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Cell Metabolism Jan 2008CAPS1 and CAPS2 regulate dense-core vesicle release of transmitters and hormones in neuroendocrine cells, but their precise roles in the secretory process remain...
CAPS1 and CAPS2 regulate dense-core vesicle release of transmitters and hormones in neuroendocrine cells, but their precise roles in the secretory process remain enigmatic. Here we show that CAPS2(-/-) and CAPS1(+/-);CAPS2(-/-) mice, despite having increased insulin sensitivity, are glucose intolerant and that this effect is attributable to a marked reduction of glucose-induced insulin secretion. This correlates with diminished Ca(2+)-dependent exocytosis, a reduction in the size of the morphologically docked pool, a decrease in the readily releasable pool of secretory vesicles, slowed granule priming, and suppression of second-phase (but not first-phase) insulin secretion. In beta cells of CAPS1(+/-);CAPS2(-/-) mice, the lowered insulin content and granule numbers were associated with an increase in lysosome numbers and lysosomal enzyme activity. We conclude that although CAPS proteins are not required for Ca(2+)-dependent exocytosis to proceed, they exert a modulatory effect on insulin granule priming, exocytosis, and stability.
Topics: Animals; Calcium; Calcium-Binding Proteins; Electrophysiology; Exocytosis; Immunohistochemistry; Insulin; Insulin-Secreting Cells; Islets of Langerhans; Lysosomes; Mice; Mice, Knockout; Microscopy, Confocal; Microscopy, Electron, Transmission; Nerve Tissue Proteins; Pancrelipase
PubMed: 18177725
DOI: 10.1016/j.cmet.2007.11.009 -
Alimentary Pharmacology & Therapeutics Feb 2008Various pancreatic enzyme preparations are used for the treatment of pancreatic insufficiency but their bioequivalence is often unknown. (Comparative Study)
Comparative Study
BACKGROUND
Various pancreatic enzyme preparations are used for the treatment of pancreatic insufficiency but their bioequivalence is often unknown.
AIM
To determine in vitro the pH-dependent release and acid resistance of enzymes from three commercially available pancreatin capsules, two containing enteric-coated (Creon 25000; Eurobiol 25000) and one uncoated (Eurobiol 12500) microspheres.
METHODS
Dissolution experiments were performed at pH values ranging from 4.0 to 5.8. Lipase, chymotrypsin and amylase activities were measured in the solution as a function of time.
RESULTS
Eurobiol 25000 started to release its enzymes significantly at pH 5.0 (t(1/2) = 71 min), whereas the enzymes from Creon 25000 were only released at higher pH value (5.4; t(1/2) = 49.2 min). Unlike chymotrypsin, lipase and amylase were highly sensitive to acidic conditions at the lowest pH values tested. Both enzymes were also found to be sensitive to proteolytic inactivation at the highest pH values tested. Overall, Eurobiol 25000 released higher amounts of active amylase and lipase than Creon 25000 at the pH values usually found in duodenal contents. The uncoated Eurobiol 12500 preparation was, however, the only one that could immediately release rather high levels of active chymotrypsin and lipase at low pH (4.5).
CONCLUSION
These findings suggest that pH-sensitive enteric-coated pancreatin products containing similar amounts of enzymes might not be bioequivalent depending on the pH of duodenal contents.
Topics: Amylases; Animals; Biological Availability; Chymotrypsin; Duodenum; Exocrine Pancreatic Insufficiency; Gastrointestinal Agents; Humans; Hydrogen-Ion Concentration; Lipase; Microspheres; Pancreatic Extracts; Pancrelipase; Solubility; Tablets, Enteric-Coated
PubMed: 17973644
DOI: 10.1111/j.1365-2036.2007.03563.x -
The Journal of Pediatric Pharmacology... Apr 2007OBJECTIVE Pancreatic enzyme products were available before the 1938 passage of the Federal Food, Drug, and Cosmetic Act and have to date been marketed without required...
In Vitro Comparison of Physical Parameters, Enzyme Activity, Acid Resistance, and pH Dissolution Characteristics of Enteric-Coated Pancreatic Enzyme Preparations: Implications for Clinical Variability and Pharmacy Substitution.
OBJECTIVE Pancreatic enzyme products were available before the 1938 passage of the Federal Food, Drug, and Cosmetic Act and have to date been marketed without required safety and efficacy testing. Despite a lack of demonstrated bioequivalence, they are often substituted for each other without physician or patient consent or monitoring. We investigated the in vitro variability of key performance parameters among a representative group of currently available pancreatic enzyme formulations.MATERIALS AND METHODS Three "branded" preparations (Creon 20 Minimicrospheres, Pancrease MT 20, Ultrase MT 20) and 3 "generic" formulations (Pangestyme CN-20, Pancrelipase 20,000 URL, and Lipram CR 20) were evaluated in vitro for physical parameters of the capsules, actual vs. labeled enzyme activity, resistance of the enteric coating to simulated gastric acid, and kinetics of simulated duodenal lipase release. All products were labeled as providing 20,000 units of lipase activity per capsule.RESULTS All products varied considerably in the percentage relationship between actual and labeled lipase activity. Actual lipase activity exceeded 165% of the label claim in 4 batches of the Pangestyme product and 1 batch of the Lipram product. All batches of the Creon, Lipram, Ultrase, and Pancrease products were found to have residual lipase activity above 80% of their baseline measurements after testing in simulated gastric acid; residual lipase activity varied significantly among batches of the Pangestyme product and was only 1% for the Pancrelipase product. The Creon and Lipram products demonstrated effective protection by the enteric coating at pH <6.0 and rapid release of enzymatic activity at pH ≥6.0. The Pangestyme and Pancrelipase products showed substantial activity of released enzymes already at pH 5.0. Release kinetics were inconsistent between batches for the Ultrase and Pancrease products.CONCLUSION This study confirms the existence of "branded"-to-"generic," product-to-product, and batch-to-batch variability among representative pancreatic enzyme formulations with pharmaceutically equivalent labels. The results confirm current cautions regarding pharmacy substitution of pancreatic enzyme products and support the announcement by the US Food and Drug Administration, made subsequent to this study, that as of April 2008 approved new drug applications will be required in order to ensure the quality, potency, and stability of these products.
PubMed: 23055848
DOI: 10.5863/1551-6776-12.2.115 -
Yakugaku Zasshi : Journal of the... Jan 2006In the process of investigating the hypolipidemic effects of Spirulina platensis, we found that the aqueous extract of S. platensis may inhibit the intestinal absorption...
In the process of investigating the hypolipidemic effects of Spirulina platensis, we found that the aqueous extract of S. platensis may inhibit the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity. The aqueous extract of S. platensis (500 m/kg) reduced the elevation of rat plasma triacylglycerol levels after oral administration of the lipid emulsion 2 h after administration. To clarify the hypolipidemic effects of S. platensis, the active component was isolated and designated 1'-O-(palmitonyl)-2'-O-(caprylonyl) glyceryl-beta-alpha-D-galactopyranoside (glycolipid H-b2). Glycolipid H-b2 was found to inhibit pancreatic lipase activity in a dose-dependent manner. The fractions containing glycolipid H-b2 (250 mg/kg) reduced the elevation of rat plasma triacylglycerol levels after oral administration of the lipid emulsion 2 h after administration. Furthermore, we examined the effects of phycocyanin isolated from S. platensis on pancreatic lipase activity. Phycocyanin inhibited the pancreatic lipase activity in a dose-dependent manner. These results suggest that the inhibitory effects of S. platensis on postprandial triacylglycerolemia may be due in part to the inhibition of pancreatic lipase activity by glycolipid H-b2 and phycocyanin.
Topics: Administration, Oral; Animals; Bacterial Proteins; Dose-Response Relationship, Drug; Female; Glycolipids; Hypertriglyceridemia; Male; Mice; Mice, Inbred ICR; Pancrelipase; Phycocyanin; Postprandial Period; Rats; Rats, Wistar; Spirulina
PubMed: 16394649
DOI: 10.1248/yakushi.126.43 -
Molecular and Cellular Biology May 2005beta-Cell apoptosis is a key event contributing to the pathogenesis of type 1 diabetes mellitus. In addition to apoptosis being the main mechanism by which beta cells...
beta-Cell apoptosis is a key event contributing to the pathogenesis of type 1 diabetes mellitus. In addition to apoptosis being the main mechanism by which beta cells are destroyed, beta-cell apoptosis has been implicated in the initiation of type 1 diabetes mellitus through antigen cross-presentation mechanisms that lead to beta-cell-specific T-cell activation. Caspase-3 is the major effector caspase involved in apoptotic pathways. Despite evidence supporting the importance of beta-cell apoptosis in the pathogenesis of type 1 diabetes, the specific role of caspase-3 in this process is unknown. Here, we show that Caspase-3 knockout (Casp3(-/-) mice were protected from developing diabetes in a multiple-low-dose streptozotocin autoimmune diabetes model. Lymphocyte infiltration of the pancreatic islets was completely absent in Casp3(-/-) mice. To determine the role of caspase-3-dependent apoptosis in disease initiation, a defined antigen-T-cell receptor transgenic system, RIP-GP/P14 double-transgenic mice with Casp3 null mutation, was examined. beta-cell antigen-specific T-cell activation and proliferation were observed only in the pancreatic draining lymph node of RIP-GP/P14/Casp3(+/-) mice, but not in mice lacking caspase-3. Together, our findings demonstrate that caspase-3-mediated beta-cell apoptosis is a requisite step for T-cell priming, a key initiating event in type 1 diabetes.
Topics: Animals; Apoptosis; Caspase 3; Caspases; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Glucagon; Insulin; Islets of Langerhans; Lymphocyte Activation; Mice; Mice, Knockout; Pancrelipase; T-Lymphocytes
PubMed: 15831467
DOI: 10.1128/MCB.25.9.3620-3629.2005 -
Journal of Cystic Fibrosis : Official... Dec 2002Creon 10,000 Minimicrospherestrade mark (Creon) 10,000 MMS) is a pancreatic enzyme formulation that contains smaller spheres of pancreatin in a 50% smaller capsule than... (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
Creon 10,000 Minimicrospherestrade mark (Creon) 10,000 MMS) is a pancreatic enzyme formulation that contains smaller spheres of pancreatin in a 50% smaller capsule than conventional microspheres (Creon) 8,000). This three-centre study investigated the preference of cystic fibrosis (CF) patients for these products. In one centre, 72 h stool fat excretion and coefficient of fat absorption (CFA) were also compared. Fifty-nine patients with a mean age 10 years (range 3-17) took Creon 8,000 ms for 14 days and were then randomised to 28 days of Creon 8,000 ms followed by 28 days of Creon 10,000 MMS, or vice versa. Dosing was lipase for lipase according to the labelled declaration. At the end of the second treatment period, 51 of 54 patients who completed the study expressed a preference, with a statistically significant preference in favour of Creon 10,000 MMS (47/51; 87%) vs. Creon 8,000 ms (4/51; 7.4%; P<0.0001). Stool fat (g/day) and CFA (%) were measured in 24 patients at the end of each treatment period: the products were therapeutically equivalent (Creon 10,000: 8.4 g/day, 91.3% CFA; Creon 8,000: 6.7 g/day, 93.5% CFA). Both products were well tolerated. In conclusion, in CF children we found a clear preference for Creon 10,000 MMS compared with Creon 8,000 ms with no difference in fat absorption between the two products. Creon 10,000s smaller capsules are easier to take and should aid patient compliance.
Topics: Administration, Oral; Adolescent; Child; Child, Preschool; Cross-Over Studies; Cystic Fibrosis; Exocrine Pancreatic Insufficiency; Feces; Gastrointestinal Agents; Humans; Lipids; Microspheres; Pancrelipase; Patient Satisfaction; Prospective Studies; Treatment Outcome
PubMed: 15463829
DOI: 10.1016/s1569-1993(02)00103-0 -
Pharmaceutical Research Mar 2004Side effects of diarrhea and steatorrhea diminish the therapeutic value of highly active antiretroviral therapy (HAART). We report in vitro studies of the effect of...
PURPOSE
Side effects of diarrhea and steatorrhea diminish the therapeutic value of highly active antiretroviral therapy (HAART). We report in vitro studies of the effect of HAART drugs on the activity of pancrelipase, trypsin, and enterokinase and restoration of activity by subsequent addition of excess pancrelipase or colipase.
METHODS
Commercial formulations of sixteen HAART drug formulations with solvent and four excipients were mixed with substrate. Activity of pancrelipase was recorded after addition of the enzyme; restoration of activity was monitored after addition of excess pancrelipase or colipase to the reaction mixture.
RESULTS
Five protease inhibitors (Agenerase solution, Agenerase capsules, Norvir, Viracept, Kaletra, and Fortovase) and the excipient TPGS (d-alpha-tocopheryl polyethylene glycol 1000 succinate) inhibited lipase significantly at or below physiological concentrations. Neither nucleoside reverse transcriptase inhibitors nor non-nucleoside reverse transcriptase inhibitors showed significant lipase inhibition at physiological levels. Addition of excess pancrelipase to the medium completely reversed inhibition by Agenerase, Fortovase, Norvir, and TPGS and reactivated lipase; it diminished inhibition by Kaletra and Viracept but did not completely restore activity. Addition of colipase reversed inhibition by Agenerase solution, Agenerase capsules, and TPGS; inhibition by Kaletra and Fortovase recovered slightly. No compounds tested inhibited trypsin or enterokinase.
CONCLUSIONS
These results justify evaluating protocols involving coadministration of buffered pancrelipase with protease inhibitors to reduce or eliminate diarrhea and steatorrhea in individuals being treated for HIV.
Topics: Antiretroviral Therapy, Highly Active; Excipients; HIV Infections; HIV Protease Inhibitors; Humans; Nelfinavir; Reverse Transcriptase Inhibitors; Saquinavir
PubMed: 15070091
DOI: 10.1023/B:PHAM.0000019294.03188.cf -
Biological & Pharmaceutical Bulletin Jan 2004A pancreatic lipase inhibitor, 5-hydroxy-7-(4'-hydroxy-3'-methoxyphenyl)-1-phenyl-3-heptanone (HPH), from the rhizome of Alpinia officinarum (AO) was isolated and its...
A pancreatic lipase inhibitor, 5-hydroxy-7-(4'-hydroxy-3'-methoxyphenyl)-1-phenyl-3-heptanone (HPH), from the rhizome of Alpinia officinarum (AO) was isolated and its antihyperlipidemic activity was measured. HPH inhibited a pancreatic lipase with an IC(50) value of 1.5 mg/ml (triolein as a substrate). HPH significantly lowered the serum TG level in corn oil feeding-induced triglyceridemic mice, and reduced serum triglyceride (TG) and cholesterol in Triton WR-1339-induced hyperlipidemic mice. However, HPH did not show hypolipidemic activity in high cholesterol diet-induced hyperlipidemic mice. Based on these findings, we propose that PL inhibitors may be effective as hypolipidemic agents.
Topics: Alpinia; Animals; Cholesterol; Cholesterol, LDL; Corn Oil; Enzyme Inhibitors; Heptanes; Hyperlipidemias; Indicators and Reagents; Lipids; Male; Mice; Mice, Inbred ICR; Pancrelipase; Plant Roots; Polyethylene Glycols; Triglycerides
PubMed: 14709919
DOI: 10.1248/bpb.27.138 -
Journal of Thrombosis and Haemostasis :... Dec 2003
Topics: Factor IX; Gene Expression; Hemophilia B; Humans; Lymphocytes; Pancrelipase; RNA, Messenger
PubMed: 14675105
DOI: 10.1111/j.1538-7836.2003.0543a.x -
Neoplasia (New York, N.Y.) 2003The maspin gene is not expressed in normal human pancreas, but its expression is acquired during human pancreatic carcinogenesis. In other normal human cells and their...
The maspin gene is not expressed in normal human pancreas, but its expression is acquired during human pancreatic carcinogenesis. In other normal human cells and their malignant counterparts, maspin expression is controlled through the epigenetic state of its promoter. In studies presented herein, we used bisulfite genomic sequencing and chromatin immunoprecipitation studies to show that maspin-negative pancreas cells have a methylated maspin promoter, and that the associated H3 and H4 histones are hypoacetylated. In contrast to normal pancreas, four of six human pancreatic carcinoma cell lines investigated displayed activation of maspin expression. This activation of maspin expression in pancreatic carcinoma cells was linked to demethylated promoters and hyperacetylation of the associated H3 and H4 histones. In addition, 5-aza-2'-deoxycytidine treatments activated maspin expression in the two maspin-negative pancreatic carcinoma cell lines, suggesting a causal role for cytosine methylation in the maintenance of a transcriptionally silent maspin gene. Thus, human pancreatic carcinoma cells acquire maspin expression through epigenetic derepression of the maspin locus, and in so doing appear to co-opt a normal cellular mechanism for the regulation of this gene.
Topics: Azacitidine; Carcinoma; Cell Line, Tumor; Chromatin; Cytosine; DNA Methylation; Decitabine; Dose-Response Relationship, Drug; Gene Expression Regulation; Gene Expression Regulation, Neoplastic; Genes, Tumor Suppressor; Histones; Humans; Pancreas; Pancreatic Neoplasms; Pancrelipase; Polymerase Chain Reaction; Precipitin Tests; Promoter Regions, Genetic; Protein Biosynthesis; Proteins; RNA, Messenger; Reverse Transcriptase Polymerase Chain Reaction; Serpins; Sulfites; Transcription, Genetic
PubMed: 14670180
DOI: 10.1016/s1476-5586(03)80045-3