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1.
Lancet Respir Med ; 11(4): 341-353, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36372082

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a major cause of hospitalisation in infants. The burden of RSV infection in healthy term infants has not yet been established. Accurate health-care burden data in healthy infants are necessary to determine RSV immunisation policy when RSV immunisation becomes available. METHODS: We performed a multicentre, prospective, observational birth cohort study in healthy term-born infants (≥37 weeks of gestation) in five sites located in different European countries to determine the health-care burden of RSV. The incidence of RSV-associated hospitalisations in the first year of life was determined by parental questionnaires and hospital chart reviews. We performed active RSV surveillance in a nested cohort to determine the incidence of medically attended RSV infections. The study is registered with ClinicalTrials.gov, NCT03627572. FINDINGS: In total, 9154 infants born between July 1, 2017, and April 1, 2020, were followed up during the first year of life and 993 participated in the nested active surveillance cohort. The incidence of RSV-associated hospitalisations in the total cohort was 1·8% (95% CI 1·6-2·1). There were eight paediatric intensive care unit admissions, corresponding to 5·5% of 145 RSV-associated hospitalisations and 0·09% of the total cohort. Incidence of RSV infection in the active surveillance cohort confirmed by any diagnostic assay was 26·2% (24·0-28·6) and that of medically attended RSV infection was 14·1% (12·3-16·0). INTERPRETATION: RSV-associated acute respiratory infection causes substantial morbidity, leading to the hospitalisation of one in every 56 healthy term-born infants in high-income settings. Immunisation of pregnant women or healthy term-born infants during their first winter season could have a major effect on the health-care burden caused by RSV infections. FUNDING: Innovative Medicines Initiative 2 Joint Undertaking, with support from the EU's Horizon 2020 research and innovation programme and European Federation of Pharmaceutical Industries and Associations.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Criança , Feminino , Humanos , Lactente , Gravidez , Estudos de Coortes , Europa (Continente)/epidemiologia , Hospitalização , Estudos Prospectivos
2.
Hepatology ; 53(4): 1109-17, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21480317

RESUMO

UNLABELLED: Anemia may increase the likelihood of achieving a sustained virological response (SVR) during pegylated interferon and ribavirin treatment of hepatitis C virus (HCV) infection. To determine whether hemoglobin decline is associated with SVR, we retrospectively evaluated the CHARIOT study of 871 treatment-naïve HCV genotype 1 patients. Anemia (serum hemoglobin <100 g/L) occurred in 137 (16%) patients, of whom only 14 (10%) received erythropoietin. Hemoglobin decline >30g/L from baseline occurred in 76% of patients overall, including 526 patients who did not become anemic. Virological responses were higher in anemic patients compared with those who did not develop anemia (end of treatment, 80% versus 65%, P = 0.003; SVR, 61% versus 50%, P = 0.02); these differences remained significant when patients receiving erythropoietin were excluded from analysis. SVR was also higher in patients with hemoglobin decline >30 g/L compared with patients without a similar decline. In multiple logistic regression analyses with treatment group and baseline characteristics, the odds ratio for SVR was 1.97 (95% confidence interval, 1.08-3.62) for anemia and 2.17 (95% confidence interval, 1.31-3.62) for hemoglobin decline >30 g/L. Patients who first developed a hemoglobin decline >30 g/L during weeks 5-12 and 13-48 were more likely to achieve SVR than those who first developed such changes in weeks 0-4 or who never experienced them. CONCLUSION: Patients with HCV genotype 1 infection who develop anemia or experience a hemoglobin decline >30 g/L during weeks 5-48 of therapy achieve higher virological responses to pegylated interferon and ribavirin therapy that are unrelated to erythropoietin use.


Assuntos
Anemia/induzido quimicamente , Hepatite C Crônica/virologia , Interferon-alfa/efeitos adversos , Polietilenoglicóis/efeitos adversos , Ribavirina/efeitos adversos , Adolescente , Adulto , Idoso , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Hemoglobinas/metabolismo , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon alfa-2 , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Estudos Retrospectivos , Ribavirina/uso terapêutico , Resultado do Tratamento , Carga Viral
3.
J Hepatol ; 53(4): 616-23, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20619475

RESUMO

BACKGROUND & AIMS: The impact of fibrosis stage on chronic hepatitis C virus (HCV) treatment response was explored in CHARIOT, a study of high dose peginterferon alfa-2a (PEG-IFNalpha-2a) induction therapy in treatment naïve genotype 1 infection. METHODS: Eight hundred and ninety-six patients were randomised 1:1 to 360 microg (n=448) or 180 microg (n=448) PEG-IFNalpha-2a weekly with RBV 1000-1200 mg/day for 12 weeks followed by 36 weeks of 180 microg PEG-IFNalpha-2a weekly plus RBV 1000-1200 mg/day. Virological responses were assessed at week 4, 8, 12, 24, 48 (end of therapy), and 24 weeks following therapy (sustained virological response, SVR). As previously reported, there was no significant difference in SVR in the induction (53%) and standard (50%) arms, therefore the pooled study population was used for analysis of SVR and relapse. RESULTS: A marked step-wise decline in SVR was evident by fibrosis stage: F0 (70%); F1 (60%); F2 (51%); F3 (31%); F4 (10%) (p<0.0001). Early virological responses were lower among F3/4 patients, including rapid virological response (RVR) (21% vs. 34% for F3/4 and F0-2, respectively) (p=0.0072), and the RVR positive predictive value was also lower (63% vs. 80%). Virological relapse rates were similar in early disease stages (F0, 16%; F1, 23%; F2, 26%), but increased markedly in advanced fibrosis (F3, 50%; F4, 80%) (p<0.0001). Cumulative PEG-IFNalpha-2a and ribavirin doses were similar among patients with F3/4 and F0-2 within treatment arms through week 4, 8, 12, and week 24. CONCLUSIONS: Low virological response in hepatitis C genotype 1 patients with advanced fibrosis is not explained by inadequate cumulative PEG-IFN and ribavirin doses.


Assuntos
Antivirais/administração & dosagem , Hepatite C/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adolescente , Adulto , Idoso , Feminino , Genótipo , Hepatite C/genética , Humanos , Interferon alfa-2 , Cirrose Hepática/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Recidiva , Resultado do Tratamento
4.
Hepatology ; 50(4): 1045-55, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19676125

RESUMO

UNLABELLED: This study tested the hypothesis that high-dose peginterferon alfa-2a (PEG-IFNalpha-2a) for the first 12 weeks would increase early and sustained virological response (SVR) rates in patients with chronic hepatitis C genotype 1. Eight hundred ninety-six patients were randomized 1:1 to 360 microg (n = 448) or 180 microg (n = 448) PEG-IFNalpha-2a weekly plus ribavirin at 1000-1200 mg/day for 12 weeks, followed by 36 weeks of 180 microg PEG-IFNalpha-2a weekly plus ribavirin at 1000-1200 mg/day with 871 patients evaluable for the intention-to-treat analysis. Virological responses were assessed by TaqMan (limit of detection 15 IU/mL) at week 4, 8, 12, 24, 48 (end of therapy), and 24 weeks following therapy (SVR). Undetectable hepatitis C virus RNA rates were significantly higher among patients receiving high-dose induction therapy at week 4 (36% versus 26%, P < 0.005), week 8 (61% versus 50%, P < 0.005), and week 12 (74% versus 62%, P < 0.005). However, SVR was not significantly different between patients receiving high-dose (53%) and standard (50%) therapy. Significant baseline prognostic factors for SVR included age, sex, race, histological stage, and viral load. SVR was considerably higher among patients with no or minimal fibrosis (64% and 60%, respectively) compared to those with severe fibrosis/cirrhosis (28% and 24%, respectively). The frequency of serious adverse events and drug discontinuations were similar in both groups, whereas PEG-IFN dose modification, weight and appetite reduction, and grade IV neutropenia were significantly higher in the induction arm. CONCLUSION: Induction dosing with 360 microg/week PEG-IFNalpha-2a for 12 weeks was well tolerated and enhanced early virological response but not SVR rates. The high SVR rates in patients with minimal fibrosis highlight the benefit of early treatment in patients with hepatitis C virus genotype 1.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Antivirais/farmacologia , Povo Asiático/etnologia , População Negra/etnologia , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/etnologia , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Interferon-alfa/farmacologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/farmacologia , Proteínas Recombinantes , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Resultado do Tratamento , População Branca/etnologia
5.
Diabetes ; 53(11): 2921-30, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15504973

RESUMO

This study investigated the role of advanced glycation end products (AGEs) in mediating protein kinase C (PKC) isoform expression in diabetic nephropathy. In vitro, vascular smooth muscle cells incubated in a high-glucose (25-mmol/l) medium demonstrated translocation and increased expression of PKC-alpha as compared with those from a low-glucose (5-mmol/l) environment. Coincubation with the cross-link breaker ALT-711 and, to a lesser extent, with aminoguanidine, an inhibitor of AGE formation, attenuated the increased expression and translocation of PKC-alpha. Streptozotocin-induced diabetic rats were randomized to no treatment, treatment with ALT-711, or treatment with aminoguanidine. Diabetes induced increases in PKC-alpha as well as in the -betaI, -betaII, and -epsilon isoforms. Treatment with ALT-711 and aminoguanidine, which both attenuate renal AGE accumulation, abrogated these increases in PKC expression. However, translocation of phosphorylated PKC-alpha from the cytoplasm to the membrane was reduced only by ALT-711. ALT-711 treatment attenuated expression of vascular endothelial growth factor and the extracellular matrix proteins, fibronectin and laminin, in association with reduced albuminuria. Aminoguanidine had no effect on VEGF expression, although some reduction of fibronectin and laminin was observed. These findings implicate AGEs as important stimuli for the activation of PKC, particularly PKC-alpha, in the diabetic kidney, which can be directly inhibited by ALT-711.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Proteínas da Matriz Extracelular/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Tiazóis/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/patologia , Guanidinas/farmacologia , Córtex Renal/efeitos dos fármacos , Córtex Renal/patologia , Masculino , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteína Quinase C-alfa , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
6.
J Hypertens ; 23(1): 153-64, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15643138

RESUMO

OBJECTIVE: It has been postulated that vascular endothelial growth factor (VEGF) plays a role in the progression of renal injury. However, the role of other angiogenic factors and their receptors, such as the angiopoietins and Tie2, and in particular their relation to renoprotective therapies, such as agents that interrupt the renin-angiotensin system, have not been studied in the context of diabetes-related renal injury. DESIGN AND METHODS: Renal expression of VEGF, angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and their receptors, VEGF-R2 and Tie-2, were assessed using reverse transcription-polymerase chain reaction, immunohistochemistry and Western blotting, in control and streptozotocin diabetic rats, untreated or receiving the AT1 receptor antagonist, valsartan, or the AT2 receptor antagonist, PD123319. RESULTS: Diabetes was associated with increased gene and protein expression of VEGF, VEGF-R2, Ang-1, Ang-2 and Tie-2. AT1 receptor antagonism attenuated gene expression of these cytokines and receptors, yet PD123319, which had no effect on blood pressure, reduced VEGF-R2 and Ang-1 gene expression and decreased VEGF, Ang-1 and Ang-2 protein levels. CONCLUSIONS: In experimental diabetes, there is significant upregulation within the kidney of various angiogenic cytokines and their receptors. Furthermore, the effects of angiotensin II receptor blockade on these parameters is consistent with the VEGF-VEGF-R2 and angiopoietin-Tie-2 axes being modulated in the kidney by haemodynamic factors in the diabetic context.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Rim/fisiologia , Sistema Renina-Angiotensina/fisiologia , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Angiopoietina-1/genética , Angiopoietina-2/genética , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Expressão Gênica/fisiologia , Imidazóis/farmacologia , Masculino , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo , Receptor TIE-2/genética , Vasoconstritores/farmacologia
7.
J Hypertens ; 22(4): 767-74, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15126919

RESUMO

OBJECTIVE: Heparin inhibits vascular hypertrophy in angiotensin-induced hypertension, in addition to its well-known role in inhibiting injury-induced vascular smooth muscle proliferation. We tested whether hypertension and vascular hypertrophy could be reduced by heparin independently from the renin-angiotensin system. METHODS: Rats were made hypertensive with a one-kidney, one-clip (1K1C) procedure and received heparin from osmotic minipumps (0.3 mg/h per kg i.v.) or saline vehicle for 2 weeks. Blood pressure was measured by the tail-cuff method and vessel cross-sectional area was measured by morphometry in the aorta and mesenteric arteries. Proliferation was assessed with bromodeoxyuridine labelling. RESULTS: Blood pressure elevation and cardiovascular hypertrophy were evident in 1K1C rats. The media of mesenteric arteries was increased by 25%, and the media : lumen ratio by 35%, in hypertensive rats. DNA synthesis by smooth muscle cells in the mesenteric arteries was increased sevenfold in renal hypertension. Heparin treatment did not influence either the increase in blood pressure, the cardiovascular hypertrophy response or hypertension-mediated proliferation of arterial smooth muscle cells. CONCLUSIONS: These data suggest that the vascular hypertrophy mechanisms operating in 1K1C renal hypertension are not inhibited by heparin and thus are different from those in angiotensin-mediated hypertension. Identifying such mechanisms in the future will be important for devising appropriate intervention strategies in angiotensin-independent forms of vascular hypertrophy.


Assuntos
Heparina/uso terapêutico , Hipertensão Renal/metabolismo , Angiotensina II/farmacologia , Animais , Aorta Torácica/citologia , Aorta Torácica/metabolismo , Pressão Sanguínea , Peso Corporal/efeitos dos fármacos , Divisão Celular , DNA/biossíntese , Hipertrofia , Masculino , Artérias Mesentéricas/citologia , Artérias Mesentéricas/metabolismo , Músculo Liso Vascular/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos WKY , Fatores de Tempo
8.
Antivir Ther ; 17(5): 849-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22513456

RESUMO

BACKGROUND: On-treatment HCV viral load during early therapy with pegylated interferon (PEG-IFN) and ribavirin is highly predictive of sustained virological response (SVR). We sought to provide further refinement of this prediction through an extensive evaluation of the effect of HCV viral loads at weeks 4, 8 and 12 on SVR, including analysis by liver disease stage grouping. METHODS: A total of 309 patients with genotype 1 chronic HCV and recent liver biopsy enrolled in the CHARIOT study received 180 µg of PEG-IFN-α2a weekly with 1,000/1,200 mg of ribavirin daily. The probability of an SVR was estimated using baseline METAVIR fibrosis stage and HCV viral loads at weeks 4, 8 and 12. RESULTS: HCV RNA was undetectable in 27.5%, 50.3% and 62.6% of patients at weeks 4, 8 and 12, respectively. SVR was 80.0%, 76.8% and 72.4% among patients with undetectable HCV RNA at weeks 4, 8 and 12, respectively. SVR decreased in a progressive fashion with increasing HCV viral loads at each early time point, but was similar for patients with HCV viral load <15 IU/ml, 15-100 IU/ml and 100-1,000 IU/ml. The effect of fibrosis stage on SVR was modest for patients with HCV viral load <1,000 IU/ml at week 4, but more marked for those with week 4 HCV viral load >1,000 IU/ml, and all HCV viral load categories at weeks 8 and 12. CONCLUSIONS: A combination of baseline fibrosis stage and on-treatment HCV viral load at early time points provides improved estimates for treatment response in patients with chronic HCV genotype 1.


Assuntos
Genótipo , Hepacivirus/genética , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Carga Viral , Adulto , Antivirais/uso terapêutico , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Tempo , Resultado do Tratamento
9.
Antivir Ther ; 16(2): 173-80, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21447866

RESUMO

BACKGROUND: We examined the detection of low-level viraemia at week 24 as a predictor of sustained virological response (SVR) and viral relapse/breakthrough, and the agreement between the Roche Cobas TaqMan™ HCV RNA assay (TaqMan) and Roche Cobas(®) Amplicor HCV qualitative assay (Amplicor; both Roche Molecular Diagnostics, Pleasanton, CA, USA) for detection of low-level viraemia. METHODS: A total of 871 treatment-naive HCV genotype 1 patients participating in an induction-dose pegylated interferon therapy study had virological responses assessed using TaqMan. A total of 151 patients with HCV RNA levels ≤500 IU/ml had samples tested in parallel using the Amplicor and TaqMan assays. RESULTS: SVR was significantly lower and relapse/breakthrough significantly higher in patients with low-level residual viraemia at week 24 compared with those who had undetectable viraemia: SVR was 72%, 29% and 14% (P<0.0001) and relapse/breakthrough 28%, 71% and 86% (P<0.0001) in patients with viraemia that was undetectable, detectable <15 IU/ml and detectable 15-<50 IU/ml, respectively, at week 24. The negative predictive value (NPV) for a week-24 virological response for SVR was 86%, 90% and 90% using TaqMan cutoffs of undetectable, <15 IU/ml and <50 IU/ml, respectively. The percentage agreement between Amplicor and TaqMan was similarly high for TaqMan cutoffs of 50 IU/ml and 15 IU/ml, but lower for undetectable viraemia (83%, 83% and 70%, respectively). CONCLUSIONS: These data emphasize the importance of achieving undetectable HCV RNA during pegylated interferon therapy to maximize SVR; however, the current 24-week stopping rule of undetectable HCV RNA appears too stringent when using sensitive PCR assays given the observed lower NPV for SVR using the TaqMan undetectable cutoff. Our data also suggest that a TaqMan <15 IU/ml result is comparable to an Amplicor-negative result (that is, below the assay cutoff value) when monitoring viral response.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Viremia/tratamento farmacológico , Adolescente , Adulto , Idoso , Antivirais/administração & dosagem , Quimioterapia Combinada , Genótipo , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Kit de Reagentes para Diagnóstico , Proteínas Recombinantes , Ribavirina/administração & dosagem , Resultado do Tratamento , Carga Viral , Viremia/virologia , Adulto Jovem
10.
J Am Soc Nephrol ; 14(12): 3061-71, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14638905

RESUMO

A link between angiotensin II and cell proliferation has previously been reported. However, there remains controversy as to the role of the individual angiotensin II receptor subtypes in mediating these effects and their link to angiogenic cytokines and their receptors. Male Sprague-Dawley rats were infused with either angiotensin II or vehicle for 14 d at a dose of 58.3 ng/min. Angiotensin II-infused rats received no treatment, an AT(1) receptor antagonist valsartan (30 mg/kg per d), or an AT(2) receptor antagonist PD123319 (830 ng/min). Gene expression of vascular endothelial growth factor (VEGF) and receptor VEGF-R2, as well as Tie-2 and its ligands angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) were assessed by reverse transcription-PCR. Protein expression was assessed by Western blotting and immunohistochemistry. Gene and protein expression of VEGF, Ang-1, and Ang-2 were increased by angiotensin II infusion. Valsartan and PD123319 attenuated angiotensin II-associated increases in VEGF gene and protein expression. Ang-1 and Ang-2 gene but not protein expression were reduced by both treatments. These changes occurred in the context of attenuation of angiotensin II-induced glomerular cell proliferation by both valsartan and PD123319. In situ hybridization and immunohistochemical studies localized VEGF, Ang-1, and Ang-2 expression to the epithelial cells of the glomerulus, and VEGF-R2 and Tie-2 receptors to the endothelial cells of the kidney. These findings extend the increasing evidence that the AT(2) receptor, in addition to the AT(1) receptor subtype, plays an important role in mediating the proliferative actions of angiotensin II in the kidney.


Assuntos
Angiopoietinas/biossíntese , Angiotensina II/fisiologia , Receptor Tipo 1 de Angiotensina/fisiologia , Receptor Tipo 2 de Angiotensina/fisiologia , Fatores de Crescimento do Endotélio Vascular/biossíntese , Angiotensina II/administração & dosagem , Animais , Expressão Gênica , Rim/metabolismo , Masculino , Biossíntese de Proteínas , Ratos , Ratos Sprague-Dawley
11.
Am J Pathol ; 163(3): 879-87, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12937129

RESUMO

There is evidence that angiotensin II, vascular endothelial growth factor (VEGF), angiopoietins, and their cognate receptors participate in retinal angiogenesis. We investigated whether angiotensin type 2-receptor blockade (AT2-RB) reduces retinal angiogenesis and alters the expression of VEGF/VEGF-R2 and angiopoietin-Tie2. Retinopathy of prematurity (ROP) was induced in Sprague Dawley (SD) rats by exposure to 80% oxygen from postnatal (P) days 0 to 11, followed by 7 days in room air. ROP shams were in room air from P0-18. A group of ROP rats received the AT2-RB, PD123319, by mini-osmotic pump (5 mg/kg/day) from P11-18 (angiogenesis period). Evaluation of the retinal status of the AT2 receptor indicated that this receptor, as assessed by real-time PCR, immunohistochemistry, and in vitro autoradiography, was present in the retina, was more abundant than the AT1 receptor in the neonatal retina, and was increased in the ROP model. AT2-RB reduced retinal angiogenesis. VEGF and VEGF-R2 mRNA were increased in ROP and localized to blood vessels, ganglion cells, and the inner nuclear layer, and were decreased by PD123319. Angiopoietin2 and Tie2, but not angiopoietin1 mRNA were increased with ROP, and angiopoietin2 was reduced with PD123319. This study has identified a potential retinoprotective role for AT2-RB possibly mediated via interactions with VEGF- and angiopoietin-dependent pathways.


Assuntos
Indutores da Angiogênese/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Linfocinas/metabolismo , Neovascularização Patológica/fisiopatologia , Receptores de Angiotensina/metabolismo , Doenças Retinianas/fisiopatologia , Vasos Retinianos/fisiopatologia , Envelhecimento/metabolismo , Angiopoietina-2 , Animais , Animais Recém-Nascidos , Autorradiografia , Sistemas Computacionais , Fatores de Crescimento Endotelial/genética , Imuno-Histoquímica , Hibridização In Situ , Peptídeos e Proteínas de Sinalização Intercelular/genética , Linfocinas/genética , Neovascularização Patológica/patologia , Oxigênio , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Retina/metabolismo , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/patologia , Vasos Retinianos/patologia , Fator A de Crescimento do Endotélio Vascular , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Fatores de Crescimento do Endotélio Vascular
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