A short, eclectic history of exocrine pancreatic insufficiency and chronic pancreatitis

Influences of exocrine pancreatic insufficiency on nutrient digestibility, growth parameters as well as anatomical and histological morphology of the intestine in a juvenile pig model

In a pig model, pancreatic duct ligation (PL) leads to a complete loss of exocrine function, causing an exocrine pancreatic insufficiency (EPI) without affecting endocrine function, allowing research of clinical effects and therapy options. This study aimed to investigate effects of experimentally induced EPI in juvenile pigs on digestion and intestinal morphology. Eight female juvenile cross-bred pigs (BW 54.8 kg at the start of the study) were included. Three animals were considered as a control (CON group), and in five animals the ductus pancreaticus accessorius was ligated (PL group). During the 10-week trial period, body weight and body measurements were recorded regularly. At the end of the trial, gastrointestinal tract (GIT) was investigated macroscopically and histologically and weight and digesta samples of individual segments were obtained. The pigs in the CON showed a significantly higher apparent total tract digestibility of crude protein and crude fat (87.8 and 79.9%, respectively) compared to PL (52.4 and 16.6%, respectively). Significant differences were noted in relative weights of duodenum, jejunum and colon (with and without digesta) and also in absolute weights of jejunum and colon. The mean number of nuclei in the transverse section in stratum circulare were significantly higher in all intestinal segments in CON compared to PL. Overall, EPI results in impaired nutrient digestibility with a greater filling of the GIT with digesta. The elongation of the small intestine does not represent "stretching" of the intestine, but rather increased synthesis of intestinal tissue.

Methods of a New Chronic Pancreatitis and Spontaneous Pancreatic Cancer Mouse Model Using Retrograde Pancreatic Duct Injection of Dibutyltin Dichloride

The current study aimed to develop a new chronic pancreatitis and spontaneous pancreatic cancer model on C57/BL6 mouse through retrograde pancreatic duct injection of dibutyltin dichloride (DBTC) and explore its basic pathological changes as compared to the previous published chronic pancreatitis model through tail vein injection of DBTC with alcohol drinking. C57/BL6 mice were randomly divided into 3 groups: CG (control group; n = 15), VG (tail vein injection of DBTC (8 mg/kg) with 10% alcohol drinking group; n = 20), and PG (retrograde pancreatic duct injection of DBTC group (1 mg/kg); n = 30). Five mice in each group were sacrificed at a specific time point after the first treatment. The pathological section was observed. The activities of amylase, bilirubin, and hyaluronic acid in serum were determined. The expression of fibronectin, COL1A1, α-SMA, MMP-1, and TIMP-1 in the pancreas was assayed. Severe fibrosis of the pancreas with inflammatory cell infiltration could be observed on day 21 in the PG. In the VG, slight fibrosis of the pancreas with inflammatory cell infiltration was observed on day 28. There were significant differences in serum amylase, bilirubin, and hyaluronic acid levels between the PG and VG. The protein level of COL1A1 and α-SMA significantly increased in the PG. The mRNA expression of TIMP-1 is upregulated and the MMP-1 mRNA level is downregulated in the PG. Finally, typical neoplastic pathological change is significantly obvious in the PG. In conclusion, we established and validated a new chronic pancreatitis (CP) and spontaneous pancreatic cancer mouse model through retrograde injection of DBTC into the pancreatic duct. Previously reported mouse model through tail vein injection of DBTC with alcohol drinking could not cause obvious CP and neoplastic pathological change in mice.

Pancreatic enzyme replacement therapy in patients with exocrine pancreatic insufficiency due to chronic pancreatitis: a 1-year disease management study on symptom control and quality of life

OBJECTIVE

Exocrine pancreatic insufficiency (EPI) is frequent in patients with chronic pancreatitis (CP). This 1-year, prospective, multicenter, observational, disease management study aimed to assess symptom improvement and quality of life in patients with CP with EPI who were receiving pancreatic enzyme replacement.

METHODS

Patients with CP and chronic EPI were either assigned to cohort 1 that consisted of patients already taking pancreatin (Kreon; Abbott Arzneimittel GmbH, Hannover, Germany) or cohort 2 that consisted of patients with newly diagnosed EPI without prior pancreatic enzyme treatment. Symptoms were documented, and quality of life was assessed using the gastrointestinal quality of life index (GIQLI) at baseline, 6 months, and 1 year.

RESULTS

A total of 294 patients were evaluated (cohort 1, n = 206; cohort 2, n = 88). The proportion of patients experiencing gastrointestinal symptoms and recurrent pain after 1 year was significantly reduced in both cohorts (P < 0.001). The alleviation of symptoms was reflected in GIQLI score improvements at 1 year in both cohorts (P < 0.001), independent of CP severity and etiology. Improvements in GIQLI score were more pronounced in cohort 2 (P < 0.001).

CONCLUSIONS

Pancreatin demonstrated symptom relief and improvement in quality of life in patients with CP-related EPI in this disease management study.

Treatment options in painful chronic pancreatitis: a systematic review

BACKGROUND

Longlasting and unbearable pain is the most common and striking symptom of chronic pancreatitis. Accordingly, pain relief and improvement in patients' quality of life are the primary goals in the treatment of this disease. This systematic review aims to summarize the available data on treatment options.

METHODS

A systematic search of MEDLINE/PubMed and the Cochrane Library was performed according to the PRISMA statement for reporting systematic reviews and meta-analysis. The search was limited to randomized controlled trials and meta-analyses. Reference lists were then hand-searched for additional relevant titles. The results obtained were examined individually by two independent investigators for further selection and data extraction.

RESULTS

A total of 416 abstracts were reviewed, of which 367 were excluded because they were obviously irrelevant or represented overlapping studies. Consequently, 49 full-text articles were systematically reviewed.

CONCLUSIONS

First-line medical options include the provision of pain medication, adjunctive agents and pancreatic enzymes, and abstinence from alcohol and tobacco. If medical treatment fails, endoscopic treatment offers pain relief in the majority of patients in the short term. However, current data suggest that surgical treatment seems to be superior to endoscopic intervention because it is significantly more effective and, especially, lasts longer.

The impact of MFG-E8 in chronic pancreatitis: potential for future immunotherapy?

Background

The glycoprotein MFG-E8 mediates phagocytic clearance of apoptotic cells and influences the pathogenesis and progression of inflammatory diseases. MFG-E8 was shown to attenuate the progression of inflammation and to improve survival in septic rats. Accumulating evidence suggests an immunomodulatory link between MFG-E8 and the pro-inflammatory chemokine fractalkine, which may determine the severity of pain, fibrosis, and inflammation in chronic pancreatitis (CP).

Methods

The expression and localization of MFG-E8 was investigated in CP (n = 62), and normal pancreas (NP; n = 34) by QRT-PCR, Western-blot and immunohistochemistry analyses. Results were correlated with mRNA expression of fractalkine, CX3CR1, and with the presence and degree of pain and fibrosis. Human pancreatic stellate cells (hPSCs) were isolated from CP tissues and evaluated for MFG-E8 mRNA expression after fractalkine stimulation.

Results

MFG-E8-mRNA was significantly overexpressed in CP and isolated hPSCs when compared to NP. Western-blot and immunohistochemistry analysis confirmed accumulation of MFG-E8 in CP, with noticeably increased MFG-E8 immunoreactivity in tubular complexes. MFG-E8 expression correlated significantly with fractalkine expression, severe fibrosis, and the presence of pain in CP patients. Stimulation of hPSCs with fractalkine led to a significant increase in MFG-E8 expression.

Conclusions

In the present study, we demonstrated for the first time that MFG-E8 is significantly up-regulated in CP patients and together with fractalkine correlated noticeably with severe fibrosis and the presence of pain. hPSCs overexpress MFG-E8 upon fractalkine stimulation in vitro, which underlines the suggested immunmodulatory link in CP and may be a key mechanism in CP fibrogenesis and pain generation. Taken together, these novel findings suggest that MFG-E8 blockade may be a promising tool for future immunotherapy in CP to attenuate both fibrosis and pain sensation.

Patients with exocrine insufficiency due to chronic pancreatitis are undertreated: a Dutch national survey

BACKGROUND

Treating exocrine pancreatic insufficiency with pancreatic enzymes is challenging because there is no fixed dose regimen. The required dose varies per patient, depending on the residual pancreatic function, the gut lumen physiology, and the fat content of each meal. Using a sufficient dose of enzymes is crucial to prevent weight loss, nutritional deficiencies, and to ameliorate steatorrhea-related symptoms. Data regarding the practise of enzyme replacement therapy are lacking. Therefore, we evaluated if patients with exocrine insufficiency caused by chronic pancreatitis receive proper treatment in the Netherlands.

METHODS

An anonymous survey was distributed to the members of the Dutch Association of Patients with Pancreatic Disorders. The survey focused on enzyme use, steatorrhea-related symptoms, dietary consultation, and food restrictions. Responding patients were included if they had chronic pancreatitis and were treated for exocrine insufficiency with pancreatic enzymes.

RESULTS

The survey was returned by 178 members who suffered from chronic pancreatitis, 161 of whom (90%) met the inclusion criteria. The mean age was 56 years and 53% were male. The median enzyme intake was 6 capsules per day and 25% of patients took 3 or less capsules. Remarkably, 70% of patients still reported steatorrhea-related symptoms, despite treatment. Only 25% of cases were referred to a dietician and 58% kept a restriction of fat (either instructed by a dietician or self-imposed).

CONCLUSION

Many patients with exocrine insufficiency caused by chronic pancreatitis are under-treated in the Netherlands, a country with a well-organized healthcare system. To improve treatment efficacy, patients should be educated in adjusting the enzyme dosage according to steatorrhea-related symptoms and dietary fat intake. Moreover, patients should be referred to a well-trained, specialized dietician.

Pancreatic enzyme replacement therapy in chronic pancreatitis

Exocrine pancreatic insufficiency (EPI) is a serious condition which occurs in several diseases including chronic pancreatitis (CP), cystic fibrosis, pancreatic cancer, and as a result of pancreatic surgery. The lack or absence of pancreatic enzymes leads to an inadequate absorption of fat, proteins, and carbohydrates, causing steatorrhoea and creathorrhea which results in abdominal discomfort, weight loss, and nutritional deficiencies. To avoid malnutrition related morbidity and mortality, it is pivotal to commence pancreatic enzyme replacement therapy (PERT) as soon as EPI is diagnosed. Factors as early acidic inactivation of ingested enzymes, under dosage, and patient incompliance may prevent normalisation of nutrient absorption, in particular of fat digestion. This review focuses on the current status of how to diagnose and treat EPI.

Properties of different pancreatin preparations used in pancreatic exocrine insufficiency

BACKGROUND

Pancreatic enzyme preparations are a life-saving substitution for a pivotal physiological function of the entire organism that is impaired in chronic pancreatitis, cystic fibrosis and other diseases with exocrine pancreatic insufficiency. Pancreatic enzyme preparations, generically called pancreatin, are not alike. Rather, they present a broad variety of pancreatin composition.

AIM

The properties of a set of commercially available pancreatin preparations were investigated in light of the physiological tasks such enzymes must fulfill during the normal digestive process.

METHODS

Measurements of size, surface, acid resistance, release of enzymes, pharmacokinetics and batch consistency were undertaken.

RESULTS

Although all pancreatin preparations contain the declared lipase units and are acid-stable, a wide variation was observed in the particle size (pyloric passage), specific surface area and release kinetics of lipase activity at pH 6 (duodenum).

CONCLUSION

At present, available pancreatin preparations vary widely with respect to investigated parameters, which may have consequences for facilitating optimal digestion.

Neural fractalkine expression is closely linked to pain and pancreatic neuritis in human chronic pancreatitis

The chemokine fractalkine induces migration of inflammatory cells into inflamed tissues, thereby aggravating inflammatory tissue damage and fibrosis. Furthermore, fractalkine increases neuropathic pain through glial activation, which can be diminished by blocking of its receptor, CX3CR1, through neutralizing antibodies. As chronic pancreatitis (CP) is characterized by tissue infiltration of inflammatory cells, fibrosis, pancreatic neuritis and severe pain, the roles of fractalkine and CX3CR1 were investigated in CP (n=61) and normal pancreas (NP, n=21) by QRT-PCR, western blot and immunohistochemistry analyses. Their expression correlated with the severity of pancreatic neuritis, fibrosis, intrapancreatic nerve fiber density and hypertrophy, pain, CP duration and with the amount of inflammatory cell infiltrate immuno-positive for CD45 and CD68. To investigate the influence of fractalkine on pancreatic fibrogenesis, human pancreatic stellate cells (hPSCs) were isolated from patients with CP, incubated with fractalkine and then Collagen-1 and alpha-smooth muscle actin (alpha-SMA) expressions were measured. CX3CR1, but not fractalkine, mRNA was overexpressed in CP. In contrast, the protein levels of both CX3CR1 and fractalkine were upregulated. Neuro-immunoreactivity for fractalkine and CX3CR1 was strongest in patients suffering from severe pain and pancreatic neuritis. Long-term suffering from CP was noticeably related to increased neural immunoreactivity of fractalkine. Furthermore, fractalkine and CX3CR1 mRNA overexpressions were associated with enhanced lymphocyte and macrophage infiltration. Advanced fibrosis was associated with increased fractalkine expression, whereas in vitro fractalkine had no significant impact on collagen-1 and alpha-SMA expressions in hPSCs. Therefore, pancreatic fractalkine expression appears to be linked to visceral pain and to the recruitment of inflammatory cells into the pancreatic tissue and nerve fibers, with subsequent pancreatic neuritis. However, pancreatic fibrogenesis is probably indirectly influenced by fractalkine. Taken together, these novel findings suggest that CX3CR1 represents a potential novel therapeutic target to reduce inflammation and modulate pain in CP.

The effectiveness of enzymatic replacement therapy measured by turbidimetry and the lipaemic index in exocrine pancreatic insufficient young, growing pigs, fed a high-fat diet

PURPOSE

Conventionally, the management of exocrine pancreatic insufficiency (EPI) involves the consumption of a specific diet as well as the replacement of pancreatic enzymes, the effectiveness of which is usually measured by a classical method of blood analyses of non-esterified fatty acids (NEFA) and triglycerides (TG). Dietary supplementation with a pancreatic enzyme preparation (PEP), in conjunction with a high-fat diet, on growth performance, digestibility and absorption (analysed using turbidimetry) of dietary fat in pigs with EPI was investigated.

MATERIALS/METHODS

EPI was developed by surgical ligation of the pancreatic duct of six male pigs, 6 weeks of age. The pigs were fed a high fat diet (twice daily). A PEP containing 1800 mg entero-coated pancreatin was included in the high fat meals. Blood, urine and faecal samples were collected. The urine and faeces were analysed for dry matter, crude protein and fat content. The lipaemic index and plasma lipid profiles were assessed.

RESULTS

EPI completely stopped growth of the pigs. Treatment with PEP significantly increased (P<0.05) growth and body mass as well as the digestibility of dry matter and crude protein. PEP significantly improved the co-efficient of fat absorption, the lipaemic index (measured by turbidimetry methods) and caused significant changes in plasma nonesterified fatty acids and triglyceride concentrations.

CONCLUSIONS

The short term enzymatic replacement therapy together with a high fat meal has immediate beneficial effects on diet digestibility and on the growth retardation observed in EPI pigs. The turbidimetry method used to measure lipaemic index is a reliable, quick and efficient technique in measuring plasma lipid profiles and thus a good tool for assessing fat absorption.

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.

Management of pain in small duct chronic pancreatitis

Small duct chronic pancreatitis (CP) is defined by a nondilated main pancreatic duct, and the morphological and clinical features of chronic pancreatitis with pain are the most prominent symptoms. Current treatment strategies are based on pain history and the location and extent of disease. Traditionally, radical pancreatic resectional procedures have been carried out for small duct CP, especially with an associated head mass of uncertain aetiology. Based on the information from five randomized trials, the duodenum-preserving pancreatic head resection and its modifications have proven to provide excellent long-term pain relief and to be superior to more radical operations. Therefore, these procedures can be considered the standard for small duct CP with head dominant disease. The longitudinal V-shaped excision of the ventral pancreas combines extensive drainage and a limited resection and offers good pain relief in diffuse small duct CP. However, long-term results and larger series are awaited for definite conclusions. Thoracoscopic splanchnicectomy and endosonography-guided celiac plexus blocks require controlled trials before their routine use. This article provides an overview about the current and evidence-based pain management in small duct CP.

Serum lipase activities and pancreatic lipase immunoreactivity concentrations in dogs with exocrine pancreatic insufficiency

OBJECTIVE

To determine serum lipase activities and pancreatic lipase immunoreactivity (PLI) concentrations in dogs with exocrine pancreatic insufficiency (EPI).

ANIMALS

74 healthy dogs and 25 dogs with EPI.

PROCEDURES

A diagnosis of EPI was made on the basis of clinical signs, low serum trypsin like immunoreactivity (TLI) concentration, and response to treatment with enzyme replacement. Median values for fasting serum lipase activity and serum PLI concentrations were compared between the 2 groups with a Mann-Whitney U test.

RESULTS

Median fasting serum lipase activity was not significantly different between dogs with EPI (366.0 U/L) and healthy dogs (294.5 U/L), and only 1 dog with EPI had a serum lipase activity less than the lower limit of the reference range. Median serum PLI concentration was significantly lower in dogs with EPI (0.1 microg/L) than in healthy dogs (16.3 microg/L). All dogs with EPI had serum PLI concentrations less than the lower limit of the reference range.

CONCLUSION AND CLINICAL RELEVANCE

Serum lipase activity is not limited to the exocrine pancreas in origin, whereas serum PLI is derived only from the exocrine pancreas. Unlike in serum TLI concentrations, there was a small degree of overlap in serum PLI concentrations between healthy dogs and dogs with EPI. Serum TLI concentration remains the test of choice for diagnosis of EPI.

Immortalization of pancreatic stellate cells as an in vitro model of pancreatic fibrosis: deactivation is induced by matrigel and N-acetylcysteine

Tissue fibrosis is one of the characteristics of chronic pancreatitis and pancreatic adenocarcinoma. Activated pancreatic stellate cells (PSC) play a central role in this process. However, analysis of the molecular mechanisms leading to PSC activation is hampered by the lack of an established human PSC line. To overcome this problem, we immortalized and characterized primary human PSC. The cells were isolated by the outgrowth method and were immortalized by transfection with SV40 large T antigen and human telomerase (hTERT). Primary human PSC served as controls. An immortalized line, RLT-PSC, was analyzed for the expression of stellate cell markers. Moreover, the effects of transforming growth factor beta 1(TGFbeta1) or platelet-derived growth factor stimulation and of cultivation on basement membrane components or N-acetylcysteine (NAC) treatment on gene and protein expression and proliferation were analyzed. Immortal RLT-PSC cells retained the phenotype of activated PSC proven by the expression of alpha-smooth muscle actin (alphaSMA), vimentin, desmin and glial fibrillary acidic protein (GFAP). TGFbeta1 treatment upregulated the expression of alphaSMA, collagen type I (Col I), fibronectin and TGFbeta1. Incubation of RLT-PSC cells and primary human activated PSC on Matrigel plus NAC treatment resulted in a deactivated phenotype as evidenced by a decrease of alphaSMA, connective tissue growth factor and Col I expression and by a decreased proliferation of the cells. Moreover, this treatment restored the ability of the cells to store vitamin A in cytoplasmic vesicles. In conclusion, we have established an immortal pancreatic stellate cell line, without changing the characteristic phenotype. Importantly, we were able to demonstrate that besides soluble factors, the matrix surrounding PSC plays a pivotal role in the maintenance of the activation process of PSC. Cultivation of activated PSC on a reconstituted basement membrane plus treatment with NAC was able to deactivate the cells, thus pointing to the possibility of an antifibrosis therapy in chronic pancreatitis.

Comparison of histological features and inflammatory cell reaction in alcoholic, idiopathic and tropical chronic pancreatitis

BACKGROUND

There is increasing evidence that immune mechanisms may be crucial in the development of alcoholic chronic pancreatitis. However, it is not known whether differences in underlying aetiology influence the inflammatory reaction in patients with chronic pancreatitis. The histological features and the pattern of inflammatory cell infiltration were studied in three aetiological forms of chronic pancreatitis: alcoholic, idiopathic and tropical pancreatitis.

METHODS

Forty-three patients, ten with alcoholic, 12 with idiopathic and 21 with tropical chronic pancreatitis, were evaluated for the pattern of pancreatic inflammatory cell infiltration and histological features. Ten organ donors served as controls. Haematoxylin and eosin-stained tissue sections were used for histological evaluation. For immunohistochemical characterization of the inflammatory reaction, four antibodies-CD4, CD8, CD45 and CD68-were used. Quantitative evaluation of the various cell infiltrates was performed with computer-assisted image analysis. The inflammatory cell infiltration pattern was also evaluated.

RESULTS

The degree of endophlebitis and the overall density of plasma cells were greater in tropical than in alcoholic chronic pancreatitis. The grade of intralobular fibrosis was significantly higher in tropical chronic pancreatitis compared with the idiopathic form. No significant quantitative differences in the specific cellular infiltrates (CD4, CD8, CD45, CD68) were observed in the three different groups. However, the perivascular inflammation number score was significantly higher in alcoholic compared with idiopathic pancreatitis (P = 0.037), and the perivascular inflammation area score was significantly lower in idiopathic than in alcoholic (P = 0.024) or tropical (P = 0.020) pancreatitis.

CONCLUSION

Different aetiological forms of chronic pancreatitis result in similar histological features and a comparable inflammatory cell reaction, indicating that the disease, independent of the underlying aetiology, reaches a common immunological stage beyond which it appears to progress as a single distinctive entity.

Liver, pancreas and biliary tract enhanced lipoperoxidation products in pure pancreatic juice: evidence for organ-specific oxidative stress in chronic pancreatitis

BACKGROUND

Oxygen-free radicalscan play a role in the development of chronic pancreatitis, altering the redox state with damage of cell constituents and decrease in antioxidant defences.

AIMS

To measure levels of lipoperoxidation products, conjugated dienes and lipid hydroperoxides, in pure pancreatic juice and serum of chronic pancreatitis patients and compare them to that in controls. To investigate a possible correlation with serum indexes of pancreatic inflammation (amylase and lipase).

PATIENTS

Pancreatic juice was collected during ERCP, after secretin stimulation, in 20 patients with chronic pancreatitis and 11 controls with biliary diseases.

METHODS

Lipid hydroperoxide levels were determined with FOX2 method and measured as absorbance at 560 nm. Conjugated diene levels were measured using second-derivative spectroscopy.

RESULTS

No substantial difference was present in serum levels of lipid hydroperoxides, conjugated dienes (in both isomeric forms) and isomer-ratio values between those of patients with chronic pancreatitis and controls. In pancreatic juice, there was a significant increase in lipid hydroperoxides and conjugated dienes levels (especially trans-trans isomers) in chronic pancreatitis patients compared with controls, with a decrease in cis-trans isomers and a significant difference in isomer-ratio values.

CONCLUSIONS

Increased levels of lipid hydroperoxides and conjugated dienes in the pancreatic juice of chronic pancreatitis patients is indicative of an enhanced lipoperoxidation and antioxidants consumption in pancreatic tissue, confirmed by the decreased isomer-ratio values as an indirect index of decreased antioxidant capacity. The lack of significant difference in conjugated diene and lipid hydroperoxide levels in the serum of chronic pancreatitis patients versus that of controls suggests an oxidative stress limited to pancreatic tissue and indicative of an organ-specific pathology, confirmed by the parallel behaviour of oxidative parameters (lipid hydroperoxides and conjugated dienes) and indexes of pancreatic inflammation (amylase and lipase).

Detection of oncogenes in chronic pancreatitis

BACKGROUND

The pathogenesis of chronic pancreatitis (CP) remains poorly understood. Recently, molecular biology has identified the genetic background for many patients with hereditary CP. In addition, a number of studies have focused on the detection of proto-oncogenes and tumour suppressor gene mutations in the pathogenesis of CP. So far, the use of these mutations (with the exception of mutations causing hereditary CP), as diagnostic and prognostic markers is still controversial.

DISCUSSION

It is well known that the risk of pancreatic cancer in patients with CP, especially the hereditary form, is high. At present, there is insufficient evidence to show a clear relationship between the development of pancreatic cancer and certain mutations. New biotechnological methods, such as DNA array expression analysis, expand our knowledge of the molecular pathogenesis of this disease and may help to develop specific diagnostic, prognostic and therapeutic tools. However, until long-term studies examine the safety and efficacy of certain genetic markers, long-term follow-up of patients with CP who harbour mutations is needed.

Growth factors in pancreatic health and disease

In this article the role of different growth factors and their receptors in the pathogenesis of chronic pancreatitis and pancreatic cancer is discussed. The expression of members of the epidermal growth factor family, the fibroblast growth factor family, the transforming growth factor-beta family, the platelet-derived growth factor family, the nerve growth factor family, the insulin-like growth factor family and their signaling receptors is presented, and a correlation of the molecular data with clinical and pathological changes is performed. A number of these growth factors and their receptors are markedly overexpressed in chronic pancreatitis and pancreatic cancer. In chronic pancreatitis, overexpression of growth factors and their receptors contributes to tissue remodeling and fibrogenesis. In contrast to chronic pancreatitis, pancreatic cancer is associated with a variety of genetic alterations, including mutations in tumor suppressor genes and cell cycle regulators. In the presence of these genetic disturbances, enhanced expression of growth factors and their receptors contributes to cell proliferation and enhances the aggressiveness of pancreatic cancer cells. In summary, growth factors and their receptors are often altered in chronic pancreatitis and pancreatic cancer and contribute to various pathogenetic aspects in these disorders.

Identification of disease-specific genes in chronic pancreatitis using DNA array technology

OBJECTIVE

To use DNA arrays to analyze the differential gene expression patterns in the normal pancreas and in pancreatic diseases.

SUMMARY BACKGROUND DATA

Genome-wide gene expression analysis will provide new insights into gene function and cause of disease.

METHODS

RNA was extracted from eight normal pancreatic specimens, eight specimens with chronic pancreatitis (CP), and eight pancreatic cancer (PCa) tissues. Poly A(+) RNA was purified, reverse-transcribed, and converted into cRNA using biotinylated nucleotides. The HuGeneFL DNA array containing 5,600 full-length human genes was used for analysis.

RESULTS

First, normal pancreatic tissues were analyzed in comparison with a panel of other normal tissues (colon, liver, prostate, lung, lymph node). This analysis revealed 11 signature genes that were selectively expressed in the pancreas (e.g., pancreatic elastase-IIA). Comparison of the expression of 5,600 genes between the normal pancreas, CP, and PCa specimens showed that the expression of 34 genes was decreased in CP tissues compared with normal pancreatic tissues, and that the expression of all of these genes was simultaneously decreased in PCa. In addition, the expression of 157 genes was increased in CP tissues compared with the normal pancreas. Of those, 152 genes were simultaneously increased in PCa. Thus, only 5 of 5,600 genes were significantly overexpressed in CP compared with both normal pancreas and PCa.

CONCLUSIONS

The majority of alterations observed in CP are present in PCa, and the number of genes whose expression is selectively deregulated in CP is surprisingly small. These results may provide new insight into the pathobiology of CP and help identify certain molecular alterations that might serve as targets for new diagnostic tools and disease-specific therapy.

Mast cell distribution and activation in chronic pancreatitis

Chronic pancreatitis (CP) is characterized by mononuclear inflammatory cell infiltration and replacement of the destroyed parenchyma by fibrous tissue. Recently, mast cells have been implicated in chronic inflammatory processes with fibrous tissue deposition. Therefore, the number and distribution of mast cells and their state of activation were evaluated in 12 normal specimens and in 46 specimens of CP with different causes (alcoholic, tropical, and idiopathic). Furthermore, the presence of stem cell factor (SCF), the main mast cell growth factor, and of its receptor, c-kit, was also assessed. In CP tissues, mast cells were localized both in the fibrotic areas and in the residual acinar parenchyma. The total number of mast cells was significantly higher in CP than in the normal pancreas (P < .0001) and correlated positively with the extent of fibrosis and the intensity of inflammation. Immunoglobulin E (IgE)-dependent mast cell activation was higher in CP than in the normal pancreas. No differences in mast cell number or IgE positivity were found among the 3 causes of CP. SCF-and c-kit immunoreactive mast cells were mostly localized in fibrous tissue and around regenerating ducts, which were also positive for c-kit but were negative for SCF. These results suggest that mast cells, activated by an IgE-dependent mechanism and/or by an SCF-c-kit autocrine loop, are a relevant component of the inflammatory infiltrate in CP, independent of the underlying cause. Their localization near degenerating acini and regenerating ducts might indicate that they play a crucial role in tissue destruction and remodeling in CP.

Phospholipase A2 isoforms in acute pancreatitis

OBJECTIVE

To assess phospholipase A2 isoforms during human and experimental acute necrotizing pancreatitis. Phospholipase A2 isoforms (group I, II, and IV) were examined in acute pancreatitis tissues in humans and rats to determine whether the exocrine pancreas itself is a source of these mediators.

SUMMARY BACKGROUND DATA

Phospholipase A2 has important regulatory functions, especially in inflammation.

METHODS

Using Northern blot analysis and immunohistochemistry, the expression and localization of phospholipase A2 isoforms were analyzed in pancreatic tissue obtained from 21 patients with acute necrotizing pancreatitis and in pancreatic tissues of rats with acute edematous and necrotizing pancreatitis. Rat samples were examined daily for 1 week.

RESULTS

In human acute pancreatitis, phospholipase A2-I mRNA expression was 8.9-fold decreased. By contrast, phospholipase A2-II (7.8-fold) and phospholipase A2-IV (8.1-fold) mRNA levels were increased. By in situ hybridization, phospholipase A2-IV was found to be expressed in remaining acinar and ductal cells adjacent to the necrotic areas. Immunostaining revealed moderate to intense phospholipase A2-II immunoreactivity in remaining acinar and ductal cells next to the necrosis. In rat pancreatitis, phospholipase A2-II mRNA levels in the pancreas were unchanged in the early phase (8 hours) but markedly increased after 24 hours, with a fluctuating pattern until day 7.

CONCLUSIONS

Enhanced expression of phospholipase A2-II and A2-IV isoenzymes in human and experimental acute pancreatitis suggests that these enzymes play a role in modulating the inflammatory reaction in the pancreas. Because phospholipase A2-II and A2-IV mRNA was strongly present in remaining viable pancreatic acinar and ductal cells, the pancreas itself seems to be at least partly a source and a regulator of phospholipase A2-II- and A2-IV-dependent inflammatory reactions in acute pancreatitis.

Macrophages infiltrating the tissue in chronic pancreatitis express the chemokine receptor CCR5

BACKGROUND

The immunologic mechanisms involved in the development of chronic pancreatitis (CP) are poorly understood. Chronically inflamed tissues contain increased numbers of mononuclear cells expressing the CC chemokine receptor 5 (CCR5), which is also a coreceptor for HIV entry of macrophagetropic strains. However, whether this receptor is involved in the inflammatory process in CP is not known. In the current study, we analyzed the expression of CCR5 in CP. The detection of chemokine receptors on inflammatory cells would strongly suggest their involvement in the pathogenesis of CP (i.e., attraction and activation of these cells). To further evaluate this, we consecutively analyzed the expression of 2 ligands of CCR5: RANTES and MIP-alpha.

METHODS

Pancreatic tissue samples of 22 patients with CP and of 7 healthy pancreas were evaluated. CCR5, RANTES, and MIP-1alpha were analyzed by Northern blot analysis. Consecutive tissue sections were stained for CCR5, CD3, and CD68 to define the leukocyte subtype expressing CCR5 in CP.

RESULTS

By Northern blot analysis, CCR5, RANTES, and MIP-1alpha messenger RNA (mRNA) levels were 12.9-fold, 13.3-fold and 9.2-fold higher in CP specimens compared with healthy controls, respectively (P<.01). Immunostaining for CCR5 revealed a 30-fold increase of CCR5-positive cells in CP tissue compared with the healthy pancreas. Staining of consecutive tissue sections revealed that the majority of CCR5-positive cells were also CD68-positive (macrophages).

CONCLUSIONS

Our data indicate that a remarkable portion of CCR5-positive cells in CP are macrophages. CCR5 is most likely involved in the attraction and activation of these macrophages, since the CCR5 ligands RANTES and MIP-1alpha are concomitantly upregulated.

Changes in pancreatic resection for chronic pancreatitis over 28 years in a single institution

BACKGROUND

Because of advances in knowledge over recent years there is reason to believe that surgical attitudes towards patients with chronic pancreatitis may have changed.

METHODS

Some 547 patients were treated surgically for chronic pancreatitis from 1971 to June 1998. Anastomoses were performed in 80 per cent (438 patients) and resections in 20 per cent (109 patients). Indications and type of operation were analysed, as were mortality and morbidity rates and long-term follow-up results, in patients undergoing resection both over the period as a whole and after dividing the series into two subperiods of 14 years.

RESULTS

In the second 14-year period, there was a significant reduction in the percentage of resections compared with anastomoses (28 per cent (69 of 244 patients) versus 13 per cent (40 of 303); P < 0.0001), and a significant change in the type of resection with a substantial increase in resections of the head compared with those of the body and tail. Statistically significant reductions occurred in operating times, number of units of blood transfused (mean(s.d.) 4.7(3.6) versus 1.2(1.6) units; P = 0.0001) and mean hospital stay (18 versus 14 days for pylorus-preserving and 12 versus 8 days for left pancreatectomy with splenectomy; P < 0. 01); mortality and morbidity rates also tended to decrease, but not significantly.

CONCLUSION

A different pattern has emerged over the years as regards both the type and number of resections performed.

Autoimmune-related pancreatitis is associated with autoantibodies and a Th1/Th2-type cellular immune response

BACKGROUND & AIMS

Although autoimmunity may be involved in some cases of pancreatitis, the mechanism is still unknown. To clarify this, we studied serum autoantibodies, subsets of lymphocytes, and the Th1/Th2 balance of cellular immune responses in patients with autoimmune-related pancreatitis (AIP).

METHODS

Seventeen patients with AIP (8 men and 9 women; age, 53.2 +/- 13.0 years) were studied. Autoantibodies including antilactoferrin (ALF) or carbonic anhydrase II antibody (ACA-II) were examined using the enzyme-linked immunosorbent assay (ELISA) or the indirect fluorescein antibody method. Intracellular cytokines (interferon gamma and interleukin 4) and subtypes of peripheral blood lymphocytes were examined by flow cytometry and ELISA.

RESULTS

More than one autoantibody was observed in all 17 patients. Serum antinuclear antibody was detected in 13 of 17 patients, ALF antibody in 13, ACA-II antibody in 10, rheumatoid factor in 5, and anti-smooth muscle antibody in 3, but antimitochondrial antibody in none. The serum levels of ACA-II and LF antibody were not correlated. HLA-DR(+)CD8(+) and HLA-DR(+)CD4(+) cells were significantly increased in peripheral blood (P < 0.05). CD4(+) cells producing interferon gamma and the secreted levels were significantly increased compared with those in controls (P < 0.05), but interleukin 4 was not increased.

CONCLUSIONS

An autoimmune mechanism against CA-II or LF, and Th1-type immune response, may be involved in AIP.

Nerve growth factor and its high-affinity receptor in chronic pancreatitis

OBJECTIVE

To study the mechanisms that are involved in nerve growth and contribute to pain generation in chronic pancreatitis (CP).

SUMMARY BACKGROUND DATA

Chronic pancreatitis is a painful disease associated with characteristic nerve changes, including an increase in nerve number and diameter. The mechanisms that influence nerve growth are not known. Nerve growth factor (NGF) and its high-affinity tyrosine kinase receptor A (TrkA) are involved in neural development and survival and growth of central and peripheral nerves.

METHODS

Nerve growth factor and TrkA were investigated by Northern blot analysis, in situ hybridization, and immunohistochemical staining in the pancreases of 24 patients with CP, and the findings were correlated with clinical parameters.

RESULTS

By Northern blot analysis, NGF and TrkA mRNA expression were increased in 42% (13.1-fold) and 54% (5.5-fold) of the CP samples (p < 0.01), respectively. In situ hybridization revealed that in CP, enhanced NGF mRNA expression was present in metaplastic ductal cells, in degenerating acinar cells, and in acinar cells dedifferentiating into tubular structures. TrkA mRNA was intensely present in the perineurium. Further, enhanced NGF and TrkA mRNA signals were also present in intrapancreatic ganglia cells in CP samples. Immunohistochemistry confirmed the in situ hybridization findings. Analysis of the molecular findings with clinical parameters revealed a significant relation (p < 0.05) between NGF mRNA levels and pancreatic fibrosis (r = 0.64) and acinar cell damage (r = 0.74) and between TrkA mRNA and pain intensity (r = 0.84).

CONCLUSION

Activation of the NGF/TrkA pathway occurs in CP. It might influence neural morphologic changes and the pain syndrome in this disorder.

Phospholipase A2 isoforms are altered in chronic pancreatitis

OBJECTIVE

To determine if phospholipase A2 (PLA2) type II and type IV mRNA expression and protein are altered in chronic pancreatitis.

SUMMARY BACKGROUND DATA

PLA2s have an important regulatory function in several signaling pathways, especially in inflammation. In this study, we examined the expression of three PLA2 isoforms (type I, type II, and type IV) in chronic pancreatitis.

METHODS

The distribution of PLA2 was studied in 15 pancreas samples obtained from patients with chronic pancreatitis using immunohistochemical, Northern blot, and in situ hybridization techniques. Normal pancreas obtained from healthy organ donors served as control.

RESULTS

Northern blot analysis revealed enhanced mRNA levels of PLA2 type II (5.7-fold) and type IV (5.1-fold) in chronic pancreatitis (p < 0.01) versus normal pancreas. In normal pancreas, intense PLA2 type I immunostaining was present in acinar cells, whereas PLA2 type II immunostaining was visible only in some acinar cells. In chronic pancreatitis, PLA2 type II immunostaining was present more frequently and with higher intensity in acinar cells. Furthermore, PLA2 type II immunoreactivity was more abundant in metaplastic ductal cells in the chronic pancreatitis samples. By in situ hybridization, areas with ductal metaplasia in chronic pancreatitis exhibited intense PLA2 type IV mRNA signals. All chronic pancreatitis tissues with concomitantly increased mRNA expression for PLA2 type II and type IV exhibited a higher degree of degeneration, ductal metaplasia, and fibrosis.

CONCLUSIONS

Upregulation of PLA2 types II and IV in areas with more histologic damage suggests that these PLA2 isoforms might contribute to the morphologic changes that occur in chronic pancreatitis.

A subgroup of patients with chronic pancreatitis overexpress the c-erb B-2 protooncogene

OBJECTIVE

Chronic pancreatitis (CP) is a chronic condition associated with pancreatic fibrosis. A small subgroup of patients with CP develop enlargement of the head of the pancreas (EHP). This study examined some of the mechanisms that may lead to the development of EHP.

SUMMARY BACKGROUND

The c-erb B-2 protooncogene encodes a 185-kDa transmembrane growth factor receptor (p185) that regulates cell growth and differentiation.

METHODS

The authors analyzed c-erb B-2 expression in samples obtained from the head of the pancreas from 26 patients with CP (5 women, 21 men) using immunohistochemical and molecular technique. A diagnosis of CP with EHP was made when the vertical pancreatic head diameter was greater than 4 cm (14 patients), as determined by contrast-enhanced computed axial tomography scan. Pancreatic tissues from 15 healthy organ donors served as control subjects.

RESULTS

In all patients without EHP and in the healthy control subjects, p185 immunoreactivity was present at low levels. In contrast, strong p185 immunoreactivity was observed in acinar and ductal cells in all patients with EHP. By in situ hybridization, c-erb B-2 messenger ribonucleic acid (mRNA) grains were expressed at high levels in patients with CP with EHP in both ductal and acinar cells. Northern blot analysis demonstrated a 4.5-fold increase (p < 0.001) in c-erb B-2 mRNA levels in patients with EHP compared with patients without EHP and healthy control subjects. Southern blot analysis did not reveal c-erb B-2 gene amplification or rearrangement.

CONCLUSIONS

These findings indicate the c-erb B-2 is not overexpressed in most patients with CP. However, its overexpression in patients with CP with EHP suggest that c-erb B-2 may contribute to the pathophysiologic processes that lead to pancreatic head enlargement.