Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Endocr J ; 71(7): 713-719, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38658359

RESUMO

Cardiovascular disease is one of the most important complications in girls and women with Turner syndrome (TS). Although the latest international guideline provides useful suggestions for the management of cardiovascular diseases in TS, some unknown cardiac conditions warrant physicians' attention and awareness. Here, we have reported two adult cases wherein significant cardiovascular diseases were detected during the transition period. The first case patient was diagnosed with aortic crank deformity and left subclavian artery aneurysm at 14 years based on the report of cardiac catheterization, computed tomography angiography, and cardiac magnetic resonance imaging, which had remained undetected by annual evaluations using transthoracic echocardiography (TTE). This case emphasizes the importance of cardiac reevaluation during the transition period. The second case patient was diagnosed with moderate mitral valve regurgitation (MR) due to mitral valve prolapse at 18 years through TTE, although the first evaluation at 7 years by TTE detected slight MR without any clinical concerns. The condition however progressed to severe MR at 28 years, requiring mitral valvuloplasty. MR is the most common valve disease worldwide, which makes it challenging to comprehend whether the condition is a complication. However, the condition requiring surgery at this age is extremely rare, which implies the possibility of early progression. Because almost all literature on cardiovascular complications in TS is cross-sectional, further information about longitudinal cardiovascular conditions is vital for optimal care for girls and women with TS. The two cases reported in this article provide significant information for improving lifelong cardiovascular health issues in TS.


Assuntos
Síndrome de Turner , Humanos , Síndrome de Turner/complicações , Síndrome de Turner/terapia , Feminino , Adulto , Adolescente , Ecocardiografia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/terapia , Doenças Cardiovasculares/etiologia
2.
Nephrol Dial Transplant ; 27(9): 3456-64, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22187316

RESUMO

BACKGROUND: 11ß-Hydroxysteroid dehydrogenase Type 1 (11ßHSD-1) amplifies intracellular levels of active glucocorticoids which possess protective effects against organ ischaemia and reperfusion (I/R). However, the mechanisms by which 11ßHSD-1 is modified after a renal I/R challenge remain unclear. This study investigated the effect of ß(2)-adrenoceptor (ß(2)-AR) activation and the subsequent signalling pathways on renal 11ßHSD-1 gene expression following renal I/R. METHODS: Renal I/R was induced using 25 min of bilateral renal artery occlusion in 4-week-old Wistar rats followed by an intraperitoneal injection of various doses of adeno-ß(2)-AR gene. Following renal I/R, kidneys, plasma and urine were collected to assay 11ßHSD messenger RNA (mRNA) levels, ß(2)-AR signalling cascades and renal function. RESULTS: On the second day after the renal I/R challenge, there was a reduction in renal 11ßHSD-1 mRNA levels associated with a decrease in stimulatory G protein α (Gsα) and adenylate cyclase-1 (ACY-1) in the kidney. The addition of the adeno-ß(2)-AR gene resulted in greater increases in 11ßHSD-1 mRNA and ß(2)-AR-Gsα-ACY-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) activity in the kidney but had no effect on 11ßHSD-2 mRNA or protein kinase C levels in the kidney. CONCLUSIONS: Over-expression of ß(2)-AR resulting from the gene delivery improved renal function and 11ßHSD-1 production following renal I/R, which were actions exerted through the cAMP-PKA pathway. The stimulatory effect of functional ß(2)-AR activation on renal 11ßHSD-1 expression may offer a means of protection from renal I/R injury.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Rim/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Animais , Western Blotting , AMP Cíclico/genética , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Rim/citologia , Masculino , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Receptores Adrenérgicos beta 2/genética , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/prevenção & controle , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
J Nephrol ; 23(3): 341-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20349426

RESUMO

BACKGROUND: Renal infections elevate the risk of sepsis and are important causes of septic shock and multiple organ failure. The objective of the present study was to test the hypothesis that renal beta(2)-adrenoceptor (beta(2)-AR) blockade impairs the organ response to renal infection induced by Escherichia coli (E. coli) administration. METHODS: A rat model of renal infection was induced using an intraparenchymal injection of E. coli into the right kidney, either alone or in rats pre-treated with the beta(2)-AR antagonist, ICI 118,551 (3.14 microg/kg). RESULTS: The rat renal infection model significantly raised growth-related oncogene/keratinocyte-derived cytokine, granulocyte-macrophage colony-stimulating factor and cAMP levels in the right kidney and caused an elevation in serum cytokines and nitric oxide (NO), whereas creatinine clearance rate (Ccr) was maintained over the course of the infection. Conversely, treatment of the rat model with the beta(2)-AR antagonist resulted in a decrease of Ccr and serum NO, greater increases in serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6, associated with an elevation of the right renal TNF-alpha and cannabinoid-1 receptor, and a reduction of the right renal Gsalpha and cAMP levels. Moreover, the inhibition of beta(2)-AR activation impaired the clearance of endotoxins from the kidney and was associated with a raised mortality rate. CONCLUSIONS: The blockade of a renal beta(2)-AR signaling cascade aggravates inflammatory responses in the infected kidney, changes serum levels of cytokines, NO, and noradrenaline, and leads to renal dysfunction and a higher rate of mortality.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 2 , Infecções por Escherichia coli/imunologia , Nefropatias/imunologia , Animais , AMP Cíclico/biossíntese , Citocinas/sangue , Infecções por Escherichia coli/metabolismo , Nefropatias/metabolismo , Masculino , Óxido Nítrico/sangue , Norepinefrina/sangue , Ratos , Ratos Wistar , Transdução de Sinais
4.
Nephrol Dial Transplant ; 25(3): 730-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19887504

RESUMO

BACKGROUND: Sepsis is a common cause of acute renal failure (ARF) and results in a high mortality rate. The objective of the present study was to evaluate adenoviral transgenes containing the human beta(2)-adrenoceptor (adeno-beta(2)-AR) as a possible therapy for subjects at high risk for developing sepsis-induced ARF. METHODS: An endotoxaemic rat model of ARF was induced by renal artery occlusion plus subcutaneous injections of Escherichia coli in 4-week-old Wistar rats. A subset of rats was given intraperitoneal injection of the adeno-beta(2)-AR gene. RESULTS: Sepsis produced a depression in glomerular filtration rate and in the renal beta(2)-AR signalling system, which were both reversed by delivery of the beta(2)-AR gene. While delivery of the adeno-beta(2)-AR gene had no effect on recovery of cytokines and C-reactive protein in the systemic circulation, it did significantly depress (P < 0.01) the expression of the renal cannabinoid-1 (CB-1) receptor, CD14, toll-like receptor 4 (TLR4) and tumour necrosis factor (TNF)-alpha protein. Gene delivery also increased nitric oxide (NO) and decreased angiotensin II (Ang II). Finally, transfer of the beta(2)-AR gene also improved the survival of the rats exposed to sepsis-induced ARF. CONCLUSIONS: A renal-specific over-expression of beta(2)-AR, resulting from gene delivery, appeared to modulate renal dysfunction and inflammation following sepsis by altering cAMP-PKA, CB-1 and CD14-TLR4-TNF-alpha pathways. In addition, gene delivery and activation of beta(2)-AR produced modulation of systemic NO and Ang II, which further protected against renal dysfunction. Administration of the Adeno-beta(2)-AR gene has potential as a therapeutic agent against ARF following the onset of sepsis.


Assuntos
Injúria Renal Aguda/microbiologia , Injúria Renal Aguda/prevenção & controle , Adenoviridae/genética , Terapia Genética/métodos , Receptores Adrenérgicos beta 2/genética , Sepse/complicações , Animais , Modelos Animais de Doenças , Escherichia coli/patogenicidade , Infecções por Escherichia coli/complicações , Humanos , Injeções Subcutâneas , Rim/metabolismo , Rim/microbiologia , Receptores de Lipopolissacarídeos/metabolismo , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/metabolismo , Obstrução da Artéria Renal/complicações , Transdução de Sinais/fisiologia , Receptor 1 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Inflammation ; 32(1): 12-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19020966

RESUMO

The aim of this study was to define the contribution of renal beta(2)-adrenoceptor (beta(2)-AR) system to regulation of the lipopolysaccharide (LPS) transport system in the kidney of endotoxin-induced septic rats. Seven-week-old Wistar rats (n = 6/groups) pre-treated with the beta(2)-AR antagonist (ICI118,551: 3.14 microg/kg) or saline were injected with LPS (10 mg/kg i.p.) or saline, and then 24 hours later, renal function, beta(2)-AR signaling proteins, innate immune proteins, and cytokines were assayed. The injection of LPS depressed creatinine clearance rate (Ccr) associated with the reduction of renal Gsalpha and cAMP levels by a single dose of ICI118,551. On the other hand, renal CD14, toll-like receptor 4(TLR4), and tumour necrosis factor (TNF)-alpha protein expressions were significantly increased (P < 0.05) by the combination of LPS and ICI118,551. The reduction of Ccr by LPS plus ICI118,551 suggests a possibility that renal specific up-regulation of the CD14-TLR4-TNF-alpha signaling cascade by beta(2)-AR inhibition might be involved in sepsis-induced ARF.


Assuntos
Injúria Renal Aguda/metabolismo , Rim/metabolismo , Lipopolissacarídeos/metabolismo , Receptores Adrenérgicos beta 2/fisiologia , Sepse/metabolismo , Injúria Renal Aguda/etiologia , Antagonistas Adrenérgicos beta/farmacologia , Animais , Transporte Biológico , Endotoxinas/toxicidade , Rim/efeitos dos fármacos , Propanolaminas/farmacologia , Ratos , Ratos Wistar , Sepse/complicações
6.
J Infect Chemother ; 12(6): 372-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17235643

RESUMO

We tried to verify whether the currently employed diagnosis and treatment of community-acquired pneumonia in children were appropriate. For this purpose, we created tentative criteria for the classification of pediatric community-acquired pneumonia. We classified the community-acquired pneumonia into ten categories: (1) bacterial, (2) concomitant viral-bacterial, (3) viral, (4) mycoplasmal, (5) concomitant mycoplasmal-bacterial, (6) concomitant mycoplasmal-viral, (7) chlamydial, (8) concomitant chlamydial-bacterial, (9) concomitant chlamydial-viral, and (10) unknown. Children aged 1 month to 13 years with radiographic and clinical evidence of pneumonia were enrolled. Between October 2001 and September 2002, we enrolled 165 patients. The etiologic agents were determined in 126 of the 157 (80.3%) patients who were finally diagnosed with pneumonia. Two blood cultures were positive for Haemophilus influenzae type b and Streptococcus pneumoniae. A viral infection alone was found in 28 of the 157 patients (17.8%), a bacterial (without mycoplasmal) alone infection in 42 (26.8%), a concomitant viral-bacterial infection in 28 (17.8%), and a mycoplasmal infection in 27 (17.2%) patients. RS virus was identified in 28 patients (17.8%), influenza A in 12 (7.6%), parainfluenza 3 in 8 (5.1%), adenovirus in 8 (5.1%), and influenza B and measles virus in 1 patient each. Streptococcus pneumoniae was the most common cause of bacterial pneumonia. We chose the initial treatment according to clinical and laboratory findings on admission (i.e., patients' age, clinical course, chest X-ray, and laboratory findings). In 68 of the 71 patients with bacterial (without mycoplasmal) pneumonia, an appropriate antibacterial-agent was prescribed. In 25 of the 27 patients with mycoplasmal pneumonia, clindamycin and minocycline were prescribed.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , Proteína C-Reativa/análise , Pneumonia/microbiologia , Pneumonia/virologia , Criança , Pré-Escolar , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/virologia , Feminino , Humanos , Lactente , Japão/epidemiologia , Masculino , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/epidemiologia , Admissão do Paciente , Pneumonia/tratamento farmacológico , Pneumonia/epidemiologia , Padrões de Prática Médica/estatística & dados numéricos , Estudos Retrospectivos , Testes Sorológicos/métodos
7.
Clin Sci (Lond) ; 109(6): 503-11, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16076286

RESUMO

Successful gene therapy requires gene delivery that is efficient, has an optimal route of administration and has biosafety. The aims of the present study were to evaluate the safety and applicability of the subcutaneous delivery route for adenoviral transgenes containing the human beta(2)-adrenoceptor (adeno-beta(2)-AR) and to investigate whether this approach prevented renal dysfunction in a rat model of endotoxaemic shock induced by LPS (lipopolysaccharide). Subcutaneous administration of adeno-beta(2)-AR (a total of 10(10) viral particles) significantly increased beta-AR density in the kidney, lung and liver, but was without effect on physiological and plasma biochemical parameters. Moreover, this dose of virus did not cause any of the potential toxic responses of viral administration, such as inflammation and tissue TNF (tumour necrosis factor)-alpha expression. Although the LPS challenge caused a decrease in glomerular filtration rate, fractional excretion of sodium and renal beta-AR density in all groups, the reduction in renal function was significantly less in the rats given adeno-beta(2)-AR compared with non-treated rats. Thus, although further evaluation will be required, this initial study demonstrated that the subcutaneous injection of adeno-beta(2)-AR was efficient, comparatively non-pathogenic and potentially therapeutic to deal with acute renal failure associated with sepsis.


Assuntos
Injúria Renal Aguda/prevenção & controle , Adenoviridae/genética , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Receptores Adrenérgicos beta 2/genética , Sepse/terapia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/virologia , Animais , Northern Blotting/métodos , Fibrose , Engenharia Genética , Injeções Subcutâneas , Rim/imunologia , Rim/metabolismo , Rim/virologia , Lipopolissacarídeos , Modelos Animais , RNA Mensageiro/análise , Ratos , Ratos Wistar , Segurança , Sepse/imunologia , Sepse/metabolismo , Transdução Genética/métodos , Fator de Necrose Tumoral alfa/genética
9.
J Am Soc Nephrol ; 15(2): 316-25, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14747378

RESUMO

Abnormalities in the beta(2)-adrenergic control of organ function have been implicated in the pathogenesis of several disease states, such as septic shock. The objectives of the present study were to define the contribution of beta(2)-adrenoceptors (beta(2)-AR) to normal renal physiology and to investigate whether overexpression of renal beta(2)-AR might be potentially beneficial in preventing progressive renal damage associated with endotoxemia. Adenoviral transgenes containing the human beta(2)-AR (Adeno-beta(2)-AR) were constructed and delivered into the rat kidney by means of intraparenchymal injections. Administration of 10(9) total viral particles of Adeno-beta(2)-AR induced an approximately threefold increase in beta(2)-AR density in the renal tissue, which 2 wk after delivery, enhanced GFR and sodium reabsorption compared with control rats. The enhanced GFR was abolished by the addition of the beta(2)-AR antagonist, ICI 118,551. Administration of lipopolysaccharide (LPS) caused a reduction in GFR, beta(2)-AR density, and cAMP together with enhanced TNF-alpha mRNA in the kidney. In rats overexpressing beta(2)-AR, the reduction in baseline GFR and elevation of TNF-alpha mRNA and leukocyte infiltration into the kidney associated with the endotoxin were blocked. These findings suggested the possibility that a renal-specific overexpression of beta(2)-AR preserves basal renal function in response to a ligand-independent beta(2)-AR activation and that the delivery of Adeno-beta(2)-AR gene is a potential novel therapeutic strategy for treatment of acute renal failure associated with sepsis.


Assuntos
Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Receptores Adrenérgicos beta 2/fisiologia , Receptores Adrenérgicos beta 2/uso terapêutico , Sepse/complicações , Injúria Renal Aguda/fisiopatologia , Adenoviridae/genética , Animais , Endotoxinas , Taxa de Filtração Glomerular , Rim/química , Rim/fisiopatologia , Ratos , Ratos Wistar , Receptores Adrenérgicos beta 2/análise , Receptores Adrenérgicos beta 2/biossíntese , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
10.
Biochem Pharmacol ; 66(2): 343-53, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12826277

RESUMO

Apoptosis is regulated by several pathways, such as caspases, mitogen activated protein kinase (MAPK) and cAMP/cAMP-dependent protein kinase A (PKA) cascade. This study investigated the effect of beta(2)-adrenoceptor activation on Shiga toxin (Stx)2-induced apoptosis in renal tubular cells and the contribution of these signalling pathways. Cultured human adenocarcinoma-derived tubular cells were exposed to Stx2 (64 pg/mL) for 2-24hr following the addition of the beta(2)-adrenoceptor agonist (terbutaline) to the incubation medium. Stx2-induced apoptosis and its amelioration by beta(2)-adrenoceptor activation was confirmed using DNA degradation assays and by flow cytometry for annexin V, mitochondrial membrane potential and caspase(-3 and -7) activity. Exposure of cells to Stx2 for 24hr increased the DNA fragmentation to 11.6+/-0.9%, compared to 3.3+/-0.2% in control cells (P<0.05) but was decreased to approximately 5-7% (P<0.05) in the presence of terbutaline. Furthermore, Stx2-stimulated apoptosis, detected by TUNEL, annexin V and mitochondrial potential, was inhibited by terbutaline (P<0.05) which was prevented by cAMP-PKA inhibitors and a beta(2)-adrenoceptor antagonist. However, inhibition of Stx2-mediated caspase activity by terbutaline was partially blocked by cAMP-PKA inhibitors. On the other hand, p38MAPK inhibition by terbutaline prevented Stx2-induced apoptosis and caspase activity through a cAMP-independent pathway via beta(2)-adrenoceptor. These data indicate that beta(2)-adrenoceptor activation can inhibit Stx2-induced apoptosis of the cells, which may be caused by a reduction in caspase activity through cAMP-PKA activation and the p38MAPK pathway.


Assuntos
Apoptose , Células Epiteliais/efeitos dos fármacos , Túbulos Renais Coletores/citologia , Receptores Adrenérgicos beta 2/fisiologia , Toxina Shiga II/farmacologia , Anexina A5/farmacologia , Caspases/metabolismo , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico , DNA/metabolismo , Eletroforese em Gel de Ágar , Células Epiteliais/citologia , Humanos , Marcação In Situ das Extremidades Cortadas , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptores Adrenérgicos beta 2/metabolismo
11.
Brain Dev ; 24(7): 715-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12427520

RESUMO

Carrier detection for 12 women and prenatal diagnosis for six fetuses in Japanese families with a patient with Menkes disease (MNK) were performed by gene analysis and/or measurement of the copper concentration in cultured cells. Six out of eight mothers of MNK patients were carriers while two (25%) were not carriers. Two unrelated patients showed the same mutation (R986X): one patient's mother was a carrier while the other was not. One male and three female fetuses did not have the same mutant allele as the respective MNK proband and have been healthy since birth. One female fetus had the same mutant allele as her affected brother. Gene analysis is very useful and reliable, although such examination is only indicated in families in which a mutation has been identified. In one family in which a mutation in ATP7A was not found, cultured amniocytes from a male fetus had a high copper concentration. Thus after his birth, the biochemical findings confirmed the presence of MNK and early treatment was started. As his early treatment with parenteral copper-histidine prevented the neurological disorders effectively, prenatal diagnosis is very important.


Assuntos
Doenças Fetais/diagnóstico , Síndrome dos Cabelos Torcidos/diagnóstico , Diagnóstico Pré-Natal/métodos , Amniocentese , Âmnio/química , Células Cultivadas , Córion/química , Amostra da Vilosidade Coriônica , Cobre/análise , Análise Mutacional de DNA , Feminino , Doenças Fetais/genética , Fibroblastos/química , Humanos , Masculino , Síndrome dos Cabelos Torcidos/genética , Mutação , Linhagem , Reação em Cadeia da Polimerase , Gravidez
12.
Cytokine ; 19(1): 47-51, 2002 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-12200113

RESUMO

Previous findings indicated that cAMP had an inhibitory effect of on tumour necrosis factor (TNF)-alpha production. Angiotensin II (Ang II) may activate the cAMP-protein kinase A (PKA) pathway in renal mesangial cells through synthesis of prostaglandins (PGs) and the possibility arises that inhibition of Ang II-induced cAMP formation might result in the overproduction of TNF-alpha in the cell and this hypothesis was tested in the present study. Rat mesangial cells were exposed to Ang II in the presence or absence of cyclooxygenase inhibitor (indomethacin) or cAMP-PKA inhibitor (H-89). Exposure of mesangial cell to Ang II (10(-6)M-10(-8)M) significantly increased intracellular cAMP level through type 1 Ang II receptor but had no effect on TNF-alpha protein release, transcriptional activity, or mRNA. However, following the addition of indomethacin or H-89, Ang II significantly increased TNF-alpha release, transcriptional activity, and mRNA level. These data suggested that in mesangial cells after blockade of cAMP-PKA by PG inhibition, Ang II was capable of stimulating TNF-alpha transcription which subsequently increased TNF-alpha mRNA accumulation and protein release.


Assuntos
Angiotensina II/fisiologia , AMP Cíclico/metabolismo , Sulfonamidas , Fator de Necrose Tumoral alfa/biossíntese , Animais , Northern Blotting , Genes Reporter , Mesângio Glomerular/patologia , Indometacina/farmacologia , Isoquinolinas/farmacologia , Prostaglandinas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
13.
Jpn J Pharmacol ; 88(2): 139-45, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11928713

RESUMO

The present study was designed to clarify the role of angiotensin II (Ang II) in modulating renal tumor necrosis factor (TNF)-alpha and interleukin-6 (IL-6) production and to investigate the effect of one dose of Ang II inhibitor on cytokines production following lipopolysaccharide (LPS) to cause endotoxemia. Two studies were performed: 1) Ang II was infused intravenously at a rate of 0.2 microg/kg per minute for 4 h in rats and then kidneys were collected to assay TNF-alpha and IL-6 mRNA levels; 2) Four-week-old Wistar rats pre-treated with angiotensin-converting enzyme inhibitor, enalapril, or type I Ang II-receptor antagonist, TCV-116, were injected with LPS (0.1, 0.5, 1.0 mg, i.p.), and then 2 or 4 h later, kidneys were collected to assay TNF-alpha, IL-6, renin and angiotensinogen mRNA levels. After a 4-h intravenous infusion of Ang II, renal TNF-alpha or IL-6 mRNA level significantly increased 1.9-fold or 2.1-fold (each P<0.05) to the control level, respectively. LPS stimulated TNF-alpha, IL-6 and angiotensinogen mRNA levels in the kidney but in rats given enalapril or TCV-116, LPS-induced IL-6 and TNF-alpha mRNA levels were completely suppressed (each P<0.05). This suggests that a single dose of renin-angiotensin system inhibitor suppressed renal IL-6 and TNF-alpha production and may prevent cytokine-induced renal damage during endotoxemia.


Assuntos
Endotoxinas/farmacologia , Interleucina-6/genética , Rim/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Tetrazóis , Fator de Necrose Tumoral alfa/genética , Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Angiotensinogênio/genética , Animais , Benzimidazóis/farmacologia , Compostos de Bifenilo/farmacologia , Northern Blotting , Citocinas/genética , Enalapril/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-6/antagonistas & inibidores , Rim/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina , Renina/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores
14.
J Am Soc Nephrol ; 12(11): 2288-2299, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11675405

RESUMO

Exposure of renal tubular epithelial cells to shiga toxin 2 (Stx-2) causes cytotoxicity, and the potency of this toxin is enhanced in the presence of tumor necrosis factor-alpha (TNF-alpha). It has been shown that Stx-2 induces TNF-alpha production and that activation of beta(2)-adrenoceptors downregulates TNF-alpha. However, little is known about the signaling pathway by which beta(2)-adrenoceptor agonists suppress the Stx-2-induced TNF-alpha gene transcription. The possible signaling components involved in this pathway were investigated. Human adenocarcinoma-derived renal tubular epithelial cells (ACHN) were exposed to Stx-2 in the presence or absence of a beta(2)-adrenoceptor agonist. Mitogen-activated protein kinase (MAPK), activating protein-1 (AP-1), and nuclear factor-kappa B (NF-kappa B) were measured to evaluate the regulatory mechanisms involved in TNF-alpha gene transcription. Stx-2 (4 pg/ml) stimulated MAPK (p42/p44, p38) and AP-1 and increased TNF-alpha promoter activity by 2.4-fold. The increase in TNF-alpha was attenuated by both a p42/p44 inhibitor, PD098059 (10(-6) M), and a p38 inhibitor, SB203580 (10(-6) M), and AP-1-binding activity was inhibited by PD098059. Terbutaline (10(-6) M to 10(-8) M) suppressed MAPK (p42/p44, p38), NF-kappa B (p50, p65), and TNF-alpha promoter activity in a dose-dependent way that was prevented by the beta(2)-adrenoceptor antagonist, ICI118,551. However, inhibition of MAPK (p42/p44) and TNF-alpha promoter activity was partially prevented by the cAMP-protein kinase (PKA) inhibitors, H-89 (5 x 10(-6) M) and KT5720 (10(-5) M), whereas the suppression of p38 MAPK or NF-kappa B (p50) was not blocked by these inhibitors. The suppression of NF-kappa B (p65) was completely overcome by H-89 or KT5720. In summary, the downregulation of TNF-alpha transcription by terbutaline was mediated by an inhibitory effect of beta(2)-adrenoceptor activation on MAPK (p42/p44, p38) and NF-kappa B (p50/p65), which were exerted through a cAMP-PKA pathway and a cAMP-independent mechanism. It is likely that cAMP-PKA and MAPK (p42/p44, p38) may play a critical role in the regulation of the Stx-2-induced TNF-alpha transcription via beta(2)-adrenoceptor activation.


Assuntos
Receptores Adrenérgicos beta 2/fisiologia , Toxina Shiga II/antagonistas & inibidores , Toxina Shiga II/farmacologia , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/fisiologia , Fator de Necrose Tumoral alfa/genética , Agonistas Adrenérgicos beta/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/fisiologia , Fator de Transcrição AP-1/metabolismo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA