Acute Pancreatitis-Progress and Challenges: A Report on an International Symposium

Accelerating the Drug Delivery Pipeline for Acute and Chronic Pancreatitis-Knowledge Gaps and Research Opportunities: Overview Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

A workshop was sponsored by the Division of Digestive Diseases and Nutrition, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, on July 25, 2018, in Pittsburgh, Penn. The workshop was designed to bring together a multidisciplinary group of experts to accelerate the development of therapeutics for clinical application in inflammatory diseases of the exocrine pancreas. Three separate working groups (acute pancreatitis, recurrent acute pancreatitis, and chronic pancreatitis) were formed to address the needs, gaps, and opportunities. The working groups included patients with pancreatic diseases, pharmaceutical company leaders, basic scientists, clinical researchers, and representatives from the US Food and Drug Administration to assist with regulatory considerations and to identify the unmet needs, research targets, and opportunities to provide direction for successful development of therapeutic agents in these diseases. This article represents the summary of the overview presentations at the National Institute of Diabetes and Digestive and Kidney Diseases workshop including an ongoing drug trial in acute pancreatitis; a successful drug development network developed by the Cystic Fibrosis Foundation; and considerations for subject selection in drug trials, incorporating Food and Drug Administration guidelines on clinical trial design and clinical outcome measures. The summaries of each working group follow separately in accompanying articles.

Protective Role of TNIP2 in Myocardial Injury Induced by Acute Pancreatitis and Its Mechanism

BACKGROUND Aberrant regulation of nuclear factor-κB (NF-κB) and the signaling pathways that regulate its activity have been found to be involved in various pathologies, particularly cancers, as well as inflammatory and autoimmune diseases. Acute pancreatitis (AP) is a complex pathological process, depending on autodigestion caused by premature activation of zymogens. This study aimed to investigate the effect of high expression of TNIP2 gene on AP and AP-induced myocardial injury. MATERIAL AND METHODS To investigate the effect of TNIP2 on AP and AP-induced myocardial injury, we established an AP cell model and rat model. HE staining was applied for histological examination. ELISA was used to determine the level of pro-inflammatory cytokines (TNF-α and IL-6) and myocardial injury markers (LDH and CK-MB). QRT-PCR and Western blot analysis were performed to determine the mRNA and protein level of related genes, respectively. RESULTS We found that the protein level of TNIP2 was relatively higher in the normal AR42J cells. At 4 h after stimulating with cerulein, the protein level of TNIP2 decreased, reached a minimum at 8 h, and then gradually increased. We also found that TNIP2 was correlated with the activation of NF-κB in cerulein-stimulated AR42J cells, and TNIP2 over-expression inhibited the inflammatory response caused by cerulein. Moreover, our results suggest that TNIP2 over-expression relieved the cerulein-triggered inflammatory response and AP-induced myocardial injury in mice. CONCLUSIONS TNIP2 was shown to exert a protective effect on AP and AP-induced myocardial injury.

Human Pancreatic Acinar Cells: Proteomic Characterization, Physiologic Responses, and Organellar Disorders in ex Vivo Pancreatitis

Knowledge of the molecular mechanisms of acute pancreatitis is largely based on studies using rodents. To assess similar mechanisms in humans, we performed ex vivo pancreatitis studies in human acini isolated from cadaveric pancreata from organ donors. Because data on these human acinar preparations are sparse, we assessed their functional integrity and cellular and organellar morphology using light, fluorescence, and electron microscopy; and their proteome by liquid chromatography-tandem mass spectrometry. Acinar cell responses to the muscarinic agonist carbachol (CCh) and the bile acid taurolithocholic acid 3-sulfate were also analyzed. Proteomic analysis of acini from donors of diverse ethnicity showed similar profiles of digestive enzymes and proteins involved in translation, secretion, and endolysosomal function. Human acini preferentially expressed the muscarinic acetylcholine receptor M3 and maintained physiological responses to CCh for at least 20 hours. As in rodent acini, human acini exposed to toxic concentrations of CCh and taurolithocholic acid 3-sulfate responded with trypsinogen activation, decreased cell viability, organelle damage manifest by mitochondrial depolarization, disordered autophagy, and pathological endoplasmic reticulum stress. Human acini also secreted inflammatory mediators elevated in acute pancreatitis patients, including IL-6, tumor necrosis factor-α, IL-1β, chemokine (C-C motif) ligands 2 and 3, macrophage inhibitory factor, and chemokines mediating neutrophil and monocyte infiltration. In conclusion, human cadaveric pancreatic acini maintain physiological functions and have similar pathological responses and organellar disorders with pancreatitis-causing treatments as observed in rodent acini.

Differential susceptibility of mouse strains on pancreatic injury and regeneration in cerulein-induced pancreatitis

Acute pancreatitis (AP), a common disease, causes significant morbidity and mortality in clinical practice. Our objective of this study was to establish an experimental mouse AP model with cerulein treatment and to explore the susceptibility of mouse strains on the severity of pancreatic injury and the subsequent repair and regeneration. C57BL/6 and FVB/N mouse strains were used in this study. AP model was induced by six hourly intraperitoneal (i.p.) injections of cerulein dissolved in saline (100 μg/kg) administered on four consecutive days. Animals were sacrificed on 1, 3 and 7 days after last cerulein treatment, and then pancreas tissues were harvested and subjected to various histological, cellular and molecular analysis. Analyses of pancreatic injury and pancreatic amylase expression indicated that this cerulein-induced AP model was established successfully and that FVB/N mice showed more severe pancreatic injury and poor recovery compared to C57BL/6 strain. Analyses of myeloperoxidase (MPO), IL-1β and NF-κB showed that FVB/N strain exhibited more severe inflammation in the pancreas compared to C57BL/6 mice. Immunofluorescence analysis of activated caspase-3 and TUNEL assay indicated that the pancreas of FVB/N strain had more apoptosis compared to C57BL/6 mice. Analysis of Ki67 indicated FVB/N mice experienced more active proliferation compared to C57BL/6 strain. Collectively, these results demonstrated that there exists differential susceptibility on pancreatic injury and regeneration between FVB/N and C57BL/6 mice in the cerulein-induced AP.

Indomethacin inhabits the NLRP3 inflammasome pathway and protects severe acute pancreatitis in mice

Clinical studies have confirmed that indomethacin (Indo) can reduce the incidence and severity of post-endoscopicretrogradecholangio-pancreatography pancreatitis (PEP) effectively. However, the role of Indo on severe acute pancreatitis (SAP) is not clear. In the present study, we aimed to explore the effects of Indo treatment on SAP model induced by caerulein combined with lipopolysaccharide. After intraperitoneal injection of Indo in mice, both the severity of SAP and the serum levels of amylase, lipase, and proinflammatory cytokines were decreased. Furthermore, the mRNA and protein levels of NLRP3 inflammasome pathway (NLRP3,ASC and IL-1β) in pancreatic tissues were down-regulated. In vitro experiments, by isolating the pancreatic acinar cells (PACs) from mice, we found that Indo significantly reduced lactate dehydrogenase(LDH) excretion, increased the cell activity, and inhibited the NLRP3 inflammasome pathway of PACs. Taken together, our data showed that Indo could protect pancreatic acinar cell from injury by inhabiting NLRP3 pathway and decreased the severity of SAP accordingly.

Dynamic Measurement of Disease Activity in Acute Pancreatitis: The Pancreatitis Activity Scoring System

OBJECTIVES

Acute pancreatitis has a highly variable course. Currently there is no widely accepted method to measure disease activity in patients hospitalized for acute pancreatitis. We aimed to develop a clinical activity index that incorporates routine clinical parameters to assist in the measurement, study, and management of acute pancreatitis.

METHODS

We used the UCLA/RAND appropriateness method to identify items for inclusion in the disease activity instrument. We conducted a systematic literature review followed by two sets of iterative modified Delphi meetings including a panel of international experts between November 2014 and November 2015. The final instrument was then applied to patient data obtained from five separate study cohorts across Southern California to assess profiles of disease activity.

RESULTS

From a list of 35 items comprising 6 domains, we identified 5 parameters for inclusion in the final weighted clinical activity scoring system: organ failure, systemic inflammatory response syndrome, abdominal pain, requirement for opiates and ability to tolerate oral intake. We applied the weighted scoring system across the 5 study cohorts comprising 3,123 patients. We identified several distinct patterns of disease activity: (i) overall there was an elevated score at baseline relative to discharge across all study cohorts, (ii) there were distinct patterns of disease activity related to duration of illness as well as (iii) early and persistent elevation of disease activity among patients with severe acute pancreatitis defined as persistent organ failure.

CONCLUSIONS

We present the development and initial validation of a clinical activity score for real-time assessment of disease activity in patients with acute pancreatitis.

Early prediction of infected pancreatic necrosis secondary to necrotizing pancreatitis

To assess the association between the clinical parameters within 48 hours of admission and the occurrence of infected pancreatic necrosis (IPN) during the late phase of necrotizing pancreatitis (NP).All patients were divided into 2 groups, the IPN and non-IPN groups. The clinical data were retrospectively analyzed. Univariate and multivariate logistic regression analyses were performed to evaluate the relationship between clinical parameters and IPN secondary to NP. The performance of each independent variable was plotted by the receiver-operating characteristic (ROC) curve. Consequently, the cut-off level of each independent variable with its sensitivity and specificity was calculated.A total of 215 patients were enrolled in our study. Among them, 87 (40.5%) patients developed IPNs after a median of 13.5 (9.5-23.0) days from admission. Multivariate analysis indicated that the level of hematocrit (HCT) from 40% to 50% (P=.012, odds ratio (OR) = 2.407), HCT over 50% (P < .009, OR = 6.794), blood urea nitrogen (BUN) (P = .040, OR = 1.894), C-reactive protein (CRP) (P = .043, OR = 1.837), and procalcitonin (PCT) (P = .002, OR = 2.559) were independent risk factors of IPN secondary to NP. The ROC cures revealed that the area under the ROC (AUC) of the maximum level of HCT, BUN, CRP, and PCT within 48 hours of admission was 0.687, 0.620, 0.630, and 0.674 respectively. Furthermore, the combination of these 4 individual parameters contributes to a more preferable AUC of 0.789 with a sensitivity of 67.8% and specificity of 77.3%.The maximum levels of PCT, CRP, HCT, and BUN within 48 hours of admission are independent factors of IPN and their combination might accurately predict the occurrence of IPN secondary to NP.

Serological diagnosis and prognosis of severe acute pancreatitis by analysis of serum glycoprotein 2

BACKGROUND

Glycoprotein 2 (GP2), the pancreatic major zymogen granule membrane glycoprotein, was reported to be elevated in acute pancreatitis in animal models.

METHODS

Enzyme-linked immunosorbent assays (ELISAs) were developed to evaluate human glycoprotein 2 isoform alpha (GP2a) and total GP2 (GP2t) as specific markers for acute pancreatitis in sera of 153 patients with acute pancreatitis, 26 with chronic pancreatitis, 125 with pancreatic neoplasms, 324 with non-pancreatic neoplasms, 109 patients with liver/biliary disease, 67 with gastrointestinal disease, and 101 healthy subjects. GP2a and GP2t levels were correlated with procalcitonin and C-reactive protein in 152 and 146 follow-up samples of acute pancreatitis patients, respectively.

RESULTS

The GP2a ELISA revealed a significantly higher assay accuracy in contrast to the GP2t assay (sensitivity ≤3 disease days: 91.7%, specificity: 96.7%, positive likelihood ratio [LR+]: 24.6, LR-: 0.09). GP2a and GP2t levels as well as prevalences were significantly elevated in early acute pancreatitis (≤3 disease days) compared to all control cohorts (p<0.05, respectively). GP2a and GP2t levels were significantly higher in patients with severe acute pancreatitis at admission compared with mild cases (p<0.05, respectively). Odds ratio for GP2a regarding mild vs. severe acute pancreatitis with lethal outcome was 7.8 on admission (p=0.0222). GP2a and GP2t levels were significantly correlated with procalcitonin [Spearman's rank coefficient of correlation (ρ)=0.21, 0.26; p=0.0110, 0.0012; respectively] and C-reactive protein (ρ=0.37, 0.40; p<0.0001; respectively).

CONCLUSIONS

Serum GP2a is a specific marker of acute pancreatitis and analysis of GP2a can aid in the differential diagnosis of acute upper abdominal pain and prognosis of severe acute pancreatitis.

Serum Concentrations of Angiopoietin-2 and Soluble fms-Like Tyrosine Kinase 1 (sFlt-1) Are Associated with Coagulopathy among Patients with Acute Pancreatitis

In severe acute pancreatitis (SAP), systemic inflammation leads to endothelial dysfunction and activation of coagulation. Thrombotic disorders in acute pancreatitis (AP) include disseminated intravascular coagulation (DIC). Recently, angiopoietin-2 and soluble fms-like tyrosine kinase 1 (sFlt-1) were proposed as markers of endothelial dysfunction in acute states. Our aim was to assess the frequency of coagulation abnormalities in the early phase of AP and evaluate the relationships between serum angiopoietin-2 and sFlt-1 and severity of coagulopathy. Sixty-nine adult patients with AP were recruited: five with SAP, 15 with moderately severe AP (MSAP) and 49 with mild AP. Six patients were diagnosed with DIC according to International Society on Thrombosis and Haemostasis (ISTH) score. All patients had at least one abnormal result of routine tests of hemostasis (low platelet count, prolonged clotting times, decreased fibrinogen, and increased D-dimer). The severity of coagulopathy correlated with AP severity according to 2012 Atlanta criteria, bedside index of severity in AP and duration of hospital stay. D-dimers correlated independently with C-reactive protein and studied markers of endothelial dysfunction. Angiopoietin-2, D-dimer, and ISTH score were best predictors of SAP, while sFlt-1 was good predictor of MSAP plus SAP. In clinical practice, routine tests of hemostasis may assist prognosis of AP.

Disappearing portal venous gas in acute pancreatitis and small bowel ischemia

We report an usual case of hepatic portal venous gas (HPVG) in the setting of acute pancreatitis and small bowel ischemia. Interestingly, the HPVG disappeared within 2 hours of the original computed tomography scan, despite the patient having small bowel ischemia. The patient had a complicated clinical course, dying 62 days postadmission. This case highlights that HPVG in setting of acute pancreatitis and small bowel ischemia has a very high morbidity and mortality, requiring early detection and aggressive surgical management.

The Interplay between Inflammation, Coagulation and Endothelial Injury in the Early Phase of Acute Pancreatitis: Clinical Implications

Acute pancreatitis (AP) is an inflammatory disease with varied severity, ranging from mild local inflammation to severe systemic involvement resulting in substantial mortality. Early pathologic events in AP, both local and systemic, are associated with vascular derangements, including endothelial activation and injury, dysregulation of vasomotor tone, increased vascular permeability, increased leukocyte migration to tissues, and activation of coagulation. The purpose of the review was to summarize current evidence regarding the interplay between inflammation, coagulation and endothelial dysfunction in the early phase of AP. Practical aspects were emphasized: (1) we summarized available data on diagnostic usefulness of the markers of endothelial dysfunction and activated coagulation in early prediction of severe AP; (2) we reviewed in detail the results of experimental studies and clinical trials targeting coagulation-inflammation interactions in severe AP. Among laboratory tests, d-dimer and angiopoietin-2 measurements seem the most useful in early prediction of severe AP. Although most clinical trials evaluating anticoagulants in treatment of severe AP did not show benefits, they also did not show significantly increased bleeding risk. Promising results of human trials were published for low molecular weight heparin treatment. Several anticoagulants that proved beneficial in animal experiments are thus worth testing in patients.

Aspirin Protects against Acinar Cells Necrosis in Severe Acute Pancreatitis in Mice

Aspirin has a clear anti-inflammatory effect and is used as an anti-inflammatory agent for both acute and long-term inflammation. Previous study has indicated that aspirin alleviated acute pancreatitis induced by caerulein in rat. However, the role of aspirin on severe acute pancreatitis (SAP) and the necrosis of pancreatic acinar cell are not yet clear. The aim of this study was to determine the effects of aspirin treatment on a SAP model induced by caerulein combined with Lipopolysaccharide. We found that aspirin reduced serum amylase and lipase levels, decreased the MPO activity, and alleviated the histopathological manifestations of pancreas and pancreatitis-associated lung injury. Proinflammatory cytokines were decreased and the expression of NF-κB p65 in acinar cell nuclei was suppressed after aspirin treatment. Furthermore, aspirin induced the apoptosis of acinar cells by TUNEL assay, and the expression of Bax and caspase 3 was increased and the expression of Bcl-2 was decreased. Intriguingly, the downregulation of critical necrosis associated proteins RIP1, RIP3, and p-MLKL was observed; what is more, we additionally found that aspirin reduced the COX level of pancreatic tissue. In conclusion, our data showed that aspirin could protect pancreatic acinar cell against necrosis and reduce the severity of SAP. Clinically, aspirin may potentially be a therapeutic intervention for SAP.

Aspirin Protects against Acinar Cells Necrosis in Severe Acute Pancreatitis in Mice

Aspirin has a clear anti-inflammatory effect and is used as an anti-inflammatory agent for both acute and long-term inflammation. Previous study has indicated that aspirin alleviated acute pancreatitis induced by caerulein in rat. However, the role of aspirin on severe acute pancreatitis (SAP) and the necrosis of pancreatic acinar cell are not yet clear. The aim of this study was to determine the effects of aspirin treatment on a SAP model induced by caerulein combined with Lipopolysaccharide. We found that aspirin reduced serum amylase and lipase levels, decreased the MPO activity, and alleviated the histopathological manifestations of pancreas and pancreatitis-associated lung injury. Proinflammatory cytokines were decreased and the expression of NF-κB p65 in acinar cell nuclei was suppressed after aspirin treatment. Furthermore, aspirin induced the apoptosis of acinar cells by TUNEL assay, and the expression of Bax and caspase 3 was increased and the expression of Bcl-2 was decreased. Intriguingly, the downregulation of critical necrosis associated proteins RIP1, RIP3, and p-MLKL was observed; what is more, we additionally found that aspirin reduced the COX level of pancreatic tissue. In conclusion, our data showed that aspirin could protect pancreatic acinar cell against necrosis and reduce the severity of SAP. Clinically, aspirin may potentially be a therapeutic intervention for SAP.

Acute pancreatitis patient registry to examine novel therapies in clinical experience (APPRENTICE): an international, multicenter consortium for the study of acute pancreatitis

Background

We have established a multicenter international consortium to better understand the natural history of acute pancreatitis (AP) worldwide and to develop a platform for future randomized clinical trials.

Methods

The AP patient registry to examine novel therapies in clinical experience (APPRENTICE) was formed in July 2014. Detailed web-based questionnaires were then developed to prospectively capture information on demographics, etiology, pancreatitis history, comorbidities, risk factors, severity biomarkers, severity indices, health-care utilization, management strategies, and outcomes of AP patients.

Results

Between November 2015 and September 2016, a total of 20 sites (8 in the United States, 5 in Europe, 3 in South America, 2 in Mexico and 2 in India) prospectively enrolled 509 AP patients. All data were entered into the REDCap (Research Electronic Data Capture) database by participating centers and systematically reviewed by the coordinating site (University of Pittsburgh). The approaches and methodology are described in detail, along with an interim report on the demographic results.

Conclusion

APPRENTICE, an international collaboration of tertiary AP centers throughout the world, has demonstrated the feasibility of building a large, prospective, multicenter patient registry to study AP. Analysis of the collected data may provide a greater understanding of AP and APPRENTICE will serve as a future platform for randomized clinical trials.

Management of acute pancreatitis in Japan: Analysis of nationwide epidemiological survey

Acute pancreatitis (AP) is an acute inflammatory disease of the exocrine pancreas. In Japan, nationwide epidemiological surveys have been conducted every 4 to 5 years by the Research Committee of Intractable Pancreatic Diseases, under the support of the Ministry of Health, Labour, and Welfare of Japan. We reviewed the results of the nationwide surveys focusing on the severity assessment and changes in the therapeutic strategy for walled-off necrosis. The severity assessment system currently used in Japan consists of 9 prognostic factors and the imaging grade on contrast-enhanced computed tomography. By univariate analysis, all of the 9 prognostic factors were associated with AP-related death. A multivariate analysis identified 4 out of the 9 prognostic factors (base excess or shock, renal failure, systemic inflammatory response syndrome criteria, and age) that were associated with AP-related death. Receiver-operating characteristics curve analysis showed that the area under the curve was 0.82 for these 4 prognostic factors and 0.84 for the 9 prognostic factors, suggesting the comparable utility of these 4 factors in the severity assessment. We also examined the temporal changes in treatment strategy for walled-off necrosis in Japan according to the 2003, 2007, and 2011 surveys. Step-up approaches and less-invasive endoscopic therapies were uncommon in 2003 and 2007, but became popular in 2011. Mortality has been decreasing in patients who require intervention for walled-off necrosis. In conclusion, the nationwide survey revealed the comparable utility of 4 prognostic factors in the severity assessment and the increased use of less-invasive, step-up approaches with improved clinical outcomes in the management of walled-off necrosis.