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1.
Gastroenterology ; 156(5): 1368-1380.e10, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30552895

RESUMO

BACKGROUND & AIMS: Bacterial infections are common and life-threatening in patients with cirrhosis. Little is known about the epidemiology of bacterial infections in different regions. We performed a multicenter prospective intercontinental study to assess the prevalence and outcomes of bacterial and fungal infections in patients with cirrhosis. METHODS: We collected data from 1302 hospitalized patients with cirrhosis and bacterial or fungal infections at 46 centers (15 in Asia, 15 in Europe, 11 in South America, and 5 in North America) from October 2015 through September 2016. We obtained demographic, clinical, microbiology, and treatment data at time of diagnosis of infection and during hospitalization. Patients were followed until death, liver transplantation, or discharge. RESULTS: The global prevalence of multidrug-resistant (MDR) bacteria was 34% (95% confidence interval 31%-37%). The prevalence of MDR bacteria differed significantly among geographic areas, with the greatest prevalence in Asia. Independent risk factors for infection with MDR bacteria were infection in Asia (particularly in India), use of antibiotics in the 3 months before hospitalization, prior health care exposure, and site of infection. Infections caused by MDR bacteria were associated with a lower rate of resolution of infection, a higher incidence of shock and new organ failures, and higher in-hospital mortality than those caused by non-MDR bacteria. Administration of adequate empirical antibiotic treatment was independently associated with improved in-hospital and 28-day survival. CONCLUSIONS: In a worldwide study of hospitalized patients, we found a high prevalence of infection with MDR bacteria in patients with cirrhosis. Differences in the prevalence of MDR bacterial infections in different global regions indicate the need for different empirical antibiotic strategies in different continents and countries. While we await new antibiotics, effort should be made to decrease the spread of MDR bacteria in patients with cirrhosis.


Assuntos
Infecções Bacterianas/epidemiologia , Saúde Global , Cirrose Hepática/epidemiologia , Adulto , Idoso , Antibacterianos/uso terapêutico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Infecções Bacterianas/terapia , Estudos Transversais , Farmacorresistência Bacteriana Múltipla , Feminino , Mortalidade Hospitalar , Humanos , Cirrose Hepática/microbiologia , Cirrose Hepática/mortalidade , Cirrose Hepática/terapia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Micoses/epidemiologia , Micoses/microbiologia , Micoses/mortalidade , Micoses/terapia , Prevalência , Prognóstico , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo
2.
Nephrol Dial Transplant ; 35(9): 1554-1561, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30887050

RESUMO

BACKGROUND: Hepatorenal syndrome type 1 (HRS-1), a form of acute kidney injury (AKI) in cirrhosis, has a median survival of days to weeks if untreated. The impact of reduction in AKI stage on overall survival in cirrhosis, independent of HRS reversal, is unclear. METHODS: The Randomized, placEbo-controlled, double-blind study to confirm the reVERSal of HRS-1 with terlipressin study assessed terlipressin versus placebo, both with albumin, as treatment for HRS-1 for ≤14 days. Renal dysfunction severity was categorized by AKI stage at enrollment. Baseline patient characteristics were evaluated as predictors of AKI improvement using a multivariate model; the association between AKI stage reduction and 90-day survival was assessed using linear regression. RESULTS: A total of 184 patients (terlipressin: n = 91; placebo: n = 93) with similar numbers in AKI Stages 1-3 (terlipressin/placebo, Stage 1: n = 25/26; Stage 2: n = 35/33; Stage 3: n = 31/34) were included. Predictors of AKI improvement were absence of alcoholic hepatitis, baseline serum creatinine and male gender. Overall survival was not significantly different across AKI stages (range 53-65%). In patients with no AKI worsening, 90-day survival was consistently better when AKI improved independent of HRS reversal, regardless of the initial AKI stage, with patients with Stage 1 at initial diagnosis achieving the greatest clinical benefit. A significant association was observed between AKI reduction and overall 90-day survival (P = 0.0022). CONCLUSIONS: A reduction in AKI stage, independent of HRS reversal, was sufficient to improve overall survival in patients with HRS-1. The goal for HRS-1 treatment should be less stringent than absolute HRS reversal.


Assuntos
Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/patologia , Síndrome Hepatorrenal/mortalidade , Terlipressina/uso terapêutico , Vasoconstritores/uso terapêutico , Injúria Renal Aguda/prevenção & controle , Idoso , Método Duplo-Cego , Feminino , Síndrome Hepatorrenal/tratamento farmacológico , Síndrome Hepatorrenal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
3.
Clin Gastroenterol Hepatol ; 15(2): 266-272.e1, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27464593

RESUMO

BACKGROUND & AIMS: Patients with systemic inflammatory response syndrome (SIRS) along with decompensated cirrhosis and renal dysfunction have a poor prognosis and a lower response to treatment. We evaluated the effect of SIRS on the response of hepatorenal syndrome type 1 (HRS-1) to terlipressin. METHODS: We performed a retrospective study of data from a trial of the effects of terlipressin (1 mg every 6 hours or placebo with concomitant albumin) in 198 patients with HRS-1, performed at 50 investigational sites in the United States and 2 in Canada from October 2010 through February 2013. We identified patients with 2 or more criteria for SIRS, without untreated infections (28 received terlipressin and 30 received placebo), and patients with less than 2 criteria for SIRS (control subjects). Primary endpoints included HRS reversal (a decrease in serum level of creatinine to ≤1.5 mg/dL), confirmed HRS reversal (defined as 2 serum creatinine levels ≤1.5 mg/dL, ≥ 48 hours apart), and survival for 90 days after treatment. RESULTS: Baseline characteristics were similar between groups, apart from slightly higher white blood cell counts and heart rates, and slightly lower serum levels of bicarbonate in patients with SIRS versus without SIRS. HRS was reversed in 42.9% of patients who received terlipressin with SIRS (12/28) versus 6.7% of patients who received placebo (2/30) (P = .0018); confirmed HRS reversal occurred in 32.1% of patients who received terlipressin with SIRS (9/28) versus 3.3% who received placebo (1/30) (P = .0048). A larger proportion of patients with SIRS who received terlipressin survived for 90 days without a transplant (13/28; 46.4%) than patients with SIRS who received placebo (7/30; 23.3%) (P = .076). CONCLUSIONS: In an analysis of data from a placebo-controlled study, we found that terlipressin improved renal function and reversed HRS in a higher proportion of patients with HRS-1 and SIRS than patients who received albumin plus placebo. ClincialTrials.gov, number NCT 01143246.


Assuntos
Síndrome Hepatorrenal/tratamento farmacológico , Lipressina/análogos & derivados , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Vasoconstritores/uso terapêutico , Idoso , Canadá , Feminino , Síndrome Hepatorrenal/complicações , Humanos , Lipressina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Estudos Retrospectivos , Análise de Sobrevida , Síndrome de Resposta Inflamatória Sistêmica/complicações , Terlipressina , Resultado do Tratamento , Estados Unidos
4.
Gastroenterology ; 150(7): 1579-1589.e2, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26896734

RESUMO

BACKGROUND & AIMS: Hepatorenal syndrome type 1 (HRS-1) in patients with cirrhosis and ascites is a functional, potentially reversible, form of acute kidney injury characterized by rapid (<2 wk) and progressive deterioration of renal function. Terlipressin is a synthetic vasopressin analogue that acts, via vascular vasopressin V1 receptors, as a systemic vasoconstrictor. We performed a phase 3 study to evaluate the efficacy and safety of intravenous terlipressin plus albumin vs placebo plus albumin in patients with HRS-1. METHODS: Adult patients with cirrhosis, ascites, and HRS-1 (based on the 2007 International Club of Ascites criteria of rapidly deteriorating renal function) were assigned randomly to groups given intravenous terlipressin (1 mg, n = 97) or placebo (n = 99) every 6 hours with concomitant albumin. Treatment continued through day 14 unless the following occurred: confirmed HRS reversal (CHRSR, defined as 2 serum creatinine [SCr] values ≤1.5 mg/dL, at least 40 hours apart, on treatment without renal replacement therapy or liver transplantation) or SCr at or above baseline on day 4. The primary end point was the percentage of patients with confirmed CHRSR. Secondary end points included the incidence of HRS reversal (defined as at least 1 SCr value ≤1.5 mg/dL while on treatment), transplant-free survival, and overall survival. The study was performed at 50 investigational sites in the United States and 2 in Canada, from October 2010 through February 2013. RESULTS: Baseline demographic/clinical characteristics were similar between groups. CHRSR was observed in 19 of 97 patients (19.6%) receiving terlipressin vs 13 of 99 patients (13.1%) receiving placebo (P = .22). HRS reversal was achieved in 23 of 97 (23.7%) patients receiving terlipressin vs 15 of 99 (15.2%) receiving placebo (P = .13). SCr decreased by 1.1 mg/dL in patients receiving terlipressin and by only 0.6 mg/dL in patients receiving placebo (P < .001). Decreases in SCr and survival were correlated (r(2) = .882; P < .001). Transplant-free and overall survival were similar between groups. A significantly greater proportion of patients with CHRSR who received terlipressin survived until day 90 than patients who did not have CHRSR after receiving terlipressin (P < .001); this difference was not observed in patients who did vs did not have CHRSR after receiving placebo (P = .28). There were similar numbers of adverse events in each group, but patients in the terlipressin group had more ischemic events. CONCLUSIONS: Terlipressin plus albumin was associated with greater improvement in renal function vs albumin alone in patients with cirrhosis and HRS-1. Patients had similar rates of HRS reversal with terlipressin as they did with albumin. ClinicalTrials.gov no: NCT01143246.


Assuntos
Albuminas/administração & dosagem , Síndrome Hepatorrenal/tratamento farmacológico , Cirrose Hepática/complicações , Lipressina/análogos & derivados , Vasoconstritores/administração & dosagem , Adulto , Canadá , Quimioterapia Combinada , Feminino , Síndrome Hepatorrenal/etiologia , Síndrome Hepatorrenal/fisiopatologia , Humanos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Testes de Função Renal , Lipressina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terlipressina , Resultado do Tratamento
5.
Liver Int ; 35(5): 1492-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25312770

RESUMO

Hypersplenism is a common manifestation of portal hypertension in the cirrhotic. More than half of cirrhotics will have low platelet counts, but neutropenia is much less common. Despite being common in the cirrhotic population, the presence of hypersplenism is of little clinical consequence. The presence of hypersplenism suggests more advanced liver disease and an increase in risk of complications, but there is no data showing that correcting the hypersplenism improves patient survival. In most series, the most common indications for treating the hypersplenism is to increase platelet and white blood cell counts to allow for use of drugs that suppress the bone marrow such as interferon alpha and chemotherapeutic agents. There are several approaches used to treat hypersplenism. Portosystemic shunts are of questionable benefit. Splenectomy, either open or laparoscopically, is the most effective but is associated with a significant risk of portal vein thrombosis. Partial splenic artery embolization and radiofrequency ablation are effective methods for treating hypersplenism, but counts tend to fall back to baseline long-term. Pharmacological agents are also effective in increasing platelet counts. Development of direct acting antivirals against hepatitis C will eliminate the most common indication for treatment. We lack controlled trials designed to determine if treating the hypersplenism has benefits other than raising the platelet and white blood cell counts. In the absence of such studies, hypersplenism in most patients should be considered a laboratory abnormality and not treated, in other words forget it.


Assuntos
Hiperesplenismo/terapia , Hipertensão Portal/fisiopatologia , Cirrose Hepática/complicações , Esplenomegalia/terapia , Ablação por Cateter , Embolização Terapêutica , Humanos , Hiperesplenismo/sangue , Laparoscopia , Contagem de Leucócitos , Contagem de Plaquetas , Veia Porta/patologia , Esplenectomia , Esplenomegalia/sangue , Resultado do Tratamento , Trombose Venosa/patologia
6.
Hepatology ; 53(5): 1600-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21520173

RESUMO

UNLABELLED: Some patients with liver disease progress to cirrhosis, but the risk factors for cirrhosis development are unknown. Dyskeratosis congenita, an inherited bone marrow failure syndrome associated with mucocutaneous anomalies, pulmonary fibrosis, and cirrhosis, is caused by germline mutations of genes in the telomerase complex. We examined whether telomerase mutations also occurred in sporadic cirrhosis. In all, 134 patients with cirrhosis of common etiologies treated at the Liver Research Institute, University of Arizona, between May 2008 and July 2009, and 528 healthy subjects were screened for variation in the TERT and TERC genes by direct sequencing; an additional 1,472 controls were examined for the most common genetic variation observed in patients. Telomere length of leukocytes was measured by quantitative polymerase chain reaction. Functional effects of genetic changes were assessed by transfection of mutation-containing vectors into telomerase-deficient cell lines, and telomerase activity was measured in cell lysates. Nine of the 134 patients with cirrhosis (7%) carried a missense variant in TERT, resulting in a cumulative carrier frequency significantly higher than in controls (P = 0.0009). One patient was homozygous and eight were heterozygous. The allele frequency for the most common missense TERT variant was significantly higher in patients with cirrhosis (2.6%) than in 2,000 controls (0.7%; P = 0.0011). One additional patient carried a TERC mutation. The mean telomere length of leukocytes in patients with cirrhosis, including six mutant cases, was shorter than in age-matched controls (P = 0.0004). CONCLUSION: Most TERT gene variants reduced telomerase enzymatic activity in vitro. Loss-of-function telomerase gene variants associated with short telomeres are risk factors for sporadic cirrhosis.


Assuntos
Cirrose Hepática/genética , Mutação de Sentido Incorreto , Telomerase/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
7.
J Hepatol ; 55(2): 315-21, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21167235

RESUMO

BACKGROUND & AIMS: Administration of terlipressin plus albumin is effective in reversing type 1 HRS as compared to albumin alone. However, only about 1/3 of patients respond to treatment, therefore, predictors of response and survival would help identify the patients most likely to benefit from treatment. METHODS: We analyzed our controlled trial of terlipressin vs. placebo (Gastroenterology 2008;134:1360) to define factors predictive of a response and to correlate hemodynamic changes to changes in renal function. RESULTS: Single variant analysis showed treatment with terlipressin, MELD score, and baseline serum creatinine to be predictive of HRS reversal. Alcoholic hepatitis, baseline serum creatinine, and MELD score were predictive of survival. When treatment was not considered as a variable, only baseline serum creatinine predicted HRS reversal. Baseline serum creatinine, presence of alcoholic hepatitis, and Child-Pugh score were also predictive of survival on multivariate analysis. The rise in mean arterial pressure (MAP) following terlipressin administration was not predictive of HRS reversal. However, in those who achieved HRS reversal from terlipressin, there was a significant rise in MAP from beginning to end of treatment. CONCLUSIONS: The most consistent predictor of response to terlipressin and of survival is the baseline serum creatinine. Patients most likely to benefit from terlipressin have earlier onset renal failure (i.e. serum creatinine <5.0mg/dl). A sustained rise in MAP is required for HRS reversal. As MAP is a surrogate marker for the hyperdynamic circulation, it is only with improvement in the hyperdynamic circulation that HRS reversal is observed.


Assuntos
Albuminas/administração & dosagem , Creatinina/sangue , Síndrome Hepatorrenal/tratamento farmacológico , Lipressina/análogos & derivados , Adulto , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Hemodinâmica/efeitos dos fármacos , Síndrome Hepatorrenal/sangue , Síndrome Hepatorrenal/classificação , Síndrome Hepatorrenal/fisiopatologia , Humanos , Lipressina/administração & dosagem , Masculino , Estudos Prospectivos , Terlipressina , Vasoconstritores/administração & dosagem
8.
Liver Transpl ; 17(11): 1328-32, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21837734

RESUMO

The development of hepatorenal syndrome type 1 (HRS1) is associated with a poor prognosis. Liver transplantation improves this prognosis, but the degree of the improvement is unclear. Most patients receive vasoconstrictors such as terlipressin before transplantation, and this may affect the posttransplant outcomes. We examined a cohort of patients with access to liver transplantation from our previously published study of terlipressin plus albumin versus albumin alone in the treatment of HRS1. The purpose of this analysis was the quantification of the survival benefits of liver transplantation for patients with HRS1. Ninety-nine patients were randomized to terlipressin or placebo. Thirty-five patients (35%) received a liver transplant. Among those receiving terlipressin plus albumin, the 180-day survival rates were 100% for transplant patients and 34% for nontransplant patients; among those receiving only albumin, the rates were 94% for transplant patients and 17% for nontransplant patients. The survival rate was significantly better for those achieving a reversal of hepatorenal syndrome (HRS) versus those not achieving a reversal (47% versus 4%, P < 0.001), but it was significantly lower for the responders versus those undergoing liver transplantation (97%). We conclude that the use of terlipressin plus albumin has no significant impact on posttransplant survival. Liver transplantation offers a clear survival benefit to HRS1 patients regardless of the therapy that they receive or the success or failure of HRS reversal. The most likely benefit of terlipressin in patients undergoing liver transplantation for HRS1 is improved pretransplant renal function, and this should make the posttransplant management of this difficult group of patients easier. For patients not undergoing transplantation, HRS reversal with terlipressin and/or albumin improves survival.


Assuntos
Síndrome Hepatorrenal/mortalidade , Síndrome Hepatorrenal/cirurgia , Falência Hepática/mortalidade , Falência Hepática/cirurgia , Transplante de Fígado/mortalidade , Albuminas/uso terapêutico , Estudos de Coortes , Síndrome Hepatorrenal/tratamento farmacológico , Humanos , Falência Hepática/tratamento farmacológico , Lipressina/análogos & derivados , Lipressina/uso terapêutico , Prognóstico , Taxa de Sobrevida , Terlipressina , Vasoconstritores/uso terapêutico
9.
Curr Gastroenterol Rep ; 13(1): 17-25, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21080246

RESUMO

One of the most common manifestations of the development of portal hypertension in the patient with cirrhosis is the appearance of ascites. Once ascites develops, the prognosis worsens and the patient becomes susceptible to complications such as bacterial peritonitis, hepatic hydrothorax, hyponatremia, and complications of diuretic therapy. As the liver disease progresses, the ascites becomes more difficult to treat and many patients develop renal failure. Most patients can be managed by diuretics which, when used correctly, will control the ascites. Spontaneous bacterial peritonitis can be treated effectively, but portends a worse prognosis. Once the ascites becomes refractory to diuretics, liver transplantation is the best option, although use of transjugular intrahepatic portosystemic shunts will control the ascites in many patients. Lastly, the development of hepatorenal syndrome indicates the patient's liver disease is advanced, and transplantation again is the best option. However, use of vasoconstrictors may improve renal function in some patients, helping in their management while they await a liver transplant.


Assuntos
Ascite/terapia , Síndrome Hepatorrenal/terapia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Ascite/complicações , Ascite/fisiopatologia , Diagnóstico Diferencial , Diuréticos/uso terapêutico , Síndrome Hepatorrenal/diagnóstico , Síndrome Hepatorrenal/etiologia , Síndrome Hepatorrenal/prevenção & controle , Humanos , Hidrotórax/etiologia , Hidrotórax/terapia , Hipertensão Portal/fisiopatologia , Hiponatremia/etiologia , Hiponatremia/terapia , Cirrose Hepática/fisiopatologia , Transplante de Fígado , Infecções Oportunistas/complicações , Peritonite/complicações , Peritonite/tratamento farmacológico , Derivação Portossistêmica Transjugular Intra-Hepática , Prognóstico , Terapia de Substituição Renal , Vasoconstritores/uso terapêutico
14.
Am J Gastroenterol ; 103(7): 1698-706, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18494835

RESUMO

OBJECTIVE: We investigated patterns of use of alcohol and its clinical effects among cirrhotic subjects who participated in a randomized clinical trial comparing the efficacy of transjugular intravenous portosystemic shunt and distal splenorenal shunt. METHODS: There were 132 cirrhotic subjects, 78 with alcoholic liver disease (ALD), who were followed for a median of 49 months (range 2-93 months). Alcohol use was assessed by patient questionnaire, with corroboration by family members. RESULTS: Twenty-eight subjects (21%) were drinking at study entry and 60 subjects (45%) drank during follow-up. Heavy drinking (>4 drinks/day) was recorded in 25 ALD subjects, but in no non-ALD subjects (P < 0.0001). Drinking by ALD subjects was associated with a 153% increase in gamma-glutamyl transpeptidase (GGT) (P < 0.0001). The frequencies of death (46%vs 30%), ascites (33%vs 20%), encephalopathy (56%vs 42%), and variceal bleeding (11%vs 3%) were greater in the ALD group. In a Cox proportional hazards model only "ever heavy drinking" was associated with death (P= 0.0099), while recent heavy drinking increased the hazard of variceal hemorrhage dramatically (odds ratio 10.85). CONCLUSIONS: Whereas most cirrhotic subjects, alcoholic or not, did not drink during 5 yr of observation, heavy alcohol use occurred exclusively in ALD patients. Alcohol use by ALD subjects was associated with elevations in GGT and was linked to death and with rebleeding from shunt dysfunction.


Assuntos
Consumo de Bebidas Alcoólicas , Cirrose Hepática Alcoólica/fisiopatologia , Consumo de Bebidas Alcoólicas/mortalidade , Ascite/etiologia , Varizes Esofágicas e Gástricas/complicações , Feminino , Seguimentos , Hemorragia Gastrointestinal/complicações , Encefalopatia Hepática/etiologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/enzimologia , Cirrose Hepática/mortalidade , Cirrose Hepática/fisiopatologia , Cirrose Hepática Alcoólica/enzimologia , Cirrose Hepática Alcoólica/mortalidade , Hepatopatias Alcoólicas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , gama-Glutamiltransferase/sangue
15.
Curr Gastroenterol Rep ; 10(1): 30-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18417040

RESUMO

Transjugular intrahepatic portosystemic shunt (TIPS) is a commonly used approach for managing many complications of portal hypertension. It is an attractive option due to its relative ease of creation (> 90% success rate) and the availability at most hospitals of an interventional radiologist capable of performing the procedure. TIPS is the preferred approach to control acutely bleeding esophageal or gastric varices that cannot be controlled with medical management. It is also now preferred to surgical shunts for preventing rebleeding in patients who rebleed despite adequate medical management. TIPS is more effective than large-volume paracentesis in controlling refractory cirrhotic ascites, with possibly a slight survival benefit but also increased encephalopathy. TIPS should be used to control refractory ascites in patients who cannot be managed with large-volume paracentesis. The role of TIPS in the treatment of hepatorenal syndrome is unclear; currently only patients with type 2 hepatorenal syndrome should be considered candidates for TIPS.


Assuntos
Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos
16.
Biochem J ; 394(Pt 2): 519-26, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16279867

RESUMO

The transcription rate and protein expression from both GSTA2 (glutathione S-transferase A2) and albumin genes decrease in rat liver after IL-6 (interleukin 6) plus DEX (dexamethasone) treatment of primary hepatocytes or after LPS (lipopolysaccharide)-induced acute-phase response in animals. The down-regulation is associated with the induced expression of a nuclear protein (termed IL6DEX-NP for IL-6/DEX-induced nuclear protein) that binds to a specific site on the promoter of GSTA2, leading to a decrease in transcriptional activity. IL6DEX-NP is not similar to other transcription factors, and, for identification, we functionally cloned it from a rat liver library using a yeast one-hybrid screen based on DNA-binding activity. The cloned sequence was a truncated form of USP3 (ubiquitin-specific protease 3) and the truncated USP3 protein in a yeast extract bound to DNA containing the IL6DEX-NP recognition sequence. Using 5'- and 3'-RACE (rapid amplification of cDNA ends), the complete sequence of USP3 was found in liver from LPS-treated rats. However, using Western blot analysis, only truncated forms of USP3 could be identified in nuclear extracts from LPS-treated rat livers. A GSTA2 promoter-reporter gene plasmid and USP3-expressing plasmids were transfected into rat hepatoma cells. Expression of the short form of USP3, but not the full-length protein, abolished expression from the reporter gene. Chromatin immunoprecipitation localized USP3 to the GSTA2 promoter in rat hepatocytes in vivo. We believe that the short form of USP3 is IL6DEX-NP and that it may play an important role in the negative regulation of proteins during the acute-phase response.


Assuntos
Endopeptidases/química , Endopeptidases/metabolismo , Regulação Enzimológica da Expressão Gênica , Glutationa Transferase/genética , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Clonagem Molecular , DNA/genética , DNA/metabolismo , Endopeptidases/genética , Biblioteca Gênica , Fígado/metabolismo , Dados de Sequência Molecular , Peso Molecular , Ligação Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratos , Proteínas Repressoras/química , Proteínas Repressoras/genética , Transfecção , Proteases Específicas de Ubiquitina
19.
Biochem J ; 386(Pt 3): 525-33, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15471539

RESUMO

GSTP1 (glutathione S-transferase pi) is involved in stress responses and in cellular proliferation pathways as an inhibitor of JNK (c-Jun N-terminal kinase). It has been proposed that monomeric GSTP1 functions as a JNK inhibitor. All of the studies to date have been performed using rodent cells, and it is unclear if monomeric GSTP1 exists in human cells. Monomeric GSTP1 was sought in human gastric cancer cells (Kato III) and in normal human erythrocytes using gel filtration, ELISA and Western blots. Monomeric GSTP1 was found in conditioned medium, in cytosol of Kato III cells and in cytosol of erythrocytes. GSTP1 subunits from Kato III cells and erythrocytes were heterogeneous when analysed by MALDI-TOF (matrix-assisted laser-desorption ionization-time-of-flight) MS, suggesting that there were post-translational modifications to GSTP1. One post-translational modification, phosphorylation of a serine residue in the C-terminal portion of GSTP1 where JNK binds, was identified in GSTP1 purified from Kato III cells, but not in GSTP1 purified from human erythrocytes. Therefore normal and malignant human cells contain GSTP1 monomers with post-translational modifications, and it is likely that GSTP1 monomers regulate JNK activity in human cells in the same manner as in rodent cells.


Assuntos
Eritrócitos/enzimologia , Glutationa Transferase/química , Glutationa Transferase/metabolismo , Isoenzimas/química , Isoenzimas/metabolismo , Neoplasias Gástricas/enzimologia , Animais , Western Blotting , Linhagem Celular Tumoral , Cromatografia em Gel , Meios de Cultivo Condicionados/química , Citosol/enzimologia , Dimerização , Ensaio de Imunoadsorção Enzimática , Glutationa S-Transferase pi , Glutationa Transferase/isolamento & purificação , Humanos , Isoenzimas/isolamento & purificação , Espectrometria de Massas , Fosforilação , Processamento de Proteína Pós-Traducional , Estrutura Quaternária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/isolamento & purificação , Subunidades Proteicas/metabolismo , Roedores , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
Biochem J ; 377(Pt 3): 763-8, 2004 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-14561216

RESUMO

The acute phase response is characterized by positive and negative regulation of many liver proteins including GSTs (glutathione S-transferases) and albumin. The expression of albumin and some GSTs are dependent on HNF1 (hepatic nuclear factor 1). Interleukin 6 plus dexamethasone induce a nuclear protein (IL6DEX-NP) in rat hepatocytes in vitro that binds to a promoter element adjacent to the HNF1 site of rGSTA2 and decreases its expression. We determined how HNF1 and IL6DEX-NP regulate rGSTA2 and albumin expression in rats during the acute phase response after LPS (lipopolysaccharide) treatment. Expression of rGSTA2 and albumin mRNA decreased 3 h after LPS treatment and remained low for 48 h. Transcription rates showed a similar pattern but albumin transcription was less affected. HNF1 and IL6DEX-NP binding to the rGSTA2 promoter was present in control livers but was absent at 3 and 6 h after LPS. By 12 h, HNF1 and IL6DEX-NP binding to the rGSTA2 promoter reappeared and increased to above normal at 48 h. The patterns of HNF1 and IL6DEX-NP binding to the albumin promoter were similar. Affinity of IL6DEX-NP for the albumin promoter was less than that for the rGSTA2 promoter and changes in the transcription rates were consistent with the difference. Early decreases in rGSTA2 and albumin during the acute phase response are due to decreased binding of HNF1. Later persistent decreases in transcriptional rate of rGSTA2 and to a lesser extent albumin are due to increased IL6DEX-NP binding. IL6DEX-NP appears to be an important negative regulator of gene expression in vitro and in vivo.


Assuntos
Reação de Fase Aguda/enzimologia , Reação de Fase Aguda/metabolismo , Albuminas/biossíntese , Proteínas de Ligação a DNA , Dexametasona/imunologia , Glutationa Transferase/biossíntese , Interleucina-6/fisiologia , Fígado/enzimologia , Proteínas Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Reação de Fase Aguda/genética , Reação de Fase Aguda/fisiopatologia , Albuminas/genética , Animais , Sítios de Ligação/genética , Glutationa Transferase/genética , Fator 1 Nuclear de Hepatócito , Fator 1-alfa Nuclear de Hepatócito , Fator 1-beta Nuclear de Hepatócito , Hepatócitos/química , Lipopolissacarídeos/farmacologia , Fígado/fisiopatologia , Masculino , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos
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