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1.
Gastroenterology ; 157(4): 1093-1108.e11, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31325428

RESUMO

BACKGROUND & AIMS: Inflammation, injury, and infection up-regulate expression of the tryptophan metabolizing enzyme indoleamine 2,3-dioxygenase 1 (IDO1) in the intestinal epithelium. We studied the effects of cell-specific IDO1 expression in the epithelium at baseline and during intestinal inflammation in mice. METHODS: We generated transgenic mice that overexpress fluorescence-tagged IDO1 in the intestinal epithelium under control of the villin promoter (IDO1-TG). We generated intestinal epithelial spheroids from mice with full-length Ido1 (controls), disruption of Ido1 (knockout mice), and IDO1-TG and analyzed them for stem cell and differentiation markers by real-time polymerase chain reaction, immunoblotting, and immunofluorescence. Some mice were gavaged with enteropathogenic Escherichia coli (E2348/69) to induce infectious ileitis, and ileum contents were quantified by polymerase chain reaction. Separate sets of mice were given dextran sodium sulfate or 2,4,6-trinitrobenzenesulfonic acid to induce colitis; intestinal tissues were analyzed by histology. We utilized published data sets GSE75214 and GDS2642 of RNA expression data from ilea of healthy individuals undergoing screening colonoscopies (controls) and patients with Crohn's disease. RESULTS: Histologic analysis of small intestine tissues from IDO1-TG mice revealed increases in secretory cells. Enteroids derived from IDO1-TG intestine had increased markers of stem, goblet, Paneth, enteroendocrine, and tuft cells, compared with control enteroids, with a concomitant decrease in markers of absorptive cells. IDO1 interacted non-enzymatically with the aryl hydrocarbon receptor to inhibit activation of NOTCH1. Intestinal mucus layers from IDO1-TG mice were 2-fold thicker than mucus layers from control mice, with increased proportions of Akkermansia muciniphila and Mucispirillum schaedleri. Compared to controls, IDO1-TG mice demonstrated an 85% reduction in ileal bacteria (P = .03) when challenged with enteropathogenic E coli, and were protected from immune infiltration, crypt dropout, and ulcers following administration of dextran sodium sulfate or 2,4,6-trinitrobenzenesulfonic acid. In ilea of Crohn's disease patients, increased expression of IDO1 correlated with increased levels of MUC2, LYZ1, and aryl hydrocarbon receptor, but reduced levels of SLC2A5. CONCLUSIONS: In mice, expression of IDO1 in the intestinal epithelial promotes secretory cell differentiation and mucus production; levels of IDO1 are positively correlated with secretory cell markers in ilea of healthy individuals and Crohn's disease patients. We propose that IDO1 contributes to intestinal homeostasis.


Assuntos
Bactérias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular , Microbioma Gastrointestinal , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Doenças Inflamatórias Intestinais/enzimologia , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/enzimologia , Mucosa Intestinal/microbiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores Notch/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Estudos de Casos e Controles , Linhagem Celular , Linhagem da Célula , Modelos Animais de Doenças , Células Epiteliais/enzimologia , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Genótipo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/deficiência , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Camundongos Knockout , Fenótipo , Receptores de Hidrocarboneto Arílico/genética , Receptores Notch/genética , Via Secretória , Transdução de Sinais , Células-Tronco/enzimologia , Células-Tronco/microbiologia , Células-Tronco/patologia
2.
Life Sci ; 232: 116630, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279783

RESUMO

AIMS: Lung adenocarcinoma consists of multiple therapeutic targets, however, patients will inevitably progress to later stage diagnosis with Tyrosine Kinase Inhibitor treatment resistance. We aim to investigate the roles of non-coding TUSC7 in ordering the cell division tendency, helping to sensitize the resistance in a miRNA incorporating way. MATERIALS AND METHODS: Online study of bioinformatics analysis, molecular experiments of luciferase test, immunofluorescence staining and qRT-PCR were applied to dig out the mechanistic regulations. KEY FINDINGS: TUSC-7 inhibited the renewal ability of adenocarcinoma stem cells, yielding to asymmetric cell splitting. Informatics analysis and the luciferase testing confirmed the 3'UTR binding site, and revealed the post-transcriptional regulation of NUMB referring to miR-146. TUSC-7 sponged miR-146 and abolished its degradation toward to NUMB, and this integrated cascade made several genes become tangled to full functionality. SIGNIFICANCE: TUSC-7 was proved to be one strong suppressive lnc-RNA in lung adenocarcinoma stem cells, functioning through inactivating NOTCH signaling, and the turbulence on division modes precisely pointed to the key mechanisms of stem cells' renewal. The decreasing of tumor suppressive miR-146 was necessary in TUSC-7 conducted renewal repression, despite it alone could also reduce the renewal efficiency, indicating that more complicated non-coding genes may be involved in its regulation.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/metabolismo , RNA Longo não Codificante/fisiologia , Regiões 3' não Traduzidas , Adenocarcinoma de Pulmão/genética , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Humanos , Neoplasias Pulmonares/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo
3.
PLoS Genet ; 15(4): e1008058, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30933982

RESUMO

In the skin and gill epidermis of fish, ionocytes develop alongside keratinocytes and maintain body fluid ionic homeostasis that is essential for adaptation to environmental fluctuations. It is known that ionocyte progenitors in zebrafish embryos are specified from p63+ epidermal stem cells through a patterning process involving DeltaC (Dlc)-Notch-mediated lateral inhibition, which selects scattered dlc+ cells into the ionocyte progenitor fate. However, mechanisms by which the ionocyte progenitor population is modulated remain unclear. Krüppel-like factor 4 (Klf4) transcription factor was previously implicated in the terminal differentiation of mammalian skin epidermis and is known for its bifunctional regulation of cell proliferation in a tissue context-dependent manner. Here, we report novel roles for zebrafish Klf4 in the ventral ectoderm during embryonic skin development. We found that Klf4 was expressed in p63+ epidermal stem cells of the ventral ectoderm from 90% epiboly onward. Knockdown or knockout of klf4 expression reduced the proliferation rate of p63+ stem cells, resulting in decreased numbers of p63+ stem cells, dlc-p63+ keratinocyte progenitors and dlc+ p63+ ionocyte progenitor cells. These reductions subsequently led to diminished keratinocyte and ionocyte densities and resulted from upregulation of the well-known cell cycle regulators, p53 and cdkn1a/p21. Moreover, mutation analyses of the KLF motif in the dlc promoter, combined with VP16-klf4 or engrailed-klf4 mRNA overexpression analyses, showed that Klf4 can bind the dlc promoter and modulate lateral inhibition by directly repressing dlc expression. This idea was further supported by observing the lateral inhibition outcomes in klf4-overexpressing or knockdown embryos. Overall, our experiments delineate novel roles for zebrafish Klf4 in regulating the ionocyte progenitor population throughout early stem cell stage to initiation of terminal differentiation, which is dependent on Dlc-Notch-mediated lateral inhibition.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Padronização Corporal , Diferenciação Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ectoderma/citologia , Ectoderma/embriologia , Ectoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Brânquias/citologia , Brânquias/embriologia , Brânquias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transporte de Íons , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Receptores Notch/genética , Receptores Notch/metabolismo , Transativadores/genética , Transativadores/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
4.
Genes Dev ; 33(9-10): 498-510, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30842215

RESUMO

Developmental signal transduction pathways act diversely, with context-dependent roles across systems and disease types. Glioblastomas (GBMs), which are the poorest prognosis primary brain cancers, strongly resemble developmental systems, but these growth processes have not been exploited therapeutically, likely in part due to the extreme cellular and genetic heterogeneity observed in these tumors. The role of Wnt/ßcatenin signaling in GBM stem cell (GSC) renewal and fate decisions remains controversial. Here, we report context-specific actions of Wnt/ßcatenin signaling in directing cellular fate specification and renewal. A subset of primary GBM-derived stem cells requires Wnt proteins for self-renewal, and this subset specifically relies on Wnt/ßcatenin signaling for enhanced tumor burden in xenograft models. In an orthotopic Wnt reporter model, Wnthi GBM cells (which exhibit high levels of ßcatenin signaling) are a faster-cycling, highly self-renewing stem cell pool. In contrast, Wntlo cells (with low levels of signaling) are slower cycling and have decreased self-renewing potential. Dual inhibition of Wnt/ßcatenin and Notch signaling in GSCs that express high levels of the proneural transcription factor ASCL1 leads to robust neuronal differentiation and inhibits clonogenic potential. Our work identifies new contexts for Wnt modulation for targeting stem cell differentiation and self-renewal in GBM heterogeneity, which deserve further exploration therapeutically.


Assuntos
Diferenciação Celular/genética , Células-Tronco Neoplásicas/citologia , Transdução de Sinais , Linhagem Celular Tumoral , Autorrenovação Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/fisiopatologia , Humanos , Receptores Notch/genética , Receptores Notch/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
5.
J Biosci ; 44(1)2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30837354

RESUMO

To examine the protective effect of transplanting bone marrow mesenchymal stem cells (BMSCs) in treating lung injuryinduced by smoke exposure and to investigate the underlying mechanisms of this protection. SD rats were randomlydivided into four groups: normal group, normal +BMSCGFP group, smoke group, and smoke +BMSCGFP group. Todetect lung injury, we measured arterial blood gas, the wet-to-dry weight ratio, and levels of interleukin-1b, tumor necrosisfactor-a, interleukin-10, and interleukin-13 in bronchoalveolar lavage fluid and lung tissues. We also conductedhistopathology examinations. The protein markers of alveolar epithelial cells were measured to determine the BMSCdifferentiation. The protein levels of Notch1, Jagged-1, and Hes-1 also were detected. In the present study, BMSCtransplantation significantly decreased the wet-dry weight ratio of the lung, reduced the production of inflammatorymediators, and alleviated lung injury simply through differentiating into alveolar type II cells and alveolar type I cells. Western blot analysis confirmed that the protein expression of Notch-1, Jagged-1, and Hes-1 increased significantly aftersystemic BMSC transplantation. No significant difference was observed between the normal group and the nor-mal +BMSCGFP group. Our findings indicate that systemic transplantation of BMSCs alleviated lung injury induced bysmoke exposure, which may be associated with BMSCs' ability to differentiate into alveolar-type cells via the Notchsignaling pathway.


Assuntos
Proteína Jagged-1/genética , Transplante de Células-Tronco Mesenquimais , Receptor Notch1/genética , Lesão por Inalação de Fumaça/terapia , Fatores de Transcrição HES-1/genética , Células Epiteliais Alveolares/citologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Humanos , Interleucina-10/metabolismo , Interleucina-13/metabolismo , Interleucina-1beta/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Notch/genética , Transdução de Sinais/genética , Lesão por Inalação de Fumaça/genética , Lesão por Inalação de Fumaça/patologia
6.
Int J Mol Sci ; 20(6)2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917608

RESUMO

Head and neck squamous cell carcinoma (HNSCC) defines a group of solid tumors originating from the mucosa of the upper aerodigestive tract, pharynx, larynx, mouth, and nasal cavity. It has a metastatic evolution and poor prognosis and is the sixth most common cancer in the world, with 600,000 new cases reported every year. HNSCC heterogeneity and complexity is reflected in a multistep progression, involving crosstalk between several molecular pathways. The Notch pathway is associated with major events supporting cancerogenic evolution: cell proliferation, self-renewal, angiogenesis, and preservation of a pro-oncogenic microenvironment. Additionally, Notch is pivotal in tumor development and plays a dual role acting as both oncogene and tumor suppressor. In this review, we summarize the role of the Notch pathway in HNSCC, with a special focus on its compelling role in major events of tumor initiation and growth.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Receptores Notch/metabolismo , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Receptores Notch/genética , Transdução de Sinais
7.
Artif Cells Nanomed Biotechnol ; 47(1): 833-843, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30862190

RESUMO

We aimed to explore the mediating role of Notch signal in macrophage polarization. This signal was knocked out from macrophages of Lyz2 cre and RBP-J flox mice. Bone marrow-derived macrophages (BMDMs) were isolated and polarized. The expressions of polarization markers in BMDMs 24 h after transfection were detected by qPCR. After Notch knockout, the expressions of M1 markers decreased but those of M2 markers increased significantly. MiR-125a/miR-99b and Spaca6 were highly and lowly expressed upon M1 and M2 polarizations, respectively. The expressions of experimental group were significantly lower than those of control group. Overexpression of miR-125a significantly promoted the expressions of M1 markers, whereas inhibited those of M2 markers. NO release in the culture supernatant of miR-125a overexpression group significantly exceeded that of control group. Transfection with miR-125a inhibitor significantly down-regulated IL-12 expression but up-regulated MR expression in BMDMs. The supernatant secreted by M1 macrophages significantly facilitated BS524 cell apoptosis, which was enhanced after miR-125a overexpression. The TNF-α expression of miR-99b overexpression group increased whereas that of MR decreased significantly. The miR-125a/miR-99b cluster contained an RBP-J specific recognition site in the first intron of initial transcript. The Notch signalling pathway promoted macrophage polarization into M1 phenotype by up-regulating miR-125a/miR-99b expression.


Assuntos
Regulação da Expressão Gênica , Macrófagos/imunologia , MicroRNAs/genética , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Técnicas de Inativação de Genes , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Ativação de Macrófagos/genética , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , MicroRNAs/antagonistas & inibidores , Fenótipo , Receptores Notch/genética , Proteínas de Plasma Seminal/genética
8.
Development ; 146(3)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30709911

RESUMO

Most cells in our body communicate during development and throughout life via Notch receptors and their ligands. Notch receptors relay information from the cell surface to the genome via a very simple mechanism, yet Notch plays multiple roles in development and disease. Recent studies suggest that this versatility in Notch function may not necessarily arise from complex and context-dependent integration of Notch signaling with other developmental signals, but instead arises, in part, from signaling dynamics. Here, we review recent findings on the core Notch signaling mechanism and discuss how spatial-temporal dynamics contribute to Notch signaling output.


Assuntos
Receptores Notch/metabolismo , Transdução de Sinais , Animais , Humanos , Receptores Notch/genética
10.
J Mol Neurosci ; 67(4): 632-642, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30758748

RESUMO

Notch signalling pathway is involved in the proliferation of neural progenitor cells (NPCs), to inhibit neuronal cell commitment and to promote glial cell fate. Notch protein is cleaved by gamma-secretase, a multisubunit transmembrane protein complex that releases the Notch intracellular domain (NICD) and subsequently activates the downstream targets. Down syndrome (DS) individuals exhibit an increased number of glial cells (particularly astrocytes), and reduced number of neurons suggesting the involvement of Notch signalling pathway in the neurogenic-to-gliogenic shift in DS brain. Ts1Cje is a DS mouse model that exhibit similar neuropathology to human DS individuals. To date, the spatiotemporal gene expression of the Notch and gamma-secretase genes have not been characterised in Ts1Cje mouse brain. Understanding the expression pattern of Notch and gamma-secretase genes may provide a better understanding of the underlying mechanism that leads to the shift. Gene expression analysis using RT-qPCR was performed on early embryonic and postnatal development of DS brain. In the developing mouse brain, mRNA expression analysis showed that gamma-secretase members (Psen1, Pen-2, Aph-1b, and Ncstn) were not differentially expressed. Notch2 was found to be downregulated in the developing Ts1Cje brain samples. Postnatal gene expression study showed complex expression patterns and Notch1 and Notch2 genes were found to be significantly downregulated in the hippocampus at postnatal day 30. Results from RT-qPCR analysis from E15.5 neurosphere culture showed an increase of expression of Psen1, and Aph-1b but downregulation of Pen-2 and Ncstn genes. Gamma-secretase activity in Ts1Cje E15.5 neurospheres was significantly increased by fivefold. In summary, the association and the role of Notch and gamma-secretase gene expression throughout development with neurogenic-to-gliogenic shift in Ts1Cje remain undefined and warrant further validation.


Assuntos
Secretases da Proteína Precursora do Amiloide/genética , Síndrome de Down/metabolismo , Hipocampo/metabolismo , Receptores Notch/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Notch/metabolismo , Transdução de Sinais
11.
Proc Natl Acad Sci U S A ; 116(9): 3695-3702, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30755532

RESUMO

Scleroderma (SSc) is a complex disease that involves activation of the immune system, vascular complications, and tissue fibrosis. The histone methyltransferase enhancer of zeste homolog 2 (EZH2) mediates trimethylation of lysine 27 of histone 3 (H3K27me3), which acts as a repressive epigenetic mark. Both EZH2 and H3K27me3 were elevated in SSc dermal fibroblasts and endothelial cells compared with healthy controls. EZH2 inhibitor DZNep halted fibrosis both in vitro and in vivo. In SSc fibroblasts, DZNep dose-dependently reduced the expression of profibrotic genes and inhibited migratory activity of SSc fibroblasts. We show that epigenetic dysregulation and overexpression of LRRC16A explains EZH2-mediated fibroblast migration in SSc. In endothelial cells, inhibition of EZH2 restored normal angiogenesis in SSc via activating the Notch pathway, specifically by up-regulating the Notch ligand DLL4. Our results demonstrate that overexpression of EZH2 in SSc fibroblasts and endothelial cells is profibrotic and antiangiogenic. Targeting EZH2 or EZH2-regulated genes might be of therapeutic potential in SSc.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/genética , Fibrose/genética , Proteínas dos Microfilamentos/genética , Esclerodermia Difusa/genética , Animais , Bleomicina/toxicidade , Movimento Celular/genética , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Repressão Epigenética/genética , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose/induzido quimicamente , Fibrose/patologia , Regulação da Expressão Gênica/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/genética , Metilação , Camundongos , Neovascularização Fisiológica , Receptores Notch/genética , Transdução de Sinais
12.
Science ; 363(6431): 1085-1088, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30705153

RESUMO

Hypercholesterolemia, the driving force of atherosclerosis, accelerates the expansion and mobilization of hematopoietic stem and progenitor cells (HSPCs). The molecular determinants connecting hypercholesterolemia with hematopoiesis are unclear. Here, we report that a somite-derived prohematopoietic cue, AIBP, orchestrates HSPC emergence from the hemogenic endothelium, a type of specialized endothelium manifesting hematopoietic potential. Mechanistically, AIBP-mediated cholesterol efflux activates endothelial Srebp2, the master transcription factor for cholesterol biosynthesis, which in turn transactivates Notch and promotes HSPC emergence. Srebp2 inhibition impairs hypercholesterolemia-induced HSPC expansion. Srebp2 activation and Notch up-regulation are associated with HSPC expansion in hypercholesterolemic human subjects. Genome-wide chromatin immunoprecipitation followed by sequencing (ChIP-seq), RNA sequencing (RNA-seq), and assay for transposase-accessible chromatin using sequencing (ATAC-seq) indicate that Srebp2 transregulates Notch pathway genes required for hematopoiesis. Our studies outline an AIBP-regulated Srebp2-dependent paradigm for HSPC emergence in development and HPSC expansion in atherosclerotic cardiovascular disease.


Assuntos
Colesterol/biossíntese , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Hipercolesterolemia/metabolismo , Animais , Anticolesterolemiantes/farmacologia , Atorvastatina/farmacologia , Sequência de Bases , Imunoprecipitação da Cromatina , Doença da Artéria Coronariana/metabolismo , Regulação da Expressão Gênica , Hematopoese/genética , Receptores Notch/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Peixe-Zebra
13.
Hereditas ; 156: 5, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30679936

RESUMO

Background: The Notch signaling pathway governs the specification of different cell types in flies, nematodes and vertebrates alike. Principal components of the pathway that activate Notch target genes are highly conserved throughout the animal kingdom. Despite the impact on development and disease, repression mechanisms are less well studied. Repressors are known from arthropods and vertebrates that differ strikingly by mode of action: whereas Drosophila Hairless assembles repressor complexes with CSL transcription factors, competition between activator and repressors occurs in vertebrates (for example SHARP/MINT and KyoT2). This divergence raises questions on the evolution: Are there common ancestors throughout the animal kingdom? Results: Available genome databases representing all animal clades were searched for homologues of Hairless, SHARP and KyoT2. The most distant species with convincing Hairless orthologs belong to Myriapoda, indicating its emergence after the Mandibulata-Chelicarata radiation about 500 million years ago. SHARP shares motifs with SPEN and SPENITO proteins, present throughout the animal kingdom. The CSL interacting domain of SHARP, however, is specific to vertebrates separated by roughly 600 million years of evolution. KyoT2 bears a C-terminal CSL interaction domain (CID), present only in placental mammals but highly diverged already in marsupials, suggesting introduction roughly 100 million years ago. Based on the LIM-domains that characterize KyoT2, homologues can be found in Drosophila melanogaster (Limpet) and Hydra vulgaris (Prickle 3 like). These lack the CID of KyoT2, however, contain a PET and additional LIM domains. Conservation of intron/exon boundaries underscores the phylogenetic relationship between KyoT2, Limpet and Prickle. Most strikingly, Limpet and Prickle proteins carry a tetra-peptide motif resembling that of several CSL interactors. Overall, KyoT2 may have evolved from prickle and Limpet to a Notch repressor in mammals. Conclusions: Notch repressors appear to be specific to either chordates or arthropods. Orthologues of experimentally validated repressors were not found outside the phylogenetic group they have been originally identified. However, the data provide a hypothesis on the evolution of mammalian KyoT2 from Prickle like ancestors. The finding of a potential CSL interacting domain in Prickle homologues points to a novel, very ancestral CSL interactor present in the entire animal kingdom.


Assuntos
Evolução Molecular , Receptores Notch/genética , Transdução de Sinais , Sequência de Aminoácidos , Animais , Drosophila melanogaster , Invertebrados , Ligação Proteica , Estrutura Terciária de Proteína , Vertebrados
14.
Mater Sci Eng C Mater Biol Appl ; 97: 593-601, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678946

RESUMO

Diabetes mellitus is an epidemic worldwide. Pancreatic stem cells can be induced to differentiate into insulin-secreting cells, this method is an effective way to solve the shortage of islet donor. Poly (lactic acid-co-glycolic acid (PLGA) copolymer is an excellent scaffold for tissue engineering as it presents good biocompatibility and film forming properties. In this study, we adopted biological methods, using fibroblast-coated PLGA diaphragm to form a biological membrane, and then pancreatic stem cells were cultured on the fibroblast-modified PLGA membrane and the two-step induction method was utilized to induce the differentiation of pancreatic stem cells into insulin-secreting cells. The proliferation and differentiation of pancreatic stem cells on the fibroblast-modified PLGA membrane as well as the expression of genes related to the differentiation of pancreatic stem cells were examined in both normal and induced cultures to explore the potential of fibroblast-modified PLGA membrane for the transplantation to treat diabetes mellitus. The results indicated that fibroblasts can effectively improve the cell compatibility and histocompatibility of the PLGA membrane and promote the proliferation and differentiation of pancreatic stem cells. After induction, real-time fluorescence quantitative PCR (FQRT-PCR) results showed there were more Notch receptors and its ligands expressed in the membranes of pancreatic stem cells than non-induced pancreatic stem cells or fibroblast. Semiconductor quantum dot coupled-anti-complex probe experiments revealed that induced pancreatic stem cells had higher expression levels of Notch 2 and Delta-like 1 than non-induced ones, which may regulate the expression of Neurogenin-3 (Ngn3) and Hairy/Enhancer of split-1 gene (Hes1) through Notch signaling interaction between fibroblasts and pancreatic stem cells as well as enhance the proliferation of pancreatic stem cells and their differentiation into insulin-secreting cells. Further, our study suggests that the fibroblast-modified PLGA membrane can be used as matrix material composed of pancreatic stem cells or other stem cells to construct artificial islet tissue for the treatment of diabetes mellitus.


Assuntos
Diferenciação Celular , Células Secretoras de Insulina/metabolismo , Pâncreas/citologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Células-Tronco/citologia , Animais , Técnicas de Cultura de Células/métodos , Células Cultivadas , Colágeno Tipo IV/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Glucose/farmacologia , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteoglicanas/metabolismo , Ratos Wistar , Receptores Notch/genética , Receptores Notch/metabolismo , Células-Tronco/metabolismo , Tecidos Suporte/química
15.
Oncogene ; 38(17): 3201-3215, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30626939

RESUMO

Ovarian carcinoma is the most lethal type of gynecologic malignancies. Alterations of Notch pathway are prevalent in ovarian carcinogenesis. This study investigated the expression profile and function of delta-like 1 homolog (DLK1), a non-canonical Notch ligand, during ovarian carcinogenesis. Tissue microarray (TMA) consisting of surgically resected samples from 221 patients with ovarian carcinoma was constructed for DLK1 expression. DLK1 overexpression or knockdown was achieved by adenovirus gene delivery to evaluate the effect of DLK1 on the oncogenic behaviors in ovarian cancer cells and in xenografted tumors. TMA analysis revealed that elevated DLK1 expression was correlated with stages, lymph node metastasis and E-cadherin downregulation. Despite no influence on survival among ovarian carcinoma patients, DLK1 overexpression was specially associated with overall survival and progression free survival in high-grade serous carcinoma (HGSC) patients, constituting an independent prognostic factor for these patients. By adenovirus gene delivery, it was found modulation of cellular DLK1 level regulated the tumorigenic behaviors and epithelial-mesenchymal transition (EMT) in vitro and in vivo. Immunohistochemical analysis further showed that DLK1 overexpression resulted in escalated proliferation, angiogenesis, EMT and Notch activities. Application of recombinant DLK1 extracellular domain (rDLK1-EC) recapitulated the tumorigenic behaviors of DLK1 in ovarian cancer cells. By using neutralizing antibody or pharmaceutical inhibitor, blockade of Notch signaling attenuated the tumorigenic behaviors evoked by DLK1 overexpression. The present study indicates that DLK1 overexpression participates in ovarian carcinogenesis through Notch activation and EMT induction. Moreover, DLK1 may constitute a novel diagnostic biomarker and therapeutic target for HGSC.


Assuntos
Carcinogênese/genética , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patologia , Transição Epitelial-Mesenquimal/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Receptores Notch/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Feminino , Humanos , Transdução de Sinais/genética
16.
Arch Oral Biol ; 99: 134-140, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30682716

RESUMO

OBJECTIVES: The present study aimed to investigate the expression of Notch signaling components during osteogenic differentiation in vitro and bone healing in vivo. In addition, the influence of Notch signaling on osteogenic differentiation of human bone-derived cells was examined. METHODS: Gene expression profiling of osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells in vitro (GSE80614) and bone healing period of murine tibial fracture in vivo (GSE99388) was downloaded from Gene Expression Omnibus database. The expression of Notch signaling components was obtained from bioinformatic tools. Human bone-derived cells were isolated from alveolar and iliac bone. Cells were seeded on Jagged1 immobilized surface. Osteogenic marker gene expression and mineralization were examined using real-time polymerase chain reaction and alizarin red s staining, respectively. RESULTS: From bioinformatic analysis of gene expression profiling, various Notch signaling components were differentially expressed during osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells in vitro and bone healing period of murine tibial fracture in vivo. The common genes differentially regulated of these two datasets were Hes1, Aph1a, Nsctn, Furin, Adam17, Hey1, Pcsk5, Nedd4, Jag1, Heyl, Notch3, Dlk1, and Hey2. For an in vitro analysis, the mineral deposition markedly increased after seeding human bone-derived cells on Jagged1 immobilized surface, correspondingly with the increase of ALP mRNA expression. Jagged1 treatment downregulated TWIST2 mRNA expression in both human alveolar and iliac bone-derived cells. CONCLUSION: Notch signaling is regulated during osteogenic differentiation and bone healing. In addition, the activation of Notch signaling promotes osteogenic differentiation in human alveolar and iliac bone-derived cells. Therefore, Notch signaling manipulation could be a useful approach for enhancing bone regeneration.


Assuntos
Calcificação Fisiológica/fisiologia , Proteína Jagged-1/metabolismo , Osteócitos/metabolismo , Osteogênese/fisiologia , Receptores Notch/metabolismo , Transdução de Sinais , Proteína ADAM17/genética , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Endopeptidases/genética , Furina/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Ílio/efeitos dos fármacos , Ílio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteína Jagged-1/genética , Proteína Jagged-1/farmacologia , Células-Tronco Mesenquimais , Camundongos , Ubiquitina-Proteína Ligases Nedd4/genética , Osteócitos/efeitos dos fármacos , Osteogênese/genética , Pró-Proteína Convertase 5 , RNA Mensageiro , Receptor Notch3/genética , Receptores Notch/genética , Proteínas Repressoras/genética , Fraturas da Tíbia/genética , Fraturas da Tíbia/metabolismo , Fatores de Transcrição HES-1/genética
17.
Circulation ; 139(1): 78-96, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30586693

RESUMO

BACKGROUND: Chronic kidney disease (CKD) increases cardiovascular risk. Underlying mechanisms, however, remain obscure. The uremic toxin indoxyl sulfate is an independent cardiovascular risk factor in CKD. We explored the potential impact of indoxyl sulfate on proinflammatory activation of macrophages and its underlying mechanisms. METHODS: We examined in vitro the effects of clinically relevant concentrations of indoxyl sulfate on proinflammatory responses of macrophages and the roles of organic anion transporters and organic anion transporting polypeptides (OATPs). A systems approach, involving unbiased global proteomics, bioinformatics, and network analysis, then explored potential key pathways. To address the role of Delta-like 4 (Dll4) in indoxyl sulfate-induced macrophage activation and atherogenesis in CKD in vivo, we used 5/6 nephrectomy and Dll4 antibody in low-density lipoprotein receptor-deficient (Ldlr-/-) mice. To further determine the relative contribution of OATP2B1 or Dll4 to proinflammatory activation of macrophages and atherogenesis in vivo, we used siRNA delivered by macrophage-targeted lipid nanoparticles in mice. RESULTS: We found that indoxyl sulfate-induced proinflammatory macrophage activation is mediated by its uptake through transporters, including OATP2B1, encoded by the SLCO2B1 gene. The global proteomics identified potential mechanisms, including Notch signaling and the ubiquitin-proteasome pathway, that mediate indoxyl sulfate-triggered proinflammatory macrophage activation. We chose the Notch pathway as an example of key candidates for validation of our target discovery platform and for further mechanistic studies. As predicted computationally, indoxyl sulfate triggered Notch signaling, which was preceded by the rapid induction of Dll4 protein. Dll4 induction may result from inhibition of the ubiquitin-proteasome pathway, via the deubiquitinating enzyme USP5. In mice, macrophage-targeted OATP2B1/Slco2b1 silencing and Dll4 antibody inhibited proinflammatory activation of peritoneal macrophages induced by indoxyl sulfate. In low-density lipoprotein receptor-deficient mice, Dll4 antibody abolished atherosclerotic lesion development accelerated in Ldlr-/- mice. Moreover, coadministration of indoxyl sulfate and OATP2B1/Slco2b1 or Dll4 siRNA encapsulated in macrophage-targeted lipid nanoparticles in Ldlr-/- mice suppressed lesion development. CONCLUSIONS: These results suggest that novel crosstalk between OATP2B1 and Dll4-Notch signaling in macrophages mediates indoxyl sulfate-induced vascular inflammation in CKD.


Assuntos
Aterosclerose/metabolismo , Indicã/toxicidade , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Receptores Notch/metabolismo , Insuficiência Renal Crônica/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Transportadores de Ânions Orgânicos/genética , Fenótipo , Placa Aterosclerótica , Células RAW 264.7 , Receptores de LDL/deficiência , Receptores de LDL/genética , Receptores Notch/genética , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Transdução de Sinais/efeitos dos fármacos , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia
18.
Neoplasia ; 21(1): 93-105, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30529074

RESUMO

Interactions of multiple myeloma (MM) cells with endothelial cells (ECs) enhance angiogenesis and MM progression. Here, we investigated the role of Notch signaling in the cross talk between ECs and MM cells enabling angiogenesis. MMECs showed higher expression of Jagged1/2 ligands, of activated Notch1/2 receptors, and of Hes1/Hey1 Notch target genes than ECs from monoclonal gammopathy of undetermined significance patients, suggesting that homotypic activation of Notch pathway occurs in MM. MM cells co-cultured with MMECs triggered Notch activation in these cells through a cell-to-cell contact-dependent way via Jagged1/2, resulting in Hes1/Hey1 overexpression. The angiogenic effect of Notch pathway was analyzed through Notch1/2·siRNAs and the γ-secretase inhibitor MK-0752 by in vitro (adhesion, migration, chemotaxis, angiogenesis) and in vivo (Vk12598/C57B/6 J mouse model) studies. Activated Notch1/2 pathway was associated with the overangiogenic MMEC phenotype: Notch1/2 knockdown or MK-0752 treatment reduced Hes1/Hey1 expression, impairing in vitro angiogenesis of both MMECs alone and co-cultured with MM cells. MM cells were unable to restore angiogenic abilities of treated MMECs, proving that MMEC angiogenic activities closely rely on Notch pathway. Furthermore, Notch1/2 knockdown affected VEGF/VEGFR2 axis, indicating that the Notch pathway interferes with VEGF-mediated control on angiogenesis. MK-0752 reduced secretion of proangiogenic/proinflammatory cytokines in conditioned media, thus inhibiting blood vessel formation in the CAM assay. In the Vk12598/C57B/6 J mouse, MK-0752 treatment restrained angiogenesis by reducing microvessel density. Overall, homotypic and heterotypic Jagged1/2-mediated Notch activation enhances MMECs angiogenesis. Notch axis inhibition blocked angiogenesis in vitro and in vivo, suggesting that the Notch pathway may represent a novel therapeutic target in MM.


Assuntos
Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Neovascularização Patológica/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Derivados de Benzeno/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Camundongos , Gamopatia Monoclonal de Significância Indeterminada/tratamento farmacológico , Gamopatia Monoclonal de Significância Indeterminada/metabolismo , Gamopatia Monoclonal de Significância Indeterminada/patologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Neovascularização Patológica/genética , Propionatos/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Receptores Notch/genética , Transdução de Sinais/efeitos dos fármacos , Sulfonas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Development ; 146(1)2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30559277

RESUMO

The elongating mouse anteroposterior axis is supplied by progenitors with distinct tissue fates. It is not known whether these progenitors confer anteroposterior pattern to the embryo. We have analysed the progenitor population transcriptomes in the mouse primitive streak and tail bud throughout axial elongation. Transcriptomic signatures distinguish three known progenitor types (neuromesodermal, lateral/paraxial mesoderm and notochord progenitors; NMPs, LPMPs and NotoPs). Both NMP and LPMP transcriptomes change extensively over time. In particular, NMPs upregulate Wnt, Fgf and Notch signalling components, and many Hox genes as progenitors transit from production of the trunk to the tail and expand in number. In contrast, the transcriptome of NotoPs is stable throughout axial elongation and they are required for normal axis elongation. These results suggest that NotoPs act as a progenitor niche whereas anteroposterior patterning originates within NMPs and LPMPs.


Assuntos
Padronização Corporal/fisiologia , Embrião de Mamíferos/embriologia , Mesoderma/embriologia , Notocorda/embriologia , Transdução de Sinais/fisiologia , Animais , Embrião de Mamíferos/citologia , Mesoderma/citologia , Camundongos , Camundongos Transgênicos , Notocorda/citologia , Linha Primitiva/citologia , Linha Primitiva/embriologia , Receptores Notch/genética , Receptores Notch/metabolismo
20.
PLoS One ; 13(12): e0207140, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30540745

RESUMO

Atonal homolog 1 (Atoh1) is a basic helix-loop-helix 9 (bHLH) transcription factor acting downstream of Notch and is required for the differentiation of sensory hair cells in the inner ear and the specification of secretory cells during the intestinal crypt cell regeneration. Motivated by the observations that the upregulation of Atoh1 gene expression, through genetic manipulation or pharmacological inhibition of Notch signaling (e.g. γ-secretase inhibitors, GSIs), induces ectopic hair cell growth in the cochlea of the inner ear and partially restores hearing after injuries in experimental models, we decided to identify small molecule modulators of the Notch-Atoh1 pathway, which could potentially regenerate hair cells. However, the lack of cellular models of the inner ear has precluded the screening and characterization of such modulators. Here we report using a colon cancer cell line LS-174T, which displays Notch inhibition-dependent Atoh1 expression as a surrogate cellular model to screen for inducers of Atoh1 expression. We designed an Atoh1 promoter-driven luciferase assay to screen a target-annotated library of ~6000 compounds. We further developed a medium throughput, real-time quantitative RT-PCR assay measuring the endogenous Atoh1 gene expression to confirm the hits and eliminate false positives from the reporter-based screen. This strategy allowed us to successfully recover GSIs of known chemotypes. This LS-174T cell-based assay directly measures Atoh1 gene expression induced through Notch-Hes1 inhibition, and therefore offers an opportunity to identify novel cellular modulators along the Notch-Atoh1 pathway.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Receptores Notch/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Benzodiazepinas/farmacologia , Linhagem Celular Tumoral , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Microscopia de Fluorescência , Regiões Promotoras Genéticas , Receptores Notch/antagonistas & inibidores , Transdução de Sinais , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo
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