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1.
Biochim Biophys Acta Mol Basis Dis ; 1867(5): 166096, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33524530

RESUMO

Previous reports revealed that mutation of mitochondrial inner-membrane located protein SFXN1 led to pleiotropic hematological and skeletal defects in mice, associated with the presence of hypochromic erythroid cell, iron overload in mitochondrion of erythroblast and the development of sideroblastic anemia (SA). However, the potential role of sfxn1 during erythrocyte differentiation and the development of anemia, especially the pathological molecular mechanism still remains elusive. In this study, the correlation between sfxn1 and erythroid cell development is explored through zebrafish in vivo coupled with human hematopoietic cells assay ex vivo. Both knockdown and knockout of sfxn1 result in hypochromic anemia phenotype in zebrafish. Further analyses demonstrate that the development of anemia attributes to the biosynthetic deficiency of hemoglobin, which is caused by the biosynthetic disorder of heme that associates with one­carbon (1C) metabolism process of mitochondrial branch in erythrocyte. Sfxn1 is also involved in the differentiation and maturation of erythrocyte in inducible human umbilical cord blood stem cells. In addition, we found that functional disruption of sfxn1 causes hypochromic anemia that is distinct from SA. These findings reveal that sfxn1 is genetically conserved and essential for the maturation of erythrocyte via facilitating the production of hemoglobin, which may provide a possible guidance for the future clinical treatment of sfxn1 mutation associated hematological disorders.

3.
EuroIntervention ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33528359

RESUMO

BACKGROUND: Intravascular optical coherence tomography (IVOCT) enables detailed plaque characterisation in-vivo, but visual assessment is time-consuming and subjective. AIMS: This study aims to develop and validate an automatic framework for IVOCT plaque characterisation using artificial intelligence (AI). METHODS: IVOCT pullbacks from 5 international centres were analysed in a corelab, annotating basic plaque components, inflammatory markers and other structures. A deep convolutional network with encoding-decoding architecture and pseudo-3D input was developed and trained using hybrid loss. The proposed network was integrated into commercial software to be externally validated on additional IVOCT pullbacks from three international corelabs, taking the consensus among corelabs as reference. RESULTS: Annotated images from 509 pullbacks (391 patients) were divided into 10,517 and 1,156 cross-sections for the training and testing datasets, respectively. Dice coefficient of the model was 0.906 for fibrous plaque, 0.848 for calcium and 0.772 for lipid in the testing dataset. Excellent agreement in plaque burden quantification was observed between the model and manual measurements (R2=0.98). In the external validation, the software correctly identified 518 out of 598 plaque regions from 300 IVOCT cross-sections, with a diagnostic accuracy of 97.6%[95%CI:93.4%-99.3%] in fibrous plaque, 90.5%[95%CI:85.2%-94.1%] in lipid and 88.5%[95%CI:82.4%-92.7%] in calcium. The median time required for analysis was 21.4 (18.6-25.0) seconds per pullback. CONCLUSIONS: A novel AI framework for automatic plaque characterisation in IVOCT was developed, providing excellent diagnostic accuracy in both internal and external validation. This model might reduce subjectivity in image interpretation and facilitate IVOCT quantification of plaque composition, with potential applications in research and IVOCT-guided PCI.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33129735

RESUMO

OBJECTIVES: This study sought to investigate nonculprit plaque characteristics in patients with ST-segment elevation myocardial infarction (STEMI) presenting with plaque erosion (PE) and plaque rupture (PR). Pancoronary vulnerability was considered at nonculprit sites: 1) the CLIMA study (NCT02883088) defined high-risk plaques with simultaneous presence of 4 optical coherence tomography (OCT) features (minimum lumen area <3.5 mm2; fibrous cap thickness [FCT] <75 µm; maximum lipid arc >180º; and macrophage accumulation); and 2) the presence of plaque ruptures or thin-cap fibroatheromas (TCFA). BACKGROUND: PE is a unique clinical entity associated with better outcomes than PR. There is limited evidence regarding pancoronary plaque characteristics of patients with culprit PE versus culprit PR. METHODS: Between October 2016 and September 2018, 523 patients treated by 3-vessel OCT at the time of primary percutaneous intervention were included with 152 patients excluded from final analysis. RESULTS: Overall, 458 nonculprit plaques were identified in 202 STEMI patients with culprit PE; and 1,027 nonculprit plaques were identified in 321 STEMI patients with culprit PR. At least 1 CLIMA-defined OCT nonculprit high-risk plaque was seen in 11.4% of patients with culprit PE, but twice as many patients were seen with culprit PR (25.2%; p < 0.001). This proportion was also seen when individual high-risk features were analyzed separately. When patients with PE were divided by a heterogeneous substrate (fibrous or lipid-rich plaque) underlying the culprit site, the prevalence of nonculprits with FCT <75 µm, macrophages, and TCFA showed a significant gradient from PE(Fibrous) to PElipid-rich plaque (LRP) to PR. Interestingly, nonculprit rupture was rarely found in patients with culprit PE(Fibrous) (1.9%), although it was exhibited with comparable prevalence in patients with culprit PE(LRP) (16.3%) versus PR (17.8%). Culprit PE predicted decreased pancoronary vulnerability independent of conventional risk factors. CONCLUSIONS: STEMI patients with culprit PE have a limited pancoronary vulnerability that may explain better outcomes in these patients than in STEMI patients with culprit PR.

5.
EuroIntervention ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33164894

RESUMO

AIMS: To test whether a non-stenting anti-thrombotic strategy was still effective at 4-year follow-up in patients enrolled in the EROSION study and to explore potential predictors of long-term prognosis. METHODS AND RESULTS: Out of 55 patients who completed 1-month follow-up, 52 patients finished 4-year follow-up. The median duration was 4.8 years (4.2 - 5.8 years). The majority of patients remained free from events, and all patients were free from hard endpoints (death, myocardial infarction, stroke, bypass surgery, or heart failure). Only 1 patient had gastrointestinal bleeding, and 11 patients underwent elective target lesion revascularization (TLR). Patients in the non-TLR group had more optical coherence tomography (OCT) thrombus reduction from baseline to 1 month; 95% patients in the non-TLR group versus 45% in the TLR group (p=0.001) met the primary endpoint (thrombus volume reduction >50%). Consistent with the OCT findings, angiographic results showed that the TLR group had less improvement in diameter stenosis (p=0.014) at 1 month compared with non-TLR group. CONCLUSIONS: Four-year follow-up findings reconfirmed the safety of an anti-thrombotic therapy without stenting for erosion-caused acute coronary syndrome. Patients with better response to anti-thrombotic therapy in the first month were less likely to require stent implantation during the next four years.

6.
Coron Artery Dis ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33060524

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the association of diabetes mellitus (DM) with neointimal formation after implantation of second-generation drug-eluting stent (DES) visualized by optical coherence tomography (OCT). METHODS: Patients with single de novo coronary artery disease treated with second-generation DES between June 2014 and June 2017 in our department underwent OCT examination at 1-year follow-up and were enrolled in this retrospective study. The primary end point was in-stent mean neointimal thickness (MNT), and secondary end points included uncovered stent strut, minimal lumen area (MLA), neointimal burden, neointimal hyperplasia (NIH) patterns and stent thrombosis (ST) after 1 year of OCT follow-up. RESULTS: A total of 68 patents with DM (DM group) and 216 patients without DM (non-DM group) were enrolled. At 1-year follow-up, the DM group compared with the non-DM group, showed: MNT [160 (85-245) µm vs. 120 (60-220) µm, P = 0.038] and neointimal burden [21.4 (8.3-30.1)% vs. 14.0 (5.7-26.1)%, P = 0.023] to be significantly increased. Concurrently, MLA [4.60 (3.53-6.06) mm vs. 5.76 (4.28-7.20) mm, P = 0. 0.002] was significantly reduced. Interestingly, the degree of uncovered struts (7.3 ± 7.1% vs. 7.7 ± 6.7%, P = 0.704), NIH patterns (P = 0.984), and ST (7.9% vs. 7.4%, P = 0.88) were comparable between the two groups. After propensity score matching, the MNT [160 (90-240) µm vs. 110 (60-220) µm, P = 0.048] and neointimal burden [21.4 (8.3-30.1)% vs. 15.4 (5.6-26.3)%, P = 0.044] remained significantly different in the DM compared to the non-DM group. CONCLUSION: DM leads to significant increase in MNT and neointimal burden even with second-generation DES, nevertheless stent strut coverage, ST and NIH characteristics remained comparable among the cohorts at 1-year.

7.
FASEB J ; 34(9): 11997-12008, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32738093

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) have the ability to self-renew and differentiate into various blood cells, thus playing an important role in maintenance of lifelong hematopoiesis. Brahma-related gene 1 (BRG1), which acts as the ATP subunit of mammalian SWI-SNF-related chromatin remodeling complexes, is involved in human acute myeloid leukemia and highly expresses in short-term HSPCs. But its role and regulatory mechanism for HSPC development have not yet been well established. Here, we generated a brg1 knockout zebrafish model using TALEN technology. We found that in brg1-/- embryo, the primitive hematopoiesis remained well, while definitive hematopoiesis formation was significantly impaired. The number of hemogenic endothelial cells was decreased, further affecting definitive hematopoiesis with reduced myeloid and lymphoid cells. During embryogenesis, the nitric oxide (NO) microenvironment in brg1-/- embryo was seriously damaged and the reduction of HSPCs could be partially rescued by a NO donor. Chromatin immunoprecipitation (ChIP) assays showed that BRG1 could bind to the promoter of KLF2 and trigger its transcriptional activity of NO synthase. Our findings show that Brg1 promotes klf2a expression in hemogenic endothelium and highlight a novel mechanism for HSPC formation and maintenance.

9.
J Biophotonics ; 13(6): e201960243, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32077244

RESUMO

Light-sheet fluorescence microscopy (LSFM) allows volumetric live imaging at high-speed and with low photo-toxicity. Various LSFM modalities are commercially available, but their size and cost limit their access by the research community. A new method, termed sub-voxel-resolving (SVR) light-sheet add-on microscopy (SLAM), is presented to enable fast, resolution-enhanced light-sheet fluorescence imaging from a conventional wide-field microscope. This method contains two components: a miniature add-on device to regular wide-field microscopes, which contains a horizontal laser light-sheet illumination path to confine fluorophore excitation at the vicinity of the focal plane for optical sectioning; an off-axis scanning strategy and a SVR algorithm that utilizes sub-voxel spatial shifts to reconstruct the image volume that results in a twofold increase in resolution. SLAM method has been applied to observe the muscle activity change of crawling C. elegans, the heartbeat of developing zebrafish embryo, and the neural anatomy of cleared mouse brains, at high spatiotemporal resolution. It provides an efficient and cost-effective solution to convert the vast number of in-service microscopes for fast 3D live imaging with voxel-super-resolved capability.

10.
Int Heart J ; 60(5): 1061-1069, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31484870

RESUMO

Plaque erosion (PE) is a significant substrate of acute coronary thrombosis. An improved ability to distinguish plaque phenotype in vivo among patients with ST-segment elevation myocardial infarction (STEMI) is of considerable interest because of the potential to formulate tailored treatment. This study assessed the plaque features and screened the circulating microRNAs (miRNAs) characteristically expressed in patients with PE compared with those with plaque rupture (PR). An miRNA microarray profile was generated in an initial cohort of eight STEMI patients with PE and eight clinically matched subjects with PR to select the circulating miRNAs with significant differences. miRNAs of interest were validated in a prospective cohort, and the plaque characteristics of enrolled patients were assessed by optical coherence tomography (OCT). Thirty culprit lesions were classified as PE (32.6%) and 46 as PR (50%). The main component of PE was fibrotic tissue, whereas the chief component of PR was lipids (P < 0.001). Thirty-four miRNAs were differentially expressed between the two groups; we validated five candidates and found that only the level of circulating miR-3667-3p exhibited significant discriminatory power in predicting the presence of PE (AUC = 0.767; P < 0.001). Our results show that high levels of circulating miR-3667-3p are closely related to PE in STEMI patients, which provides further evidence for PE pathophysiology and potential tailor treatment strategies.


Assuntos
MicroRNA Circulante/sangue , Trombose Coronária/diagnóstico por imagem , Placa Aterosclerótica/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Tomografia de Coerência Óptica/métodos , Idoso , Área Sob a Curva , Estudos de Casos e Controles , China , Angiografia Coronária/métodos , Trombose Coronária/mortalidade , Trombose Coronária/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/patologia , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Medição de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Estatísticas não Paramétricas , Análise de Sobrevida , Resultado do Tratamento
12.
EuroIntervention ; 15(5): 434-451, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31258132

RESUMO

This consensus document is the second of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near infrared spectroscopy (NIRS)-IVUS. Beyond guidance of stent selection and optimization of deployment, invasive imaging facilitates angiographic interpretation and may guide treatment in acute coronary syndrome. Intravascular imaging can provide additional important diagnostic information when confronted with angiographically ambiguous lesions and allows assessment of plaque morphology enabling identification of vulnerability characteristics. This second document focuses on useful imaging features to identify culprit and vulnerable coronary plaque, which offers the interventional cardiologist guidance on when to adopt an intracoronary imaging-guided approach to the treatment of coronary artery disease and provides an appraisal of intravascular imaging-derived metrics to define the haemodynamic significance of coronary lesions.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/cirurgia , Consenso , Angiografia Coronária , Vasos Coronários , Humanos , Tomografia de Coerência Óptica , Ultrassonografia de Intervenção
13.
Nat Biomed Eng ; 3(9): 729-740, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31110292

RESUMO

Extracellular microparticles (MPs) can function as drug-delivery vehicles for anticancer drugs. Here, we show that the softness of MPs derived from tumour-repopulating cells (TRCs) isolated from three-dimensional fibrin gels enhances the MPs' drug-delivery efficiency. We found that, compared with MPs derived from tumour cells cultured in conventional tissue-culture plastic, TRC-derived MPs intravenously injected in tumour-xenograft-bearing mice showed enhanced accumulation in tumour tissues, enhanced blood-vessel crossing and penetration into tumour parenchyma, and preferential uptake by highly tumorigenic TRCs. We also show that the cytoskeleton-related protein cytospin-A plays a critical role in the regulation of TRC-derived MP softness. The modulation of the mechanical properties of TRC-derived MPs could aid the efficiency of delivery of anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Micropartículas Derivadas de Células/química , Sistemas de Liberação de Medicamentos/métodos , Animais , Apoptose , Vasos Sanguíneos , Linhagem Celular Tumoral , Sobrevivência Celular , Citoesqueleto , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Tecido Parenquimatoso/irrigação sanguínea , Tecido Parenquimatoso/efeitos dos fármacos , Fosfoproteínas/metabolismo , Células RAW 264.7 , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Eur Heart J ; 40(31): 2566-2584, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31112213

RESUMO

This consensus document is the second of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near infrared spectroscopy (NIRS)-IVUS. Beyond guidance of stent selection and optimization of deployment, invasive imaging facilitates angiographic interpretation and may guide treatment in acute coronary syndrome. Intravascular imaging can provide additional important diagnostic information when confronted with angiographically ambiguous lesions and allows assessment of plaque morphology enabling identification of vulnerability characteristics. This second document focuses on useful imaging features to identify culprit and vulnerable coronary plaque, which offers the interventional cardiologist guidance on when to adopt an intracoronary imaging-guided approach to the treatment of coronary artery disease and provides an appraisal of intravascular imaging-derived metrics to define the haemodynamic significance of coronary lesions.


Assuntos
Síndrome Coronariana Aguda/diagnóstico por imagem , Angiografia Coronária/tendências , Doença da Artéria Coronariana/terapia , Intervenção Coronária Percutânea/efeitos adversos , Síndrome Coronariana Aguda/terapia , Adulto , Idoso , Estudos de Casos e Controles , Ensaios Clínicos como Assunto , Consenso , Angiografia Coronária/métodos , Doença da Artéria Coronariana/patologia , Tomada de Decisões , União Europeia/organização & administração , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/métodos , Placa Aterosclerótica/patologia , Valor Preditivo dos Testes , Ruptura/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Stents , Tomografia de Coerência Óptica/métodos , Ultrassonografia de Intervenção/métodos
15.
EuroIntervention ; 15(9): e771-e778, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30946013

RESUMO

AIMS: The aim of this study was to determine the prevalence and significance of plaque with a multilayered (ML) pattern in patients with acute coronary syndrome (ACS) versus stable angina pectoris (SAP) using OCT. METHODS AND RESULTS: Two hundred and four patients (144 ACS and 60 SAP) with OCT imaging of the culprit lesions before intervention were studied. ML plaques were identified by OCT as plaque with multiple layers of distinct optical signals. ML plaque was identified in 119 out of 204 (58.3%) patients. ML plaques were more frequently observed in SAP than ACS (75% vs 51.4%, p=0.001). Patients with prior myocardial infarction (MI) had a higher incidence of ML plaque compared with those without (74.4% vs 54.5%, p=0.024). ML plaque had a higher degree of luminal stenosis (p=0.006), longer lesion length (p=0.025), more complex lesion type (B2/C) (p<0.001) on angiography and non-significant larger plaque burden (p=0.07) on IVUS compared with those without an ML pattern. CONCLUSIONS: ML plaques, indicative of prior thrombosis, were frequently identified in patients with CAD, particularly more so in SAP and those with prior MI compared with ACS. The presence of an ML pattern is a marker of a greater extent and severity of CAD, suggesting a pathogenic link between plaque healing and lesion progression.


Assuntos
Síndrome Coronariana Aguda/patologia , Angina Estável/patologia , Placa Aterosclerótica/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Síndrome Coronariana Aguda/epidemiologia , Angina Estável/epidemiologia , Angiografia Coronária , Humanos , Infarto do Miocárdio , Placa Aterosclerótica/epidemiologia , Placa Aterosclerótica/patologia , Prevalência , Ultrassonografia de Intervenção
16.
Theranostics ; 9(2): 424-435, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809284

RESUMO

Tumorigenic cells, when facing a hostile environment, may enter a dormant state, leading to long-term tumor survival, relapse, and metastasis. To date, the molecular mechanism of tumor cell dormancy remains poorly understood. Methods: A soft, 3-dimentional (3D) fibrin gel culture system was used to mechanically select and grow highly malignant and tumorigenic melanoma tumor-repopulating cells (TRCs). We cultured control melanoma TRCs, TRCs with Sox2 knockdown, TRCs with Sox2 knockout, and a 2D control for in vitro and in vivo experiments. Western blotting, immunofluorescence, and flow cytometry analysis were performed to examine TRC dormancy and exit from dormancy. Results: Under a low-expression condition, we show that Sox2, a stemness molecule participates in dormancy regulation of highly tumorigenic cells that can repopulate a tumor (TRCs). Intriguingly, complete depletion of Sox2 via knockout results in dormancy exit and growth resumption of melanoma TRCs in culture and elevation of melanoma TRC apoptosis. Mice that are injected subcutaneously with Sox2-depleted melanoma TRCs do not form tumors and survive much longer than those injected with melanoma TRCs. We found that complete depletion of Sox2 promotes nuclear translocation of phosphorylated STAT3, where it binds to the p53 gene promoter, thus activating the p53-caspase3 cascade. Conclusion: These findings provide a novel insight into the role of the Sox2 gene in tumor cell stemness, tumor dormancy, and apoptosis.


Assuntos
Regulação Neoplásica da Expressão Gênica , Melanoma Experimental/patologia , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição SOXB1/metabolismo , Animais , Apoptose , Proliferação de Células , Camundongos , Recidiva Local de Neoplasia , Fatores de Transcrição SOXB1/deficiência
17.
Biochim Biophys Acta Mol Basis Dis ; 1865(6): 1273-1283, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30684641

RESUMO

Mutations in the photoreceptor cell-specific nuclear receptor gene Nr2e3 increased the number of S-cone photoreceptors in human and murine retinas and led to retinal degeneration that involved photoreceptor and non-photoreceptor cells. The mechanisms underlying these complex phenotypes remain unclear. In the hope of understanding the precise role of Nr2e3 in photoreceptor cell fate determination and differentiation, we generated a line of Nr2e3 knockout zebrafish using CRISPR technology. In these Nr2e3-null animals, rod precursors undergo terminal mitoses but fail to differentiate as rods. Rod-specific genes are not expressed and the outer segment (OS) fails to form. Formation and differentiation of cone photoreceptors is normal. Specifically, there is no increase in the number of UV-cone or S-cone photoreceptors. Laminated retinal structure is maintained. After normal development, L-/M-cones selectively degenerate, with progressive shortening of OS that starts at age 1 month. The amount of cone phototransduction proteins is concomitantly reduced, whereas UV- and S-cones have normal OS lengths even at age 10 months. In vitro studies show Nr2e3 synergizes with Crx and Nrl to enhance rhodopsin gene expression. Nr2e3 does not affect cone opsin expression. Our results extend the knowledge of Nr2e3's roles and have specific implications for the interpretation of the phenotypes observed in human and murine retinas. Furthermore, our model may offer new opportunities in finding treatments for enhanced S-cone syndrome (ESCS) and other retinal degenerative diseases.


Assuntos
Diferenciação Celular/genética , Mutação , Receptores Citoplasmáticos e Nucleares/genética , Células Fotorreceptoras Retinianas Cones/patologia , Degeneração Retiniana/genética , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Proteínas de Peixe-Zebra/genética , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Microscopia Eletrônica de Transmissão , Receptores Citoplasmáticos e Nucleares/metabolismo , Retina/embriologia , Retina/crescimento & desenvolvimento , Retina/ultraestrutura , Células Fotorreceptoras Retinianas Cones/metabolismo , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
18.
Autophagy ; 15(3): 453-465, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30205735

RESUMO

Macroautophagy/autophagy is an important intracellular mechanism for the maintenance of cellular homeostasis. Here we show that the CERKL (ceramide kinase like) gene, a retinal degeneration (RD) pathogenic gene, plays a critical role in regulating autophagy by stabilizing SIRT1. In vitro and in vivo, suppressing CERKL results in impaired autophagy. SIRT1 is one of the main regulators of acetylation/deacetylation in autophagy. In CERKL-depleted retinas and cells, SIRT1 is downregulated. ATG5 and ATG7, 2 essential components of autophagy, show a higher degree of acetylation in CERKL-depleted cells. Overexpression of SIRT1 rescues autophagy in CERKL-depleted cells, whereas CERKL loses its function of regulating autophagy in SIRT1-depleted cells, and overexpression of CERKL upregulates SIRT1. Finally, we show that CERKL directly interacts with SIRT1, and may regulate its phosphorylation at Ser27 to stabilize SIRT1. These results show that CERKL is an important regulator of autophagy and it plays this role by stabilizing the deacetylase SIRT1.


Assuntos
Autofagia/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Degeneração Retiniana/genética , Sirtuína 1/metabolismo , Proteínas de Peixe-Zebra/genética , Acetilação , Animais , Autofagossomos/metabolismo , Proteína 5 Relacionada à Autofagia/química , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 7 Relacionada à Autofagia/química , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Humanos , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Processamento de Proteína Pós-Traducional/genética , Retina/patologia , Epitélio Pigmentado da Retina/metabolismo , Retinite Pigmentosa/genética , Sirtuína 1/química , Sirtuína 1/genética , Regulação para Cima , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
19.
EuroIntervention ; 14(17): 1768-1775, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30277462

RESUMO

AIMS: This study aimed to evaluate the relationship between pre-infarction angina (PIA) and in vivo culprit lesion characteristics as assessed by intravascular optical coherence tomography (OCT) in patients with a first ST-segment elevation myocardial infarction (STEMI). METHODS AND RESULTS: A total of 305 consecutive patients with a first STEMI who underwent OCT imaging of culprit lesions during primary percutaneous coronary intervention (PCI) were prospectively enrolled. OCT findings of the culprit plaque were compared between patients with (n=206) and without PIA (n=99). Patients with PIA showed lower rates of thin-cap fibroatheroma (TCFA) (62.6% vs. 80.8%, p=0.001) and plaque rupture (56.8% vs. 72.7%, p=0.007), smaller maximum ruptured cavity areas (1.10±1.04 mm2 vs. 1.53±1.20 mm2, p=0.002), and more severe residual luminal narrowing (p=0.015) with a higher incidence of white residual thrombus (68.4% vs. 50.0%, p=0.003) at the culprit lesions than patients without PIA. No significant differences in clinical outcomes were observed at the one-year follow-up. CONCLUSIONS: In patients with a first STEMI, PIA was significantly associated with a lower incidence of TCFA and plaque rupture, a smaller ruptured cavity area, more white residual thrombi, and more severe lumen stenosis at the culprit lesions.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Placa Aterosclerótica , Infarto do Miocárdio com Supradesnível do Segmento ST , Angiografia Coronária , Humanos , Infarto , Tomografia de Coerência Óptica
20.
FASEB J ; 33(1): 696-710, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30044923

RESUMO

The proper development of atrioventricular (AV) valves is critical for heart morphogenesis and for the formation of the cardiac conduction system. Defects in AV valve development are the most common type of congenital heart defect. Cardiac troponin I ( ctnni), a structural and regulatory protein involved in cardiac muscle contraction, is a subunit of the troponin complex, but the functions and molecular mechanisms of ctnni during early heart development remain unclear. We created a knockout zebrafish model in which troponin I type 1b ( tnni1b) ( Tnni-HC, heart and craniofacial) was deleted using the clustered regularly interspaced short palindromic repeat/clustered regularly interspaced short palindromic repeat-associated protein system. In the homozygous mutant, the embryos showed severe pericardial edema, malformation of the heart tube, reduction of heart rate without contraction and with almost no blood flow, heart cavity congestion, and lack of an endocardial ring or valve leaflet, resulting in 88.8 ± 6.0% lethality at 7 d postfertilization. Deletion of tnni1b caused the abnormal expression of several markers involved in AV valve development, including bmp4, cspg2, has2, notch1b, spp1, and Alcam. Myocardial re-expression of tnni1b in mutants partially rescued the pericardial edema phenotype and AV canal (AVC) developmental defects. We further showed that tnni1b knockout in zebrafish and ctnni knockdown in rat h9c2 myocardial cells inhibited cardiac wnt signaling and that myocardial reactivation of wnt signaling partially rescued the abnormal expression of AVC markers caused by the tnni1b deletion. Taken together, our data suggest that tnni1b plays a vital role in zebrafish AV valve development by regulating the myocardial wnt signaling pathway.-Cai, C., Sang, C., Du, J., Jia, H., Tu, J., Wan, Q., Bao, B., Xie, S., Huang, Y., Li, A., Li, J., Yang, K., Wang, S., Lu, Q. Knockout of tnni1b in zebrafish causes defects in atrioventricular valve development via the inhibition of myocardial wnt signaling pathway.


Assuntos
Nó Atrioventricular/patologia , Embrião não Mamífero/patologia , Valvas Cardíacas/patologia , Miocárdio/patologia , Troponina I/antagonistas & inibidores , Via de Sinalização Wnt , Proteínas de Peixe-Zebra/antagonistas & inibidores , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados/embriologia , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Nó Atrioventricular/metabolismo , Sistemas CRISPR-Cas , Células Cultivadas , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Valvas Cardíacas/embriologia , Valvas Cardíacas/metabolismo , Miocárdio/metabolismo , Organogênese , Ratos , Troponina I/genética , Troponina I/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
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