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1.
Nat Commun ; 11(1): 4928, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004791

RESUMO

High-altitude adaptation of Tibetans represents a remarkable case of natural selection during recent human evolution. Previous genome-wide scans found many non-coding variants under selection, suggesting a pressing need to understand the functional role of non-coding regulatory elements (REs). Here, we generate time courses of paired ATAC-seq and RNA-seq data on cultured HUVECs under hypoxic and normoxic conditions. We further develop a variant interpretation methodology (vPECA) to identify active selected REs (ASREs) and associated regulatory network. We discover three causal SNPs of EPAS1, the key adaptive gene for Tibetans. These SNPs decrease the accessibility of ASREs with weakened binding strength of relevant TFs, and cooperatively down-regulate EPAS1 expression. We further construct the downstream network of EPAS1, elucidating its roles in hypoxic response and angiogenesis. Collectively, we provide a systematic approach to interpret phenotype-associated noncoding variants in proper cell types and relevant dynamic conditions, to model their impact on gene regulation.


Assuntos
Aclimatação/genética , Cromatina/metabolismo , Grupos Étnicos/genética , Redes Reguladoras de Genes , Modelos Genéticos , Altitude , Doença da Altitude/etnologia , Doença da Altitude/genética , Doença da Altitude/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Hipóxia Celular/genética , Células Cultivadas , Cromatina/genética , Sequenciamento de Cromatina por Imunoprecipitação , Resistência à Doença/genética , Feminino , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipóxia/genética , Hipóxia/metabolismo , Oxigênio/metabolismo , Polimorfismo de Nucleotídeo Único , Gravidez , Cultura Primária de Células , RNA-Seq , Elementos Reguladores de Transcrição/genética , Seleção Genética , Tibet/etnologia , Fatores de Transcrição/metabolismo , Sequenciamento Completo do Genoma
2.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(10): 757-764, 2020 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-33045788

RESUMO

Objective: To investigate the effect of RATEA16 scaffold on the proliferation of human umbilical vein endothelial cells (HUVEC) and the effect of new self-assembling peptide hydrogel (RATEA16) scaffold with vascular endothelial growth factor (VEGF) on promoting angiogenesis. Methods: RATEA16 hydrogel was prepared, then the injectability, microstructure, degradation, biocompatibility of RATEA16 hydrogel were determined. HUVEC were cultured with RATEA16 scaffold to detect cell morphology and proliferation. HUVEC were cultured on RATEA16 scaffold with VEGF for 24 h. The expression of VEGF-A, von Willebrand factor (vWF), matrix metalloproteinase-9 (MMP-9) and platelet endothelial cell adhesion molecule-1 (PECAM-1) were detected by using real-time PCR to evaluate the effects of the scaffold with VEGF system on HUVEC differentiation. Results: The sol-gel transition was completed under neutral condition (pH=7.4) adjusted by Tris-HCl solution. The hydrogel could be easily injected from a syringe. It presented a porous and interconnected internal structure and the porosity of the scaffold was (67.3±9.4)%. After 4 week degradation in vitro, the residual weight was still (82.354±0.006)%, which exhibited slow degradation. HUVEC grew well after being cultured in leach liquor of RATEA16 hydrogel for 24 h, and there was no significant difference in HUVEC cell viability compared with that of the control group (P>0.05). HUVEC encapsulated in RATEA16 hydrogel appeared round in shape and exhibited effectively continuous proliferation. When HUVEC were cultured on RATEA16 hydrogel with VEGF for 24 h, the formation of vascular-like structures was observed. The expression of VEGF-A and MMP-9 was 1.5-2.0 times that of control group, and vWF was 10 times and PECAM-1 was 55 times compared with that of the control group (P<0.05). Conclusions: The RATEA16 hydrogel used in this study could be prepared by simply adjusting pH to neutral. This hydrogel exhibited good biodegradability, slow degradation and injectability. HUVEC might attach and spread in RATEA16 scaffold. The RATEA16 scaffold with VEGF could promote angiogenic differentiation of HUVEC. The novel scaffold is expected to achieve the critical vascularization process in bone tissue regeneration.


Assuntos
Hidrogéis , Fator A de Crescimento do Endotélio Vascular , Células Endoteliais da Veia Umbilical Humana , Humanos , Peptídeos/farmacologia , Veias Umbilicais
3.
Folia Biol (Praha) ; 66(3): 104-110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33069189

RESUMO

Cancer development is a highly complicated process in which tumour growth depends on the development of its vascularization system. To support their own growth, tumour cells significantly modify their microenvironment. One of such modifications inflicted by tumours is stimulation of endothelial cell migration and proliferation. There is accumulating evidence that extracellular vesicles (EVs) secreted by tumour cells (tumour-derived EVs, TEVs) may be regarded as "messengers" with the potential for affecting the biological activities of target cells. Interaction of TEVs with different cell types occurs in an auto- and paracrine manner and may lead to changes in the function of the latter, e.g., promoting motility, proliferation, etc. This study analysed the proangiogenic activity of EVs derived from human pancreatic adenocarcinoma cell line (HPC-4, TEVHPC) in vitro and their effect in vivo on Matrigel matrix vascularization in severe combined immunodeficient (SCID) mice. TEVHPC enhanced proliferation of HPC-4 cells and induced their motility. Moreover, TEVHPC stimulated human umbilical vein endothelial cell (HUVEC) proliferation and migration in vitro. Additionally, TEVHPC influenced secretion of proangiogenic factors (IL-8, VEGF) by HUVEC cells and supported Matrigel matrix haemoglobinization in vivo. These data show that TEVs may support tumour propagation in an autocrine manner and may support vascularization of the tumour. The presented data are in line with the theory that tumour cells themselves are able to modulate the microenvironment via TEVs to maximize their growth potential.


Assuntos
Carcinoma Ductal Pancreático/patologia , Vesículas Extracelulares/patologia , Neoplasias Pancreáticas/patologia , Animais , Comunicação Autócrina , Divisão Celular , Linhagem Celular Tumoral , Quimiotaxia , Colágeno , Combinação de Medicamentos , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Laminina , Camundongos , Camundongos SCID , Transplante de Neoplasias , Neovascularização Patológica/etiologia , Proteoglicanas , RNA Mensageiro/biossíntese , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Clinics (Sao Paulo) ; 75: e1865, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935825

RESUMO

OBJECTIVES: Hypoxia leads to endothelial cell inflammation, apoptosis, and damage, which plays an important role in the complications associated with ischemic cardiovascular disease. As an oxidoreductase, p66Shc plays an important role in the regulation of reactive oxygen species (ROS) production and apoptosis. Ketamine is widely used in clinics. This study was designed to assess the potential protective effect of ketamine against hypoxia-induced injury in human umbilical vein endothelial cells (HUVECs). Moreover, we explored the potential mechanism by which ketamine protected against hypoxia-induced endothelial injury. METHODS: The protective effects of ketamine against hypoxia-induced injury was assessed using cell viability and adhesion assays, quantitative polymerase chain reaction, and western blotting. RESULTS: Our data showed that hypoxia reduced HUVEC viability, increased the adhesion between HUVECs and monocytes, and upregulated the expression of endothelial adhesion molecules at the protein and mRNA levels. Moreover, hypoxia increased ROS accumulation and upregulated p66Shc expression. Furthermore, hypoxia downregulated sirt1 expression in HUVECs. Alternatively, ketamine was shown to reverse the hypoxia-mediated reduction of cell viability and increase in the adhesion between HUVECs and monocytes, ameliorate hypoxia-induced ROS accumulation, and suppress p66Shc expression. Moreover, EX527, a sirt1 inhibitor, reversed the protective effects of ketamine against the hypoxia-mediated reduction of cell viability and increase in adhesion between HUVECs and monocytes. CONCLUSION: Ketamine reduces hypoxia-induced p66Shc expression and attenuates ROS accumulation via upregulating sirt1 in HUVECs, thus attenuating hypoxia-induced endothelial cell inflammation and apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Hipóxia , Ketamina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Estresse Oxidativo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Veias Umbilicais
5.
Medicine (Baltimore) ; 99(38): e22241, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32957369

RESUMO

BACKGROUND: Quercetin, a major flavonol, wildly exists in plantage, which has been reported to have an anti-apoptosis and anti-inflammation effects on vascular endothelial cells, but its underlying molecular mechanisms remain unclear. OBJECTIVE: The aim of this study was to investigate the mechanisms of how quercetin inhibits tumor necrosis factor alpha (TNF-α) induced human umbilical vein endothelial cells (HUVECs) apoptosis and inflammation. METHODS AND RESULTS: HUVECs were preconditioned with quercetin for 18 hours, and subsequently treated with TNF-α for 6 hours to induce apoptosis. The expression of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, ß-actin mRNA was then detected by RT-PCR. Flow cytometry was used to estimate the apoptosis rates, and the expression of activator protein 1 (AP-1) and nuclear factor kappa B (NF-κB) was measured by Western blot. TNF-α induced elevated apoptosis rates and upregulation of VCAM-1, ICAM-1, and E-selectin were meaningfully reduced in HUVECs by pretreatment with quercetin. In addition, quercetin also inhibited the activation of AP-1and NF-κB. CONCLUSION: Results indicate that quercetin could suppress TNF-α induced apoptosis and inflammation by blocking NF-κB and AP-1 signaling pathway in HUVECs, which might be one of the underlying mechanisms in treatment of coronary heart disease.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Inflamação/prevenção & controle , NF-kappa B/metabolismo , Quercetina/farmacologia , Fator de Transcrição AP-1/metabolismo , Regulação para Baixo , Selectina E/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo
6.
PLoS Comput Biol ; 16(9): e1007758, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881897

RESUMO

With the ever-increasing quality and quantity of imaging data in biomedical research comes the demand for computational methodologies that enable efficient and reliable automated extraction of the quantitative information contained within these images. One of the challenges in providing such methodology is the need for tailoring algorithms to the specifics of the data, limiting their areas of application. Here we present a broadly applicable approach to quantification and classification of complex shapes and patterns in biological or other multi-component formations. This approach integrates the mapping of all shape boundaries within an image onto a global information-rich graph and machine learning on the multidimensional measures of the graph. We demonstrated the power of this method by (1) extracting subtle structural differences from visually indistinguishable images in our phenotype rescue experiments using the endothelial tube formations assay, (2) training the algorithm to identify biophysical parameters underlying the formation of different multicellular networks in our simulation model of collective cell behavior, and (3) analyzing the response of U2OS cell cultures to a broad array of small molecule perturbations.


Assuntos
Biologia Computacional/métodos , Processamento de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Linhagem Celular Tumoral , Técnicas Citológicas , Árvores de Decisões , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos
7.
Nature ; 585(7826): 574-578, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939089

RESUMO

Epithelial organoids, such as those derived from stem cells of the intestine, have great potential for modelling tissue and disease biology1-4. However, the approaches that are used at present to derive these organoids in three-dimensional matrices5,6 result in stochastically developing tissues with a closed, cystic architecture that restricts lifespan and size, limits experimental manipulation and prohibits homeostasis. Here, by using tissue engineering and the intrinsic self-organization properties of cells, we induce intestinal stem cells to form tube-shaped epithelia with an accessible lumen and a similar spatial arrangement of crypt- and villus-like domains to that in vivo. When connected to an external pumping system, the mini-gut tubes are perfusable; this allows the continuous removal of dead cells to prolong tissue lifespan by several weeks, and also enables the tubes to be colonized with microorganisms for modelling host-microorganism interactions. The mini-intestines include rare, specialized cell types that are seldom found in conventional organoids. They retain key physiological hallmarks of the intestine and have a notable capacity to regenerate. Our concept for extrinsically guiding the self-organization of stem cells into functional organoids-on-a-chip is broadly applicable and will enable the attainment of more physiologically relevant organoid shapes, sizes and functions.


Assuntos
Homeostase , Intestinos/embriologia , Morfogênese , Organoides/embriologia , Tecidos Suporte , Animais , Padronização Corporal , Diferenciação Celular , Linhagem da Célula , Cryptosporidium parvum/patogenicidade , Células-Tronco Embrionárias Humanas/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Intestinos/citologia , Intestinos/parasitologia , Intestinos/patologia , Camundongos , Modelos Biológicos , Organoides/citologia , Organoides/parasitologia , Organoides/patologia , Regeneração , Medicina Regenerativa , Células-Tronco , Técnicas de Cultura de Tecidos/métodos , Engenharia Tecidual
8.
Cells ; 9(9)2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911794

RESUMO

All-trans-retinoic acid (atRA) is the essential derivative of vitamin A and is of interest due to its various biological key functions. As shown in the recent literature, atRA also plays a role in the failing heart during myocardial infarction, the leading cause of death globally. To date insufficient mechanistic information has been available on related hypoxia-induced cell damage and reperfusion injuries. However, it has been demonstrated that a reduction in cellular atRA uptake abrogates hypoxia-mediated cell and tissue damage, which may offer a new route for intervention. Consequently, in this study, the effect of the novel cardio-protective compound 5-methoxyleoligin (5ML) on cellular atRA uptake was tested in human umbilical-vein endothelial cells (HUVECs). For this purpose, a high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method was developed to assess intra-cellular levels of the active substance and corresponding levels of vitamin A and its derivatives, including potential cis/trans isomers. This work also focused on light-induced isomerization and the stability of biological sample material to ensure sample integrity and avoid biased conclusions. This study provides evidence of the inhibitory effect of 5ML on cellular atRA uptake, a promising step toward a novel therapy for myocardial infarction.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Oxigênio/metabolismo , Tretinoína/metabolismo , Hipóxia Celular , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lignanas/farmacologia
9.
PLoS One ; 15(8): e0234492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790760

RESUMO

Endothelial injury is a common manifestation in IgA nephropathy (IgAN). After the previous identification of the upregulated soluble fms-like tyrosine kinase-1 (sFlt-1) correlated with endothelial injury in IgAN, in the present study, we further explored the role of sFlt-1 in endothelial injury in IgAN. We enrolled 72 patients with IgAN and detected the sFlt-1 levels. The polymeric IgA1 (pIgA1) complexes were isolated from the pooled plasma samples of another 10 patients with IgAN. Apoptosis proteins were detected in cultured human umbilical vein endothelial cells (HUVECs) with the stimulation of recombinant sFlt-1 or the caspase-9 inhibitor Z-LEHD-FMK. We identified there were positive correlations between sFlt-1 and IgA-IgG complex as well as vWF levels in patients with IgAN. The sFlt-1 levels in HUVECs were significantly upregulated by pIgA1 complex derived from IgAN patients in a concentration-dependent manner. The proliferation ability of HUVECs was damaged when stimulated with sFlt-1 protein in a time- and dose- dependent manner. And the apoptosis rate was up-regulated significantly as the stimulation concentrations of sFlt-1 increased. We found sFlt-1 challenge could significantly increase the expression of vWF. In addition, sFlt-1 increased the levels of caspase-9, caspase-3, Bax and mitochondrial membrane potential; facilitated the release of cytochrome C from mitochondria to cytoplasma. In contrast, Z-LEHD-FMK attenuated high sFlt-1-induced HUVECs apoptosis. In conclusion, our study demonstrated that sFlt-1 expression was up-regulated by the challenge of pIgA1 complex derived from patients with IgAN. Furthermore, increased sFlt-1 facilitated human umbilical vein endothelial cells apoptosis via the mitochondrial-dependent pathway.


Assuntos
Endotélio Vascular/fisiopatologia , Glomerulonefrite por IGA/fisiopatologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/fisiologia , Adulto , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/fisiologia , Caspase 9/efeitos dos fármacos , Inibidores de Caspase/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Feminino , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Oligopeptídeos/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto Jovem
10.
Ecotoxicol Environ Saf ; 202: 110932, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800216

RESUMO

Adverse health effects arising from exposure to fine particulates have become a major concern. Angiogenesis is a vital physiological process for the growth and development of cells and structures in the human body, whereby excessive or insufficient vessel growth could contribute to pathogenesis of diseases. We therefore evaluated indirect effects of carbon black (CB) and inhalable airborne particles on the angiogenic ability of unexposed Human Umbilical Vein Endothelial Cells (HUVECs) by co-culturing HUVECs with pre-exposed Small Airway Epithelial Cells (SAECs). As endothelial cells are major components of blood vessels and potential targets of fine particles, we investigated if lung epithelial cells exposed to ambient PM2.5 surrogates could induce bystander effects on neighboring unexposed endothelial cells in an alveolar-capillary co-culture lung model. Epithelial exposure to CB at a non-toxic dose of 25 µg/mL reduced endothelial tube formation and cell adhesion in co-cultured HUVECs, and decreased expression of angiogenic genes in SAECs. Similarly, exposure of differentiated SAECs to PM2.5 surrogates reduced cell reproductive ability, adhesion and tube formation of neighboring HUVECs. This indicates epithelial exposure to CB and urban PM2.5 surrogates both compromised the angiogenic ability of endothelial cells through bystander effects, thereby potentially perturbing the ventilation-perfusion ratio and affecting lung function.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Testes de Toxicidade , Técnicas de Cocultura , Células Epiteliais , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Pulmão/metabolismo , Neovascularização Patológica , Fuligem
11.
Life Sci ; 258: 118156, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32735886

RESUMO

AIMS: Flavin adenine dinucleotide (FAD), participates in fatty acid ß oxidation as a cofactor, which has been confirmed to enhance SCAD activity and expression. However, the role of FAD on hypertensive vascular remodeling is unclear. In this study, we investigated the underlying mechanisms of FAD on vascular remodeling and endothelial homeostasis. MAIN METHODS: Morphological examination of vascular remodeling were analyzed with hematoxylin and eosin (HE) staining, Verhoeff's Van Gieson (EVG) staing, Dihydroethidium (DHE) staining and Sirius red staining. HUVECs apoptotic rate was detected by flow cytometry and HUVECs reactive oxygen species (ROS) was detected by DHE-probe. Enzymatic reactions were used to detect SCAD enzyme activity. The protein level was detected by Western Blots, the mRNA level was detected by quantitative real-time PCR. KEY FINDINGS: In vivo experiments, FAD significantly decreased blood pressure and ameliorated vascular remodeling by increasing SCAD expression, Nitric Oxide (NO) production and reducing ROS production. In vitro experiments, FAD protected against the tBHP induced injury in HUVEC, by increasing the activity of SCAD, increasing the elimination of free fatty acid (FFA), scavenging ROS, reducing apoptotic rate, thereby improving endothelial cell function. SIGNIFICANCE: FAD has a new possibility for preventing and treating hypertensive vascular remodeling.


Assuntos
Acil-CoA Desidrogenases/metabolismo , Ativadores de Enzimas/uso terapêutico , Flavina-Adenina Dinucleotídeo/uso terapêutico , Hipertensão/tratamento farmacológico , Remodelação Vascular/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Flavina-Adenina Dinucleotídeo/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Ratos Endogâmicos SHR , Ratos Wistar
12.
Nat Commun ; 11(1): 4271, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848153

RESUMO

Performing multi-color nanoscopy for extended times is challenging due to the rapid photobleaching rate of most fluorophores. Here we describe a new fluorophore (Yale-595) and a bio-orthogonal labeling strategy that enables two-color super-resolution (STED) and 3D confocal imaging of two organelles simultaneously for extended times using high-density environmentally sensitive (HIDE) probes. Because HIDE probes are small, cell-permeant molecules, they can visualize dual organelle dynamics in hard-to-transfect cell lines by super-resolution for over an order of magnitude longer than with tagged proteins. The extended time domain possible using these tools reveals dynamic nanoscale targeting between different organelles.


Assuntos
Corantes Fluorescentes , Microscopia de Fluorescência/métodos , Nanotecnologia/métodos , Organelas/metabolismo , Linhagem Celular , Corantes Fluorescentes/química , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Imageamento Tridimensional , Microscopia Confocal , Fotodegradação , Imagem com Lapso de Tempo
13.
Life Sci ; 258: 118106, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32682916

RESUMO

AIMS: Endothelial dysfunction is a hallmark of hypertension. Herein, we assessed the effect of quercetin, a common dietary antioxidant, on endothelial function of spontaneously hypertensive rats (SHRs), and investigated the underlying molecular mechanisms. MAIN METHODS: The Wistar-Kyoto (WKY) and SHR rats were administered vehicle (1% w/v methyl cellulose) or quercetin (10 mg/kg body weight) by oral gavage once a day for 6 weeks. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured with a tail-cuff system. Functional of rat mesenteric arterioles was assessed by the temperature-controlled myograph. A dose-response curve was generated by the cumulative addition of acetylcholine (ACh) or sodium nitroprusside (SNP). NO production in the culture medium was assessed by measuring the concentration of nitrite, a stable metabolite of NO, using a modified Griess reagent. KEY FINDINGS: Quercetin improved endothelial function and decreased blood pressure in SHRs. Endothelial autophagy, an important cellular homeostatic process, was increased in the early phase of treatment, and decreased in the late phase of treatment. Quercetin promoted autophagy in cultured endothelial cells under both normal and oxidative stress conditions. Pharmacological inhibition of autophagy aggravated endothelial dysfunction in quercetin-treated endothelial cells under oxidative stress, and attenuated the antihypertensive and endothelial protective effects of quercetin in SHRs. SIGNIFICANCE: Quercetin protects endothelial function in hypertensive rats through promotion of autophagy. Thus, autophagy could serve as a potential therapeutic target for hypertension.


Assuntos
Autofagia/efeitos dos fármacos , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Hipertensão/fisiopatologia , Quercetina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
14.
Life Sci ; 258: 118124, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32702443

RESUMO

AIMS: Ketogenic diet (KD) has been proposed to be an effective lifestyle intervention for metabolic syndrome. However, the effects of KD on hypertension have not been well investigated. The present study aimed to investigate the effects and underling mechanisms of KD on hypertension in spontaneously hypertensive rats (SHRs). MATERIALS AND METHODS: SHRs were subjected to normal diet or KD for 4 weeks, starting at the age of 10 weeks. Then, the blood pressure and vascular function were assessed. Next, the eNOS expression, inflammatory factors and relative signaling pathway were examined. Human umbilical vein endothelial cells were used to investigate the underlying mechanism account for the effect of ketone on inflammation and eNOS expression. KEY FINDINGS: Compared with the normal diet, KD was indicated to aggravate hypertension and impaire endothelium-dependent relaxation in mesenteric arteries of SHRs. eNOS and CD31 expression in mesenteric arteries were also significantly suppressed by KD. In addition, KD markedly increased the activation of NF-κB pathway and the expression of IL1-ß and TNF-α. In vitro, results showed that inhibition of NF-κB could rescue the adverse effects of ketone body and TGF-ß on eNOS expression and inflammation response. SIGNIFICANCE: Our study indicated that KD impaired endothelium-dependent relaxation in mesenteric arteries and aggravated the development of hypertension in SHRs, suggesting that it should be more cautious to apply KD into clinical application in hypertensive individuals.


Assuntos
Dieta Cetogênica , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Hipertensão/metabolismo , Hipertensão/patologia , NF-kappa B/metabolismo , Animais , Biomarcadores/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Corpos Cetônicos/metabolismo , Masculino , Artérias Mesentéricas/metabolismo , Artérias Mesentéricas/patologia , Óxido Nítrico Sintase Tipo III/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Ratos Endogâmicos SHR , Vasodilatação , Perda de Peso
15.
Cell Prolif ; 53(8): e12830, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32608556

RESUMO

OBJECTIVES: Skin serves as the major interface between the external environment and body which is liable to many kinds of injuries. Mesenchymal stem cell (MSC) therapy has been widely used and became a promising strategy. Pre-treatment with chemical agents, hypoxia or gene modifications can partially protect MSCs against injury, and the pre-treated MSCs show the improved differentiation, homing capacity, survival and paracrine effects regard to attenuating injury. The aim of this study was to investigate whether the exosomes from the educated MSCs contribute to accelerate wound healing process. MATERIALS AND METHODS: We extracted the exosomes from the two educated MSCs and utilized them in the cutaneous wound healing model. The pro-angiogenetic effect of exosomes on endothelial cells was also investigated. RESULTS: We firstly found that MSCs pre-treated by exosomes from neonatal serum significantly improved their biological functions and the effect of therapy. Moreover, we extracted the exosomes from the educated MSCs and utilized them to treat the cutaneous wound model directly. We found that the released exosomes from MSCs which educated by neonatal serum before had the more outstanding performance in therapeutic effect. Mechanistically, we revealed that the recipient endothelial cells (ECs) were targeted and the exosomes promoted their functions to enhance angiogenesis via regulating AKT/eNOS pathway. CONCLUSIONS: Our findings unravelled the positive effect of the upgraded exosomes from the educated MSCs as a promising cell-free therapeutic strategy for cutaneous wound healing.


Assuntos
Exossomos/metabolismo , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/fisiologia , Cicatrização/fisiologia , Animais , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Camundongos Endogâmicos C57BL , Pele/citologia
16.
Nat Commun ; 11(1): 3697, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728101

RESUMO

As the number of genomics datasets grows rapidly, sample mislabeling has become a high stakes issue. We present CrosscheckFingerprints (Crosscheck), a tool for quantifying sample-relatedness and detecting incorrectly paired sequencing datasets from different donors. Crosscheck outperforms similar methods and is effective even when data are sparse or from different assays. Application of Crosscheck to 8851 ENCODE ChIP-, RNA-, and DNase-seq datasets enabled us to identify and correct dozens of mislabeled samples and ambiguous metadata annotations, representing ~1% of ENCODE datasets.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Desequilíbrio de Ligação/genética , Bases de Dados de Ácidos Nucleicos , Genótipo , Células HEK293 , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Células K562 , Escore Lod , Anotação de Sequência Molecular
17.
Nat Commun ; 11(1): 3571, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678094

RESUMO

Pathogenic bacteria of the genus Bartonella can induce vasoproliferative lesions during infection. The underlying mechanisms are unclear, but involve secretion of an unidentified mitogenic factor. Here, we use functional transposon-mutant screening in Bartonella henselae to identify such factor as a pro-angiogenic autotransporter, called BafA. The passenger domain of BafA induces cell proliferation, tube formation and sprouting of microvessels, and drives angiogenesis in mice. BafA interacts with vascular endothelial growth factor (VEGF) receptor-2 and activates the downstream signaling pathway, suggesting that BafA functions as a VEGF analog. A BafA homolog from a related pathogen, Bartonella quintana, is also functional. Our work unveils the mechanistic basis of vasoproliferative lesions observed in bartonellosis, and we propose BafA as a key pathogenic factor contributing to bacterial spread and host adaptation.


Assuntos
Bartonella/patogenicidade , Neovascularização Patológica/metabolismo , Transdução de Sinais , Sistemas de Secreção Tipo V/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Virulência/metabolismo , Animais , Bartonella/classificação , Bartonella/genética , Proliferação de Células , Perfilação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/microbiologia , Humanos , Camundongos , Neovascularização Patológica/genética , Neovascularização Patológica/microbiologia , Domínios Proteicos , Sistemas de Secreção Tipo V/química , Sistemas de Secreção Tipo V/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Virulência/química , Fatores de Virulência/genética
18.
PLoS One ; 15(7): e0235793, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32634162

RESUMO

Extracellular vesicles (EVs) are small vesicles secreted from cells. They have crucial biological functions in intercellular communications and may even be biomarkers for cancer. The various methods used to isolate EVs from body fluid and cell culture supernatant have been compared in prior studies, which determined that the component yield and physical properties of isolated EVs depend largely on the isolation method used. Several novel and combined methods have been recently developed, which have not yet been compared to the established methods. Therefore, the purpose of this study is to compare the physical and functional differences in EVs isolated using a differential centrifugation method, the precipitation-based Invitrogen kit, the ExoLutE kit, and the Exodisc, of which the latter two were recently developed. We investigated the properties of EVs isolated from non-infected and Kaposi's sarcoma-associated herpesvirus-infected human umbilical vein endothelial cells using each method and determined the yields of DNA, RNA, and proteins using quantitative polymerase chain reaction and bicinchoninic acid assays. Additionally, we determined whether the biological activity of EVs correlated with the quantity or physical properties of the EVs isolated using different methods. We found that Exodisc was the most suitable method for obtaining large quantities of EVs, which might be useful for biomarker investigations, and that the EVs separated using Exodisc exhibited the highest complement activation activity. However, we also found that the functional properties of EVs were best maintained when differential centrifugation was used. Effective isolation is necessary to study EVs as tools for diagnosing cancer and our findings may have relevant implications in the field of oncology by providing researchers with data to assist their selection of a suitable isolation method.


Assuntos
Fracionamento Celular/métodos , Células Endoteliais/química , Vesículas Extracelulares/química , Biomarcadores/análise , Centrifugação/métodos , Precipitação Química , DNA/análise , Células Endoteliais/virologia , Vesículas Extracelulares/virologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/isolamento & purificação , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteínas/análise , RNA/análise
19.
Nat Commun ; 11(1): 3363, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620750

RESUMO

Studying emerging or neglected pathogens is often challenging due to insufficient information and absence of genetic tools. Dual RNA-seq provides insights into host-pathogen interactions, and is particularly informative for intracellular organisms. Here we apply dual RNA-seq to Orientia tsutsugamushi (Ot), an obligate intracellular bacterium that causes the vector-borne human disease scrub typhus. Half the Ot genome is composed of repetitive DNA, and there is minimal collinearity in gene order between strains. Integrating RNA-seq, comparative genomics, proteomics, and machine learning to study the transcriptional architecture of Ot, we find evidence for wide-spread post-transcriptional antisense regulation. Comparing the host response to two clinical isolates, we identify distinct immune response networks for each strain, leading to predictions of relative virulence that are validated in a mouse infection model. Thus, dual RNA-seq can provide insight into the biology and host-pathogen interactions of a poorly characterized and genetically intractable organism such as Ot.


Assuntos
Regulação Bacteriana da Expressão Gênica/imunologia , Interações Hospedeiro-Patógeno/imunologia , Doenças Negligenciadas/imunologia , Orientia tsutsugamushi/genética , Tifo por Ácaros/imunologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Genoma Bacteriano , Células Endoteliais da Veia Umbilical Humana , Humanos , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Sequências Repetitivas Dispersas/genética , Camundongos , Doenças Negligenciadas/microbiologia , Orientia tsutsugamushi/imunologia , Orientia tsutsugamushi/patogenicidade , Proteômica , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , RNA Bacteriano/metabolismo , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , RNA-Seq , Tifo por Ácaros/microbiologia , Transcrição Genética , Sequenciamento Completo do Exoma
20.
Int J Nanomedicine ; 15: 4151-4169, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606670

RESUMO

Purpose: Focused ultrasound (FUS) is a noninvasive method to produce thermal and mechanical destruction along with an immune-stimulatory effect against cancer. However, FUS ablation alone appears insufficient to generate consistent antitumor immunity. In this study, a multifunctional nanoparticle was designed to boost FUS-induced immune effects and achieve systemic, long-lasting antitumor immunity, along with imaging and thermal enhancement. Materials and Methods: PEGylated PLGA nanoparticles encapsulating astragalus polysaccharides (APS) and gold nanorods (AuNRs) were constructed by a simple double emulsion method, characterized, and tested for cytotoxicity. The abilities of PA imaging and thermal-synergetic ablation efficiency were analyzed in vitro and in vivo. The immune-synergistic effect on dendritic cell (DC) differentiation in vitro and the immune response in vivo were also evaluated. Results: The obtained APS/AuNR/PLGA-PEG nanoparticles have an average diameter of 255.00±0.1717 nm and an APS-loading efficiency of 54.89±2.07%, demonstrating their PA imaging capability and high biocompatibility both in vitro and in vivo. In addition, the as-prepared nanoparticles achieved a higher necrosis cell rate and induced apoptosis rate in an in vitro cell suspension assay, greater necrosis area and decreased energy efficiency factor (EEF) in an in vivo rabbit liver assay, and remarkable thermal-synergic performance. In particular, the nanoparticles upregulated the expression of MHC-II, CD80 and CD86 on cocultured DCs in vitro, followed by declining phagocytic function and enhanced interleukin (IL)-12 and interferon (INF)-γ production. Furthermore, they boosted the production of tumor necrosis factor (TNF)-α, IFN-γ, IL-4, IL-10, and IgG1 (P< 0.001) but not IgG2a. Immune promotion peaked on day 3 after FUS in vivo. Conclusion: The multifunctional APS/AuNR/PLGA-PEG nanoparticles can serve as an excellent synergistic agent for FUS therapy, facilitating real-time imaging, promoting thermal ablation effects, and boosting FUS-induced immune effects, which have the potential to be used for further clinical FUS treatment.


Assuntos
Astrágalo (Planta)/química , Neoplasias da Mama/terapia , Ouro/química , Nanopartículas Multifuncionais/química , Nanotubos/química , Polissacarídeos/química , Terapia por Ultrassom , Animais , Antígenos CD/metabolismo , Apoptose , Morte Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Células Dendríticas/citologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imunoglobulina G/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Camundongos Endogâmicos BALB C , Fagocitose , Técnicas Fotoacústicas , Poliésteres/síntese química , Poliésteres/química , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Coelhos , Nanomedicina Teranóstica , Fator A de Crescimento do Endotélio Vascular/metabolismo
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