Acute pancreatitis: animal models and recent advances in basic research

Material basis and molecular mechanisms of Chaihuang Qingyi Huoxue Granule in the treatment of acute pancreatitis based on network pharmacology and molecular docking-based strategy

Objectives

This study aimed to analyze active compounds and signaling pathways of CH applying network pharmacology methods, and to additionally verify the molecular mechanism of CH in treating AP.

Materials and methods

Network pharmacology and molecular docking were firstly used to identify the active components of CH and its potential targets in the treatment of AP. The pancreaticobiliary duct was retrogradely injected with sodium taurocholate (3.5%) to create an acute pancreatitis (AP) model in rats. Histological examination, enzyme-linked immunosorbent assay, Western blot and TUNEL staining were used to determine the pathway and mechanism of action of CH in AP.

Results

Network pharmacological analysis identified 168 active compounds and 276 target proteins. In addition, there were 2060 targets associated with AP, and CH had 177 targets in common with AP. These shared targets, including STAT3, IL6, MYC, CDKN1A, AKT1, MAPK1, MAPK3, MAPK14, HSP90AA1, HIF1A, ESR1, TP53, FOS, and RELA, were recognized as core targets. Furthermore, we filtered out 5252 entries from the Gene Ontology(GO) and 186 signaling pathways from the Kyoto Encyclopedia of Genes and Genomes(KEGG). Enrichment and network analyses of protein-protein interactions predicted that CH significantly affected the PI3K/AKT signaling pathway, which played a critical role in programmed cell death. The core components and key targets showed strong binding activity based on molecular docking results. Subsequently, experimental validation demonstrated that CH inhibited the phosphorylation of PI3K and AKT in pancreatic tissues, promoted the apoptosis of pancreatic acinar cells, and further alleviated inflammation and histopathological damage to the pancreas in AP rats.

Conclusion

Apoptosis of pancreatic acinar cells can be enhanced and the inflammatory response can be reduced through the modulation of the PI3K/AKT signaling pathway, resulting in the amelioration of pancreatic disease.

Sodium taurocholate hydrate inhibits influenza virus replication and suppresses influenza a Virus-triggered inflammation in vitro and in vivo

Influenza A virus is an important respiratory pathogen that poses serious threats to human health. Owing to the high mutation rate of viral genes, weaker cross-protection of vaccines, and rapid emergence of drug resistance, there is an urgent need to develop new antiviral drugs against influenza viruses. Taurocholic acid is a primary bile acid that promotes digestion, absorption, and excretion of dietary lipids. Here, we demonstrate that sodium taurocholate hydrate (STH) exhibits broad-spectrum antiviral activity against influenza strains H5N6, H1N1, H3N2, H5N1, and H9N2 in vitro. STH significantly inhibited the early stages of influenza A virus replication. The levels of influenza virus viral RNA (vRNA), complementary RNA (cRNA), and mRNA were specifically reduced in virus-infected cells following STH treatment. In vivo, STH treatment of infected mice alleviated clinical signs and reduced weight loss and mortality. STH also reduced TNF-α, IL-1β, and IL-6 overexpression. STH significantly inhibited the upregulation of TLR4 and the NF-kB family member p65, both in vivo and in vitro. These results suggest that STH exerts a protective effect against influenza infection via suppression of the NF-kB pathway, highlighting the potential use of STH as a drug for treating influenza infection.

Extracellular Vesicle ITGAM and ITGB2 Mediate Severe Acute Pancreatitis-Related Acute Lung Injury

Integrins expressed on extracellular vesicles (EVs) secreted by various cancers are reported to mediate the organotropism of these EVs. Our previous experiment found that pancreatic tissue of mice with severe cases of acute pancreatitis (SAP) overexpresses several integrins and that serum EVs of these mice (SAP-EVs) can mediate acute lung injury (ALI). It is unclear if SAP-EV express integrins that can promote their accumulation in the lung to promote ALI. Here, we report that SAP-EV overexpress several integrins and that preincubation of SAP-EV with the integrin antagonist peptide HYD-1 markedly attenuates their pulmonary inflammation and disrupt the pulmonary microvascular endothelial cell (PMVEC) barrier. Further, we report that injecting SAP mice with EVs engineered to overexpress two of these integrins (ITGAM and ITGB2) can attenuate the pulmonary accumulation of pancreas-derived EVs and similarly decrease pulmonary inflammation and disruption of the endothelial cell barrier. Based on these findings, we propose that pancreatic EVs can mediate ALI in SAP patients and that this injury response could be attenuated by administering EVs that overexpress ITGAM and/or ITGB2, which is worthy of further study due to the lack of effective therapies for SAP-induced ALI.

Macrophage membrane biomimetic drug delivery system: for inflammation targeted therapy

In recent years, there have been many exciting developments in the biomedical applications of the macrophage membrane bionic drug delivery system (MM-Bio-DDS). Macrophages, as an important immune cell, are involved in initiating and regulating the specific immune response of the body. Therefore, the inflammatory process related to macrophages is an important goal in the diagnosis and treatment of many diseases. In this review, we first summarise the different methods of preparation, characterisation, release profiles and natural advantages of using macrophages as a drug delivery system (DDS). Second, we introduce the processes of various chronic inflammatory diseases and the role of macrophages in them, specifically clarifying how the MM-Bio-DDS provides a wide and effective treatment for the targeted inflammatory site. Finally, based on the existing research, we propose the application prospect and existing challenges of the MM-Bio-DDS, especially the problems in clinical transformation, to provide new ideas for the development and utilisation of the MM-Bio-DDS in targeted drug delivery for inflammation and the treatment of diseases.

A Nano-Liposomal Formulation of Caffeic Acid Phenethyl Ester Modulates Nrf2 and NF-κβ Signaling and Alleviates Experimentally Induced Acute Pancreatitis in a Rat Model

The currently available management strategies for acute pancreatitis are inadequately effective which calls for exploration of new approaches to treat this condition. Caffeic acid phenethyl ester (CAPE) is a major bioactive constituent of honeybee propolis with promising therapeutic and preventive applications. However, its pharmaceutical potential and clinical use are hindered by its poor water solubility and limited plasma stability. In this study, we aimed to prepare, characterize and evaluate a CAPE-loaded nanoliposomal formulation to improve the efficacy of CAPE for the management of acute pancreatitis. The CAPE-loaded nanoliposomes (CAPE-loaded-NL) were prepared by a thin layer evaporation technique and were optimized using three edge activators. CAPE-loaded-NL were characterized for their vesicle size (VS), zeta potential (ZP), encapsulation efficiency (EE), polydispersity index (PDI), crystalline state and morphology. The protective effect of the optimal CAPE-loaded-NL was evaluated in a rat model of acute pancreatitis induced by administering a single intraperitoneal injection of L-ornithine. Oral pretreatment with CAPE-loaded-NL significantly counteracted ornithine-induced elevation in serum activities of pancreatic digestive enzymes and pancreatic levels of malondialdehyde, nuclear factor kappa B (NF-κB) p65, tumor necrosis factor-alpha, nitrite/nitrate, cleaved caspase-3 and myeloperoxidase activity. Moreover, pretreatment with CAPE-loaded-NL significantly reinstated the ornithine-lowered glutathione reductase activity, glutathione, nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 levels and ATP/ADP ratio, and potentiated the Bcl-2/Bax ratio in pancreatic tissue. CAPE-loaded-NL displayed superior antioxidant, anti-inflammatory and anti-apoptotic effects compared to free CAPE oral suspension and achieved a more potent correction of the derangements in serum amylase and pancreatic myeloperoxidase activities. The histological observations were in line with the biochemical findings. Our results suggest that CAPE-loaded-NL provide a promising interventional approach for acute pancreatitis mainly through the enhancement of the exerted antioxidant, anti-inflammatory and anti-apoptotic effects which may be mediated, at least in part, through modulation of Nrf2 and NF-κβ signaling.

Ketorolac and Predicted Severe Acute Pancreatitis: A Randomized, Controlled Clinical Trial

Objective: We evaluated the effect of ketorolac on reducing the severity of acute pancreatitis.Design and Setting: Randomized clinical trial performed in a University hospital.Participants: There were 56 adult patients, with predicted severe acute pancreatitis, randomly divided into two groups.Methods: The patients in the study group received intravenous ketorolac, 10 mg, three times daily from the time of enrollment for a maximum of 5 days, as needed, along with standard medical treatment. Primary outcome measure was the change in the serum level of high sensitive C-reactive protein (hs-CRP). Patients were also followed up in terms of hospitalization duration, need for intensive care unit (ICU), organ failure development, persistent organ failure, pancreatic necrosis, nutritional assessment, and mortality. The study continued to gather clinical follow-up information up to 4 months.Results: Serum level of hs-CRP was significantly lower in the ketorolac group compared with the control group on days 3, 4, and 5. There were no significant differences in organ failure, pseudocyst formation, acute necrotic collection, mortality, and ICU transfer between groups. Days of hospitalization were significantly lower in the study group. The feeding start time was significantly shorter in the study group with no need for tube feeding in the ketorolac group. Frequency of NPO (not per oral) was significantly lower in the ketorolac group.Conclusion: The use of ketorolac may improve feeding outcomes and shorten length of hospitalization in predicted severe acute pancreatitis.

Hypertriglyceridemia Acute Pancreatitis: Animal Experiment Research

In recent years, the number of acute pancreatitis cases caused by hypertriglyceridemia has increased gradually, which has caught the attention of the medical community. However, because the exact mechanism of hypertriglyceridemic acute pancreatitis (HTG-AP) is not clear, treatment and prevention in clinical practice face enormous challenges. Animal models are useful for elucidating the pathogenesis of diseases and developing and testing novel interventions. Therefore, animal experiments have become the key research means for us to understand and treat this disease. We searched almost all HTG-AP animal models by collecting many studies and finally collated common animals such as rats, mice and included some rare animals that are not commonly used, summarizing the methods to model spontaneous pancreatitis and induce pancreatitis. We sorted them on the basis of three aspects, including the selection of different animals, analyzed the characteristics of different animals, different approaches to establish hypertriglyceridemic pancreatitis and their relative advantages and disadvantages, and introduced the applications of these models in studies of pathogenesis and drug therapy. We hope this review can provide relevant comparisons and analyses for researchers who intend to carry out animal experiments and will help researchers to select and establish more suitable animal experimental models according to their own experimental design.

CaMK II Inhibition Attenuates ROS Dependent Necroptosis in Acinar Cells and Protects against Acute Pancreatitis in Mice

As a calcium-regulated protein, CaMK II is closely related to cell death, and it participates in the development of pathological processes such as reperfusion injury, myocardial infarction, and oligodendrocyte death. The function of CaMK II activation in acute pancreatitis (AP) remains unclear. In our study, we confirmed that the expression of p-CaMK II was increased significantly and consistently in injured pancreatic tissues after caerulein-induced AP. Then, we found that KN93, an inhibitor of CaMK II, could mitigate the histopathological manifestations in pancreatic tissues, reduce serum levels of enzymology, and decrease oxidative stress products. Accordingly, we elucidated the effect of KN93 in vitro and found that KN93 had a protective effect on the pancreatic acinar cell necroptosis pathway by inhibiting the production of ROS and decreasing the expression of RIP3 and p-MLKL. In addition, we identified the protective effect of KN93 on AP through another mouse model induced by pancreatic duct ligation (PDL). Together, these data demonstrated that CaMK II participates in the development of AP and that inhibiting CaMK II activation could protect against AP by reducing acinar cell necroptosis, which may provide a new idea target for the prevention and treatment of AP in the clinic.

Wedelolactone alleviates acute pancreatitis and associated lung injury via GPX4 mediated suppression of pyroptosis and ferroptosis

Acute pancreatitis (AP) is an inflammatory disorder associated with multiple organ failure. Pyroptosis and ferroptosis are two newly recognized cell death, and whether pyroptosis and ferroptosis are involved in AP remain largely elusive. The nature compound Wedelolactone (Wed) exhibits strong anti-inflammatory and antioxidant activities, the present study aims to investigate the effect of Wed on AP and unravel whether Wed could protect against AP and relevant lung injury against pyroptosis and ferroptosis. Our results showed that the pyroptosis inhibitor disulfiram or ferroptosis inhibitor ferrostatin-1 significantly alleviated AP and associated lung injury in the taurocholate or caerulein-induced murine AP model. Administration with Wed ameliorated AP and lung injury as evidenced by improved pathological injuries, reduced serum pancreatic digestive enzymes, and proinflammatory cytokines. The in vivo and in vitro data demonstrated that Wed broadly inhibited caspase1/caspase11 activation, reduced mature interleukin-1β (IL-1β) and N-terminal domain of gasdermin D (GSDMD-N) level. The oxidative stress and lipid peroxidation were also suppressed along with the up-regulation of the ferroptosis antagonism marker glutathione peroxidase-4 (GPX4) in Wed treatment group. Wed promoted the transcriptional activity and the selenium sensitivity of GPX4. Moreover, the protective effects of Wed in caerulein-stimulated pancreatic acinar cells were markedly abrogated by the down-regulation of GPX4. Collectively, our data suggest that pyroptosis and ferroptosis play crucial roles in AP. Wed mitigated AP and associated lung injury via GPX4 mediated suppression of pyroptosis and ferroptosis.

Mesenchymal stromal cell therapy for pancreatitis: Progress and challenges

Pancreatitis is a common gastrointestinal disease with no effective therapeutic options, particularly for cases of severe acute and chronic pancreatitis (CP). Mesenchymal stromal cells (MSCs) are multipotent cells with diverse biological properties, including directional migration, paracrine, immunosuppressive, and antiinflammatory effects, which are considered an ideal candidate cell type for repairing tissue damage caused by various pathogenies. Several researchers have reported significant therapeutic efficacy of MSCs in animal models of acute and CP. However, the specific underlying mechanisms are yet to be clarified and clinical application of MSCs as pancreatitis therapy has rarely been reported. This review mainly focuses on the potential and challenges in clinical application of MSCs for treatment of acute and CP, along with discussion of the underlying molecular mechanisms.

The Role of Mesenchymal Stem Cells with Ascorbic Acid and N-Acetylcysteine on TNF-α, IL 1β, and NF-κβ Expressions in Acute Pancreatitis in Albino Rats

Severe acute pancreatitis (SAP) is a necrotic pancreatic inflammation associated with high mortality rate (up to 70%). Bone marrow (BM) mesenchymal stem cells (MSCs) have been investigated in pancreatic cellular regeneration, but still their effects are controversial. Therefore, the present study is aimed at examining the enrichment of the stem cells with ascorbic acid (AA) and N-acetylcysteine (NAC) and explore their combined action on the expression of the inflammatory cytokines: interleukin 1β (IL 1β), tumor necrosis factor-α (TNF-α), and nuclear factor-κβ (NF-κβ). A total of twenty adult male Sprague-Dawley albino rats were divided into four groups: the control group, cerulein group (to induce acute pancreatitis), BM-MSCs group, and combined BM-MSCs with AA and NAC group. Homing and proliferation of stem cells were revealed by the appearance of PKH26-labelled BM-MSCs in the islets of Langerhans. AA and NAC combination with BM-MSCs (group IV) was demonstrated to affect the expression of the inflammatory cytokines: IL 1β, TNF-α, and NF-κβ. In addition, improvement of the biochemical and histological parameters is represented in increasing body weight, normal blood glucose, and insulin levels and regeneration of the islet cells. Immunohistochemical studies showed an increase in proliferating cell nuclear antigen (PCNA) and decrease in caspase-3 reactions, detected markedly in group IV, after the marked distortion of the classic pancreatic lobular architecture was induced by cerulein. It could be concluded that treatment with BM-MSCs combined with antioxidants could provide a promising therapy for acute pancreatitis and improve the degeneration, apoptosis, necrosis, and inflammatory processes of the islets of Langerhans. TNF-α, IL 1β, and NF-κβ are essential biomarkers for the evaluation of MSC regenerative effectiveness.

Role of Bile Acids and Bile Salts in Acute Pancreatitis: From the Experimental to Clinical Studies

ABSTRACT

Acute pancreatitis (AP) is one of the most common gastroenterological disorders leading to hospitalization. It has long been debated whether biliary AP, about 30% to 50% of all cases, is induced by bile acids (BAs) when they reach the pancreas via reflux or via the systemic blood circulation.Besides their classical function in digestion, BAs have become an attractive research target because of their recently discovered property as signaling molecules. The underlying mechanisms of BAs have been investigated in various studies. Bile acids are internalized into acinar cells through specific G-protein-coupled BA receptor 1 and various transporters. They can further act via different receptors: the farnesoid X, ryanodine, and inositol triphosphate receptor. Bile acids induce a sustained Ca2+ influx from the endoplasmic reticulum and release of Ca2+ from acidic stores into the cytosol of acinar cells. The overload of intracellular Ca2+ results in mitochondrial depolarization and subsequent acinar cell necrosis. In addition, BAs have a biphasic effect on pancreatic ductal cells. A more detailed characterization of the mechanisms through which BAs contribute to the disease pathogenesis and severity will greatly improve our understanding of the underlying pathophysiology and may allow for the development of therapeutic and preventive strategies for gallstone-inducedAP.

Association between biliary tree manipulation and outcome in dogs undergoing cholecystectomy for gallbladder mucocele: A multi-institutional retrospective study

OBJECTIVE

To determine whether catheterization of the common bile duct (CBD) is associated with outcome in dogs undergoing cholecystectomy for gallbladder mucocele and to determine whether this association is modified by the catheterization method.

STUDY DESIGN

Multi-institutional retrospective cohort study.

ANIMALS

Dogs (n = 252) that underwent cholecystectomy for gallbladder mucocele.

METHODS

Dogs were identified via electronic medical record review at four veterinary teaching hospitals. Baseline dog characteristics, surgical findings, and methods including normograde vs retrograde CBD catheterization, intraoperative outcomes, and postoperative outcomes and complications were recorded. Variables were compared between dogs with and without catheterization.

RESULTS

Catheterized dogs had higher American Society of Anesthesiologists scores (P = .04), higher total bilirubin (P = .01), and were more likely to have dilated CBD at the time of surgery (P < .01). Incidence of major and minor intraoperative complications was similar between the two groups. Surgical time was longer for the catheterized group (P = .01). The overall incidence of postoperative complications was similar between the groups; however, postoperative pancreatitis was associated with performing CBD catheterization (P = .01). This association was retained as an independent association in a multivariable model that addressed baseline group differences (P = .04). Likelihood of developing postoperative pancreatitis was not different between normograde and retrograde catheterization (P = .57).

CONCLUSION

Catheterization of the CBD was associated with development of postoperative pancreatitis. This was not influenced by the method of catheterization.

CLINICAL SIGNIFICANCE

The requirement for catheterization of the CBD during open cholecystectomy in dogs should be carefully considered, particularly in dogs without evidence of biliary obstruction because the procedure may induce postoperative pancreatitis.

Heparanase in Acute Pancreatitis

Acute pancreatitis (AP) is one of the most common diseases in gastroenterology, affecting 2% of all hospitalized patients. Nevertheless, neither the etiology nor the pathophysiology of the disease is fully characterized, and no specific or effective treatment has been developed. Heparanase (Hpa) is an endoglycosidase that cleaves heparan sulfate (HS) side chains of heparan sulfate proteoglycans (HSPGs) into shorter oligosaccharides, activity that is highly implicated in cell invasion associated with cancer metastasis and inflammation. Given that AP is a typical inflammatory disease, we investigated whether Hpa plays a role in AP. Our results provide keen evidence that Hpa expression and activity are significantly increased following cerulein-induced AP in wild type mice. In parallel to the classic manifestations of AP, namely elevation of amylase and lipase levels, pancreas edema and inflammation as well as induction of cytokines and signaling molecules, have been detected in this experimental model of the disease. Noteworthy, these features were far more profound in transgenic mice overexpressing heparanase (Hpa-Tg), suggesting that these mice can be utilized as a model system to reveal the molecular mechanism by which Hpa functions in AP. Further support for the involvement of Hpa in the pathogenesis of AP emerged from our observation that treatment of experimental AP with PG545 or SST0001(= Ronepastat), two potent Hpa inhibitors, markedly attenuated the biochemical, histological and immunological manifestations of the disease. Hpa, therefore, emerges as a potential new target in AP, and Hpa inhibitors are hoped to prove beneficial in AP along with their promising efficacy as anti-cancer compounds.

Prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis with rectal non-steroidal anti-inflammatory drugs

Acute pancreatitis is the most common and feared adverse event associated with performance of endoscopic retrograde cholangiopancreatography (ERCP). Unremitting effort has been made for over 40 years to minimize the frequency and severity of this complication. Recently, the use of rectal non-steroidal anti-inflammatory drugs (NSAIDs) have opened a new era for its prevention. This review focuses on the role of NSAIDs in pancreatitis, the pharmacokinetics of these agents, and summarizes the results of clinical trials with rectal NSAIDs alone and combination regimens in the prevention of post-ERCP pancreatitis.

Protective Effects of Bone Marrow-Derived Mesenchymal Stem Cells on Insulin Secretion and Inflammation in the Treatment of Severe Acute Pancreatitis in Rats

OBJECTIVE

The present study aims to demonstrate the protective effect of bone marrow mesenchymal stem cells (bmMSCs) on transplanted islets and its potential therapeutic role of severe acute pancreatitis (SAP) in rat model.

MATERIALS AND METHODS

Mesenchymal stem cells (MSCs) were isolated from 6 male SD rats, and were identified. The Islets isolated from 20 SD rats were evenly and randomly divided into co-culture group, and basic culture group (control group), in which the islets were cultured in DMEM/F12 medium, so as to compare the insulin secretion and stimulation index. Severe AP was induced in SD rats by retrograde injection of sodium taurocholate. Ninety rats were randomly and evenly assigned into 5 groups: control group (healthy rats), SAP group, tail vein injection group, intraperitoneal injection group and combined injection (tail vein + intraperitoneal) group. Rats were sacrificed on day 1, 2, and 3. The pancreatic tissues and blood were collected. The plasma levels of IL-10, IL-1β, TNF-α, IL-6 were determined using ELISA. Pathologic changes of the pancreas were observed using HE staining, and the positioning of DAPI labeled bmMSCs in vivo were detected.

RESULTS

Insulin secretion and the stimulation index of co-culture group were significantly higher than those of basic culture group (P < .05), after 7 and 14 days of culture. Inflammation, edema, hemorrhage and necrosis in each model of pancreatitis were reduced significantly in BMMSCs injection group as compared to SAP group (P < .05). Infused BMMSCs through combined injection indicated improved outcome than that of tail-vein injection or intraperitoneal injection alone.

CONCLUSION

Co-culture of BMMSCs with transplanted islets prolongs the survival time of islets and maintains in vitro activity. In the rat model of SAP, combined injection of BMMSCs through tail vein and intraperitoneal significantly suppresses the inflammatory reaction and alleviates pancreatic injury in rat SAP model.

Chrm3 protects against acinar cell necrosis by stabilizing caspase-8 expression in severe acute pancreatitis mice model

Acinar cells in acute pancreatitis (AP) die through apoptosis and necrosis, the impacts of which are quite different. Early clinical interference strategies on preventing the progress of AP to severe acute pancreatitis (SAP) are the elimination of inflammation response and inhibition of necrosis. Muscarinic acetylcholine receptor M3 was encoded by Chrm3 gene. It is one of the best-characterized receptors of pancreatic β cells and regulates insulin secretion, but its function in AP remains unclear. In this study, we explored the function of Chrm3 gene in the regulation of cell death in l-arginine-induced SAP animal models. We found that Chrm3 was upregulated in pancreatitis, and we further confirmed the localization of Chrm3 resided in both pancreatic islets and acinar cell membranes. The reduction of Chrm3 decreased the pathological lesion of SAP and reduced amylase activities in serum. Consistently, Chrm3 can suppress acinar cells necrosis markedly, but has no effect on regulating apoptosis after l-arginine treatment. It was shown that Chrm3 attenuated acinar cells necrosis at least in part by stabilizing caspase-8. Thus, this study indicates that Chrm3 is critical participants in SAP, and regulation of Chrm3 expression might be a useful therapeutic strategy for preventing pathologic necrosis.

Glucose metabolism during tumorigenesis in the genetic mouse model of pancreatic cancer

AIM

More than 40% of pancreatic ductal adenocarcinoma (PDAC) patients have glucose intolerance or diabetes. The association has led to two hypotheses: PDAC causes diabetes or diabetes shares risk factors for the development of PDAC. In order to elucidate the relationship between diabetes and PDAC, we investigated the glucose metabolism during tumorigenesis in the LSL-KrasG12D/+; LSL-Trp53R172H/+; and Pdx-1-Cre (KPC) mouse, a genetically engineered model of PDAC.

METHODS

Male and female KPCs have been fed with standard diet (SD) or high-fat diet (HFD). The imaging-based 4-class tumor staging was used to follow pancreatic cancer development. Not fasting glycemia, 4-h fasting glycemia, insulin, C-peptide, glucose tolerance after OGTT and abdominal fat volume were measured during tumorigenesis.

RESULTS

PDAC development did not lead to an overt diabetic phenotype or to any alterations in glucose tolerance in KPC fed with SD. Consumption of HFD induced higher body weight/abdominal fat volume and worsened glucose homeostasis both in control CRE mice and only in early tumorigenesis stages of the KPC mice, excluding that the cancer development itself acts as a trigger for the onset of dysmetabolic features.

CONCLUSION

Our data demonstrate that carcinogenesis in KPC mice is not associated with paraneoplastic diabetes.

Effectiveness and therapeutic value of phytochemicals in acute pancreatitis: A review

BACKGROUND

Acute pancreatitis (AP) is an inflammatory disorder of the pancreas that can lead to local and systemic complications. Repeated attacks of AP can lead to chronic pancreatitis, which markedly increases the probability of developing pancreatic cancer. Although many researchers have attempted to identify the pathogenesis involved in the initiation and aggravation of AP, the disease is still not fully understood, and effective treatment is limited to supportive therapy.

METHODS

We aim to summarize available literature focused on phytochemicals (berberine, chlorogenic acid, curcumin, emblica officinalis, ellagic acid, cinnamtannin B-1, resveratrol, piperine and lycopene) and discuss their effectiveness and therapeutic value for improving AP.

RESULTS

This study is based on pertinent papers that were retrieved by a selective search using relevant keywords in PubMed and ScienceDirect databases.

CONCLUSIONS

Many phytochemicals hold potential in improving AP symptoms and may be a valuable and effective addition to standard treatment of AP. It has already been proven that the crucial factor for reducing the severity of AP is stimulation of apoptosis along with/or inhibition of necrosis. Supplementation of phytochemicals, which target the balance between apoptosis and necrosis can be recommended in ongoing clinical studies.

Ameliorative effect of certolizumab on experimentally induced acute necrotic pancreatitis in rats

OBJECTIVE

The effects of Certolizumab, a pegylated monoclonal antibody to tumor necrosis factor α, on experimentally induced acute pancreatitis (AP) were examined.

METHODS

Thirty-six Wistar Albino male rats were randomly divided into four groups. Group I was the control group and no medication administered to this group. Group II was the Certolizumab group, and 100 ml/kg serum physiologic administered into the biliopancreatic duct and a single dose of 10 μg Certolizumab was simultaneously administered intraperitoneally. Acute pancreatitis was induced with a retrograde injection of 3% Na taurocholate into the common biliopancreatic duct in the study (Group III) and treatment (Groups IV) groups. Rats were sacrificed 72 hours later. Serum amylase, lipase, lactate dehydrogenase activities, along with pancreatic histopathology, were examined.

RESULTS

Certolizumab treatment significantly decreased serum amylase, lipase, and LDH levels; histopathologically edema, hemorrhage, parenchymal necrosis, fat necrosis, and infiltration scores; immunohistochemically MDA, MPO, TNF-α and Caspase-3 activity.

CONCLUSION

The results support the idea that certolizumab might be beneficial for the severity of AP.

Obesity Aggravates Acute Pancreatitis via Damaging Intestinal Mucosal Barrier and Changing Microbiota Composition in Rats

Obesity may aggravate acute pancreatitis (AP) through damaging the intestinal mucosal barrier (IMB). The underlying mechanism remains unclear. This study was aimed to provide further data to clarify the mechanism. 48 rats were divided into 4 groups: 1) normal control (NC), chow-fed rats with sham operation, 2) no-obese rats with AP (NAP), chow-fed rats with taurocholate infusion, 3) obese control (OC), high-fat diet (HFD)-fed rats with sham operation, and 4) obese rats with AP (OAP), HFD-fed rats with taurocholate infusion. Pancreatic pathologic score (11.39 ± 1.76 vs. 14.11 ± 1.05, p = 0.005), intestinal permeability to FD4 (0.91 ± 0.25 μg/ml vs. 7.06 ± 3.67 μg/ml, p < 0.001), serum leptin (10.25 ± 5.59 ng/ml vs. 79.73 ± 38.44 ng/ml, p < 0.001) and ileal apoptosis (2.05 ± 0.73% vs. 4.53 ± 2.28%, p = 0.006) were significantly higher in OAP than in NAP group. The intestinal bacterial richness (Chao 1 and OTUs) was significantly lower in OAP than in NAP rats. The higher abundance of Proteobacteria and reduced proportions of intestinal Actinobacteria, Allobaculum and Barnesiella were detected in OAP group. Obesity may result in decreased intestinal leptin/ObR-b binding, distinct phylogenetic clusters of ileal bacterial communities, increased intestinal inflammatory injury and the insufficient intestinal epithelial cells proliferation during AP attack. Pancreatic injury was aggravated due to obesity associated dysfunction of IMB.

Concise review: The challenges and opportunities of employing mesenchymal stromal cells in the treatment of acute pancreatitis

To date only small animal models have been employed to assess the effect of mesenchymal stromal cell (MSC) therapy on acute pancreatitis (AP), the most common cause of hospitalization for gastrointestinal diseases worldwide. We outline the challenges inherent in the small animal models of AP. We also point to specific benefits afforded by the adoption of larger animal models. The potential for MSC therapeutics in the treatment of AP was recognized over a decade ago. With sharper focus on the form of AP and development of new MSC delivery routes in larger animals, we believe the challenge can be engaged.

Plasticity of differentiated cells in wound repair and tumorigenesis, part I: stomach and pancreas

For the last century or so, the mature, differentiated cells throughout the body have been regarded as largely inert with respect to their regenerative potential, yet recent research shows that they can become progenitor-like and re-enter the cell cycle. Indeed, we recently proposed that mature cells can become regenerative via a conserved set of molecular mechanisms ('paligenosis'), suggesting that a program for regeneration exists alongside programs for death (apoptosis) and division (mitosis). In two Reviews describing how emerging concepts of cellular plasticity are changing how the field views regeneration and tumorigenesis, we present the commonalities in the molecular and cellular features of plasticity at homeostasis and in response to injury in multiple organs. Here, in part 1, we discuss these advances in the stomach and pancreas. Understanding the extent of cell plasticity and uncovering its underlying mechanisms may help us refine important theories about the origin and progression of cancer, such as the cancer stem cell model, as well as the multi-hit model of tumorigenesis. Ultimately, we hope that the new concepts and perspectives on inherent cellular programs for regeneration and plasticity may open novel avenues for treating or preventing cancers.

Leptin alleviates intestinal mucosal barrier injury and inflammation in obese mice with acute pancreatitis

BACKGROUND/OBJECTIVES

Obesity is an independent risk factor for severe acute pancreatitis (AP). Leptin plays an important role in energy homeostasis. It has been reported that leptin might also participate in the regulation of the intestinal mucosal barrier and inflammatory response. This study aimed to evaluate the effects of leptin on the intestinal mucosal barrier and inflammatory injury in obese mice with AP.

SUBJECTS/METHODS

AP was induced in leptin-deficient (ob/ob) or wild type (WT) mice by peritoneal injection of caerulein. The animals were divided into 4 groups: WT mice with or without exogenous leptin injection and ob/ob mice with or without leptin treatment. The inflammatory scoring of the pancreas and intestine were evaluated. Intestinal permeability, ileal interleukin (IL)-6 and IL-1β, proliferation, apoptosis and intestinal expression levels of claudin-1 and occludin were measured.

RESULTS

Pancreatic pathologic scores (8.50 ± 0.96 vs. 3.78 ± 1.35, p < 0.001), pancreatic levels of IL-6 (8.34 ± 3.21 ng/mg vs. 4.99 ± 0.53 ng/mg, p = 0.022), intestinal oedema scores (2.25 ± 0.46 vs. 1.14 ± 0.69, p = 0.001) and intestinal permeability to FD4 (0.78 ± 0.06 μg/ml vs. 0.53 ± 0.11 μg/ml, p < 0.001) were significantly higher in ob/ob mice than those in WT mice. Leptin replacement in ob/ob mice greatly improved the intestinal permeability (FD4 0.66 ± 0.03 μg/ml, vs. 0.78 ± 0.06 μg/ml, p = 0.012), increased the ileal expression of claudin-1(1.07 ± 0.08 vs. 0.83 ± 0.07 relative densitometry, p = 0.001) and reduced intestinal IL-6 and IL-1β to levels comparable to those in WT mice. The pancreatic level of IL-6 in ob/ob mice treated with leptin was also significantly decreased relative to that of untreated ob/ob mice (4.45 ± 1.71 ng/mg vs. 8.34 ± 3.21 ng/mg, p = 0.010).

CONCLUSIONS

Obesity may aggravate intestinal inflammation and increase intestinal permeability under the condition of acute pancreatitis. Exogenous leptin supplementation was in favour of anti-inflammation and improvement of intestinal mucosal barrier.

Mesenchymal Stromal Cell Therapy for Pancreatitis: A Systematic Review

Background

Based on animal studies, adult mesenchymal stromal cells (MSCs) are promising for the treatment of pancreatitis. However, the best type of this form of cell therapy and its mechanism of action remain unclear.

Methods

We searched the PubMed, Web of Science, Scopus, Google Scholar, and Clinical Trials.gov websites for studies using MSCs as a therapy for both acute and chronic pancreatitis published until September 2017.

Results

We identified 276 publications; of these publications, 18 met our inclusion criteria. In animal studies, stem cell therapy was applied more frequently for acute pancreatitis than for chronic pancreatitis. No clinical trials were identified. MSC therapy ameliorated pancreatic inflammation in acute pancreatitis and pancreatic fibrosis in chronic pancreatitis. Bone marrow and umbilical cord MSCs were the most frequently administered cell types. Due to the substantial heterogeneity among the studies regarding the type, source, and dose of MSCs used, conducting a meta-analysis was not feasible to determine the best type of MSCs.

Conclusion

The available data were insufficient for determining the best type of MSCs for the treatment of acute or chronic pancreatitis; therefore, clinical trials investigating the use of MSCs as therapy for pancreatitis are not warranted.

Phytoceuticals in Acute Pancreatitis: Targeting the Balance between Apoptosis and Necrosis

Despite recent advances in understanding the complex pathogenesis of pancreatitis, the management of the disease remains suboptimal. The use of phytoceuticals (plant-derived pleiotropic multitarget molecules) represents a new research trend in pancreatology. The purpose of this review is to discuss the phytoceuticals with pancreatoprotective potential in acute pancreatitis and whose efficacy is based, at least in part, on their capacity to modulate the acinar cell death. The phytochemicals selected, belonging to such diverse classes as polyphenols, flavonoids, lignans, anthraquinones, sesquiterpene lactones, nitriles, and alkaloids, target the balance between apoptosis and necrosis. Activation of apoptosis via various mechanisms (e.g., inhibition of X-linked inhibitor of apoptosis proteins by embelin, upregulation of FasL gene expression by resveratrol) and/or inhibition of necrosis seem to represent the essential key for decreasing the severity of the disease. Apart from targeting the apoptosis/necrosis balance, the phytochemicals displayed other specific protective activities: inhibition of inflammasome (e.g., rutin), suppression of neutrophil infiltration (e.g., ligustrazine, resveratrol), and antioxidant activity. Even though many of the selected phytoceuticals represent a promising therapeutic alternative, there is a shortage of human evidence, and further studies are required to provide solid basis to justify their use in the treatment of pancreatitis.

Pretreatment of a matrix metalloproteases inhibitor and aprotinin attenuated the development of acute pancreatitis-induced lung injury in rat model

OBJECTIVE

Acute lung injury (ALI) is one of the most common extra-pancreatic complications of acute pancreatitis. In this study, we examined the protective effect of protease inhibitor aprotinin and a matrix metalloproteinase inhibitor (MMPi) on pulmonary inflammation in rats with severe pancreatitis-associated ALI.

METHOD

A rat model of acute pancreatitis (AP) was established by injecting sodium glycodeoxycholate (GDOC) into the pancreatic duct. Pharmacological interventions included pretreatment with a protease inhibitor aprotinin (10mg/kg) and a matrix metalloproteinase inhibitor (MMPi, 100g/kg). The extent of pancreatic and lung injury and systemic inflammation was assessed by examinations of blood, bronchoalveolar lavage (BAL), and lung tissue. Pancreatic or lung tissue edema was evaluated by tissue water content. Pulmonary arterial pressure and alveolar-capillary membrane permeability were evaluated post-injury via a catheter inserted into the pulmonary artery in an isolated, perfused lung model.

RESULTS

Pre-treatment with aprotinin or MMPi significantly decreased amylase and lactate dehydrogenase (LDH), and the wet/dry weight ratio of the lung and pancreas in AP rats. Compared to the GDOC alone group, administration of aprotinin or MMPi prevented pancreatitis-induced IL-6 increases in the lung. Similarly, treatment with aprotinin or MMPi significantly decreased the accumulation of white blood cells, oxygen radicals, nitrite/nitrates in both blood and BAL, and markedly reduced lung permeability.

CONCLUSION

Pretreatment with either aprotinin or MMPi attenuated the systemic inflammation and reduced the severity of lung and pancreas injuries. In short, our study demonstrated that inhibition of protease may be therapeutic to pulmonary inflammation in this GDOC-induced AP model.

Activin in acute pancreatitis: Potential risk-stratifying marker and novel therapeutic target

Acute Pancreatitis is a substantial health care challenge with increasing incidence. Patients who develop severe disease have considerable mortality. Currently, no reliable predictive marker to identify patients at risk for severe disease exists. Treatment is limited to rehydration and supporting care suggesting an urgent need to develop novel approaches to improve standard care. Activin is a critical modulator of inflammatory responses, but has not been assessed in pancreatitis. Here, we demonstrate that serum activin is elevated and strongly correlates with disease severity in two established murine models of acute pancreatitis induced by either cerulein or IL-12 + IL-18. Furthermore, in mice, inhibition of activin conveys survival benefits in pancreatitis. In addition, serum activin levels were measured from a retrospective clinical cohort of pancreatitis patients and high activin levels in patients at admission are predictive of worse outcomes, indicated by longer overall hospital and intensive care unit stays. Taken together, activin is a novel candidate as a clinical marker to identify those acute pancreatitis patients with severe disease who would benefit from aggressive treatment and activin may be a therapeutic target in severe acute pancreatitis.

Intravenous hMSCs Ameliorate Acute Pancreatitis in Mice via Secretion of Tumor Necrosis Factor-α Stimulated Gene/Protein 6

The administration of mesenchymal stem cells/multipotent mesenchymal stromal cells (MSCs) to enhance tissue repair is currently undergoing clinical trials. Some studies, including our previous work, have also revealed the beneficial effect of MSCs in severe acute pancreatitis (SAP); however, their mechanisms or mode of action remain controversial. In this study, we demonstrated that intravenously (i.v.)-administered human MSCs (hMSCs) remarkably promoted recovery from experimental SAP without significant engraftment of hMSCs in the damaged pancreas. Interestingly, we found that i.v.-administered hMSCs with knockdown of TSG-6 expression lost most of their anti-inflammatory effects and thus could not significantly ameliorate SAP. As expected, the effects of hMSCs were also duplicated by i.v. infusion of recombinant TSG-6. Furthermore, our results showed that the increase of oxidative stress, activation of the NLRP3 inflammasome and NF-κB signaling in SAP was substantially inhibited following administration of hMSCs or TSG-6, which was dependent on the presence of CD-44 receptors in acinar cells. In conclusion, our study, for the first time, revealed that novel mechanisms are responsible for the immunomodulatory effect of i.v. hMSCs.

Prophylactic Administration of Silybin Ameliorates L-Arginine-Induced Acute Pancreatitis

Background

Oxidative stress have been shown to play a role in the pathogenesis of acute pancreatitis. The aim of this study was to investigate the potential effect of silybin, a potent antioxidant, on L-arginine-induced acute pancreatitis in an experimental rat model.

Material/Methods

Forty female Wistar Albino rats were divided into 5 groups as follows: Group 1 (C): control group (n=8), Group 2 (SL): silybin group (n=8), Group 3 (LA): acute pancreatitis group (n=8), Group 4 (SLLA): prophylaxis group (n=8), and Group 5 (LASL): treatment group (n=8). Group C (control) received 2 intraperitoneal (i.p.) injections of physiological saline at an interval of 1 h. Group SL received only a single i.p. injection of silybin. The SLLA group received a single i.p. injection of silybin before the induction of acute pancreatitis with L-arginine, whereas the LASL group received the same injection after the induction of acute pancreatitis with L-arginine. Pancreatic tissues were histopathologically examined. Levels of amylase and oxidative stress markers (total oxidant status and total anti-oxidant status) were determined in the blood samples. Oxidative stress index was calculated.

Results

In comparison to the LA, the prophylaxis and treatment groups showed significant improvements in serum oxidative stress parameters (p=0.001 and p=0.005, respectively). Histopathological analysis showed that the treatment group had significant improvements in edema scores only (p=0.006), whereas the prophylaxis group had the same improvements in inflammation and necrosis scores as well as in total scores (p=0.004, 0.006, and 0.004, respectively).

Conclusions

When used for prophylactic rather than therapeutic purposes, silybin ameliorates serum oxidative stress parameters and improves histopathological results via its antioxidant and anti-inflammatory properties.

Animal models of gastrointestinal and liver diseases. Animal models of acute and chronic pancreatitis

Animal models of pancreatitis are useful for elucidating the pathogenesis of pancreatitis and developing and testing novel interventions. In this review, we aim to summarize the most commonly used animal models, overview their pathophysiology, and discuss their strengths and limitations. We will also briefly describe common animal study procedures and refer readers to more detailed protocols in the literature. Although animal models include pigs, dogs, opossums, and other animals, we will mainly focus on rodent models because of their popularity. Autoimmune pancreatitis and genetically engineered animal models will be reviewed elsewhere.

Analysis of Treatment-Related Factors Affecting Mortality in Patients with Severe Necrotizing Acute Pancreatitis

The aim of the paper was to determine the factors related to the initial therapy that may contribute to death from severe necrotizing acute pancreatitis and to analyze their clinical importance as well as possible additive effects.

A retrospective case-control study included all adult patients treated for severe necrotizing acute pancreatitis in the Clinical Center of Kragujevac, Serbia, during the five-year period (2006-2010.). The cases (n = 41) were patients who died, while the controls (n = 69) were participants who survived. In order to estimate the relationship between potential risk factors and observed outcome, crude and adjusted odds ratios (OR) with 95 % confidence intervals (CI) were calculated in logistic regression models.

Significant association with observed outcome was shown for the use of gelatin and/or hydroxyethyl starch (adjusted OR 12.555; 95 % CI 1.150-137.005), use of albumin (adjusted OR 27.973; 95 % CI 1.741-449.373), use of octreotide (adjusted OR 16.069; 95 % CI 1.072-240.821) and avoiding of enteral feeding (adjusted OR 3.933; 95 % CI 1.118-13.829), while the use of nonsteroidal anti-inflammatory drugs had protective role (adjusted OR 0.057; 95 % CI 0.004-0.805).

The risk of death in patients with predicted severe necrotizing acute pancreatitis could be reduced with avoidance of treatment with colloid solutions, albumin and octreotide, as well as with an early introduction of oral/enteral nutrition and use of nonsteroidal anti-inflammatory drugs.

Tin Tungstate Nanoparticles: A Photosensitizer for Photodynamic Tumor Therapy

The nanoparticulate inorganic photosensitizer β-SnWO4 is suggested for photodynamic therapy (PDT) of near-surface tumors via reiterated 5 min blue-light LED illumination. β-SnWO4 nanoparticles are obtained via water-based synthesis and comprise excellent colloidal stability under physiological conditions and high biocompatibility at low material complexity. Antitumor and antimetastatic effects were investigated with a spontaneously metastasizing (4T1 cells) orthotopic breast cancer BALB/c mouse model. Besides protamine-functionalized β-SnWO4 (23 mg/kg of body weight, in PBS buffer), chemotherapeutic doxorubicin was used as positive control (2.5 mg/kg of body weight, in PBS buffer) and physiological saline (DPBS) as a negative control. After 21 days, treatment with β-SnWO4 resulted in a clearly inhibited growth of the primary tumor (all tumor volumes below 3 cm(3)) as compared to the doxorubicin and DPBS control groups (volumes up to 6 cm(3)). Histological evaluations of lymph nodes and lungs as well as the volume of ipsilateral lymph nodes show a remarkable antimetastatic effect being similar to chemotherapeutic doxorubicin but-according to blood counts-at significantly reduced side effects. On the basis of low material complexity, high cytotoxicity under blue-light LED illumination at low dark and long-term toxicity, β-SnWO4 can be an interesting addition to PDT and the treatment of near-surface tumors, including skin cancer, esophageal/gastric/colon tumors as well as certain types of breast cancer.

Nonproliferative and Proliferative Lesions of the Gastrointestinal Tract, Pancreas and Salivary Glands of the Rat and Mouse

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) project is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature and diagnostic criteria for nonproliferative and proliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature and diagnostic criteria for classifying lesions in the digestive system including the salivary glands and the exocrine pancreas of laboratory rats and mice. Most lesions are illustrated by color photomicrographs. The standardized nomenclature, the diagnostic criteria, and the photomicrographs are also available electronically on the Internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and age related lesions as well as lesions induced by exposure to test items. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature and diagnostic criteria for the digestive system will decrease misunderstandings among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.

A new experimental rat model of pancreatitis using Ecballium elaterium

BACKGROUND

We originally aimed to determine the beneficial effects of Ecballium Elaterium (EE) on acute pancreatitis; however, we observed negative effects of EE on the pancreas. Thus, we used EE in rats to generate a new model of pancreatitis, which we compared with other established pancreatitis models.

METHODS

A total of 32 Wistar albino rats were used. Rats were divided into 4 groups, each of which contained 8 rats. Group 1 (Control), Group 2 (L-Arginine (LA), Group 3 (LA + EE), Group 4 (EE): Twenty-four hours after that serum parameters were analyzed in the collected blood. Blood samples were transported on mice to the Biochemistry Laboratory following cardiac puncture. The levels of amylase, interleukin (IL)-6, interleukin (IL) 1-β (IL-1β), malondialdhyde (MDA), tumor necrosis factor (TNF)-α, total antioxidant status (TAS), and total oxidant status (TOS) were analyzed. Histopathological analysis: The pancreas and lung tissue samples obtained from the rats. Edema, inflammation, vacuolization, and necrosis of the pancreas were assessed using a scoring system ranging from 0 to 4. Edema, hemorrhage and inflammation of the lung tissue were evaluated using a scoring system ranging from 0 to 3.

RESULTS

Histopathological analysis revealed that edema, inflammation, necrosis, and hemorrhage were significantly higher in the LA + EE group than in the control group. Moreover, necrosis was higher in the rats that received LA and EE compared to the rats that received only LA or EE. Increases in inflammatory mediator levels, including IL-6, IL-1β, TNF-α, MDA, and TOS, were observed in all groups as compared to the control group. Moreover, lower TAS levels were detected in all groups but the control group. The increase in IL-1β and TNF-α levels and the decrease in TAS were statistically significant in all groups (P < 0.05).

CONCLUSIONS

EE may be used to create a successful acute pancreatitis (AP) model, resulting in edema, necrosis, hemorrhage, and inflammation of the pancreas. The major advantage of this model is that it does not require laparotomy, and can be implemented with only an intraperitoneal injection (IP). Moreover, EE may be combined with other agents, such as LA, to create severe pancreatitis. Further molecular studies are warranted to determine the underlying effects of EE on the pancreas.

Dual pancreas- and lung-targeting therapy for local and systemic complications of acute pancreatitis mediated by a phenolic propanediamine moiety

To inhibit both the local and systemic complications with acute pancreatitis, an effective therapy requires a drug delivery system that can efficiently overcome the blood-pancreas barrier while achieving lung-specific accumulation. Here, we report the first dual pancreas- and lung-targeting therapeutic strategy mediated by a phenolic propanediamine moiety for the treatment of acute pancreatitis. Using the proposed dual-targeting ligand, an anti-inflammatory compound Rhein has been tailored to preferentially accumulate in the pancreas and lungs with rapid distribution kinetics, excellent tissue-penetrating properties and minimum toxicity. Accordingly, the drug-ligand conjugate remarkably downregulated the proinflammatory cytokines in the target organs thus effectively inhibiting local pancreatic and systemic inflammation in rats. The dual-specific targeting therapeutic strategy may help pave the way for targeted drug delivery to treat complicated inflammatory diseases.

Immune cells and immune-based therapy in pancreatitis

Alcohol and gallstones are the most common etiologic factors in acute pancreatitis (AP). Recurrent AP can lead to chronic pancreatitis (CP). Although the underlying pathophysiology of the disease is complex, immune cells are critical in the pathogenesis of pancreatitis and determining disease severity. In this review, we discuss the role of innate and adaptive immune cells in both AP and CP, potential immune-based therapeutic targets, and animal models used to understand our knowledge of the disease. The relative difficulty of obtaining human pancreatic tissue during pancreatitis makes animal models necessary. Animal models of pancreatitis have been generated to understand disease pathogenesis, test therapeutic interventions, and investigate immune responses. Although current animal models do not recapitulate all aspects of human disease, until better models can be developed available models are useful in addressing key research questions. Differences between experimental and clinical pancreatitis need consideration, and when therapies are tested, models with established disease ought to be included.

Diagnostic value of surfactant protein-a in severe acute pancreatitis-induced acute respiratory distress syndrome

Background

The complexity of multiple-item criteria in acute respiratory distress syndrome (ARDS) often causes inconvenience for physicians in the management of patients with severe acute pancreatitis (SAP). We evaluated whether serum SP-A levels in the presence of diffuse alveolar damage (DAD) can be qualitatively assessed for diagnosis of SAP-induced ARDS.

Material/Methods

Eighty rats were randomly divided into 2 groups (n=40 each) – the sham-operated (SO) group and the SAP group – and then randomly subdivided into 4 subgroups in a time-course manner. Furthermore, rats in the SAP group were subdivided into the SAP induced-ARDS group (ARDS group) and the SAP without ARDS group (non-ARDS group) according to the diagnostic standard of ARDS. The diagnostic cut-off values of SP-A for SAP-induced ARDS were determined by the receiver operating characteristic curve (ROC).

Results

Serum SP-A levels in Baseline, SO group, SAP group, ARDS group, and non-ARDS group were 43.15±14.29, 51.91±16.99, 193.4±35.37, 198.0+29.73, and 185.7±43.21 ug/ml, respectively. The best cut-off value for the serum SP-A level for the diagnosis of SAP-induced ARDS was 150 ug/ml and the area under the ROC curve of SP-A was 0.88. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SP-A in the diagnosis of SAP-induced ARDS were 100.0%, 81.8%, 71.4%, 100.0%, and 87.5%, respectively.

Conclusions

Serum SP-A levels may allow the detection of SAP-induced ARDS and may help to support the clinical diagnosis of ARDS. The optimal serum SP-A cut-off value to discriminate SAP-induced ARDS and other groups (SO group and non-ARDS group) is around 150 ug/ml.

Therapeutic effect of human clonal bone marrow-derived mesenchymal stem cells in severe acute pancreatitis

Severe acute pancreatitis (SAP), a common necroinflammatory disease initiated by the premature activation of digestive enzymes within the pancreatic acinar cells, is associated with significant morbidity and mortality. In this study, we investigated whether human bone marrow-derived clonal mesenchymal stem cells (hcMSCs), isolated from human bone marrow aspirate according to our newly established isolation protocol, have potential therapeutic effects in SAP. SAP was induced by three intraperitoneal (i.p.) injections of cerulein (100 μg/kg) and sequential LPS (10 mg/kg) in Sprague-Dawley (SD) rats. hcMSCs (1 × 10(6)/head) were infused on 24 h after LPS injection via the tail vein. The rats were sacrificed 3 days after infusion of hcMSCs. We observed that infused hcMSCs reduced the levels of serum amylase and lipase. Infused hcMSCs ameliorated acinar cell necrosis, pancreatic edema, and inflammatory infiltration. Also, infused hcMSCs decreased the level of malondialdehyde, and increased the levels of glutathione peroxidase and superoxide dismutase. The number of TUNEL positive acinar cells was reduced after hcMSCs infusion. In addition, hcMSCs reduced the expression levels of pro-inflammation mediators and cytokines, and increased the expression of SOX9 in SAP. Taken together, hcMSCs could effectively relieve injury of pancreatitis as a promising therapeutics for SAP.

Perfluorooctanoic acid exposure triggers oxidative stress in the mouse pancreas

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PFOA triggers focal ductal hyperplasia following 7 day exposure.

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PFOA exposure increases 8-iso-PGF_2α levels in the pancreas.

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Antioxidant gene expression is upregulated in the pancreas following PFOA exposure.

Perfluorooctanoic acid (PFOA) is used in the manufacture of many industrial and commercial products. PFOA does not readily decompose in the environment, and is biologically persistent. Human epidemiologic and animal studies suggest that PFOA exposure elicits adverse effects on the pancreas. While multiple animal studies have examined PFOA-mediated toxicity in the liver, little is known about the potential adverse effects of PFOA on the pancreas. To address this, we treated C57Bl/6 mice with vehicle, or PFOA at doses of 0.5, 2.5 or 5.0 mg/kg BW/day for 7 days. Significant accumulation of PFOA was found in the serum, liver and pancreas of PFOA-treated animals. Histopathologic examination of the pancreas revealed focal ductal hyperplasia in mice treated with 2.5 and 5.0 mg/kg BW/day PFOA, while inflammation was observed only in the high dose group. Elevated serum levels of amylase and lipase were observed in the 2.5 mg/kg BW/day PFOA treatment group. In addition, PFOA exposure resulted in a dose-dependent increase in the level of the lipid peroxidation product 8-iso-PGF_2α and induction of the antioxidant response genes Sod1, Sod2, Gpx2 and Nqo1. Our findings provide additional evidence that the pancreas is a target organ for PFOA-mediated toxicity and suggest that oxidative stress may be a mechanism through which PFOA induces histopathological changes in the pancreas.

Evaluation of miR-216a and miR-217 as potential biomarkers of acute pancreatic injury in rats and mice

Mild injury of the exocrine pancreas is often asymptomatic and can be under- or mis-diagnosed. The pancreas-enriched microRNAs miR-216a and miR-217 were evaluated as potential serum biomarkers of exocrine pancreas injury in rodent models of acute pancreatitis induced by caerulein, l-arginine, and pancreatic duct ligation. Both microRNAs showed time- and dose- relevant responses to pancreatic injury and wider dynamic ranges of response than serum amylase or lipase. Pancreas-selective microRNAs were found to be relatively sensitive serum biomarkers of pancreatic injury in rodents with potentially greater specificity than the current standard assays.

Autophagy in alcohol-induced multiorgan injury: mechanisms and potential therapeutic targets

Autophagy is a genetically programmed, evolutionarily conserved intracellular degradation pathway involved in the trafficking of long-lived proteins and cellular organelles to the lysosome for degradation to maintain cellular homeostasis. Alcohol consumption leads to injury in various tissues and organs including liver, pancreas, heart, brain, and muscle. Emerging evidence suggests that autophagy is involved in alcohol-induced tissue injury. Autophagy serves as a cellular protective mechanism against alcohol-induced tissue injury in most tissues but could be detrimental in heart and muscle. This review summarizes current knowledge about the role of autophagy in alcohol-induced injury in different tissues/organs and its potential molecular mechanisms as well as possible therapeutic targets based on modulation of autophagy.

Pathomorphological analysis of the pancreaticoduodenal organs in experimental pancreonecrosis induced by trypsin injection

Acute experimental pancreatitis induced by injection of trypsin into the pancreatic tissue exhibited characteristics of fulminant hemorrhagic pancreonecrosis (intense exudation of interlobular stroma, massive plasmo- and hemorrhages, foci of acinar cell autolysis involving by the end of day 1 an appreciable portion of the organ with formation of fields of necrosis and hemorrhagic imbibition of the glandular parenchyma, virtually completely without demarcation cellular reaction). Marked microcirculatory disorders and degenerative and necrobiotic changes in the duodenal mucosa and liver reflected the polyorgan nature of the pathological process. This model of hemorrhagic pancreonecrosis corresponded to the most severe forms of this conditions observed clinically.

Duration of injury correlates with necrosis in caerulein-induced experimental acute pancreatitis: implications for pathophysiology

Pancreatic acinar cell necrosis is indicative of severe pancreatitis and the degree of necrosis is an index of its outcome. We studied whether the dose and duration of injury correlates with severity, particularly in terms of necrosis, in caerulein-induced acute pancreatitis (AP) in Swiss albino mice. In addition to control group 1 (G1), groups 2 and 3 received four injections of caerulein every hour but were sacrificed at five hours (G2) and nine hours (G3) respectively, and group 4 received eight injections and was sacrificed at nine hours (G4). The severity of pancreatitis was assessed histopathologically and biochemically. The histopathological scores of pancreatitis in groups 3 and 4 were significantly higher than in groups 1 and 2 (4 vs. 1, 4 vs. 2, 3 vs. 1, 3 vs. 2; P < 0.05). TUNEL-positive apoptotic cells were significantly higher in groups 2 and 3 compared with groups 1 and 4 (P < 0.05). Necrosis was significantly more in group 4 than other groups (37.49% (4.68) vs. 19.97% (1.60) in G2; 20.36% (1.56) in G3; P = 0.006 for G 2 vs. 4 and P = 0.019 for G 3 vs. 4). Electron microscopy revealed numerous autophagosomes in groups 2 and 3 and mitochondrial damage and necrosis in group 4. The pancreatic and pulmonary myeloperoxidase activity in group 4 was significantly higher than that in the other groups (P < 0.01). Hence, severity of pancreatitis is a function of the dose of injurious agent, while inflammation is both dose and duration dependent, which may also explain the wide spectrum of severity of AP seen in clinical practice.

Expression of human cationic trypsinogen (PRSS1) in murine acinar cells promotes pancreatitis and apoptotic cell death

Hereditary pancreatitis (HP) is an autosomal dominant disease that displays the features of both acute and chronic pancreatitis. Mutations in human cationic trypsinogen (PRSS1) are associated with HP and have provided some insight into the pathogenesis of pancreatitis, but mechanisms responsible for the initiation of pancreatitis have not been elucidated and the role of apoptosis and necrosis has been much debated. However, it has been generally accepted that trypsinogen, prematurely activated within the pancreatic acinar cell, has a major role in the initiation process. Functional studies of HP have been limited by the absence of an experimental system that authentically mimics disease development. We therefore developed a novel transgenic murine model system using wild-type (WT) human PRSS1 or two HP-associated mutants (R122H and N29I) to determine whether expression of human cationic trypsinogen in murine acinar cells promotes pancreatitis. The rat elastase promoter was used to target transgene expression to pancreatic acinar cells in three transgenic strains that were generated: Tg(Ela-PRSS1)NV, Tg(Ela-PRSS1*R122H)NV and Tg(Ela-PRSS1*N29I)NV. Mice were analysed histologically, immunohistochemically and biochemically. We found that transgene expression is restricted to pancreatic acinar cells and transgenic PRSS1 proteins are targeted to the pancreatic secretory pathway. Animals from all transgenic strains developed pancreatitis characterised by acinar cell vacuolisation, inflammatory infiltrates and fibrosis. Transgenic animals also developed more severe pancreatitis upon treatment with low-dose cerulein than controls, displaying significantly higher scores for oedema, inflammation and overall histopathology. Expression of PRSS1, WT or mutant, in acinar cells increased apoptosis in pancreatic tissues and isolated acinar cells. Moreover, studies of isolated acinar cells demonstrated that transgene expression promotes apoptosis rather than necrosis. We therefore conclude that expression of WT or mutant human PRSS1 in murine acinar cells induces apoptosis and is sufficient to promote spontaneous pancreatitis, which is enhanced in response to cellular insult.

Qualitative and quantitative contrast-enhanced ultrasonographic assessment of cerulein-induced acute pancreatitis in dogs

Background

Acute pancreatitis (AP) is the most common disease of the canine exocrine pancreas, and accurate noninvasive diagnosis is challenging.

Hypothesis/Objectives

To determine the feasibility of using quantitative contrast‐enhanced ultrasonography (CEUS) to detect pancreatic perfusional changes in cerulein‐induced AP in dogs.

Animals

Six adult female Beagles.

Methods

Each dog received 2 hours of IV infusion with 7.5 μg/kg/h of cerulein diluted in saline. As control, all dogs received 2 hours of IV infusion of saline 2 weeks before cerulein infusion. CEUS of the pancreas and duodenum were performed before (0 hour), and at 2, 4, 6, and 12 hours after saline and cerulein infusion. Time‐intensity curves were created from regions of interest in the pancreas and duodenum. Five perfusional parameters were measured for statistical analysis: time to initial up‐slope, peak time, time to wash‐out, peak intensity (PI), and area under the curve (AUC).

Results

In cerulein‐induced AP, pancreatic PI increased at 2 and 4 hours when compared to 0 hour, and at 2, 4, and 6 hours when compared to control. AUC increased at 4 hours when compared to 0 hour, and at 2 and 4 hours when compared to control. Time to wash‐out was prolonged at 4 hours when compared to control. For saline control, peak time was faster at 2 hours when compared to 0 hour.

Conclusions and Clinical Importance

CEUS parameters PI and AUC can provide useful information in differentiating acute pancreatitis from normal pancreas. Cerulein‐induced AP was characterized by prolonged hyperechoic enhancement on CEUS.

Rutin rich Emblica officinalis Geart. fruit extract ameliorates inflammation in the pancreas of rats subjected to alcohol and cerulein administration

BACKGROUND

The modulating effect of methanolic extract of Emblica officinalis (MEEO) on ethanol (EtOH)- and cerulein (Cer)-induced pancreatitis in rats was investigated in this study.

METHODS

Male albino Wistar rats were divided into four groups. Group 1 and 2 rats served as control and fed normal diet. Group 3 and 4 rats were fed isocalorically adjusted diet containing EtOH (36% of total calories) for 5 weeks and also subjected to intraperitoneal injection of Cer 20 µg/kg b.wt. thrice weekly for the last 3 weeks of the experimental period. In addition, group 2 and 4 rats received 200 mg/kg b.wt. of MEEO from 15th day till the experimental period. Serum levels of lipase (L), amylase (A), cytokines IL-1β, IL-18, caspase-1 and oxidative stress index (OSI) were determined. Levels of fecal trypsin, total collagen, caspase-1, myeloperoxidase (MPO), antioxidants and mRNA expression of caspase-1, IL-1β and IL-18 were determined in the pancreas.

RESULTS

HPLC analysis showed the presence of rutin in MEEO. We observed a significant elevation in serum L/A ratio, IL-1β, IL-18, caspase-1, OSI, collagen, MPO activity and the mRNA expression of IL-1β, IL-18 and caspase-1 and significant reduction in fecal trypsin and antioxidant status in EtOH- and Cer-administered rats. The inflammatory markers were found to be reduced and the antioxidant status of pancreas was maintained in MEEO-coadministered rats.

CONCLUSIONS

The rutin rich nature of E. officinalis can be claimed for its anti-inflammatory and pancreato protective effects.

Protective effects of fucoidan, a P- and L-selectin inhibitor, in murine acute pancreatitis

OBJECTIVE

The objective of this study was to investigate the potential protective effects of fucoidan, an L- and P-selectin modulator, in 2 murine models of acute pancreatitis.

METHODS

Acute pancreatitis was induced in mice either by the retrograde infusion of taurolithocholic acid sulfate into the pancreatic duct or by intraperitoneal injections of cerulein (50 μg/kg per hour). The experimental groups received fucoidan (25 mg/kg, intravenously) before pancreatitis induction, whereas control groups received only saline. After 24 hours, serum amylase, lipase, interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), and nitrite were measured. In addition, myeloperoxidase (MPO) activity (lung and pancreas) and histological assessment (pancreas) were determined.

RESULTS

Serum amylase, lipase, nitrite, TNF-α, and IL-1β, and pancreatic and lung MPO were increased in both taurolithocholic acid sulfate and cerulein acute pancreatitis compared with the respective control groups. Fucoidan significantly decreased the augmented levels of amylase, lipase, pancreatic and lung MPO, TNF-α, IL-1β, and nitrite in both models. Pancreas histological changes observed in both acute pancreatitis models were significantly attenuated by fucoidan.

CONCLUSIONS

Fucoidan reduced the severity of acute pancreatitis in mice by decreasing neutrophil infiltration and systemic inflammation, suggesting that modulation of selectins may constitute a promising therapeutic approach.

Animal models of pancreatitis: Can it be translated to human pain study?

Chronic pancreatitis affects many individuals around the world, and the study of the underlying mechanisms leading to better treatment possibilities are important tasks. Therefore, animal models are needed to illustrate the basic study of pancreatitis. Recently, animal models of acute and chronic pancreatitis have been thoroughly reviewed, but few reviews address the important aspect on the translation of animal studies to human studies. It is well known that pancreatitis is associated with epigastric pain, but the understanding regarding to mechanisms and appropriate treatment of this pain is still unclear. Using animal models to study pancreatitis associated visceral pain is difficult, however, these types of models are a unique way to reveal the mechanisms behind pancreatitis associated visceral pain. In this review, the animal models of acute, chronic and un-common pancreatitis are briefly outlined and animal models related to pancreatitis associated visceral pain are also addressed.