Pathogenesis Of Chronic Pancreatitis Research Articles

Dietary Counseling Versus Dietary Supplements for Malnutrition in Chronic Pancreatitis: A Randomized Controlled Trial

Up to 50% of patients with chronic pancreatitis (CP) are malnourished. There are limited data on the role of dietary intervention in improving the nutritional status of such patients. The aim was to compare the efficacy of medium chain triglyceride (MCT)-enriched commercial dietary supplements with dietary counseling for homemade food in the management of malnutrition in patients with CP. In a randomized controlled trial, consecutive undernourished patients with CP (body mass index [BMI] <18.5 kg/m(2)) at a tertiary care hospital were randomized to receive either dietary counseling for regular homemade food or commercial MCT-enriched dietary supplements for a period of 3 months to compensate for the dietary calorie deficit. All patients received standard management for CP including pancreatic enzyme supplements. Primary outcome measure was improvement in BMI. Sixty malnourished patients with CP were randomized to counseling group (n = 29; mean age, 32 +/- 10 years; male, 83%) and supplementation group (n = 31; mean age, 28 +/- 10 years; male, 84%). BMI increased in both the counseling group and supplementation group (17.2 +/- 1.7 vs 18.1 +/- 1.8 kg/m(2), P = .001; 16.7 +/- 1.6 vs 18.2 +/- 1.6 kg/m(2), P = .001). There were similar improvements in triceps skinfold thickness, dietary intake, fecal fat, and pain score during a period of 3 months in both groups. There was, however, no significant difference between the counseling and supplementation groups with regard to any of the outcome measures. Dietary counseling for a balanced homemade diet is as good as commercial food supplements in improving malnutrition in patients with CP.

Pancreatic pain

Abdominal pain is an important clinical symptom in pancreatic diseases. There is increasing evidence that pain in chronic pancreatitis and pancreatic cancer is triggered by pancreatic neuropathy. Damage to intrapancreatic nerves seems to support the maintenance and exacerbation of neuropathic pain. In chronic pancreatitis, intrapancreatic nerves are invaded by immune cells. This observation led to the hypothesis that neuro-immune interactions play a role in the pathogenesis of chronic pancreatitis and the accompanying abdominal pain syndrome. Similarly, pancreatic cancer cells infiltrate the perineurium of local nerves, which may in part explain the severe pain experienced by the patients. Furthermore, perineural invasion extending into extrapancreatic nerves may preclude curative resection and thus often leads to local recurrence. In recent years, the involvement of a variety of neurotrophins and neuropeptides in the pathogenesis of pancreatic pain was discovered. This review summarises recent data on the mechanisms of neuropathy and pain generation in pancreatic disorders.

Altered anti-inflammatory response of mononuclear cells to neuropeptide PACAP is associated with deregulation of NF-κB in chronic pancreatitis

Although it is recognized that neurogenic influences contribute to progression of chronic inflammatory diseases, the molecular basis of neuroimmune interactions in the pathogenesis of chronic pancreatitis (CP) is not well defined. Here we report that responsiveness of peripheral blood mononuclear cells (PBMC) to the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) is altered in CP. Expression of PACAP and its receptors in human CP was analyzed with quantitative RT-PCR, laser-capture microdissection, and immunohistochemistry. Regulation of PACAP expression was studied in coculture systems using macrophages and acinar cells. Responsiveness of donor and CP PBMC to PACAP was determined based on cytokine profiles and NF-kappaB activation of LPS- or LPS+PACAP-exposed cells. Although donor and CP PBMC responded equally to LPS, PACAP-mediated counteraction of LPS-induced cytokine response was switched from inhibiting TNF-alpha to decreasing IL-1beta and increasing IL-10 secretion. The change of PACAP-mediated anti-inflammatory pattern was associated with altered activation of NF-kappaB: compared with LPS alone, a combination of LPS and PACAP had no effect on NF-kappaB p65 nuclear translocation in CP PBMC, whereas NF-kappaB was significantly decreased in donor PBMC. According to laser-capture microdissection and coculture experiments, PBMC also contributed to generation of a PACAP-rich intrapancreatic environment by upregulating PACAP expression in macrophages encountering apoptotic pancreatic acini. The nociceptive status of CP patients correlated with pancreatic PACAP levels and with IL-10 bias of PACAP-exposed CP PBMC. Thus the ability of PBMC to produce and to respond to PACAP might influence neuroimmune interactions that regulate pain and inflammation in CP.

Hydrogen Sulfide, Nitric Oxide and a Molecular Mass 66 u Substance in the Exhaled Breath of Chronic Pancreatitis Patients

Background/Aims: Human exhaled breath contains many molecules either present as gases or occurring in a soluble form in the vapor of the breath. This study was designed to evaluate the substances present in the exhaled breath of chronic pancreatitis (CP) patients. Subjects: Thirty-one consecutive CP patients (11 with exocrine insufficiency) and 31 healthy subjects (HS) were studied. Methods: Ninety-eight different substances were analyzed using a mass spectrometer on a breath sample from all subjects and on each respective ambient air sample. Results: H2S, NO and a substance having a molecular mass of 66 u (M66) were those which had significantly higher concentrations in CP patients than in HS after adjustment for the ambient air; the estimated increases attributable to the disease were 14% (p = 0.040) for H2S, 84% (p = 0.006) for M66 and 50% (p = 0.033) for NO, but the three volatile compounds showed poor diagnostic accuracy in differentiating CP patients from HS (AUC-ROC: 0.664, 0.715, and 0.602 for H2S, M66, and NO, respectively). Finally, no significant differences of H2S, M66, and NO were found between patients with and without alcoholic pancreatitis as well as between patients with and without pancreatic insufficiency. Conclusions: Exhaled breath analysis can rapidly and easily assess the presence of volatile compounds (H2S, NO and a substance having a molecular mass of 66 u) which may have properties capable of explaining, at least in part, the pathogenesis of CP.

Quantitative Proteomics Analysis Reveals That Proteins Differentially Expressed in Chronic Pancreatitis Are Also Frequently Involved in Pancreatic Cancer

The effective treatment of pancreatic cancer relies on the diagnosis of the disease at an early stage, a difficult challenge. One major obstacle in the development of diagnostic biomarkers of early pancreatic cancer has been the dual expression of potential biomarkers in both chronic pancreatitis and cancer. To better understand the limitations of potential protein biomarkers, we used ICAT technology and tandem mass spectrometry-based proteomics to systematically study protein expression in chronic pancreatitis. Among the 116 differentially expressed proteins identified in chronic pancreatitis, most biological processes were responses to wounding and inflammation, a finding consistent with the underlining inflammation and tissue repair associated with chronic pancreatitis. Furthermore 40% of the differentially expressed proteins identified in chronic pancreatitis have been implicated previously in pancreatic cancer, suggesting some commonality in protein expression between these two diseases. Biological network analysis further identified c-MYC as a common prominent regulatory protein in pancreatic cancer and chronic pancreatitis. Lastly five proteins were selected for validation by Western blot and immunohistochemistry. Annexin A2 and insulin-like growth factor-binding protein 2 were overexpressed in cancer but not in chronic pancreatitis, making them promising biomarker candidates for pancreatic cancer. In addition, our study validated that cathepsin D, integrin beta1, and plasminogen were overexpressed in both pancreatic cancer and chronic pancreatitis. The positive involvement of these proteins in chronic pancreatitis and pancreatic cancer will potentially lower the specificity of these proteins as biomarker candidates for pancreatic cancer. Altogether our study provides some insights into the molecular events in chronic pancreatitis that may lead to diverse strategies for diagnosis and treatment of these diseases.

Protective Effect of Natural Honey, Urtica diocia and Their Mixture against Oxidative Stress Caused by Chronic Ethanol Consumption.

Background: There is increasing implicating oxidative stress in the pathogenesis of chronic pancreatitis. The aim of this study is to investigate affect alcohol addiction and role of some protecting agent. Material and methods: Forty eight rats (Rattus norvigicus) were divided into 8 groups. Honey (2.5 g /kg b.w), Urtica dioica (250 mg/kg) and Alcohol orally administered at dose (20% exceeds by 2.5% weekly). Results: Ethanol feeding results in increasing serum glucose, total lipids, cholesterol, Low Density Lipoprotein (LDL), triglycerides, urea, liver Glucose-6-Phosphatase (G6Pase), pancreas and liver Malondialdehyde (MDA), Protein Carbonyl (PC). While a decrease were noted in serum insulin, High Density Lipoprotein (HDL), total Protein, Na, K, Ca, Mg, Cu, liver glycogen, pancreas and liver Glucose-6-Phosphate Dehydrogenase (G6PD), Glutathione- S-Transferase (GST), Reduced Glutathione (GSH), Catalase (CAT), Superoxide Dismutase (SOD). Conclusion: Administration of honey, urtica or both with alcohol prevent to great extent the lesions caused by only chronic alcohol administration. Consequently, honey and urtica administration are useful to minimize the hazardous effects resulting from ethanol abuse.

Chronic Pancreatitis: Challenges and Advances in Pathogenesis, Genetics, Diagnosis, and Therapy

Chronic pancreatitis (CP) is characterized by progressive pancreatic damage that eventually results in significant impairment of exocrine as well as endocrine functions of the gland. In Western societies, the commonest association of chronic pancreatitis is alcohol abuse. Our understanding of the pathogenesis of CP has improved in recent years, though important advances that have been made with respect to delineating the mechanisms responsible for the development of pancreatic fibrosis (a constant feature of CP) following repeated acute attacks of pancreatic necroinflammation (the necrosis-fibrosis concept). The pancreatic stellate cells (PSCs) are now established as key cells in fibrogenesis, particularly when activated either directly by toxic factors associated with pancreatitis (such as ethanol, its metabolites or oxidant stress) or by cytokines released during pancreatic necroinflammation. In recent years, research effort has also focused on the genetic abnormalities that may predispose to CP. Genes regulating trypsinogen activation/inactivation and cystic fibrosis transmembrane conductance regulator (CFTR) function have received particular attention. Mutations in these genes are now increasingly recognized for their potential 'disease modifier' role in distinct forms of CP including alcoholic, tropical, and idiopathic pancreatitis. Treatment of uncomplicated CP is usually conservative with the major aim being to effectively alleviate pain, maldigestion and diabetes, and consequently, to improve the patient's quality of life. Surgical and endoscopic interventions are reserved for complications such as pseudocysts, abscess, and malignancy.

Is genetic analysis helpful for diagnosing chronic pancreatitis in its early stage?

Diagnosis of chronic pancreatitis in its early stage is an extremely difficult task. If the genetic predispositions are identified, it may help make possible the earlier diagnosis of chronic pancreatitis or the detection of patients at risk. There are two major hypotheses about the pathogenesis of chronic pancreatitis known as the "necrosis-fibrosis" and "pancreatic stone protein" hypotheses. Recent molecular and genetic evidence suggests that both pathways contribute to the pathogenesis of chronic pancreatitis. Chronic pancreatitis may be caused by either increased proteolytic activity [the cationic trypsinogen (PRSS1) gene] or decreased protease inhibition (the pancreatic secretory trypsin inhibitor (PSTI) gene]. The impaired pancreatic duct function [cystic fibrosis transmembrane conductance regulator (CFTR) gene] may also be involved in the pathogenesis of the disease. Except for PRSS1 mutations, the known genetic risk for chronic pancreatitis is not high. The high individual variability and low incidence of chronic pancreatitis suggest that yet unidentified genetic and environmental factors are important. Further genetic analysis is necessary for understanding the pathogenesis of chronic pancreatitis, which may be helpful for the earlier diagnosis of the juvenile- or young-onset disease.

TRANSATLANTIC DIFFERENCES IN THE SURGICAL TREATMENT OF CHRONIC PANCREATITIS

Hypothesis: The indications for surgical resection and the operation chosen in chronic pancreatitis (CP) may vary in Europe vs. America. Methods: We compared the morphology and circumstances that precipitated surgical therapy in either a German or US centre for pancreatic surgery. Retrospective analysis compared the serum biochemical values, morphological parameters, and clinical indications in 93 consecutive patients. CT scans were evaluated for the AP diameter of the pancreatic head, pancreatic duct dilation, and obstruction of the bile duct or duodenum. Symptoms were categorized as objective gastric outlet obstruction, obstructive jaundice, and haemorrhage versus subjective chronic pain. Differences were evaluated by Chi square, Wilcoxon and Fisher's exact tests. Results: 48 consecutive patients were studied from the German and 45 from the US centre. The prevalence of diabetes, exocrine insufficiency and chronic pain were not significantly different. The average maximal AP diameter of the pancreatic head mass was significantly greater in the German group (4.81 vs. 1.69 cm; p < 0.001). Symptoms of gastric outlet obstruction (9/48 vs. 1/45; p = 0.016) and haemorrhage (7/48 vs. 0/45; p = 0.013) significantly correlated with the larger size pancreatic head ("mass") in the German group. Bile duct stenosis (8/47 vs. 12/43, p = 0.31) and suspicion of malignancy (5/47 vs. 11/43; p = 0.097) were comparable, but intractable chronic pain (14/47 vs. 29/43; p = 0.001) was the most frequent principal indication in the US. Pancreaticoduodenectomy was performed in most US cases (37/45), whereas in Germany the Frey or Beger duodenum-preserving pancreatic head resection was preferred in 24/41 cases. Lateral pancreaticojejunostomy (Puestow procedure) was chosen infrequently in both centres. Conclusion: The patient populations and indications for surgical treatment differed greatly between a German and a US pancreatic surgery centre. In the German patients complications of advanced CP were more prevalent, whereas chronic pain and the suspicion of malignancy were the dominant reasons for resection in the US. The morphologic and functional disparities contribute to differences in the choice of surgical technique and may reflect intrinsic differences in the patient populations or the pathogenesis of CP in the two countries.

Blood Antioxidant Status and Lipid Peroxidation in Patients with Chronic Pancreatitis

Purpose: The role of immune system in pathogenesis of chronic pancreatitis is unclear. The aim of this study was to establish the main determinants of plasma antioxidant potential in different types of chronic pancreatitis: alcoholic pancreatitis (ACP, N = 25), biliary pancreatitis (BCP, N = 37). Methods: We measured blood plasma levels of lipid peroxide oxidation and antioxidant defense: malondialdehyde (MD), hydroperoxide of lipids (HL); ceruloplasmine (CP) and myeloperoxidase (MPO). Measurements were performed by using colorimetric methods. Results: In comparison to healthy volunteers (HV, N = 18) the average concentration of plasma free-radical oxidation determinants (MD and HL) in both groups of chronic pancreatitis were significantly higher (by 45%-91%). Ceruloplasmine activity was higher (approximately 35%) in patients with alcoholic chronic pancreatitis, and lower (49%) in case of biliary chronic pancreatitis. MPO levels were lower in 2,5 and 2,1 times in case of alcoholic pancreatitis and biliary pancreatitis accordingly. Conclusions: Low levels of antioxidant defense in patients suffering from different types of chronic pancreatitis show the exhaustion of immune defense, high indices of blood plasma lipid peroxidation underline important role of immune system in pathogenesis of chronic pancreatitis and determine strategy of therapy.

Assessment of oxidative stress in chronic pancreatitis patients

To assess the levels of antioxidant capacity and oxidative damage in blood of chronic pancreatitis (CP) patients in comparison with those in healthy control subjects, by using several different analytical techniques. Thirty-five CP patients and 35 healthy control subjects were investigated prospectively with respect to plasma levels of thiols, ferric reducing ability of plasma (FRAP, i.e. antioxidant capacity), levels of protein carbonyls and thiobarbituric acid reactive substances (TBARS). Additionally, we evaluated the production of reactive oxygen species (ROS) in whole blood. The antioxidative thiols including cysteine, cysteinylglycine and glutathione were significantly lower in CP patients. In addition, the non-enzymatic antioxidant capacity was significantly lower in CP patients, which correlated with the amount of oxidative protein (protein carbonyls) and the extent of lipid damage (TBARS), both were significantly higher in CP patients. The ROS production in whole blood after stimulation with phorbol 12-myritate 13-acetaat, demonstrated a strong tendency to produce more ROS in CP patients. Oxidative stress may contribute to the pathogenesis of chronic pancreatitis by decreasing antioxidant capacity and increasing oxidative damage in CP patients may be a rationale for intervention with antioxidant therapy.

Three-Dimensional Structure of Peripheral Exocrine Gland in Rat Pancreas

The purpose of this study was to elucidate the 3-dimensional structure of the peripheral pancreatic exocrine gland. We observed serial sections of rat pancreatic tissue using a transmission electron microscope and traced the intercalated duct lumina, intra-acinar secretory canaliculi, intercalated duct cells or centroacinar cells, and basement membranes of acini onto a transparent sheet. These traced diagrams were reconstructed. The intra-acinar secretory canaliculus had branches but no anastomosis. The intercellular secretory canaliculus was extended from the central lumen through the space between the lateral surfaces of the acinar cells to the acinar base. Furthermore, the cytoplasmic process of each centroacinar cell was extended along the central lumen and connected to an intercalated duct cell; thus, centroacinar cells with the same structure as intercalated duct cells were not isolated from the intercalated duct cells. In this study, we elucidated the normal 3-dimensional structure of the peripheral pancreatic exocrine gland. To understand the pathogenesis of chronic pancreatitis, in the future we intend to examine the morphologic changes of pancreatic tissue during the onset and advancement of chronic pancreatitis using animal models.

Induced thrombospondin expression in the mouse pancreas during pancreatic injury

Chronic pancreatitis is a disease characterized by pancreatic fibrogenesis in response to sustained or repetitive injury. Pancreatic stellate cells (PSC) are interstitial cells that produce excessive extracellular matrix components during the process of fibrogenesis and therefore play a central role in the pathogenesis of chronic pancreatitis. Because the matricellular proteins thrombospondin-1 (TSP-1) and TSP-2 have a role in regulating fibrogenesis in other tissues, the expression of these major TSP isoforms in the whole pancreas was measured in a mouse model of repetitive pancreatic injury. Specifically, mice were treated with cerulein, 50 μg/kg/h × 6 h with treatments repeated once or twice every 48 h. Expression was also evaluated in cultured PSC. PSC were isolated by outgrowth from normal mouse pancreas and expression of TSP-1 and TSP-2 was evaluated after serum-activation. The mRNA transcripts for TSP-1 and TSP-2 were increased, 16-fold and 87-fold respectively, in the pancreas in response to repetitive injury. In cultured PSC, these transcripts were also increased in response to serum and increases in mRNA were reflected by the secretion of TSP-1 and TSP-2 proteins by PSC into culture media. In summary, PSC may be an important source of both TSP-1 and TSP-2 in the pancreas in response to injury. These modulators of fibrogenesis could play a role in the development of pancreatic fibrosis that characterizes chronic pancreatitis.

Differential and Synergistic Effects of Platelet-derived Growth Factor-BB and Transforming Growth Factor-??1 on Activated Pancreatic Stellate Cells

The cytokines platelet-derived growth factor (PDGF) and transforming growth factor (TGF)-beta1 are major factors influencing the transformation from the quiescent to the activated phenotype of pancreatic stellate cells (PSC), a process involved in the pathogenesis of chronic pancreatitis. Albeit much effort has been made to study the effects of PDGF and TGF-beta1 on PSCs, their interaction is still unclear, because these cytokines show both differential and synergistic effects as outlined by this study. Culture-activated PSCs of rats were treated with PDGF-BB and TGF-beta1. Subsequent changes of cell proliferation and migration were determined by cell counting, (+)-bromo-2'-deoxyuridine enzyme-linked immunosarbant assay (ELISA), and migration assay. Gene expression, synthesis of proteins, and activation of kinases were further studied by reverse transcription-polymerase chain reaction, real-time polymerase chain reaction, ELISA, and Western blot. PDGF-BB increased PSC proliferation and migration, accompanied by elevated expression of matrix metalloproteinases (MMP)-13 and MMP-3. The mRNA amount of procollagen alpha2(I), alpha-smooth muscle actin (alpha-SMA), tissue inhibitor of metalloproteinase (TIMP)-1, and TGF-beta1 was also increased by PDGF-BB. In contrast, PDGF-BB reduced collagen type I in culture medium and synthesis of alpha-SMA. Treatment of PSC with TGF-beta1 decreased proliferation, had no significant effect on migration and MMP expression, but increased expression and synthesis of procollagen alpha2(I) and alpha-SMA. Both cytokines induced phosphorylation of extracellular signal regulated kinase (ERK)-1/2 and p38, but only PDGF-BB activated the protein kinase B signaling pathway. PDGF-BB augments effects of TGF-beta1 on the mRNA level presumably because of up-regulation of TGF-beta1 synthesis and common signaling pathways of the 2 cytokines. However, at the protein level, PDGF-BB impairs typical TGF-beta1 effects such as increased synthesis of collagen (type I) and alpha-SMA. Moreover, PDGF-BB facilitates degradation of extracellular matrix proteins by enhancement of MMP synthesis, but MMP activity was probably limited because of elevated tissue inhibitor of metalloproteinase 1 expression.

A Proinflammatory, Antiapoptotic Phenotype Underlies the Susceptibility to Acute Pancreatitis in Cystic Fibrosis Transmembrane Regulator (−/−) Mice

A Proinflammatory, Antiapoptotic Phenotype Underlies the Susceptibility to Acute Pancreatitis in Cystic Fibrosis Transmembrane Regulator (−/−) Mice

Novel Antioxidant Ameliorates the Fibrosis and Inflammation of Cerulein-Induced Chronic Pancreatitis in a Mouse Model

Background/Aim: Oxygen free radicals (OFRs) mediate an important step in the initiation of experimental acute pancreatitis and several clinical findings suggested the possible contribution of OFRs to the pathogenesis of pancreatic fibrosis. So far, there are no studies which reporting potential role of OFRs in development of chronic pancreatitis with the prevention with antioxidants. This study was aimed to establish the mice model of chronic fibrosing pancreatitis and to prove the involvement of OFRs in chronic pancreatitis with fibrosis. Methods: Repeated intraperitoneal cerulein injection was performed to induce chronic pancreatitis in mice. Histological changes in the pancreas were examined, and markers for oxidative stress were measured in the pancreatic tissue and serum of the mice. DA-9601, a phytochemical possessing anti-inflammatory and antioxidative action, was given together with cerulein to the mice. Results: Repeated intraperitoneal injection of cerulein provoked significant severity of chronic fibrosing pancreatitis after 5 weeks. After treatment of DA-9601, the extents of pancreatic fibrosis were statistically significantly decreased in accordance with lessened pancreatic inflammations. The NF-ĸB binding activities were increased in chronic pancreatitis, which were significantly attenuated after DA-9601 treatment. The levels of myeloperoxidase and iNOS activities were also significantly decreased in DA-9601-treated group compared to the pancreatitis only group. Cytoprotective proteins such as heat shock protein-70 (HSP) and metallothionein were significantly increased in the DA-9601-treated group. DA-9601 decreased the expressions of α-SMA and type I collagen in cultured pancreatic stellate cells. Conclusions: Oxidative stress was principally involved in the pathogenesis of chronic pancreatitis with fibrosis.

Increased Central Memory T Cells in Patients with Chronic Pancreatitis

Background/Aims: A dysregulated immune response has been suggested to be important for the pathogenesis of chronic pancreatitis (CP). Formation of immunological memory is based on the differentiation of naïve T lymphocytes to memory T lymphocytes after exposure to antigens and specific cytokines. The aim of this study was to analyze peripheral blood mononuclear cells (PBMCs) in patients with CP for different T lymphocyte subsets including naïve and memory T cells. Methods: PBMCs from 9 patients who had undergone pancreatic resection due to CP, 9 CP patients who had not been resected and 9 healthy controls were analyzed by flow cytometry. Results: Patients with CP had a skewed distribution of T lymphocytes, with an increased level of CCR7+/CD45RA– central memory T lymphocytes compared to healthy controls. Nonresected CP patients and subjects who had undergone pancreatic resection due to CP had similar levels of central memory T lymphocytes. Conclusion: Our results indicate that the dysregulation of the immune system in chronic pancreatitis seems to persist even after removal of large parts of the local inflammatory site. We suggest that the increase of central memory T lymphocytes may be important for maintaining the inflammatory process in chronic pancreatitis.

Localization of the human hedgehog‐interacting protein (Hip) in the normal and diseased pancreas

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a poor prognosis. Previously, it has been shown that Indian hedgehog (Ihh) and its two signaling receptors patched (Ptc) and smoothened (Smo) are involved in the pathogenesis of chronic pancreatitis (CP) and PDAC. In the current study we analyzed the expression, distribution, and function of another component of this signaling pathway, the human hedgehog-interacting protein (Hip), in the normal pancreas, CP and PDAC utilizing real-time quantitative reverse transcription-polymerase chain reaction (QRT-PCR), immunohistochemistry, immunofluorescence, Hip siRNA transfection, cell growth assays, and cell cycle analysis. By QRT-PCR, Hip mRNA levels were fifteenfold and fourteenfold increased in CP (n = 22) and PDAC (n = 31) tissues, respectively, compared to normal pancreatic tissues (n=20) and correlated with glioma associated antigen (Gli1) but not Ptc or Protein kinase A (PKA) mRNA levels. Only SU-8686 and BxPC-3 pancreatic cancer cells expressed Hip mRNA, whereas expression was below the level of detection in the other six pancreatic cancer cell lines tested. As shown by immunohistochemistry, Hip was expressed in normal pancreatic tissues mainly in the cytoplasm of islet cells and in smooth muscle cells of blood vessels. In contrast, in CP and PDAC there was a different distribution and staining intensity within the islets. Moreover, Hip immunoreactivity was observed in the tubular complexes, PanIN 1-3 lesions, as well as in pancreatic cancer cells. Incubation of pancreatic cancer cell lines with recombinant Hip revealed a growth inhibitory effect in SU-8686 and Capan-1 pancreatic cancer cells and no effect on cell growth in the other tested cell lines. In addition, silencing of Hip expression using specific siRNA molecules increased the growth of SU-8686 cells. In conclusion, Hip is expressed in the normal pancreas, CP and PDAC tissues. The different pattern of Hip expression and abnormal localization in the diseased pancreas suggest that the enhanced activation of hedgehog signaling in CP and PDAC is-at least in part-due to the aberrant responsiveness and expression of Hip in these diseases.

In vivo characterization of developing chronic pancreatitis in rats

Despite numerous experimental and clinical investigations, there is no unifying concept on pathophysiology and pathogenesis of chronic pancreatitis. Defining the interplay between pancreatic microcirculation and parenchymal tissue, we will provide a basis for the better understanding of pancreatic fibrogenesis using in vivo high-resolution multifluorescence microscopy in dibutyltin chloride (DBTC)-exposed rats. Pancreatic microcirculation at days 3 and 7 after DBTC revealed leukocyte activation with a two-fold higher fraction of rolling cells and a nine- to 10-fold increase of cells firmly adherent to the endothelial lining, followed by subsequent transendothelial migration into tissue, as given by chloracetate esterase histology. In vivo staining of acinar tissue with bisbenzimide presented single cells exhibiting nuclear chromatin condensation and fragmentation. Apoptotic cell death was confirmed by immunohistochemical staining for active caspase-3 as well as by TUNEL analysis. Necrotic cells were found dispersed throughout the exocrine tissue under observation. Both modes of cell death were found highest in extent at days 3 and 7 with 15–20 cells/mm2, but progressively decreased below 10 cells/mm2 up to 28 days after DBTC. By means of in vivo microscopy yellow-green autofluorescent collagen deposits were found at day 7 and progressively increased up to ∼12% at day 28 after DBTC. Concomitantly, density of capillaries progressively decreased and capillaries failing to conduct blood flow became apparent. Present on-line analysis indicates an early inflammatory response with acinar cell death, most probably triggering progression of disease with collagen deposition, capillary rarefication and manifestation of perfusion failure. These temporal and spatial multiparameter measurements of the in vivo microenvironment provide new insights into the pathological processes of pancreatic fibrogenesis.

Pathogenesis of Chronic Pancreatitis: An Evidence-Based Review of Past Theories and Recent Developments

In the past several decades, four prominent theories of chronic pancreatitis pathogenesis have emerged: the toxic-metabolic theory, the oxidative stress hypothesis, the stone and duct obstruction theory, and the necrosis-fibrosis hypothesis. Although these traditional theories are formulated based on compelling scientific observations, substantial contradictory data also exist for each. Furthermore, the basic premises of some of these theories are directly contradictory. Because of the recent scientific progress in the underlying genetic, cellular, and molecular pathophysiology, there have been substantial advances in the understanding of chronic pancreatitis pathogenesis. This paper will provide an evidence-based review and critique of the traditional pathogenic theories, followed by a discussion of the new advances in pancreatic fibrogenesis. Moreover, we will discuss plausible pathogenic sequences applied to each of the known etiologies.