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1.
J Biol Chem ; 298(7): 102106, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35671824

RESUMO

Neural stemness is suggested to be the ground state of tumorigenicity and pluripotent differentiation potential. However, the relationship between these cell properties is unclear. Here, by disrupting the neural regulatory network in neural stem and cancer cells and by serial transplantation of cancer cells, we show that tumorigenicity and pluripotent differentiation potential are coupled cell properties unified by neural stemness. We show that loss of neural stemness via inhibition of SETDB1, an oncoprotein with enriched expression in embryonic neural cells during vertebrate embryogenesis, led to neuronal differentiation with reduced tumorigenicity and pluripotent differentiation potential in neural stem and cancer cells, whereas enhancement of neural stemness by SETDB1 overexpression caused the opposite effects. SETDB1 maintains a regulatory network comprising proteins involved in developmental programs and basic cellular functional machineries, including epigenetic modifications (EZH2), ribosome biogenesis (RPS3), translation initiation (EIF4G), and spliceosome assembly (SF3B1); all of these proteins are enriched in embryonic neural cells and play active roles in cancers. In addition, SETDB1 represses the transcription of genes promoting differentiation and cell cycle and growth arrest. Serial transplantation of cancer cells showed that neural stemness, tumorigenicity, and pluripotent differentiation potential were simultaneously enhanced; these effects were accompanied by increased expression of proteins involved in developmental programs and basic machineries, including SETDB1 and the abovementioned proteins, as well as by increased alternative splicing events. These results indicate that basic machineries work together to define a highly proliferative state with pluripotent differentiation potential and also suggest that neural stemness unifies tumorigenicity and differentiation potential.


Assuntos
Carcinogênese , Diferenciação Celular , Histona-Lisina N-Metiltransferase , Células-Tronco Neurais , Células-Tronco Pluripotentes , Ciclo Celular , Desenvolvimento Embrionário , Flavonoides , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Pluripotentes/citologia
2.
Opt Express ; 31(26): 44385-44400, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178511

RESUMO

Wideband microwave absorbers, especially those with high optical transparency, are significantly used in civil and military fields. This paper proposes an ultra-wideband optically transparent metamaterial absorber (MMA) with causal optimal thickness and high angular stability. Based on the equivalent circuits model of the MMA, a genetic algorithm is adopted to identify the best circuit parameters that can realize broadband microwave absorption. High transparent indium tin oxide and poly-methyl methacrylate are utilized to realize the absorber. Optimization and simulation results show that the designed MMA presents a high microwave absorption above 90%, covering a wide frequency of 2.05-15.5 GHz with an impressive FBW of 153.3%. The proposed MMA exhibits extraordinary angular stability. For TM polarization, it can still maintain a fractional bandwidth (FBW) over 114.5% at an incidence angle of 70° and over 142% at an incidence angle of 60°, while the FBW of both TE polarization and TM polarization exceeds 150% when the incidence angle is below 45°. Furthermore, the proposed absorber has the advantages of high transparency and polarization insensitiveness. A prototype of the proposed MMA is fabricated and experimentally tested. The measured results are in excellent agreement with the optimized design and the full-wave simulation results, demonstrating its excellent performance. Most significantly, the overall thickness of the absorber is 0.102 λ at the lowest working frequency and only 1.08 times the causality-dictated minimum sample thickness. The MMA proposed herein provides methods to achieve high compatibility with wideband microwave absorption, optical transparency, and wide-angle incidence, thus enabling a wide range of applications in stealth, electromagnetic pollution reduction, and electromagnetic compatible facilities.

3.
J Biol Chem ; 297(5): 101275, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34619150

RESUMO

Previous studies suggested that cancer cells resemble neural stem/progenitor cells in regulatory network, tumorigenicity, and differentiation potential, and that neural stemness might represent the ground or basal state of differentiation and tumorigenicity. The neural ground state is reflected in the upregulation and enrichment of basic cell machineries and developmental programs, such as cell cycle, ribosomes, proteasomes, and epigenetic factors, in cancers and in embryonic neural or neural stem cells. However, how these machineries are concertedly regulated is unclear. Here, we show that loss of neural stemness in cancer or neural stem cells via muscle-like differentiation or neuronal differentiation, respectively, caused downregulation of ribosome and proteasome components and major epigenetic factors, including PRMT1, EZH2, and LSD1. Furthermore, inhibition of PRMT1, an oncoprotein that is enriched in neural cells during embryogenesis, caused neuronal-like differentiation, downregulation of a similar set of proteins downregulated by differentiation, and alteration of subcellular distribution of ribosome and proteasome components. By contrast, PRMT1 overexpression led to an upregulation of these proteins. PRMT1 interacted with these components and protected them from degradation via recruitment of the deubiquitinase USP7, also known to promote cancer and enriched in embryonic neural cells, thereby maintaining a high level of epigenetic factors that maintain neural stemness, such as EZH2 and LSD1. Taken together, our data indicate that PRMT1 inhibition resulted in repression of cell tumorigenicity. We conclude that PRMT1 coordinates ribosome and proteasome activity to match the needs for high production and homeostasis of proteins that maintain stemness in cancer and neural stem cells.


Assuntos
Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neurais/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , Ribossomos/metabolismo , Células A549 , Animais , Células Hep G2 , Humanos , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , Células-Tronco Neurais/patologia , Complexo de Endopeptidases do Proteassoma/genética , Proteína-Arginina N-Metiltransferases/genética , Proteínas Repressoras/genética , Ribossomos/genética
4.
J Immunol ; 204(5): 1334-1344, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953354

RESUMO

The IL1A and IL1B genes lie in close proximity on chromosome 2 near the gene for their natural inhibitor, IL1RN Despite diverse functions, they are all three inducible through TLR4 signaling but with distinct kinetics. This study analyzed transcriptional induction kinetics, chromosome looping, and enhancer RNA production to understand the distinct regulation of these three genes in human cells. IL1A, IL1B, and IL1RN were rapidly induced after stimulation with LPS; however, IL1B mRNA production was less inhibitable by iBET151, suggesting it does not use pause-release regulation. Surprisingly, chromatin looping contacts between IL1A and IL1B were highly intermingled, although those of IL1RN were distinct, and we focused on comparing IL1A and IL1B transcriptional pathways. Our studies demonstrated that enhancer RNAs were produced from a subset of the regulatory regions, that they were critical for production of the mRNAs, and that they bound a diverse array of RNA binding proteins, including p300 but not CBP. We, furthermore, demonstrated that recruitment of p300 was dependent on MAPKs. Integrator is another RNA binding protein recruited to the promoters and enhancers, and its recruitment was more dependent on NF-κB than MAPKs. We found that integrator and NELF, an RNA polymerase II pausing protein, were associated with RNA in a manner that facilitated interaction. We conclude that IL1A and IL1B share many regulatory contacts, signaling pathways, and interactions with enhancer RNAs. A complex of protein interactions with enhancer RNAs emphasize the role of enhancer RNAs and the overall structural aspects of transcriptional regulation.


Assuntos
Proteína p300 Associada a E1A/imunologia , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Lipopolissacarídeos/farmacologia , Monócitos/imunologia , Proteínas de Ligação a RNA/imunologia , Transcrição Gênica , Linhagem Celular , Proteína p300 Associada a E1A/genética , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1alfa/genética , Interleucina-1beta/genética , Proteínas de Ligação a RNA/genética , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/imunologia
5.
J Clin Immunol ; 41(8): 1853-1864, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34435264

RESUMO

PURPOSE: Chromosome 22q11.2 deletion syndrome is a common inborn error of immunity. The early consequences of thymic hypoplasia are low T cell numbers. Later in life, atopy, autoimmunity, inflammation, and evolving hypogammaglobulinemia can occur and the causes of these features are not understood. This study utilized an unbiased discovery approach to define alterations in histone modifications. Our goal was to identify durable chromatin changes that could influence cell behavior. METHODS: CD4 T cells and CD19 B cells underwent ChIP-seq analysis using antibodies to H3K4me3, H3K27ac, and H4ac. RNA effects were defined in CD4 T cells by RNA-seq. Serum cytokines were examined by Luminex. RESULTS: Histone marks of transcriptional activation at CD4 T cell promoters and enhancers were globally increased. The promoter activation signature had elements related to T cell activation and inflammation, concordant with effects seen in the transcriptome. B cells, in contrast, had a minimally altered epigenetic landscape in 22q11.2. Both cell types had an "edge" effect with markedly altered chromatin adjacent to the deletion. CONCLUSIONS: People with 22q11.2 deletion have altered CD4 T cell chromatin and a transcriptome concordant with the changes in the epigenome. These effects support a disease model where qualitative changes to T cells occur in addition to quantitative defects that have been well characterized. This study offers unique insight into qualitative differences in the T cells in 22q11.2 deletion, an aspect that has received limited attention.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Síndrome de DiGeorge/imunologia , Adolescente , Adulto , Linfócitos B/imunologia , Cromatina , Citocinas/sangue , Síndrome de DiGeorge/sangue , Feminino , Histonas , Humanos , Masculino , Adulto Jovem
6.
Phytother Res ; 35(4): 2057-2073, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33210367

RESUMO

Pinus yunnanensis pollen is rich in various physiological functions. However, whether the pine pollen wall (PW) plays a beneficial role in the body has not been studied. In this work, we have analyzed its effects on the metabolism and gut microbiota of mouse models of dyslipidemia. We found that the intake of pine PW prevents the liver pathologic changes and reduce the concentrations of TNF-α, IL-6, TC, and high-density lipoprotein cholesterol. Moreover, it can regulate bile acid and fat metabolism, SCFAs content, and the structure of the gut microbiota. According to the change of carbohydrate metabolites, we speculated that cellulose should be the main component to play the above beneficial role, and sporopollenin cannot be utilized in the intestine. Therefore, we consider this study of great significance as it gives a description of biological effects of the pine PW and paves the road to its use in health products.


Assuntos
Biomarcadores , Dislipidemias , Microbioma Gastrointestinal , Pinus , Animais , Masculino , Camundongos , Biomarcadores/metabolismo , Dislipidemias/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos , Pinus/química
7.
Allergy ; 74(12): 2449-2460, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31267532

RESUMO

BACKGROUND: Germline-encoded innate immune pattern recognition receptors (PRR) are expressed at epithelial surfaces and modulate epithelial defenses. Evidence suggests that stimulation of the Toll-like receptor (TLR) family of PRR may regulate epithelial barrier integrity by upregulating tight junction (TJ) complex protein expression, but it is not known whether this mechanism is utilized in esophageal epithelial cells. TJ complex proteins maintain intact barrier function and are dysregulated in atopic disorders including eosinophilic esophagitis. METHODS: Pattern recognition receptors expression was assessed in EoE and control primary esophageal epithelial cells, demonstrating robust expression of TLR2 and TLR3. The three-dimensional air-liquid interface culture (ALI) model was used to test whether TLR2 or TLR3 stimulation alters epithelial barrier function using an in vitro model of human epithelium. Transepithelial electrical resistance (TEER) and FITC-Dextran permeability were evaluated to assess membrane permeability. ALI cultures were evaluated by histology, immunohistochemistry, Western blotting, and chromatin immunoprecipitation (ChIP). RESULTS: TLR3 stimulation did not change TEER in the ALI model. TLR2 stimulation increased TEER (1.28- to 1.31-fold) and decreased paracellular permeability to FITC-Dextran, and this effect was abolished by treatment with anti-TLR2 blocking antibody. TJ complex proteins claudin-1 and zonula occludens-1 were upregulated following TLR2 stimulation, and ChIP assay demonstrated altered histone 4 acetyl binding at the TJP1 enhancer and CLDN1 enhancer and promoter following zymosan treatment, implying the occurrence of durable chromatin changes. CONCLUSIONS: Our findings implicate the TLR2 pathway as a potential regulator of esophageal epithelial barrier function and suggest that downstream chromatin modifications are associated with this effect.


Assuntos
Mucosa Esofágica/metabolismo , Receptor 2 Toll-Like/agonistas , Células Cultivadas , Células Epiteliais/metabolismo , Mucosa Esofágica/patologia , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Imunofenotipagem , Receptores de Reconhecimento de Padrão/metabolismo , Junções Íntimas , Receptores Toll-Like/metabolismo
8.
Sensors (Basel) ; 19(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344862

RESUMO

D-dot sensors can realize the non-contact measurement of transient electric fields, which is widely applied to electromagnetic pulse (EMP) measurements with characteristics of the wide frequency band, high linearity, and good stability. In order to achieve accurate calibration of D-dot sensors in the laboratory environment, this paper proposed a new calibration method based on system identification. Firstly, the D-dot sensor can be considered as a linear time-invariant (LTI) system under corner frequency, thus its frequency response can be characterized by the transfer function of a discrete output error (OE) model. Secondly, based on the partial linear regression of the transfer function curve, the sensitivity coefficient of the D-dot sensor is obtained. By increasing the influence weight of low-frequency components, this proposed method has better calibration performance when the waveform is distorted in the time domain, and can artificially adapt to the operating frequency range of the sensor at the same time.

9.
J Sci Food Agric ; 99(2): 675-684, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29961985

RESUMO

BACKGROUND: Pine pollen, a kind of Chinese traditional medicine, is rich in unsaturated fatty acids. During its processing, it is often needed to break the sporoderm in order to increase the availability of some ingredients, which can cause lipid oxidation and the development of rancidity during storage. RESULTS: The primal peroxide value (PV) of ultra-high-temperature short-time sterilization sporoderm-broken pine pollen (UHT-PP) was much higher (over 15 times) than raw pine pollen (R-PP) and 60 Co-irradiation sterilization sporoderm-broken pine pollen (60 Co-PP). The PV of UHT-PP first increased and then decreased shortly after; however, PV of R-PP and 60 Co-PP remained almost unchanged during storage. The volatiles associated with rancidity in UHT-PP were found to be significantly higher than 60 Co-PP, especially hexanal (nearly 30 times) and hexanoic acid (about 2 times), and a multi-organoleptic sensor analyzer (electronic nose system) was able to differentiate these three kinds of samples when the output was subjected to discriminant function analysis. During storage (30 days), hexanal first increased and then decreased (at about 5 days), and hexanoic acid continuously increased for UHT-PP; however, no significant change was noted for R-PP or 60 Co-PP. UHT-PP has a greater surface area than 60 Co-PP, although same sporoderm-broken processes were applied. Antioxidants (flavone, carotenoid and tocopherols, sterol compounds) in 60 Co-PP were significantly (P ≤ 0.05, by Duncan's multiple range test) higher than that in UHT-PP, although not significantly different for total phenolics. CONCLUSIONS: Rancidity occurs more readily in UHT-PP than in R-PP and 60 Co-PP during storage, probably because significant lipid oxidation and antioxidant degradation occurred during the UHT sterilization sporoderm-broken processing of pine pollen. © 2018 Society of Chemical Industry.


Assuntos
Radioisótopos de Cobalto/química , Irradiação de Alimentos/métodos , Lipídeos/química , Pinus/química , Pólen/efeitos da radiação , Animais , Antioxidantes/análise , Manipulação de Alimentos , Temperatura Alta , Oxirredução , Pinus/efeitos da radiação , Pólen/química
10.
Eur J Clin Invest ; 47(9): 667-674, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28722105

RESUMO

BACKGROUND AND AIMS: This study aimed to investigate the relationship between circulating soluble C-X-C chemokine ligand 16 (CXCL16) levels and clinical characteristics of gallstone. METHODS: 93 subjects including 53 subjects with gallstone, 25 subjects with nonalcoholic fatty liver disease (NAFLD), and 40 control subjects were recruited. All gallstone subjects underwent ultrasounds to confirm the gallstone patients. Serum CXCL16 levels and other clinical and biochemical parameters in all subjects were obtained based on standard clinical examination methods. Liver tissues from patients with gallstone undergoing cholecystotomy and healthy subjects were also used to determine the hepatic CXCL16 profiles by IHC staining and real-time quantitative PCR. RESULTS: Serum CXCL16 levels were significantly increased in patients with gallstone and NAFLD as compared to healthy controls (P < 0·001). Hepatic CXCL16 mRNA and protein levels were also significantly increased in gallstone patients following with elevation of hepatic triglycerides and free fatty acid concentration, as compared to those in healthy subjects (P < 0·001). Otherwise, serum CXCL16 levels positively correlated with nonalcoholic fatty liver disease (NAFLD), alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase (GGT) and direct bilirubin (P < 0·05), but negatively with total protein and albumin after adjustment with age and gender. Multiple stepwise regression analyses indicated that CXCL16 was independently associated with AST, NAFLD and albumin (P < 0·05, respectively). CONCLUSIONS: Serum CXCL16 levels are significantly increased in patients with gallstone, and are independently associated with liver injury in Chinese population, suggesting that CXCL16 may be a biomarker of liver injury in subjects with gallstone or NAFLD.


Assuntos
Quimiocina CXCL16/genética , Cálculos Biliares/genética , Fígado/metabolismo , RNA Mensageiro/metabolismo , Adulto , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Povo Asiático , Aspartato Aminotransferases/metabolismo , Estudos de Casos e Controles , Quimiocina CXCL16/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Feminino , Cálculos Biliares/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Triglicerídeos/metabolismo , gama-Glutamiltransferase/metabolismo
11.
Clin Sci (Lond) ; 131(15): 1877-1893, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28559425

RESUMO

The aim of the present study is to explore the molecular mechanism of fibroblast growth factor 21 (FGF21) in protecting against diabetic cardiomyopathy (DCM). Streptozotocin/high-fat diet (STZ/HFD) was used to induced diabetes in FGF21-deficient mice and their wild-type littermates, followed by evaluation of the difference in DCM between the two genotypes. Primary cultured cardiomyocytes were also used to explore the potential molecular mechanism of FGF21 in the protection of high glucose (HG)-induced cardiomyocyte injury. STZ/HFD-induced cardiomyopathy was exacerbated in FGF21 knockout mice, which was accompanied by a significant reduction in cardiac AMP-activated protein kinase (AMPK) activity and paraoxonase 1 (PON1) expression. By contrast, adeno-associated virus (AAV)-mediated overexpression of FGF21 in STZ/HFD-induced diabetic mice significantly enhanced cardiac AMPK activity, PON1 expression and its biological activity, resulting in alleviated DCM. In cultured cardiomyocytes, treatment with recombinant mouse FGF21 (rmFGF21) counteracted HG-induced oxidative stress, mitochondrial dysfunction, and inflammatory responses, leading to increased AMPK activity and PON1 expression. However, these beneficial effects of FGF21 were markedly weakened by genetic blockage of AMPK or PON1. Furthermore, inactivation of AMPK also markedly blunted FGF21-induced PON1 expression but significantly increased HG-induced cytotoxicity in cardiomyocytes, the latter of which was largely reversed by adenovirus-mediated PON1 overexpression. These findings suggest that FGF21 ameliorates DCM in part by activation of the AMPK-PON1 axis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Arildialquilfosfatase/metabolismo , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/prevenção & controle , Fatores de Crescimento de Fibroblastos/fisiologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Cardiomiopatias Diabéticas/metabolismo , Progressão da Doença , Ativação Enzimática/fisiologia , Fatores de Crescimento de Fibroblastos/deficiência , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/farmacologia , Proteínas Klotho , Masculino , Proteínas de Membrana/fisiologia , Camundongos Knockout , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Transdução de Sinais/fisiologia
12.
Acta Biochim Biophys Sin (Shanghai) ; 49(6): 541-549, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28459937

RESUMO

Chemokine C-X-C ligand 16 (CXCL16), a single-pass Type I membrane protein belonging to the CXC chemokine family, is related to the inflammatory response in liver injury. In present study, we investigated the pathophysiological role of CXCL16, a unique membrane-bound chemokine, in acetaminophen (APAP)-induced hepatotoxicity in mice. Mice were injected with APAP, and blood and tissue samples were harvested at different time points. The serum high-mobility group box 1 and CXCL16 levels were quantified by sandwich immunoassays. The liver tissue sections were stained with hematoxylin-eosin or with dihydroethidium staining. The expressions of CXCL16 and other cytokines were examined by real-time polymerase chain reaction. Ly6-B, p-jun N-terminal kinase (p-JNK), and JNK expressions were measured by western blot analysis. Intracellular glutathione, reactive oxygen species, and malondialdehyde levels were also measured. APAP overdose increased hepatic CXCL16 mRNA and serum CXCL16 protein levels. CXCL16-deficient mice exhibited significantly less liver injury and hepatic necrosis, as well as a lower mortality than wild-type (WT) mice in response to APAP-overdose treatment. APAP elevated the production of oxidative stress and decreased mitochondrial respiratory chain activation in WT mice, which was strongly reversed in CXCL16-knockout mice. In addition, CXCL16 deficiency inhibited the neutrophil infiltration and the production of proinflammatory cytokines triggered by APAP-overdose treatment. Our study revealed that CXCL16 is a critical regulator of liver immune response to APAP-induced hepatotoxicity, thus providing a potential strategy for the treatment of drug-induced acute liver failure by targeting CXCL16.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Quimiocina CXCL16/deficiência , Inflamação/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Analgésicos não Narcóticos/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Quimiocina CXCL16/genética , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Inflamação/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Análise de Sobrevida
13.
J Immunol ; 192(7): 3057-67, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24567534

RESUMO

Noncoding RNAs have been implicated in the regulation of expression of numerous genes; however, the mechanism is not fully understood. We identified bidirectional, long noncoding RNAs upstream of the TNF gene using five different methods. They arose in a region where the repressors LRRFIP1, EZH2, and SUZ12 were demonstrated to bind, suggesting a role in repression. The noncoding RNAs were polyadenylated, capped, and chromatin associated. Knockdown of the noncoding RNAs was associated with derepression of TNF mRNA and diminished binding of LRRFIP1 to both RNA targets and chromatin. Overexpression of the noncoding RNAs led to diminished expression of TNF and recruitment of repressor proteins to the locus. One repressor protein, LRRFIP1, bound directly to the noncoding RNAs. These data place the noncoding RNAs upstream of TNF gene as central to the transcriptional regulation. They appear to serve as a platform for the assembly of a repressive complex.


Assuntos
Regulação da Expressão Gênica , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Fator de Necrose Tumoral alfa/genética , Sequência de Bases , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Técnicas de Silenciamento de Genes , Humanos , Células K562 , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Ligação Proteica , Interferência de RNA , Proteínas de Ligação a RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismo
14.
Kidney Blood Press Res ; 41(1): 108-18, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881856

RESUMO

BACKGROUND/AIMS: The mechanism by which angiotensin-converting enzyme inhibitors (ACEIs) attenuate renal fibrosis has not been fully uncovered. METHODS: Renal fibrosis in rats was triggered by unilateral ureteral obstruction (UUO) and treated with Enalapril. RESULTS: Enalapril attenuated renal fibrosis, as evidenced by the fibrosis scores (1.07±0.73 versus 2.18±0.75 for 200 mg/ml Enalapril versus control, p<0.01) of Enalapril-treated UUO rats compared to mock-treated UUO rats. The amelioration was mast cell dependent, as Enalapril exhibited no effects on mast cell-deficient Kit(wsh/wsh) mice developing renal fibrosis. We detected lower levels of transforming growth factor ß (TGF-ß) and alpha-smooth muscle actin (α-SMA, a fibroblast activation marker) in the kidney tissue of Enalapril-treated UUO rats relative to the control UUO rats. Enalapril-treated UUO rats exhibited far fewer mast cells infiltrating per area in the kidney tissue than the control UUO rats (8.00±0.65 versus 29.00±0.57, p<0.01). Electron microscopy images revealed that mast cell degranulation was inhibited by Enalapril treatment. Further, IgE-mediated passive cutaneous anaphylaxis demonstrated that Enalapril blocked mast cell degranulation in vivo. CONCLUSION: Enalapril attenuated renal fibrosis in UUO rats, possibly by a mechanism involving the suppression of mast cell degranulation.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Degranulação Celular/efeitos dos fármacos , Nefropatias/tratamento farmacológico , Nefropatias/patologia , Mastócitos/efeitos dos fármacos , Mastócitos/patologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Degranulação Celular/fisiologia , Fibrose , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
15.
J Cell Biochem ; 115(7): 1269-76, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24464651

RESUMO

The aberrant expression of microRNAs (miRNAs) has been found in various types of cancer. The present study found miR-20a was significantly up-regulated in prostate cancer compared with normal prostate tissues. Patients with a higher miR-20a expression had a Gleason score of 7-10 and shorter survival time. The transwell and wound healing assays revealed that blocking expression of miR-20a by miR-20a ASO suppresses the invasion and migration of PC-3 and DU145 cells in vitro and also inhibits tumor growth in vivo. Furthermore, we identified miR-20a directly targets the ABL family non-receptor tyrosine kinases ABL2 and negatively regulates the phosphorylation of its downstream gene p190RhoGAP. Knockdown of ABL2 promoted cell invasion and migration and we identified miR-20a-induced cell invasion and migration can be rescued by ABL2. In conclusion, our findings show that miR-20a significantly contributes to the progression of prostate cancer by targeting ABL2.


Assuntos
Movimento Celular/genética , MicroRNAs/genética , Invasividade Neoplásica/genética , Neoplasias da Próstata/patologia , Proteínas Tirosina Quinases/genética , Regiões 3' não Traduzidas/genética , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Ativadoras de GTPase/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Gradação de Tumores , Fosforilação , Próstata/citologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/mortalidade , Proteínas Tirosina Quinases/biossíntese , Proteínas Proto-Oncogênicas c-abl/biossíntese , Proteínas Proto-Oncogênicas c-abl/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno , Regulação para Cima
16.
J Hepatol ; 61(4): 825-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24882054

RESUMO

BACKGROUND & AIMS: Acetaminophen (APAP) overdose causes hepatic necrosis and acute liver injury by inducing mitochondrial dysfunction and damage. Although the biochemical pathways that mediate APAP-induced hepatotoxicity have been well studied, the body's defense mechanism to attenuate this disease remains elusive. This study investigated the roles of adiponectin, an adipocyte-secreted adipokine with pleiotropic protective effects against obesity-related metabolic dysfunction, in the pathogenesis of APAP-induced liver injury in mice. METHODS: Adiponectin knockout (ADN KO) and C57 wild type mice were treated with an overdose of APAP, followed by histological and biochemical evaluation of liver injury and activation of autophagy. The mechanism of adiponectin in APAP-induced hepatocytic toxicity was also explored in primary cultured hepatocytes. RESULTS: APAP overdose triggers a marked accumulation of adiponectin in injured liver tissues. ADN KO mice exhibit severely exacerbated mitochondrial dysfunction and damage, oxidative stress and necrosis and much higher mortality in response to APAP overdose, whereas these changes are reversed by a single injection of adiponectin. Mechanistically, adiponectin induces autophagosome formation by AMP-activated protein kinase (AMPK)-dependent activation of the Unc-51-like kinase 1, consequently leading to the removal of damaged mitochondria from hepatocytes. The protective effects of adiponectin against APAP-induced mitochondrial damage, oxidative stress and necrosis are abrogated by blockage of AMPK or pharmacological inhibition of autophagy. CONCLUSIONS: Our findings suggest that the APAP-induced accumulation of adiponectin in liver tissues serves as an adaptive mechanism to ameliorate hepatotoxicity by promoting autophagy-mediated clearance of damaged mitochondria. Adiponectin agonists may represent a promising therapy for the drug-induced acute liver failure.


Assuntos
Acetaminofen/toxicidade , Adiponectina/metabolismo , Doença Hepática Induzida por Substâncias e Drogas , Fígado/patologia , Mitocôndrias Hepáticas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Analgésicos não Narcóticos/toxicidade , Animais , Autofagia/fisiologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citoproteção , Overdose de Drogas/metabolismo , Hepatócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/metabolismo
17.
J Vasc Access ; : 11297298241245066, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581270

RESUMO

Peripherally inserted central catheters are widely used in patients with extensive burns, with the guidelines recommending insertion through unburned skin. This case report describes a patient who was burned over 88% of their surface area and suffered severe inhalation injury. For him, the popliteal vein was the only vein on unburned skin available for catheter catheterization. Based on evidence, we successfully placed a peripherally inserted central catheter through the popliteal vein under ultrasound while the patient was in the prone position and avoided associated complications.

18.
J Biol Chem ; 287(53): 44749-60, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23105097

RESUMO

FoxO1 transcription factor controls the glucose and lipid metabolism, as well as cell proliferation and stress response. Akt, activated by insulin and other growth factors, phosphorylates FoxO1 causing its nuclear export and activity suppression. In this manuscript, we show that IL-1ß, a pro-inflammatory cytokine, has the opposite effects on FoxO1. IL-1ß stimulation of primary rat hepatocytes and HEK293 cells overexpressing the IL-1ß receptor (293-IL-1RI) results in increased nuclear and cytosolic FoxO1 protein but not mRNA levels. IL-1ß stimulation also elevates the levels of a mutant FoxO1 that is resistant to Akt phosphorylation. This suggests that an Akt-independent mechanism is involved. Co-stimulation with insulin does not affect the IL-1ß induction of FoxO1. The IL-1ß effects on FoxO1 are counteracted, however, by the silencing or inhibition of neutral sphingomyelinase 2 (nSMase-2) using shRNAi, scyphostatin, or GW4869, as well as by the pharmacological inhibition of JNK and ERK. Reversely, the overexpression of nSMase-2 through adenovirus-mediated gene transfer potentiates, in a JNK- and ERK-dependent manner, the IL-1ß effects. We also show that transcription of insulin-like growth factor-binding protein-1 mRNA, which requires active FoxO1, is stimulated by IL-1ß and is suppressed by the inhibition of nSMase-2 and JNK. In conclusion, we propose that IL-1ß regulates FoxO1 activity through a novel nSMase-2-dependent pathway.


Assuntos
Ceramidas/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Interleucina-1beta/metabolismo , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/genética , Células HEK293 , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Interleucina-1beta/genética , Masculino , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Endogâmicos F344 , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo
19.
Int J Med Sci ; 10(13): 1868-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24324363

RESUMO

OBJECTIVE: To investigate the expression and correlation of transforming growth factor-ß1 (TGF-ß1) and fibroblast growth factor receptor 4 (FGFR4) in human hepatocellular carcinoma (HCC) and the relationship with clinicopathological features and prognosis. MATERIALS AND METHODS: The expression of TGF-ß1 and FGFR4 in 126 HCC samples was detected immunohistochemically. Combined with clinical postoperative follow-up data, the expression of TGF-ß1 and FGFR4 in HCC and the relationship with the prognosis of patients were analyzed by statistically. RESULTS: The positive expression rate of TGF-ß1 was 84.1% (106/126) in tumors, and that in peritumoral liver tissues was 64.3% (81/126); the positive expression rate of FGFR4 in tumors was 74.6% (94/126) and that in peritumoral liver tissues was 57.1% (72/126). The expression of TGF-ß1 and FGFR4 in the carcinoma tissues was significantly higher than that in peritumoral liver tissues (p < 0.05). Intratumoral TGF-ß1 and FGFR4 expression was associated with TNM stage (p < 0.05). TGF-ß1 and FGFR4 expression levels didn't significantly correlate with other clinicopathological parameters, including age, sex, tumor size, serum AFP level, tumor differentiation, lymph node metastasis, etc. (p > 0.05). TGF-ß1 expression was positively correlated with FGFR4 expression (r = 0.595, p < 0.05). Patients with positive FGFR4 or TGF-ß1 expression had shorter overall survival compared with negative expression (p < 0.05). CONCLUSIONS: The expression of TGF-ß1 and FGFR4 could make synergy on the occurrence and progression of HCC, and may be used as prognosis indicators for HCC patients.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico
20.
Indian J Biochem Biophys ; 50(2): 87-92, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23720881

RESUMO

To investigate the biological function of microRNA-34a (miR-34a) in bladder cancer, the expression of miR-34a was determined using quantitative real-time polymerase chain (qRT-PCR) reaction in 42 cases of bladder cancer. The relationship between the expression of miR-34a and development of bladder cancer was also studied. The mature mimics of miR-34a were chemically synthesized and transiently transfected into human bladder cancer T24 cells. The effects of miR-34a on apoptosis, cell cycle and proliferation in T24 cells were evaluated by flow cytometry and MTT, respectively. The results showed that the low expression rate of miR-34a was correlated with the malignancy and tumor size of bladder cancer. The up-regulation of miR-34a in T24 cells contributed to cell growth and cell cycle arrest, but not caspase-3 pathway. These findings suggest that the relative low expression of miRNA-34a might be involved in the tumorigenesis of bladder cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/biossíntese , MicroRNAs/fisiologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Adulto , Idoso , Apoptose , Biomarcadores Tumorais , Caspase 3/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Fatores de Tempo
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