Lesões do Sistema Vascular , Animais , Camundongos , Caderinas , Movimento Celular , Proliferação de Células , Células Cultivadas , Fosfatases de Especificidade Dupla/genética , Hiperplasia , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso , Neointima/genética , Neointima/prevenção & controle , Lesões do Sistema Vascular/genéticaRESUMO
This study aims to investigate the mechanism of Linderae Radix water extract(LRWE) in the prevention and treatment of diarrhea-predominant irritable bowel syndrome(IBS-D) based on serum metabolomics. Eighteen 2-week-old male SD rats were randomized into control, IBS-D model, and LRWE groups. The rats in other groups except the control group received gavage of senna concentrate combined with restraint stress for the modeling of IBS-D. The rats in the LRWE group were administrated with LRWE(5.4 g·kg~(-1)) by gavage, and those in the control and IBS-D model groups with an equal volume of distilled water for a total of 14 days. The visceral sensitivity was evaluated by the abdominal withdrawal reflex(AWR) score, and the degree of diarrhea was assessed by the fecal water content(FWC). The morphological changes of the colon and the morphology and number of goblet cells were observed by hematoxylin-eosin(HE) and periodic acid-schiff(PAS) staining, respectively. Ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) was used for the screening of the potential biomarkers in the rat serum and their related metabolic pathways. The results showed that LRWE reduced the AWR score, decreased FWC, and alleviated visceral sensitivity and diarrhea symptoms in IBS-D rats. HE and PAS staining showed that LRWE mitigated low-grade intestinal inflammation and increased the number of mature secretory goblet cells in the colonic epithelium of IBS-D rats. A total of 25 potential biomarkers of LRWE in treating IBS-D were screened out in this study, which were mainly involved in riboflavin, tryptophan, glycine, serine and threonine metabolism, glyoxylate and dicarboxylate metabolism, and cysteine and methionine metabolism. The regulatory effects were the most significant on the riboflavin and tryptophan metabolism pathways. LRWE may alleviate the visceral hypersensitivity by promoting energy metabolism and amino acid metabolism, enhancing intestinal barrier function, and improving intestinal immune function in IBS-D rats.
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Síndrome do Intestino Irritável , Ratos , Masculino , Animais , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , Água , Cromatografia Líquida , Triptofano , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Diarreia/tratamento farmacológico , Biomarcadores , RiboflavinaRESUMO
Based on the DFT-level-calculated molecular volume (Vmol ) of pyrrole and its liquid density, pyrrole manifests the highest liquid density coefficient LDc (defined as [Vmol ×density ×0.6023]/FW) value of 0.7. Normal liquids have LDc <0.63. This very high LDc is due to the strong N-Hâ â â π interactions in solution, and hence pyrrole can be considered to be a pseudo-crystalline liquid. When trapped inside the confined space of a crystalline sponge, a reorientation of the N-Hâ â â π interaction is observed leading to specific cyclic N-Hâ â â π tetramers and N-Hâ â â π dimers, as verified by single-crystal X-ray crystallographic and computational methods. These tetramers are of the same size as four pyrrole molecules in the solid-state of pyrrole, yet the cyclic N-Hâ â â π intermolecular interactions are circularly oriented instead of being in the linear zigzag structure found in the X-ray structure of a solid pyrrole. The confinement thus acts as an external driving force for tetramer formation.
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Pirróis , Cristalografia por Raios X , Modelos MolecularesRESUMO
Zinc oxide nanoparticles (ZnONPs) are frequently encountered nanomaterials in our daily lives. Despite the benefits of ZnONPs in a variety of applications, many studies have shown potential health hazards of exposure to ZnONPs. We have shown that oropharyngeal aspiration of ZnONPs in mice increases lung inflammation. However, the detailed mechanisms underlying pulmonary inflammatory cell infiltration remain to be elucidated. Endothelium functions as a barrier between the blood stream and the blood vessel wall. Endothelial barrier dysfunction may increase infiltration of immune cells into the vessel wall and underlying tissues. This current study examined the effects of ZnONPs exposure on endothelial barriers. ZnONPs exposure increased leukocyte infiltration in the mouse lungs. In endothelial cells, ZnONPs reduced the continuity of tight junction proteins claudin-5 and zonula occludens-1 (ZO-1) at the cell junctions. ZnONPs induced adherens junction protein VE-cadherin internalization from membrane to cytosol and dissociation with ß-catenin, leading to reduced and diffused staining of VE-cadherin and ß-catenin at cell junctions. Our results demonstrated that ZnONPs disrupted both tight and adherens junctions, compromising the integrity and stability of the junction network, leading to inflammatory cell infiltration. Thus, ZnONPs exposure in many different settings should be carefully evaluated for vascular effects and subsequent health impacts.
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Claudina-5/genética , Endotélio/efeitos dos fármacos , Pneumonia/genética , Óxido de Zinco/efeitos adversos , Proteína da Zônula de Oclusão-1/genética , Junções Aderentes/efeitos dos fármacos , Junções Aderentes/genética , Animais , Vasos Sanguíneos/efeitos dos fármacos , Humanos , Leucócitos/efeitos dos fármacos , Camundongos , Nanopartículas/efeitos adversos , Orofaringe/efeitos dos fármacos , Pneumonia/induzido quimicamente , Pneumonia/patologiaRESUMO
Nodal is a member of transforming growth factor beta (TGF-ß) superfamily. Nodal promotes the self-renewal of human cancer stem cells (CSCs) and triggers carcinogenesis of human cancers via an autocrine manner through Smad2/3 pathway. In our study, generation of Nodal-overexpressed cancer cells was constructed, and the effect of Nodal on the stem cell marker Oct-4 was evaluated by overexpression or blocked Nodal/ALKs signaling pathway in non-small cell lung cancer cells A549 and prostate cancer cells PC3. Functionally, Nodal also increased the proliferation via the ß-catenin nuclear translocation. This increase was attributed to GSK-3ß dephosphorylating, and activin receptor-like kinase 4/7 (ALK4/7) played a major role in human cancer cells. Our study provides a positive understanding of Nodal function in cancer cells and suggests a potential novel target for clinical therapeutic research.
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Transporte Ativo do Núcleo Celular , Regulação Neoplásica da Expressão Gênica , Proteína Nodal/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Neoplasias da Próstata/metabolismo , beta Catenina/metabolismo , Células A549 , Receptores de Ativinas Tipo I/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Citoplasma/metabolismo , Humanos , Masculino , Transdução de Sinais , TransfecçãoRESUMO
BACKGROUND: Citrus exocortis viroid (CEVd) and Hop stunt viroid (HSVd) are commonly found simultaneously infecting different citrus cultivars in Taiwan. A crucial question to be addressed is how accumulations of these two viroids affect each other in an infected plant. In this study, we investigated the relationship between the two viroids at macroscopic and microscopic levels. METHODS: CEVd and HSVd titers were examined by real-time RT-PCR in 17 plants of two citrus cultivars (blood orange and Murcott mandarin) every 3 months (spring, summer, fall and winter) from 2011 to 2013. Three nonparametric tests (Spearman's rank correlation coefficient, Kendall's tau rank correlation coefficient and Hoeffding's inequality) were performed to test the correlation between CEVd and HSVd. Cellular and subcellular localizations of the two viroids were detected by digoxigenin- and colloidal gold-labeled in situ hybridization using light and transmission electron microscopy. RESULTS: The two viroids were unevenly distributed in four different types of citrus tissues (rootstock bark, roots, twig bark and leaves). Compared with blood orange, Murcott mandarin was generally more susceptible to CEVd and HSVd infection. Both viroids replicated and preferentially accumulated in the underground tissues of the two citrus cultivars. Except for blood orange at high temperatures, significant positive correlations were observed between the two viroids in specific tissues of both cultivars. Relative to concentrations under single-infection conditions, the CEVd population significantly increased under double infection during half of the 12 monitored seasons; in contrast, the population of HSVd significantly increased under double infection during only one season. At cellular/subcellular levels, the two viroids showed similar localization patterns in four tissues and the cells of these tissues in the two citrus cultivars. CONCLUSIONS: Our findings of titer enhancement, localization similarity, and lack of symptom aggravation under CEVd and HSVd double infection suggest that the two viroids have a positive relationship in citrus. The combination of molecular and cellular techniques used in this study provided evidence of titer correlation and localization of co-infecting viroids in the host. These methods may thus be useful tools for exploring viroid-viroid and viroid-host interactions.
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Citrus/virologia , Viroides/genética , Replicação Viral , Coinfecção/virologia , Doenças das Plantas/virologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taiwan , Carga ViralRESUMO
BACKGROUND: Two citrus viroids, Citrus exocortis viroid (CEVd) and Hop stunt viroid (HSVd), have been reported and become potential threats to the citrus industry in Taiwan. The distributions and infection rates of two viroids have not been investigated since the two diseases were presented decades ago. The genetic diversities and evolutionary relationships of two viroids also remain unclear in the mix citrus planted region. METHODS: Multiplex RT-PCR was used to detect the two viroids for the first time in seven main cultivars of citrus. Multiplex real-time RT-PCR quantified the distributions of two viroids in four citrus tissues. Sequence alignment and phylogenetic analysis were performed using the ClustalW and MEGA6 (neighbor-joining with p-distance model), respectively. RESULTS: HSVd was found more prevalent than CEVd (32.2% vs. 30.4%). Both CEVd and HSVd were commonly found simultaneously in the different citrus cultivars (up to 55%). Results of the multiplex quantitative analysis suggested that uneven distributions of both viroids with twig bark as the most appropriate material for studies involving viroid sampling such as quarantine inspection. Sequence alignment against Taiwanese isolates, along with analysis of secondary structure, revealed the existence of 10 and 5 major mutation sites in CEVd and HSVd, respectively. The mutation sites in CEVd were located at both ends of terminal and variability domains, whereas those in HSVd were situated in left terminal and pathogenicity domains. A phylogenetic analysis incorporating worldwide viroid isolates indicated three and two clusters for the Taiwanese isolates of CEVd and HSVd, respectively. CONCLUSIONS: Moderately high infection and co-infection rates of two viroids in certain citrus cultivars suggest that different citrus cultivars may play important roles in viroid infection and evolution. These data also demonstrate that two multiplex molecular detection methods developed in the present study provide powerful tools to understand the genetic diversities among viroid isolates and quantify viroids in citrus host. Our field survey can help clarify citrus-viroid relationships as well as develop proper prevention strategies.
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Citrus/virologia , Variação Genética , Doenças das Plantas/virologia , Viroides/classificação , Viroides/isolamento & purificação , Genótipo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Multiplex , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Taiwan , Viroides/genéticaRESUMO
BACKGROUND: Vascular smooth muscle cells (VSMCs) of the arterial wall play a critical role in the development of occlusive vascular diseases. Cysteine-rich protein 2 (CRP2) is a VSMC-expressed LIM-only protein, which functionally limits VSMC migration and protects against pathological vascular remodeling. The multifunctional cytokine TGFß has been implicated to play a role in the pathogenesis of atherosclerosis through numerous downstream signaling pathways. We showed previously that TGFß upregulates CRP2 expression; however, the detailed signaling mechanisms remain unclear. RESULTS: TGFß treatment of VSMCs activated both Smad2/3 and ATF2 phosphorylation. Individually knocking down Smad2/3 or ATF2 pathways with siRNA impaired the TGFß induction of CRP2, indicating that both contribute to CRP2 expression. Inhibiting TßRI kinase activity by SB431542 or TßRI knockdown abolished Smad2/3 phosphorylation but did not alter ATF2 phosphorylation, indicating while Smad2/3 phosphorylation was TßRI-dependent ATF2 phosphorylation was independent of TßRI. Inhibiting Src kinase activity by SU6656 suppressed TGFß-induced RhoA and ATF2 activation but not Smad2 phosphorylation. Blocking ROCK activity, the major downstream target of RhoA, abolished ATF2 phosphorylation and CRP2 induction but not Smad2 phosphorylation. Furthermore, JNK inhibition with SP600125 reduced TGFß-induced ATF2 (but not Smad2) phosphorylation and CRP2 protein expression while ROCK inhibition blocked JNK activation. These results indicate that downstream of TßRII, Src family kinase-RhoA-ROCK-JNK signaling pathway mediates TßRI-independent ATF2 activation. Promoter analysis revealed that the TGFß induction of CRP2 was mediated through the CRE and SBE promoter elements that were located in close proximity. CONCLUSIONS: Our results demonstrate that two signaling pathways downstream of TGFß converge on the CRE and SBE sites of the Csrp2 promoter to cooperatively control CRP2 induction in VSMCs, which represents a previously unrecognized mechanism of VSMC gene induction by TGFß.
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Proteínas de Transporte/metabolismo , Proteínas com Domínio LIM/metabolismo , Músculo Liso Vascular/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/farmacologia , Fator 2 Ativador da Transcrição/genética , Fator 2 Ativador da Transcrição/metabolismo , Animais , Proteínas de Transporte/genética , Células Cultivadas , Proteínas com Domínio LIM/genética , Camundongos , Músculo Liso Vascular/efeitos dos fármacos , Regiões Promotoras Genéticas , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismoRESUMO
Vascular smooth muscle cells (VSMCs) of the arterial wall normally display a differentiated and contractile phenotype. In response to arterial injury, VSMCs switch to a synthetic phenotype, contributing to vascular remodeling. Cysteine-rich protein 2 (CRP2) is a cytoskeletal protein expressed in VSMCs and blunts VSMC migration in part by sequestering the scaffolding protein p130Cas at focal adhesions. CRP2 deficiency in mice increases neointima formation following arterial injury. The goal of this study was to use Csrp2 promoter-lacZ transgenic mice to analyze CRP2 expression during VSMC phenotypic modulation. In a neointima formation model after carotid artery cessation of blood flow, lacZ reporter activity and smooth muscle (SM) α-actin expression in the media were rapidly downregulated 4 days after carotid ligation. Fourteen days after ligation, there was a high level expression of both Csrp2 promoter activity and SM α-actin protein expression in neointimal cells. In atherosclerosis prone mice fed an atherogenic diet, Csrp2 promoter activity was detected within complex atherosclerotic lesions. Interestingly, Csrp2 promoter activity was also present in the fibrous caps of complicated atherosclerotic lesions, indicating that CRP2 might contribute to plaque stability. These findings support the concept that CRP2 contributes to the phenotypic modulation of VSMCs during vascular disease. Modulating transcription to increase CRP2 expression during vascular injury might attenuate vascular remodeling. In addition, increased CRP2 expression at the fibrous caps of advanced lesions might also serve to protect atherosclerotic plaques from rupture.
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Aterosclerose/metabolismo , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica/fisiologia , Proteínas com Domínio LIM/metabolismo , Músculo Liso Vascular/metabolismo , Lesões do Sistema Vascular/metabolismo , Actinas/metabolismo , Animais , Artérias Carótidas/cirurgia , Proteínas de Transporte/genética , Movimento Celular/fisiologia , Primers do DNA/genética , Galactosídeos , Regulação da Expressão Gênica/genética , Genótipo , Técnicas Histológicas , Imuno-Histoquímica , Indóis , Proteínas com Domínio LIM/genética , Ligadura , Masculino , Camundongos , Camundongos Transgênicos , Neointima/fisiopatologia , Reação em Cadeia da PolimeraseRESUMO
Objective: Health self-monitoring technologies are gaining popularity worldwide, but they face low adoption rates in emerging countries. There is a deficiency in studies that have applied the value-belief-norm (VBN) model to understand the adoption of IoT-enabled wearable healthcare devices (WHDs). This study investigates the adoption of IoT-enabled WHDs among older adults in China, using the VBN model as a theoretical framework. Methods: Using a convenience sampling method and a web-based cross-sectional survey method, we collected data from 476 respondents, which we analyzed using partial least squares structural equation modeling using Smart PLS version 3.3.5. Results: The findings highlight the significance of health values and motivation in shaping personal health beliefs, which, in turn, influence personal norms and awareness of consequences. Particularly, awareness of consequences and attributions of responsibility significantly impact personal norms. Personal and social norms, in turn, strongly affect the intention to adopt IoT-enabled WHDs, ultimately driving their actual adoption. Conclusion: This research contributes novel insights into the behavioral dynamics surrounding the adoption of IoT-enabled WHDs, providing valuable guidance for marketers and policymakers. Marketers can leverage these insights to develop tailored marketing strategies within the IoT-enabled WHD industry. Additionally, policymakers are urged to prioritize campaigns aimed at enhancing awareness and understanding of self-healthcare monitoring, with a focus on promoting the unique health benefits of IoT-enabled WHDs.
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There are several modifiable factors that can be targeted to prevent and manage the occurrence and progression of cancer, and maintaining adequate exercise is a crucial one. Regular physical exercise has been shown to be a beneficial strategy in preventing cancer, potentially amplifying the effectiveness of established cancer therapies, alleviating certain cancer-related symptoms, and possibly mitigating side effects resulting from treatment. Nevertheless, the exact mechanisms by which exercise affects tumors, especially its impact on the tumor microenvironment (TME), remain uncertain. This review aims to present an overview of the beneficial effects of exercise in the context of cancer management, followed by a summary of the exercise parameters, especially exercise intensity, that need to be considered when prescribing exercise for cancer patients. Finally, we discuss the influence of exercise on the TME, including its effects on crucial immune cells (e.g., T cells, macrophages, neutrophils, natural killer cells, myeloid-derived suppressor cells, B cells), intratumor angiogenesis, and cancer metabolism. This comprehensive review provides up-to-date scientific evidence on the effects of exercise training on cancer and offers guidance to clinicians for the development of safe and feasible exercise training programs for cancer patients in clinical practice.
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Exercício Físico , Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/terapia , Terapia por Exercício , Neovascularização PatológicaRESUMO
This research aimed to identify the factors that influence impulse buying behavior during livestreaming and advance the existing literature based on a proposed conceptual framework grounded in the stimulus-organism-response (S-O-R) model. We also tested the moderating effects of price perception and scarcity persuasion. An online self-administered questionnaire was used to collect data from 837 Chinese participants aged over 18 years. The data were analyzed using partial least squares structural equation modeling using Smart-PLS version 4.0. The findings showed that susceptibility to social influence, impulse buying tendency, cognitive reactions, affective reactions, and the urge to buy impulsively are statistically significant predictors of impulse buying during livestreaming, with price perception and scarcity persuasion as moderators. The study expands the S-O-R model for livestreaming impulse buying in e-commerce context, highlighting its multifaceted nature and revealing the mediating role of Urge to Buy Impulsively in translating cognitive and emotional factors into impulse buying behavior. These insights offer practical guidance for marketers to design tailored strategies that leverage psychological triggers and external cues to enhance consumer engagement and encourage desired behaviors, ultimately leading to more effective marketing campaigns and improved consumer experiences.
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Brain metastases and lung metastases are major causes of treatment failure and related mortality in melanoma. Fluoxetine hydrochloride (FXT), a widely-used antidepressant, has emerged as a potential anticancer agent in preclinical studies. Previous research has shown its potential to inhibit melanoma. However, its efficacy and the underlying mechanisms in melanoma metastasis, especially concerning brain metastases and lung metastases, remain underexplored. This study investigates FXT's inhibitory effects on melanoma growth and metastasis to the lung and brain. Employing a combination of in vitro assays, we demonstrate FXT's potent suppression of melanoma growth through induction of intrinsic apoptosis, disruption of autophagic flux, and cell cycle arrest at the G0/G1 phase. In in vivo mouse models, we found that FXT exhibits strong inhibitory activity against melanoma brain metastases and lung metastases. Our findings provide a foundation for future clinical exploration of FXT as a novel treatment strategy for melanoma, underscoring its ability to target both primary and metastatic lesions.
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In line with the United Nation's sustainable development goals (SDGs), the unsustainable use of scarce natural resources and worldwide environmental degradation call for the immediate implementation of green behaviors across all organizations. As environmental issues originate from human activities, they necessitate the realization and execution of employees' workplace pro-environmental behaviors (WPEB) and their stimulators. Drawing on social exchange and social identity theories, this study first investigates the mediating role of green organizational climate in the relationship between various forms of perceived corporate social responsibility (CSR) and employees' WPEB. It further examines the mediated moderation via green shared vision. An adapted survey questionnaire was distributed to senior-level and middle-level managers of large and medium-sized manufacturing firms in Pakistan, and 349 responses were gathered. The partial least-squares technique was used for data analysis. The findings indicate that all forms of perceived CSR positively correlate with a green organizational climate, which further significantly leads to employees' WPEB. The results also show that a strong shared green vision among employees can improve the relationship between the green organizational climate and employees' WPEB and vice versa. Moreover, multi-group analysis shows that the relationship between customer-centric perceived CSR and green organizational climate was stronger for medium-sized firms than large ones. Thus, to ensure the implementation of SDGs such as decent work and climate action, firms' top management must recognize the importance of investing in both internal and external CSR initiatives to foster a green organizational climate leading to employees' WPEB. Companies should communicate their participation in CSR activities to all stakeholders through public platforms to increase inspiration. Policymakers should further introduce CSR excellence awards and non-compliance penalties to encourage firms' extensive participation.
RESUMO
The millions-worth revenue derived from large-scale food delivery characterises the service as a relatively established phenomenon with potential growth. The current cross-sectional research examined online food delivery service quality on consumer satisfaction and reuse intention. Service quality was divided into seven categories (i.e., reliability, assurance, security, maintaining food quality, system operation, traceability, and perceived service value). Perceived service value offer the unique understanding of the online food delivery consumer satisfaction. Empirical data were elicited from 1352 valid respondents and subsequently assessed through the partial least square structural equation modelling. Findings revealed that reliability, assurance, maintaining food quality, system operation, traceability, and perceived service value could elevate customer satisfaction and optimize the intention to reuse food delivery services. Specific measures to improve service quality, including staff training, improved after-sales service, and system optimisation, were proposed to increase users' satisfaction and intention to reuse optimally.
Assuntos
Comportamento do Consumidor , Intenção , Humanos , Reprodutibilidade dos Testes , Estudos Transversais , Qualidade dos Alimentos , Satisfação PessoalRESUMO
A series of two-dimensional (2D) spin-crossover coordination polymers (SCO-CPs) [FeII(TPE)(NCX)2]·solv (1: X = BH3, solv = H2O·2CH3OH·DMF; 2: X = Se, solv = H2O·2CH3OH·0.5DMF; 3: X = S, solv = H2O·2CH3OH·0.5DMF) were synthesized by employing 1,1,2,2-tetra(pyridin-4-yl)ethene (TPE) and pseudohalide (NCX-) coligands. Magnetic measurements indicated that complexes 1-3 exhibited SCO behaviors with diminishing thermal hysteresis (7/4/0 K) upon decreasing the ligand-field strength. The critical temperatures (Tc) during spin transition were found to be inversely proportional to the coordination ability parameters (a™) with a linear correlation. The guest effect was also investigated in the solvent-exchanged phases 1-SE/2-SE/3-SE wherein the DMF molecules were replaced by methanol molecules. Compared with 1-3, 1-SE/2-SE/3-SE displayed more abrupt and complete single-step SCO behaviors but narrower thermal hysteretic loops. The results reported here demonstrate that the Tc values of these two families were dominated by the ligand-field strength of the NCX- anions (NCBH3 > NCSe > NCS), whereas the guest effect only modulated the kinetic factor of the SCO nature in this system.