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1.
J Biol Chem ; 298(5): 101938, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35429501

RESUMO

Mitogen-activated protein kinase phosphatase 1 (Mkp-1) KO mice produce elevated cytokines and exhibit increased mortality and bacterial burden following systemic Escherichia coli infection. To understand how Mkp-1 affects immune defense, we analyzed the RNA-Seq datasets previously generated from control and E. coli-infected Mkp-1+/+ and Mkp-1-/- mice. We found that E. coli infection markedly induced programmed death-ligand 1 (PD-L1) expression and that Mkp-1 deficiency further amplified PD-L1 expression. Administration of a PD-L1-neutralizing monoclonal antibody (mAb) to Mkp-1-/- mice increased the mortality of the animals following E. coli infection, although bacterial burden was decreased. In addition, the PD-L1-neutralizing mAb increased serum interferon (IFN)-γ and tumor necrosis factor alpha, as well as lung- and liver-inducible nitric oxide synthase levels, suggesting an enhanced inflammatory response. Interestingly, neutralization of IFN-α/ß receptor 1 blocked PD-L1 induction in Mkp-1-/- mice following E. coli infection. PD-L1 was potently induced in macrophages by E. coli and lipopolysaccharide in vitro, and Mkp-1 deficiency exacerbated PD-L1 induction with little effect on the half-life of PD-L1 mRNA. In contrast, inhibitors of Janus kinase 1/2 and tyrosine kinase 2, as well as the IFN-α/ß receptor 1-neutralizing mAb, markedly attenuated PD-L1 induction. These results suggest that the beneficial effect of type I IFNs in E. coli-infected Mkp-1-/- mice is, at least in part, mediated by Janus kinase/signal transducer and activator of transcription-driven PD-L1 induction. Our studies also support the notion that enhanced PD-L1 expression contributes to the bactericidal defect of Mkp-1-/- mice.


Assuntos
Antígeno B7-H1 , Fosfatase 1 de Especificidade Dupla , Infecções por Escherichia coli , Regulação da Expressão Gênica , Interferon Tipo I , Animais , Antígeno B7-H1/genética , Fosfatase 1 de Especificidade Dupla/metabolismo , Escherichia coli/genética , Escherichia coli/imunologia , Infecções por Escherichia coli/imunologia , Regulação da Expressão Gênica/imunologia , Interferon Tipo I/genética , Camundongos
2.
Ann Diagn Pathol ; 36: 12-20, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29966831

RESUMO

Spinal cord paralysis is relatively common after surgical repair of thoraco-abdominal aortic aneurysm (TAAA) and its etiology is unknown. The present study was designed to examine the histopathology of the disease and investigate whether miR-155 ablation would reduce spinal cord ischemic damage and delayed hindlimb paralysis induced by aortic cross-clamping (ACC) in our mouse model. The loss of locomotor function in ACC-paralyzed mice correlated with the presence of extensive gray matter damage and central cord edema, with minimal white matter histopathology. qRTPCR and Western blotting showed that the spinal cords of wild-type ACC mice that escaped paralysis showed lower miR-155 expression and higher levels of transcripts encoding Mfsd2a, which is implicated in the maintenance of blood-brain barrier integrity. In situ based testing demonstrated that increased miR-155 detection in neurons was highly correlated with the gray matter damage and the loss of one of its targets, Mfsd2a, could serve as a good biomarker of the endothelial cell damage. In vitro, we demonstrated that miR-155 targeted Mfsd2a in endothelial cells and motoneurons and increased endothelial cell permeability. Finally, miR-155 ablation slowed the progression of central cord edema, and reduced the incidence of paralysis by 40%. In sum, the surgical pathology findings clearly indicated that the epicenter of the ischemic-induced paralysis was the gray matter and that endothelial cell damage correlated to Mfsd2a loss is a good biomarker of the disease. MiR-155 targeting therefore offers new therapeutic opportunity for edema caused by traumatic spinal cord injury and diagnostic pathologists, by using immunohistochemistry, can clarify if this mechanism also is important in other ischemic diseases of the CNS, including stroke.


Assuntos
Isquemia/metabolismo , Proteínas de Membrana Transportadoras/genética , MicroRNAs/genética , Traumatismos da Medula Espinal/genética , Animais , Modelos Animais de Doenças , Imuno-Histoquímica/métodos , Isquemia/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , Doenças do Sistema Nervoso/genética , Neurônios/metabolismo , Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Simportadores , Proteínas Supressoras de Tumor/genética
3.
Biochem Biophys Res Commun ; 491(1): 72-78, 2017 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-28698135

RESUMO

Thyroid cancer has long been considered to arise in middle age and progress to more aggressive and lethal cancers after its repeated proliferation. In this research, we aimed at investigating the biological function and the underlying molecular mechanism of Melanoregulin (MREG) in thyroid cancer. It was found that the expression of MREG was significantly downregulated in thyroid cancer tissues. The downregulation of MREG expression was caused by epigenetic methylation. MREG overexpression could suppress the invasion and proliferation of thyroid cancer cells. While MREG knockdown promoted the invasion and proliferation of thyroid cancer cells. Furthermore, the phosphorylation of Akt or mTOR was decreased by MREG overexpression and increased by MREG knockdown. Moreover, Dactolisib (the inhibitor of mTOR) could abrogate silenced MREG induced thyroid cancer cell invasion and proliferation. Taken together, MREG regulates thyroid cancer cell invasion and proliferation through PI3K/Akt-mTOR signaling pathway. MREG may serve as a promising therapeutic strategy for thyroid cancer.


Assuntos
Proteínas de Transporte/metabolismo , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Proteínas Adaptadoras de Transporte Vesicular , Humanos , Invasividade Neoplásica , Transdução de Sinais , Células Tumorais Cultivadas
4.
Am J Physiol Lung Cell Mol Physiol ; 307(4): L317-25, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24951775

RESUMO

Pulmonary artery smooth muscle cell (PASMC) proliferation plays a fundamental role in the vascular remodeling seen in pulmonary hypertensive diseases associated with hypoxia. Arginase II, an enzyme regulating the first step in polyamine and proline synthesis, has been shown to play a critical role in hypoxia-induced proliferation of human PASMC (hPASMC). In addition, there is evidence that patients with pulmonary hypertension have elevated levels of arginase in the vascular wall. Resveratrol, a natural polyphenol found in red wine and grape skins, has diverse biochemical and physiological actions including antiproliferative properties. Furthermore, resveratrol has been shown to attenuate right ventricular and pulmonary artery remodeling, both pathological components of pulmonary hypertension. The present studies tested the hypothesis that resveratrol would prevent hypoxia-induced pulmonary artery smooth muscle cell proliferation by inhibiting hypoxia-induced arginase II expression. Our data indicate that hypoxia-induced hPASMC proliferation is abrogated following treatment with resveratrol. In addition, the hypoxic induction of arginase II was directly attenuated by resveratrol treatment. Furthermore, we found that the inhibitory effect of resveratrol on arginase II in hPASMC was mediated through the PI3K-Akt signaling pathway. Supporting these in vitro findings, resveratrol normalized right ventricular hypertrophy in an in vivo neonatal rat model of chronic hypoxia-induced pulmonary hypertension. These novel data support the notion that resveratrol may be a potential therapeutic agent in pulmonary hypertension by preventing PASMC arginase II induction and proliferation.


Assuntos
Arginase/biossíntese , Proliferação de Células/efeitos dos fármacos , Hipóxia/fisiopatologia , Miócitos de Músculo Liso/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Estilbenos/farmacologia , Animais , Arginase/antagonistas & inibidores , Células Cultivadas , Humanos , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/tratamento farmacológico , Hipertrofia Ventricular Direita/etiologia , Hipóxia/complicações , Miócitos de Músculo Liso/metabolismo , Ratos , Resveratrol
5.
J Immunol ; 188(5): 2316-27, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22279102

RESUMO

Glutathione reductase (Gsr) catalyzes the reduction of glutathione disulfide to glutathione, which plays an important role in the bactericidal function of phagocytes. Because Gsr has been implicated in the oxidative burst in human neutrophils and is abundantly expressed in the lymphoid system, we hypothesized that Gsr-deficient mice would exhibit marked defects during the immune response against bacterial challenge. We report in this study that Gsr-null mice exhibited enhanced susceptibility to Escherichia coli challenge, indicated by dramatically increased bacterial burden, cytokine storm, striking histological abnormalities, and substantially elevated mortality. Additionally, Gsr-null mice exhibited elevated sensitivity to Staphylococcus aureus. Examination of the bactericidal functions of the neutrophils from Gsr-deficient mice in vitro revealed impaired phagocytosis and defective bacterial killing activities. Although Gsr catalyzes the regeneration of glutathione, a major cellular antioxidant, Gsr-deficient neutrophils paradoxically produced far less reactive oxygen species upon activation both ex vivo and in vivo. Unlike wild-type neutrophils that exhibited a sustained oxidative burst upon stimulation with phorbol ester and fMLP, Gsr-deficient neutrophils displayed a very transient oxidative burst that abruptly ceased shortly after stimulation. Likewise, Gsr-deficient neutrophils also exhibited an attenuated oxidative burst upon encountering E. coli. Biochemical analysis revealed that the hexose monophosphate shunt was compromised in Gsr-deficient neutrophils. Moreover, Gsr-deficient neutrophils displayed a marked impairment in the formation of neutrophil extracellular traps, a bactericidal mechanism that operates after neutrophil death. Thus, Gsr-mediated redox regulation is crucial for bacterial clearance during host defense against massive bacterial challenge.


Assuntos
Infecções por Escherichia coli/prevenção & controle , Espaço Extracelular/imunologia , Glutationa Redutase/fisiologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Estresse Oxidativo/imunologia , Fagocitose/imunologia , Infecções Estafilocócicas/prevenção & controle , Animais , Escherichia coli/imunologia , Infecções por Escherichia coli/enzimologia , Infecções por Escherichia coli/imunologia , Espaço Extracelular/genética , Espaço Extracelular/metabolismo , Glutationa Redutase/deficiência , Glutationa Redutase/genética , Humanos , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Neutrófilos/microbiologia , Estresse Oxidativo/genética , Fagocitose/genética , Infecções Estafilocócicas/enzimologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia
6.
J Minim Invasive Gynecol ; 20(2): 241-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23465260

RESUMO

Herein is described the case of a 28-year-old woman in whom uterine artery embolization (UAE) was performed to treat intramural ectopic pregnancy. The intramural ectopic pregnancy was diagnosed at magnetic resonance imaging, which showed a gestational sac surrounded completely by myometrium. The UAE procedure was uncomplicated, with satisfactory results. Intramural ectopic pregnancy may be treated using UAE, which aids in maintaining fertility.


Assuntos
Gravidez Ectópica/terapia , Embolização da Artéria Uterina , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Gravidez , Gravidez Ectópica/diagnóstico
7.
Endokrynol Pol ; 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37577996

RESUMO

INTRODUCTION: The objective was to observe the expression of miR-23a-3p in the serum of patients with type 2 diabetic nephropathy (T2DN) and to explore its clinical significance. MATERIALS AND METHODS: 112 patients with type 2 diabetes were divided into a simple diabetes mellitus (NON) group, T2DN microalbuminuria (MIC) group, and T2DN macroalbuminuria (MAC) group, according to the urinary protein-creatinine ratio (uACR). Clinical data were collected, miR-23a-3p levels in serum were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR), and clinical parameters were measured by an automatic biochemical analyser; the influencing factors of diabetic kidney disease (DKD) and the correlation between miR-23a-3p expression and clinical parameters were analysed. RESULTS: The expression of miR-23a-3p in the serum of the DKD group was lower than that of the normal control (CON) and NON groups. Correlation analysis showed that miR-23a-3p was positively correlated with urinary albumin (Albu), glycosylated haemoglobin (HbA1c), total cholesterol (CHOL), glycated albumin (GA-L), serum creatinine (Scr), fasting blood glucose (GLU), and uric acid (UA), negatively correlated with uACR and high-density lipoprotein cholesterol (HDL-C), but not correlated with urinary creatinine (CREA). The area under the receiver operating characteristic (ROC) curve (AUC) of miR-23a-3p for the diagnosis of DKD was 0.686 [95% confidence interval (CI): 0.599-0.773], with a sensitivity of 64.5% and a specificity of 71.2%; the AUC for differentiating NON from DKD was 0.700 (95% CI: 0.598-0.802), with a sensitivity of 61.8% and a specificity of 77.8%. Multivariate logistic regression analysis showed that serum miR-23a-3p levels were not associated with the development of DKD after adjusting for other levels of influence and were not significant for the differentiation of NON and DKD. CONCLUSION: Serum miR-23a-3p levels are decreased in T2DN patients, and this change becomes more significant with the severity of the disease, which may be a marker for the early diagnosis and progression of T2DN.

8.
Sci Rep ; 13(1): 12424, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528172

RESUMO

GBM (Glioblastoma) is the most lethal CNS (Central nervous system) tumor in adults, which inevitably develops resistance to standard treatments leading to recurrence and mortality. TRIB1 is a serine/threonine pseudokinase which functions as a scaffold platform that initiates degradation of its substrates like C/EBPα through the ubiquitin proteasome system and also activates MEK and Akt signaling. We found that increased TRIB1 gene expression associated with worse overall survival of GBM patients across multiple cohorts. Importantly, overexpression of TRIB1 decreased RT/TMZ (radiation therapy/temozolomide)-induced apoptosis in patient derived GBM cell lines in vitro. TRIB1 directly bound to MEK and Akt and increased ERK and Akt phosphorylation/activation. We also found that TRIB1 protein expression was maximal during G2/M transition of cell cycle in GBM cells. Furthermore, TRIB1 bound directly to HDAC1 and p53. Importantly, mice bearing TRIB1 overexpressing tumors had worse overall survival. Collectively, these data suggest that TRIB1 induces resistance of GBM cells to RT/TMZ treatments by activating the cell proliferation and survival pathways thus providing an opportunity for developing new targeted therapeutics.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Temozolomida/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Apoptose/genética , Quinases de Proteína Quinase Ativadas por Mitógeno , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia
9.
Am J Respir Cell Mol Biol ; 47(2): 218-26, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22447968

RESUMO

Arginase II has been shown to be involved in the hypoxia-induced proliferation of human pulmonary artery smooth muscle cells (hPASMCs). The signal transduction pathways responsible for the induction of arginase II are poorly understood. Cyclic AMP is involved in many intracellular processes, and cAMP levels are regulated by a balance between production via adenylate cyclases and degradation via phosphodiesterases. The purpose of this study was to determine the effects of cAMP on hypoxia-induced arginase expression, activity, and proliferation in hPASMCs. We found that the cAMP analog 8-Bromo-cAMP (8-Br-cAMP), the adenylate cyclase activator forskolin, and the phosphodiesterase 3 inhibitor cilostamide prevented the hypoxic induction of arginase II mRNA and protein expression in hPASMCs. The inhibition of arginase II protein was found to be mediated by exchange protein directly activated by cAMP. Arginase activity was decreased by 8-Br-cAMP, as evidenced by significantly lower V(max) for arginase in normoxia and hypoxia. The hypoxia-induced hPASMC proliferation was completely prevented by the addition of 8-Br-cAMP, forskolin, or cilostamide. These data are the first to describe the inhibitory effect of cAMP on arginase activity, expression, and resultant proliferation of hypoxic hPASMCs.


Assuntos
Arginase/biossíntese , AMP Cíclico/biossíntese , Miócitos de Músculo Liso/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Arginase/antagonistas & inibidores , Arginase/genética , Arginase/metabolismo , Hipóxia Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/genética , AMP Cíclico/metabolismo , Indução Enzimática/efeitos dos fármacos , Humanos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Inibidores da Fosfodiesterase 3/farmacologia , Artéria Pulmonar/metabolismo , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos
10.
J Exp Med ; 203(1): 131-40, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16380513

RESUMO

Septic shock is a leading cause of morbidity and mortality. However, genetic factors predisposing to septic shock are not fully understood. Excessive production of proinflammatory cytokines, particularly tumor necrosis factor (TNF)-alpha, and the resultant severe hypotension play a central role in the pathophysiological process. Mitogen-activated protein (MAP) kinase cascades are crucial in the biosynthesis of proinflammatory cytokines. MAP kinase phosphatase (MKP)-1 is an archetypal member of the dual specificity protein phosphatase family that dephosphorylates MAP kinase. Thus, we hypothesize that knockout of the Mkp-1 gene results in prolonged MAP kinase activation, augmented cytokine production, and increased susceptibility to endotoxic shock. Here, we show that knockout of Mkp-1 substantially sensitizes mice to endotoxic shock induced by lipopolysaccharide (LPS) challenge. We demonstrate that upon LPS challenge, Mkp-1-/- cells exhibit prolonged p38 and c-Jun NH2-terminal kinase activation as well as enhanced TNF-alpha and interleukin (IL)-6 production compared with wild-type cells. After LPS challenge, Mkp-1 knockout mice produce dramatically more TNF-alpha, IL-6, and IL-10 than do wild-type mice. Consequently, Mkp-1 knockout mice develop severe hypotension and multiple organ failure, and exhibit a remarkable increase in mortality. Our studies demonstrate that MKP-1 is a pivotal feedback control regulator of the innate immune responses and plays a critical role in suppressing endotoxin shock.


Assuntos
Proteínas de Ciclo Celular/imunologia , Proteínas Imediatamente Precoces/imunologia , Fosfoproteínas Fosfatases/imunologia , Proteínas Tirosina Fosfatases/imunologia , Choque Séptico/prevenção & controle , Animais , Proteínas de Ciclo Celular/genética , Células Cultivadas , Citocinas/imunologia , Células Dendríticas/imunologia , Fosfatase 1 de Especificidade Dupla , Proteínas Imediatamente Precoces/deficiência , Proteínas Imediatamente Precoces/genética , Imunidade Inata , Lipopolissacarídeos , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/imunologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfoproteínas Fosfatases/deficiência , Fosfoproteínas Fosfatases/genética , Proteína Fosfatase 1 , Proteínas Tirosina Fosfatases/deficiência , Proteínas Tirosina Fosfatases/genética , Choque Séptico/mortalidade , Baço/citologia , Baço/imunologia
11.
Toxicol Pathol ; 40(8): 1095-105, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22623522

RESUMO

c-Jun N-terminal kinase (JNK) activation promotes hepatocyte death during acetaminophen overdose, a common cause of drug-induced liver failure. While mitogen-activated protein kinase (MAPK) phosphatase (Mkp)-1 is a critical negative regulator of JNK MAPK, little is known about the role of Mkp-1 during hepatotoxicity. In this study, we evaluated the role of Mkp-1 during acute acetaminophen toxicity. Mkp-1⁺/⁺ and Mkp-1⁻/⁻ mice were dosed ip with vehicle or acetaminophen at 300 mg/kg (for mechanistic studies) or 400 mg/kg (for survival studies). Tissues were collected 1-6 hr post 300 mg/kg dosing to assess glutathione levels, organ damage, and MAPK activation. Mkp-1⁻/⁻ mice exhibited more rapid plasma clearance of acetaminophen than did Mkp-1⁺/⁺ mice, indicated by a quicker decline of plasma acetaminophen level. Moreover, Mkp-1⁻/⁻ mice suffered more severe liver injury, indicated by higher plasma alanine transaminase activity and more extensive centrilobular apoptosis and necrosis. Hepatic JNK activity in Mkp-1⁻/⁻ mice was higher than in Mkp-1⁺/⁺ mice. Finally, Mkp-1⁻/⁻ mice displayed a lower overall survival rate and shorter median survival time after dosing with 400 mg/kg acetaminophen. The more severe phenotype exhibited by Mkp-1⁻/⁻ mice indicates that Mkp-1 plays a protective role during acute acetaminophen overdose, potentially through regulation of JNK.


Assuntos
Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fosfatase 1 de Especificidade Dupla/metabolismo , Acetaminofen/farmacocinética , Alanina Transaminase/sangue , Analgésicos não Narcóticos/farmacocinética , Animais , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/genética , Modelos Animais de Doenças , Fosfatase 1 de Especificidade Dupla/deficiência , Fosfatase 1 de Especificidade Dupla/genética , Regulação Enzimológica da Expressão Gênica , Glutationa/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Longevidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Necrose/induzido quimicamente , Necrose/patologia
12.
J Immunol ; 183(11): 7411-9, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19890037

RESUMO

MAPKs are crucial for TNF-alpha and IL-6 production by innate immune cells in response to TLR ligands. MAPK phosphatase 1 (Mkp-1) deactivates p38 and JNK, abrogating the inflammatory response. We have previously demonstrated that Mkp-1(-/-) mice exhibit exacerbated inflammatory cytokine production and increased mortality in response to challenge with LPS and heat-killed Staphylococcus aureus. However, the function of Mkp-1 in host defense during live Gram-negative bacterial infection remains unclear. We challenged Mkp-1(+/+) and Mkp-1(-/-) mice with live Escherichia coli i.v. to examine the effects of Mkp-1 deficiency on animal survival, bacterial clearance, metabolic activity, and cytokine production. We found that Mkp-1 deficiency predisposed animals to accelerated mortality and was associated with more robust production of TNF-alpha, IL-6 and IL-10, greater bacterial burden, altered cyclooxygenase-2 and iNOS expression, and substantial changes in the mobilization of energy stores. Likewise, knockout of Mkp-1 also sensitized mice to sepsis caused by cecal ligation and puncture. IL-10 inhibition by neutralizing Ab or genetic deletion alleviated increased bacterial burden. Treatment with the bactericidal antibiotic gentamicin, given 3 h after Escherichia coli infection, protected Mkp-1(+/+) mice from septic shock but had no effect on Mkp-1(-/-) mice. Thus, during Gram-negative bacterial sepsis Mkp-1 not only plays a critical role in the regulation of cytokine production but also orchestrates the bactericidal activities of the innate immune system and controls the metabolic response to stress.


Assuntos
Fosfatase 1 de Especificidade Dupla/imunologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Inflamação/imunologia , Sepse/imunologia , Animais , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/imunologia , Fosfatase 1 de Especificidade Dupla/deficiência , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Glucose/metabolismo , Glicogênio/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/metabolismo , Hiperlipidemias/metabolismo , Hiperlipidemias/microbiologia , Inflamação/metabolismo , Inflamação/microbiologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Interleucina-6/biossíntese , Interleucina-6/imunologia , Metabolismo dos Lipídeos/imunologia , Camundongos , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/imunologia , Sepse/microbiologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologia
14.
J Biol Chem ; 284(40): 27123-34, 2009 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-19651781

RESUMO

Inducible nitric-oxide (NO) synthase (iNOS) plays a critical role in the eradication of intracellular pathogens. However, the excessive production of NO by iNOS has also been implicated in the pathogenesis of septic shock syndrome. Previously, we have demonstrated that mice deficient in mitogen-activated protein kinase phosphatase-1 (MKP-1) exhibit exaggerated inflammatory responses and rapidly succumb to lipopolysaccharide (LPS). In response to LPS, MKP-1(-/-) mice produce greater amounts of inflammatory cytokines and NO than do wild-type mice, and the MKP-1(-/-) mice exhibit severe hypotension. To understand the molecular basis for the increase in NO production, we studied the role of MKP-1 in the regulation of iNOS expression. We found that LPS challenge elicited a stronger iNOS induction in MKP-1 knock-out mice than in wild-type mice. Likewise, LPS treatment also resulted in greater iNOS expression in macrophages from MKP-1(-/-) mice than in macrophages from wild-type mice. Both accelerated gene transcription and enhanced mRNA stability contribute to the increases in iNOS expression in LPS-stimulated MKP-1(-/-) macrophages. We found that STAT-1, a transcription factor known to mediate iNOS induction by interferon-gamma, was more potently activated by LPS in MKP-1(-/-) macrophages than in wild-type cells. MicroRNA array analysis indicated that microRNA (miR)-155 expression was increased in MKP-1-deficient macrophages compared with wild-type macrophages. Transfection of miR-155 attenuated the expression of Suppressor of Cytokine Signal (SOCS)-1 and enhanced the expression of iNOS. Our results suggest that MKP-1 may negatively regulate iNOS expression by controlling the expression of miR-155 and consequently the STAT pathway via SOCS-1.


Assuntos
Fosfatase 1 de Especificidade Dupla/metabolismo , Regulação Enzimológica da Expressão Gênica , Óxido Nítrico Sintase Tipo II/genética , Animais , Linhagem Celular , Fosfatase 1 de Especificidade Dupla/deficiência , Fosfatase 1 de Especificidade Dupla/genética , Técnicas de Inativação de Genes , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação/efeitos dos fármacos , Processamento Pós-Transcricional do RNA , Estabilidade de RNA , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Fatores de Transcrição STAT/metabolismo , Ativação Transcricional , Tirosina/metabolismo
15.
Physiol Rep ; 8(17): e14559, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32914566

RESUMO

Phosphodiesterase 3 (PDE3), of which there are two isoforms, PDE3A and PDE3B, hydrolyzes cAMP and cGMP-cyclic nucleotides important in the regulation of pulmonary vascular tone. PDE3 has been implicated in pulmonary hypertension unresponsive to nitric oxide (NO); however, contributions of the two isoforms are not known. Furthermore, adenosine monophosphate-activated protein kinase (AMPK), a critical regulator of cellular energy homeostasis, has been shown to be modulated by PDE3 in varying cell types. While AMPK has recently been implicated in pulmonary hypertension pathogenesis, its role and regulation in the pulmonary vasculature remain to be elucidated. Therefore, we utilized human pulmonary artery smooth muscle cells (hPASMC) to test the hypothesis that NO increases PDE3 expression in an isoform-specific manner, thereby activating AMPK and inhibiting hPASMC proliferation. We found that in hPASMC, NO treatment increased PDE3A protein expression and PDE3 activity with a concomitant decrease in cAMP concentrations and increase in AMPK phosphorylation. Knockdown of PDE3A using siRNA transfection blunted the NO-induced AMPK activation, indicating that PDE3A plays an important role in AMPK regulation in hPASMC. Treatment with a soluble guanylate cyclase (sGC) stimulator increased PDE3A expression and AMPK activation similar to that seen with NO treatment, whereas treatment with a sGC inhibitor blunted the NO-induced increase in PDE3A and AMPK activation. These results suggest that NO increases PDE3A expression, decreases cAMP, and activates AMPK via the sGC-cGMP pathway. We speculate that NO-induced increases in PDE3A and AMPK may have implications in the pathogenesis and the response to therapies in pulmonary hypertensive disorders.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Miócitos de Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Proteínas Quinases/metabolismo , Artéria Pulmonar/citologia , Quinases Proteína-Quinases Ativadas por AMP , Células Cultivadas , AMP Cíclico/metabolismo , Humanos , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Óxido Nítrico/farmacologia
16.
Life Sci ; 83(19-20): 671-80, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18845168

RESUMO

AIMS: We have previously shown that glucocorticoids induce the expression of MAP kinase phosphatase (Mkp)(a)-1 in innate immune cells. Since Mkp-1 is a critical negative regulator of the innate immune response, we hypothesize that Mkp-1 plays a significant role in the anti-inflammatory action of glucocorticoids. The specific aim of the present study is to understand the role of Mkp-1 in the anti-inflammatory function of glucocorticoids. MAIN METHODS: Wild-type and Mkp-1(-/-) mice were treated with different doses of dexamethasone and then challenged with different doses of lipopolysaccharide (LPS). The survival and blood cytokines were assessed. The effects of dexamethasone on cytokine production in wild-type and Mkp-1(-/-) primary macrophages ex vivo were also examined. KEY FINDINGS: We found that dexamethasone induced the expression of Mkp-1 in vivo. Dexamethasone treatment completely protected wild-type mice from the mortality caused by a relatively high dose of LPS. However, dexamethasone treatment offered only a partial protection to Mkp-1(-/-) mice. Dexamethasone attenuated TNF-alpha production in both wild-type and Mkp-1(-/-) mice challenged with LPS, although TNF-alpha production in Mkp-1(-/-) mice was significantly more robust than that in wild-type mice. Dexamethasone pretreatment shortened the duration of p38 and JNK activation in LPS-stimulated wild-type macrophages, but had little effect on p38 or JNK activation in similarly treated Mkp-1(-/-) macrophages. SIGNIFICANCE: Our results indicate that the inhibition of p38 and JNK activities by glucocorticoids is mediated by enhanced Mkp-1 expression. These results demonstrate that dexamethasone exerts its anti-inflammatory effects through both Mkp-1-dependent and Mkp-1-indepent mechanisms.


Assuntos
Anti-Inflamatórios/farmacologia , Dexametasona/farmacologia , Fosfatase 1 de Especificidade Dupla/fisiologia , Endotoxemia/enzimologia , Endotoxemia/prevenção & controle , Animais , Northern Blotting , Western Blotting , Citocinas/biossíntese , Fosfatase 1 de Especificidade Dupla/genética , Ativação Enzimática/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Lipopolissacarídeos/toxicidade , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/enzimologia , Camundongos , Camundongos Knockout , Baço/citologia , Baço/efeitos dos fármacos , Baço/enzimologia
17.
Sci Rep ; 8(1): 5103, 2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29572456

RESUMO

This retrospective consecutive case series aimed to evaluate spectral-domain optical coherence tomography (SD-OCT) for occult macular disease recognition preoperatively in patients scheduled for routine cataract surgery. All patients scheduled for cataract surgery underwent macular SD-OCT. Scans were reviewed for retinal, retinal pigment epithelium and vitreomacular interface abnormalities. For the subgroup analysis, the following information was collected: age; sex; and diabetes, hypertension, myopia, glaucoma, post intra-ocular surgery, endophotocoagulation, retinal vasculopathy and uveitis statuses. One-thousand-one-hundred-seventy-six consecutive scans were acquired from 1,176 patients. Macular pathology was found in 294 eyes. The most common macular disorders were an epiretinal membrane (n = 130), myopia atrophy (n = 61) and a dome-shaped macular with pathologic myopia (n = 32). One-hundred-thirty eyes (11.05%) presented macular epiretinal membranes not detected by dilated fundus examination, accounting for 44.22% of the abnormalities in diseased eyes and was higher than in previous Chinese studies. Some had multiple macular disorders. The most common ocular history was myopia, including high myopia. The pooled prevalence rate of macular diseases detected by OCT was 0.24 (95% CI 0.14-0.34) using meta-analysis. SD-OCT should be performed for routine cataract surgery patients to evaluate visual outcomes, especially in myopic patients and those considering advanced-technology intraocular lenses.


Assuntos
Extração de Catarata , Macula Lutea/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Catarata/epidemiologia , Extração de Catarata/métodos , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/epidemiologia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos
18.
Zhonghua Nei Ke Za Zhi ; 46(4): 284-6, 2007 Apr.
Artigo em Zh | MEDLINE | ID: mdl-17637264

RESUMO

OBJECTIVE: To investigate the clinical manifestations, treatment and prognosis of antiphospholipid syndrome (APS). METHODS: The cases of 72 patients with defined APS admitted from Jan 1990 to Jan 2006 were analyzed retrospectively. RESULTS: 21 patients with primary APS and 51 patients with secondary APS were studied. Vascular thrombosis was present in 43 (59.7%) of the 72 patients in this study. Cardiac abnormalities could be observed in 48 patients (66.6%). Lesions most frequently involved left-sided valves, mitral (35.4%) more commonly affected than aortic (16.7%). Cardiac involvement was significantly related to thrombosis (P = 0.007) and prolonged activated partial thromboplastin time (APTT) (P = 0.026). Valvular involvement was significantly related to brain infarcts (P = 0.008) and thrombosis (P = 0.029). 20 APS patients with cardiac abnormalities and thrombosis received anticoagulation therapy and thrombosis did not happen any more during follow-up. CONCLUSION: Cardiac manifestations of APS are valve abnormalities (valve thickening and vegetations), occlusive arterial disease (atherosclerosis and myocardial infarction), ventricular dysfunction and pulmonary hypertension. Cardiac abnormalities in APS are likely to be related to hypercoagulability.


Assuntos
Síndrome Antifosfolipídica/complicações , Doenças das Valvas Cardíacas/etiologia , Tromboembolia/etiologia , Adulto , Idoso , Anticorpos Anticardiolipina/análise , Síndrome Antifosfolipídica/imunologia , Feminino , Seguimentos , Humanos , Inibidor de Coagulação do Lúpus/análise , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Int J Oncol ; 50(4): 1330-1340, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259944

RESUMO

Cervical cancer is a cause of cancer death, making it one of the most common causes of death among women globally. Previously, a variety of studies have revealed the molecular mechanisms by which cervical cancer develops. However, there are still limitations in treatment for cervical cancer. Ursolic acid is a naturally derived pentacyclic triterpene acid, exhibiting broad anticancer effects. Nanoparticulate drug delivery systems have been known to better the bioavailability of drugs on intranasal administration compared with only drug solutions. Administration of ursolic acid nanoparticles is thought to be sufficient to lead to considerable suppression of cervical cancer progression. We loaded gold-ursolic acid into poly(DL-lactide-co-glycolide) nanoparticles to cervical cancer cell lines due to the properties of ursolic acid in altering cellular processes and the easier absorbance of nanoparticles. In addition, in this study, ursolic acid nanoparticles were administered to cervical cancer cells to find effective treatments for cervical cancer inhibition. In the present study, ELISA, western blotting, flow cytometry and immunohistochemistry assays were carried out to calculate the molecular mechanism by which ursolic acid nanoparticles modulated cervical cancer progression. Data indicated that ursolic acid nanoparticles, indeed, significantly suppress cervial cancer cell proliferation, invasion and migration compared to the control group, and apoptosis was induced by ursolic acid nanoparticles in cervical cancer cells through activating caspases, p53 and suppressing anti-apoptosis-related signals. Furthermore, tumor size was reduced by treatment of ursolic acid nanoparticles in in vivo experiments. In conclusion, this study suggests that ursolic acid nanoparticles inhibited cervical cancer cell proliferation via apoptosis induction, which could be a potential target for future therapeutic strategy clinically.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Triterpenos/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Materiais Biocompatíveis/química , Caspases/metabolismo , Portadores de Fármacos/química , Feminino , Ouro/química , Células HeLa , Humanos , Injeções Intraperitoneais , Masculino , Camundongos Nus , Nanopartículas/química , Poliglactina 910/química , Triterpenos/administração & dosagem , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Ácido Ursólico
20.
Sci Rep ; 7(1): 8936, 2017 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-28827524

RESUMO

The purpose of the present study was to investigate the vascular flow density (VD) of macular superficial (SCP), deep capillary plexus (DCP), and choriocapillaris and the size of the foveal avascular zone (FAZ) area in healthy children using optical coherence tomography angiography (OCTA). The potential associations of age, sex, intraocular pressure, body mass index, spherical equivalent, and axial length with OCTA parameters were also investigated. A total of 75 eyes from 75 healthy children were included for analysis, with the mean age 11.51 ± 1.91 years (range, 8-16 years). At the level of the SCP, mean VD and mean FAZ area were, respectively, 54.29 ± 2.25% and 0.290 ± 0.109 mm2. At the level of the DCP and choriocapillaris, mean VD were 60.19 ± 1.76% and 66.58 ± 1.33%, respectively. After adjustment on the signal strength index, there was no significant correlation between age and all OCTA parameters. Intra-observer repeatability was 0.91, 0.82, and 0.88 in the SCP, DCP and choriocapillaris, respectively. In healthy eyes of children, only sex has a significant influence on the FAZ area. OCTA may provide a noninvasive and reliable approach for evaluating macular perfusion in children, although sex-related variations should be considered.


Assuntos
Macula Lutea/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adolescente , Criança , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Variações Dependentes do Observador , Imagem Óptica/métodos , Reprodutibilidade dos Testes , Fatores Sexuais
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