Effect of Intravenous Iron Administration on Bone Mineral and Iron Homeostasis in Patients with Inflammatory Bowel Disease-Results of a Prospective Single-Centre Study.

INTRODUCTION: Anaemia and bone metabolism alterations are common in inflammatory bowel disease (IBD), which is a heterogeneous group of diseases that include Crohn's disease (CD) and ulcerative colitis (UC) with a rich intestinal and extraintestinal symptomatology. All these make the diagnostic procedures complicated and difficult. PURPOSE AND SCOPE: The aim of this study was to assess the effect of parenteral iron administration on biomarkers of mineral and bone homeostasis over time. MATERIALS AND METHODS: The study was a single-centre non-randomised prospective study. It was carried out between 2016 and 2020 in a group of patients in the Department of Internal Medicine and Gastroenterology Subunit of Inflammatory Bowel Diseases at the National Institute of Medicine of the Ministry of the Interior and Administration in Warsaw. At the first examination, the baseline disease severity, initial evaluation of anaemia (morphology, iron (Fe), total iron binding capacity (TIBC), ferritin, vitamin B12, folic acid) and bone mineral metabolism including C-reactive protein (CRP), albumins, alkaline phosphatase (ALP), Calcium, osteocalcin, phosphate in serum and in urine, parathyroid hormone (PTH), vitamin D3, fibroblast growth factor (iFGF23) and procollagen type 1N propeptide (P1NP) C-terminal telopeptide (CTX), was initially assessed. On the basis of peripheral blood counts, an appropriate dose of iron (iron derisomaltose or caboxymaltose) was administered. During the subsequent appointments on week 1, 4, and 12 morphology, iron (Fe), total iron binding capacity (TIBC), ferritin, vitamin B12, folic acid, C-reactive protein (CRP), albumins, alkaline phosphatase (ALP), Calcium, osteocalcin, phosphate in serum and in urine, parathyroid hormone (PTH), vitamin D3, fibroblast growth factor (iFGF23) and procollagen type 1N propeptide (P1NP) C-terminal telopeptide (CTX), were evaluated. RESULTS: A total of 56 patients were enrolled into the study: 24 women and 32 men. In the group, 32 patients had Crohn's disease (CD) and 24 had ulcerative colitis (UC). We found a statistically significant increase in the concentration of albumin (p = 0.031), haemoglobin (p < 0.001), haematocrit (p < 0.001), MCV (p < 0.001), MCHC (p = 0.001), iron (p < 0.001) and ferritin (p < 0.001) after the administration of parenteral iron. The influence of individual iron formulations on the analysed parameters (phosphate concentration in serum and in the urine, iFGF23, P1NP, PTH, vitamin D, haemoglobin and ferritin) was similar. Interestingly, an inverse correlation was found between the concentration of phosphorus in the blood and iFGF23 at certain time-points; however, in the study group they did not significantly affect the disturbances of calcium and phosphate metabolism. CONCLUSIONS: In the study group, transient and non-significant disorders of phosphate metabolism were found, which does not constitute a contraindication to treatment with parenteral iron in inflammatory bowel disease patients, which was safe and efficient.

Early changes in serum creatinine level and estimated glomerular filtration rate predict pancreatic necrosis and mortality in acute pancreatitis: Creatinine and eGFR in acute pancreatitis.

AIM: The aim of the study was to evaluate the significance of serum creatinine level (SCL) and estimated glomerular filtration rate (eGFR) measured in an early phase of acute pancreatitis (AP) for prediction of pancreatic necrosis (PNec) and mortality. METHODS: One hundred and forty-seven patients with AP were retrospectively reviewed in the study. Serum creatinine level and estimated glomerular filtration rate (calculated using the abbreviated Modification of Diet in Renal Disease equation) on admission and 48 h thereafter were analyzed for each patient. These parameters were compared with contrast-enhanced computed tomography images performed within 96 h from admission (n = 103). Usefulness of SCL and eGFR for prediction of PNec and fatal outcome of AP was evaluated using a receiver operator characteristic curve analysis and comparison of average parameter values. RESULTS: We confirmed pancreatic necrosis in 41 (39.8%) of 103 patients using computed tomography examination. Both creatinine and estimated glomerular filtration rate measured on admission (p < 0.001, p < 0.001 respectively) and 48 h later (p = 0.001, p < 0.001 respectively) were significantly associated with the presence of pancreatic necrosis. Moreover, serum creatinine level and eGFR measured on the 1st day proved to be a good predictor of fatal outcome. Both, mortality and presence of pancreatic necrosis were significantly higher in the group with elevated serum creatinine level and low eGFR values. CONCLUSIONS: SCL and eGFR on admission are useful indicators of PNec and mortality.

Diffuse nodular lymphoid hyperplasia of the gastrointestinal tract in patient with selective immunoglobulin A deficiency and sarcoid-like syndrome--case report.

Nodular lymphoid hyperplasia is uncommon in adult patients. Associated diseases are common variable immunodeficiency (CVI) and lymphoid tissue malignancies. In this case report we focus on clinical presentation and differential diagnosis of diffuse nodular lymphoid hyperplasia of the gastrointestinal tract coexisting with selective immunoglobulin A deficiency and sarcoid-like syndrome.

Magnification chromoendoscopy in comparison to standard chromoendoscopy for detection of intestinal metaplasia in renal transplant recipients.

PURPOSE: Renal transplantation is associated with frequent gastrointestinal complications. Intestinal metaplasia is a feature of atrophic gastritis whereas the diagnosis of Barrett's esophagus is based on histological demonstration of specialized metaplasia. Both conditions are associated with increased risk of adenocarcinoma. The aim of the present study was to assess whether magnification endoscopy improves the diagnostic accuracy of intestinal metaplasia in stomach and in esophagus. MATERIAL AND METHODS: In this non-randomized, feasibility study thirty one (12 women and 19 men) renal transplant recipients, with a mean age of 44.0 years were evaluated for the presence of intestinal metaplasia. Standard esophagogastroscopy with methylene blue staining was followed by magnification endoscopy. The presence of gastritis and intestinal metaplasia was classified according to modified updated Sydney classification. RESULTS: Of 31 patients, 16 patients had endoscopic and histopathological evidence of gastric intestinal metaplasia, and standard endoscopy with methylene blue staining was sufficient for diagnosis (15 from 16). Magnification endoscopy allowed identification of 6 patients with specialized intestinal metaplasia in Barrett's esophagus, which would be otherwise missed. CONCLUSIONS: In this study diagnostic accuracy of standard endoscopy for identification of intestinal metaplasia in the stomach was not improved by the use of magnification endoscopy, but the latter was an accurate method of predicting specialized intestinal metaplasia in Barrett's esophagus. The use of magnification endoscopy in the clinical setting of renal transplantation needs further studies.

Gastric juice ammonia and urea concentrations and their relation to gastric mucosa injury in patients maintained on chronic hemodialysis.

PURPOSE: This study was undertaken to test the hypothesis that high concentrations of urea in gastric juice would have an influence on Helicobacter pylori infection in patients maintained on chronic hemodialysis (HD). MATERIAL AND METHODS: We investigated 30 patients (17 males, 13 females; mean age 50.8 +/- 2.9 years) with end-stage renal disease (ESRD) undergoing hemodialysis treatment (HD) for at least 6 months, who were compared to 31 patients (16 males, 15 females; mean age 61.3 +/- 2.2 years) with dyspeptic symptoms. Biopsies from the gastric antrum and body were taken for histological investigation. Urea and ammonia were measured in gastric juice, and the severity of gastritis was evaluated according to Sydney criteria. RESULTS: H. pylori infection was found in 19 (63%) HD patients and in 22 (71%) control subjects. Gastric juice urea concentration was significantly higher in HD patients than in controls and H. pylori infection caused a significant decrease in urea concentration in both groups. There was an inverse correlation between urea and ammonia concentration in gastric juice in both groups. Ammonia concentration in both groups was higher in H. pylori infected patients. In H. pylori negative subjects ammonia/urea ratio was lower in HD patients in comparison to controls. Ammonia/urea ratio was raised by H. pylori infection in both groups, and the difference between HD and control groups persisted. H. pylori infection was associated with polymorphonuclear infiltration of gastric mucosa. There was a significant correlation between gastric ammonia and mucosal polymorphonuclear leukocytes infiltration and gastritis score. CONCLUSIONS: Higher urea levels in the gastric juice of chronically hemodialyzed patients do not seem to be a risk factor for infection with Helicobacter pylori.

Does chronic ethanol administration have influence on pancreatic regeneration in the course of caerulein induced acute pancreatitis in rats.

UNLABELLED: This study was undertaken in order to determine the influence of chronic ethanol administration on pancreatic regeneration during acute pancreatitis (AP). Rats were pair fed with isocaloric diet containing or not ethanol. After 8 weeks of such feeding AP was induced by s.c. injection of caerulein (Cae). 6 h, 24 h and 5 days after first Cae dose pancreatic weight, amylase, chymotrypsin, protein, RNA, DNA contents were determined and phosphatidic acid (PA) production in isolated pancreatic acini was measured. Proliferating cells were quantified by immunochemical staining of cells incorporating bromodeoxyuridine (BrdU). RESULTS: Pancreatic weight was significantly higher at 6 h after first Cae injection in both, ethanol fed (EF) and control groups (C), however at 24 h pancreatic weight did not differ from prior to AP induction in EF rats. Ethanol feeding (EF) did not influence significantly protein, chymotrypsin and amylase content in pancreatic tissue in groups with AP. In EF rats RNA content after 5 days of AP was higher than in control animals. Total DNA content in EF rats with AP was lower 6 h after AP induction, earlier than in control animals with AP. Immunochemistry showed higher labelling index for BrdU after 6 h, 24 h and 5 days of AP in EF rats. In contrast to this findings, in EF animals, AP induction was not able to stimulate further PA accumulation. CONCLUSION: We conclude that chronic ethanol feeding, while inhibiting PA accumulation in comparison to control group, does not impair pancreatic tissue regeneration during the early phase of Cae-induced AP. Stimulation of regenerative/reparative processes in EF rats during Cae-induced AP seems to be even more pronounced than in the control group.

The role of nitric oxide in caerulein-induced acute pancreatitis and the recovery process after inflammatory damage.

OBJECTIVES: Nitric oxide (NO) is involved in the control of pancreatic blood flow and secretion, and its role in the maintenance of pancreatic tissue has been suggested. The aim of our study was to evaluate the influence of NO on pancreatic trophic parameters during acute pancreatitis induction and the pancreas recovery process. DESIGN/METHODS: Acute pancreatitis was induced in rats by a supramaximal dose of caerulein. During acute pancreatitis induction, rats were treated with L-arginine (a substrate for NO synthesis), glyceryl trinitrate (NTG, NO donor), glycine, N(G)-nitro-L-arginine (L-NNA, NO synthase inhibitor), L-arginine + L-NNA, or saline. Pancreatic weight, total contents of RNA, DNA, protein, amylase and chymotrypsin as well as pancreas histology and the number of proliferating acinar cells were evaluated after pancreatitis induction in all groups and additionally after 7 and 14 days of recovery in untreated acute pancreatitis rats or those injected with L-NNA and/or L-arginine. RESULTS: Pancreas destruction after acute pancreatitis was evidenced by similar decreases of all parameters in untreated acute pancreatitis rats or those treated with L-NNA or glycine when compared to control healthy animals. The recovery process after acute pancreatitis was not affected by L-NNA injections; however, the increased cell proliferation occurred later than in untreated rats. NTG and especially L-arginine treatment resulted in significant attenuation of pancreas damage (partially prevented by L-NNA treatment) as evidenced by biochemical data with a slight improvement in morphology. Treatment with L-arginine alone or in combination with L-NNA resulted in augmented cell proliferation after acute pancreatitis induction followed by earlier recovery in comparison to untreated acute pancreatitis rats or the L-NNA-injected group. CONCLUSION: The present study suggests the involvement of NO in mild acute pancreatitis and in the recovery process after inflammatory damage.

Pancreatic regeneration after chronic ethanol feeding in rats.

UNLABELLED: Increase of phosphatidic acid (PA) accumulation in response to caerulein (Cae) and after subtotal pancreatectomy (SP) has been previously described and phospholipase D (PLD) derived PA involvement in pancreatic regeneration was suggested. We also described decrease of Cae stimulated PA accumulation after a single dose of ethanol (both in vitro and in vivo). The present study was undertaken in order to determine the influence of chronic ethanol feeding on basal and Cae stimulated PA accumulation and other parameters of pancreatic regeneration in control and ethanol feed rats. Male rats were pair fed ad libitum with an isocaloric liquid diet (Lieber De Carli) with or without ethanol. In vitro study: pair fed rats were killed after 2 or 6 weeks of feeding, pancreata were dissected out and weighted, dispersed pancreatic acini were then prepared and loaded with 3H myristic acid in order to label the phosphatidylcholine pool. Phosphatidic acid (3H PA) accumulation, in the presence of propranolol, was measured after stimulation with increasing doses of Cae. In vivo study: PA was measured 3 days after SP or sham operation in both groups of rats, and also after 1 h of Cae infusion (0.25 microg/kg/h). Pancreatic weight, amylase, protein, RNA and DNA content were established. RESULTS: In vitro study 1) Basal PLD activity expressed as PA accumulation was significantly elevated after 6 weeks of ethanol feeding in comparison to the control values (28%). 2) Cae in doses ranging from 100 pM to 5 nM was not able to stimulate PA accumulation in isolated pancreatic acini prepared from ethanol fed rats. In vivo study: 1) Body weight and pancreatic weight were similar in, both the ethanol fed and the control groups, after 2 and 6 weeks. 2) Ethanol feeding significantly decreased total amylase content in the pancreas, but did not change protein, RNA and DNA content. 3) in contrast to the control animals in which SP caused a 71.1% increase of PA accumulation over the sham operation, subtotal pancreatectomy was not able to stimulate PA in rats fed with ethanol. 4) Also Cae infusion did not stimulate PA accumulation in the ethanol fed animals in comparison to the controls. Since the involvement of PLD activation in the early stages of pancreatic regeneration was postulated, our results suggest that chronic ethanol feeding can influence this process by decrease of PA production, probably because of the inhibition of hydrolytic PLD activity in the presence of ethanol. This could be one of the mechanisms responsible for pancreatic injury after chronic ethanol consumption.

The influence of polyamines synthesis inhibition on pancreas regeneration and phospholipase D activity after acute caerulein induced pancreatitis in rats. Biochemical and ultrastructural study.

The importance of polyamines in tissue growth and regeneration was shown. The involvement of phospholipase D (PLD) activity in pancreas recovery after acute pancreatitis (AP) was postulated. Thus, the aim of present study was to evaluate: the effect of polyamines synthesis inhibition on pancreas regeneration after AP and possible relationship between polyamines metabolism and PLD activity during recovery after AP. AP was induced by s.c. injection of caerulein (Cae.) in gelatin (12 micrograms/kg; t.i.d.) during 2 days. After AP inducion rats were treated with the irreversible inhibitor of polyamines synthesis alpha-difluoromethylornithine (DFMO) and/or putrescine or saline for 2, 7 and 14 days. Pancreatic weight, total protein, enzymes, nucleic acids contents were evaluated and ultrastructural examination was performed. Also pancreatic acini were prepared and loaded with [3H] myristic acid to measure 3H phosphatidic acid (PA), a marker of PLD activity. For in vitro study the pancreatic acini from healthy rats were preincubated with 1 mM DFMO and stimulated with Cae. AP results in pancreas destruction, followed by spontaneous recovery within 14 days. We found that treatment with DFMO during AP induction did not produce more severe tissue damage. However, when this treatment was prolonged (up to 14 days) during the recovery period after pancreatitis injury reduced the spontaneous regeneration. Microscopic examination showed also the more prominent signs of acinar cell injury in AP-DFMO treated rats vs. AP animals especially after 7 and 14 days of treatment. The signs of microscopic injury, lower pancreatic weight and RNA content in acute pancreatitis rats treated with DFMO during 14 days vs. control group correspond with the increased PLD activity observed after 7 and 14 days of treatment. PLD activity increased significantly also in healthy rats treated with DFMO already after 2 days and remained at significantly elevated level after 7 and 14 days of treatment vs. control. The obtained results indicate the involvement of polyamines in pancreas recovery after acute pancreatitis and in unspecified pancreas injury with concomitant increase of PLD activity. However the modulation/elevation of enzyme activity does not seem to be directly related to polyamines metabolism in the pancreas as the lack of DFMO effect on PLD activity in vitro study was found. The results suggest rather indirect modulatory influence of polyamines on intracellular signaling pathway.

The effect of prostacyclin analogue--iloprost on the pancreas regeneration after caerulein-induced acute pancreatitis in rats.

UNLABELLED: Prostacyclin (PGI2) and its stable analogue iloprost (I) exert beneficial effect in acute pancreatitis (AP). The aim of the study was to evaluate the role of iloprost in pancreas regeneration after AP in rats. METHODS: AP was induced in male Wistar rats by s.c. injections of caerulein 12 micrograms/kg t.i.d. for 2 days. Rats were divided into four groups: control + saline (C); control + iloprost (C/I); AP + saline (AP); AP + I (AP/I). Rats were treated for 7 or 14 days. I (Schering AG) was given at the dose I microgram/kg b.w., i.p., t.i.d. After the rats were killed, the pancreata were weighed and their protein, DNA, RNA, chymotrypsin, alpha-amylase contents were evaluated. Light microscopic examination of representative pieces of pancreas was performed. RESULTS: Acute pancreatitis resulted in pancreas destruction observed even 7 days after the onset of the disease. The significant decrease of pancreatic weight, RNA and chymotrypsin contents were observed in AP rats when compared to C. The improvement of pancreatic histology and significant increase of DNA content were found in I treated (during 7 days) AP rats in comparison to untreated AP group. Two weeks after pancreatitis induction the pancreas regeneration occurred in both pancreatitis groups and it was connected with pancreas hypertrophy. Treatment with I resulted in slight not significant increase of some of cellular hypertrophy indices when compared to AP untreated animals. Healthy rats injected with I during 7 days showed significant elevation of DNA content in comparison to C. When treatment with I was prolonged up to 14 days such hyperplastic effect was not observed. Our results suggest, that treatment with iloprost exerts temporary hyperplastic influence on the pancreas of healthy rats and pancreas regenerating after caerulein-induced pancreatitis.

The influence of acute ethanol ingestion on phospholipase D activity in rat pancreas. An in vitro and in vivo study.

CONCLUSION: Since phosphatidic acid (PA), a product of phospholipase D(PLD), is known as a second messenger probably involved in cell proliferation and differentiation, our results potentially suggest a new mechanism for pancreatic tissue injury after ethanol ingestion. BACKGROUND: The mechanisms by which ethanol causes pancreatic injury are still not clear. In vitro studies have suggested a relationship of PLD to ethanol metabolism. This study was undertaken to establish the involvement of PLD in ethanol metabolism in isolated pancreatic acini and to determine the influence of acute ethanol ingestion on PLD activity in pancreas and pancreatic growth after cerulein (Ce) infusion. METHODS: Dispersed pancreatic acini prelabeled with 3H myristic acid were incubated with 500 pM Ce in the presence of different concentrations of ethanol; then labeled PA and phosphatidylethanol (PEt) production were measured under the same experimental conditions. For in vivo study, male rats were infused with Ce (0.25 microgram/kg/h) or saline; 1 h before infusion, animals were treated with 40% ethanol (5 g/kg p.o.) or saline, respectively. After 1, 2, and 48 h of Ce infusion, rats were killed; dispersed pancreatic acini were then prepared and PLD activity was measured. Pancreatic weight, protein, RNA, and DNA content were also established. RESULTS: The production of PEt in vitro after Ce stimulation was significantly elevated with 1% ethanol in the medium. In the presence of different concentrations of ethanol (0.5-2%), a significant inhibition of PA accumulation in in vitro experiments was observed. The decrease of PA accumulation with ethanol was parallel to the increase of PEt production under the same experimental conditions. PLD activity was significantly elevated after 1 and 2 h of Ce infusion (116 and 105%, respectively), reaching control value after 48 h. Acute ethanol ingestion significantly diminished PLD activity after 1 and 2 h. After 48 h of Ce infusion, a significant increase in pancreatic weight, protein, RNA, and DNA content in pancreatic tissue was found. Ethanol was not able to influence pancreatic weight, proteins and RNA content. However, it had the potency to diminish DNA content after 48 h of Ce infusion.

Phospholipase D mediated transphospatidylation as a possible new pathway of ethanol metabolism in isolated rat pancreatic acini.

Activation of pancreatic phospholipase D (PLD) has been previously observed in response to caerulein (Cae), phorbol myristate acetate and growth factors. Although PLD involvement has been postulated in pancreatic cell proliferation and differentiation, the physiological role of this enzyme in pancreatic cells still remains unclear. In the presence of ethanol, PLD catalysed transphosphatidylation reaction, forming phosphatidylethanol (PEt). This study was thus undertaken to determine the involvement of PLD in ethanol metabolism in isolated pancreatic acini and to show the potential physiological consequences of transphosphatidylation. Dispersed pancreatic acini prelabelled with 3H myristic acid were incubated with 500 pM Cae in the presence or absence of different concentrations of ethanol, and labelled phosphatidylethanol (3H PEt) production or phosphatidic acid (3H PA) accumulation were measured. The production of PEt after Cae stimulation in pancreatic acini was significant from 0.5% up to 4% of ethanol in the medium and was not dependent on increasing concentration of ethanol. Prolonged up to 2 h stimulation with Cae in the presence of 1% ethanol did not increase PEt production which was almost stable since 5 min of stimulation. In the presence of different concentrations of ethanol (1-4%), the significant inhibition of PA accumulation was obtained after Cae stimulation, similar to inhibition with a specific PLD inhibitor--wortmannin. These data indicate that Cae activated PLD in the presence of ethanol caused PEt production in pancreatic acini. During formation of PEt in pancreatic acinar cells significant and parallel inhibition of PA accumulation was observed. This indicates the relation of PLD activation in isolated pancreatic acini to ethanol metabolism. Ethanol can act as an inhibitor of PLD activity. Since PA, a product of PLD, is known as a second messenger probably involved in cell proliferation and differentiation, this may suggest a potentially new mechanism for pancreatic tissue injury after ethanol ingestion.

Novel model of integration of signaling pathways in rat pancreatic acinar cells.

Cholecystokinin (CCK) is the major pancreatic secretagogue and acinar cell mitogen. This study was performed to determine by which effector systems CCK regulates tyrosine kinases, phosphatidylinositol (PtdIns) 3-kinase, and phospholipase D (PLD) activities. Pancreatic acini loaded with [3H]myristic acid or [3H]inositol were used to assay PLD and PtdIns 3-kinase. G protein activation with NaF increased particulate and crude cytosolic tyrosine kinase and PLD activities. PLD activation was pertussis toxin sensitive. Inhibition of phospholipase C (PLC) slightly reduced caerulein-stimulated particulate tyrosine kinase and blocked crude cytosolic tyrosine kinase activity without affecting caerulein-induced PLD activity. Ca2+ is an important factor in caerulein stimulation of tyrosine kinase and PLD activities. Protein kinase C and tyrosine kinase inhibition abolished caerulein-activated particulate and crude cytosolic tyrosine kinase and PtdIns 3-kinase activities without any effect on PLD. Wortmannin inhibited PLD and PtdIns 3-kinase activation. Caerulein-induced amylase secretion was partially reduced by tyrosine kinase inhibition, with no effect from wortmannin. Caerulein can stimulate a pertussis toxin-insensitive G protein, leading to particulate tyrosine kinase activation and a Ca(2+)-sensitive cytosolic tyrosine kinase through PLC activation. However, PLD activation by caerulein is pertussis toxin sensitive, cytosolic Ca2+ sensitive, and independent of previous PLC and tyrosine kinase activation.

Dynamics of pancreatic tyrosine kinase and phospholipase D activities in the course of cerulein-induced acute pancreatitis and during regeneration.

Acute pancreatitis can be induced in the rat by high doses of cerulein, a cholecystokinin analogue. Regeneration of the pancreatic gland after this aggression can be accelerated by endogenous or exogenous cholecystokinin. However, the biochemical and molecular events associated with the cholecystokinin-induced regeneration process have not yet been identified. This study was therefore undertaken to determine the potential involvement of particulate and crude cytosolic tyrosine kinases as well as phospholipase D (PLD) in the course of pancreatitis induction and during regeneration. Acute pancreatitis was induced by cerulein, 12 micrograms kg-1, every 8 h for 2 days; this treatment was followed by 3 days of rest, and the regeneration treatment was started on the morning of the sixth day, with cerulein given at 1 microgram kg-1 every 8 h for 1-4 days. Animals were sacrificed 1, 3, 6, 12, 24, and 48 h after the first cerulein injection (high dose), on the morning of the sixth day (end of the rest period), and on the morning of the seventh and tenth days (low dose, regeneration period). After sacrifice, pancreata were excised and prepared for tyrosine kinase and PLD assays. Parallel increases in tyrosine kinase and PLD activities were observed from 6 to 48 h during pancreatitis induction and at the end of the resting period. Activities returned to control values during the regeneration period in the untreated cerulein-pancreatitis groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell signalling pathway involved in PACAP-induced AR4-2J cell proliferation.

The novel 38-amino acid neuropeptide PACAP (pituitary adenylate activating peptide) has recently been shown to induce the pancreatic acinar tumour AR4-2J cell growth. This growth promoting effect of PACAP was, however, independent of adenylate cyclase activation but suppressed by pertussis toxin and the somatostatin analog SMS 201-995. This study was undertaken to search for potential cell signalling pathways involved in the growth promoting effect of PACAP on AR4-2J cells. The AR4-2J cells were grown in Dulbecco's Modified Eagle's Medium containing 10% foetal calf serum. For studies on cell signalling pathways, all experiments were carried out on cells which have reached 50 to 75% confluency. At that point, they were transferred to serum free medium overnight with or without 1 microCi/ml myristic acid. The next morning, cells were harvested, washed and used for tyrosine kinase and phospholipase D (PLD) activities. For studies on growth, cells were grown for 2 days in the presence of 1 nM PACAP +/- the different inhibitors of tyrosine kinase and PLD. PACAP-38 and -27 caused a dose-dependent and parallel activation of tyrosine kinase and PLD an effect prevented by the antagonist PACAP 7-38. PACAP-38-stimulated tyrosine kinase and PLD activation are both dose-dependently inhibited by SMS 201-995. Finally, PACAP-stimulated tyrosine kinase and PLD activities are both inhibited by cell's preincubation with genistein and pertussis toxin. After 2 days, the PACAP-induced increase in AR4-2J cell growth was significantly inhibited by increasing concentrations of genistein and wortmannin, inhibitors of tyrosine kinase, PLD and phosphatidylinositol 3-kinase, respectively. PACAP can induce concomitant activation of tyrosine kinase and PLD; this finding and the observation that inhibition of these two enzymes inhibited PACAP-induced AR4-2J cell growth strongly suggests that they are intimately involved in the overall process of PACAP-induced AR4-2J cell proliferation.

Activation of pancreatic acinar cell phospholipase D by epidermal, insulin-like, and basic fibroblast growth factors involves tyrosine kinase.

The involvement of phospholipase D (PLD) in phosphatidylcholine hydrolysis by epidermal (EGF), insulin-like (IGF-I), and basic fibroblast (bFGF) growth factors was investigated in rat pancreatic acini. Acini were prelabeled with [3H]myristic acid which is mostly incorporated into phosphatidylcholine. EGF, IGF-I, and bFGF caused significant and dose-dependent increases in [3H]phosphatidic acid (PA) accumulation in the presence of propranolol, a phosphatidic acid phosphohydrolase inhibitor. The effects of EGF and IGF-I were significant after 5, 15, and 30 min of stimulation, whereas that of bFGF was evident only at 30 min. PA production in response to all three factors was dose dependent with maximal responses to EGF at 25 nM, to IGF-I at 16.5 nM, and to bFGF at 50 pM. Preincubation of acini with staurosporine, a protein kinase C and tyrosine kinase inhibitor, totally inhibited PA production by the three factors. Similarly, acini preincubation with genistein, a specific tyrosine kinase inhibitor, also neutralized the influence of the three factors on PA accumulation. In the presence of 1% ethanol, EGF, IGF-I, and bFGF caused significant phosphatidylethanol production after 20 min of incubation, thus confirming the involvement of PLD in PA production. These data present for the first time the description of a new signaling pathway through which EGF, IGF-I, and bFGF may operate to induce some of their specific effects on the pancreas in association with these growth factor receptors' tyrosine kinase activity.

Specificity of phospholipase D activation by cholecystokinin and phorbol myristate acetate but not by carbamylcholine and A23187 in rat pancreatic acini.

The gastrointestinal hormone cholecystokinin and the muscarinic agonist carbamylcholine are involved in pancreatic enzyme secretion through phospholipase C activation and production of the second messengers inositol trisphosphate and diacylglycerol. However, cholecystokinin induces growth of the pancreas whereas carbamylcholine does not. This study investigated the possibility of a specific cellular signalling transduction system through which cholecystokinin may induce pancreatic growth. Rat pancreatic acini were preincubated with 3H choline or 3H myristic acid to label phosphatidylcholine. They were then stimulated by caerulein, phorbol myristate acetate, and carbamylcholine; choline and phosphocholine release as well as phosphatidic acid and phosphatidylethanol production were measured to establish phospholipase D (PLD) activation. Caerulein, phorbolester and carbamylcholine increased phosphocholine release. Choline release was induced early by caerulein and later by phorbolester but not by carbachol. PLD was activated by caerulein and phorbolester but not by carbamylcholine. Increased intracellular calcium by A23187 had no effect on PLD activation but its chelation by BAPTA prevented caerulein-induced PLD activation. In conclusion, PLD seems to be selectively activated by caerulein and phorbol ester by two different mechanisms which are insensitive to carbamylcholine. It is suggested that the PLD pathway might be the cellular signalling system leading to pancreatic growth.

[Evaluation of the effectiveness of the preparation Panzytrat 20,000 U in the substitute treatment of chronic pancreatitis]. / Ocena skutecznosci preparatu Panzytrat 20,000 j w leczeniu substytucyjnym przewleklego zapalenia trzustki.

Panzytrat 20,000 U produced by Knoll is a modern galenic form of active pancreatic enzymes in the form of microgranules with uniform enzymatic composition. The studies of the preparation effectiveness were carried out in 88 patients with diagnosed exocrine failure in the course of chronic pancreatitis. The patients were taking Panzytrat 20,000 for 4 weeks in doses 3 x 1 capsule with main meals. Control examinations were performed two and four weeks after starting the treatment, assessing the patients' condition on the basis of history taking and medical examination; taking into account weight gain, duration and intensity of pain and dyspeptic symptoms, frequency and character of defeacations and possible undesirable effects. In a group of 37 patients, BNT-PABA test was also performed before the treatment and after one capsule of Panzytrat. The treatment with Panzytrat 20,000 caused a statistically significant reduction of the number of defecations, significant reduction of pain and dyspeptic symptoms. A statistically significant increase of PABA recovery in urine was also obtained after one capsule of the preparation. Practically, no unfavourable effects of the treatment were observed. The studies carried out point to the high effectiveness of Panzytrat in dose 3 x 20,000. U daily in the treatment of exocrine pancreatic failure in the course of chronic pancreatitis.