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1.
Cell Mol Life Sci ; 77(9): 1811-1825, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31363815

RESUMO

Premature intrapancreatic trypsinogen activation is widely regarded as an initiating event for acute pancreatitis. Previous studies have alternatively implicated secretory vesicles, endosomes, lysosomes, or autophagosomes/autophagolysosomes as the primary site of trypsinogen activation, from which a cell-damaging proteolytic cascade originates. To identify the subcellular compartment of initial trypsinogen activation we performed a time-resolution analysis of the first 12 h of caerulein-induced pancreatitis in transgenic light chain 3 (LC3)-GFP autophagy reporter mice. Intrapancreatic trypsin activity increased within 60 min and serum amylase within 2 h, but fluorescent autophagosome formation only by 4 h of pancreatitis in parallel with a shift from cytosolic LC3-I to membranous LC3-II on Western blots. At 60 min, activated trypsin in heavier subcellular fractions was co-distributed with cathepsin B, but not with the autophagy markers LC3 or autophagy protein 16 (ATG16). Supramaximal caerulein stimulation of primary pancreatic acini derived from LC3-GFP mice revealed that trypsinogen activation is independent of autophagolysosome formation already during the first 15 min of exposure to caerulein. Co-localization studies (with GFP-LC3 autophagosomes versus Ile-Pro-Arg-AMC trypsin activity and immunogold-labelling of lysosomal-associated membrane protein 2 [LAMP-2] versus trypsinogen activation peptide [TAP]) indicated active trypsin in autophagolysosomes only at the later timepoints. In conclusion, during the initiating phase of caerulein-induced pancreatitis, premature protease activation develops independently of autophagolysosome formation and in vesicles arising from the secretory pathway. However, autophagy is likely to regulate overall intracellular trypsin activity during the later stages of this disease.


Assuntos
Autofagia , Ceruletídeo/toxicidade , Pancreatite/patologia , Tripsina/metabolismo , Tripsinogênio/metabolismo , Animais , Autofagossomos/metabolismo , Endossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pancreatite/induzido quimicamente , Pancreatite/metabolismo , Vesículas Secretórias/metabolismo
2.
J Biol Chem ; 294(2): 697-707, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30455353

RESUMO

Acute pancreatitis is characterized by premature intracellular protease activation and infiltration of inflammatory cells, mainly neutrophil granulocytes and macrophages, into the organ. The lysosomal proteases cathepsin B, D, and L have been identified as regulators of early zymogen activation and thus modulators of the severity of pancreatitis. Cathepsin C (CTSC, syn. dipeptidly-peptidase I) is a widely expressed, exo-cystein-protease involved in the proteolytic processing of various other lysosomal enzymes. We have studied its role in pancreatitis. We used CTSC-deleted mice and their WT littermates in two experimental models of pancreatitis. The mild model involved eight hourly caerulein injections and the severe model partial duct ligation. Isolated pancreatic acini and spleen-derived leukocytes were used for ex vivo experiments. CTSC is expressed in the pancreas and in inflammatory cells. CTSC deletion reduced the severity of pancreatitis (more prominently in the milder model) without directly affecting intra-acinar cell trypsin activation in vitro The absence of CTSC reduced infiltration of neutrophil granulocytes impaired their capacity for cleaving E-cadherin in adherens junctions between acinar cells and reduced the activity of neutrophil serine proteases polymorphonuclear (neutrophil) elastase, cathepsin G, and proteinase 3, but not neutrophil motility. Macrophage invasion was not dependent on the presence of CTSC. CTSC is a regulator and activator of various lysosomal enzymes such as cathepsin B, D, and L. Its loss mitigates the severity of pancreatitis not by reducing intra-acinar cell zymogen activation but by reducing infiltration of neutrophil granulocytes into the pancreas. In this context one of its key roles is that of an activator of neutrophil elastase.


Assuntos
Caderinas/metabolismo , Catepsina C/genética , Elastase de Leucócito/metabolismo , Pancreatite/genética , Células Acinares/metabolismo , Células Acinares/patologia , Doença Aguda , Animais , Catepsina C/metabolismo , Células Cultivadas , Ativação Enzimática , Deleção de Genes , Camundongos , Pancreatite/metabolismo , Pancreatite/patologia
3.
J Biol Chem ; 293(3): 1018-1029, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29229780

RESUMO

Acute pancreatitis is a complex disorder involving both premature intracellular protease activation and inflammatory cell invasion. An initiating event is the intracellular activation of trypsinogen by cathepsin B (CTSB), which can be induced directly via G protein-coupled receptors on acinar cells or through inflammatory cells. Here, we studied CTSB regulation by another lysosomal hydrolase, cathepsin D (CTSD), using mice with a complete (CTSD-/-) or pancreas-specific conditional CTSD knockout (KO) (CTSDf/f/p48Cre/+). We induced acute pancreatitis by repeated caerulein injections and isolated acinar and bone marrow cells for ex vivo studies. Supramaximal caerulein stimulation induced subcellular redistribution of CTSD from the lysosomal to the zymogen-containing subcellular compartment of acinar cells and activation of CTSD, CTSB, and trypsinogen. Of note, the CTSD KO greatly reduced CTSB and trypsinogen activation in acinar cells, and CTSD directly activated CTSB but not trypsinogen in vitro During pancreatitis in pancreas-specific CTSDf/f/p48Cre/+ animals, markers of severity were reduced only at 1 h, whereas in the complete KO, this effect also included the late disease phase (8 h), indicating an important effect of extra-acinar CTSD on course of the disease. CTSD-/- leukocytes exhibited reduced cytokine release after lipopolysaccharide (LPS) stimulation, and CTSD KO also reduced caspase-3 activation and apoptosis in acinar cells stimulated with the intestinal hormone cholecystokinin. In summary, CTSD is expressed in pancreatic acinar and inflammatory cells, undergoes subcellular redistribution and activation during experimental pancreatitis, and regulates disease severity by potently activating CTSB. Its impact is only minimal and transient in the early, acinar cell-dependent phase of pancreatitis and much greater in the later, inflammatory cell-dependent phase of the disease.


Assuntos
Catepsina B/metabolismo , Catepsina D/metabolismo , Pancreatite/imunologia , Pancreatite/metabolismo , Células Acinares/metabolismo , Doença Aguda , Animais , Células da Medula Óssea/metabolismo , Catepsina B/genética , Catepsina D/genética , Células Cultivadas , Clostridium histolyticum/imunologia , Clostridium histolyticum/metabolismo , Colagenases/metabolismo , Modelos Animais de Doenças , Imunoprecipitação , Marcação In Situ das Extremidades Cortadas , Camundongos Endogâmicos C57BL
4.
Gut ; 67(1): 128-137, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28108468

RESUMO

OBJECTIVE: Current non-invasive diagnostic tests can distinguish between pancreatic cancer (pancreatic ductal adenocarcinoma (PDAC)) and chronic pancreatitis (CP) in only about two thirds of patients. We have searched for blood-derived metabolite biomarkers for this diagnostic purpose. DESIGN: For a case-control study in three tertiary referral centres, 914 subjects were prospectively recruited with PDAC (n=271), CP (n=282), liver cirrhosis (n=100) or healthy as well as non-pancreatic disease controls (n=261) in three consecutive studies. Metabolomic profiles of plasma and serum samples were generated from 477 metabolites identified by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. RESULTS: A biomarker signature (nine metabolites and additionally CA19-9) was identified for the differential diagnosis between PDAC and CP. The biomarker signature distinguished PDAC from CP in the training set with an area under the curve (AUC) of 0.96 (95% CI 0.93-0.98). The biomarker signature cut-off of 0.384 at 85% fixed specificity showed a sensitivity of 94.9% (95% CI 87.0%-97.0%). In the test set, an AUC of 0.94 (95% CI 0.91-0.97) and, using the same cut-off, a sensitivity of 89.9% (95% CI 81.0%-95.5%) and a specificity of 91.3% (95% CI 82.8%-96.4%) were achieved, successfully validating the biomarker signature. CONCLUSIONS: In patients with CP with an increased risk for pancreatic cancer (cumulative incidence 1.95%), the performance of this biomarker signature results in a negative predictive value of 99.9% (95% CI 99.7%-99.9%) (training set) and 99.8% (95% CI 99.6%-99.9%) (test set). In one third of our patients, the clinical use of this biomarker signature would have improved diagnosis and treatment stratification in comparison to CA19-9.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Ductal Pancreático/diagnóstico , Detecção Precoce de Câncer/métodos , Neoplasias Pancreáticas/diagnóstico , Pancreatite Crônica/diagnóstico , Adulto , Idoso , Carcinoma Ductal Pancreático/patologia , Estudos de Casos e Controles , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Sensibilidade e Especificidade
5.
Gastroenterology ; 153(6): 1544-1554.e2, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28918191

RESUMO

BACKGROUND & AIMS: The clinical course of chronic pancreatitis is unpredictable. There is no model to assess disease severity or progression or predict patient outcomes. METHODS: We performed a prospective study of 91 patients with chronic pancreatitis; data were collected from patients seen at academic centers in Europe from January 2011 through April 2014. We analyzed correlations between clinical, laboratory, and imaging data with number of hospital readmissions and in-hospital days over the next 12 months; the parameters with the highest degree of correlation were used to develop a 3-stage chronic pancreatitis prognosis score (COPPS). The predictive strength was validated in 129 independent subjects identified from 2 prospective databases. RESULTS: The mean number of hospital admissions was 1.9 (95% confidence interval [CI], 1.39-2.44) and 15.2 for hospital days (95% CI, 10.76-19.71) for the development cohort and 10.9 for the validation cohort (95% CI, 7.54-14.30) (P = .08). Based on bivariate correlations, pain (numeric rating scale), level of glycated hemoglobin A1c, level of C-reactive protein, body mass index, and platelet count were used to develop the COPPS system. The patients' median COPPS was 8.9 points (range, 5-14). The system accurately discriminated stages of disease severity (low to high): A (5-6 points), B (7-9), and C (10-15). In Pearson correlation analysis of the development cohort, the COPPS correlated with hospital admissions (0.39; P < .01) and number of hospital days (0.33; P < .01). The correlation was validated in the validation set (Pearson correlation values of 0.36 and 0.44; P < .01). COPPS did not correlate with results from the Cambridge classification system. CONCLUSIONS: We developed and validated an easy to use dynamic multivariate scoring system, similar to the Child-Pugh-Score for liver cirrhosis. The COPPS allows objective monitoring of patients with chronic pancreatitis, determining risk for readmission to hospital and potential length of hospital stay.


Assuntos
Técnicas de Apoio para a Decisão , Pancreatite Crônica/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Índice de Massa Corporal , Proteína C-Reativa/análise , Distribuição de Qui-Quadrado , Progressão da Doença , Feminino , Alemanha , Hemoglobinas Glicadas/análise , Nível de Saúde , Humanos , Tempo de Internação , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Medição da Dor , Pancreatite Crônica/sangue , Pancreatite Crônica/complicações , Pancreatite Crônica/terapia , Readmissão do Paciente , Contagem de Plaquetas , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Adulto Jovem
6.
J Biol Chem ; 291(28): 14717-31, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27226576

RESUMO

Pancreatitis is associated with premature activation of digestive proteases in the pancreas. The lysosomal hydrolase cathepsin B (CTSB) is a known activator of trypsinogen, and its deletion reduces disease severity in experimental pancreatitis. Here we studied the activation mechanism and subcellular compartment in which CTSB regulates protease activation and cellular injury. Cholecystokinin (CCK) increased the activity of CTSB, cathepsin L, trypsin, chymotrypsin, and caspase 3 in vivo and in vitro and induced redistribution of CTSB to a secretory vesicle-enriched fraction. Neither CTSB protein nor activity redistributed to the cytosol, where the CTSB inhibitors cystatin-B/C were abundantly present. Deletion of CTSB reduced and deletion of cathepsin L increased intracellular trypsin activation. CTSB deletion also abolished CCK-induced caspase 3 activation, apoptosis-inducing factor, as well as X-linked inhibitor of apoptosis protein degradation, but these depended on trypsinogen activation via CTSB. Raising the vesicular pH, but not trypsin inhibition, reduced CTSB activity. Trypsin inhibition did not affect apoptosis in hepatocytes. Deletion of CTSB affected apoptotic but not necrotic acinar cell death. In summary, CTSB in pancreatitis undergoes activation in a secretory, vesicular, and acidic compartment where it activates trypsinogen. Its deletion or inhibition regulates acinar cell apoptosis but not necrosis in two models of pancreatitis. Caspase 3-mediated apoptosis depends on intravesicular trypsinogen activation induced by CTSB, not CTSB activity directly, and this mechanism is pancreas-specific.


Assuntos
Apoptose , Catepsina B/metabolismo , Pâncreas/enzimologia , Pancreatite/patologia , Peptídeo Hidrolases/metabolismo , Animais , Catepsina B/antagonistas & inibidores , Ativação Enzimática , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pancreatite/enzimologia , Frações Subcelulares/enzimologia
7.
Dig Dis ; 34(5): 525-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27332960

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is the 4th leading cause of cancer death worldwide and compared to other malignancies its share in cancer mortality is expected to rise further. This is due to a lack of sensitive diagnostic tools that would permit earlier detection in a potentially curable stage and the very slow progress in finding effective drug treatments for pancreatic cancer. KEY MESSAGES: Aside from genetic predispositions and environmental agents, chronic pancreatitis is by far the greatest risk factor for PDAC. It also shares several etiological factors with pancreatic cancer and represents its most challenging differential diagnosis. Biomarkers that can distinguish between chronic pancreatitis and PDAC may therefore be suitable for the latter's early detection. Moreover, targeting the natural history of chronic pancreatitis would be one approach to prevent PDAC. Targeting tumor-cell signaling directly by interfering with receptor tyrosine kinases has shown some efficacy, although the results in clinical trials were less encouraging than for other cancers. Other compounds developed have targeted the formation of extracellular matrix around the tumor, the proteolytic activity in the tumor environment, histone deacetylases, hedgehog signaling and heat shock proteins, but none has yet found its way into routine patient care. Attempts to individualize treatment according to the tumor's somatic mutation profile are novel but so far impractical. CONCLUSIONS: Progress in the treatment of pancreatic cancer has been exceedingly slow and mostly dependent on improved pharmaceutical preparations or combinations of established chemotherapeutic agents. The promise of major breakthroughs implied in targeting tumor signal transduction events has so far not materialized.


Assuntos
Antineoplásicos/uso terapêutico , Detecção Precoce de Câncer/métodos , Neoplasias Pancreáticas/diagnóstico , Pancreatite Crônica/complicações , Biomarcadores Tumorais , Humanos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Medicina de Precisão/métodos , Fatores de Risco , Transdução de Sinais
8.
Pancreatology ; 15(4 Suppl): S23-31, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26149858

RESUMO

Chronic pancreatitis is a progressive inflammatory disease of the pancreas and frequently associated with immoderate alcohol consumption. Since only a small proportion of alcoholics eventually develop chronic pancreatitis genetic susceptibility factors have long been suspected to contribute to the pathogenesis of the disease. Smaller studies in ethnically defined populations have found that not only polymorphism in proteins involved in the metabolism of ethanol, such as Alcohol Dehydrogenase and Aldehyde Dehydrogenase, can confer a risk for developing chronic pancreatitis but also mutations that had previously been reported in association with idiopathic pancreatitis, such as SPINK1 mutations. In a much broader approach employing genome wide search strategies the NAPS study found that polymorphisms in the Trypsin locus (PRSS1 rs10273639), and the Claudin 2 locus (CLDN2-RIPPLY1-MORC4 locus rs7057398 and rs12688220) confer an increased risk of developing alcohol-induced pancreatitis. These results from North America have now been confirmed by a European consortium. In another genome wide approach polymorphisms in the genes encoding Fucosyltransferase 2 (FUT2) non-secretor status and blood group B were not only found in association with higher serum lipase levels in healthy volunteers but also to more than double the risk for developing alcohol-associated chronic pancreatitis. These novel genetic associations will allow to investigate the pathophysiological and biochemical basis of alcohol-induced chronic pancreatitis on a cellular level and in much more detail than previously possible.


Assuntos
Alcoolismo/complicações , Alcoolismo/genética , Predisposição Genética para Doença/genética , Pancreatite Alcoólica/genética , Alcoolismo/enzimologia , Animais , Etanol/metabolismo , Humanos , Pancreatite Alcoólica/enzimologia
10.
Pancreatology ; 13(1): 29-32, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23395566

RESUMO

BACKGROUND/AIMS: The variable number of tandem repeats (VNTR) in the last exon of the carboxyl-ester lipase (CEL) gene has been reported to associate with alcohol-induced chronic pancreatitis (ACP) in a Japanese study. Here, we have investigated the association between the number of CEL VNTR repeats and ACP or idiopathic chronic pancreatitis (ICP) in a cohort of German patients. METHODS: Patients diagnosed with ACP (n = 203) or ICP (n = 64) were genotyped using a screening method consisting of PCR followed by DNA fragment analysis. The allele frequencies of different CEL VNTR lengths were compared to the frequencies in healthy controls (n = 390). RESULTS: We observed no statistical significant associations between CEL VNTR allele frequencies and ACP or ICP. CONCLUSION: This study did not find evidence that supported an association between the common length variations of the CEL VNTR and chronic pancreatitis.


Assuntos
Alcoolismo/complicações , Lipase/genética , Pancreatite Crônica/genética , Alcoolismo/genética , Estudos de Coortes , Frequência do Gene , Alemanha , Humanos , Fatores de Risco
11.
Gastroenterology ; 138(2): 726-37, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19900452

RESUMO

BACKGROUND & AIMS: Acute pancreatitis is characterized by an activation cascade of digestive enzymes in the pancreas. The first of these, trypsinogen, can be converted to active trypsin by the peptidase cathepsin B (CTSB). We investigated whether cathepsin L (CTSL) can also process trypsinogen to active trypsin and has a role in pancreatitis. METHODS: In CTSL-deficient (Ctsl(-/-)) mice, pancreatitis was induced by injection of cerulein or infusion of taurocholate into the pancreatic duct. Human tissue, pancreatic juice, mouse pancreatitis specimens, and recombinant enzymes were studied by enzyme assay, immunoblot, N-terminal sequencing, immunocytochemistry, and electron microscopy analyses. Isolated acini from Ctsl(-/-) and Ctsb(-/-) mice were studied. RESULTS: CTSL was expressed in human and mouse pancreas, colocalized with trypsinogen in secretory vesicles and lysosomes, and secreted into pancreatic juice. Severity of pancreatitis was reduced in Ctsl(-/-) mice, whereas apoptosis and intrapancreatic trypsin activity were increased. CTSL-induced cleavage of trypsinogen occurred 3 amino acids toward the C-terminus from the CTSB activation site and resulted in a truncated, inactive form of trypsin and an elongated propeptide (trypsinogen activation peptide [TAP]). This elongated TAP was not detected by enzyme-linked immunosorbent assay (ELISA) but was effectively converted to an immunoreactive form by CTSB. Levels of TAP thus generated by CTSB were not associated with disease severity, although this is what the TAP-ELISA is used to determine in the clinic. CONCLUSIONS: CTSL inactivates trypsinogen and counteracts the ability of CTSB to form active trypsin. In mouse models of pancreatitis, absence of CTSL induces apoptosis and reduces disease severity.


Assuntos
Catepsina L/metabolismo , Pancreatite/metabolismo , Índice de Gravidade de Doença , Tripsinogênio/metabolismo , Amilases/metabolismo , Animais , Apoptose , Catepsina B/genética , Catepsina B/metabolismo , Catepsina L/genética , Ceruletídeo/efeitos adversos , Modelos Animais de Doenças , Humanos , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Camundongos , Camundongos Knockout , Pancreatite/induzido quimicamente , Pancreatite/patologia , Ácido Taurocólico/efeitos adversos , Tripsina/metabolismo
13.
Dig Dis ; 29(2): 235-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21734390

RESUMO

Chronic pancreatitis has long been thought to be mainly associated with immoderate alcohol consumption. The observation that only ∼10% of heavy drinkers develop chronic pancreatitis not only suggests that other environmental factors, such as tobacco smoke, are potent additional risk factors, but also that the genetic component of pancreatitis is more common than previously presumed. Either disease-causing or protective traits have been indentified for mutations in different trypsinogen genes, the gene for the trypsin inhibitor SPINK1, chymotrypsinogen C, and the cystic fibrosis transmembane conductance regulator (CFTR). Other factors that have been proposed to contribute to pancreatitis are obesity, diets high in animal protein and fat, as well as antioxidant deficiencies. For the development of pancreatic cancer, preexisting chronic pancreatitis, more prominently hereditary pancreatitis, is a risk factor. The data on environmental risk factors for pancreatic cancer are, with the notable exception of tobacco smoke, either sparse, unconfirmed or controversial. Obesity appears to increase the risk of pancreatic cancer in the West but not in Japan. Diets high in processed or red meat, diets low in fruits and vegetables, phytochemicals such as lycopene and flavonols, have been proposed and refuted as risk or protective factors in different trials. The best established and single most important risk factor for cancer as well as pancreatitis and the one to clearly avoid is tobacco smoke.


Assuntos
Meio Ambiente , Neoplasias Pancreáticas/epidemiologia , Pancreatite Crônica/epidemiologia , Humanos , Neoplasias Pancreáticas/complicações , Pancreatite Crônica/complicações , Fatores de Risco
15.
Am J Gastroenterol ; 105(10): 2287-92, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20461065

RESUMO

OBJECTIVES: Patients with severe acute pancreatitis (AP) typically develop vascular leak syndrome, resulting in hemoconcentration, hypotension, pulmonary edema, and renal insufficiency. Angiopoietin-1 (Ang-1) and 2 (Ang-2) are autocrine peptides that reduce or increase endothelial permeability, respectively. The aim of this study was to determine whether Ang-1 and/or Ang-2 levels are predictive biomarkers of persistent organ failure (>48 h) and prolonged hospital course. METHODS: Banked serum from 28 patients enrolled in the Severity of Acute Pancreatitis Study at the University of Pittsburgh Medical Center (UPMC) and 58 controls was analyzed for Ang-1 and Ang-2 levels. Separately, serum from 123 patients and 103 controls at Greifswald University (GU), Germany was analyzed for Ang-2 levels. Angiopoietin levels were measured by enzyme-linked immunosorbent assay. RESULTS: In all, 6 out of 28 UPMC patients (21%) and 14 out of 123 GU patients (13%) developed persistent organ failure and were classified as severe AP. Ang-2 was significantly higher on admission in patients who developed persistent organ failure compared with those who did not in UPMC (3,698 pg/ml vs. 1,001 pg/ml; P=0.001) and GU (4,945 pg/ml vs. 2,631 pg/ml; P=0.0004) cohorts. After data scaling, admission Ang-2 levels showed a receiver-operator curve of 0.81, sensitivity 90%, and specificity 67% in predicting persistent organ failure. In addition, Ang-2 levels remained significantly higher in severe AP compared with mild AP patients until day 7 (days 2-4: P<0.005; day 7: P<0.02). Ang-1 levels were not significantly different between mild and severe AP patients on admission. CONCLUSIONS: Elevated serum Ang-2 levels on admission are associated with and may be a useful biomarker of predicting persistent organ failure and ongoing endothelial cell activation in AP.


Assuntos
Angiopoietina-2/sangue , Insuficiência de Múltiplos Órgãos/sangue , Pancreatite Necrosante Aguda/sangue , Idoso , Angiopoietina-1/sangue , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Índice de Gravidade de Doença , Estados Unidos
16.
Dig Dis ; 28(2): 324-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20814206

RESUMO

In the past, chronic pancreatitis has been regarded as a fairly uniform and largely untreatable disorder that most commonly affects patients who both lack gainful employment or adequate insurance coverage and have a tendency to smoke and drink. Large clinical trials suggest that this perception is not only misguided and discriminatory but also not based on facts. We forgot that the perception of chronic liver disease was similar before World War II, and just like liver cirrhosis the fibrosis and cirrhosis of the pancreas--i.e. chronic pancreatitis--is the end result of a range of environmental, inflammatory, infectious and genetic disorders. A growing number of these have only recently been recognized as a distinct entity and several of which are becoming truly treatable. A large proportion of the risk for developing pancreatitis is conveyed by genetic risk factors, and we estimate that less than half of those have been identified so far. The same holds true for protective factors that can prevent pancreatitis, even in the face of excessive alcohol abuse. Various gene mutations and polymorphisms appear to determine an individual's susceptibility for developing pancreatic disease, for the severity of the disease, and for the disease progression. The spectrum of genotype/phenotype associations ranges from straightforward autosomal dominant traits with near-complete penetrance, as for the most common mutations in the cationic trypsinogen gene (PRSS1), to moderate risks factors without mendelian inheritance patterns, as for SPINK1 and CFTR mutations, to very subtle risk associations and disease modifiers that can only be identified in large cohort studies, as for the chymotrypsin C, calcium-sensing receptor and the anionic trypsin (PRSS2) mutations. Only a better understanding of the disease mechanisms that underlie these changes will make an individualized therapy of pancreatic disorders a realistic option.


Assuntos
Pancreatite Crônica/etiologia , Animais , Humanos , Mutação/genética , Pancreatite Crônica/enzimologia , Pancreatite Crônica/genética , Proteínas/genética
18.
Endocrinol Metab Clin North Am ; 35(2): 289-302, viii-ix, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16632093

RESUMO

A wide range of mutations and polymorphisms in genes that relate to pancreatic function seem to be involved in the development of pancreatitis. Some of these genetic alterations lead to disease phenotypes with unequivocal mendelian inheritance patterns, whereas others seem to act as modifier genes in conjunction with environ-mental or, as yet unidentified, genetic cofactors. This article reviews germline changes in the genes for trypsin, pancreatic secretory trypsin inhibitor, the cystic fibrosis conductance regulator, lipid metabolism proteins, inflammatory mediators for cytokines, and cathepsin B.


Assuntos
Mutação em Linhagem Germinativa , Pancreatite/enzimologia , Pancreatite/genética , Tripsinogênio/genética , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Catepsina B/genética , Catepsina B/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Predisposição Genética para Doença , Humanos , Mutação Puntual , Polimorfismo Genético , Tripsina , Inibidor da Tripsina Pancreática de Kazal , Tripsinogênio/fisiologia
19.
Gastroenterology ; 129(4): 1251-67, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16230078

RESUMO

BACKGROUND & AIMS: Cadherins play an important role in cell-cell contact formation at adherens junctions. During the course of acute pancreatitis, adherens junctions are known to dissociate-a requirement for the interstitial accumulation of fluid and inflammatory cells-but the underlying mechanism is unknown. METHODS: Acute pancreatitis was induced in rats by supramaximal cerulein infusion. The pancreas and lungs were either homogenized for protein analysis or fixed for morphology. Protein sequencing was used to identify proteolytic cleavage sites and freshly prepared acini for ex vivo studies with recombinant proteases. Results were confirmed in vivo by treating experimental pancreatitis animals with specific protease inhibitors. RESULTS: A 15-kilodalton smaller variant of E-cadherin was detected in the pancreas within 60 minutes of pancreatitis, was found to be the product of E-cadherin cleavage at amino acid 394 in the extracellular domain that controls cell-contact formation, and was consistent with E-cadherin cleavage by leukocyte elastase. Employing cell culture and ex vivo acini leukocyte elastase was confirmed to cleave E-cadherin at the identified position, followed by dissociation of cell contacts and the internalization of cleaved E-cadherin to the cytosol. Inhibition of leukocyte elastase in vivo prevented E-cadherin cleavage during pancreatitis and reduced leukocyte transmigration into the pancreas. CONCLUSIONS: These data provide evidence that polymorphonuclear leukocyte elastase is involved in, and required for, the dissociation of cell-cell contacts at adherens junctions, the extracellular cleavage of E-cadherin, and, ultimately, the transmigration of leukocytes into the epithelial tissue during the initial phase of experimental pancreatitis.


Assuntos
Caderinas/metabolismo , Elastase de Leucócito/metabolismo , Pancreatite/enzimologia , Doença Aguda , Animais , Caderinas/efeitos dos fármacos , Caderinas/genética , Modelos Animais de Doenças , Variação Genética , Elastase de Leucócito/antagonistas & inibidores , Masculino , Inibidores de Proteases/farmacologia , Ratos , Ratos Wistar
20.
J Biol Chem ; 277(7): 5404-10, 2002 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11719509

RESUMO

Hereditary pancreatitis has been found to be associated with germline mutations in the cationic trypsinogen (PRSS1) gene. Here we report a family with hereditary pancreatitis that carries a novel PRSS1 mutation (R122C). This mutation cannot be diagnosed with the conventional screening method using AflIII restriction enzyme digest. We therefore propose a new assay based on restriction enzyme digest with BstUI, a technique that permits detection of the novel R122C mutation in addition to the most common R122H mutation, and even in the presence of a recently reported neutral polymorphism that prevents its detection by the AflIII method. Recombinantly expressed R122C mutant human trypsinogen was found to undergo greatly reduced autoactivation and cathepsin B-induced activation, which is most likely caused by misfolding or disulfide mismatches of the mutant zymogen. The K(m) of R122C trypsin was found to be unchanged, but its k(cat) was reduced to 37% of the wild type. After correction for enterokinase activatable activity, and specifically in the absence of calcium, the R122C mutant was more resistant to autolysis than the wild type and autoactivated more rapidly at pH 8. Molecular modeling of the R122C mutant trypsin predicted an unimpaired active site but an altered stability of the calcium binding loop. This previously unknown trypsinogen mutation is associated with hereditary pancreatitis, requires a novel diagnostic screening method, and, for the first time, raises the question whether a gain or a loss of trypsin function participates in the onset of pancreatitis.


Assuntos
Mutação , Pancreatite/genética , Tripsinogênio/genética , Tripsinogênio/metabolismo , Sequência de Aminoácidos , Arginina/química , Sítios de Ligação , Cálcio/metabolismo , Cisteína/química , Desoxirribonucleases de Sítio Específico do Tipo II/farmacologia , Feminino , Humanos , Cinética , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Fosforilação , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Fatores de Tempo , Tripsina/química
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