Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Gastroenterology ; 165(1): 149-161.e7, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37004887

RESUMEN

BACKGROUND & AIMS: Tumor necrosis factor inhibitors, including infliximab and adalimumab, are a mainstay of pediatric Crohn's disease therapy; however, nonresponse and loss of response are common. As combination therapy with methotrexate may improve response, we performed a multicenter, randomized, double-blind, placebo-controlled pragmatic trial to compare tumor necrosis factor inhibitors with oral methotrexate to tumor necrosis factor inhibitor monotherapy. METHODS: Patients with pediatric Crohn's disease initiating infliximab or adalimumab were randomized in 1:1 allocation to methotrexate or placebo and followed for 12-36 months. The primary outcome was a composite indicator of treatment failure. Secondary outcomes included anti-drug antibodies and patient-reported outcomes of pain interference and fatigue. Adverse events (AEs) and serious AEs (SAEs) were collected. RESULTS: Of 297 participants (mean age, 13.9 years, 35% were female), 156 were assigned to methotrexate (110 infliximab initiators and 46 adalimumab initiators) and 141 to placebo (102 infliximab initiators and 39 adalimumab initiators). In the overall population, time to treatment failure did not differ by study arm (hazard ratio, 0.69; 95% CI, 0.45-1.05). Among infliximab initiators, there were no differences between combination and monotherapy (hazard ratio, 0.93; 95% CI, 0.55-1.56). Among adalimumab initiators, combination therapy was associated with longer time to treatment failure (hazard ratio, 0.40; 95% CI, 0.19-0.81). A trend toward lower anti-drug antibody development in the combination therapy arm was not significant (infliximab: odds ratio, 0.72; 95% CI, 0.49-1.07; adalimumab: odds ratio, 0.71; 95% CI, 0.24-2.07). No differences in patient-reported outcomes were observed. Combination therapy resulted in more AEs but fewer SAEs. CONCLUSIONS: Among adalimumab but not infliximab initiators, patients with pediatric Crohn's disease treated with methotrexate combination therapy experienced a 2-fold reduction in treatment failure with a tolerable safety profile. CLINICALTRIALS: gov, Number: NCT02772965.


Asunto(s)
Metotrexato , Inhibidores del Factor de Necrosis Tumoral , Niño , Humanos , Femenino , Adolescente , Masculino , Metotrexato/efectos adversos , Adalimumab/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Infliximab/efectos adversos , Factor de Necrosis Tumoral alfa , Resultado del Tratamiento
2.
Pediatr Dermatol ; 39(4): 563-566, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35342990

RESUMEN

Paradoxically, immunosuppressive therapy for inflammatory bowel disease (IBD) can induce psoriasiform or eczematous eruptions. This case-control study identified infliximab exposure, Crohn's disease, and history of inflammatory skin conditions as significant risk factors for these eruptions in children with IBD. Our results also showed possible trends in age and race.


Asunto(s)
Exantema , Enfermedades Inflamatorias del Intestino , Adalimumab/efectos adversos , Estudios de Casos y Controles , Niño , Exantema/inducido químicamente , Humanos , Inmunosupresores/efectos adversos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/efectos adversos , Factor de Necrosis Tumoral alfa
3.
J Pediatr Gastroenterol Nutr ; 72(4): 574-578, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33346578

RESUMEN

ABSTRACT: Adult studies demonstrate the co-existence of nonalcoholic fatty liver disease (NAFLD) and inflammatory bowel disease (IBD) without traditional risk factors. Data in children with IBD are lacking. Here, we sought to establish the prevalence of NAFLD in a single-center pediatric IBD cohort, and identify potential risk factors. After institutional review board approval, we enrolled children with IBD who underwent routine abdominal magnetic resonance enterography. Proton density fat fraction (PDFF) was then estimated on magnetic resonance enterography. A total of 83 patients with IBD were identified and PDFF maps completed. Five (6%) were found to have PDFF >5%, meeting criteria for NAFLD. Compared to the patients with IBD without NAFLD, none of the evaluated risk factors including age, sex, diagnosis, time since diagnosis, medication, median alanine aminotransferase, and weight status were statistically significant. Our findings demonstrate the occult nature of NAFLD in pediatric IBD. The prevalence is not at variance with what is expected in general teenage populations.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Enfermedad del Hígado Graso no Alcohólico , Adolescente , Adulto , Niño , Humanos , Enfermedades Inflamatorias del Intestino/complicaciones , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Factores de Riesgo
4.
EGEMS (Wash DC) ; 7(1): 51, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31646151

RESUMEN

OBJECTIVE: To implement a quality improvement based system to measure and improve data quality in an observational clinical registry to support a Learning Healthcare System. DATA SOURCE: ImproveCareNow Network registry, which as of September 2019 contained data from 314,250 visits of 43,305 pediatric Inflammatory Bowel Disease (IBD) patients at 109 participating care centers. STUDY DESIGN: The impact of data quality improvement support to care centers was evaluated using statistical process control methodology. Data quality measures were defined, performance feedback of those measures using statistical process control charts was implemented, and reports that identified data items not following data quality checks were developed to enable centers to monitor and improve the quality of their data. PRINCIPAL FINDINGS: There was a pattern of improvement across measures of data quality. The proportion of visits with complete critical data increased from 72 percent to 82 percent. The percent of registered patients improved from 59 percent to 83 percent. Of three additional measures of data consistency and timeliness, one improved performance from 42 percent to 63 percent. Performance declined on one measure due to changes in network documentation practices and maturation. There was variation among care centers in data quality. CONCLUSIONS: A quality improvement based approach to data quality monitoring and improvement is feasible and effective.

5.
Inflamm Bowel Dis ; 23(12): 2104-2108, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29140940

RESUMEN

BACKGROUND: Infliximab (IFX) infusion may lead to development of anti-IFX antibodies, and subsequent infusion reactions (IRs). The safety of rapid IFX infusion administered over 60 minutes has been under-investigated in children with inflammatory bowel disease. In a multicenter study, the frequency and nature of rapid infusion-associated IRs were examined. METHODS: The medical records of all consecutive children with inflammatory bowel disease receiving rapid IFX infusions between January 2014 and December 2016 were reviewed. Poisson regression analysis was used to identify possible associated factors with IRs. RESULTS: A total of 4120 rapid infusions for 453 children (median age 16 yrs [interquartile range 13.8-17.8], 289 males, 374 with Crohn's disease) were included. One hundred thirty-five participants (29.8%) received rapid IFX infusion for induction and maintenance while the rest received rapid IFX infusion after a median of 5 (interquartile range 4-9) standard infusions. The median dose of IFX using rapid protocol was 8 mg/kg/infusion (interquartile range 6-10). Two hundred sixty-seven (59%) patients received 1 or more premedications and 161 (35.5%) participants received concomitant immunosuppression. Twenty-one participants (4.6%) had IRs with rapid infusions and 2 participants discontinued IFX because of IRs (0.4%). Antihistamine premedications were associated with less frequent IR (adjusted relative risk = 0.30; 95% confidence interval, 0.14-0.64; P = 0.002). CONCLUSIONS: In children with inflammatory bowel disease, rapid IFX infusion administered over 60 minutes is safe and well-tolerated. Antihistamine premedications may reduce frequency of IRs (see Video Abstract, Supplemental Digital Content 1, http://links.lww.com/IBD/B632).


Asunto(s)
Hipersensibilidad a las Drogas/epidemiología , Fármacos Gastrointestinales/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/uso terapéutico , Adolescente , Niño , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Masculino , Pronóstico , Inducción de Remisión , Estados Unidos/epidemiología
6.
J Rheumatol ; 44(11): 1624-1631, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28916545

RESUMEN

OBJECTIVE: Accumulating evidence links juvenile idiopathic arthritis (JIA) to nonhost factors such as gut microbes. We hypothesize that children with new-onset JIA have increased intestinal bacterial translocation and circulating lipopolysaccharide (LPS). METHODS: We studied systemic treatment-naive patients with JIA [polyarticular JIA, n = 22, oligoarticular JIA, n = 31, and spondyloarthropathies (SpA), n = 16], patients with established inflammatory bowel disease-related arthritis (IBD-RA, n = 11), and 34 healthy controls. We determined circulating IgG reactivity against LPS, LPS-binding protein (LBP), α-1-acid glycoprotein (α-1AGP), and C-reactive protein (CRP) in plasma or serum from these patients and controls. Juvenile Arthritis Disease Activity Score (JADAS-27) was calculated for patients with JIA. RESULTS: Circulating anticore LPS antibody concentrations in patients with polyarticular JIA (p = 0.001), oligoarticular JIA (p = 0.024), and SpA (p = 0.001) were significantly greater than in controls, but there were no significant intergroup differences. Circulating LBP concentrations were also significantly greater in patients with polyarticular JIA (p = 0.001), oligoarticular JIA (p = 0.002), and SpA (p = 0.006) than controls, as were α-1AGP concentrations (p = 0.001, 0.001, and 0.003, respectively). No differences were observed between controls and patients with IBD-RA in any of the assays. Circulating concentrations of LBP and α-1AGP correlated strongly with CRP concentrations (r = 0.78 and r = 0.66, respectively). Anticore LPS antibody levels and CRP (r = 0.26), LBP (r = 0.24), and α-AGP (r = 0.22) concentrations had weaker correlations. JADAS-27 scores correlated with LBP (r = 0.66) and α-1AGP concentrations (r = 0.58). CONCLUSION: Children with polyarticular JIA, oligoarticular JIA, and SpA have evidence of increased exposure to gut bacterial products. These data reinforce the concept that the intestine is a source of immune stimulation in JIA.


Asunto(s)
Artritis Juvenil/sangre , Inmunoglobulina G/inmunología , Inflamación/sangre , Lipopolisacáridos/inmunología , Adolescente , Artritis Juvenil/inmunología , Niño , Preescolar , Femenino , Humanos , Inflamación/inmunología , Masculino
7.
J Pediatr Gastroenterol Nutr ; 64(4): 575-579, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27299424

RESUMEN

OBJECTIVES: The aim of the study was to use pharmacy benefit management (PBM) prescription claims data to assess refill adherence in pediatric inflammatory bowel disease (IBD) and correlate adherence with clinical outcomes in pediatric IBD. METHODS: We identified 362 pediatric patients with IBD seen at Washington University from 9/1/2012 to 8/31/2013 and matched them within Express Scripts' member eligibility files for clients allowing use of prescription drug data for research purposes. Maintenance IBD medication possession ratios (MPR) were determined through PBM prescription claims data and chart review. Demographic and prospectively captured physician global assessments (PGA) were retrospectively extracted from the medical record. MPR was analyzed as continuous data and also dichotomized as greater or less than 80%. RESULTS: Among our 362 patients, we matched 228 (63%) within Express Scripts' eligibility data files. Of those, 78 patients were continuously eligible for benefits and had at least one outpatient prescription IBD medication prescribed. Their mean MPR was 0.63 ±â€Š0.31 (standard deviation) and 40% had an MPR ≥80%. Patients in clinical remission had a higher mean MPR than those with an active PGA (0.72 ±â€Š0.28 vs 0.51 ±â€Š0.32, P = 0.002) and patients whose MPR were ≥80% were more likely to have a PGA of remission than those with whose MPR were <80% (84% vs 43%, P = <0.001). CONCLUSIONS: We found a significant association between refill adherence and clinical remission. Nonadherence was common and was more common in adolescents. Use of PBM databases to identify and intervene on patients with poor adherence may improve outcomes in pediatric IBD.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Cumplimiento de la Medicación/estadística & datos numéricos , Adolescente , Niño , Colitis Ulcerosa/diagnóstico , Enfermedad de Crohn/diagnóstico , Prescripciones de Medicamentos , Quimioterapia Combinada , Femenino , Humanos , Quimioterapia de Inducción , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
8.
Pediatr Qual Saf ; 2(4): e029, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30229166

RESUMEN

INTRODUCTION: Celiac disease (CD) management involves lifelong adherence to a gluten-free diet, making the dietician a key member in CD care. However, our institution lacked a standardized process for dietary consultation in newly diagnosed CD. METHODS: To understand provider CD care preferences, a 24-1 fractional factorial conjoint analysis was performed. Attributes studied (2 levels each) included type of initial follow-up gastroenterology (GI) provider, interval from diagnosis to follow-up, concurrence of initial dietary consultation with gastroenterology visit, and on-going follow-up GI provider. CD care was standardized in July 2014 to facilitate concurrent visits with the clinician and dietician during the same clinical session. Changes to mean time of dietary consultation and reliability of dietary consultation were monitored using an individual-control and G-control chart, respectively. Standard control chart rules were followed. RESULTS: Conjoint analysis identified shorter time to initial follow-up visit and concurrent GI/dietician visits as more important attributes in newly diagnosed CD subjects' care. Types of follow-up provider during first or subsequent visits were identified as less important attributes. After initiation of a standardized follow-up process, a special cause was identified in December 2015 with a decrease in the mean time to dietary consultation from 30 to 20 days. In addition, standardized follow-up resulted in a more reliable process as evident by a special cause on the G-control chart in February 2015. CONCLUSION: Conjoint analysis identified attributes thought to be important in CD follow-up care. After redesign of our care process, a decrease in time to dietary consultation with improved reliability was observed.

9.
J Pediatr Gastroenterol Nutr ; 55(6): 679-88, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22699837

RESUMEN

OBJECTIVES: Variations in chronic illness care are common in our health care system and may lead to suboptimal outcomes. Specifically, inconsistent use and suboptimal medication dosing have been demonstrated in the care of patients with inflammatory bowel disease (IBD). Quality improvement (QI) efforts have improved outcomes in conditions such as asthma and diabetes mellitus, but have not been well studied in IBD. We hypothesized that QI efforts would lead to improved outcomes in our pediatric IBD population. METHODS: A QI team was formed within our IBD center in 2005. By 2007, we began prospectively capturing physician global assessment (PGA) and patient-reported global assessment. Significant QI interventions included creating evidence-based medication guidelines, joining a national QI collaborative, initiation of preclinic planning, and monitoring serum 25-hydroxyvitamin D. RESULTS: From 2007 to 2010, 505 patients have been followed at our IBD center. During this time, the frequency of patients in clinical remission increased from 59% to 76% (P < 0.05), the frequency of patients who report that their global assessment is >7 increased from 69% to 80% (P < 0.05), and the frequency of patients with a Short Pediatric Crohn's Disease Activity Index (sPCDAI) <15 increased from 60% to 77% (P < 0.05). The frequency of repeat steroid use decreased from 17% to 10% (P < 0.05). We observed an association between the use of a vitamin D supplement (P = 0.02), serum 25-hydroxyvitamin D (P < 0.05), and quiescent disease activity. CONCLUSIONS: Our results show that significant improvements in patient outcomes are associated with QI efforts that do not rely on new medication or therapies.


Asunto(s)
Atención a la Salud/normas , Enfermedades Inflamatorias del Intestino/terapia , Mejoramiento de la Calidad , Esteroides/uso terapéutico , Vitamina D/uso terapéutico , Adolescente , Niño , Conducta Cooperativa , Suplementos Dietéticos , Femenino , Guías como Asunto , Humanos , Enfermedades Inflamatorias del Intestino/sangre , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Masculino , Estudios Prospectivos , Inducción de Remisión , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Vitamina D/análogos & derivados , Vitamina D/sangre
10.
Inflamm Bowel Dis ; 17(12): 2443-55, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21381154

RESUMEN

BACKGROUND: Ileal involvement in Crohn's disease (CD) is associated with NOD2 mutations and granulocyte-macrophage colony stimulating factor autoantibodies (GM-CSF Ab), and GM-CSF blockade promotes ileitis in Nod2/Card15-deficient (C15KO) mice. RALDH2-expressing dendritic cells (DC) and IL-4 promote CCR9 imprinting and small bowel homing of T lymphocytes, in conjunction with CCL25 expression by ileal epithelial cells (IEC). We hypothesized that GM-CSF neutralization promotes ileal disease by modulating expression of CCL25 by IEC and CCR9 by T lymphocytes via Nod2-dependent and independent pathways. METHODS: CCL25 and CCR9 expression were determined in pediatric CD patients stratified by GM-CSF Ab. Ileitis was induced in C15KO mice via GM-CSF Ab administration followed by nonsteroidal antiinflammatory drug (NSAID) exposure, and expression of CCL25, CCR9, FOXP3, intracellular cytokines, and RALDH2 was determined in IEC and immune cell populations. RESULTS: The frequency of CCL25(+) IEC and CCR9(+) T lymphocytes was increased in CD patients with elevated GM-CSF Ab. In the murine model, GM-CSF blockade alone induced IEC CCL25 expression, and reduced the frequency of mesenteric lymph node (MLN) CD4(+) FOXP3(+) cells, while Card15 deficiency alone enhanced MLN DC RALDH2 expression. Both GM-CSF neutralization and Card15 deficiency were required for downregulation of MLN DC IL-10 expression; under these conditions NSAID exposure led to an expansion of IL-4(+) and IL-17(+) CCR9(+) lymphocytes in the ileum. CONCLUSIONS: GM-CSF prevents ileal expansion of CCR9(+) lymphocytes via Nod2-dependent and independent pathways. CCR9 blockade may be beneficial in CD patients with elevated GM-CSF Ab.


Asunto(s)
Enfermedad de Crohn/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Ileítis/patología , Linfocitos/patología , Proteína Adaptadora de Señalización NOD2/fisiología , Receptores CCR/metabolismo , Aldehído Oxidorreductasas/genética , Aldehído Oxidorreductasas/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Quimiocinas CC/genética , Quimiocinas CC/metabolismo , Niño , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos , Ileítis/inmunología , Ileítis/metabolismo , Técnicas para Inmunoenzimas , Interleucina-10/genética , Interleucina-10/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Masculino , Ratones , Ratones Noqueados , Mutación/genética , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores CCR/genética
11.
J Hepatol ; 40(6): 942-51, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15158334

RESUMEN

BACKGROUND/AIMS: The cirrhotic liver manifests dysregulated hepatocyte growth by poor regenerative capacity, formation of regenerative nodules, and malignant transformation to hepatocellular carcinoma. The purpose of this study was to determine if dysregulated hepatocyte growth occurs through deficient apoptosis. METHODS: Hepatocytes were isolated from normal and CCl(4)-treated mice and treated with TGFbeta, TNFalpha, and UV-C, known apoptotic agents. RESULTS: Cirrhotic hepatocytes were less sensitive to TGFbeta- (45+/-5 vs. 15+/-3%; P<0.003), TNFalpha- (59+/-21 vs. 21+/-8%; P=0.02), and UV-C-induced (31+/-4 vs. 17+/-4%; P<0.03) apoptosis compared to normal hepatocytes. In normal hepatocytes, TGFbeta-induced apoptosis occurred through a ROS-, MPT-, and caspase-dependent pathway. Cirrhotic hepatocytes lacked caspase activation, had decreased procaspase-8 expression, failed to undergo the MPT, and had increased basal ROS activity compared to normal hepatocytes. After treatment with trolox, an antioxidant that reduced basal ROS activity, cirrhotic hepatocytes underwent apoptosis in response to TGFbeta treatment. CONCLUSIONS: These findings suggest that increased ROS activity in cirrhotic hepatocytes plays a critical role in mediating cirrhotic hepatocyte resistance to apoptosis. Cirrhotic hepatocyte resistance to TGFbeta-induced apoptosis is ROS-dependent and is a mechanism of dysregulated growth in the chronically inflamed liver.


Asunto(s)
Apoptosis/efectos de los fármacos , Cirrosis Hepática Experimental/patología , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Animales , Intoxicación por Tetracloruro de Carbono/patología , Caspasas/metabolismo , Técnicas de Cultivo de Célula , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Inmunohistoquímica , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/fisiología , Masculino , Ratones , Ratones Endogámicos BALB C , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/fisiología , Permeabilidad
12.
Biochem Biophys Res Commun ; 313(3): 546-51, 2004 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-14697224

RESUMEN

TGFbeta controls hepatocyte growth through cell cycle arrest and apoptosis, and resistance to TGFbeta is a mechanism of malignant transformation. The aim of this study was to assess differences in TGFbeta-mediated growth inhibition in normal and cirrhotic hepatocytes. Cirrhosis was induced in mice and normal and cirrhotic hepatocytes were isolated by collagenase perfusion and treated with or without TGFbeta (5 ng/ml). DNA synthesis, Smad protein expression, and DNA binding activity were determined. TGFbeta reduced DNA synthesis to a greater degree in normal hepatocytes than in cirrhotic hepatocytes (87% vs. 68%; p<0.05). Smad protein expression was decreased in cirrhotic hepatocytes and Smad 2/3/4 complex formation was suppressed. Furthermore, cirrhotic hepatocytes had decreased DNA binding activity at 120 min following TGFbeta treatment. In conclusion, decreased Smad protein expression may impair TGFbeta-mediated growth inhibition in cirrhotic hepatocytes.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Regulación hacia Abajo , Hepatocitos/metabolismo , Transactivadores/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Transporte Activo de Núcleo Celular , Animales , Western Blotting , División Celular , Transformación Celular Neoplásica , Colagenasas/metabolismo , ADN/metabolismo , Proteínas de Unión al ADN/biosíntesis , Fibrosis , Masculino , Ratones , Ratones Endogámicos BALB C , Unión Proteica , Transducción de Señal , Proteínas Smad , Proteína Smad2 , Proteína smad3 , Proteína Smad4 , Timidina/química , Factores de Tiempo , Transactivadores/biosíntesis
13.
J Surg Res ; 114(2): 110-7, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14559434

RESUMEN

INTRODUCTION: Cholestasis activates nuclear factor kappa B (NFkappaB), which is involved in both hepatocyte proliferation and apoptosis, depending on the cellular microenvironment. We hypothesized that NFkappaB inhibition would decrease hepatocyte proliferation and potentiate hepatocyte apoptosis in a rat model of extrahepatic biliary obstruction. AIM: To determine if NFkappaB inhibition concomitantly decreases hepatocyte proliferation and increases apoptosis in obstructive jaundice. MATERIALS AND METHODS: Male Sprague-Dawley rats underwent either sham operation or bile-duct ligation (BDL) combined with portal vein injection of vehicle or 6 x 10(9) particles of an adenovirus carrying either the control luciferase or the IkappaB super-repressor (AdIkappaBSR) transgenes. Liver was harvested 3, 5, and 7 days after sham operation or BDL, and immunohistochemistry for proliferating cell nuclear antigen and terminal dUTP nick end-labeling was performed for detection of DNA synthesis and apoptosis, respectively. RESULTS: Increased serum total bilirubin and hematoxylin and eosin-stained liver sections confirmed cholestasis in BDL animals. Western blot analysis demonstrated IkappaBSR protein expression in AdIkappaBSR-infected animals only. At day 7, NFkappaB inhibition decreased hepatocyte DNA synthesis in BDL rats compared to both adenovirus carrying the control luciferase and vehicle-treated controls. Apoptosis was increased in BDL vehicle-treated animals compared to sham-operation animals, but NFkappaB inhibition did not alter hepatocyte apoptosis in the BDL group. CONCLUSION: In obstructive cholestasis, NFkappaB is required for hepatocyte proliferation, but does not augment apoptosis.


Asunto(s)
Apoptosis/fisiología , Colestasis/patología , Colestasis/terapia , Terapia Genética/métodos , Hepatocitos/patología , FN-kappa B/antagonistas & inhibidores , Adenoviridae/genética , Animales , Conductos Biliares/fisiología , Biomarcadores/sangre , División Celular , Modelos Animales de Enfermedad , Genes Reporteros , Proteínas I-kappa B/genética , Luciferasas/genética , Masculino , Inhibidor NF-kappaB alfa , Ratas , Ratas Sprague-Dawley
14.
Surgery ; 132(3): 441-9, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12324757

RESUMEN

BACKGROUND: During hepatic regeneration, transforming growth factor (TGF)-beta1 messenger RNA increases after the initial cycle of DNA synthesis, and it may control hepatocyte growth by inducing apoptosis. TGF-beta1 also induces c-Jun, a potential proapoptotic transcription factor. We hypothesized that autocrine expression of activated TGF-beta1 (Ad5aTGF-beta1) would increase c-jun expression in rat liver and limit hepatic regeneration by inducing apoptosis. METHODS: Male rats (175 to 200 g) received portal venous injections with adenoviruses expressing either luciferase (Ad5Luc), as a control, or Ad5aTGF-beta1 at a dose of 6 x 10(9) plaque-forming units. Livers were harvested 24 or 48 hours after injection and nuclear extracts and total RNA isolated. TGF-beta1 expression was confirmed by Northern blot analysis in all TGF-beta1-injected rats. RESULTS: A 2.5-fold increase in c-jun mRNA expression was detected in Ad5aTGF-beta1-infected rats compared with control rats. Transcriptional activity was assessed with an AP-1-responsive-reporter gene that increased 3-fold in rat primary hepatocytes infected with Ad5aTGF-beta1. C-Jun N-terminal kinase activity also increased 6- to 7-fold in Ad5aTGF-beta1-treated rats 24 and 48 hours after injection. Ad5aTGF-beta1-injected rats demonstrated increased AP-1 binding activity compared with Ad5Luc rats. Hepatocytes infected in vitro with Ad5aTGF-beta1 demonstrated increased apoptosis compared with Ad5Luc-infected hepatocytes (47% vs 27%) 36 hours after infection. Dual adenoviral infection with Ad5aTGF-beta1 and a dominant-negative c-Jun (Ad5TAM67) decreased AP-1-induced Ad5Luc activity but not hepatocyte apoptosis (46% with dominant-negative c-Jun and 47% without). CONCLUSIONS: These data demonstrate that TGF-beta1 induces c-Jun, but c-Jun is not proapoptotic in hepatocytes.


Asunto(s)
Hepatocitos/patología , Proteínas Proto-Oncogénicas c-jun/fisiología , Factor de Crecimiento Transformador beta/fisiología , Adenoviridae/genética , Animales , Masculino , Proteínas Proto-Oncogénicas c-jun/genética , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Factor de Transcripción AP-1/metabolismo , Transcripción Genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...