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)

Lipase is a glycoprotein with 420-449 amino acid residues and a M(r) of 46,000-56,000 for pancreatic lipase and 32,000-39,000 for serum lipase. Lipase is present in the pancreas, intestines, and a variety of other tissues. The concentration gradient between pancreatic tissue and serum lipase is approximately 20,000-fold. Serine, as part of an Asp-His-Ser triad, is the nucleophilic residue essential for catalysis. Lipase differs from other esterases by the presence of a hydrophobic recognition site. The optimal pH is between 7.5 and 10.0, depending on the reaction condition; the pI for the various forms of the enzyme has been reported as 5.80 and 5.85; 6.4, 6.8, and 7.0; and 7.4 for a purified fraction. Several authors report the presence of two molecular forms in the pancreas and three electrophoretic bands with lipolytic activity. In normal serum two bands have been observed; in pancreatitis as many as four bands have been seen. Lipolytic activity may not always be due to lipase. Assays specific for lipase require a triglyceride as substrate as well as the presence of colipase (a water-soluble and heat-stable protein, essential for lipase action), a secondary bile salt, and Ca2+. The clinical sensitivity of all modern assays is high because of selection of a low decision limit; the clinical specificity varies greatly but can be improved by increasing the cutoff point. Lipase determinations in pancreatitis are superior to amylase determinations. The reasons for the great variability of reports regarding the clinical utility of lipase are discussed, and the clinical utility of lipase determinations is summarized.
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PMID:Lipase in serum--the elusive enzyme: an overview. 848 65

Two-dimensional gel electrophoresis (2-DE) was used to study protein degradation in human pure pancreatic juice (PPJ) which was collected at 5 min intervals for 20 min by selective endoscopic cannulation of the main pancreatic duct. In PPJ collected from healthy subjects no significant degradation was observed by incubating PPJ at 37 degrees C up to 6 h. By further incubation for 24 h, glycoprotein-1, procarboxypeptidase A-1 and lipase were nearly completely degraded, while alpha-amylase and procarboxypeptidase B-1 were not degraded under these conditions; alpha-amylase became labile in the presence of 1 mM ethylene diaminetetraacetic acid (EDTA) or 10 mM phenyl methyl sulfonyl fluoride (PMSF). Protein degradation was observed by 2-DE of an initial fraction of PPJ collected from patients with chronic calcific pancreatitis (CCP). The 2-DE patterns of subsequent fractions resembled those of PPJ from healthy subjects. The mixture of the last fraction with the initial fraction showed significant protein degradation, inhibited by adding aprotinin. Furthermore, the extent of protein degradation correlated with the dilatation of the main pancreatic duct as a consequence of intraductal stagnation of pancreatic juice. These findings demonstrate that protein degradation in PPJ is accelerated by intraductal activation of serine proteases in the case of patients with CCP. 2-DE of PPJ from patients with CCP provides useful information for the evaluation of intraductal activation of zymogens and the progress of chronic pancreatitis.
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PMID:Protein degradation in human pure pancreatic juice analyzed by two-dimensional gel electrophoresis. 873 47

Antithrombin III (AT III) is the physiological inhibitor of thrombin and other serine proteases of the clotting cascade. In the development of sepsis, septic shock and organ failure, the plasma levels of AT III decrease considerably, suggesting the concept of a substitution therapy with the inhibitor. A decrease of AT III plasma levels might also be associated with other pathological disorders like trauma, burns, pancreatitis or preclampsia. Activation of coagulation and consumption of AT III is the consequence of a generalized inflammation called SIRS (systemic inflammatory response syndrome). The clotting cascade is also frequently activated after organ transplantation, especially if organs are grafted between different species (xenotransplantation). During the past years AT III has been investigated in numerous corresponding disease models in different animal species which will be reviewed here. The bulk of evidence suggests, that AT III substitution reduces morbidity and mortality in the diseased animals. While gaining more experience with AT III, the concept of substitution therapy to maximal baseline plasma levels (100%) appears to become insufficient. Evidence from clinical and preclinical studies now suggests to adjust the AT III plasma levels to about 200%, i.e., doubling the normal value. During the last few years several authors proposed that AT III might not only be an anti-thrombotic agent, but to have in addition an anti-inflammatory effect.
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PMID:Antithrombin III in animal models of sepsis and organ failure. 951 81

Gabexate mesylate (GM; commercialized under the brand name FOY) is a nonantigenic synthetic inhibitor of plasmatic and pancreatic serine proteinases that is used therapeutically in the treatment of pancreatitis and disseminated intravascular coagulation and as a regional anticoagulant for hemodialysis. The inhibitory effect of GM on nitric oxide synthase as well as serine proteinases and swine kidney copper amine oxidase, all acting on cationic substrates, has been investigated. On the basis of the available X-ray crystal structures of the enzymes considered, the possible binding mode(s) of GM has(have) been analyzed. The enzyme cross-inhibition by GM suggests that the use of this drug should be under careful control. With the aim to improve the scarce plasma stability of GM, the positively charged drug has been complexed to the surface of preformed anionic liposomes. The liposome-complexed GM half-life increases about five-fold, indicating the protective effect of liposomes on GM degradation. Moreover, the GM complexation with liposomes does not alter its inhibitory activity on NOS-I and porcine pancreatic trypsin.
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PMID:Cross-enzyme inhibition by gabexate mesylate: formulation and reactivity study. 981 86

The difficulty in an early diagnosis of pancreatic cancer is in the absence of early symptoms due to lower limit of detection of the actual imaging techniques. Clinical symptoms like weight loss, abdominal pain and jaundice indicate an advanced cancer stage. Today 50% of pancreatic tumors are diagnosed in advanced metastatic stage and only 20-30% show resectable cancer. Ultrasound and determination of a mucine like antigen as CA 19-9, CA 50 and CA 195 seem to allow an earlier diagnosis with a higher rate of resective surgery and a prolonged survival for these patients. The mucines are high molecular weight glycoproteins consistent of a backbone protein to which oligosaccarides are attached. The linkage of carbohydrate to the peptide is termed O-glycosidic and involves the hydroxylic groups of serine or threonine with N-acetylglucosamine. Only the backbone proteins are genetically determined (genes MUC). The gangliosides are the same or derivative of Lewis antigen. CA 19-9, CA 50 and CA 195 are assays directed to different epitopes probably present on the same mucinous antigen. These epitopes are not present in different mucines as CA 15-3, CA 125 and TAG 72. Recently other two mucines are emploied CA 242 and CAM 17.1 but they are not better than CA 19-9. The use of a "triplet" of tumor markers as CA 19-9, CA 125 and CEA is the best diagnostic tool for cancer of pancreas in an "integrated" use with ultrasonographic evaluation of the lesion. CA 19-9 permits differential diagnosis from neuroendocrine tumor or pancreatitis, the values of CA 125 and CEA are useful in the evaluation of the stage, resectability and prognosis of pancreatic cancer. The recent use of CA19-9 for the evaluation of radiochemotherapy in preoperative management of the patient is a mode of a well known application of tumor markers in a kinetic evaluation of the tumor for the radicality of therapy, follow-up, recurrence and the effectiveness of the palliative therapy.
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PMID:[Tumor markers in the diagnosis of pancreatic cancer]. 1023 75

Autodigestion by proteolytic enzymes is thought to represent the critical mechanism by which acute pancreatitis is initiated. Where and why pancreatic proteases, which are physiologically stored and secreted as inactive precursor zymogens, are activated within the pancreas has remained controversial. Here we present data which indicate that: the lysosomal protease cathepsin B can activate trypsinogen in vitro in a manner that is similar to trypsinogen activation by enterokinase; that cathepsin B colocalizes with trypsinogen in the secretory compartment of the rat pancreas and of the human pancreas; that trypsinogen activation begins in a secretory compartment that is distinct from mature zymogen granules; and that the inhibition of cathepsin B can either increase or decrease premature trypsinogen activation depending on the concentration of the inhibitor, its specificity and its site of action in the pancreatic acinar cell. These observations elucidate some of the complex relations between cysteine and serine proteases in the pancreas with respect to their mechanisms of activation, their subcellular sites of action, and their possible role in the onset of pancreatitis.
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PMID:The role of cysteine proteases in intracellular pancreatic serine protease activation. 1084 66

The pancreatic acinar cell is potentially the initial site of injury that begins the series of events leading to acute pancreatitis. Pathological intrapancreatic zymogen activation occurs in experimental pancreatitis in animals and in human pancreatitis. Intracellular activation has been clearly linked to aberrant zymogen processing in one form of hereditary pancreatitis; in this genetic disease a mutation in cationic trypsinogen may eliminate the degradation of any trypsin activated in the acinar cell. Recent studies have also provided the first direct evidence that trypsinogen activation takes place early in the course of caerulein-induced pancreatitis; parallel studies have used isolated pancreatic acini and conditions that simulate those that cause pancreatitis in vivo to demonstrate that zymogens can be pathologically activated in isolated cells. A unique acinar cell pathway regulates the intracellular proteinase processing of zymogens to their active forms. Stimulating the acinar cell with supramaximal concentrations of cholecystokinin (CCK) or carbamylcholine can activate this pathway. The activation depends on a low pH compartment within the acinar cell and activation of an intracellular serine protease. A marker of trypsinogen processing, the trypsinogen activation peptide (TAP), is generated in acinar cell compartments that do not overlap with secretory granules. This compartment overlaps with a marker of recycling endosomes and lysosomes. Thus, zymogen processing within the acinar cell proceeds in a distinct subcellular compartment and is dependent on a low pH environment and activation of serine proteases.
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PMID:Mechanisms of intracellular zymogen activation. 1103 Jun 3

Gabexate mesylate is a non-antigenic synthetic inhibitor of trypsin-like serine proteinases that is therapeutically used in the treatment of pancreatitis and disseminated intravascular coagulation and as a regional anticoagulant for hemodialysis. Considering the structural similarity between gabexate mesylate and arginine-based inhibitors of trypsin-like serine proteinases, the effect of gabexate mesylate on human and bovine mast cell tryptase action was investigated. Values of the inhibition constant (K(i)) for gabexate mesylate binding to human and bovine tryptase were 3.4 x 10(-9) M and 1.8 x 10(-7) M (at pH 7.4 and 37.0 degrees ), respectively. Furthermore, gabexate mesylate inhibited the fibrinogenolytic activity of human tryptase. On the basis of the available x-ray crystal structure of human tryptase, the possible binding mode of gabexate mesylate to human and bovine tryptase was analyzed. Human tryptase inhibition by gabexate mesylate may account for the reported prevention of inflammation, erosion, and ulceration of skin and mucosae.
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PMID:Selective inhibition of human mast cell tryptase by gabexate mesylate, an antiproteinase drug. 1117 30

Whole-blood free amino acids were measured in a control group made up of eight healthy women fasted for 12 h and also in eight patients with acute pancreatitis, five patients with acute cholecystitis and seven patients with acute appendicitis. Blood was withdrawn immediately on admission to hospital and again 3 d later following a controlled peripheral parenteral nutrition diet; this is with the exception of the appendicitis group. l-Cystathionine and l-methionine concentrations were significantly higher in pancreatitis and appendicitis patients when compared with controls. In the pancreatitis and cholecystitis patients, l-serine concentration was also significantly higher when compared with controls. The l-homocysteine concentration was significantly higher only in the appendicitis group when compared with the control group. l-Cystine concentration was unchanged in all the patients studied when compared with control subjects. The l-methionine : l-cystine ratio was significantly higher and the l-glutamine : l-cystine ratio was significantly lower in all the patients when compared with controls. The blood S-amino acid pattern reflects an impairment in liver transsulfuration pathway during acute abdominal processes. This work supports the idea that the l-methionine : l-cystine and l-glutamine : l-cystine ratios can be taken as good markers to evaluate the S-amino acid metabolism and suggests the importance of using N-acetylcysteine as a required nutrient in these situations.
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PMID:Blood sulfur-amino acid concentration reflects an impairment of liver transsulfuration pathway in patients with acute abdominal inflammatory processes. 1124 85

A group of 16-kDa proteins, synthesized and secreted by rat pancreatic acinar cells and composed of pancreatic stone protein (PSP/reg) and isoforms of pancreatitis-associated protein (PAP), show structural homologies, including conserved amino acid sequences, cysteine residues, and highly sensitive N-terminal trypsin cleavage sites, as well as conserved functional responses in conditions of pancreatic stress. Trypsin activation of recombinant stress proteins or counterparts contained in rat pancreatic juice (PSP/reg, PAP I and PAP III) resulted in conversion of 16-kDa soluble proteins into 14-kDa soluble isoforms (pancreatic thread protein and pancreatitis-associated thread protein, respectively) that rapidly polymerize into insoluble sedimenting structures. Activated thread proteins show long lived resistance to a wide spectrum of proteases contained in pancreatic juice, including serine proteases and metalloproteinases. In contrast, PAP II, following activation with trypsin or pancreatic juice, does not form insoluble structures and is rapidly digested by pancreatic proteases. Scanning and transmission electron microscopy indicate that activated thread proteins polymerize into highly organized fibrillar structures with helical configurations. Through bundling, branching, and extension processes, these fibrillar structures form dense matrices that span large topological surfaces. These findings suggest that PSP/reg and PAP I and III isoforms consist of a family of highly regulated soluble secretory stress proteins, which, upon trypsin activation, convert into a family of insoluble helical thread proteins. Dense extracellular matrices, composed of helical thread proteins organized into higher ordered matrix structures, may serve physiological functions within luminal compartments in the exocrine pancreas.
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PMID:A family of 16-kDa pancreatic secretory stress proteins form highly organized fibrillar structures upon tryptic activation. 1127 30


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