Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Trypsinogen”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources
PubMed1988

The ontogeny of serum immunoreactive pancreatic lipase and cationic trypsinogen in the premature human infant.

We evaluated the development of the exocrine pancreas in 16 healthy preterm infants (29.3 +/- 1.6 weeks). The infants were fed breast milk with formula supplements (n = 8) or formula alone (n = 8). Growth was monitored weekly for 12 weeks then at 3, 6, 9, 12 months. At the same intervals sera were determined for pancreatic lipase and cationic trypsinogen. In addition, cord blood samples were analysed from another 33 preterm (27.6 +/- 5.2 weeks) and 75 healthy full-term infants. Serum pancreatic lipase in the cord blood of term (3.7 +/- 0.4 micrograms/l) and preterm infants (1.8 +/- 0.2 micrograms/l) was significantly below values reported for older children (10.5 +/- 0.9 micrograms/l; p less than 0.001). In the preterm infant, serum lipase was also significantly lower than values obtained at term (p less than 0.001). At birth, serum trypsinogen for preterm (16.8 +/- 1.3 micrograms/l) and term infants (23.3 +/- 1.9 micrograms/l) were below those for older children (31.4 +/- 3.7 micrograms/l; p less than 0.05). Over the first 3 weeks of life, serum lipase and trypsinogen increased significantly. From 3 weeks to 12 months of age, serum trypsinogen values remained unchanged, but serum lipase increased dramatically after 10 weeks of age. Thus, at 6 and 12 months of age, the preterm infants had significantly higher serum lipase values than infants of the same age born at term. These two pancreatic enzymes appear to show independent age-related maturation in infants born before term. The rate of maturation of lipase appears to be accelerated by exposure to the extrauterine environment.

Aging↗
PubMed2000

Heat shock protein 70 prevents secretagogue-induced cell injury in the pancreas by preventing intracellular trypsinogen activation.

Rodents given a supramaximally stimulating dose of cholecystokinin or its analogue cerulein develop acute pancreatitis with acinar cell injury, pancreatic inflammation, and intrapancreatic digestive enzyme (i.e., trypsinogen) activation. Prior thermal stress is associated with heat shock protein 70 (HSP70) expression and protection against cerulein-induced pancreatitis. However, thermal stress can also induce expression of other HSPs. The current studies were performed using an in vitro system to determine whether HSP70 can actually mediate protection against pancreatitis and, if so, to define the mechanism underlying that protection. We show that in vitro exposure of freshly prepared rat pancreas fragments to a supramaximally stimulating dose of cerulein results in changes similar to those noted in cerulein-induced pancreatitis, i.e., intra-acinar cell trypsinogen activation and acinar cell injury. Short-term culture of the fragments results in HSP70 expression and loss of the pancreatitis-like changes noted after addition of cerulein. The culture-induced enhanced HSP70 expression can be prevented by addition of either the flavonoid antioxidant quercetin or an antisense oligonucleotide to HSP70. Under these latter conditions, addition of a supramaximally stimulating concentration of cerulein results in trypsinogen activation and acinar cell injury. These findings indicate that the protection against cerulein-induced pancreatitis that follows culture-induced (and possibly thermal) stress is mediated by HSP70. They suggest that the HSP acts by preventing trypsinogen activation within acinar cells.

Animals↗
PubMed1996

Serum trypsinogen-2 in the prediction of outcome in acute necrotizing pancreatitis.

BACKGROUND: The accuracy of serum trypsinogen-2 in predicting the severity of acute necrotizing pancreatitis (ANP) was prospectively evaluated in 52 consecutive patients. METHODS: A new sensitive immunofluorometric assay was used for serum trypsinogen-2, RESULTS: Mean values during the first 24 h were 42.1 micrograms/l in control patients, 1435 micrograms/l in uncomplicated cases, and 4090 micrograms/l in complicated or fatal cases. There was a significant difference in serum trypsinogen-2 values between patients with uncomplicated and complicated disease (p = 0.002) already on admission. When a cutoff level of 1000 micrograms/l was used, patients with uncomplicated ANP were differentiated from patients with complicated ANP with a sensitivity of 91% and with a specificity of 71%. CONCLUSIONS: The immunofluorometric assay of serum trypsinogen-2 is a sensitive and specific method for prediction of the severity of the disease in necrotizing pancreatitis.

Adult↗
PubMed1980

Dose-related inhibition of gastric secretion by intraduodenal trypsinogen in dogs.

It has been shown previously that trypsinogen and its activation peptide but not trypsin decreased gastric secretion. The purpose of this work was to study the dose-action relation between the intraduodenal infusion of trypsinogen and gastric secretion. Three dogs provided with gastric and duodenal Thomas fistulae were stimulated by continuous i.v. perfusion of porcine gastrin I-II (6 microgram kg-1 h-1). Pancreatic juice was diverted to the exterior and gastric secretion was collected. Upon reaching a gastric secretory plateau, porcine trypsinogen was infused intraduodenally at doses of 5, 10, 20, 40, 80 and 160 mg. Each test was continued for a further 60 min. Control was made with isotonic saline. There was a dose-related inhibition of the gastrin-stimulated gastric acid output. This inhibition reached a maximum of 50% with 40 mg of intraduodenal trypsinogen, showing no increase with higher doses.

Animals↗
PubMed2005

Effect of endothelin-1 receptor antagonists on histological and ultrastructural changes in the pancreas and trypsinogen activation in the early course of caerulein-induced acute pancreatitis in rats.

AIM: To assess the effect of non-selective ET(A/B) (LU 302872) and selective ET(A) (LU 302146) antagonist on pancreatic histology and ultrastructure of acinar cells in connection with trypsinogen activation in early caerulein-induced AP. METHODS: Male Wistar rats with caerulein-induced AP, lasting 4 h, were treated i.p. with 10 and 20 mg/kg b.w. of each antagonist. Edema, inflammatory infiltration, necrosis and vacuolization of acinar cells in the pancreas were scored at 0-3 scale. Free active trypsin (FAT), total potential trypsin (TPT) after activation with enterokinase, and index of trypsinogen activation (%FAT/TPT) were assayed in pancreatic homogenates. RESULTS: In untreated AP, the edema, inflammatory infiltration, necrosis and vacuolization increased as compared to control healthy rats (P<0.01). None of the treatment exerted any meaningful effect on the edema and inflammatory infiltration. The selective antagonist increased slightly the necrosis score to 0.82+/-0.06 at higher dose (P<0.05) vs 0.58+/-0.06 in untreated AP. The non-selective antagonist increased slightly the vacuolization score to 2.41+/-0.07 at higher dose (P<0.01) vs 1.88+/-0.08 in untreated AP. The decrease in the number of zymogen granules, disorganization of endoplasmic reticulum, autophagosomes and cytoplasmic vacuoles were more prominent in treated AP than in untreated AP groups. %FAT/TPT in untreated AP increased about four times (18.4+/-3.8 vs 4.8+/-1.3 in control group without AP, P<0.001). Treatment of AP with both antagonists did not affect significantly augmented trypsinogen activation. CONCLUSION: The treatment with endothelin-1 receptors (non-selective ET(A/B) and selective ET(A)) antagonists has essential effect neither on the edema and inflammatory infiltration nor on trypsinogen activation observed in the early course of caerulein-induced AP. Nevertheless a slight increase of the necrosis and vacuolization score and some of the ultrastructural data could suggest the possibility of their undesired effects in caerulein-induced AP at investigated doses.

Acute Disease↗
PubMedDate not supplied

Mechanism and role of trypsinogen activation in acute pancreatitis.

In healthy subjects, the 3 known pancreatic trypsinogens, which are endopeptidases belonging to the chymotrypsin superfamily, are activated by enterokinase and partial autoactivation in the duodenum. The premature activation of trypsinogen in the pancreatic interstitium, with the subsequent activation of other pancreatic zymogens, is believed to lead to the autodigestion of the gland, this being the first event in acute pancreatitis. The mechanisms that lead to trypsinogen, activation in acute pancreatitis are largely unknown. However, ischemia, hypercalcemia and the activation of cathepsin B (by cholecystokinin) are thought to be of importance. The easiest and most reliable way to assess trypsinogen activation is the measurement of the activation peptide, TAP, in urine, plasma, pancreatic tissue or ascitic fluid. In the animal model of acute pancreatitis, TAP in ascites and pancreatic tissue has been shown to correlate with the presence and extent of necroses. It has proven to be a good marker for the severity of pancreatitis and is a useful marker in examining the pathophysiology and possible treatment modalities in the animal model of acute pancreatitis. Studies on TAP in human acute pancreatitis were most commonly focused on urinary TAP. Within a 48-hour time frame after the onset of the disease, TAP was a good predictor of the severity of acute pancreatitis. The main advantage over other markers, such as CRP, is that TAP is the earliest marker of necrosis to be increased. Also, increased levels of TAP in ascitic fluid were shown to correlate well with pancreatic necroses. In our experience, plasma TAP was found to have a "diagnostic window" within the first 3 days predicting pancreatic necroses. Positive TAP gave a very good positive prediction and a high specificity towards the development of pancreatic necroses, but did not differ between necrotizing pancreatitis with systemic complications or uncomplicated necrotizing pancreatitis. We therefore think that plasma TAP is a very good marker for local complication in acute pancreatitis and its routine measurements may help to identify patients at a high risk within the first days of the disease.

Acute Disease↗
PubMed2004

[Cationic trypsinogen gene mutation in patients with chronic idiopathic pancreatitis].

BACKGROUND/AIMS: Mutation of Cationic trypsinogen gene is clearly associated with hereditary pancreatitis and plays an important role in the pathogenesis of pancreatitis. According to literature, this mutation is occasionally occurred in patients with pancreatitis in Western countries and Japan. The aim of this study was to find out whether the mutation was observed in Korean patients with chronic idiopathic pancreatitis. METHODS: Peripheral blood samples of 11 patients with chronic idiopathic pancreatitis were collected consecutively, and DNA was extracted from the samples. Polymerase chain reaction was performed in exon 2 and 3 of cationic trypsinogen gene. Then, DNA products were purified and sequenced. RESULTS: The mutation was not found in exon 2 and 3 of cationic trypsinogen gene in these patients. CONCLUSIONS: There was no cationic trypsinogen mutation in Korean patients with chronic idiopathic pancreatitis. Further large sampled cohort study is needed.

Adolescent↗
PubMed2004

Evaluation of the cationic trypsinogen gene for potential mutations in miniature schnauzers with pancreatitis.

The purpose of this study was to evaluate the cationic trypsinogen gene in miniature schnauzers for possible mutations. Genetic mutations have been linked with hereditary pancreatitis in humans. Four miniature schnauzers were selected on the basis of a clinical history of pancreatitis. One healthy miniature schnauzer and 1 healthy mixed breed canine were enrolled as controls. DNA was extracted from these canines using a commercial kit. Primers were designed to amplify the entire canine cationic trypsinogen cDNA sequence. A polymerase chain reaction (PCR) was performed and products were purified and sequenced. All sequences were then compared. The healthy control canine, a healthy miniature schnauzer, and the 4 miniature schnauzers with pancreatitis showed identical sequences of the cationic trypsinogen gene to the published sequence. We conclude that, in contrast to humans with hereditary pancreatitis, mutations of the cationic trypsinogen gene do not play a major role in the genesis of pancreatitis in the miniature schnauzer.

Amino Acid Sequence↗
PubMed1991

Non-parallel secretion of pancreatic amylase and trypsinogen following hepatectomy in rats.

To explore the changes in exocrine pancreatic function in the stages of active regeneration and recovery after hepatectomy, we measured the caerulein-stimulated amylase and trypsinogen output in anesthetized rats 4 days and 8 days after about 70% hepatectomy. Both 4 days and 8 days after hepatectomy, the amylase output was significantly greater than in the control groups. On the other hand, 4 days after hepatectomy, the trypsinogen output was almost the same as in the control groups, and 8 days after hepatectomy, it was significantly lower than in the control groups. Thus, the secretion of amylase and trypsinogen 8 days after hepatectomy was not parallel. The amylase content of the pancreas was significantly larger after hepatectomy than in the control groups, but the trypsinogen content was significantly smaller. These results indicate a non-parallel secretion of pancreatic digestive enzymes, as well as differences in the functions of the acinar cells after partial hepatectomy, and the important role of amylase in glucose metabolism after hepatectomy.

Amylases↗
PubMed1975

Refolding of reduced, denatured trypsinogen and trypsin immobilized on Agarose beads.

The reoxidation of fully reduced and denatured bovine trypsinogen and the regeneration of the native structure can be accomplished if the protein is initially attached to Agarose beads. Reoxidation was performed under aerobic conditions, in the presence of mercaptoethanol and dehydroascorbate or with a mixture of reduced and oxidized glutathione. In 24 hours, the yields of regenerated trypsinogen were 60 to 70% with 0.2 to 0.6 mg of protein bound/ml of gel but 30% or less if greater than 1.7 mg of protein were bound. Rapid reoxidation, with dehydroascorbate as catalyst, gave molecules which could not be converted to active trypsin. However, if the incorrectly folded structures were placed in a mixture of reduced and oxidized glutathione, the molecules underwent disulfide interchange and could continue to refold. The rapidly reoxidized molecules regained their native structure with the same rate and to the same extent as they did initially in the absence of rapid reoxidation. Therefore, the rate-limiting step in the refolding of trypsinogen was disulfide interchange. The regenerated Agarose-bound trypsinogen displayed the usual properties of the native molecule in (a) its conversion to active trypsin by a process of limited proteolysis, (b) the kinetic constants of the activated product toward typical trypsin substrates, and (c) the limited cleavage of 1 disulfide bond with sodium borohydride. Refoldind of immobilized trypsin was also observed with an overall yield of 50%. Trypsin can fold spontaneously to its native structure even though it lacks the NH2-terminal hexapeptide of its precursor.

Animals↗
PubMed1979

Refolding of the mixed disulfide of bovine trypsinogen and glutathione.

The mixed disulfide of bovine trypsinogen and glutathione refolded with high yields at protein concentrations of 20 microgram/ml or less, at 4-25 degrees C, pH 8.0 to 8.7, in the presence of 3 to 6 mM cysteine under anaerobic conditions. The regenerated protein behaved as native trypsinogen as judged by gel exclusion chromatography, isoelectric focusing, and activation with bovine enterokinase or trypsin. However, refolded samples that were quenched with iodoacetate and analyzed by disc gel electrophoresis formed two components corresponding to trypsinogen and S-(carboxymethylcysteine)2-(179-203)-trypsinogen. The use of cysteine as a disulfide interchange catalyst caused reduction of the 179 to 203 disulfide bond, and quenching of the refolding mixture with iodoacetate produced the carboxymethylated derivative. The overall yield of the regenerated product was 70% and the half-time at 4 degrees C was 55 min.

Animals↗
PubMed2002

Effect of operating variables on the yield of recombinant trypsinogen for a pulse-fed dilution-refolding reactor.

The inclusion body process route for manufacturing proteins offers distinct process advantages in terms of expression levels and the ease of initial inclusion body recovery. The efficiency of the refolding unit operation, however, does determine the overall economic feasibility of a process. Dilution refolding is the simplest and most extensively used refolding operation, although significant yield losses often occur due mainly to aggregation. Operating variables may have a significant effect on the degree of aggregation, but a systematic study has not been reported. This study investigates the effect of operating variables on the dilution refolding of solubilized r-trypsinogen inclusion bodies in a pulse-fed stirred reactor. Variables investigated were inclusion body washing, stirring speed, feed rate, concentration of solubilized r-trypsinogen, and concentration of urea during solubilization of the inclusion bodies. Additionally, the effect of baffles in the reactor was investigated. The yield of renatured r-trypsinogen varied between 12 +/- 0.2% and 21 +/- 1.0% depending on the specific combination of operating variables employed. It is clear that a suboptimal operating strategy can significantly reduce protein yield. In particular, we note that an increased intensity of mixing adversely affected yield in contrast to previous reports indicating that enhanced dispersion increases yield. We conclude that yield is determined not only by the efficiency of dispersion, but also by the local chemical environment of the protein as it folds, and the rate of change of this environment. This will be controlled by micromixing effects, and hence the intensity of agitation, in a complex manner requiring further characterization.

Bioreactors↗
PubMed1991

Human colon carcinoma, fibrosarcoma and leukemia cell lines produce tumor-associated trypsinogen.

Previous studies have indicated that cyst fluid of ovarian tumors contains 2 trypsinogen isoenzymes, called tumor-associated trypsinogen-I (TAT-I) and trypsinogen-2 (TAT-2), the levels of which correlate with the degree of malignancy of the tumors. In addition, these cyst fluids contain large amounts of tumor-associated trypsin inhibitor (TATI), which is also expressed in many other human tumors. In the present study we examined the production of TAT-I, TAT-2 and TATI in 9 established tumor-cell lines. TAT-2 was produced by 5 cell lines. Its concentration in the conditioned medium of COLO 205 colon adenocarcinoma cells, K-562 erythroleukemia cells and fibrosarcoma cell lines HT 1080, 8387 and A 9733 was 460 micrograms/l, 9.8 micrograms/l, 21 micrograms/l, 8.8 micrograms/l and 0.24 micrograms/l, respectively. TAT-I was detectable in the conditioned medium of COLO 205 and HT 1080 cells at concentrations of 64 micrograms/l and 0.5 micrograms/l, respectively. TATI was detected only in the media of COLO 205 cells at a concentration of 23 micrograms/l. TAT-2 zymogen was purified from the conditioned medium of COLO 205 and HT 1080 cells by immunoaffinity chromatography. According to its aminoterminal amino acid sequence, a molecular mass of 28 kDa by SDS-PAGE, elution pattern in ion-exchange chromatography and ability to be activated by enteropeptidase, the zymogen is identical to that previously isolated from cyst fluid of ovarian tumors. In addition, we found that TAT-2 secretion could be down-regulated by dexamethasone in HT 1080 cells but not in COLO 205 cells. The abundant production of TAT-2 isoenzyme in different cancer cell lines suggests that it could contribute to the increased proteolytic activity of many human tumors.

Carcinoma↗
PubMed1988

Zymogen activation: effect of peptides sequentially related to the bovine beta-trypsin N-terminus on Kazal inhibitor and benzamidine binding to bovine trypsinogen.

The activating effect of peptides sequentially related to the Ile 16-Val17-Gly18 N-terminus of bovine beta-trypsin (namely Ile-Val-Gly, Ile-Val, Ile-Leu, Ile-Ala, Val-Val, Leu-Val, and Val-Leu) on the thermodynamic parameters for the binding of the porcine pancreatic secretory trypsin inhibitor (Kazal inhibitor) and benzamidine to bovine trypsinogen was investigated at pH 5.5 (Bis tris-HCl buffer, I = 0.1 M) and T = 21 +/- 0.5 degrees C. Thermodynamic parameters for Kazal inhibitor and benzamidine association to the binary peptide/zymogen adducts are more favorable than those observed for ligand binding to the proenzyme alone, although never as much as those reported for the formation of bovine beta-trypsin/Kazal inhibitor and bovine beta-trypsin/benzamidine adducts. Analogously, the affinity of activating peptides for the binary proenzyme/Kazal inhibitor and binary proenzyme/benzamidine complexes is higher than that observed for peptide binding to free bovine trypsinogen. Differences in affinity for ligand binding to free bovine trypsinogen, to its binary adducts and to bovine beta-trypsin suggest the presence of different activation levels of the proenzyme, none of which structurally coincide with that achieved in bovine beta-trypsin. The existence of different discrete states suggests that the zymogen-to-active enzyme transition should not be considered as a two-state process but as a multistep event.

Amidines↗
PubMed1995

Description of an automated method for the in vitro measurement of trypsinogen secretion from pancreatic segments.

The characterization of trypsinogen output from superfused pancreatic tissue by an automated spectrophotometric method is described. To test the method we investigated the time-course and the dose-response curve for acetylcholine-induced trypsinogen release from superfused pancreatic segments. We have demonstrated that this method allows the on-line detection and estimation of trypsinogen release with suitability, stability, and sensitivity.

Acetylcholine↗
PubMed1999

Trypsinogen stabilization by mutation Arg117-->His: a unifying pathomechanism for hereditary pancreatitis?

Mutations Arg117-->His and Asn21-->Ile of the human cationic trypsinogen have been recently identified in patients affected by hereditary pancreatitis (HP). The Arg117-->His substitution is believed to cause pancreatitis by eliminating an essential autolytic cleavage site in trypsin, thereby rendering the protease resistant to inactivation through autolysis. Here we demonstrate that the Arg117-->His mutation also significantly inhibits autocatalytic trypsinogen breakdown under Ca(2+)-free conditions and stabilizes the zymogen form of rat trypsin. Taken together with recent findings demonstrating that the Asn21-->Ile mutation stabilizes rat trypsinogen against autoactivation and consequent autocatalytic degradation, the observations suggest a unifying molecular pathomechanism for HP in which zymogen stabilization plays a central role.

Animals↗
PubMed2000

Gain-of-function mutations associated with hereditary pancreatitis enhance autoactivation of human cationic trypsinogen.

Hereditary pancreatitis (HP), an autosomal dominant disorder, has been associated with mutations in the cationic trypsinogen gene. Here we demonstrate that the two most frequent HP mutations, Arg117 --> His and Asn21 --> Ile, significantly enhance autoactivation of human cationic trypsinogen in vitro, in a manner that correlates with the severity of clinical symptoms in HP. In addition, mutation Arg117 --> His inhibits autocatalytic inactivation of trypsin, while mutation Asn21 --> Ile has no such effect. The findings strongly argue that increased trypsinogen activation in the pancreas is the common initiating step in both forms of HP, whereas trypsin stabilization might also contribute to HP associated with the Arg117 --> His mutation.

Catalysis↗
PubMed2001

Effect of hyperthermia on premature intracellular trypsinogen activation in the exocrine pancreas.

Hyperthermia, raising the body temperature from normal to above 40 degrees C, has been shown to prevent pancreatitis in an experimental animal model of the disease, but the underlying cellular mechanisms of this protection remain unknown. We induced controlled hyperthermia in either laboratory rats and isolated pancreatic acini or, alternatively, raised the temperature of pancreatic homogenates in vitro from 37 to 41 degrees C. In vitro controlled hyperthermia of up to 41 degrees C increased the autoactivation-induced and enterokinase-induced trypsinogen activation as well as free trypsin activity. Conversely, in whole animal studies and in living acinar cells hyperthermia reduced or abolished premature intracellular trypsinogen activation in a time- and temperature-dependent manner and this protective effect was independent of either de novo protein synthesis, interference with acinar cell signal transduction, or confirmational changes in pancreatic trypsinogen. We conclude that hyperthermia, in a manner that is independent of the synthesis of pancreatic chaperone or heat shock proteins, can directly abolish the earliest initiating event involved in the onset of pancreatitis, namely the premature and intracellular activation of digestive zymogens.

Animals↗