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1.
Langenbecks Arch Surg ; 408(1): 223, 2023 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-37270454

RESUMO

PURPOSE: After the popularization of serum immunoglobulin G4 (IgG4) measurement and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in our institute, surgical resection for non-neoplastic diseases of the pancreas became less common. Although the incidence of such false-positive cases was clarified in the 10-year period after the introduction of these measures (2009-2018), these data were not compared with the 30 years before 2009 (1979-2008). This study was performed to determine the percentage of autoimmune pancreatitis (AIP) that was included during the latter period and how the numbers of false-positive cases differed between the two periods. METHODS: From 1979 to 2008, 51 patients had clinical suspicion of pancreatic carcinoma (false-positive disease). Among these 51 patients, 32 non-alcoholic patients who had tumor-forming chronic pancreatitis (TFCP) were clinically, histologically, and immunohistochemically compared with 11 patients who had TFCP during the latter 10-year period. RESULTS: Retrospective IgG4 immunostaining of false-positive TFCP revealed 14 (35.0%) cases of AIP in the former 30 years versus 5 (45.5%) in the latter 10 years. There were 40 (5.9%) cases of TFCP among 675 patients in the former 30 years and 11 (0.9%) among 1289 patients in the latter 10 years. CONCLUSIONS: When the TFCP ratio of pancreatic resections and the AIP ratio of false-positive TFCPs were compared between the two periods, the TFCP ratio was 5.9% versus 0.9% and the AIP ratio was 35.0% versus 45.5%, respectively. It can thus be speculated that IgG4 measurement and EUS-FNA are absolutely imperative for the diagnosis of TFCP.


Assuntos
Doenças Autoimunes , Pancreatite Autoimune , Neoplasias Pancreáticas , Pancreatite Crônica , Humanos , Pancreatite Autoimune/cirurgia , Pancreatite Autoimune/patologia , Estudos Retrospectivos , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/cirurgia , Pâncreas/cirurgia , Neoplasias Pancreáticas/patologia , Pancreatite Crônica/cirurgia , Imunoglobulina G
2.
Cancer Res ; 77(9): 2328-2338, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28202517

RESUMO

Tankyrase, a PARP that promotes telomere elongation and Wnt/ß-catenin signaling, has various binding partners, suggesting that it has as-yet unidentified functions. Here, we report that the tankyrase-binding protein TNKS1BP1 regulates actin cytoskeleton and cancer cell invasion, which is closely associated with cancer progression. TNKS1BP1 colocalized with actin filaments and negatively regulated cell invasion. In TNKS1BP1-depleted cells, actin filament dynamics, focal adhesion, and lamellipodia ruffling were increased with activation of the ROCK/LIMK/cofilin pathway. TNKS1BP1 bound the actin-capping protein CapZA2. TNKS1BP1 depletion dissociated CapZA2 from the cytoskeleton, leading to cofilin phosphorylation and enhanced cell invasion. Tankyrase overexpression increased cofilin phosphorylation, dissociated CapZA2 from cytoskeleton, and enhanced cell invasion in a PARP activity-dependent manner. In clinical samples of pancreatic cancer, TNKS1BP1 expression was reduced in invasive regions. We propose that the tankyrase-TNKS1BP1 axis constitutes a posttranslational modulator of cell invasion whose aberration promotes cancer malignancy. Cancer Res; 77(9); 2328-38. ©2017 AACR.


Assuntos
Citoesqueleto de Actina/genética , Invasividade Neoplásica/genética , Neoplasias Pancreáticas/genética , Proteína 1 de Ligação a Repetições Teloméricas/genética , Citoesqueleto de Actina/patologia , Fatores de Despolimerização de Actina/genética , Proteína de Capeamento de Actina CapZ/genética , Adesão Celular/genética , Linhagem Celular Tumoral , Feminino , Adesões Focais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Quinases Lim/genética , Masculino , Invasividade Neoplásica/patologia , Neoplasias Pancreáticas/patologia , Fosforilação , Poli(ADP-Ribose) Polimerase-1/genética , Proteína 1 de Ligação a Repetições Teloméricas/biossíntese , Via de Sinalização Wnt , Quinases Associadas a rho/genética
3.
Gastric Cancer ; 13(4): 267-70, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21128064

RESUMO

A 58-year-old woman was found to have a 45-mm abdominal mass adjacent to the pancreas on screening ultrasonography, and subsequent esophagogastroduodenoscopy revealed a small gastric cancer (13 mm in diameter). We initially performed endoscopic submucosal dissection (ESD), and routine histological examination of the specimen sectioned at 2-mm intervals revealed a poorly differentiated adenocarcinoma and signet ring cell carcinoma confined to the mucosa without lymphatic-vascular capillary involvement or ulceration. These findings satisfied the expanded criteria for ESD we reported recently. We next performed laparoscopic excisional biopsy of the abdominal mass, and histological examination with immunohistochemical staining revealed a metastatic lymph node (LN) resulting from the gastric cancer. Distal gastrectomy with extended lymphadenectomy was then performed and histological examination indicated no residual cancer cells or any additional LN metastases. After the above-described clinical course, further analysis was conducted because of the highly unusual nature of this case; 60 additional deep-cut sections from the resected specimen were performed, with one section showing lymphatic involvement in the mucosa on hematoxylin and eosin staining. This case suggests practical limitations in determining lymphatic involvement through routine histological examination, which may not always be able to detect LN metastasis.


Assuntos
Adenocarcinoma/secundário , Carcinoma de Células em Anel de Sinete/secundário , Mucosa Gástrica/patologia , Gastroscopia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/cirurgia , Dissecação/métodos , Feminino , Gastrectomia , Mucosa Gástrica/cirurgia , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Gástricas/cirurgia
4.
Jpn J Clin Oncol ; 40(6): 530-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20363769

RESUMO

OBJECTIVE: Resective therapeutic strategy for left-sided pancreatic adenocarcinoma is open to debate. The post-resection outcomes and factors influencing post-resection survival for adenocarcinoma of the body and tail of the pancreas were analyzed to determine the effectiveness of surgery. METHODS: A total of 73 patients with adenocarcinoma of the body or tail of the pancreas who underwent resection between 1994 and June 2007 were evaluated for overall survival. RESULTS: Multiple malignancies were present in 34 of 73 patients (47%). Overall 1-, 3- and 5-year survival rates after surgery were 79%, 34%, and 30%, respectively. Presence of symptoms, multiple cancers and level of preoperative tumor marker did not influence post-resection survival. As for tumor characteristics, tumor size, histological tumor differentiation, retroperitoneal invasion, status of residual tumor and UICC staging represented significant prognostic indicators by univariate analysis. Gemcitabine, when administered as an adjuvant settings, strongly worked for improving post-resection outcome (5-year survival rate = 51%). Factors shown to have independent prognostic significance on multivariate analysis were tumor size (<3 vs. >or=3 cm), status of residual tumor (R0 vs. R1, 2), and postoperative administration of gemcitabine. CONCLUSIONS: Appropriate patient selection and accurate surgical technique with postoperative adjuvant therapy could benefit survival of patients with carcinoma of the pancreas body and tail.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Quimioterapia Adjuvante , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Masculino , Pancreatectomia , Neoplasias Pancreáticas/patologia , Taxa de Sobrevida , Gencitabina
5.
Surg Today ; 40(3): 272-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20180084

RESUMO

A 70-year-old woman with a pelvic tumor had undergone exploratory laparoscopy at another institution, which revealed many peritoneal nodules. Immunohistochemical staining of a biopsy specimen of the peritoneal nodules was positive for KIT. Thus, a gastrointestinal stromal tumor (GIST) was diagnosed and imatinib treatment was begun. After 16 months of this treatment, the tumor size had decreased from 51 x 55 mm to 22 x 17 mm, and surgery was performed. Laparotomy revealed complete regression of the peritoneal lesions. The primary tumor was seen to arise from the small intestine and to loosely adhere to the rectum. We performed partial resection of the small intestine. Imatinib therapy was restarted 1 month postoperatively, and the patient is doing well after 12 months of follow-up. We report this case to show that there is the possibility of curative salvage surgery after long-term imatinib treatment in some patients with peritoneal metastases of a GIST.


Assuntos
Antineoplásicos/administração & dosagem , Tumores do Estroma Gastrointestinal/cirurgia , Neoplasias do Íleo/cirurgia , Neoplasias Peritoneais/tratamento farmacológico , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Idoso , Benzamidas , Feminino , Tumores do Estroma Gastrointestinal/diagnóstico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/secundário , Humanos , Neoplasias do Íleo/diagnóstico , Neoplasias do Íleo/tratamento farmacológico , Neoplasias do Íleo/patologia , Mesilato de Imatinib , Terapia Neoadjuvante , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/secundário
6.
J Med Ultrason (2001) ; 37(2): 67-74, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27277716

RESUMO

We used contrast-enhanced ultrasound using the Sonazoid microbubble contrast agent to diagnose three cases of hepatic angiomyolipoma, which is a rare benign tumor. Some characteristic findings are obtained in the early vascular phase, for example fork-like tumor vessels. However, a variety of findings are seen after the early vascular phase because of microbubbles circulating the vascular enriched tumor.

7.
Langenbecks Arch Surg ; 395(5): 589-92, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20013290

RESUMO

PURPOSE: It is imperative for prognostic improvement of pancreatic cancer that we try to diagnose carcinoma in situ (CIS) of lesions, i.e., precursors of invasive ductal carcinomas (IDCs) at an early stage, because results of treatment of patients with IDCs themselves continue to be rather unsatisfactory. MATERIALS AND RESULTS: We report here a case of a patient who received subtotal pancreatectomy for widespread and multifocal CISs of the pancreas after preoperative brushing cytology from the epithelium of dilated main pancreatic duct proved cancer-positive preoperatively. CONCLUSIONS: From our experience, we conclude that examination for CIS of the pancreas must be recommended whenever dilatation of relatively large pancreatic ducts is found by ultrasound or computed tomography. We should therefore advance to magnetic resonance cholangiopancreatography or endoscopic retrograde cholangiopancreatography and then cytological and/or pathological assessment of the pancreatic duct whenever non-continuous narrowing, localized dilatation, or other irregularities are encountered.


Assuntos
Carcinoma in Situ/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Pancreáticas/cirurgia , Idoso , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Colangiopancreatografia Retrógrada Endoscópica , Colangiopancreatografia por Ressonância Magnética , Diagnóstico Diferencial , Humanos , Masculino , Estadiamento de Neoplasias , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia
8.
Hepatogastroenterology ; 56(89): 89-93, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19453035

RESUMO

BACKGROUND/AIMS: Pancreatoduodenectomy is associated with high morbidity rates, resulting primarily from the occurrence of pancreatic fistula at pancreatojejunostomy. We transect the pancreas using a manual clamp-crushing technique to prevent postoperative pancreatic fistula (POPF) formation. The aim of this study was to clarify the usefulness of this new technique. METHODOLOGY: Fifty patients with a normal soft pancreas who underwent pancreatoduodenectomy in the last 3 years were selected. During the last stage of the classic Whipple operation, the pancreas was transected using a clamp-crushing technique under blood-flow control. The pancreas parenchyma was crushed using forceps, and small pancreatic branch ducts were securely ligated and cut. The main pancreatic duct was identified, and pancreatojejunal reconstruction was done end-to-side with a duct-to-mucosa anastomosis, following approximation of the pancreatic stump to the jejunal wall using the one-layer suture technique. RESULTS: According to ISGPF (please use the first abbreviation for subtotal stomach--preserving pancreaticoduodenectomy) grading, POPF Grade B occurred in 10 (20%) patients. There were no Grade C patients, no postoperative hemorrhage and no POPF associated mortality. CONCLUSION: The clamp-crushing technique appears to be a safe method for pancreatic transection that is feasible in cases with a normal soft pancreas.


Assuntos
Pâncreas/cirurgia , Pancreaticoduodenectomia/métodos , Anastomose Cirúrgica , Feminino , Técnicas Hemostáticas/instrumentação , Humanos , Ligadura , Masculino , Fístula Pancreática/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Instrumentos Cirúrgicos , Resultado do Tratamento
9.
Liver Transpl ; 14(12): 1737-44, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19025917

RESUMO

This study investigated the effects of dual endothelin (ET) receptor blockade in rat models of liver ischemia and reperfusion injury (IRI). Three models of IRI were used: (1) in vivo total hepatic warm ischemia with portal shunting for 60 minutes with control (saline) and treatment groups (15 mg/kg tezosentan intravenously prior to reperfusion), (2) ex vivo hepatic perfusion after 24 hours of cold storage in University of Wisconsin solution with control and treatment groups (10 mg/kg tezosentan in the perfusate), and (3) syngeneic liver transplantation (LT) after 24 hours of cold storage in University of Wisconsin solution with control and treatment groups (10 mg/kg tezosentan intravenously prior to reperfusion). Tezosentan treatment significantly improved serum transaminase and histology after IRI in all 3 models. This correlated with reduced vascular resistance, improved bile production, and an improved oxygen extraction ratio. Treatment led to a reduction in neutrophil infiltration and interleukin-1 beta and macrophage inflammatory protein 2 production. A reduction in endothelial cell injury as measured by purine nucleoside phosphorylase was seen. Survival after LT was significantly increased with tezosentan treatment (90% versus 50%). In conclusion, this is the first investigation to examine dual receptor ET blockade in 3 models of hepatic IRI and the first to use the parenterally administered agent tezosentan. The results demonstrate that in both warm and cold IRI tezosentan administration improves sinusoidal hemodynamics and is associated with improved tissue oxygenation and reduced endothelial cell damage. In addition, reduced tissue inflammation, injury, and leukocyte chemotactic signaling were seen. These results provide compelling data for the further investigation of the use of tezosentan in hepatic IRI.


Assuntos
Antagonistas dos Receptores de Endotelina , Transplante de Fígado , Fígado/irrigação sanguínea , Fígado/fisiopatologia , Piridinas/farmacologia , Traumatismo por Reperfusão/fisiopatologia , Tetrazóis/farmacologia , Animais , Modelos Animais de Doenças , Hemodinâmica/efeitos dos fármacos , Isquemia/metabolismo , Isquemia/patologia , Fígado/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Isquemia Quente
10.
Liver Transpl ; 13(3): 361-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17318854

RESUMO

This study examined the efficacy of the caspase inhibitor, IDN-6556, in a rat model of liver ischemia-reperfusion injury. Livers from male Sprague-Dawley rats were reperfused for 120 minutes after 24 hours of 4 degrees C cold storage in University of Wisconsin solution. Portal blood flow measurements estimated sinusoidal resistance, and bile production, alanine aminotransferase activities, and Suzuki scores were evaluated as parameters of hepatocyte/liver injury. Treated livers were exposed to 25 or 50 microM of IDN-6556 in University of Wisconsin storage solution and/or the perfusate. All treatment regimens with IDN-6556 significantly improved portal blood flow measured at 120 minutes, and significant improvements were seen as early as 30 minutes when inhibitor was also present in the perfusate (P < 0.01). All treatment groups with IDN-6556 significantly increased bile production by 3-4-fold compared with controls (P < 0.01), and reductions in alanine aminotransferase activities were seen within 90 minutes of reperfusion (P < 0.05). These data were confirmed by improved Suzuki scores (less sinusoidal congestion, necrosis, and vacuolization) in all treated groups. Livers from the IDN-6556-treated groups had markedly reduced caspase activities and TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling)-positive cells, suggesting reductions in apoptosis. IDN-6556 present in cold storage media ameliorated liver injury due to cold ischemia and reperfusion injury and may be a rational therapeutic approach to reduce the risk of liver ischemia in the clinical setting.


Assuntos
Inibidores de Caspase , Inibidores Enzimáticos/farmacologia , Ácidos Pentanoicos/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Temperatura , Animais , Apoptose/efeitos dos fármacos , Masculino , Modelos Animais , Preservação de Órgãos/métodos , Soluções para Preservação de Órgãos/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Resultado do Tratamento
11.
Transplantation ; 75(8): 1118-23, 2003 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-12717188

RESUMO

BACKGROUND: Ischemia-reperfusion (I/R) injury is a prime inflammatory factor in the dysfunction of orthotopic liver transplants. Interleukin (IL)-13 suppresses macrophage production of proinflammatory mediators. This study explores the effects of adenovirus (Ad)-based IL-13 gene transfer in rat models of hepatic I/R injury. METHODS: The authors used a model of warm in situ ischemia followed by reperfusion, and ex vivo cold ischemia followed by transplantation. RESULTS: In a model of warm in situ ischemia followed by reperfusion, Ad-based IL-13 significantly diminished hepatocellular injury, assessed by serum glutamic oxaloacetic transaminase (SGOT) levels, as compared with Ad-based beta-galactosidase (gal)-treated livers. In a model of ex vivo cold ischemia followed by transplantation, the survival of liver grafts increased from 50% in Ad-beta-gal untreated controls to 100% after Ad-IL-13 gene therapy. This beneficial effect correlated with improved liver function (SGOT levels), preservation of hepatic histologic integrity and architecture (Suzuki criteria), and depression of neutrophil infiltration (myeloperoxidase assay). Ad-IL-13 diminished activation of macrophage-neutrophil-associated tumor necrosis factor-alpha, macrophage inflammatory protein-2, and endothelial-dependent E-selectin, but increased type 2 IL-4 and IL-13 expression. CONCLUSIONS: This study documents striking cytoprotective effects of virally induced IL-13 against hepatic I/R injury in two clinically relevant rat models of hepatic I/R injury. These data provide the rationale for novel therapeutic approaches to maximize the organ donor pool through the safer use of liver transplants despite prolonged periods of warm or cold ischemia, or both.


Assuntos
Interleucina-13/farmacologia , Fígado/patologia , Fígado/fisiopatologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Adenoviridae/genética , Animais , Criopreservação , Citocinas/genética , Expressão Gênica/efeitos dos fármacos , Técnicas de Transferência de Genes , Vetores Genéticos , Hepatócitos/fisiologia , Interleucina-13/genética , Fígado/efeitos dos fármacos , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
12.
J Am Soc Nephrol ; 14(3): 745-54, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12595512

RESUMO

Heme oxygenase-1 (HO-1) overexpression using gene transfer protects rat livers against ischemia/reperfusion (I/R) injury. This study evaluates the effects of Ad-HO-1 gene transfer in a rat renal isograft model. Donor LEW kidneys were perfused with Ad-HO-1, Ad-beta-gal, or PBS, stored at 4 degrees C for 24 h, and transplanted orthotopically into LEW recipients, followed by contralateral native nephrectomy. Serum creatinine, urine protein/creatinine ratios, severity of histologic changes, HO-1 mRNA/protein expression, and HO enzymatic activity were analyzed. Ad-HO-1 gene transfer conferred a survival advantage when compared with PBS- and Ad-beta-gal-treated controls, with median survival of 100, 7, and 7 d, respectively (P < 0.01). Serum creatinine levels were elevated at day 7 in all groups (range, 2.2 to 5.8 mg/dl) but recovered to 1.0 mg/dl by day 14 (P < 0.01) in Ad-HO-1 group, which was sustained thereafter. Urine protein/creatinine ratio at day 7 was elevated in both PBS and Ad-beta-gal, as compared with the Ad-HO-1 group (12.0 and 9.8 versus 5.0; P < 0.005); histologically, ATN and glomerulosclerosis was more severe in Ad-beta-gal group at all time points. Reverse transcriptase-PCR-based HO-1 gene expression was significantly increased before reperfusion (P < 0.001) and remained increased in the Ad-HO-1-treated group for 3 d after transplantation. Concomitantly, HO enzymatic activity was increased at transplantation and at 3 d posttransplant in the Ad-HO-1 group, compared with Ad-beta-gal controls (P < 0.05); tubular HO-1 expression was discernible early posttransplant in the Ad-HO-1 group alone. These findings are consistent with protective effects of HO-1 overexpression using a gene transfer approach against severe renal I/R injury, with reduced mortality and attenuation of tissue injury.


Assuntos
Sobrevivência de Enxerto/fisiologia , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase (Desciclizante)/metabolismo , Transplante de Rim , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/terapia , Adenoviridae/genética , Animais , Temperatura Baixa , Regulação Enzimológica da Expressão Gênica , Técnicas de Transferência de Genes , Heme Oxigenase-1 , Imuno-Histoquímica , Rim/enzimologia , Rim/patologia , Necrose Tubular Aguda/metabolismo , Necrose Tubular Aguda/patologia , Necrose Tubular Aguda/terapia , Masculino , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença
13.
Am J Transplant ; 2(9): 843-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12392290

RESUMO

Ischemia and reperfusion (IR) injury remains a significant problem in clinical liver transplantation. We investigated the effects of lymphocyte depletion with FTY720 in models of warm hepatic IR. Using 60-min partial warm hepatic IR, three groups of rats were studied: Sham--laparotomy alone; Control--water p.o. x 3 d before ischemia; Treatment--FTY720 p.o. x 3 d before ischemia. Animals were sacrificed for analysis at 6 h and 24 h post reperfusion. The effect of FTY720 pretreatment on survival was also studied using 150 min total hepatic IR with portojugular shunt. FTY720 treatment significantly reduced serum glutamic pyruvic transaminase and peripheral blood lymphocytes compared to controls at 6h and 24h (p < 0.0005). Histological grade was significantly improved in treated livers vs. controls (p < 0.05). CD3 immunocytochemical analysis revealed a significant reduction in T-cell infiltration in FTY720-treated livers (p < 0.0002). No difference in tissue myeloperoxidase levels was observed. Seven-day survival was significantly improved in treated rats vs. controls following total hepatic ischemia (p < 0.05). In conclusion, FTY720 ameliorates the biochemical and histological manifestations of hepatic IR by preventing T-lymphocyte infiltration and prolongs survival following a more severe ischemic insult. Myeloperoxidase data suggest this mechanism is independent of neutrophil activation. These results indicate that T lymphocytes are pivotal mediators in hepatic IR and may have important implications in liver transplantation.


Assuntos
Imunossupressores/farmacologia , Fígado/efeitos dos fármacos , Propilenoglicóis/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Linfócitos T/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Cloridrato de Fingolimode , Imuno-Histoquímica , Fígado/imunologia , Masculino , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/imunologia , Esfingosina/análogos & derivados , Linfócitos T/imunologia
14.
Transplantation ; 74(7): 905-12, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12394829

RESUMO

The heme oxygenase-1 (HO-1) system, the rate-limiting step in the conversion of heme, is among the most critical of cytoprotective mechanisms activated during cellular stress. The cytoprotection may result from the elimination of heme and the function of HO-1 downstream mediators, that is, biliverdin, carbon monoxide, and free iron. HO-1 overexpression exerts beneficial effects in a number of transplantation models, including antigen-independent ischemia/reperfusion injury, acute and chronic allograft rejection, and xenotransplantation. The HO-1 system is thought to exert four major functions: (1) antioxidant function; (2) maintenance of microcirculation; (3) modulatory function upon the cell cycle; and (4) anti-inflammatory function. The antioxidant function depends on heme degradation, oxygen consumption, biliverdin, and production of ferritin via iron accumulation. The production of carbon monoxide, which has vasodilation and antiplatelet aggregation properties, maintains tissue microcirculation and may be instrumental in antiapoptotic and cell arrest mechanisms. Heme catabolism and HO-1 overexpression exert profound direct and indirect inhibitory effects on the cascade of host inflammatory responses mediated by neutrophils, macrophages, and lymphocytes. These anti-inflammatory properties result in cytoprotection in a broad spectrum of graft injury experimental models, including ischemia/reperfusion, acute and chronic allograft, and xenotransplant rejection. Further, the multifaceted targets of HO-1-mediated cytoprotection may simultaneously benefit both local graft function and host systemic immune responses. Thus, the HO-1 system serves as a novel therapeutic concept in organ transplantation.


Assuntos
Heme Oxigenase (Desciclizante)/fisiologia , Transplante de Órgãos/fisiologia , Animais , Citoproteção , Heme/biossíntese , Heme Oxigenase (Desciclizante)/uso terapêutico , Heme Oxigenase-1 , Humanos , Proteínas de Membrana
15.
Transpl Immunol ; 9(2-4): 227-33, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12180835

RESUMO

Much interest has recently been focused on the physiological/pathological role of the heme oxygenase (HO) system, the rate-limiting step in the conversion of heme, in inflammatory events. The HO system may be instrumental in mediating a number of cytoprotective effects, because of its end products, biliverdin, carbon monoxide (CO) and ferrous free iron (Fe2+). As each of the byproducts acts dependently and/or co-operatively with each other, their in vivo effects are complex. In general, the HO system is thought to exert three major functions in ischemia/reperfusion injury: (1) anti-oxidant effects; (2) maintenance of microcirculation; and (3) modulatory effects upon the cell cycle. The anti-oxidant functions depend on heme degradation, oxygen consumption and the production of biliverdin/ferritin via iron accumulation. On the other hand, the production of CO, which has vasodilatory and anti-platelet aggregative properties, can maintain tissue microcirculation. Strikingly, CO may also be instrumental in anti-apoptotic and cell arrest mechanisms. The HO system prevents early injury in the re-perfused organ, and inhibits the function of immune reactive cells, such as neutrophils, macrophages and lymphocytes. The role of the HO system as a novel strategy to mitigate an antigen-independent ischemia/reperfusion injury has been documented in a number of transplantation models.


Assuntos
Citoproteção/fisiologia , Heme Oxigenase (Desciclizante)/fisiologia , Isquemia/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Animais , Biliverdina/fisiologia , Monóxido de Carbono/fisiologia , Indução Enzimática , Radicais Livres , Heme/metabolismo , Heme Oxigenase-1 , Humanos , Ferro/metabolismo , Proteínas de Membrana , Oxigênio/metabolismo
16.
Hepatology ; 35(4): 815-23, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11915027

RESUMO

A direct role of carbon monoxide (CO), an effector-signaling molecule during heme oxygenase-1 (HO-1) catalysis of heme, in the protection against hepatic ischemia/reperfusion (I/R) injury needs to be established. This study was designed to determine the effects and downstream mechanisms of CO on cold I/R injury in a clinically relevant isolated perfusion rat liver model. After 24 hours of cold storage, rat livers perfused ex vivo for 2 hours with blood supplemented with CO (300 parts per million) showed significantly decreased portal venous resistance and increased bile production, as compared with control livers perfused with blood devoid of CO. These beneficial effects correlated with improved liver function (serum glutamic oxaloacetic transaminase levels) and diminished histological features of hepatocyte injury (Banff's scores). The CO-mediated cytoprotective effects were nitric oxide synthase- and cyclic guanine monophosphate-independent, but p38 mitogen-activated protein kinase (MAPK)-dependent. Moreover, adjunctive use of zinc protoporphyrin, a competitive HO-1 inhibitor, has shown that exogenous CO could fully substitute for endogenous HO-1 in preventing hepatic I/R insult. This study performed in a clinically relevant ex vivo cold ischemia model is the first to provide the evidence that HO-1-mediated cytoprotection against hepatic I/R injury depends on the generation of, and can be substituted by, exogenous CO. The p38 MAPK signaling pathway represents the key downstream mechanism by which CO prevents the I/R insult. In conclusion, regimens that employ exogenous CO should be revisited, as they may have potential applications in preventing/mitigating I/R injury, and thus expanding the liver donor pool for clinical transplantation.


Assuntos
Monóxido de Carbono/farmacologia , Isquemia/prevenção & controle , Circulação Hepática/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Animais , Temperatura Baixa , GMP Cíclico/fisiologia , Ativação Enzimática/fisiologia , Heme Oxigenase (Desciclizante)/farmacologia , Heme Oxigenase-1 , Técnicas In Vitro , Isquemia/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Óxido Nítrico/fisiologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Proteínas Quinases p38 Ativadas por Mitógeno
17.
Transplantation ; 73(2): 287-92, 2002 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-11821745

RESUMO

BACKGROUND: Ischemia/reperfusion (I/R) injury is one of the most important causes of the early graft loss. We have shown that overexpression of heme oxygenase-1 (HO-1), an inducible heat shock protein 32, protects rat livers against I/R injury. We report on the cytoprotective effects of HO-1 in a rat cardiac I/R injury model, using cobalt protoporphyrin (CoPP) as HO-1 inducer and zinc protoporphyrin (ZnPP) as HO-1 inhibitor. METHODS: Three groups of Lewis rats were studied: group 1 control donors received phosphate-buffered saline 48 hr before the harvest; group 2 donors were pretreated with CoPP at -48 hr; and in group 3, donors received CoPP at -48 hr and ZnPP was given to recipients at reperfusion. Hearts were harvested, stored in University of Wisconsin solution (4 degrees C) for 24 hr, and then transplanted to syngeneic (Lewis) rats. RESULTS: Sixty percent of control grafts ceased their function in <15 min. In contrast, 80% of CoPP-pretreated grafts survived 14 days. All grafts stopped functioning within 24 hr after CoPP + ZnPP therapy. Cardiac HO-1 enzymatic activity and protein expression correlated with beneficial effects of CoPP and deleterious effects of adjunctive ZnPP treatment. Markedly less apoptotic (TUNEL+) myocyte/endothelial cells could be detected in CoPP cardiac grafts, as compared with controls. The expression of antiapoptotic (Bcl-2/Bag-1) proteins was up-regulated in the CoPP group. CONCLUSION: HO-1 overexpression provides potent protection against cold I/R injury in a stringent rat cardiac model. This effect depends, at least in part, on HO-1-mediated up-regulation of a host antiapoptotic mechanism, especially in the early postreperfusion period.


Assuntos
Apoptose , Heme Oxigenase (Desciclizante)/fisiologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Transplante de Coração , Heme Oxigenase-1 , Proteínas de Homeodomínio/análise , Masculino , Óxido Nítrico Sintase/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Protoporfirinas/farmacologia , Ratos , Ratos Endogâmicos Lew
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