Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Mol Biol Cell ; 35(1): br3, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37903230

RESUMO

Apical extrusion is a tissue-intrinsic process that allows epithelia to eliminate unfit or surplus cells. This is exemplified by the early extrusion of apoptotic cells, which is critical to maintain the epithelial barrier and prevent inflammation. Apoptotic extrusion is an active mechanical process, which involves mechanotransduction between apoptotic cells and their neighbors, as well as local changes in tissue mechanics. Here we report that the preexisting mechanical tension at adherens junctions (AJs) conditions the efficacy of apoptotic extrusion. Specifically, increasing baseline mechanical tension by overexpression of a phosphomimetic Myosin II regulatory light chain (MRLC) compromises apoptotic extrusion. This occurs when tension is increased in either the apoptotic cell or its surrounding epithelium. Further, we find that the proinflammatory cytokine, TNFα, stimulates Myosin II and increases baseline AJ tension to disrupt apical extrusion, causing apoptotic cells to be retained in monolayers. Importantly, reversal of mechanical tension with an inhibitory MRLC mutant or tropomyosin inhibitors is sufficient to restore apoptotic extrusion in TNFα-treated monolayers. Together, these findings demonstrate that baseline levels of tissue tension are important determinants of apoptotic extrusion, which can potentially be coopted by pathogenetic factors to disrupt the homeostatic response of epithelia to apoptosis.


Assuntos
Junções Aderentes , Células Epiteliais , Junções Aderentes/metabolismo , Células Epiteliais/metabolismo , Mecanotransdução Celular , Fator de Necrose Tumoral alfa , Epitélio/metabolismo , Miosina Tipo II/metabolismo
2.
J Plast Reconstr Aesthet Surg ; 86: 150-154, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37717299

RESUMO

INTRODUCTION: The United Kingdom (UK) injectables market has been growing rapidly with a lack of robust regulation and to date, no information regarding the profile of practitioners has been published. AIM: We aim to provide a descriptive and qualitative analysis of the advertised practitioners in the United Kingdom. METHODS: We performed a systematic search using the internet search engine Google to perform a qualitative descriptive analysis of aesthetic practitioners in the UK. For each contiguous country in the UK: England, Scotland, and Wales, five searches were performed. The list of practitioners was then cross-referenced with professional regulatory bodies, with extraction of registration number, date of registration and presence or absence from the Specialist Register or General Practitioner Register. RESULTS: 3000 websites were visited and evaluated. 1224 independent clinics with 4405 practitioners were identified. 738 were identified as those in business support functions and the remaining 3667 practitioners were undertaking injectable practice. The profile of professions were doctors 32%, nurses 13%, dentists 24% and dental nurses 8%. Of the 1163 doctors identified 481 were on the specialist register (41%) and 219 were on the GP register (19%). 27 specialties were represented in this cohort analysis. Plastic Surgery formed the majority of those who were on the specialist register at 37%, followed by Dermatology at 18%. CONCLUSION: This paper is the first to describe the range of practitioners, their professional backgrounds and experience who perform non-surgical aesthetic interventions. The range of backgrounds may have an impact on the potential risks to patients and will be an important consideration in proposed legislation to introduce licensing to the industry.


Assuntos
Médicos , Procedimentos de Cirurgia Plástica , Humanos , Reino Unido , Inglaterra , Estudos de Coortes
3.
Cell Mol Gastroenterol Hepatol ; 16(6): 985-1009, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37660948

RESUMO

BACKGROUND & AIMS: MUC13 cell surface mucin is highly expressed on the mucosal surface throughout the intestine, yet its role against bacterial infection is unknown. We investigated how MUC13 impacts Salmonella typhimurium (S Tm) infection and elucidated its mechanisms of action. METHODS: Muc13-/- and wild-type littermate mice were gavaged with 2 isogenic strains of S Tm after pre-conditioning with streptomycin. We assessed clinical parameters, cecal histology, local and systemic bacterial load, and proinflammatory cytokines after infection. Cecal enteroids and epithelial cell lines were used to evaluate the mechanism of MUC13 activity after infection. The interaction between bacterial SiiE and MUC13 was assessed by using siiE-deficient Salmonella. RESULTS: S Tm-infected Muc13-/- mice had increased disease activity, histologic damage, and higher local and systemic bacterial loads. Mechanistically, we found that S Tm binds to MUC13 through its giant SiiE adhesin and that MUC13 acts as a pathogen-binding decoy shed from the epithelial cell surface after pathogen engagement, limiting bacterial invasion. In addition, MUC13 reduces epithelial cell death and intestinal barrier breakdown by enhancing nuclear factor kappa B signaling during infection, independent of its decoy function. CONCLUSIONS: We show for the first time that MUC13 plays a critical role in antimicrobial defense against pathogenic S Tm at the intestinal mucosal surface by both acting as a releasable decoy limiting bacterial invasion and reducing pathogen-induced cell death. This further implicates the cell surface mucin family in mucosal defense from bacterial infection.


Assuntos
Infecções Bacterianas , Mucinas , Animais , Camundongos , Infecções Bacterianas/genética , Infecções Bacterianas/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/patologia , Mucinas/metabolismo , Salmonella typhimurium/metabolismo
4.
Amyloid ; 30(2): 169-187, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36411500

RESUMO

BACKGROUND: [18F]flutemetamol is a PET radioligand used to image brain amyloid, but its detection of myocardial amyloid is not well-characterized. This histological study characterized binding of fluorescently labeled flutemetamol (cyano-flutemetamol) to amyloid deposits in myocardium. METHODS: Myocardial tissue was obtained post-mortem from 29 subjects with cardiac amyloidosis including transthyretin wild-type (ATTRwt), hereditary/variant transthyretin (ATTRv) and immunoglobulin light-chain (AL) types, and from 10 cardiac amyloid-free controls. Most subjects had antemortem electrocardiography, echocardiography, SPECT and cardiac MRI. Cyano-flutemetamol labeling patterns and integrated density values were evaluated relative to fluorescent derivatives of Congo red (X-34) and Pittsburgh compound-B (cyano-PiB). RESULTS: Cyano-flutemetamol labeling was not detectable in control subjects. In subjects with cardiac amyloidosis, cyano-flutemetamol labeling matched X-34- and cyano-PiB-labeled, and transthyretin- or lambda light chain-immunoreactive, amyloid deposits and was prevented by formic acid pre-treatment of myocardial sections. Cyano-flutemetamol mean fluorescence intensity, when adjusted for X-34 signal, was higher in the ATTRwt than the AL group. Cyano-flutemetamol integrated density correlated strongly with echocardiography measures of ventricular septal thickness and posterior wall thickness, and with heart mass. CONCLUSION: The high selectivity of cyano-flutemetamol binding to myocardial amyloid supports the diagnostic utility of [18F]flutemetamol PET imaging in patients with ATTR and AL types of cardiac amyloidosis.


Assuntos
Amiloidose , Placa Amiloide , Humanos , Placa Amiloide/patologia , Pré-Albumina/genética , Pré-Albumina/metabolismo , Miocárdio/patologia , Benzotiazóis/metabolismo , Amiloidose/metabolismo , Amiloide/metabolismo , Proteínas Amiloidogênicas/metabolismo
5.
Inflamm Bowel Dis ; 28(12): 1800-1812, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35993552

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) involves chronic T cell-mediated inflammatory responses. Vedolizumab (VDZ), a monoclonal antibody against α4ß7 integrin, inhibits lymphocyte extravasation into intestinal mucosae and is effective in ulcerative colitis (UC) and Crohn's disease (CD). AIM: We sought to identify immune cell phenotypic and gene expression signatures that related to response to VDZ. METHODS: Peripheral blood (PBMC) and lamina propria mononuclear cells (LPMCs) were analyzed by flow cytometry and Cytofkit. Sorted CD4 + memory (Tmem) or regulatory T (Treg) cells from PBMC and LPMC were analyzed by RNA sequencing (RNA-seq). Clinical response (≥2-point drop in partial Mayo scores [UC] or Harvey-Bradshaw index [CD]) was assessed 14 to 22 weeks after VDZ initiation. Machine-learning models were used to infer combinatorial traits that predicted response to VDZ. RESULTS: Seventy-one patients were enrolled: 37 received VDZ and 21 patients remained on VDZ >2 years. Fourteen of 37 patients (38%; 8 UC, 6 CD) responded to VDZ. Immune cell phenotypes and CD4 + Tmem and Treg transcriptional behaviors were most divergent between the ileum and colon, irrespective of IBD subtype or inflammation status. Vedolizumab treatment had the greatest impact on Treg metabolic pathways, and response was associated with increased expression of genes involved in oxidative phosphorylation. The strongest clinical predictor of VDZ efficacy was concurrent use of thiopurines. Mucosal tissues offered the greatest number of response-predictive biomarkers, whereas PBMC Treg-expressed genes were the best predictors in combinatorial models of response. CONCLUSIONS: Mucosal and peripheral blood immune cell phenotypes and transcriptional profiles can inform VDZ efficacy and inform new opportunities for combination therapies.


Vedolizumab (VDZ) is effective in the treatment of IBD. Immunophenotyping and RNAseq of T cells were used to inform its mechanism of action. Changes in T regulatory cells in the periphery and mucosa have the greatest relationship to VDZ response.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Fármacos Gastrointestinais/uso terapêutico , Linfócitos T Reguladores/metabolismo , Leucócitos Mononucleares/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Resultado do Tratamento
6.
Cell Mol Gastroenterol Hepatol ; 14(4): 789-811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35809803

RESUMO

BACKGROUND & AIMS: MUC1 is abnormally expressed in colorectal cancer, including colitis-associated colorectal cancer (CAC), but its role in tumorigenesis is unclear. This study investigated MUC1's effects in murine models of colitis and CAC and elucidated mechanisms of action. METHODS: Colitis and CAC were induced in mice by exposure to dextran sodium sulfate or azoxymethane plus dextran sodium sulphate. Clinical parameters, immune cell infiltration, and tumor development were monitored throughout disease progression. Experiments in knockout mice and bone marrow chimeras were combined with an exploration of immune cell abundance and function. RESULTS: Deficiency of Muc1 suppressed inflammation, inhibited tumor progression, increased abundance of CD8+ T lymphocytes, and reduced abundance of macrophages in colon tumors. Bone marrow chimeras showed promotion of CAC was primarily mediated by Muc1-expressing hematopoietic cells, and that MUC1 promoted a pro-tumoral immunosuppressive macrophage phenotype within tumors. Mechanistic studies revealed that Muc1 deficiency remarkably reduced interleukin-6 levels in the colonic tissues and tumors that was mainly produced by infiltrating macrophages at day 21, 42, and 85. In bone marrow-derived macrophages, MUC1 promoted responsiveness to chemoattractant and promoted activation into a phenotype with high Il6 and Ido1 expression, secreting factors which inhibited CD8+ T cell proliferation. MUC1 potently drives macrophages to produce interleukin-6, which in turn drives a pro-tumorigenic activation of signal transducer and activator of transcription 3 in colon epithelial tumor and stromal cells, ultimately increasing the occurrence and development of CAC. CONCLUSIONS: Our findings provide cellular and molecular mechanisms for the pro-tumorigenic functions of MUC1 in the inflamed colon. Therapeutic strategies to inhibit MUC1 signal transduction warrant consideration for the prevention or therapy of CAC.


Assuntos
Neoplasias Associadas a Colite , Interleucina-6 , Ativação de Macrófagos , Mucina-1 , Fator de Transcrição STAT3 , Animais , Azoximetano/toxicidade , Carcinogênese , Fatores Quimiotáticos , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Neoplasias Associadas a Colite/genética , Neoplasias Associadas a Colite/imunologia , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Sulfato de Dextrana/toxicidade , Interleucina-6/genética , Interleucina-6/imunologia , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Camundongos , Camundongos Knockout , Mucina-1/genética , Mucina-1/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia
7.
Genes (Basel) ; 13(3)2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35327957

RESUMO

Breast tumour kinase (Brk/PTK6) is overexpressed in up to 86% of breast cancers and is associated with poorer patient outcomes. It is considered a potential therapeutic target in breast cancer, even though the full spectrum of its kinase activity is not known. This study investigated the role of the kinase domain in promoting tumour growth and its potential in sensitising triple negative breast cancer cells to standard of care chemotherapy. Triple negative human xenograft models revealed that both kinase-inactive and wild-type Brk promoted xenograft growth. Suppression of Brk activity in cells subsequently co-treated with the chemotherapy agents doxorubicin or paclitaxel resulted in an increased cell sensitivity to these agents. In triple negative breast cancer cell lines, the inhibition of Brk kinase activity augmented the effects of doxorubicin or paclitaxel. High expression of the alternatively spliced isoform, ALT-PTK6, resulted in improved patient outcomes. Our study is the first to show a role for kinase-inactive Brk in human breast tumour xenograft growth; therefore, it is unlikely that kinase inhibition of Brk, in isolation, would halt tumour growth in vivo. Breast cancer cell responses to chemotherapy in vitro were kinase-dependent, indicating that treatment with kinase inhibitors could be a fruitful avenue for combinatorial treatment. Of particular prognostic value is the ratio of ALT-PTK6:Brk expression in predicating patient outcomes.


Assuntos
Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Xenoenxertos , Humanos , Proteínas de Neoplasias , Paclitaxel/farmacologia , Proteínas Tirosina Quinases , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
8.
Int J Mol Med ; 47(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33649798

RESUMO

Severe acute respiratory syndrome (SARS) coronavirus­2 (SARS­CoV­2), the causative viral agent for the ongoing COVID­19 pandemic, enters its host cells primarily via the binding of the SARS­CoV­2 spike (S) proteins to the angiotensin­converting enzyme 2 (ACE2). A number of other cell entry mediators have also been identified, including neuropilin­1 (NRP1) and transmembrane protease serine 2 (TMPRSS2). More recently, it has been demonstrated that transmembrane protease serine 4 (TMPRSS4) along with TMPRSS2 activate the SARS­CoV­2 S proteins, and enhance the viral infection of human small intestinal enterocytes. To date, a systematic analysis of TMPRSS4 in health and disease is lacking. In the present study, using in silico tools, the gene expression and genetic alteration of TMPRSS4 were analysed across numerous tumours and compared to controls. The observations were also expanded to the level of the central nervous system (CNS). The findings revealed that TMPRSS4 was overexpressed in 11 types of cancer, including lung adenocarcinoma, lung squamous cell carcinoma, cervical squamous cell carcinoma, thyroid carcinoma, ovarian cancer, cancer of the rectum, pancreatic cancer, colon and stomach adenocarcinoma, uterine carcinosarcoma and uterine corpus endometrial carcinoma, whilst it was significantly downregulated in kidney carcinomas, acute myeloid leukaemia, skin cutaneous melanoma and testicular germ cell tumours. Finally, a high TMPRSS4 expression was documented in the olfactory tubercle, paraolfactory gyrus and frontal operculum, all brain regions which are associated with the sense of smell and taste. Collectively, these data suggest that TMPRSS4 may play a role in COVID­19 symptomatology as another SARS­CoV­2 host cell entry mediator responsible for the tropism of this coronavirus both in the periphery and the CNS.


Assuntos
COVID-19/enzimologia , COVID-19/genética , Proteínas de Membrana/genética , SARS-CoV-2/fisiologia , SARS-CoV-2/patogenicidade , Serina Endopeptidases/genética , Internalização do Vírus , Encéfalo/enzimologia , COVID-19/virologia , Sistema Nervoso Central/enzimologia , Simulação por Computador , Bases de Dados Genéticas , Feminino , Trato Gastrointestinal/enzimologia , Perfilação da Expressão Gênica , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Masculino , Proteínas de Membrana/fisiologia , Neoplasias/enzimologia , Neoplasias/genética , Pandemias , Serina Endopeptidases/fisiologia
9.
Immunol Cell Biol ; 99(6): 622-639, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33565143

RESUMO

The endothelial adhesion protein E-selectin/CD62E is not required for leukocyte homing, unlike closely related family member P-selectin/CD62P. As transmigration through the endothelium is one of the first steps in generating a local immune response, we hypothesized that E-selectin may play additional roles in the early stages of immune activation. We found contact with E-selectin, but not P-selectin or vascular cell adhesion molecule 1 (CD106), induced phosphorylation of protein kinase B (AKT) and nuclear factor-κB in mouse bone marrow-derived macrophages (BMDMs) in vitro. This occurred within 15 min of E-selectin contact and was dependent on phosphatidylinositol-3 kinase activity. Binding to E-selectin activated downstream proteins including mammalian target of rapamycin, p70 ribosomal protein S6 kinase and eukaryotic translation initiation factor 4E-binding protein 1. Functionally, adhesion to E-selectin induced upregulation of CD86 expression and CCL2 secretion. We next asked whether contact with E-selectin impacts further BMDM stimulation. We found enhanced secretion of both interleukin (IL)-10 and CCL2, but not tumor necrosis factor or IL-6 in response to lipopolysaccharide (LPS) stimulation after adhesion to E-selectin. Importantly, adhesion to E-selectin did not polarize BMDMs to one type of response but enhanced both arginase activity and nitric oxide production following IL-4 or LPS stimulation, respectively. In cultured human monocytes, adhesion to E-selectin similarly induced phosphorylation of AKT. Finally, when E-selectin was blocked in vivo in mice, thioglycollate-elicited macrophages showed reduced CD86 expression, validating our in vitro studies. Our results imply functions for E-selectin beyond homing and suggest that E-selectin plays an early role in priming and amplifying innate immune responses.


Assuntos
Selectina E , Proteínas Proto-Oncogênicas c-akt , Animais , Adesão Celular , Células Cultivadas , Endotélio Vascular , Macrófagos , Camundongos , Serina-Treonina Quinases TOR
10.
Cell Mol Gastroenterol Hepatol ; 11(1): 33-53, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32497793

RESUMO

BACKGROUND & AIMS: Chronic bowel inflammation increases the risk of colon cancer; colitis-associated cancer (CAC). Thiopurine treatments are associated with a reduction in dysplasia and CAC in inflammatory bowel disease (IBD). Abnormal Wnt/ß-catenin signalling is characteristic of >90% of colorectal cancers. Immunosuppression by thiopurines is via Rac1 GTPase, which also affects Wnt/ß-catenin signalling. Autophagy is implicated in colonic tumors, and topical delivery of the thiopurine thioguanine (TG) is known to alleviate colitis and augment autophagy. This study investigated the effects of TG in a murine model of CAC and potential mechanisms. METHODS: Colonic dysplasia was induced by exposure to azoxymethane (AOM) and dextran sodium sulfate (DSS) in wild-type (WT) mice and mice harboring intestinal epithelial cell-specific deletion of autophagy related 7 gene (Atg7ΔIEC). TG or vehicle was administered intrarectally, and the effect on tumor burden and ß-catenin activity was assessed. The mechanisms of action of TG were investigated in vitro and in vivo. RESULTS: TG ameliorated DSS colitis in wild-type but not Atg7ΔIEC mice, demonstrating that anti-inflammatory effects of locally delivered TG are autophagy-dependent. However, TG inhibited CAC in both wild-type and Atg7ΔIEC mice. This was associated with decreased ß-catenin activation/nuclear translocation demonstrating that TG's inhibition of tumorigenesis occurred independently of anti-inflammatory and pro-autophagic actions. These results were confirmed in cell lines, and the dependency on Rac1 GTPase was demonstrated by siRNA knockdown and overexpression of constitutively active Rac1. CONCLUSIONS: Our findings provide evidence for a new mechanism that could be exploited to improve CAC chemoprophylactic approaches.


Assuntos
Neoplasias Associadas a Colite/prevenção & controle , Colite/tratamento farmacológico , Tioguanina/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Administração Retal , Animais , Autofagia/efeitos dos fármacos , Autofagia/genética , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Azoximetano/administração & dosagem , Azoximetano/toxicidade , Células CACO-2 , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Neoplasias Associadas a Colite/imunologia , Neoplasias Associadas a Colite/patologia , Colo/efeitos dos fármacos , Colo/patologia , Sulfato de Dextrana/administração & dosagem , Sulfato de Dextrana/toxicidade , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mercaptopurina/farmacologia , Mercaptopurina/uso terapêutico , Camundongos , Camundongos Transgênicos , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Tioguanina/uso terapêutico , beta Catenina/análise , beta Catenina/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
11.
Gastroenterology ; 160(3): 797-808.e6, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33127391

RESUMO

BACKGROUND & AIMS: Chronic colonic inflammation leads to dysplasia and cancer in patients with inflammatory bowel disease. We have described the critical role of innate immune signaling via Toll-like receptor 4 (TLR4) in the pathogenesis of dysplasia and cancer. In the current study, we interrogate the intersection of TLR4 signaling, epithelial redox activity, and the microbiota in colitis-associated neoplasia. METHODS: Inflammatory bowel disease and colorectal cancer data sets were analyzed for expression of TLR4, dual oxidase 2 (DUOX2), and NADPH oxidase 1 (NOX1). Epithelial production of hydrogen peroxide (H2O2) was analyzed in murine colonic epithelial cells and colonoid cultures. Colorectal cancer models were carried out in villin-TLR4 mice, carrying a constitutively active form of TLR4, their littermates, and villin-TLR4 mice backcrossed to DUOXA-knockout mice. The role of the TLR4-shaped microbiota in tumor development was tested in wild-type germ-free mice. RESULTS: Activation of epithelial TLR4 was associated with up-regulation of DUOX2 and NOX1 in inflammatory bowel disease and colorectal cancer. DUOX2 was exquisitely dependent on TLR4 signaling and mediated the production of epithelial H2O2. Epithelial H2O2 was significantly increased in villin-TLR4 mice; TLR4-dependent tumorigenesis required the presence of DUOX2 and a microbiota. Mucosa-associated microbiota transferred from villin-TLR4 mice to wild-type germ-free mice caused increased H2O2 production and tumorigenesis. CONCLUSIONS: Increased TLR4 signaling in colitis drives expression of DUOX2 and epithelial production of H2O2. The local milieu imprints the mucosal microbiota and imbues it with pathogenic properties demonstrated by enhanced epithelial reactive oxygen species and increased development of colitis-associated tumors. The inter-relationship between epithelial reactive oxygen species and tumor-promoting microbiota requires a 2-pronged strategy to reduce the risk of dysplasia in colitis patients.


Assuntos
Colite Ulcerativa/complicações , Neoplasias Associadas a Colite/patologia , Oxidases Duais/metabolismo , Microbioma Gastrointestinal/imunologia , Receptor 4 Toll-Like/metabolismo , Animais , Azoximetano/administração & dosagem , Azoximetano/toxicidade , Carcinogênese/induzido quimicamente , Carcinogênese/imunologia , Carcinogênese/patologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/imunologia , Colite Ulcerativa/microbiologia , Neoplasias Associadas a Colite/imunologia , Neoplasias Associadas a Colite/microbiologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/microbiologia , Colo/patologia , Conjuntos de Dados como Assunto , Sulfato de Dextrana/administração & dosagem , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Vida Livre de Germes , Humanos , Peróxido de Hidrogênio/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , NADPH Oxidase 1/metabolismo , Receptor 4 Toll-Like/genética
12.
Nat Commun ; 11(1): 2042, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341362

RESUMO

The endothelial cell adhesion molecule E-selectin is a key component of the bone marrow hematopoietic stem cell (HSC) vascular niche regulating balance between HSC self-renewal and commitment. We now report in contrast, E-selectin directly triggers signaling pathways that promote malignant cell survival and regeneration. Using acute myeloid leukemia (AML) mouse models, we show AML blasts release inflammatory mediators that upregulate endothelial niche E-selectin expression. Alterations in cell-surface glycosylation associated with oncogenesis enhances AML blast binding to E-selectin and enable promotion of pro-survival signaling through AKT/NF-κB pathways. In vivo AML blasts with highest E-selectin binding potential are 12-fold more likely to survive chemotherapy and main contributors to disease relapse. Absence (in Sele-/- hosts) or therapeutic blockade of E-selectin using small molecule mimetic GMI-1271/Uproleselan effectively inhibits this niche-mediated pro-survival signaling, dampens AML blast regeneration, and strongly synergizes with chemotherapy, doubling the duration of mouse survival over chemotherapy alone, whilst protecting endogenous HSC.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Selectina E/antagonistas & inibidores , Selectina E/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Medula Óssea , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Glicolipídeos/uso terapêutico , Glicosilação , Células-Tronco Hematopoéticas/citologia , Humanos , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
13.
Front Cell Dev Biol ; 8: 600575, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33634096

RESUMO

Much attention has recently been focused on nutraceuticals, with minimal adverse effects, developed for preventing or treating neurological diseases such as Alzheimer's disease (AD). The present study was conducted to investigate the potential effect on neural development and function of the microalgae Aurantiochytrium sp. as a nutraceutical. To test neuroprotection by the ethanol extract of Aurantiochytrium (EEA) and a derivative, the n-Hexane layer of EEA (HEEA), amyloid-ß-stimulated SH-SY5Y cells, was used as an in vitro AD model. We then assessed the potential enhancement of neurogenesis by EEA and HEEA using murine ex vivo neurospheres. We also administered EEA or HEEA to senescence-accelerated mouse-prone 8 (SAMP8) mice, a non-transgenic strain with accelerated aging and AD-like memory loss for evaluation of spatial learning and memory using the Morris water maze test. Finally, we performed immunohistochemical analysis for assessment of neurogenesis in mice administered EEA. Pretreatment of SH-SY5Y cells with EEA or the squalene-rich fraction of EEA, HEEA, ameliorated amyloid-ß-induced cytotoxicity. Interestingly, only EEA-treated cells showed a significant increase in cell metabolism and intracellular adenosine triphosphate production. Moreover, EEA treatment significantly increased the number of neurospheres, whereas HEEA treatment significantly increased the number of ß-III-tubulin+ young neurons and GFAP+ astrocytes. SAMP8 mice were given 50 mg/kg EEA or HEEA orally for 30 days. EEA and HEEA decreased escape latency in the Morris water maze in SAMP8 mice, indicating improved memory. To detect stem cells and newborn neurons, we administered BrdU for 9 days and measured BrdU+ cells in the dentate gyrus, a neurogenic stem cell niche of the hippocampus. In SAMP8 mice, EEA rapidly and significantly increased the number of BrdU+GFAP+ stem cells and their progeny, BrdU+NeuN+ mature neurons. In conclusion, our data in aggregate indicate that EEA and its constituents could be developed into a nutraceutical for promoting brain health and function against several age-related diseases, particularly AD.

14.
Cell Mol Gastroenterol Hepatol ; 9(3): 387-402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31740421

RESUMO

BACKGROUND & AIMS: The interaction between intestinal microbiota and the immune system plays a vital role in inflammatory bowel disease (IBD). Although numerous deep-sequencing studies have suggested dysbiosis in IBD, identifying specific bacteria from the stool or mucosa that are responsible for disease susceptibility or severity has remained a challenge. Lamina propria phagocytes ideally are localized to interact with bacteria that are in close proximity to, or have invaded, the tissue. Thus, we examined the microbial populations associated with the lamina propria phagocytes in 20 Crohn's disease and 12 ulcerative colitis patients. Specifically, we aimed to address whether the phagocyte-associated microbiota differed from the mucosa-associated microbiota and whether this varied based on IBD type or the state of inflammation. METHODS: 16S ribosomal RNA gene sequencing and innate immune gene expression profiling was done on CD11b+ lamina propria phagocytes isolated from the biopsies obtained from IBD patients. RESULTS: Phagocyte-associated microbiota was enriched in bacterial species belonging to phylum Proteobacteria, whereas species belonging to phylum Bacteroidetes were enriched in the mucosal microbiota of IBD patients. Disease type was the most influential factor in driving differences in the microbiota of both the mucosa and the lamina propria phagocytes, irrespective of inflammation state o`r anatomic location. Crohn's disease and ulcerative colitis specimens showed similar patterns of increased inflammatory gene expression in phagocytes isolated from inflamed areas compared with those isolated from uninflamed regions. CONCLUSIONS: This pilot study shows the feasibility of using lamina propria phagocytes to characterize the microbiota in IBD patients. The approach used in this study can narrow the spectrum of potentially dysbiotic bacterial populations and clinically relevant gene expression signatures in IBD patients.


Assuntos
Colite Ulcerativa/microbiologia , Doença de Crohn/microbiologia , Disbiose/diagnóstico , Microbioma Gastrointestinal/imunologia , Imunidade Inata/genética , Fagócitos/microbiologia , Biópsia , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Doença de Crohn/imunologia , Doença de Crohn/patologia , DNA Bacteriano/isolamento & purificação , Disbiose/imunologia , Disbiose/microbiologia , Disbiose/patologia , Estudos de Viabilidade , Feminino , Microbioma Gastrointestinal/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Separação Imunomagnética , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Masculino , Tipagem Molecular/métodos , Fagócitos/metabolismo , Projetos Piloto , RNA Ribossômico 16S/genética
15.
Blood Adv ; 3(3): 406-418, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30733301

RESUMO

In normoxia, hypoxia-inducible transcription factors (HIFs) are rapidly degraded within the cytoplasm as a consequence of their prolyl hydroxylation by oxygen-dependent prolyl hydroxylase domain (PHD) enzymes. We have previously shown that hematopoietic stem and progenitor cells (HSPCs) require HIF-1 for effective mobilization in response to granulocyte colony-stimulating factor (G-CSF) and CXCR4 antagonist AMD3100/plerixafor. Conversely, HIF PHD inhibitors that stabilize HIF-1 protein in vivo enhance HSPC mobilization in response to G-CSF or AMD3100 in a cell-intrinsic manner. We now show that extrinsic mechanisms involving vascular endothelial growth factor receptor-2 (VEGFR2), via bone marrow (BM) endothelial cells, are also at play. PTK787/vatalanib, a tyrosine kinase inhibitor selective for VEGFR1 and VEGFR2, and neutralizing anti-VEGFR2 monoclonal antibody DC101 blocked enhancement of HSPC mobilization by FG-4497. VEGFR2 was absent on mesenchymal and hematopoietic cells and was detected only in Sca1+ endothelial cells in the BM. We propose that HIF PHD inhibitor FG-4497 enhances HSPC mobilization by stabilizing HIF-1α in HSPCs as previously demonstrated, as well as by activating VEGFR2 signaling in BM endothelial cells, which facilitates HSPC egress from the BM into the circulation.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Isoquinolinas/farmacologia , Inibidores de Prolil-Hidrolase/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ftalazinas/farmacologia , Piridinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Aging (Albany NY) ; 11(2): 401-422, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30654329

RESUMO

Caffeoylquinic acid (CQA) is a natural polyphenol with evidence of antioxidant and neuroprotective effects and prevention of deficits in spatial learning and memory. We studied the cognitive-enhancing effect of 3,4,5-tricaffeoylquinic acid (TCQA) and explored its cellular and molecular mechanism in the senescence-accelerated mouse prone 8 (SAMP8) model of aging and Alzheimer's disease as well as in human neural stem cells (hNSCs). Mice were fed with 5 mg/kg of TCQA for 30 days and were tested in the Morris water maze (MWM). Brain tissues were collected for immunohistochemical detection of bromodeoxyuridine (BrdU) to detect activated stem cells and newborn neurons. TCQA-treated SAMP8 exhibited significantly improved cognitive performance in MWM compared to water-treated SAMP8. TCQA-treated SAMP8 mice also had significantly higher numbers of BrdU+/glial fibrillary acidic protein (GFAP+) and BrdU+/Neuronal nuclei (NeuN+) cells in the dentate gyrus (DG) neurogenic niche compared with untreated SAMP8. In hNSCs, TCQA induced cell cycle arrest at G0/G1, actin cytoskeleton organization, chromatin remodeling, neuronal differentiation, and bone morphogenetic protein signaling. The neurogenesis promoting effect of TCQA in the DG of SAMP8 mice might explain the cognition-enhancing influence of TCQA observed in our study, and our hNSCs in aggregate suggest a therapeutic potential for TCQA in aging-associated diseases.


Assuntos
Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Ácido Quínico/análogos & derivados , Animais , Cálcio/metabolismo , Linhagem Celular , Humanos , Masculino , Memória/fisiologia , Camundongos , Camundongos Endogâmicos , Células-Tronco Neurais , Neurogênese/fisiologia , Ácido Quínico/farmacologia
17.
J Plast Surg Hand Surg ; 51(1): 27-37, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28218551

RESUMO

BACKGROUND AND AIM: Adequate velopharyngeal function and speech are main goals in the treatment of cleft palate. The objective was to investigate if there were differences in velopharyngeal competency (VPC) and hypernasality at age 5 years in children with unilateral cleft lip and palate (UCLP) operated on with different surgical methods for primary palatal repair. A secondary aim was to estimate burden of care in terms of received additional secondary surgeries and speech therapy. DESIGN: Three parallel group, randomised clinical trials were undertaken as an international multicentre study by 10 cleft teams in five countries: Denmark, Finland, Sweden, Norway, and the UK. METHODS: Three different surgical protocols for primary palatal repair were tested against a common procedure in the total cohort of 448 children born with a non-syndromic UCLP. Speech audio and video recordings of 391 children (136 girls, 255 boys) were available and perceptually analysed. The main outcome measures were VPC and hypernasality from blinded assessments. RESULTS: There were no statistically significant differences between the prevalences in the arms in any of the trials. VPC: Trial 1, A: 58%, B: 61%; Trial 2, A: 57%, C: 54%; Trial 3, A: 35%, D: 51%. No hypernasality: Trial 1, A: 54%, B: 44%; Trial 2, A: 47%, C: 51%; Trial 3, A: 34%, D: 49%. CONCLUSIONS: No differences were found regarding VPC and hypernasality at age 5 years after different methods for primary palatal repair. The burden of care in terms of secondary pharyngeal surgeries, number of fistulae, and speech therapy visits differed. TRIAL REGISTRATION: ISRCTN29932826.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Distúrbios da Fala/terapia , Insuficiência Velofaríngea/prevenção & controle , Pré-Escolar , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Feminino , Seguimentos , Humanos , Lactente , Internacionalidade , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Procedimentos de Cirurgia Plástica/efeitos adversos , Recuperação de Função Fisiológica , Medição de Risco , Distúrbios da Fala/etiologia , Distúrbios da Fala/fisiopatologia , Fonoterapia/métodos , Fatores de Tempo , Resultado do Tratamento , Insuficiência Velofaríngea/etiologia
18.
J Plast Surg Hand Surg ; 51(1): 38-51, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28218556

RESUMO

BACKGROUND AND AIM: Normal articulation before school start is a main objective in cleft palate treatment. The aim was to investigate if differences exist in consonant proficiency at age 5 years between children with unilateral cleft lip and palate (UCLP) randomised to different surgical protocols for primary palatal repair. A secondary aim was to estimate burden of care in terms of received additional secondary surgeries and speech therapy. DESIGN: Three parallel group, randomised clinical trials were undertaken as an international multicentre study by 10 cleft teams in five countries: Denmark, Finland, Norway, Sweden, and the UK. METHODS: Three different surgical protocols for primary palatal repair were tested against a common procedure in the total cohort of 448 children born with non-syndromic UCLP. Speech audio- and video-recordings of 391 children (136 girls and 255 boys) were available and transcribed phonetically. The main outcome measure was Percent Consonants Correct (PCC) from blinded assessments. RESULTS: In Trial 1, arm A showed statistically significant higher PCC scores (82%) than arm B (78%) (p = .045). No significant differences were found between prevalences in Trial 2, A: 79%, C: 82%; or Trial 3, A: 80%, D: 85%. Across all trials, girls achieved better PCC scores, excluding s-errors, than boys (91.0% and 87.5%, respectively) (p = .01). CONCLUSIONS: PCC scores were higher in arm A than B in Trial 1, whereas no differences were found between arms in Trials 2 or 3. The burden of care in terms of secondary pharyngeal surgeries, number of fistulae, and speech therapy visits differed. TRIAL REGISTRATION: ISRCTN29932826.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Distúrbios da Fala/terapia , Fonoterapia/métodos , Transtornos da Articulação/etiologia , Transtornos da Articulação/terapia , Pré-Escolar , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Feminino , Seguimentos , Humanos , Lactente , Internacionalidade , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Procedimentos de Cirurgia Plástica/efeitos adversos , Recuperação de Função Fisiológica , Distúrbios da Fala/etiologia , Medida da Produção da Fala , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do Tratamento
19.
Inflamm Bowel Dis ; 22(4): 976-83, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26963566

RESUMO

Colitis-associated cancer (CAC) can develop in patients with inflammatory bowel disease with long-term uncontrolled inflammation. The mutational history and tumor microenvironment observed in CAC patients is distinct from that observed in sporadic colon cancer and suggests a different etiology. Recently, much attention has been focused on understanding the cellular origin of cancer and the cancer stem cells, which is key to growth and progression. Cancer stem cells are often chemo-resistant making them attractive targets for improving patient outcomes. New techniques have rapidly been evolving allowing for a better understanding of the normal intestinal stem cell function and behavior in the niche. Use of these new technologies will be crucial to understanding cancer stem cells in both sporadic and CAC. In this review, we will explore emerging methods related to the study of normal and cancer stem cells in the intestine, and examine potential avenues of investigation and application to understanding the pathogenesis of CAC.


Assuntos
Colite/complicações , Neoplasias do Colo/patologia , Intestinos/patologia , Células-Tronco Neoplásicas/patologia , Animais , Neoplasias do Colo/etiologia , Humanos
20.
Sci Rep ; 5: 12584, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26223541

RESUMO

Orexins are neuropeptides that regulate the sleep-wake cycle and feeding behaviour. QRFP is a newly discovered neuropeptide which exerts similar orexigenic activity, thus playing an important role in energy homeostasis and regulation of appetite. The exact expression and signalling characteristics and physiological actions of QRFP and its receptor GPR103 are poorly understood. Alzheimer's disease (AD) patients experience increased nocturnal activity, excessive daytime sleepiness, and weight loss. We hypothesised therefore that orexins and QRFP might be implicated in the pathophysiology of AD. We report that the down-regulation of hippocampal orexin receptors (OXRs) and GPR103 particularly in the cornu ammonis (CA) subfield from AD patients suffering from early onset familial AD (EOFAD) and late onset familial AD (LOAD). Using an in vitro model we demonstrate that this downregulation is due to to Aß-plaque formation and tau hyper-phosphorylation. Transcriptomics revealed a neuroprotective role for both orexins and QRFP. Finally we provide conclusive evidence using BRET and FRET that OXRs and GPR103 form functional hetero-dimers to exert their effects involving activation of ERK1/2. Pharmacological intervention directed at the orexigenic system may prove to be an attractive avenue towards the discovery of novel therapeutics for diseases such as AD and improving neuroprotective signalling pathways.


Assuntos
Doença de Alzheimer/patologia , Receptores de Orexina/química , Adulto , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Peptídeos beta-Amiloides/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dimerização , Regulação para Baixo , Transferência Ressonante de Energia de Fluorescência , Células HEK293 , Hipocampo/metabolismo , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptores de Orexina/genética , Receptores de Orexina/metabolismo , Fragmentos de Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Tretinoína/farmacologia , Sulfato de Zinco/farmacologia , Proteínas tau/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA