The role of inflammatory and parenchymal cells in acute pancreatitis

Serum Gc-globulin levels are reduced in patients with severe acute pancreatitis

BACKGROUND AND AIM

To investigate the role of group-specific component globulin (Gc-globulin) in the early process of severe acute pancreatitis (SAP).

PATIENTS AND METHODS

A total of 37 patients with SAP and 31 patients with mild acute pancreatitis (MAP) were enrolled in the study. Twenty healthy individuals served as controls. Blood samples were taken from SAP and MAP patients on the day of admission (day 1), day 7, and day 14. Serum total Gc-globulin levels were measured using an enzyme-linked immunosorbent assay.

RESULTS

On admission, the total Gc-globulin levels of patients in the SAP group were 368 (270-455) mg/l (expressed as medians with interquartile range), which were significantly lower (P=0.007) compared with the control group [420 (299-585) mg/l]. In the SAP group, a significant decrease in serum total Gc-globulin was observed in patients who developed organ dysfunction [267 (242-306) mg/l] compared with patients who did not [414 (329-513) mg/l, P<0.001]. Patients with lower Gc-globulin levels were at a higher risk of developing organ dysfunction (P=0.005). Furthermore, serial measurements displayed increasing total Gc-globulin levels in survivors.

CONCLUSION

Decreased total Gc-globulin was linked to poor outcomes of SAP. These data support our hypothesis that Gc-globulin may play an important role in the early process of acute pancreatitis. Gc-globulin might be a novel target for prognosis and therapy of SAP.

Cytosolic double-stranded DNA as a damage-associated molecular pattern induces the inflammatory response in rat pancreatic stellate cells: a plausible mechanism for tissue injury-associated pancreatitis

Pancreatitis is an inflammatory disease of unknown causes. There are many triggers causing pancreatitis, such as alcohol, common bile duct stone, virus and congenital or acquired stenosis of main pancreatic duct, which often involve tissue injuries. Pancreatitis often occurs in sterile condition, where the dead/dying pancreatic parenchymal cells and the necrotic tissues derived from self-digested-pancreas were observed. However, the causal relationship between tissue injury and pancreatitis and how tissue injury could induce the inflammation of the pancreas were not elucidated fully until now. This study demonstrates that cytosolic double-stranded DNA increases the expression of several inflammatory genes (cytokines, chemokines, type I interferon, and major histocompatibility complex) in rat pancreatic stellate cells. Furthermore, these increase accompanied the multiple signal molecules genes, such as interferon regulatory factors, nuclear factor-kappa B, low-molecular-weight protein 2, and transporter associated with antigen processing 1. We suggest that this phenomenon is a plausible mechanism that might explain how cell damage of the pancreas or tissue injury triggers acute, chronic, and autoimmune pancreatitis; it is potentially relevant to host immune responses induced during alcohol consumption or other causes.

Shock - A reappraisal: The holistic approach

Shock as reaction to life-threatening condition needs to be reclassified in a timely and more scientific synopsis. It is not possible or beneficial any longer to avoid a holistic approach in critical illness. Semantics of critical illness has often been unfriendly in the literature and a simplification with the elimination of conceptual pleonasms and misnomers under the exclusive light of physiology and physiopathology would be advantageous. Speaking one language to describe the same phenomenon worldwide is essential for understanding; moreover, it increases focus on characterization and significance of the phenomena.

miR-15b and miR-16 induce the apoptosis of rat activated pancreatic stellate cells by targeting Bcl-2 in vitro

OBJECTIVES

Activated pancreatic stellate cells (PSCs) play a pivotal role in the development of pancreatic diseases, especially chronic pancreatitis and pancreatic cancer. MicroRNAs have become a focal point of interest as post-transcriptional regulators of gene expression via their interaction with the 3' untranslated region of target mRNAs, which results in gene silencing. We examined the relative expression of microRNAs (miR-15b and miR-16) and their target gene, Bcl-2, during activation of rat PSCs, and determined their effects on apoptosis of rat PSCs in vitro.

METHODS

miR-15b and miR-16 expression levels were analyzed in quiescent and activated PSCs by stem-loop RT-PCR. In addition, the effects of miR-15b and miR-16 on apoptosis of activated PSCs were investigated by immunofluorescence microscopy with Hoechst 33342 staining, and flow cytometry with annexin-V/propidium (PI) co-labeling. Bcl-2 and Bcl-xl were also analyzed by real-time RT-PCR and Western blotting.

RESULTS

During activation of PSCs, from the quiescent stage to activated stage, miR-15b and miR_16 were downregulated, while Bcl-2 expression was upregulated. Restoring intracellular miRNA levels by miR-15b and miR-16 administration greatly reduced Bcl-2 protein levels, and significantly induced apoptosis in activated PSCs.

CONCLUSIONS

miR-15b and miR-16 could induce apoptosis of rat PSCs by targeting Bcl-2.

The fibrosis of chronic pancreatitis: new insights into the role of pancreatic stellate cells

SIGNIFICANCE

Prominent fibrosis is a major histological feature of chronic pancreatitis, a progressive necroinflammatory condition of the pancreas, most commonly associated with alcohol abuse. Patients with this disease often develop exocrine and endocrine insufficiency characterized by maldigestion and diabetes. Up until just over a decade ago, there was little understanding of the pathogenesis of pancreatic fibrosis in chronic pancreatitis.

RECENT ADVANCES

In recent times, significant progress has been made in this area, mostly due to the identification, isolation, and characterization of the cells, namely pancreatic stellate cells (PSCs) that are now established as key players in pancreatic fibrogenesis. In health, PSCs maintain normal tissue architecture via regulation of the synthesis and degradation of extracellular matrix (ECM) proteins. During pancreatic injury, PSCs transform into an activated phenotype that secretes excessive amounts of the ECM proteins that comprise fibrous tissue.

CRITICAL ISSUES

This Review summarizes current knowledge and critical aspects of PSC biology which have been increasingly well characterized over the past few years, particularly with respect to the response of PSCs to factors that stimulate or inhibit their activation and the intracellular signaling pathways governing these processes. Based on this knowledge, several therapeutic strategies have been examined in experimental models of pancreatic fibrosis, demonstrating that pancreatic fibrosis is a potentially reversible condition, at least in early stages.

FUTURE DIRECTIONS

These will involve translation of the laboratory findings into effective clinical approaches to prevent/inhibit PSC activation so as to prevent, retard, or reverse the fibrotic process in pancreatitis.

Sesamol attenuates oxidative stress–mediated experimental acute pancreatitis in rats

Acute pancreatitis is a potentially fatal disease with no known cure. The initial events in acute pancreatitis may occur within the acinar cells. We examined the effect of sesamol on (i) a cerulein-induced pancreatic acinar cancer cell line, AR42J, and (ii) cerulein-induced experimental acute pancreatitis in rats. Sesamol inhibited amylase activity and increased cell survival. It also inhibited medium lipid peroxidation and 8-hydroxydeoxyguanosine in AR42J cells compared with the cerulein-alone groups. In addition, in cerulein-treated rats, sesamol inhibited serum amylase and lipase levels, pancreatic edema, and lipid peroxidation, but it increased pancreatic glutathione and nitric oxide levels. Thus, we hypothesize that sesamol attenuates cerulein-induced experimental acute pancreatitis by inhibiting the pancreatic acinar cell death associated with oxidative stress in rats.

Proteomic analysis of a rat pancreatic stellate cell line using liquid chromatography tandem mass spectrometry (LC-MS/MS)

Pancreatic stellate cells (PaSC) are emerging as key mediators in chronic pancreatitis and pancreatic cancer pathogenesis. Proteins regulating the biomolecular pathways involved in the conversion of quiescent to activated PaSC may have a significant influence on the development of chronic pancreatitis. We aim to compare differentially expressed proteins in activated and serum-starved non-proliferating PaSC using a mass spectrometry-based proteomics strategy. We cultured an immortalized rat PaSC cell line in media supplemented with 10% fetal bovine serum and in serum-free media. Using gel-based mass spectrometry (GeLC-MS/MS), we identified nearly 1500 proteins. Qualitative and quantitative proteomic analysis revealed several hundred proteins as differentially abundant between the two cell states. Proteins of greater abundance in activated PaSC included isoforms of actin (e.g., smooth muscle actin) and ribosomal proteins. Conversely, proteins more abundant in non-proliferating PaSC than in activated PaSC included signaling proteins MAP kinase 3 and Ras-related proteins. In addition, we have determined the molecular functions and biological pathways for these proteins. We are confident that the application of mass spectrometry-based strategies, such as that described herein, to investigate specific proteins in PaSC may lead to a better understanding of the molecular mechanisms involved in pancreatic diseases, such as chronic pancreatitis.

Admission levels of soluble CD137 are increased in patients with acute pancreatitis and are associated with subsequent complications

The progression of acute pancreatitis to necrotizing pancreatitis which often results in high morbidity and mortality is difficult to predict. Here we report that serum concentrations of sCD137 are increased in patients with acute pancreatitis. Admission levels and 10-day median sCD137 levels positively correlate with markers of biliary pancreatitis and the 10-day sCD137 median is significantly higher in metabolic than in alcoholic pancreatitis. Serum concentrations of sCD137 at time of admission and the 10-day median of sCD137 correlate with the Ranson and APACHE II disease scores but not with the radiological Balthazar and Schroeder scores that reflect pancreatic and peripancreatic necrosis. Further, sCD137 levels correlate with the probability of complications and lethality. The association of sCD137, a product of activated T cells, with the severity of acute pancreatitis suggests that T cells contribute to the pathogenesis of acute pancreatitis.

Proteomic analysis of an immortalized mouse pancreatic stellate cell line identifies differentially-expressed proteins in activated vs nonproliferating cell states

Pancreatic stellate cells (PaSC) are mediators in chronic pancreatitis and pancreatic cancer pathogenesis. Proteins regulating the biomolecular pathways involved in the conversion of activated to quiescent PaSC may have a significant influence in the development of chronic pancreatitis. We aim to compare differentially expressed proteins from an immortalized cell line of mouse PaSC in the activated and serum-starved cell states using mass spectrometry-based proteomics. PaSC cultured in media supplemented with fetal bovine serum (FBS) proliferate in the activated state, while serum starvation promotes the cellular transition to a "pseudo-quiescent" state. Using these two cell states, we performed a comparative mass spectrometry (GeLC-MS/MS) proteomic analysis. We identified over 2000 nonredundant proteins in PaSC. Qualitative and label-free quantitative analysis revealed several hundred proteins that were differentially abundant between the cell states. Proteins that were more abundant in activated PaSC included cytoskeletal proteins and ribosomal proteins, while those more abundant in pseudoquiescent PaSC included proteins involved in protein degradation-related pathways (lysosome, ubiquitin-mediated proteolysis, and the proteasome). Investigation of the role of PaSC in the pathogenesis of chronic pancreatitis using the mass spectrometry-based proteomics strategy described herein will lead to further insights into the molecular mechanisms associated with the disease.

Cytokine profiling of pancreatic fluid using the ePFT collection method in tandem with a multiplexed microarray assay

Cytokines are secreted immunomodulating proteins involved in pancreatic stellate cell activation and propagation of fibrosis in chronic pancreatitis. We aim to show that cytokines can be identified from pancreatic fluid by (1) collecting pancreatic fluid with the ePFT method, (2) processing the fluid for cytokine-targeted microarray analysis, and (3) comparing cytokine profiles in pancreatic fluid of chronic pancreatitis (CP) patients and of chronic abdominal pain (CAP) controls. We endoscopically collected pancreatic fluid from patients with CP and those with CAP using the ePFT method. This fluid was subjected directly to a multiplexed cytokine protein microarray assay. Six patients (3 CP, 3 CAP) underwent a secretin-stimulated ePFT. The mean peak bicarbonate concentrations [meq/L] of the CP and CAP patients were 43 and 97, respectively. Statistically significant decreases in the cytokine concentrations of EGF, IP-10, eotaxin, IL-3, MIP-1a, IL-15, PDGF-AB/BB, and IL-1a were observed in the CP specimens (p<0.05). We have successfully identified differences in the abundance of cytokines in ePFT-collected pancreatic fluid with a multiplexed microarray assay comparing CP and CAP controls. Further targeted investigation of cytokines in ePFT-collected fluid will broaden our knowledge of pancreatic immune response and pathogenesis in chronic pancreatitis.

Prophylactic glycine administration attenuates pancreatic damage and inflammation in experimental acute pancreatitis

BACKGROUND/AIMS

Acute pancreatitis (AP) is characterized by premature zymogen activation, systemic inflammatory response resulting in inflammatory infiltrates, sustained intracellular calcium, neurogenic inflammation and pain. The inhibitory neurotransmitter and cytoprotective amino acid glycine exerts a direct inhibitory effect on inflammatory cells, inhibits calcium influx and neuronal activation and therefore represents a putative therapeutic agent in AP.

METHODS

To explore the impact of glycine, mild AP was induced in rats by supramaximal cerulein stimulation (10 μg/kg BW/h) and severe AP by retrograde injection of sodium taurocholate solution (3%) into the common biliopancreatic duct. 100/300 mmol glycine was administered intravenously before induction of AP. To elucidate the effect of glycine on AP, we determined pathomorphology, pancreatic cytokines as well as proteases, serum lipase and amylase, pancreatic and lung MPO activity and pain sensation.

RESULTS

Glycine administration resulted in a noticeable improvement of pathomorphological alterations in AP, such as a reduction of necrosis, inflammatory infiltrates and cytoplasmic vacuoles in cerulein pancreatitis. In taurocholate pancreatitis, glycine additionally diminished pancreatic cytokines and MPO activity, as well as serum lipase and amylase levels.

CONCLUSIONS

Glycine reduced the severity of mild and much more of severe AP by attenuating the intrapancreatic and systemic inflammatory response. Therefore, glycine seems to be a promising tool for prophylactic treatment of AP. and IAP.

Cannabinoid agonist WIN55,212 in vitro inhibits interleukin-6 (IL-6) and monocyte chemo-attractant protein-1 (MCP-1) release by rat pancreatic acini and in vivo induces dual effects on the course of acute pancreatitis

BACKGROUND

Cannabinoids (CBs) evoke their effects by activating the cannabinoid receptor subtypes CB1-r and CB2-r and exert anti-inflammatory effects altering chemokine and cytokine expression. Various cytokines and chemokines are produced and released by rodent pancreatic acini in acute pancreatitis. Although CB1-r and CB2-r expressed in rat exocrine pancreatic acinar cells do not modulate digestive enzyme release, whether they modulate inflammatory mediators remains unclear. We investigated the CB-r system role on exocrine pancreas in unstimulated conditions and during acute pancreatitis.

METHODS

We evaluated in vitro and in vivo changes induced by WIN55,212 on the inflammatory variables amylasemia, pancreatic edema and morphology, and on acinar release and content of the cytokine interleukin-6 (IL-6) and chemokine monocyte chemo-attractant protein-1 (MCP-1) in untreated rats and rats with caerulein (CK)-induced pancreatitis.

KEY RESULTS

In the in vitro experiments, WIN55,212 (10(-6) mol L(-1)) inhibited IL-6 and MCP-1 release from acinar cells of unstimulated rats and after CK-induced pancreatitis. In vivo, when rats were pretreated with WIN55,212 (2 mg kg(-1), intraperitoneally) before experimentally-induced pancreatitis, serum amylase, pancreatic edema and IL-6 and MCP-1 acinar content diminished and pancreatic morphology improved. Conversely, when rats with experimentally-induced pancreatitis were post-treated with WIN55,212, pancreatitis worsened.

CONCLUSIONS & INFERENCES

These findings provide new evidence showing that the pancreatic CB1-r/CB2-r system modulates pro-inflammatory factor levels in rat exocrine pancreatic acinar cells. The dual, time-dependent WIN55,212-induced changes in the development and course of acute pancreatitis support the idea that the role of the endogenous CB receptor system differs according to the local inflammatory status.

Acute pancreatitis

Acute pancreatitis (AP) is an important cause of morbidity and mortality worldwide and the annual incidence appears to be increasing. It presents as a mild self-limiting illness in 80% of patients. However, one-fifth of these develop a severe complicated life-threatening disease requiring intensive and prolonged therapeutic intervention. Alcohol and gallstone disease remain the commonest causes of AP but metabolic abnormalities, obesity and genetic susceptibility are thought be increasingly important aetiological factors. The prompt diagnosis of AP and stratification of disease severity is essential in directing rapid delivery of appropriate therapeutic measures. In this review, the range of diagnostic and prognostic assays, severity scoring systems and radiological investigations used in current clinical practice are described, highlighting their strengths and weaknesses. Increased understanding of the complex pathophysiology of AP has generated an array of new potential diagnostic assays and these are discussed. The multidisciplinary approach to management of severe pancreatitis is outlined, including areas of controversy and novel treatments.

Transcriptional regulation of CXC-ELR chemokines KC and MIP-2 in mouse pancreatic acini

Neutrophils and their chemoattractants, the CXC-ELR chemokines keratinocyte cytokine (KC) and macrophage inflammatory protein-2 (MIP-2), play a critical role in pancreatitis. While acute pancreatitis is initiated in acinar cells, it is unclear if these are a source of CXC-ELR chemokines. KC and MIP-2 have NF-κB, activator protein-1 (AP-1) sites in their promoter regions. However, previous studies have shown increased basal and reduced caerulein-induced AP-1 activation in harvested pancreatic tissue in vitro, which limits interpreting the caerulein-induced response. Moreover, recent studies suggest that NF-κB silencing in acinar cells alone may not be sufficient to reduce inflammation in acute pancreatitis. Thus the aim of this study was to determine whether acinar cells are a source of KC and MIP-2 and to understand their transcriptional regulation. Primary overnight-cultured murine pancreatic acini were used after confirming their ability to replicate physiological and pathological acinar cell responses. Upstream signaling resulting in KC, MIP-2 upregulation was studied along with activation of the transcription factors NF-κB and AP-1. Cultured acini replicated critical responses to physiological and pathological caerulein concentrations. KC and MIP-2 mRNA levels increased in response to supramaximal but not to physiological caerulein doses. This upregulation was calcium and protein kinase C (PKC), but not cAMP, dependent. NF-κB inhibition completely prevented upregulation of KC but not MIP-2. Complete suppression of MIP-2 upregulation required dual inhibition of NF-κB and AP-1. Acinar cells are a likely source of KC and MIP-2 upregulation during pancreatitis. This upregulation is dependent on calcium and PKC. MIP-2 upregulation requires both NF-κB and AP-1 in these cells. Thus dual inhibition of NF-κB and AP-1 may be a more successful strategy to reduce inflammation in pancreatitis than targeting NF-κB alone.

Different profiles of cytokine expression during mild and severe acute pancreatitis

AIM

To study secretion patterns of pro- and anti-inflammatory cytokines, and activation of various cellular subsets of leukocytes in peripheral blood.

METHODS

We have conducted a prospective observational study. One hundred and eight patients with a diagnosis of acute pancreatitis and onset of the disease within last 72 h were included in this study. The mRNA expression of 25 different types of cytokines in white blood cells was determined by quantitative real time polymerase chain reaction. Levels of 8 different cytokines in blood serum were measured by enzyme linked immunosorbent assay. Clinical data and cytokine expression results were subjected to statistical analysis.

RESULTS

Severe and necrotizing acute pancreatitis (AP) is characterized by the significant depletion of circulating lymphocytes. Severe acute pancreatitis is associated with a typical systemic inflammatory response syndrome and over-expression of pro-inflammatory cytokines [interleukin (IL)-6, IL-8, macrophage migration inhibitory factor (MIF)]. Serum IL-6 and MIF concentrations are the best discriminators of severe and necrotizing AP as well as possible fatal outcome during the early course of the disease.

CONCLUSION

Deregulation of cellular immune system is a key event leading to severe and necrotizing AP. IL-6 and MIF could be used as early predictors of complications.

Connections between genetics and clinical data: Role of MCP-1, CFTR, and SPINK-1 in the setting of acute, acute recurrent, and chronic pancreatitis

OBJECTIVES

Acute, acute recurrent, and chronic pancreatitis are inflammatory diseases with multifactorial pathogenic mechanisms. Genetic mutations and polymorphisms have been correlated with pancreatitis. The aim of this study was to investigate the association of cystic fibrosis transmembrane conductance regulator (CFTR) and serine protease inhibitor Kazal type 1 (SPINK-1) gene mutations and monocyte chemoattractant protein 1 (MCP-1) -2518A/G polymorphism with acute pancreatitis (AP), acute recurrent pancreatitis (ARP), and chronic pancreatitis (CP), and to associate genetic backgrounds with clinical phenotype in these three conditions.

METHODS

One hundred eighteen AP, 64 ARP, 142 CP patients, and 88 normal controls were enrolled consecutively. We analyzed MCP-1 serum levels using enzyme-linked immunosorbent assay. Polymorphism -2518 of MCP-1 and SPINK-1 N34S gene mutations were determined by PCR-restriction-fragment length polymorphism. Sequence analysis was performed when necessary. Thirty-three CFTR mutations were analyzed in CP and ARP patients using multiplex DNA testing.

RESULTS

Serum MCP-1 levels were significantly higher in all patients affected by pancreatic inflammatory diseases. Moreover, we found a significant over-representation of the MCP-1G allele in ARP patients. We found a statistically significant association of CFTR gene mutations with ARP, but not with CP. We did not find a statistically significant association of ARP or CP with the N34S SPINK-1 gene mutation. Interestingly, 39 of 64 ARP patients (61%) carried at least one genetic mutation and/or polymorphism. Five of 64 ARP patients had pancreas divisum and four of these five also carried the G allele.

CONCLUSIONS

Analysis of a comprehensive range of potential susceptibility variants is needed to support modeling of the effects of genes and environment in pancreatitis. As such, beyond gene mutations, the context within which those mutations exist must be considered. In pancreatitis the context includes the inflammatory response, clinical features, and exogenous factors.

Pancreatic stellate/myofibroblast cells express G-protein-coupled melatonin receptor 1

In chronic pancreatitis and pancreatic cancer, progressive fibrosis with the accumulation of extracellular matrix occurs. The main extracellular matrix-producing cell types are retinoid-storing pancreatic stellate cells (PSCs) of mesenchymal origin. Similar to liver stellate cells, quiescent PSCs undergo activation and acquire a myofibroblast-like phenotype in response to pro-fibrogenic mediators (reactive oxygen species, cytokines and toxic metabolites). Activated PSCs differ in their differentiation stage and are characterized by the expression of glial fibrillary-acidic protein, alpha-smooth muscle actin, and nestin. As G-protein-coupled receptors were described to regulate PSC differentiation, we investigated tissue samples from patients with pancreatitis and ductal pancreatic adenocarcinoma for the expression of G-protein-coupled melatonin receptors MT1 and MT2 by double immunofluorescence staining. We show that MT1, but not MT2, is occasionally expressed in PSCs in normal tissue, while in the diseased tissue MT1 is found at high rates in activated PSCs at all stages, and, additionally, in ductal epithelial cells. It is speculated that MT1 activation by its ligand melatonin regulates proliferation and differentiation of PSCs. Prevention of myofibroblast formation by MT1 activation could explain favourable effects of the pineal hormone melatonin on the outcome of pancreatic fibrosis in animal models.

The changing character of acute pancreatitis: epidemiology, etiology, and prognosis

Acute pancreatitis continues to be a diagnostic and therapeutic challenge for physicians and surgeons. It ranks third in the list of hospital discharges for gastro-intestinal diseases. In most patients the cause is either gallstones or alcoholism. The overall mortality is less than 5%, but severe acute pancreatitis leads to prolonged hospitalization and much higher mortality. There are important differences in disease susceptibility and case fatality rates: the incidence is higher in blacks than in whites, and mortality is higher in older patients than in younger patients. Reports from various countries reveal that the frequency of acute pancreatitis is increasing, perhaps in relation to rising obesity rates, which would increase the likelihood of gallstone pancreatitis. Conversely, mortality rates for acute pancreatitis are declining in many, but not all, reports.

Cell-permeable Tat-NBD peptide attenuates rat pancreatitis and acinus cell inflammation response

AIM

To investigate the effects of Tat-NEMO-binding domain (NBD) peptide on taurocholate-induced pancreatitis and lipopolysaccharide (LPS)-stimulated AR42J acinus cells inflammatory response in rats.

METHODS

Sodium taurocholate (5%) was used to induce the pancreatitis model. Forty-eight rats from the taurocholate group received an intravenous bolus of 13 mg/kg Tat-NBD (wild-type, WT) peptide, Tat-NBD (mutant-type, MT) peptide, NBD peptide or Tat peptide. The pancreatic histopathology was analyzed by hematoxylin staining. LPS was added to the culture medium to stimulate the AR42J cells. For pretreatment, cells were incubated with different peptides for 2 h before LPS stimulation. Expression of IL-1beta and TNF-alpha mRNA was analyzed using a semi-quantitative reverse-transcript polymerase chain reaction (RT-PCR) method. IL-1beta and TNF-alpha protein in culture medium were detected by enzyme linked immunosorbent assay (ELISA). NF-kappaB DNA-binding in pancreas was examined by electrophoretic mobility shift assays. P65 expression of AR42J was determined by Strept Actividin-Biotin Complex (SABC) method.

RESULTS

Pretreatment with Tat-NBD (WT) peptide at a concentration of 13 mg/kg body wt showed beneficial effect in pancreaitis model. LPS (10 mg/L) resulted in an increase of IL-1beta mRNA, IL-1beta protein, TNF-alpha mRNA and TNF-alpha protein, whereas significantly inhibitory effects were observed when cells were incubated with Tat-NBD (WT). Consisting with p65 expression decrease analyzed by SABC method, NF-kappaB DNA-binding activity significantly decreased in Tat-NBD (WT) pretreatment group, especially at the largest dose. No significant changes were found in the control peptide group.

CONCLUSION

Our result supports that active NF-kappaB participates in the pathogenesis of STC-induced acute pancreatitis in rats. Tat-NBD (WT) peptide has anti-inflammatory effects in this model and inhibits the inflammation of acinus simulated by LPS.

Rosiglitazone attenuates the severity of sodium taurocholate-induced acute pancreatitis and pancreatitis-associated lung injury

BACKGROUND AND AIMS

In addition to the effect of regulating adipocyte differentiation and insulin sensitivity, peroxisome proliferator activated receptor-gamma (PPAR-gamma) ligands also exhibit anti-inflammatory effect. However, the mechanisms concerning how PPAR-gamma ligands affect acute pancreatitis and pancreatitis-associated lung injury have not been fully elucidated. This study investigated the effect of rosiglitazone, a PPAR-gamma ligand, on acute pancreatitis and pancreatitis-associated lung injury in the rat pancreatitis model induced by sodium taurocholate.

METHODS

Acute pancreatitis was induced by retrograde infusion of 5% sodium taurocholate (1 mL/kg) into the bile-pancreatic duct. Rosiglitazone (6 mg/kg) was administered via the femoral vein 30 min prior to the infusion of sodium taurocholate. The severity of pancreatitis was evaluated by serum amylase level, myeloperoxidase activity, and pathology. Pancreatitis-associated lung injury was evaluated by myeloperoxidase activity, the magnitude of pulmonary edema and pathology. Intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-alpha mRNA expression were studied using reverse transcriptase polymerase chain reaction. ICAM-1 protein expression was studied using Western blot analysis.

RESULTS

Prophylactic administration of rosiglitazone attenuated (1) serum amylase level; (2) myeloperoxidase activity of pancreatic and pulmonary tissue; (3) expression of tumor necrosis factor-alpha and ICAM-1 in pancreas and lung; (4) pancreas and lung pathological damage.

CONCLUSIONS

Our study demonstrated that rosiglitazone exerts a protective effect against sodium taurocholate-induced pancreatic and pulmonary injury.

Reduction of inflammation and chronic tissue damage by omega-3 fatty acids in fat-1 transgenic mice with pancreatitis

Pancreatitis is a severe debilitating disease with high morbidity and mortality. Treatment is mostly supportive, and until now there are no clinically useful strategies for anti-inflammatory therapy. Although omega-3 polyunsaturated fatty acids (n-3 PUFA) are known to have anti-inflammatory effects, the utility of these fatty acids in the alleviation of pancreatitis remained to be investigated. The aim of this study was to examine the effect of n-3 PUFA on both acute and chronic pancreatitis in a well-controlled experimental system. We used the fat-1 transgenic mouse model, characterized by endogenously increased tissue levels of n-3 PUFA, and their wild-type littermates to examine the effect of n-3 PUFA on both acute and chronic cerulein-induced pancreatitis. Disease activity and inflammatory status were assessed by both histology and molecular methods. In acute pancreatitis, fat-1 mice showed a trend towards decreased necrosis and significantly reduced levels of plasma IL-6 levels as well as reduced neutrophil infiltration in the lung. In chronic pancreatitis there was less pancreatic fibrosis and collagen content accompanied by decreased pancreatic stellate cell activation in the fat-1 animals with increased n-3 PUFA tissue levels as compared to wild-type littermates with high levels of omega-6 (n-6) PUFA in their tissues. Our data provide evidence for a reduction of systemic inflammation in acute pancreatitis and of tissue fibrosis in chronic pancreatitis by increasing the tissue content of omega-3 polyunsaturated fatty acids. These results suggest a beneficial potential for n-3 PUFA supplementation in acute and particularly chronic pancreatitis.