Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-37059013

RESUMO

Covalent organic frameworks (COFs) are a burgeoning class of crystalline porous materials with unique properties and have been considered as a promising functional extraction medium in sample pretreatment. In this study, a new methacrylate-bonded COF (TpTh-MA) was well designed and synthesized via the aldehyde-amine condensation reaction, and the TpTh-MA was incorporated into poly (ethylene dimethacrylate) porous monolith by a facile polymerization reaction inside capillary to prepare a novel TpTh-MA monolithic column. The fabricated TpTh-MA monolithic column was characterized with scanning electron microscope, Fourier transform infrared spectrometer, X-ray diffraction, and N2 adsorption-desorption experiments. Then, the homogeneous porous structure, good permeability and high mechanical stability of TpTh-MA monolithic column was used as separation and enrichment media of capillary microextraction, which was coupled with high-performance liquid chromatography fluorescence detection for online enrichment and analysis of trace estrogens. The main experimental parameters influencing the extraction efficiency were systematically investigated. The adsorption mechanism for three estrogens was also explored and discussed based on hydrophobic effect, π-π affinity and hydrogen bonding interaction, which contributed to its strong recognition affinity to target compounds. The enrichment factors of the TpTh-MA monolithic column micro extraction method for the three estrogens were 107-114, indicating a significant preconcentration ability. Under optimal conditions, a new online analysis method was developed and exhibited good sensitivity and wide linearity range of 0.25-100.0 µg·L-1 with a coefficient of determination (R2) higher than 0.9990 and a low limit of detection with 0.05-0.07 µg·L-1. The method was successfully applied for online analysis of three estrogens of milk and shrimp samples and the recoveries obtained from spiking experiments were in range of 81.4-113% and 77.9-111%, with the relative standard deviations of 2.6-7.9% and 2.1-8.3% (n = 5), respectively. The results revealed the great potential for the application of the COFs-bonded monolithic column in the field of sample pretreatment.


Assuntos
Estruturas Metalorgânicas , Estrogênios , Polímeros/química , Cromatografia Líquida de Alta Pressão/métodos , Metacrilatos/química
2.
J Sep Sci ; 45(9): 1493-1501, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35157355

RESUMO

Covalent organic frameworks with tunable porous crystallinity and outstanding stability have exhibited fascinating pretreatment performance as ideal extraction media. Herein, the ß-ketoenamine-linked TpPa-1 synthesized by 1,3,5-triformylphloroglucinol and paraphenylenediamine was employed as the absorbent for online micro-solid phase extraction of trace bisphenols combined with high-performance liquid chromatography detection. A series of characterizations indicated that the TpPa-1 possessed large surface areas, high stability, and hydrophobicity. The main experimental parameters affecting the extraction efficiency were optimized in detail. Compared with four commercial sorbents, the TpPa-1 exhibited superior enrichment capacity for extracting bisphenols. Under the optimum conditions, the established method demonstrated a wide linear range and high sensitivity with the limit of detection ranging from 0.05-0.06 µg/L. Furthermore, the developed method was successfully applied to determine bisphenols in plastic samples. Bisphenol A was actually detected in a transparent box with a concentration of 0.31 µg/g, and the recoveries of the four bisphenols in the plastic samples were 80.5-116% with the relative standard deviation less than 9.2%. Such performance was attributed to recognition affinity, including the π-π affinity, hydrophobic effect, and hydrogen bond. These results demonstrated that TpPa-1 possessed great potential to be an excellent pretreatment medium for online separation and analysis of trace analytes in complex samples.


Assuntos
Estruturas Metalorgânicas , Compostos Benzidrílicos , Cromatografia Líquida de Alta Pressão , Estruturas Metalorgânicas/química , Fenóis , Plásticos , Extração em Fase Sólida/métodos
3.
Se Pu ; 40(2): 109-122, 2022 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-35080157

RESUMO

Imine covalent organic frameworks (I-COFs), including imine-linked COFs and hydrazone-linked COFs, are a new type of crystalline porous organic materials constructed by the condensation of organic monomers by the Schiff-base reaction. Because they are composed of lightweight elements linked by strong covalent bonds, I-COF materials possess the advantages of low skeleton density, large surface area, high porosity, abundant monomer species, controllable pore size, functionalized structure, diverse synthetic methods, excellent adsorption performance, outstanding physical and chemical stabilities, etc. In recent years, interest in the field of I-COFs has increased tremendously because of their exceptional performance and broad applications in gas storage, gas separation, catalysis, sensing, photoelectric materials, sample pretreatment, drug delivery, and other fields. To date, imine bonds are one of the most widely used covalent bonds in COFs, and represent one of the most important ways to obtain I-COFs with excellent chemical stabilities. The synthesis methods for I-COFs include solvothermal synthesis, microwave synthesis, mechanochemical grinding synthesis, and room-temperature synthesis methods. Solvothermal synthesis is the most extensively used method for the production of I-COFs with high specific surface areas and good thermal stabilities. The microwave synthesis method is conducive to the rapid synthesis of COFs in industry, providing a more time-saving, simpler, and safer route for large-scale preparation of I-COFs. The mechanochemical grinding synthesis of porous solids has gained importance as an alternative to conventional solvothermal synthesis, because the process is quick, environment-friendly, and potentially scalable. The room-temperature method is characterized by mild reaction conditions and rapid reactions. It is an energy-saving, economic, safe, and green synthesis method, which has emerged as a hot spot in the preparation of I-COFs in recent years. Research progress over the past years on the application of I-COFs in the field of materials science has undoubtedly established the basis of its application in analytical chemistry. Owing to the excellent physical and chemical properties of I-COF materials, they are suitable for use as separation and enrichment media for trace target compounds in complex samples. The high specific surface area and porosity, extended conjugate network skeleton, and π-electron-rich nature of the materials endow it with a high adsorption capacity. These materials are highly enriched in target analytes by π-π interactions, acid-base interactions, donor-acceptor interactions, hydrogen bonding, hydrophobic interactions, and other intermolecular interactions. Precise control of the microporous structure of I-COFs was obtained by controlling the chain length, geometric structure, doping elements, and substituent groups of the organic monomers. Selective enrichment of target trace substances was achieved by modifying the groups of I-COFs based on the principle of host guest adaptation, molecular sieving, or microporous filling effect. At present, research on the synthesis of I-COF materials is in the stage of rapid development, and many I-COFs with excellent properties and great application potential have been synthesized, allowing widespread application of I-COFs in sample pretreatment medium. This review summarizes the current state-of-the-art on the main types and synthetic methods of I-COFs, as well as the applications of I-COFs in solid-phase extraction, magnetic solid-phase extraction, dispersive solid-phase extraction, and solid-phase microextraction. The prospects of I-COFs in sample pretreatment are also presented.

4.
Nat Commun ; 12(1): 5919, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635651

RESUMO

Abnormal activation of epidermal growth factor receptor (EGFR) drives non-small cell lung cancer (NSCLC) development. EGFR mutations-mediated resistance to tyrosine-kinase inhibitors (TKIs) is a major hurdle for NSCLC treatment. Here, we show that F-box protein FBXL2 targets EGFR and EGFR TKI-resistant mutants for proteasome-mediated degradation, resulting in suppression of EGFR-driven NSCLC growth. Reduced FBXL2 expression is associated with poor clinical outcomes of NSCLC patients. Furthermore, we show that glucose-regulated protein 94 (Grp94) protects EGFR from degradation via blockage of FBXL2 binding to EGFR. Moreover, we have identified nebivolol, a clinically used small molecule inhibitor, that can upregulate FBXL2 expression to inhibit EGFR-driven NSCLC growth. Nebivolol in combination with osimertinib or Grp94-inhibitor-1 exhibits strong inhibitory effects on osimertinib-resistant NSCLC. Together, this study demonstrates that the FBXL2-Grp94-EGFR axis plays a critical role in NSCLC development and suggests that targeting FBXL2-Grp94 to destabilize EGFR may represent a putative therapeutic strategy for TKI-resistant NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas F-Box/genética , Neoplasias Pulmonares/genética , Glicoproteínas de Membrana/genética , Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Animais , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Receptores ErbB/genética , Receptores ErbB/metabolismo , Proteínas F-Box/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Nus , Nebivolol/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Análise de Sobrevida , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Int J Mol Sci ; 20(5)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866414

RESUMO

Cell⁻cell adhesion plays an important role in regulation of cell proliferation, migration, survival, and drug sensitivity. Metformin, a first line drug for type 2 diabetes, has been shown to possess anti-cancer activities. However, whether cell⁻cell adhesion affects metformin anti-cancer activity is unknown. In this study, Microscopic and FACS analyses showed that metformin induced cancer cell⁻cell adhesion exemplified by cell aggregation and anoikis under glucose restriction. Furthermore, western blot and QPCR analyses revealed that metformin dramatically upregulated integrin ß1 expression. Silencing of integrin ß1 significantly disrupted cell aggregation and reduced anoikis induced by metformin. Moreover, we showed that p53 family member ΔNp63α transcriptionally suppressed integrin ß1 expression and is responsible for metformin-mediated upregulation of integrin ß1. In summary, this study reveals a novel mechanism for metformin anticancer activity and demonstrates that cell⁻cell adhesion mediated by integrin ß1 plays a critical role in metformin-induced anoikis.


Assuntos
Glucose/farmacologia , Integrina beta1/genética , Integrina beta1/metabolismo , Metformina/farmacologia , Neoplasias/metabolismo , Anoikis , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Células HEK293 , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima
6.
Cardiovasc Res ; 115(1): 230-242, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107531

RESUMO

Aims: Long non-coding RNAs (lncRNAs) have been shown to regulate numerous processes in the human genome, but the function of these transcripts in vascular aging is largely unknown. We aim to characterize the expression of lncRNAs in endothelial aging and analyse the function of the highly conserved lncRNA H19. Methods and results: H19 was downregulated in endothelium of aged mice. In human, atherosclerotic plaques H19 was mainly expressed by endothelial cells and H19 was significantly reduced in comparison to healthy carotid artery biopsies. Loss of H19 led to an upregulation of p16 and p21, reduced proliferation and increased senescence in vitro. Depletion of H19 in aortic rings of young mice inhibited sprouting capacity. We generated endothelial-specific inducible H19 deficient mice (H19iEC-KO), resulting in increased systolic blood pressure compared with control littermates (Ctrl). These H19iEC-KO and Ctrl mice were subjected to hindlimb ischaemia, which showed reduced capillary density in H19iEC-KO mice. Mechanistically, exon array analysis revealed an involvement of H19 in IL-6 signalling. Accordingly, intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 were upregulated upon H19 depletion. A luciferase reporter screen for differential transcription factor activity revealed STAT3 as being induced upon H19 depletion and repressed after H19 overexpression. Furthermore, depletion of H19 increased the phosphorylation of STAT3 at TYR705 and pharmacological inhibition of STAT3 activation abolished the effects of H19 silencing on p21 and vascular cell adhesion molecule 1 expression as well as proliferation. Conclusion: These data reveal a pivotal role for the lncRNA H19 in controlling endothelial cell aging.


Assuntos
Doenças das Artérias Carótidas/metabolismo , Senescência Celular , Células Endoteliais/metabolismo , Isquemia/metabolismo , Músculo Esquelético/irrigação sanguínea , RNA Longo não Codificante/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/patologia , Estudos de Casos e Controles , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Células Endoteliais/patologia , Feminino , Membro Posterior , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Isquemia/genética , Isquemia/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neovascularização Fisiológica , Fosforilação , Placa Aterosclerótica , RNA Longo não Codificante/genética , Transdução de Sinais , Molécula 1 de Adesão de Célula Vascular/metabolismo
7.
Circ Genom Precis Med ; 11(11): e001907, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30571184

RESUMO

BACKGROUND: Cytokine responses to activation of innate immunity differ between individuals, yet the genomic and tissue-specific transcriptomic determinants of inflammatory responsiveness are not well understood. We hypothesized that tissue-specific mRNA and long intergenic noncoding RNA (lincRNA) induction differs between individuals with divergent evoked inflammatory responses. METHODS: In the GENE Study (Genetics of Evoked Response to Niacin and Endotoxemia), we performed an inpatient endotoxin challenge (1 ng/kg lipopolysaccharide [LPS]) in healthy humans. We selected individuals in the top (high responders) and bottom (low responders) extremes of inflammatory responses and applied RNA sequencing to CD14 monocytes (N=15) and adipose tissue (N=25) before and after LPS administration. RESULTS: Although only a small number of genes were differentially expressed at baseline, there were clear differences in the magnitude of the transcriptional response post-LPS between high and low responders, with a far greater number of genes differentially expressed by endotoxemia in high responders. Furthermore, tissue responses differed during inflammation, and we found a number of tissue-specific differentially expressed lincRNAs post-LPS, which we validated. Relative to nondifferentially expressed lincRNAs, differentially expressed lincRNAs were equally likely to be nonconserved as conserved between human and mouse, indicating that conservation is not a predictor of lincRNAs associated with human inflammatory pathophysiology. Differentially expressed genes also were enriched for signals with inflammatory and cardiometabolic disease in published genome-wide association studies. CTB-41I6.2 ( AC002091.1), a nonconserved human-specific lincRNA, is one of the top lincRNAs regulated by endotoxemia in monocytes, but not in adipose tissue. Knockdown experiments in THP-1 monocytes suggest that this lincRNA enhances LPS-induced interleukin 6 ( IL6) expression in monocytes, and we now refer to this as monocyte LPS-induced lincRNA regulator of IL6 ( MOLRIL6). CONCLUSIONS: We highlight mRNAs and lincRNAs that represent novel candidates for modulation of innate immune and metabolic responses in humans. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00953667.


Assuntos
Tecido Adiposo/imunologia , Endotoxemia , Regulação da Expressão Gênica/imunologia , Monócitos/imunologia , RNA Longo não Codificante , RNA Mensageiro , Tecido Adiposo/patologia , Animais , Endotoxemia/genética , Endotoxemia/imunologia , Endotoxemia/patologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Imunidade Inata/genética , Inflamação/genética , Inflamação/imunologia , Masculino , Camundongos , Monócitos/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/imunologia , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Análise de Sequência de RNA
9.
J Cell Biochem ; 119(6): 4945-4956, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29384218

RESUMO

FOSL1 is frequently overexpressed in multiple types of human cancers including invasive breast cancers and implicated in cancer invasion and metastasis. However, how FOSL1 is overexpressed in cancers remains to be elucidated. Several microRNAs (miRNAs) have been shown to target FOSL1 and are downregulated in human cancers. Here, we report that miR-130a is a novel FOSL1 targeting miRNA. Using gene expression microarray analysis, we found that FOSL1 is among the most up-regulated genes in cells transfected with miR-130a inhibitors. Transient transfection-immunoblot, RNA-immunoprecipitation, and luciferase reporter assays revealed that miR-130a directly targets FOSL1 mRNA at its 3'-UTR. Overexpression of miR-130a significantly reduced the levels of FOSL1 in invasive breast cancer MDA-MB-231 and Hs578T cell lines and suppresses their migration and invasion. This inhibition can be rescued by ectopic expression of miR-130a-resistant FOSL1. Interestingly, we show that overexpression of miR-130a increased the levels of tight-junction protein ZO-1 while inhibition of miR-130a reduced the levels of ZO-1. We further show that miR-130a expression is significantly reduced in cancer tissues from triple-negative breast cancer (TNBC) patients, correlating significantly with the upregulation of FOSL1 expression, compared to non-TNBC tissues. Together, our results reveal that miR-130a directly targets FOSL1 and suppresses the inhibition of ZO-1, thus inhibiting cancer cell migration and invasion, in TNBCs.


Assuntos
Movimento Celular , Regulação Neoplásica da Expressão Gênica , MicroRNAs/biossíntese , Proteínas Proto-Oncogênicas c-fos/biossíntese , RNA Neoplásico/biossíntese , Neoplasias de Mama Triplo Negativas/metabolismo , Regulação para Cima , Proteína da Zônula de Oclusão-1/biossíntese , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , MicroRNAs/genética , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-fos/genética , RNA Neoplásico/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteína da Zônula de Oclusão-1/genética
10.
Circ J ; 81(12): 1945-1952, 2017 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-28747613

RESUMO

BACKGROUND: Increased inflammatory activity destabilizes the atherosclerotic lesion and may lead to atherothrombosis and symptomatic cardiovascular disease. Co-stimulatory molecules, such as CD137, are key regulators of inflammation, and CD137 activity regulates inflammation in experimental atherosclerosis. Here, we hypothesized that CD137 activation promotes carotid artery inflammation and atherothrombosis.Methods and Results:In a model of inducible atherothrombosis with surgical ligation of the right carotid artery and a subsequent placement of a polyethene cuff, elevated levels of CD137 and CD137 ligand mRNA in atherothrombotic vs. non-atherothrombotic murine carotid lesions was observed. Mice treated with the CD137 agonistic antibody 2A showed signs of increased inflammation in the aorta and a higher proportion of CD8+T cells in spleen and blood. In carotid lesions of 2A-treated mice, significantly higher counts of CD8+and major histocompatibility (MHC)-class II molecule I-Ab+cells were observed. Treatment with the CD137 agonistic antibody 2A did not significantly affect the atherothrombosis frequency in 16-week-old mice in this model. CONCLUSIONS: Levels of CD137 and CD137 ligand mRNA were higher in advanced atherosclerotic disease compared to control vessels, and treatment with the CD137 agonistic antibody 2A, in a murine model for inducible atherothrombosis promoted vascular inflammation, but had no significant effect on atherothrombosis frequency at this early disease stage.


Assuntos
Anticorpos Monoclonais/farmacologia , Artérias Carótidas/efeitos dos fármacos , Inflamação/induzido quimicamente , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Artérias Carótidas/patologia , Trombose das Artérias Carótidas , Camundongos , RNA Mensageiro/análise , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética
11.
Front Physiol ; 8: 429, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670289

RESUMO

Multiple research groups have started to uncover the complex genetic and epigenetic machinery necessary to maintain cardiovascular homeostasis. In particular, the key contribution of non-coding RNAs (ncRNAs) in regulating gene expression has recently received great attention. Aneurysms in varying locations of the aorta are defined as permanent dilations, predisposing to the fatal consequence of rupture. The characteristic pathology of an aneurysm is characterized by progressive vessel wall dilation, promoted by dying vascular smooth muscle cells and limited proliferation, as well as impaired synthesis and degradation of extracellular matrix components, which at least partially is the result of transmural inflammation and its disruptive effect on vessel wall homeostasis. Currently no conservative pharmacological approach exists that could slow down aneurysm progression and protect from the risk of acute rupture. In the recent past, several non-coding RNAs (mainly microRNAs) have been discovered as being involved in aneurysm progression throughout varying locations of the aorta. Exploring ncRNAs as key regulators and potential therapeutic targets by using antisense oligonucleotide strategies could open up promising opportunities for patients in the near future. Purpose of this current review is to summarize current findings and novel concepts of perspectivly utilizing ncRNAs for future therapeutic and biomarker applications.

12.
Cell Death Dis ; 8(5): e2818, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28542133

RESUMO

Protein disulfide isomerase (PDI) involves cell survival and death. Whether PDI mediates mechanical stretch stress (SS) and/or advanced glycosylation end products (AGEs) -triggered simultaneous increases in proliferation and apoptosis of vascular smooth muscle cells (VSMCs) is unknown. Here, we hypothesized that different expression levels of PDI trigger completely opposite cell fates among the different VSMC subtypes. Mouse veins were grafted into carotid arteries of non-diabetic and diabetic mice for 8 weeks; the grafted veins underwent simultaneous increases in proliferation and apoptosis, which triggered vein graft arterializations in non-diabetic or atherosclerosis in diabetic mice. A higher rate of proliferation and apoptosis was seen in the diabetic group. SS and/or AGEs stimulated the quiescent cultured VSMCs, resulting in simultaneous increases in proliferation and apoptosis; they could induce increased PDI activation and expression. Both in vivo and in vitro, the proliferating VSMCs indicated weak co-expression of PDI and SM-α-actin while apoptotic or dead cells showed strong co-expression of both. Either SS or AGEs rapidly upregulated the expression of PDI, NOX1 and ROS, and their combination had synergistic effects. Inhibiting PDI simultaneously suppressed the proliferation and apoptosis of VSMCs, while inhibition of SM-α-actin with cytochalasin D led to increased apoptosis and cleaved caspases-3 but had no effect on proliferation. In conclusion, different expression levels of PDI in VSMCs induced by SS and/or AGEs triggered a simultaneous increase in proliferation and apoptosis, accelerated vein graft arterializations or atherosclerosis, leading us to propose PDI as a novel target for the treatment of vascular remodeling and diseases.


Assuntos
Apoptose , Aterosclerose/etiologia , Diabetes Mellitus Experimental/patologia , Produtos Finais de Glicação Avançada/toxicidade , Miócitos de Músculo Liso/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Estresse Mecânico , Veias/cirurgia , Animais , Apoptose/efeitos dos fármacos , Aterosclerose/patologia , Prótese Vascular , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/enzimologia , Inibidores Enzimáticos/farmacologia , Glicosilação , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , NADPH Oxidase 1 , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
13.
Hum Mol Genet ; 26(3): 637-649, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28053049

RESUMO

Coagulation factor XI (FXI) has become increasingly interesting for its role in pathogenesis of thrombosis. While elevated plasma levels of FXI have been associated with venous thromboembolism and ischemic stroke, its deficiency is associated with mild bleeding. We aimed to determine novel genetic and post-transcriptional plasma FXI regulators.We performed a genome-wide association study (GWAS) for plasma FXI levels, using novel data imputed to the 1000 Genomes reference panel. Individual GWAS analyses, including a total of 16,169 European individuals from the ARIC, GHS, MARTHA and PROCARDIS studies, were meta-analysed and further replicated in 2,045 individuals from the F5L family, GAIT2 and MEGA studies. Additional association with activated partial thromboplastin time (aPTT) was tested for the top SNPs. In addition, a study on the effect of miRNA on FXI regulation was performed using in silico prediction tools and in vitro luciferase assays.Three loci showed robust, replicating association with circulating FXI levels: KNG1 (rs710446, P-value = 2.07 × 10-302), F11 (rs4253417, P-value = 2.86 × 10-193), and a novel association in GCKR (rs780094, P-value = 3.56 ×10-09), here for the first time implicated in FXI regulation. The two first SNPs (rs710446 and rs4253417) also associated with aPTT. Conditional and haplotype analyses demonstrated a complex association signal, with additional novel SNPs modulating plasma FXI levels in both the F11 and KNG1 loci. Finally, eight miRNAs were predicted to bind F11 mRNA. Over-expression of either miR-145 or miR-181 significantly reduced the luciferase activity in cells transfected with a plasmid containing FXI-3'UTR.These results should open the door to new therapeutic targets for thrombosis prevention.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Moléculas de Adesão Celular/sangue , Cininogênios/genética , Receptores de Superfície Celular/sangue , Trombose/genética , Moléculas de Adesão Celular/genética , Simulação por Computador , Feminino , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Tempo de Tromboplastina Parcial , Polimorfismo de Nucleotídeo Único , Processamento de Proteína Pós-Traducional/genética , Receptores de Superfície Celular/genética , Trombose/sangue , Trombose/fisiopatologia
14.
Oncotarget ; 8(7): 11053-11062, 2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28035068

RESUMO

Otub1 regulates p53 stability and activity via non-canonical inhibition of UbcH5, the MDM2 cognate ubiquitin-conjugating enzyme (E2). However, whether Otub1 regulates MDMX stability and activity is not clear. Here we report that Otub1 also suppresses MDM2-mediated MDMX ubiquitination in cells and in vitro, independently of its deubiquitinating enzyme activity. Consequently, overexpression of Otub1 markedly stabilized MDMX and increased its levels, whereas knockdown of Otub1 reduced the levels of MDMX. Interestingly, MDMX induced by Otub1 can localize to mitochondria in addition to the cytosol, enhance p53 phosphorylation at S46 (p53S46P) and promote mitochondria-mediated apoptotic pathway. Knockdown of MDMX reduced Otub1-induced p53S46P, which was shown to be critical for p53's mitochondrial function and apoptotic activity. Furthermore, Otub1 promotes UV-irradiation-induced p53S46P and apoptosis, which can be significantly inhibited by MDMX depletion. Together, these results suggest that Otub1 stabilizes MDMX and promotes p53S46P and mitochondria-mediated apoptosis, providing an alternative mechanism of Otub1's role in apoptosis.


Assuntos
Apoptose/genética , Cisteína Endopeptidases/genética , Mitocôndrias/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas/genética , Apoptose/efeitos da radiação , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Cisteína Endopeptidases/metabolismo , Enzimas Desubiquitinantes , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Mitocôndrias/metabolismo , Proteínas Nucleares/metabolismo , Fosforilação/efeitos da radiação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina/genética , Serina/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação , Raios Ultravioleta
15.
Circ Res ; 120(4): 633-644, 2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-27895035

RESUMO

RATIONALE: In the search for markers and modulators of vascular disease, microRNAs (miRNAs) have emerged as potent therapeutic targets. OBJECTIVE: To investigate miRNAs of clinical interest in patients with unstable carotid stenosis at risk of stroke. METHODS AND RESULTS: Using patient material from the BiKE (Biobank of Karolinska Endarterectomies), we profiled miRNA expression in patients with stable versus unstable carotid plaque. A polymerase chain reaction-based miRNA array of plasma, sampled at the carotid lesion site, identified 8 deregulated miRNAs (miR-15b, miR-29c, miR-30c/d, miR-150, miR-191, miR-210, and miR-500). miR-210 was the most significantly downregulated miRNA in local plasma material. Laser capture microdissection and in situ hybridization revealed a distinct localization of miR-210 in fibrous caps. We confirmed that miR-210 directly targets the tumor suppressor gene APC (adenomatous polyposis coli), thereby affecting Wnt (Wingless-related integration site) signaling and regulating smooth muscle cell survival, as well as differentiation in advanced atherosclerotic lesions. Substantial changes in arterial miR-210 were detectable in 2 rodent models of vascular remodeling and plaque rupture. Modulating miR-210 in vitro and in vivo improved fibrous cap stability with implications for vascular disease. CONCLUSIONS: An unstable carotid plaque at risk of stroke is characterized by low expression of miR-210. miR-210 contributes to stabilizing carotid plaques through inhibition of APC, ensuring smooth muscle cell survival. We present local delivery of miR-210 as a therapeutic approach for prevention of atherothrombotic vascular events.


Assuntos
MicroRNAs/administração & dosagem , MicroRNAs/biossíntese , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/terapia , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/terapia , Estenose das Carótidas/metabolismo , Estenose das Carótidas/patologia , Estenose das Carótidas/terapia , Células Cultivadas , Estudos de Coortes , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Microdissecção e Captura a Laser/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/análise , Placa Aterosclerótica/patologia , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/prevenção & controle
16.
Arterioscler Thromb Vasc Biol ; 36(9): 1947-61, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27470516

RESUMO

OBJECTIVE: Key augmented processes in atherosclerosis have been identified, whereas less is known about downregulated pathways. Here, we applied a systems biology approach to examine suppressed molecular signatures, with the hypothesis that they may provide insight into mechanisms contributing to plaque stability. APPROACH AND RESULTS: Muscle contraction, muscle development, and actin cytoskeleton were the most downregulated pathways (false discovery rate=6.99e-21, 1.66e-6, 2.54e-10, respectively) in microarrays from human carotid plaques (n=177) versus healthy arteries (n=15). In addition to typical smooth muscle cell (SMC) markers, these pathways also encompassed cytoskeleton-related genes previously not associated with atherosclerosis. SYNPO2, SYNM, LMOD1, PDLIM7, and PLN expression positively correlated to typical SMC markers in plaques (Pearson r>0.6, P<0.0001) and in rat intimal hyperplasia (r>0.8, P<0.0001). By immunohistochemistry, the proteins were expressed in SMCs in normal vessels, but largely absent in human plaques and intimal hyperplasia. Subcellularly, most proteins localized to the cytoskeleton in cultured SMCs and were regulated by active enhancer histone modification H3K27ac by chromatin immunoprecipitation-sequencing. Functionally, the genes were downregulated by PDGFB (platelet-derived growth factor beta) and IFNg (interferron gamma), exposure to shear flow stress, and oxLDL (oxidized low-density lipoprotein) loading. Genetic variants in PDLIM7, PLN, and SYNPO2 loci associated with progression of carotid intima-media thickness in high-risk subjects without symptoms of cardiovascular disease (n=3378). By eQTL (expression quantitative trait locus), rs11746443 also associated with PDLIM7 expression in plaques. Mechanistically, silencing of PDLIM7 in vitro led to downregulation of SMC markers and disruption of the actin cytoskeleton, decreased cell spreading, and increased proliferation. CONCLUSIONS: We identified a panel of genes that reflect the altered phenotype of SMCs in vascular disease and could be early sensitive markers of SMC dedifferentiation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Autoantígenos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Doenças das Artérias Carótidas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas de Filamentos Intermediários/metabolismo , Proteínas com Domínio LIM/metabolismo , Proteínas dos Microfilamentos/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Placa Aterosclerótica , Citoesqueleto de Actina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Autoantígenos/genética , Proteínas de Ligação ao Cálcio/genética , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Artérias Carótidas/fisiopatologia , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/patologia , Doenças das Artérias Carótidas/fisiopatologia , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/metabolismo , Estudos de Casos e Controles , Desdiferenciação Celular , Células Cultivadas , Proteínas do Citoesqueleto/genética , Modelos Animais de Doenças , Regulação para Baixo , Estudos de Associação Genética , Humanos , Proteínas de Filamentos Intermediários/genética , Proteínas com Domínio LIM/genética , Masculino , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Pessoa de Meia-Idade , Músculo Liso Vascular/patologia , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/patologia , Neointima , Fenótipo , Interferência de RNA , Ratos Sprague-Dawley , Transdução de Sinais , Fatores de Tempo , Transfecção , Vasoconstrição
17.
Ann Transl Med ; 4(7): 144, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27162794

RESUMO

MicroRNAs play key roles in the regulation of diverse cellular processes and during cardiovascular disease development and progression, such as myocardial infarction (MI) and heart failure (HF). A recent manuscript by Shen and colleagues provided evidence that the miR-30-CSE-H2S axis contributes to the protection against cardiomyocyte ischemic injury by regulating hydrogen sulfide (H2S) production. Inhibition of the miR-30 family after MI injury offers potential therapeutic value to 'keep our heart going on'. As this study highlights miRNAs as promising future therapeutic targets, their translational applicability to utilization in humans needs to be viewed with caution.

18.
Oncotarget ; 7(13): 16217-26, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26908445

RESUMO

A number of ribosomal proteins (RPs) have been shown to play a critical role in coordinating ribosome biogenesis with cell growth and proliferation by suppressing MDM2 to induce p53 activation. While how the MDM2-p53 pathway is regulated by multiple RPs is unclear, it remains to be interesting to identify additional RPs that can regulate this pathway. Here we report that ribosomal protein L4 (RPL4) directly interacts with MDM2 at the central acidic domain and suppresses MDM2-mediated p53 ubiquitination and degradation, leading to p53 stabilization and activation. Interestingly, overexpression of RPL4 promotes the binding of MDM2 to RPL5 and RPL11 and forms a complex with RPL5, RPL11 and MDM2 in cells. Conversely, knockdown of RPL4 also induces p53 levels and p53-dependent cell cycle arrest. This p53-dependent effect requires both RPL5 and RPL11, suggesting that depletion of RPL4 triggers ribosomal stress. Together, our results reveal that balanced levels of RPL4 are critical for normal cell growth and proliferation via regulating the MDM2-p53 loop.


Assuntos
Proliferação de Células/fisiologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Humanos
19.
Int J Clin Exp Med ; 8(8): 13657-69, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550311

RESUMO

AIM: To evaluate methodological quality and the extent of concordance among meta-analysis and/or systematic reviews on surgical interventions for gastric cancer (GC). METHODS: A comprehensive search of PubMed, Medline, EMBASE, the Cochrane library and the DARE database was conducted to identify the reviews comparing different surgical interventions for GC prior to April 2014. After applying included criteria, available data were summarized and appraised by the Oxman and Guyatt scale. RESULTS: Fifty six reviews were included. Forty five reviews (80.4%) were well conducted, with scores of adapted Oxman and Guyatt scale ≥ 14. The reviews differed in criteria for avoiding bias and assessing the validity of the primary studies. Many primary studies displayed major methodological flaws, such as randomization, allocation concealment, and dropouts and withdrawals. According to the concordance assessment, laparoscopy-assisted gastrectomy (LAG) was superior to open gastrectomy, and laparoscopy-assisted distal gastrectomy was superior to open distal gastrectomy in short-term outcomes. However, the concordance regarding other surgical interventions, such as D1 vs. D2 lymphadenectomy, and robotic gastrectomy vs. LAG were absent. CONCLUSION: Systematic reviews on surgical interventions for GC displayed relatively high methodological quality. The improvement of methodological quality and reporting was necessary for primary studies. The superiority of laparoscopic over open surgery was demonstrated. But concordance on other surgical interventions was rare, which needed more well-designed RCTs and systematic reviews.

20.
PLoS One ; 10(10): e0141375, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26488175

RESUMO

AIMS: This study was designed to demonstrate simultaneous increases in proliferation and apoptosis of vascular smooth muscle cells (VSMCs) leading to accelerated vein graft remodeling and to explore the underlying mechanisms. METHODS: Vein grafts were performed in non-diabetic and diabetic mice. The cultured quiescent VSMCs were subjected to mechanical stretch stress (SS) and/or advanced glycosylation end products (AGEs). Harvested vein grafts and treated VSMCs were used to detect cell proliferation, apoptosis, mitogen-activated protein kinases (MAPKs) activation and SM-α-actin expression. RESULTS: Significantly thicker vessel walls and greater increases in proliferation and apoptosis were observed in diabetic vein grafts than those in non-diabetic. Both SS and AGEs were found to induce different activation of three members of MAPKs and simultaneous increases in proliferation and apoptosis of VSMCs, and combined treatment with both had a synergistic effect. VSMCs with strong SM-α-actin expression represented more activated JNKs or p38MAPK, and cell apoptosis, while the cells with weak SM-α-actin expression demonstrated preferential activation of ERKs and cell proliferation. In contrast, inhibition of MAPKs signals triggered significant decreases in VSMC proliferation, and apoptosis. Treatment of the cells with RNA interference of receptor of AGEs (RAGE) also resulted in significant decreases in both proliferation and apoptosis. CONCLUSIONS: Increased pressure-induced SS triggers simultaneous increases in proliferation and apoptosis of VSMCs in the vein grafts leading to vein arterializations, which can be synergistically accelerated by high glucose-induced AGEs resulting in vein graft atherosclerosis. Either SS or AGEs and their combination induce simultaneous increases in proliferation and apoptosis of VSMCs via different activation of three members of MAPKs resulting from different VSMC subtypes classified by SM-α-actin expression levels.


Assuntos
Apoptose/fisiologia , Aterosclerose/fisiopatologia , Proliferação de Células/fisiologia , Diabetes Mellitus Experimental/fisiopatologia , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/fisiologia , Veias/fisiologia , Actinas/metabolismo , Animais , Aterosclerose/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Interferência de RNA/fisiologia , Transdução de Sinais/fisiologia , Estresse Mecânico , Veias/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA