Inflammatory mediators in acute pancreatitis

Severe Acute Pancreatitis Prediction: A Model Derived From a Prospective Registry Cohort

Background Severe acute pancreatitis (SAP) has a mortality rate as high as 40%. Early identification of SAP is required to appropriately triage and direct initial therapies. The purpose of this study was to develop a prognostic model that identifies patients at risk for developing SAP of patients managed according to a guideline-based standardized early medical management (EMM) protocol. Methods This single-center study included all patients diagnosed with acute pancreatitis (AP) and managed with the EMM protocol Methodist Acute Pancreatitis Protocol (MAPP) between April 2017 and September 2022. Classification and regression tree (CART®; Professional Extended Edition, version 8.0; Salford Systems, San Diego, CA), univariate, and logistic regression analyses were performed to develop a scoring system for AP severity prediction. The accuracy of the scoring system was measured by the area under the receiver operating characteristic curve. Results A total of 516 patients with mild (n=436) or moderately severe and severe (n=80) AP were analyzed. CART analysis identified the cutoff values: creatinine (CR) (1.15 mg/dL), white blood cells (WBC) (10.5 × 109/L), procalcitonin (PCT) (0.155 ng/mL), and systemic inflammatory response system (SIRS). The prediction model was built with a multivariable logistic regression analysis, which identified CR, WBC, PCT, and SIRS as the main predictors of severity. When CR and only one other predictor value (WBC, PCT, or SIRS) met thresholds, then the probability of predicting SAP was >30%. The probability of predicting SAP was 72% (95%CI: 0.59-0.82) if all four of the main predictors were greater than the cutoff values. Conclusions Baseline laboratory cutoff values were identified and a logistic regression-based prognostic model was developed to identify patients treated with a standardized EMM who were at risk for SAP.

Fibrosis in Liver and Pancreas: a Review on Pathogenic Significance, Diagnostic Options, and Current Management Strategies

Inflammation is one of the most natural ways of the body's biological response against invading foreign pathogens or injured cells which eventually can lead to a chronic or acute productive response. Fibrosis is an end-stage event associated with an inflammatory response addressed with tissue hardening, discoloration, and most importantly overgrowth of associated tissue. Various organs at different diseased conditions are affected by fibrosis including the liver, pancreas, brain, kidney, and lung. Etiological factors including internal like inflammatory cytokines, growth factors, and oxidative stress and external like alcohol and viruses contribute to the development of fibrosis in both the liver and pancreas. More frequently, these organs are associated with pathogenic progression towards fibrosis from acute and chronic conditions and eventually fail in their functions. The pathogenesis of the organ-fibrotic events mainly depends on the activation of residential stellate cells; these cells help to accumulate collagen in respective organs. Various diagnostic options have been developed recently, and various therapeutic options are in trial to tackle fibrosis. In this review, an overview on fibrosis, the pathogenesis of fibrosis in the liver and pancreas, various diagnostic options developed in recent years, and possible present therapeutic measures to overcome options of fibrosis in the liver and pancreas; thus, restoring the functional status of organs is discussed.

Rectal nonsteroidal anti-inflammatory drugs, glyceryl trinitrate, or combinations for prophylaxis of post-endoscopic retrograde cholangiopancreatography pancreatitis: A network meta-analysis

BACKGROUND

Acute pancreatitis is the most common and severe complication of endoscopic retrograde cholangiopancreatography (ERCP). Recent evidence suggests that combinations based on rectal nonsteroidal anti-inflammatory drugs (NSAIDs) are more beneficial in preventing post-ERCP pancreatitis (PEP). Randomized controlled trials (RCTs) have also demonstrated the efficacy of glyceryl trinitrate (GTN). We conducted a network meta-analysis to compare NSAIDs and GTN for prevention of PEP and to determine whether they are better in combination.

AIM

To compare NSAIDs and GTN for prevention of PEP and to determine whether they are better in combination.

METHODS

A systematic search was done for full-text RCTs of PEP in PubMed, Embase, Science Citation Index, and the Cochrane Controlled Trials database. Inclusion and exclusion criteria were used to screen for eligible RCTs. The major data were extracted by two independent reviewers. The frequentist model was used to conduct this network meta-analysis and obtain the pairwise OR and 95%CI. The data were then extracted and assessed on the basis of the Reference Citation Analysis (https://www.referencecitationanalysis.com/).

RESULTS

Twenty-four eligible RCTs were selected, evaluating seven preventive strategies in 9416 patients. Rectal indomethacin 100 mg plus sublingual GTN (OR: 0.21, 95%CI: 0.09–0.50), rectal diclofenac 100 mg (0.34, 0.18–0.65), sublingual GTN (0.34, 0.12–0.97), and rectal indomethacin 100 mg (0.49, 0.33–0.73) were all more efficacious than placebo in preventing PEP. The combination of rectal indomethacin and sublingual GTN had the highest surface under the cumulative ranking curves (SUCRA) probability of (92.2%) and was the best preventive strategy for moderate-to-severe PEP with a SUCRA probability of (89.2%).

CONCLUSION

Combination of rectal indomethacin 100 mg with sublingual GTN offered better prevention of PEP than when used alone and could alleviate the severity of PEP.

Does α-lipoic acid therapeutically effective against experimentally induced-acute pulpitis in rats?

The purpose of the study was to investigate the therapeutic effects of α-lipoic acid (ALA) on an induced-acute pulpitis model in rats. Twenty-four Wistar albino rats were randomly divided into three groups: control, induced-acute pulpitis (PULP) and PULP + ALA groups. In the PULP and PULP + ALA groups, the crowns of the maxillary left incisors were removed horizontally. All exposed pulp tissues were treated with 5 µL LPS solution. In the PULP + ALA group, the rats were treated intraperitoneally with a single dose of ALA (100 mg/kg). The rats were sacrificed 24 h after pulp injury, and the trunk blood and pulp samples were collected and then determined using ELISA assay kits. TNF-α, IL-1β, MMP-1 and MMP-2 levels in the serum and pulp tissues were considerably higher in the PULP group than the control group (p < 0.01-0.001). In the PULP + ALA group, TNF-α, IL-1β, MMP-1 and MMP-2 levels in the serum and pulp tissues decreased significantly compared to the PULP group (p < 0.05-0.001). ALA decreases pro-inflammatory mediators and proteolytic enzymes, which might relieve acute inflammation.

Proinflammatory cytokines inhibit thiamin uptake by human and mouse pancreatic acinar cells: involvement of transcriptional mechanism(s)

Thiamin (vitamin B1) plays critical roles in normal metabolism and function of all mammalian cells. Pancreatic acinar cells (PACs) import thiamin from circulation via specific carrier-mediated uptake that involves thiamin transporter-1 and -2 (THTR-1 and -2; products of SLC19A2 and SLC19A3, respectively). Our aim in this study was to investigate the effect(s) of proinflammatory cytokines on thiamin uptake by PACs. We used human primary (h)PACs, PAC 266-6 cells, and mice in vivo as models in the investigations. First, we examined the level of expression of THTR-1 and -2 mRNA in pancreatic tissues of patients with chronic pancreatitis and observed severe reduction in their expression compared with normal control subjects. Exposing hPACs and PAC 266-6 to proinflammatory cytokines (hyper IL-6, TNF-α, and IL-1β) was found to lead to a significant inhibition in thiamin uptake. Focusing on hyper-IL-6 (which also inhibited thiamin uptake by primary mouse PACs), the inhibition in thiamin uptake was found to be associated with significant reduction in THTR-1 and -2 proteins and mRNA expression as well as in activity of the SLC19A2 and SLC19A3 promoters; it was also associated with reduction in level of expression of the transcription factor Sp1 (which is required for activity of these promoters). Finally, blocking the intracellular Stat3 signaling pathway was found to lead to a significant reversal in the inhibitory effect of hyper IL-6 on thiamin uptake by PAC 266-6. These results show that exposure of PACs to proinflammatory cytokines negatively impacts thiamin uptake via (at least in part) transcriptional mechanism(s).NEW & NOTEWORTHY Findings of the current study demonstrate, for the first time, that exposure of pancreatic acinar cells to proinflammatory cytokines (including hyper IL-6) cause significant inhibition in vitamin B1 (thiamin; a micronutrient that is essential for normal cellular energy metabolism) and that this effect is mediated at the level of transcription of the thiamin transporter genes SLC19A2 and SLC19A3.

The early predictive role of complement C3 and C4 in patients with acute pancreatitis

Objective

The prognostic role of complement C3 and C4 in peripheral blood in early stage of acute pancreatitis (AP) is unknown. In this study, we aimed to evaluate the prognostic value of C3 and C4 in early stage of AP.

Methods

A total of 164 patients were enrolled in this study. The blood samples were collected within 24 hours after AP onset. We compared C3 and C4 levels in patients with different AP severity. The optimal cutoff value for them to predict severe AP (SAP) was determined by receiver operating characteristic (ROC) curve analysis.

Results

The reduction of C3 and C4 levels was observed. For prediction of MSAP and SAP, the AUC of C3 and C4 levels was 0.695 (95% CI: 0.612‐0.779) and 0.739 (95% CI: 0.657‐0.821). The cutoff value of C3 and C4 levels was 0.705 and 0.145 g/L, with the sensitivity of 0.612 and 0.735, and the specificity of 0.735 and 0.710. For prediction of SAP, the AUC of C3 and C4 levels was 0.749 (95% CI: 0.607‐0.891) and 0.766 (95% CI: 0.596‐0.936). The cutoff value of C3 and C4 levels was 0.400 and 0.125 g/L, with the sensitivity of 0.859 and 0.767, and the specificity of 0.600 and 0.786.

Conclusions

A marked change of complement C3 and C4 was observed in peripheral blood of patients with AP, suggesting the participation of complement system in the early phase of AP. C3 and C4 levels were sensitive and accurate in judging the severity of AP.

Pancreatic Blood Flow with Special Emphasis on Blood Perfusion of the Islets of Langerhans

The pancreatic islets are more richly vascularized than the exocrine pancreas, and possess a 5- to 10-fold higher basal and stimulated blood flow, which is separately regulated. This is reflected in the vascular anatomy of the pancreas where islets have separate arterioles. There is also an insulo-acinar portal system, where numerous venules connect each islet to the acinar capillaries. Both islets and acini possess strong metabolic regulation of their blood perfusion. Of particular importance, especially in the islets, is adenosine and ATP/ADP. Basal and stimulated blood flow is modified by local endothelial mediators, the nervous system as well as gastrointestinal hormones. Normally the responses to the nervous system, especially the parasympathetic and sympathetic nerves, are fairly similar in endocrine and exocrine parts. The islets seem to be more sensitive to the effects of endothelial mediators, especially nitric oxide, which is a permissive factor to maintain the high basal islet blood flow. The gastrointestinal hormones with pancreatic effects mainly influence the exocrine pancreatic blood flow, whereas islets are less affected. A notable exception is incretin hormones and adipokines, which preferentially affect islet vasculature. Islet hormones can influence both exocrine and endocrine blood vessels, and these complex effects are discussed. Secondary changes in pancreatic and islet blood flow occur during several conditions. To what extent changes in blood perfusion may affect the pathogenesis of pancreatic diseases is discussed. Both type 2 diabetes mellitus and acute pancreatitis are conditions where we think there is evidence that blood flow may contribute to disease manifestations. © 2019 American Physiological Society. Compr Physiol 9:799-837, 2019.

Association of a genetic polymorphism of IL1RN with risk of acute pancreatitis in a Korean ethnic group

BACKGROUND/AIMS

Several epidemiological studies have validated the association of interleukin gene polymorphisms with acute pancreatitis (AP) in different populations. However, there have been few studies in Asian ethnic groups. We aimed to investigate the relationships between inflammatory cytokine polymorphisms and AP as pilot research in a Korean ethnic group.

METHODS

Patients who had been diagnosed with AP were prospectively enrolled. DNA was extracted from whole blood, and DNA sequencing was subsequently performed. Single-nucleotide polymorphisms (SNPs) of the interleukin 1β (IL1B), interleukin 1 receptor antagonist (IL1RN), and tumor necrosis factor α (TNFA) genes of patients with AP were compared to those of normal controls.

RESULTS

Between January 2011 and January 2013, a total of 65 subjects were enrolled (40 patients with AP vs. 25 healthy controls). One intronic SNP (IL1RN -1129T>C, rs4251961) was significantly associated with the risk of AP (odds ratio, 0.304; 95% confidence interval, 0.095 to 0.967; p = 0.043). However, in our study, AP was not found to be associated with polymorphisms in the promoter regions of inflammatory cytokine genes, including IL1B (-118C>T, c47+242C>T, +3954C/T, and -598T>C) and TNFA (-1211T>C, -1043C>A, -1037C>T, -488G>A, and -418G>A).

CONCLUSION

IL1RN -1129T>C (rs4251961) genotypes might be associated with a significant increase of AP risk in a Korean ethnic group.

Effects of Cytokines and Other Inflammatory Mediators on Human Acute Pancreatitis

Most episodes of acute pancreatitis are mild, but severe disease complicated by multiple system organ failure develops in up to 20% of cases. In all patients with pancreatitis, the accumulation of leukocytes in pancreatic and extrapancreatic tissue, and the release of various mediators from them and other sites are important determinants of disease severity. Proinflammatory mediators, whose initial job is to limit the local damage, are released early in the disease. However, these mediators can exacerbate the severity of the pancreatitis when they continue to be elaborated in greater amounts or for longer periods than normal. When their actions are blocked or their release is inhibited, the severity of experimental pancreatitis and its associated mortality rate are less. This suggests the possibility that agents that inhibit the release and/or action of these mediators could be beneficial clinically.

Interleukin-6 is associated with chronic hyperglycemia and insulin resistance in patients after acute pancreatitis

BACKGROUND

Diabetes is a pervasive disease, with a mounting prevalence and burden on health care systems. Under this collective term of diabetes falls diabetes after diseases of the exocrine pancreas, a condition which was previously under-recognised and often mislabeled as type 2 diabetes mellitus and is now increasingly acknowledged as a stand-alone entity. However, there is a paucity of clinical studies investigating the underlying pathophysiology of diabetes after acute pancreatitis, the most frequent disease of the pancreas. This study aimed to investigate the role of adipocytokines in glucose metabolism after acute pancreatitis.

METHODS

This was a cross-sectional follow-up study of a patient cohort diagnosed with acute pancreatitis. Fasting venous blood samples were collected to analyse markers of glucose metabolism (fasting blood glucose, haemoglobin A1c, homeostasis model assessment (HOMA-IR) as a measure of insulin resistance) and adypocytokines (adiponectin, interleukin-6, leptin, monocyte chemoattractant protein-1, retinol binding protein-4, resistin, and tumor necrosis factor-α). Participants were categorized into two groups: normoglycemia after acute pancreatitis and chronic hyperglycemia after acute pancreatitis (CHAP). Binary logistic regression and linear regression analyses were used to investigate the association between each of the adipocytokines and markers of glucose metabolism. Potential confounders were adjusted for in multivariate analyses.

RESULTS

A total of 83 patients with acute pancreatitis were included, of whom 19 developed CHAP. Interleukin-6 was significantly associated with CHAP in both unadjusted and adjusted models (p = 0.030 and p = 0.018, respectively). Further, it was also significantly associated with HOMA-IR in both unadjusted and adjusted models (p = 0.029 and p = 0.037, respectively). Other adipocytokines were not significantly associated with markers of glucose metabolism.

CONCLUSION

Interleukin-6 appears to be implicated in the development of chronic hyperglycemia and insulin resistance in patients after acute pancreatitis. It may become a potential target in the prevention and early treatment of diabetes after diseases of the exocrine pancreas.

Suppression of acute pancreatitis by L-lysine in mice

BACKGROUND

Acute pancreatitis is an inflammatory disease caused by several factors such as viral infection, drugs, and diagnostic endoscopy. The aim of this study was to evaluate the potential protective or therapeutic effects of L-lysine on pancreatitis induced by L-arginine in mice.

METHODS

Four groups of mice (10 in each group) were assessed. Group I was the control. Animals in groups II-IV were injected intraperitoneally with L-arginine hydrochloride (400 mg/kg body weight [bw]) for 3 days. Group III animals were orally pre-treated with L-lysine (10 mg/kg bw), whereas group IV animals were orally post-treated with L-lysine (10 mg/kg bw). Serum samples were subjected to amylase, lipase, transaminase, and interleukin-6 (IL-6) assays. The pancreas was excised to measure the levels of malondialdehyde, nitric oxide, catalase, superoxide dismutase, reduced glutathione, and glutathione peroxidase.

RESULTS

Pre- or post-treatment with L-lysine led to significant decreases in the levels of malondialdehyde and nitric oxide, while significant enhancement was observed in the activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and glutathione (p < 0.001). However, the treatment potential of L-lysine was better as a protective agent than a therapeutic agent.

CONCLUSIONS

L-lysine treatment attenuates pancreatic tissue injury induced by L-arginine by inhibiting the release of the inflammatory cytokine IL-6 and enhance antioxidant activity. These effects may involve upregulation of anti-inflammatory factors and subsequent downregulation of IL6.

Effects of cyclooxygenase inhibition on insulin release and pancreatic islet blood flow in rats

OBJECTIVES

To examine the effects of inhibition of cyclooxygenase (COX) on islet hormone secretion in vitro and on pancreatic islet blood flow in vivo.

METHODS

Insulin release was measured in a static incubation system of islets isolated from Wistar-F rats after inhibition of COX-1 and COX-2 with SC 560 (COX-1), FR 122047 (COX-1), rofecoxib (COX-2), or indomethacin (both COX-1 and COX-2). In other rats organ blood flow values were measured with a microsphere technique during both normo- and hyperglycemia after administration of these enzyme inhibitors.

RESULTS

Serum insulin values were lower after pretreatment with a COX-1 inhibitor or a non-selective COX inhibitor in both control and glucose-injected rats in vivo, whereas COX-2 inhibition had no such effects. However, inhibition of COX had only minor effects on insulin release in vitro. Inhibition of COX affected neither total pancreatic nor islet blood flow in normoglycemic rats. Hyperglycemia caused an increase in both these flow values and in the duodenum. The increase in total pancreatic and duodenal blood flow was prevented by inhibition of COX-2 or non-selective COX inhibition. However, no effects on islet blood flow were seen after COX inhibition.

CONCLUSION

Inhibition of COX affects insulin release and blood glucose concentrations in vivo. However, COX inhibition has only minor effects on pancreatic islet blood flow, but prevents the glucose-induced increase in total pancreatic blood flow.

Anti-inflammatory effects of melatonin in a rat model of caerulein-induced acute pancreatitis

The purpose of our study was to evaluate the protective effect of melatonin in a rat model of caerulein-induced acute pancreatitis. For the induction of experimental acute pancreatitis, four subcutaneous injections of caerulein (20 mgkg–1 body weight) were given to Wistar rats at 2-h intervals. Melatonin was injected intraperitoneally (25 mg kg–1 body weight) 30 min before each caerulein injection. After 12 h, rats were sacrificed by decapitation. Blood and pancreas samples were collected and processed for serological and histopathological studies,respectively. Lipase, a-amylase, corticosterone, total antioxidant power and cytokines interleukin (IL)-1b, IL-4 and tumour necrosis factor(TNF)-a were determined using commercial kits. ANOVA and Tukey tests (P<0.05) were performed for the statistical analysis of the results.Results showed that the administration of melatonin reduced histological damage induced by caerulein treatment as well as the hyperamylasemia and hyperlipidemia. Corticosterone and antioxidant total power were also reverted to basal activities. Furthermore, melatonin pre-treatment reduced pro-inflammatory cytokines IL-1b and TNF-a and increased the serum levels of anti-inflammatory cytokine IL-4. In conclusion,the findings suggest that the protective effect of melatonin in caerulein-induced acute pancreatitis is mediated by the anti-inflammatory ability of this indolamine. Thus, melatonin may have a protective effect against acute pancreatitis.

Hypothermia induced by adenosine 5'-monophosphate attenuates injury in an L-arginine-induced acute pancreatitis rat model

BACKGROUND AND AIM

This study sought to investigate the effects of hypothermia induced by adenosine 5'-monophosphate (5'-AMP) on L-arginine (L-Arg)-induced acute pancreatitis in rats.

METHODS

The rats were divided into four groups: the control group, the acute pancreatitis group, the 5'-AMP pretreatment group, and the 5'-AMP posttreatment group. Rats in all groups, except for the control group, received two injections of 2.5 g/kg body weight (intraperitoneally) L-Arg, with an interval of 1 h between the injections. Subsequently, the rats were observed to assess whether hypothermia induced by 5'-AMP could effectively inhibit inflammation associated with L-Arg-induced acute pancreatitis in rats.

RESULTS

Hypothermia induced by 5'-AMP produced protective effects in our acute pancreatitis model. These effects exhibited the following manifestations: (i) a significant reduction in rat mortality rates; (ii) a significant decrease in the occurrence of pancreatic edema; (iii) significant reductions in serum amylase (P < 0.001), interleukin-6 (P < 0.001), interleukin-1β (P < 0.001) and tumor necrosis factor-α (P < 0.001); (iv) the significant inhibition of nuclear factor-κB (NF-κB) activation in rats that were pre- and posttreated with 5'-AMP compared with rats that were only injected with L-Arg; and (v) significant decreases in the occurrence of pancreatic interstitial edema, inflammatory cell infiltration, hemorrhage, and acinar cell necrosis.

CONCLUSIONS

Hypothermia induced by 5'-AMP could inhibit the acute inflammatory reaction and NF-κB activation associated with acute pancreatitis.

Associations between tumor necrosis factor alpha gene -238 G/A and -308 G/A polymorphisms and the risk of pneumoconiosis: update of a meta-analysis

OBJECTIVES

Tumor necrosis factor alpha (TNF-α) gene (-238 G/A [rs361525] and -308 G/A [rs1800629]) polymorphisms have been extensively studied in relation to various diseases, several epidemiologic studies have been performed to investigate the associations of TNF-α gene polymorphisms with pneumoconiosis; however, the results of these studies were not entirely consistent. In an effort to clarify earlier inconclusive results, we performed this meta-analysis of case-control genetic association studies.

METHODS

We identified eligible studies by searching the relevant databases, including PubMed, Embase, Web of Science, CBMdisc, CNKI, and Google Scholar, until February 15, 2013. Additionally, hand searching of the references of identified articles were performed. Heterogeneity and publication bias across studies were determined and the meta-analysis was performed by Stata 11.0.

RESULTS

Fourteen articles involving 20 studies were included in the final meta-analysis, covering a total of 1935 pneumoconiosis cases and 3753 controls. The results showed evidence for significant association between TNF-α gene -308 G/A polymorphism and pneumoconiosis risk, suggesting that TNF-α gene -308 A allele may be a risk factor for pneumoconiosis (for A allele vs. G allele: OR = 1.41, 95% CI = 1.10-1.81, p = 0.01; for A/A + G/A vs. G/G: OR = 1.52, 95% CI = 1.21-1.91, p < 0.01). For TNF-α gene -238 G/A polymorphism, no significant association was found between this genetic variation and pneumoconiosis risk.

CONCLUSIONS

This meta-analysis indicates that TNF-α gene -308 G/A polymorphism is associated with an increased pneumoconiosis risk.

Rhubarb attenuates the severity of acute necrotizing pancreatitis by inhibiting MAPKs in rats

AIM

To investigate the effect of rhubarb on MAPK activation in sodium taurocholate-induced pancreatitis in rats.

METHODS

All rats were randomly divided into three groups: control, acute pancreatitis (AP) and rhubarb treatment groups. The MAPK activation was detected by western blotting. The levels of TNFα and IL6 in serum were estimated by ELISA. The pathological changes of the pancreas were examined microscopically.

RESULTS

It was found that hemorrhage, exudates and infiltration of inflammatory cells in the pancreas were significantly less in the rhubarb group than in the AP group. In the AP group, the activation of MAPKs in pancreatic tissues was enhanced significantly at every time point compared with the control group and the levels of TNFα and IL6 were also increased. Rhubarb treatment markedly inhibited activation of MAPKs concomitantly with inhibition of TNFα and IL6 expression.

CONCLUSION

We suggest that rhubarb probably attenuates AP by inhibiting activation of MAPKs and expression of inflammatory mediators.

Inhibition of poly(ADP-ribose) polymerase attenuates acute kidney injury in sodium taurocholate-induced acute pancreatitis in rats

OBJECTIVES

The aim of our present study was to investigate the efficacy of poly(adenosine diphosphate-ribose) polymerase (PARP) inhibition in the development of acute kidney injury in an experimental model of severe acute pancreatitis induced by retrograde infusion of sodium taurocholate into the bile-pancreatic duct.

METHODS

Severity of pancreatitis was evaluated by serum amylase, lipase, tumor necrosis factor α, interleukin-1β, interleukin-6, and histological grading. The following markers of renal dysfunction and injury were measured: serum creatinine level, urea nitrogen level, myeloperoxidase activity, and histology. Activation of PARP, intercellular adhesion molecule-1, and P-selectin protein in the kidney was studied using Western blot analysis.

RESULTS

3-Aminobenzamide attenuated the following: (1) serum amylase, lipase, and renal dysfunction; (2) serum concentrations of proinflammatory cytokines; (3) pancreatic and renal pathological injury; (4) renal myeloperoxidase activity; and (5) activation of PARP, intercellular adhesion molecule-1, and P-selectin in the kidney.

CONCLUSIONS

Our results suggest that PARP activation may contribute to kidney injury and that PARP inhibitors may be beneficial in renal disorders associated with severe acute pancreatitis.

The role of sphingosine kinase 1 in patients with severe acute pancreatitis

OBJECTIVE

To investigate the role of sphingosine kinase 1 (SphK1)/sphingosine 1-phosphate (S1P) signaling in inflammatory response in severe acute pancreatitis (SAP).

BACKGROUND

SAP is an acute inflammatory process of the pancreas, which may lead to systemic inflammatory response syndrome and multiorgan dysfunction syndrome. SphK1 and its product S1P have been implicated in inflammatory response and various immune cell functions. However, the potential role for SphK1/S1P in inflammatory response in SAP is still unclear.

METHODS

Twenty-two patients with SAP were enrolled in this study. SphK1 expression on peripheral neutrophils, monocytes, and lymphocytes was evaluated by flow cytometry. SphK enzymatic activity in neutrophils and lymphocytes was measured using a radiometric assay. The expression of S1P1 and S1P3 mRNA was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The serum levels of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1β), and IL-6 were measured by ELISA.

RESULTS

The expression of SphK1 and SphK activity were markedly increased in peripheral immune cells in the early stage of SAP and then reduced in the restoration stage in the patients. Moreover, we found that the level of S1P3 mRNA in peripheral neutrophils and lymphocytes of SAP patients was significantly elevated in the early stage as compared with the healthy volunteers, and it reduced in the restoration period. SphK1 expression on human peripheral neutrophils, monocytes, and CD4(+) T lymphocytes were positively correlated with the APACHE (Acute Physiological and Chronic Health Evaluation) II scores in patients with SAP. The levels of serum proinflammatory cytokines including TNF-α, IL-1β, and IL-6 showed similar shifts with intracellular SphK1 expression in SAP patients.

CONCLUSIONS

The authors identified a link between the SphK1 expression on peripheral immune cells and the severity of SAP. Observations showed a possible immunomodulating role for SphK1/S1P signaling in inflammatory response in SAP, suggesting that regulation of SphK1/S1P pathway may represent novel targets in the treatment of SAP.

Association between tumor necrosis factor-alpha gene -308A/G polymorphism and the risk of acute pancreatitis: a meta-analysis

BACKGROUND

Epidemiologic studies have evaluated the association between tumor necrosis factor-alpha (TNF-α) gene -308A/G polymorphism and the risk of acute pancreatitis (AP), but the results are inconsistent. In order to derive a more precise estimation of the associations, a meta-analysis was performed.

MATERIALS AND METHODS

Systematic searches of electronic databases PubMed, Embase, and Web of Science, as well as hand searching of the references of identified articles, were performed. All case-control studies investigating the association between TNF-α gene -308A/G polymorphism and AP risk were included. The association was assessed by odds ratio (OR) with 95% confidence intervals (CIs). Publication bias was analyzed by Begg's funnel plot and Egger's regression test.

RESULTS

The initial search revealed 818 potentially eligible studies. Having read the title, abstract, or full text, we included six relevant studies in the final meta-analysis, which contained 1,006 AP cases and 782 controls. Overall, no significant association was found between TNF-α gene -308A/G polymorphism and AP risk when all studies were pooled into the meta-analysis (for A/A+A/G versus G/G: OR = 1.03, 95% CI = 0.83-1.28, P = 0.79; for A/A versus A/G+G/G: OR = 0.97, 95% CI = 0.65-1.45, P = 0.87; for A/A versus G/G: OR = 1.23, 95% CI = 0.79-1.91, P = 0.37; for A allele versus G allele: OR = 0.99, 95% CI = 0.83-1.18, P = 0.90). In addition, the similar results were obtained in the subgroup analysis based on the ethnicity and subtype of AP.

CONCLUSIONS

The present meta-analysis reveals that the TNF-α gene -308A/G polymorphism is not associated with AP risk. However, due to the small number of subjects included in analysis and the selection bias in some studies, the results should be interpreted with caution.

Polymorphisms in tumour necrosis factor alpha (TNFalpha) gene in patients with acute pancreatitis

Proinflammatory cytokines, such as tumour necrosis factor α (TNFα), play fundamental roles in the pathogenesis of acute pancreatitis (AP). The aim of this study was to determine if polymorphisms in the TNFα gene are associated with AP. Two polymorphisms located in the promoter region (positions −308 and −238) in TNFα gene were determined using polymerase chain reaction- (PCR-) restriction fragment length polymorphism (RFLP) methods in 103 patients with AP and 92 healthy controls. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using logistic regression analysis adjusted for age, sex, BMI and smoking. The frequencies of TNFα polymorphisms were both similar in patients with mild or severe pancreatitis, so were in pancreatitis patients and in controls. We suggest that both SNPs of TNFα are not genetic risk factor for AP susceptibility (OR = 1.63; 95% CI: 1.13−4.01 for TNFα⁻³⁰⁸ and OR = 0.86; 95% CI: 0.75−1.77 for TNFα⁻²³⁸).

Ethanol consumption as inductor of pancreatitis

Alcohol abuse is a major cause of pancreatitis, a condition that can manifest as both acute necroinflammation and chronic damage (acinar atrophy and fibrosis). Pancreatic acinar cells can metabolize ethanol via the oxidative pathway, which generates acetaldehyde and involves the enzymes alcohol dehydrogenase and possibly cytochrome P4502E1. Additionally, ethanol can be metabolized via a nonoxidative pathway involving fatty acid ethyl ester synthases. Metabolism of ethanol by acinar and other pancreatic cells and the consequent generation of toxic metabolites, are postulated to play an important role in the development of alcohol-related acute and chronic pancreatic injury. This current work will review some recent advances in the knowledge about ethanol actions on the exocrine pancreas and its relationship to inflammatory disease and cancer.

Evidence for cigarette smoke-induced oxidative stress in the rat pancreas

BACKGROUND/AIMS

Recent findings with a rodent model of cigarette smoke inhalation revealed a causal relationship between chronic exposure to cigarette smoke and the development of pancreatitis. The present study was conducted to ascertain whether cigarette smoke induces oxidative stress in the rat pancreas concurrently with inflammation.

METHODOLOGY

Rats (six per treatment group) were treated for 0, 3, 6, 9, or 12 weeks with cigarette smoke (0.7 mg/L). Pancreatic tissues were examined for histological and pathological alterations and serum for changes in interleukin-6 concentration. Pancreatic expression and localization of alpha-smooth muscle actin, transforming growth factor-beta1, and collagen-1 were determined as measures of progressive inflammation/fibrosis. Pancreatic superoxide dismutase and glutathione peroxidase activities and malondialdehyde content were measured as indices of oxidative stress.

RESULTS

Inflammatory cell infiltration and ductal hyperplasia were detected in pancreata after 12 weeks of treatment with cigarette smoke. The serum interleukin-6 concentration increased significantly and pancreatic glutathione peroxidase activity declined significantly after 12 weeks of treatment. No other significant changes were observed.

CONCLUSIONS

Pancreata of rats exposed chronically to cigarette smoke exhibit inflammation concurrently with suppression of glutathione peroxidase activity. These observations favor a role for oxidative stress in the induction of pancreatitis associated with chronic cigarette smoke inhalation.

The effect of hyperbaric oxygen on apoptosis and proliferation in severe acute pancreatitis

OBJECTIVES

This paper investigates the significance of apoptosis in severe acute pancreatitis (SAP) and the possible modulating effects of hyperbaric oxygen (HBO).

METHODS

Wistar rats (250-350 g) were induced with SAP by biliopancreatic infusion of 4% sodium taurocholate. Rats were randomized for HBO treatment. Pancreatic tissue was stained for apoptosis with immunohistochemistry (anti-CASPASE-3 antibody and TUNEL), and histopathology haematoxylin and eosin (H&E). Acini were stained for proliferation with an anti-KI67 antibody. ImageProPlus was used to quantify apoptosis and proliferation in acinar cells. Statistical analysis was performed with two-independent-sample t-test or non-parametric Mann-Whitney test.

RESULTS

In normal acini there is a low rate of apoptosis (0.165 +/- 0.157%, 0.181 +/- 0.168%, 0.130 +/- 0.298% in CASPASE-3, H&E and TUNEL, respectively) and proliferation (0.951 +/- 0.926%) (mean +/- standard deviation [SD]). When compared with normal, apoptosis (CASPASE-3: 1.28 +/- 1.12%, P= 0.008; 2.40 +/- 3.04%, P= 0.101; 1.23 +/- 0.87%, P= 0.091; H&E: 0.47 +/- 0.36%, P= 0.051; 0.69 +/- 0.63%, P= 0.001; 0.68 +/- 0.28%, P= 0; TUNEL: 1.08 +/- 1.42%, P= 0; 1.96 +/- 1.87%, P= 0; 2.36 +/- 2.26%, P= 0) and proliferation (1.96 +/- 1.89%, P= 0.187; 1.73 +/- 1.76%, P= 0.165; 1.36 +/- 1.40%, P= 0.571) were increased on days 1, 2 and 3 post-induction, respectively. In comparison with the untreated controls, HBO increased apoptosis on day 1 (CASPASE-3: 3.11 +/- 1.97%, P= 0.04; H&E: 0.97 +/- 0.76%, P= 0.005) and day 2 (TUNEL: 3.61 +/- 3.05%, P= 0.034). Treatment with HBO increased proliferation (3.04 +/- 3.14%, P= 0.519; 7.33 +/- 7.55%, P= 0.153) on days 2 and 3, respectively, compared with the untreated controls.

CONCLUSIONS

During SAP, acini apoptosis and proliferation were increased. Hyperbaric oxygen therapy may improve the condition of SAP by promoting apoptosis and proliferation.

Acute and sub-acute toxicological assessment of the aqueous seed extract of Persea americana mill (Lauraceae) in rats

The aqueous seed extract of Persea americana Mill (Lauraceae) is used by herbalists in Nigeria for the management of hypertension. As part of our on-going scientific evaluation of the extract, we designed the present study to assess its acute and sub-acute toxicity profiles in rats. Experiments were conducted to determine the oral median lethal dose (LD(50)) and other gross toxicological manifestations on acute basis. In the sub-acute experiments, the animals were administered 2.5 g/kg (p.o) per day of the extract for 28 consecutive days. Animal weight and fluid intake were recorded during the 28 days period. Terminally, kidneys, hearts, blood/sera were obtained for weight, haematological and biochemical markers of toxicity. Results show that the LD(50) could not be determined after a maximum dose of 10 g/kg. Sub-acute treatment with the extract neither affected whole body weight nor organ-to-body weight ratios but significantly increased the fluid intake (P < 0.0001). Haematological parameters and the levels of ALT, AST, albumin and creatinine were not significantly altered. However, the concentration of total proteins was significantly increased in the treated group. In conclusion, the aqueous seed extract of P. americana is safe on sub-acute basis but extremely high doses may not be advisable.

Acute biliary pancreatitis: diagnosis and treatment

Gallstones are the commonest cause of acute pancreatitis (AP), a potentially life-threatening condition, worldwide. The pathogenesis of acute pancreatitis has not been fully understood. Laboratory and radiological investigations are critical for diagnosis as well prognosis prediction. Scoring systems based on radiological findings and serologic inflammatory markers have been proposed as better predictors of disease severity. Early endoscopic retrograde cholangiopancreatography (ERCP) is beneficial in a group of patients with gallstone pancreatitis. Laparoscopic cholecystectomy with preoperative endoscopic common bile duct clearance is recommended as a treatment of choice for acute biliary pancreatitis. The timing of cholecystectomy, following ERCP, for biliary pancreatitis can vary markedly depending on the severity of pancreatitis.

Plasma concentrations of high-mobility group box protein 1, soluble receptor for advanced glycation end-products and circulating DNA in patients with acute pancreatitis

AIMS

High-mobility group box protein 1 (HMGB1), a late-acting proinflammatory cytokine, is secreted actively by inflammatory cells, and released passively from necrotic cells. From the aspect that both inflammation and necrosis are involved in the pathogenesis in acute pancreatitis, the aim of the study was a joint investigation of the plasma concentrations of HMGB1, its soluble receptor for advanced glycation end-products (sRAGE), and the circulating DNA as a marker of cell death.

METHODS

62 patients with acute pancreatitis (30 mild, 32 severe), 20 patients with sepsis, and 20 healthy controls were enrolled in the study. HMGB1 and sRAGE plasma levels were measured by means of ELISA. Plasma DNA concentrations were estimated by real-time quantitative PCR for the beta-globin gene.

RESULTS

The circulating HMGB1 level was significantly higher in patients with severe acute pancreatitis (13.33 +/- 2.11 ng/ml) than in healthy controls (0.161 +/- 0.03 ng/ml) or than in patients with mild pancreatitis (2.64 +/- 0.185 ng/ml). The plasma concentration of sRAGE was highest in patients with sepsis (2,210 +/- 252 pg/ml), while the levels of sRAGE correlated inversely with that of HMGB1 in patients with acute pancreatitis. The plasma DNA level was significantly elevated in patients with severe acute pancreatitis (2,206 +/- 452 ng/ml).

CONCLUSION

A complex study of the plasma levels of HMGB1, sRAGE and circulating DNA can be informative in evaluations of acute pancreatitis with different levels of severity.

The value of procalcitonin at predicting the severity of acute pancreatitis and development of infected pancreatic necrosis: systematic review

BACKGROUND

Many studies have evaluated serum levels of procalcitonin (PCT) as a predictor in the development of severe acute pancreatitis (SAP) and infected pancreatic necrosis (IPN). This study assesses the value of PCT as a marker of development of SAP and IPN.

METHODS

Medline, Web of Science, the Cochrane clinical trials register, and international conference proceedings were searched systematically for prospective studies, which evaluated the usefulness of PCT as a marker of SAP and IPN. The sensitivity, specificity, and diagnostic odds ratios (DORs) were calculated for each study, and the study quality and heterogeneity among the studies were evaluated.

RESULTS

Twenty-four of 59 studies identified were included in data extraction. The sensitivity and specificity of PCT for development of SAP were 0.72 and 0.86, respectively (area under the curve [AUC] = 0.87; DOR = 14.9; 95% confidence interval [CI] = 5.6-39.8), albeit with a significant degree of heterogeneity (Q = 28.56, P < .01). The sensitivity and specificity of PCT for prediction of infected pancreatic necrosis were 0.80 and 0.91 (AUC = 0.91; DOR = 28.3; 95% CI = 13.8-58.3) with no significant heterogeneity (Q = 7.83, P = .18). No significant heterogeneity was observed among the studies when only higher quality studies (AUC = 0.91; DOR = 30.7; 95% CI = 10.7-87.8) or studies that used a cutoff PCT level >0.5 ng/mL (AUC = 0.88, 32.8; 95% CI = 10.1-106.6) were included.

CONCLUSION

Serum measurements of PCT may be valuable in predicting the severity of acute pancreatitis and the risk of developing infected pancreatic necrosis.

Risk assessment in acute pancreatitis

BACKGROUND

Acute pancreatitis has a variable natural history and in a proportion of patients is associated with severe complications and a significant risk of death. The various tools available for risk assessment in acute pancreatitis are reviewed.

METHODS

Relevant medical literature from PubMed, Ovid, Embase, Web of Science and The Cochrane Library websites to May 2008 was reviewed.

RESULTS AND CONCLUSION

Over the past 30 years several scoring systems have been developed to predict the severity of acute pancreatitis in the first 48-72 h. Biochemical and immunological markers, imaging modalities and novel predictive models may help identify patients at high risk of complications or death. Recently, there has been a recognition of the importance of the systemic inflammatory response syndrome and organ dysfunction.

Cerulein pancreatitis: oxidative stress, inflammation, and apoptosis

Cerulein pancreatitis is similar to human edematous pancreatitis, manifesting with dysregulation of digestive enzyme production and cytoplasmic vacuolization, the death of acinar cells, edema formation, and infiltration of inflammatory cells into the pancreas. Reactive oxygen species are involved in nuclear factor-kappaB activation, cytokine expression, apoptosis and pathogenesis of pancreatitis. There is recent evidence that cerulein activates NADPH oxidase, which is a major source of reactive oxygen species during inflammation and apoptosis in pancreatic acinar cells. In addition, the Janus kinase/signal transducer and activator of transcription pathway has been suggested as being involved in inflammatory signaling in the pancreas. This review discusses the involvement of oxidative stress in inflammation and apoptosis in pancreatic acinar cells stimulated with cerulein as an in vitro model of pancreatitis.

Is there correlation between pancreatic enzyme and radiological severity in acute pancreatitis?

AIM: To investigate the correlation between the changes of pancreatic enzyme, the biochemical markers and the clinical results according to the Balthazar computer tomography (CT) grade.

METHODS: Between July 2004 and July 2005, we reviewed the charts of 119 patients who were admitted to our hospital with acute pancreatitis.

RESULTS: Eighty-three patients (69.7%) were male, and the mean age of the patients was 57 ± 15.7 years. The biliary pancreatitis patients had an older mean age. Forty-nine patients (41.1%) had biliary pancreatitis and forty-six (38.6%) had alcoholic pancreatitis. Group 3 patients had a longer duration of pain (2.51 ± 1.16 vs 3.17 ± 1.30 vs 6.56 ± 6.13, P < 0.001), a longer period of fasting (7.49 ± 4.65 vs 10.65 ± 5.54 vs 21.88 ± 13.81, P < 0.001) and a longer hospital stay (9.17 ± 5.34 vs 14.63 ± 8.65 vs 24.47 ± 15.52, P < 0.001) than the other groups. On the univariate analysis, the factors that affected the radiological grade were the leukocyte count at admission (P = 0.048), the hemoglobin (P = 0.016) and total bilirubin concentrations (P = 0.023), serum lipase (P = 0.009), the APACH II scores at admission (P = 0.017), the APACH II scores after 24 h (P = 0.031), the C-reactive protein (CRP) titer (P = 0.0001) and the follow up CRP titer (P = 0.003). But the CRP level (P = 0.001) and follow up CRP titer (P = 0.004) were only correlated with the radiological grade on multivariate analysis. According to the ROC curve, when we set the CRP cut off value at 83 mg/L, the likelihood ratio for a positive test was 3.84 and the likelihood ratio for a negative test was 0.26 in group 3.

CONCLUSION: In conclusion, our study suggests that the CRP with the radiological severity may be used to estimate the severity of acute pancreatitis.

Value of routine clinical tests in predicting the development of infected pancreatic necrosis in severe acute pancreatitis

OBJECTIVE

Fine-needle aspiration (FNA) is the procedure of choice for accurate diagnosis of infected necrosis. However, invasive procedures increase the risk of secondary pancreatic infection and the timing of FNA is still a matter for debate. Our objective was to assess the value of routine clinical tests to determine the minimal risk for infected necrosis, thereby optimizing timing and selection of patients for image-guided FNA.

MATERIAL AND METHODS

This prospective, non-randomized study comprised 90 patients with acute necrotizing pancreatitis. The data of 52 patients were used for discriminant function analysis to determine the differences between patients with infected necrosis and those with sterile necrosis. Cut-off points for variables were established using receiver operating characteristic (ROC) curve analysis and logistic regression was performed to determine the risk of infected necrosis. The clinical relevance of the defined diagnostic system was prospectively tested in a further 38 consecutive patients with acute necrotizing pancreatitis (ANP).

RESULTS

Discriminant function analysis showed that C-reactive protein (CRP) and white blood cell (WBC) values were significant discriminators between patients with sterile necrosis and those with infected necrosis. Cut-off values of 81 mg/l for CRP and 13 x 10(9)/l for WBC were established. The predicted risk for infected necrosis is approx. 1.4% if both tests are below the defined cut-off values. Consequently, we found FNA unnecessary in this subset of patients, unless otherwise indicated, as this invasive procedure per se carries a certain risk of bacterial contamination.

CONCLUSIONS

Routine clinical tests are helpful in diagnosing the development of infected necrosis. Based on the application of classification functions, the timing and selection of patients for image-guided FNA can be optimized.

Effect of hyperthermia on experimental acute pancreatitis

BACKGROUND

[corrected] Recent studies indicate that hyperthermia can change inflammatory mechanisms and protect experimental animals from deleterious effects of secretagogue-induced acute pancreatitis

AIM

To evaluate the effects of hyperthermia post-treatment on cerulein-induced acute pancreatitis in rats

METHODS

Twenty animals were divided in two groups: group I (n = 10), rats with cerulein-induced acute pancreatitis undergone hyperthermia, and group II (n = 10), animals with cerulein-induced acute pancreatitis that were kept normothermic. In all groups, amylase serum levels, histologic damage, vascular permeability and pancreatic water content were assessed. Acute pancreatitis was induced by administration of two cerulein injections (20 mcg/kg). A single dose of Evans' blue dye was administered along with the second dose of cerulein. All animals also received a subcutaneous injection of saline solution. After this process, animals undergone hyperthermia were heated in a cage with two 100 W lamps. Body temperature was increased to 39.5 degrees C and maintained at that level for 45 minutes. Normothermia rats were kept at room temperature in a second cage

RESULTS

Control animals had typical edema, serum amylase activity and morphologic changes of this acute pancreatitis model. Hyperthermia post-treatment ameliorated the pancreatic edema, whereas the histologic damage and the serum amylase level remained unchanged

CONCLUSIONS

The findings suggest a beneficial effect of the thermal stress on inflammatory edema in experimental acute pancreatitis.

Efeito da hipertermia na pancreatite aguda grave experimental

OBJETIVO: O objetivo deste estudo é avaliar os efeitos da hipertermia na pancreatite aguda (PA) grave experimental induzida por ácido taurocólico. MÉTODO: A PA grave foi induzida pela injeção retrógrada de ácido taurocólico a 2,5% ou 5% no ducto pancreático principal. Após a indução, os animais foram colocados numa gaiola contendo duas lâmpadas de 100 W. A temperatura corporal foi aumentada para 39,5ºC e mantida neste nível por 45 minutos. Foram estudados taxa de mortalidade em 72 horas, permeabilidade vascular no pâncreas, porcentagem de água no tecido pancreático, amilase sérica, histologia (edema, necrose acinar e infiltrado inflamatório) e níveis séricos de IL-6 e IL-10. RESULTADOS: Não houve alteração em nenhum dos parâmetros avaliados. CONCLUSÃO: Não há benefício da hipertermia na PA grave experimental induzida por ácido taurocólico.

Alleviation of cell damage in experimental ANP in rats by administration of chondroitin-sulfate reduces

In order to explore the effects of retrograde infusion of chondroitin-sulfate via the pancreatic duct on cytoprotection and attenuation of oxidative damage during acute necrotic pancreatitis (ANP), male Wistar rats were randomly divided into three groups: A, B (experimental groups) and C (sham operation, control group). The rats in group A was subjected to retrograde injection of 5% sodium taurocholate via the pancreatic duct, and those in group B received chondroitin-sulfate therapy after ANP induction. All rats in three groups were killed at 6 h. The levels of malondialdehyde (MAD), total superoxide dismutase (SOD), glutathione (GSH), adenosine triphosphate (ATP) and serum amylase (SAM) were measured. The morphologic changes in pancreatic tissues were observed. It was found that the level of SAM was increased in group A and group B, with corresponding pathological changes of ANP. The levels of ATP, GSH and SOD in group A were decreased markedly and MDN increased significantly as compared with those in group B (P<0.01). In group B, the histopathologic damage was attenuated to a certain extent in comparison to that in group A. It was concluded that endogenous antioxidants were significantly reduced and lipid peroxidation increased during ANP. Retrograde infusion of chondroitin-sulfate via pancreatic duct could alleviate the pancreatic cell damage as a sort of scavengers of oxygen free radicals.

Coagulation, platelets, and acute pancreatitis

Acute pancreatitis generates a complex cascade of immunological events that affect the pathogenesis and the progression of this disease. Several inflammatory mediators seem to play a critical role in the pathogenesis of pancreatitis and the subsequent inflammatory response. In turn, these mediators can influence hemostasis. Coagulation abnormalities occur in acute pancreatitis and are related to its severity. The contribution of blood platelets in the disturbed hemostasis in acute pancreatitis, although extensively studied, remains obscure. This article reviews the local and systemic implications of hemostatic abnormalities during acute pancreatitis. Furthermore, we discuss the prognostic value and the potential therapeutic implications of platelet activation and other hemostatic variables.

Effect of inhibition of prostaglandin E2 production on pancreatic infection in experimental acute pancreatitis

OBJECTIVE

Acute pancreatitis is one the important causes of systemic inflammatory response syndrome (SIRS). SIRS results in gut barrier dysfunction that allows bacterial translocation and pancreatic infection to occur. Indomethacin has been used to reduce inflammatory process and bacterial translocation in experimental models. The purpose of this study was to determine the effect of inhibition of prostaglandin E2 (PGE2) production on pancreatic infection.

MATERIALS AND METHODS

An experimental model of severe acute pancreatitis (AP) was utilized. The animals were divided into three groups: sham (surgical procedure without AP induction); pancreatitis (AP induction); and indomethacin (AP induction plus administration of 3 mg/kg of indomethacin). Serum levels of interleukin (IL)-6 and IL-10, PGE2, and tumor necrosis factor (TNF)-alpha were measured 2 h after the induction of AP. We analyzed the occurrence of pancreatic infection with bacterial cultures performed 24 h after the induction of AP. The occurrence of pancreatic infection (considered positive when the CFU/g was >105), pancreatic histologic analysis, and mortality rate were studied.

RESULTS

In spite of the reduction of IL-6, IL-10, and PGE2 levels in the indomethacin group, TNF-alpha level, bacterial translocation, and pancreatic infection were not influenced by administration of indomethacin. The inhibition of PGE2 production did not reduce pancreatic infection, histologic score, or mortality rate.

CONCLUSION

The inhibition of PGE2 production was not able to reduce the occurrence of pancreatic infection and does not have any beneficial effect in this experimental model. Further investigations will be necessary to discover a specific inhibitor that would make it possible to develop an anti-inflammatory therapy.

Polymorphism in the IL-8 gene, but not in the TLR4 gene, increases the severity of acute pancreatitis

BACKGROUND/AIM

Activated granulocytes and inflammatory mediators of the innate immune response play fundamental roles in the pathogenesis of acute pancreatitis. We studied whether polymorphisms of interleukin-8 (IL-8) and Toll-like receptor 4 (TLR4) genes correlate with the severity of acute pancreatitis.

METHODS

Patients with acute pancreatitis (n = 92) were grouped according to the severity of the disease on the basis of the Ranson scores. Healthy blood donors (n = 200) served as controls. The IL-8 -251 gene polymorphism was analyzed by amplification-refractory mutation system; the single-nucleotide polymorphisms (Asp299Gly and Thr399Ile) of TLR4 were investigated by using a real-time polymerase chain reaction method with melting point analysis.

RESULTS

The IL-8 A/T heterozygote mutant variants were detected with a significantly higher frequency among the patients with severe pancreatitis than among the healthy blood donors (60 vs. 42%; p = 0.0264, odds ratio = 2.071, 95% confidence interval = 1.101-3.896), while the frequency of the normal allelic genotype (TT) was higher among the patients with mild pancreatitis than in the group with severe pancreatitis (35 vs. 16%; p = 0.051, odds ratio = 2.917, 95% confidence interval = 1.089-7.811). There was no significant correlation between TLR4 polymorphisms and the acute pancreatitis itself, but nonsignificantly increased frequencies of Asp299Gly and Thr399Ile heterozygotes among patients with severe infected pancreatic necrosis could be observed relative to the patients with mild pancreatitis.

CONCLUSIONS

Determination of the frequency of IL-8 polymorphism in acute pancreatitis may be informative and may provide further evidence concerning the role of IL-8 in the severe form of this disease. The possible role of TLR4 polymorphism in the outcome of severe acute pancreatitis requires further investigations in a larger series of patients.

Suppression of IL-1beta expression by the Jak 2 inhibitor AG490 in cerulein-stimulated pancreatic acinar cells

Cerulein pancreatitis is similar to human edematous pancreatitis with dysregulation of the digestive enzyme production and cytoplasmic vacuolization, the death of acinar cells, edema formation, and an infiltration of inflammatory cells into the pancreas. Cytokines are up-regulated in pancreatic acinar cells stimulated with cerulein. In various cells and tissues, Janus kinase (Jak)/signal transducer and activator of transcription (Stat) pathway mediates inflammatory process. In the present study, we investigated whether the activation of Jak/Stat signaling mediates IL-1beta expression in pancreatic acinar AR42J cells stimulated with cerulein in vitro as well as the rats with cerulein pancreatitis in vivo using AG490, the Jak2 inhibitor. Activation of Jak2 and Stat3 were monitored by Western blot analysis for phosphorylated Jak2 and phosphorylated Stat3. mRNA expression and protein level of IL-1beta were determined by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbant assay (ELISA). Histological examination of pancreatic tissues were performed and serum IL-1beta levels of the rats were determined by ELISA. As a result, cerulein induced the activation of Jak2 and Stat3 as well as IL-1beta expression, which was inhibited by the treatment of AG490 in AR42J cells. In cerulein pancreatitis of the rats, edematous and inflammatory changes of the pancreas and increased serum levels of IL-1beta were suppressed by AG490 treatment. In conclusion, Jak2/Stat3 pathway may be the underlying mechanism in the pathogenesis of pancreatitis by inducing cytokines such as IL-1beta.

Inhibition of cyclooxygenase-2 in experimental severe acute pancreatitis

BACKGROUND

The standard treatment for acute pancreatitis (AP) is still based on supportive care. The search for a new drug that could change the natural history of the disease is a continuing challenge for many researchers. The aim of this study is to evaluate the effect of a cyclooxygenase-2 (COX-2) inhibitor on experimental AP in rats.

METHODS

The animals were divided into 2 groups: Group 1 (n = 30)-animals with taurocholate-induced AP treated with parecoxib (40 mg/kg). Group 2 (n = 30)-animals with taurocholate-induced AP that received saline. The COX-2 inhibitor (parecoxib) was injected immediately after AP induction, through the penis dorsal vein. The parameters evaluated were histology, serum levels of amylase, IL-6 and IL-10, and mortality rate.

RESULTS

The serum levels of IL-6 and IL-10 in the parecoxib-treated group were lower than the control group. The amylase serum levels and the mortality rate remained unchanged in the treated animals. Histologic morphology also was unaltered, except for fat necrosis, which was higher in parecoxib-treated rats.

CONCLUSION

Inhibition of Cox-2 decreases the systemic release of inflammatory cytokines, but has a poor effect on the direct pancreas injury caused by taurocholate.

Association between early systemic inflammatory response, severity of multiorgan dysfunction and death in acute pancreatitis

BACKGROUND

Mortality in patients with acute pancreatitis is associated with the number of failing organs and the severity and reversibility of organ dysfunction. The aim of this study was to assess the significance of early systemic inflammatory response syndrome (SIRS) in the development of multiorgan dysfunction syndrome (MODS) and death from acute pancreatitis.

METHODS

Data for all patients with a diagnosis of acute pancreatitis between January 2000 and December 2004 were reviewed. Serum C-reactive protein (CRP), Acute Physiology And Chronic Health Evaluation (APACHE) II scores and presence of SIRS were recorded on admission and at 48 h. Marshall organ dysfunction scores were calculated during the first week of presentation. Presence of SIRS and raised serum CRP levels on admission and at 48 h were correlated with the cumulative organ dysfunction scores in the first week.

RESULTS

A total of 759 patients with acute pancreatitis were identified, of whom 45 (5.9 per cent) died during the index admission. SIRS was identified in 162 patients on admission and was persistent in 138 at 48 h. The median (range) cumulative Marshall score in patients with persistent SIRS was significantly higher than that in patients in whom SIRS resolved and in those with no SIRS (4 (0-12), 3 (0-7) and 0 (0-9) respectively; P < 0.001). Thirty-five patients (25.4 per cent) with persistent SIRS died from acute pancreatitis, compared with six patients (8 per cent) with transient SIRS and four (0.7 per cent) without SIRS (P < 0.001). No correlation was observed between CRP level on admission and Marshall score (P = 0.810); however, there was a close correlation between CRP level at 48 h and Marshall score (P < 0.001).

CONCLUSION

Persistent SIRS is associated with MODS and death in patients with acute pancreatitis and is an early indicator of the likely severity of acute pancreatitis.

Epidural anaesthesia restores pancreatic microcirculation and decreases the severity of acute pancreatitis

AIM: To investigate the effect of epidural anaesthesia (EA) on pancreatic microcirculation during acute pancreatitis (AP).

METHODS: AP was induced by injection of sodium taurocholate into the pancreatic duct of Sprague-Dawley rats. To realize EA, a catheter was introduced into the epidural space between T7 and T9 and bupivacaine was injected. Microcirculatory flow was measured by laser Doppler flowmetry. Arterial blood gas analyses were performed. At the end of the experiment (≤ 5 h), pancreas was removed for histology. The animals were divided into three groups: Group 1 (n = 9), AP without EA; Group 2 (n = 4), EA without AP; and Group 3 (n = 6), AP treated by EA.

RESULTS: In Group 1, pancreatic microcirculatory flow prior to AP was 141 ± 39 perfusion units (PU). After AP, microcirculatory flow obviously decreased to 9 ± 6 PU (P < 0.05). Metabolic acidosis developed with base excess (BE) of - 14 ± 3 mmol/L. Histology revealed extensive edema and tissue necrosis. In Group 2, EA did not significantly modify microcirculatory flow. BE remained unchanged and histological analysis showed normal pancreatic tissue. In Group 3, AP initially caused a significant decrease in microcirculatory flow from 155 ± 25 to 11 ± 7 PU (P < 0.05). After initiation of EA, microcirculatory flow obviously increased again to 81 ± 31 PU (P < 0.05). BE was -6 ± 4 mmol/L, which was significantly different compared to Group 1 (P < 0.05). Furthermore, histology revealed less extensive edema and necrosis in pancreatic tissue in Group 3 than that in Group 1.

CONCLUSION: AP caused dramatic microcirculatory changes within the pancreas, with development of metabolic acidosis and tissue necrosis. EA allowed partial restoration of microcirculatory flow and prevented development of tissue necrosis and systemic complications. Therefore, EA should be considered as therapeutic option to prevent evolution from edematous to necrotic AP.

Local and systemic effects of hypertonic solution (NaCl 7.5%) in experimental acute pancreatitis

OBJECTIVES

Severe acute pancreatitis (AP) is characterized by hemodynamic alterations and a systemic inflammatory response, leading to a high mortality rate. Treatment of hemorrhagic shock with hypertonic saline solutions significantly reduces mortality through an improvement in the hemodynamic conditions and possibly by an anti-inflammatory effect. Therefore, hypertonic solutions could be effective in AP.

METHODS

Wistar rats were divided in 4 groups: group C, control, without AP; group NT, AP, without treatment; group NS, treatment with normal saline solution (NaCl 0.9%) 1 hour after AP; group HTS, treatment with hypertonic saline solution (NaCl 7.5%) 1 hour after AP. AP was induced by injection of 2.5% sodium taurocholate into the pancreatic duct. Mean arterial blood pressure (MAP) and heart rate were recorded at 0 and 2, 4, 24, and 48 hours after AP. After induction of AP, animals were killed at 2, 12, 24, and 48 hours for serum amylase, interleukin (IL)-6, and IL-10 analysis, pancreatic tissue culture and histologic analysis, oxidation and phosphorylation of liver mitochondria, pulmonary myeloperoxidase activity (MPO), and mortality study.

RESULTS

In animals of groups NS and NT, a significant decrease of MAP was observed 48 hours after AP (NS: 91 +/- 3 mm Hg; NT: 89 +/- 3 mm Hg) compared with baseline (C: 105 +/- 2 mm Hg) and to HTS group (HTS: 102 +/- 2 mm Hg; P < 0.05). In animals of group NT, NS, and HTS, serum IL-6 and IL-10 levels were significantly higher at 2 hours after AP compared with the control group. However, IL-6 levels at 12 hours after AP and IL-10 levels at 2 and 12 hours after AP were significant lower in group HTS compared with NS and NT groups (P < 0.05). In group HTS, a decrease of pulmonary MPO activity and of pancreatic infection was observed 24 hours after AP compared with NT and NS groups (P < 0.05). A significant reduction on pancreatic acinar necrosis and mitochondrial dysfunction was observed after 48 hours of AP in animals of group HTS compared with groups NT and NS (P < 0.05). A significant reduction on mortality was observed in HTS (0/14) compared with NS (6/17; 35%) and NT (7/20; 35%).

CONCLUSIONS

The administration of hypertonic saline solution in experimental AP attenuated hemodynamic alterations, decreased inflammatory cytokines, diminished systemic lesions and pancreatic acinar necrosis, prevented pancreatic infection, and reduced the mortality rate.

Pharmacological prevention and treatment of acute pancreatitis: where are we now?

Acute pancreatitis is a disease of increasing prevalence, unchanged mortality over many decades, and limited treatment strategies. Progress has been made in developing therapies that reduce the rate of endoscopic retrograde cholangiopancreatography (ERCP)-associated pancreatitis and in preventing infected pancreatic necrosis with intravenous carbapenems. Attempts at reducing pancreatic enzyme output or inhibiting the activity of digestive enzyme proteases have not yielded encouraging results - nor have anti-inflammatory strategies for the treatment of acute pancreatitis been found to be effective so far. Future therapeutic options that are presently being developed or under investigation attempt to restore pancreatic secretory function, interfere with inflammatory pathways in a more effective manner, or inhibit digestive enzyme proteases more selectively.

Delayed neutrophil apoptosis attenuated by melatonin in human acute pancreatitis

OBJECTIVES

This study evaluated the expression of neutrophil apoptosis and the effects of melatonin at different concentrations on delayed neutrophil apoptosis in different severities of acute pancreatitis in patients.

METHODS

The study population was comprised of 10 patients with severe acute pancreatitis (SAP) and 10 with mild acute pancreatitis (MAP). A total of 10 mL of blood was drawn 24 hours after the onset of the clinical disease for isolation and incubation of the human neutrophils with 4 different concentrations of melatonin. Neutrophil apoptosis activity, CD18 expression, and respiratory burst activity were assessed with flow cytometry 12 hours after incubation. Another group of neutrophils from a healthy control group was used (n = 6) for comparison.

RESULTS

Neutrophil apoptosis in patients with SAP is delayed compared with that of patients with MAP. Neutrophils from patients with SAP or MAP are functionally activated. Melatonin at concentrations of 10(-8), 10(-7), or 10(-6) M reverses the delayed process and enhances apoptosis activity in neutrophils in patients with MAP. Melatonin at concentrations of 10(-7) and 10(-6) M reverses the delayed process and increases apoptosis activity in neutrophils in patients with SAP. Neutrophils from patients with SAP and MAP showed significantly increased CD18 expression and respiratory burst activity. Melatonin at concentrations of 10(-7) or 10(-6) M reverses CD18 expression and respiratory burst activity in neutrophils in patients with SAP.

CONCLUSIONS

This study highlights the importance of neutrophil apoptosis in patients with SAP and raises the possibility of a therapeutic strategy. Study data show that melatonin promotes neutrophil apoptosis in human acute pancreatitis.

Severity of pancreatitis-associated gut barrier dysfunction is reduced following treatment with the PAF inhibitor lexipafant

The aim of the present study was to investigate the potential effect of treatment with a platelet-activating factor (PAF) antagonist, lexipafant (BB-882), on gut endothelial and epithelial barrier dysfunction and leukocyte recruitment in rats with acute pancreatitis. Severe acute pancreatitis was induced by the intraductal administration of 5% sodium taurodeoxycholate and pancreatitis-associated gut barrier dysfunction was characterized by increased exudation of radiolabelled albumin into the interstitium and alterations in bidirectional (over both the endothelial and epithelial barrier components) permeability of the intestine at the early stage of bile salt-induced acute pancreatitis. Levels of interleukin 1beta and 6, ileal and colonic myeloperoxidase (MPO) content, clearance of radiolabelled albumin from blood to the gut lumen or gut lumen to blood, and leakage of radiolabelled albumin to the ileum or colon were measured 3 and 12h after induction of acute pancreatitis. Treatment with lexipafant 30 min and 6h after pancreatitis reduced severity of pancreatitis-associated intestinal dysfunction, associated with a diminish in systemic concentrations of IL-1 and local leukocyte recruitment. The findings imply that PAF plays a critical role in the development of pancreatitis-associated gut barrier dysfunction and that PAF antagonist in some forms may represent potential candidates for future therapeutic intervention.

Synthetic protease inhibitor camostat prevents and reverses dyslipidemia, insulin secretory defects, and histological abnormalities of the pancreas in genetically obese and diabetic rats

BACKGROUND

Otsuka Long-Evans Tokushima Fatty (OLETF) rat, a model of type 2 diabetes, lacks the expression of cholecystokinin-1 receptor mRNA and exhibits inflammation and degeneration of the pancreas and eventually develops insulinopenic diabetes. Protease inhibitors are known to modulate inflammatory response and fibrosis as well as inhibit proteases activity.

AIM

To examine the effects of long-term treatment with camostat, a synthetic protease inhibitor, on metabolic and histopathological changes in the islets of OLETF rats.

METHOD

OLETF rats were fed either camostat-containing food (200 mg/100 g) from 12 or 28 weeks of age to 72 weeks of age, or fed standard rat diet.

RESULTS

Camostat-fed rats gained less weight or lost weight, although they consumed more food than the control rat when food intake was adjusted for body weight. Camostat reduced visceral adipose depots and fasting serum concentrations of triglyceride, free fatty acids, cholesterol, glucose, and insulin. Pancreatic insulin content in camostat-treated rats was significantly higher than in control rats. Immunohistochemistry revealed marked suppression of expressions of tumor necrosis factor alpha , interleukin 1 beta , interleukin 6, and alpha-smooth muscle actin in the islets of camostat-treated rats, compared with control rats. Histologically, disruption of the islets and pancreatic fibrosis were noted in control rats but not in camostat-fed rats.

CONCLUSION

Our findings suggest that camostat prevents and reverses obesity, hyperinsulinemia, hyperglycemia, and hyperlipidemia and markedly inhibits inflammation, fibrosis, and disruption of the islets in the genetically obese diabetic OLETF rats.

Polymorphism of the TNF-alpha, HSP70-2, and CD14 genes increases susceptibility to severe acute pancreatitis

OBJECTIVES

Proinflammatory cytokines and heat shock proteins play fundamental roles in the pathogenesis of acute pancreatitis. We studied whether polymorphisms of the tumor necrosis factor alpha (TNF-alpha), heat shock protein 70-2 (HSP70-2), and CD14 genes correlate with the severity of acute pancreatitis.

METHODS

Patients with acute pancreatitis (n = 77) of mixed etiology were grouped according to the severity of the disease on the basis of the Ranson scores. Healthy blood donors (n = 71) served as controls. TNF-alpha-308 polymorphism was determined by NcoI RFLP, HSP70-2 polymorphism by PstI RFLP, and CD14-159 polymorphism by melting point analysis.

RESULTS

There was a moderate increase in the frequency of the TNF1/2 genotype (P = 0.046) among patients with severe acute pancreatitis as compared with those with mild disease. A more significant increase was observed in the frequency of the HSP70-2 G allele between groups of patients with mild or severe pancreatitis (18.9% vs. 53%; P < 0.001). Conversely, the A/A genotype was markedly more frequent among the patients with mild pancreatitis (P < 0.0001). There was no significant correlation between CD14-159 promoter polymorphism and the severity of pancreatitis.

CONCLUSION

High frequencies of the HSP70-2 G and the TNF-alpha -308 A alleles were associated with risk of severe acute pancreatitis. Genotype assessments may be important prognostic tools to predict disease severity and the course of acute pancreatitis. Therefore, genotype assessments may also be used to guide treatment or to identify risk populations for severe acute pancreatitis.

Potential new therapies for the treatment of acute pancreatitis

The treatment of acute pancreatitis has remained virtually unchanged for the past 50 years, in large part due to a poor understanding of the initial intracellular events. Furthermore, there is a lack of knowledge regarding the mediator(s) responsible for the progression of the disease from local pancreatic inflammation to a systemic inflammatory disease, as well as the mediator(s) responsible for distant organ dysfunction and failure. With recent advances in the pathophysiology of pancreatitis, in particular the role of the inflammatory mediators interleukin-1 beta, tumour necrosis factor alpha and platelet-activating factor, the potential for new effective therapies has been realised. At present, a number of inflammatory mediator antagonists are being tested in humans, with the hope that we may soon develop a specific treatment for a disease, which thus far, has none.

Melatonin protects against pancreaticobiliary inflammation and associated remote organ injury in rats: role of neutrophils

Although the role of oxidative stress in acute pancreatitis (AP) has been studied in several animal models, little data are available regarding AP induced by pancreatic duct obstruction. We characterized the protective effects of melatonin on pancreaticobiliary inflammation and associated remote organ injury. In Sprague-Dawley rats, either the common pancreaticobiliary duct (PBDL; n = 28) or bile duct (BDL; n = 28) was ligated or a sham operation was applied (n = 14). Either melatonin (10 mg/kg) or vehicle (saline; 1 mL/kg) was administered intraperitoneally (i.p.) immediately before the surgery and twice a day until the rats were decapitated at 6 or 72 h. The pancreas, liver, kidneys and lungs were removed and tissue samples were stored for the determination of malondialdehyde (MDA) and glutathione (GSH) levels and myelopreoxidase activity. The results demonstrate that pathogenesis of acute obstructive pancreatitis involves not only the oxidative damage of the pancreatic and hepatic tissues, as assessed by increased MDA and reduced GSH levels, but the lungs and kidneys are also challenged by oxidant injury. Similarly, hepatic oxidative injury caused by cholestasis was also accompanied by pulmonary, renal and even pancreatic damage. The biochemical findings were also verified histologically. Melatonin, probably because of its free-radical scavenging and antioxidant activity, which involves an inhibitory effect on tissue neutrophil infiltration, protected all the affected tissues.