Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the role of platelet-activating factor (PAF) as a priming signal for cytokine-induced neutrophil chemoattractant (CINC) expression by bronchoalveolar macrophages in acute pancreatitis. Pancreatitis was induced by four intramuscular injections of cerulein (50 micrograms/kg at 1-h intervals) in Wistar rats. The animals were injected intraperitoneally with 10 micrograms/kg of lipopolysaccharide (LPS) as a septic challenge. Pancreatitis rats were treated with a bolus intravenous injection of TCV-309 (3 or 30 micrograms/kg) 30 min before the septic challenge. Intense mononuclear cell infiltration and lung hemorrhage occurred in pancreatitis rats complicated with sepsis but were not seen in pancreatitis rats receiving a bolus TCV-309. Pancreatitis rats treated with TCV-309 had lower serum concentrations of CINC after septic challenge and lower levels of CINC messenger RNA (mRNA) in the lung, as well as fewer pulmonary infiltrates immunoreactive for CINC or Mac-1 (CD11b/CD18). In vitro CINC production in response to LPS by bronchoalveolar macrophages obtained from pancreatitis rats 6 h after the first cerulein injection, immediately before septic challenge, was enhanced but was significantly reduced in a TCV-309-sensitive manner. LPS-stimulated in vitro CINC production by naive bronchoalveolar macrophages was significantly enhanced by pretreatment with PAF. TMB-8 (an inhibitor of calcium release from endoplasmic reticulum) or W7 (calmodulin antagonist) completely abrogated the chemoattractant production by bronchoalveolar macrophages pretreated with PAF after LPS stimulation. Altered intracellular calcium, due to Ca2+ efflux from intracellular stores, may be involved in the "priming" of bronchoalveolar macrophages to release CINC after triggering with LPS during acute cerulein-induced pancreatitis. The PAF antagonist TCV-309 effectively prevented hyperactivity of bronchoalveolar macrophages and pancreatitis-associated lung injury after the septic challenge.
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PMID:Platelet-activating factor antagonist (TCV-309) attenuates the priming effects of bronchoalveolar macrophages in cerulein-induced pancreatitis rats. 1023 40

Epidermal growth factor (EGF) exhibits gastroprotective and ulcer-healing action. These observations prompted us to determine the influence of EGF on cerulein-induced pancreatitis (CIP) in the rat. Acute pancreatitis was induced by subcutaneous infusion of cerulein (10 microg/kg/h) for 5 h. Initially EGF was administrated twice at doses of 1, 5, 10 or 100 microg/kg s.c. (first injection 30 min prior to cerulein infusion, and the second injection 2.5 h after the start of cerulein infusion) and from this part of study 10 microg/kg was chosen for the next experiments. CIP led to a significant decrease in DNA synthesis and a reduction in pancreatic blood flow (PBF) by 42 and 30%, respectively, as well as a significant increase in pancreatic weight, plasma amylase concentration, plasma interleukin-1beta (IL-1beta) level and the development of the histological signs of pancreatic damage with marked edema, leukocyte infiltration and vacuolization of acinar cells. Treatment with EGF attenuated the pancreatic tissue damage in CIP as manifested by partial reversal of the drop in DNA synthesis and improvement of pancreatic histology. Moreover, EGF administration attenuated the fall in PBF and significantly reduced the cerulein-evoked increase in pancreatic weight. Also plasma amylase and IL-1beta were decreased in rats treated with EGF. We conclude that: (1) EGF exerts a protective effect against CIP, and (2) the beneficial activity of EGF in CIP seems to depend on the increase in pancreatic cell proliferation, the reduction in cytokine generation and the attenuation of the fall in PBF.
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PMID:Epidermal growth factor protects against pancreatic damage in cerulein-induced pancreatitis. 1039 25

Acute pancreatitis is a disease that has many causes. Each cause seems to affect the acinar cell in some way that results in the premature activation and retention of potent proteolytic enzymes. These activated enzymes then injure the acinar cell and cause the immediate release of cytokines and activate the complement system. Together, these molecules attract and sequester inflammatory cells, in particular neutrophils, which causes further secretion of cytokines, free radicals, and other vasoactive molecules, such as nitric oxide. We propose that the released inflammatory molecules induce local effects, such as pancreatic edema and necrosis, and systemic complications, such as hypotension, tachycardia, fever, capillary leak syndrome, and hypoxia. The cytokines released in the pancreas also stimulate apoptosis, further enhancing the cell death response in pancreatitis. Much of the current research is aimed at understanding the links between these series of events and finding agents that can modulate the cascade of events involved in pancreatitis. What is promising in this endeavor is that the response produced with pancreatitis is nearly identical with all etiologies, suggesting that therapy may not have to be specific to a particular cause. The mechanistic models of AP presented herein are supported by preliminary clinical studies that suggest that protease and cytokine inhibitors may improve the course of AP in specific clinical settings.
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PMID:Etiopathogenesis of acute pancreatitis. 1047 Mar 20

Mice deficient in either or both mouse alpha2-macroglobulin (MAM) and murinoglobulin-1 (MUG1) were generated and proved phenotypically normal under standard conditions. Acute pancreatitis was induced with a diet deficient in choline and methionine, supplemented with ethionine. The mortality was less than 25% in wild-type mice, as opposed to at least 56% in knockout mice, and was highest (70%) in MAM-/- mice, with earliest onset at 2 days. Plasma amylase and lipase levels were increased, but pancreatic tissue appeared histologically variable in individual mice. The clinical symptoms were most severe in MAM-/- mice and, surprisingly, were not aggravated in the double knockout mice, suggesting that the lack of proteinase inhibition capacity was not the major problem. Therefore, we analyzed the expression of 21 different cytokines and polypeptide factors in the pancreas of all experimental groups of mice. Interleukin-1-receptor antagonist mRNA was consistently induced by the diet in the pancreas of MAM-/- mice, and transforming growth factor-beta, tumor necrosis factor-alpha, tumor necrosis factor-beta, beta-lymphotoxin, and interferon-gamma mRNA levels were also increased. The data demonstrate the important role of alpha2-macroglobulin (A2M) in acute pancreatitis as both a proteinase inhibitor and a cytokine carrier. Mice deficient in MAM and/or MUG thus offer new experimental models for defining in vivo the role of the macroglobulins in pancreatitis and in other normal and pathological processes.
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PMID:alpha2-macroglobulin- and murinoglobulin-1- deficient mice. A mouse model for acute pancreatitis. 1048 56

Although the pathophysiology of acute pancreatitis appears to be greatly influenced by the production of ascites, little is known about the mechanism. To investigate the effects of pancreatitis-associated ascitic fluid (PAAF) on macrophage function, we examined the effects of PAAF obtained from a rat model of severe acute pancreatitis on the ability of peritoneal macrophages to produce tumor necrosis factor-alpha (TNF-alpha). In addition, we compared the responses of PAAF-treated and PAAF-untreated macrophages to lipopolysaccharide (LPS) by evaluating their TNF-alpha production and nuclear factor-kappaB (NFkappaB) activation. Incubation of peritoneal macrophages with the PAAF led to the rapid and prolonged activation of NF-kappaB and to TNF-alpha production. Pyrrolidine dithiocarbamate, a potent inhibitor of NF-kappaB activation, attenuated the macrophage TNF-alpha production by PAAF. Macrophages produced TNF-alpha in response to LPS, but the cytokine production was significantly reduced when macrophages were pretreated with PAAF. The suppression of TNF-alpha production by PAAF pretreatment accompanied the impairment of NF-kappaB activation in response to LPS. These results indicate that the PAAF of severe acute pancreatitis may play important roles in the pathologic course of this disease through its effects on macrophage function.
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PMID:Ascitic fluid of experimental severe acute pancreatitis modulates the function of peritoneal macrophages. 1050 57

It has been postulated that in severely ill patients splanchnic hypoperfusion may cause endotoxin release from the gut, and this leakage of endotoxin into the circulation can trigger the cascade of inflammatory cytokines. We tested this hypothesis in 9 patients with acute severe pancreatitis by monitoring gastric intramucosal pH (pHi) as measure of splanchnic hypoperfusion at 12-h intervals trying to correlate it to endotoxin and cytokine release. Only 3 of 59 samples, obtained from 3 patients contained circulating endotoxin. Thirteen of 15 plasma samples drawn at pHi <7.20 did not contain endotoxin. The pHi was significantly lower in patients who subsequently developed 3 or more organ failures (P = 0.0017, analysis of variance). Although endotoxemia was only occasionally found, most patients had measurable interleukin 1beta (IL-1beta), interleukin 6 (IL-6), interleukin 8 (IL-8), and interleukin 10 (IL-10) in their plasma. Concentrations of IL-6, IL-8, and IL-10 on admission correlated to degree of organ dysfunction as measured by the multiple organ system failure score (P = 0.035, r = 0.74; P = 0.010, r = 0.91; P = 0.021, r = 0.82, respectively). In conclusion, patients with acute, severe pancreatitis often have splanchnic hypoperfusion and produce a wide array of cytokines despite a rare occurrence of endotoxemia.
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PMID:Intramucosal pH and endotoxin and cytokine release in severe acute pancreatitis. 1063 74

To elucidate whether pancreatic acinar cell submitted to stress is able to express TNF-alpha, we studied TNF-alpha mRNA expression by Northern blot and in situ hybridization in healthy pancreas, in tissue from caerulein-induced pancreatitis and after lipopolysaccharide (LPS) treatment. In specimens from normal pancreas, TNF-alpha mRNA expression, as judged by both Northern blot and in situ hybridization, was negative, whereas a strong but transient expression was observed in acinar cells from caerulein pancreatitis and LPS treatment. TNF-alpha mRNA appeared as rapidly as 30 min after treatment, and was maximal 6 h after. At this time, there was mild infiltration consisting mostly of polymorphonuclear leukocytes (PMNL) and no signal of TNF-alpha transcript was found in their cytoplasm. Our results strongly indicate that pancreatic acinar cell is the source of TNF-alpha early in the course of acute pancreatitis and LPS treatment, and suggest that the expression of this cytokine is a part of a general response of the acinar cell to aggression.
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PMID:Pancreatic acinar cells submitted to stress activate TNF-alpha gene expression. 1067 31

The molecular mechanisms that link acute pancreatitis and multiple organ failure remain unknown. We examined the effect of ascitic fluids prepared from rats with experimental necrotizing pancreatitis on the expression of interleukin (IL) -6 and IL-8 in human umbilical vein endothelial cells (HUVEC) and human monocytic THP-1 cells. Incubation of HUVEC or THP-1 cells with the ascitic fluids resulted in a concentration-dependent up-regulation of the cytokine expression with comparable mRNA induction. Electrophoretic mobility shift assay revealed that the ascitic fluids increased the nuclear factor-kappaB (NF-kappaB) and NF-IL6 binding activities. Intraperitoneal injection of ascitic fluids into healthy rats induced the activation of NF-kappaB in the infiltrating leukocytes in the lung. Our results suggested that ascitic fluids may play a role in the pathophysiology of severe acute pancreatitis through the activation of transcription factors and consequent cytokine productions in distant organs.
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PMID:Ascites of severe acute pancreatitis in rats transcriptionally up-regulates expression of interleukin-6 and -8 in vascular endothelium and mononuclear leukocytes. 1071 63

Induction of acute pancreatitis follows a uniform mechanism independent of the different etiologic factors such as gallstones, alcohol, ischemia, hyperlipidemia, hypercalcemia, hereditary and others. Each cause seems to affect primarily the acinar cell, resulting in premature intracellular activation of trypsinogen and other digestive enzymes. Activated enzymes and oxygen free radicals injure the acinar cell and cause a release of cytokines and vasoactive mediators, attract inflammatory cells and activate the vascular endothelium as well as the expression of adhesion molecules. The disturbance of the pancreatic microcirculation induces a progression from edematous to necrotizing pancreatitis independent of the early intracellular events, including protease activation. Specific therapy must be directed towards microperfusion failure as a secondary pathogenetic step, since the initial enzyme activation and cytokine release is irreversible by the time of clinical presentation. In experimental designs comparable to the clinical situation the following therapeutic principles have proven beneficial: increase of blood fluidity by dextran, inhibition of leukocyte-endothelium interaction by ICAM-1 antibodies, and blockade of local vasoconstriction by endothelin-receptor antagonists.
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PMID:[New pathophysiologic knowledge about acute pancreatitis]. 1078 41

Recently, there has been a great deal of interest in the role of cytokines in acute pancreatitis. Serum levels of IL-1, IL-6, and TNF-alpha have been demonstrated to be elevated in acute pancreatitis. We hypothesized that cytokines may be produced primarily by pancreatic parenchymal cells. Reasoning that ductal epithelium is the cell type most likely to be exposed to noxious stimuli in common causes of pancreatitis, such as ERCP and passage of a gallstone, we examined the response of well differentiated pancreatic ductal adenocarcinoma cell lines to stimuli known to stimulate cytokine production in other cells. CAPAN-1 and CAPAN-2 cells were incubated with endotoxin or TNF-alpha. The supernatant was assayed for production of IL-1, IL-6, and IL-8 by ELISA. The cells were assayed for activation of the transcription factor NF-kappaB by electrophoretic mobility shift assay. There was no detectable production of IL-1 by either cell line. CAPAN-1 cells had concentration-dependent production of IL-6 and IL-8 in response to both endotoxin and TNF-alpha. CAPAN-2 cells had concentration-dependent production of IL-6 and IL-8 in response to TNF-alpha. They had low level expression of IL-8 that was unaffected by any concentration of LPS, and no detectable production of IL-6 in response to LPS. These findings suggest that pancreatic duct cells may take an active part in the pathogenesis of acute pancreatitis through the production of cytokines.
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PMID:Cytokine production by CAPAN-1 and CAPAN-2 cell lines. 1079 56


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