Elevation of serum interleukin-6 concentration precedes acute-phase response and reflects severity in acute pancreatitis

Circulating Markers of Necroptosis in Acute Pancreatitis

OBJECTIVES

Necroptosis, a programmed inflammatory cell death, is involved in the pathogenesis of acute pancreatitis (AP). We compared levels of interleukin (IL)-33 (released upon necroptosis), sST2 (soluble IL-33 receptor), MLKL, RIPK1 and RIPK3 (necroptosis executioner proteins), and proinflammatory cytokines IL-6, TNF and IL-1β at various severity categories and stages of AP.

METHODS

Plasma from 20 patients with early mild AP (MAP) (symptom onset < 72 h), 7 with severe AP (SAP) without and 4 with persistent organ failure (OF) at sampling, 8 patients with late SAP and 20 healthy controls (HC) were studied by ELISAs.

RESULTS

Early sST2 and IL-6 levels predicted the development of SAP and were higher in both MAP and early and late SAP than in HC. RIPK3 levels were higher than in HC in the patients who had or would later have SAP. MLKL levels were associated with the presence of OFs, particularly in the late phase, but were also higher in MAP than in HC.

CONCLUSIONS

sST2, RIPK3 and IL-6 levels may have prognostic value in AP. Elevated MLKL levels are associated with OF in AP. Better understanding of necroptosis in AP pathophysiology is needed to evaluate whether inhibiting and targeting necroptosis is a potential therapeutic option in AP.

Role of Interleukin 6 in Acute Pancreatitis: A Possible Marker for Disease Prognosis

Acute pancreatitis (AP) is a significant cause of morbidity, even in children, and is frequently associated with systemic manifestations. There are many cytokines involved in the inflammatory response characteristic of this disease. Interleukin 6 (IL-6) is one of the most important cytokines involved in AP, beginning from cellular injury and continuing to the systemic inflammatory response and distant organ involvement. IL-6 is a multifunctional cytokine that regulates acute-phase response and inflammation. It is produced by various cells and exerts its biological role on many cells through its high-affinity complex receptor. IL-6 has been investigated as a predicting maker for severe forms of AP. Many studies have validated the use of IL-6 serum levels in the first 48 h as a reliable marker for severe evolution and multisystemic involvement. Still, it has not been used in daily practice until now. This review discusses the main binding mechanisms by which IL-6 triggers cellular response and the AP pathogenetic mechanisms in which IL-6 is involved. We then emphasize the promising role of IL-6 as a prognostic marker, which could be added as a routine marker at admission in children with AP.

Triglycerides: A Sensitizer but Not a Trigger for Hypertriglyceridemic Acute Pancreatitis

BACKGROUND

The incidence of hypertriglyceridemic acute pancreatitis (HTG-AP) is increasing. Although the guideline defines the diagnostic criteria as triglyceride (TG) greater than 11.3 mmol/L, there is actually no specific threshold. Many people with hypertriglyceridemia (HTG) or obvious chyloid blood do not develop acute pancreatitis (AP).

AIMS

To explore the role of HTG in the pathogenesis of AP.

METHODS

Thirty-six male SD rats were randomly assigned into normal control, AP, HTG, HTG-AP, low-dose fenofibrate and high-dose fenofibrate groups. Serum indices and cytokine levels in serum, and pathological changes in pancreatic tissues were observed. The expression levels of TLR4 and NF-κBp65 in pancreatic tissues were detected by immunohistochemistry and Western blot.

RESULTS

In normal rats, HTG alone did not induce AP. However, after establishing the HTG-AP model with Poloxam 407 and L-arginine, serum-free fatty acid and TG levels were positively correlated with the levels of lipase, amylase, IL-1β, IL-6, pancreatic inflammation scores, and the expressions of TLR4 and NF-κBp65 (all P < 0.001). Expressions of TLR4 and NF-κBp65 were significantly increased in the pancreatic tissues of HTG-AP rats. Fenofibrate effectively decreased TG levels in HTG-AP rats and reduced the expression of TLR4 and NF-κBp65 (all P < 0.001).

CONCLUSIONS

HTG does not directly cause AP, but rather increases the susceptibility to AP or aggravates the inflammatory response. It is more like a sensitizer of inflammation rather than an activator.

Circulating Biomarkers Involved in the Development of and Progression to Chronic Pancreatitis-A Literature Review

Chronic pancreatitis (CP) is the end-stage of continuous inflammation and fibrosis in the pancreas evolving from acute- to recurrent acute-, early, and, finally, end-stage CP. Currently, prevention is the only way to reduce disease burden. In this setting, early detection is of great importance. Due to the anatomy and risks associated with direct sampling from pancreatic tissue, most of our information on the human pancreas arises from circulating biomarkers thought to be involved in pancreatic pathophysiology or injury. The present review provides the status of circulating biomarkers involved in the development of and progression to CP.

Lactobacillus reuteri Ameliorates Lipopolysaccharide-Induced Acute Lung Injury by Modulating the Gut Microbiota in Mice

Acute lung injury (ALI) causes lung inflammation and edema as well as resulting in gut microbiota disorder. Probiotics, however, can improve the gut microbiota composition and modulate its immune response, playing an important role in ALI pathogenesis. Therefore, our study aims to investigate the effect of Lactobacillus reuteri on Lipopolysaccharide (LPS)-induced ALI in mice and to probe the mechanism of its synergistic modulatory effect on the lungs and intestines. We assessed the therapeutic effects of L. reuteri in the ALI mouse model by histopathology, alveolar lavage fluid and serum inflammatory factor analysis and explored microbiome and transcriptome alterations. L. reuteri intervention effectively attenuated lung tissue injury and significantly reduced the LPS-induced inflammatory response and macrophage and neutrophil infiltration. Additionally, L. reuteri improved the intestinal barrier function and remodeled the disordered microbiota. In conclusion, our study showed that L. reuteri attenuated the inflammatory response, ameliorated the pulmonary edema, repaired the intestinal barrier, and remodeled the gut microbiota in ALI mice. This study provides new perspectives on the clinical treatment of ALI.

Comparison of Interleukin-6, C-Reactive Protein, Procalcitonin, and the Computed Tomography Severity Index for Early Prediction of Severity of Acute Pancreatitis

Background/Aims

Acute pancreatitis (AP) is a common gastrointestinal disease associated with hospitalization. With the increase in its incidence, AP has become a greater burden on healthcare resources. Early identification of patients with mild AP can facilitate the appropriate use of resources. We aimed to investigate the ability of inflammatory markers, including interleukin-6 (IL-6), procalcitonin, and C-reactive protein (CRP), as well as various scoring systems to differentiate mild AP from more severe diseases.

Methods

We retrospectively investigated patients hospitalized with AP, for whom severity assessment and clinical course confirmation were possible. Inflammatory markers were measured at admission, and CRP levels were measured 24 hours after admission (CRP2). Predictive values were calculated using the area under the receiver operating characteristic curve (AUROC) and logistic regression model analysis.

Results

Of 103 patients with AP, 42 (40.8%) were diagnosed with mild AP according to the revised Atlanta classification. Based on the AUROC, IL-6 (0.755, p<0.001), CRP2 (0.787, p<0.001), and computed tomography severity index (CTSI) (0.851, p<0.001) were useful predictors of mild AP. With standard cutoff values, the diagnostic sensitivity, specificity, and accuracy were 83.3%, 62.3%, and 70.9% for IL-6 (<50 pg/mL), and 78.6%, 63.9%, and 69.9% for CRP2 (<50 mg/L), respectively. The AUROC of IL-6 and CRP2 were significantly higher than those of other inflammatory markers and were not significantly different from that of CTSI.

Conclusions

IL-6, CRP2, and CTSI are helpful for early differentiation of AP severity. Among inflammatory markers, IL-6 has the advantage of early prediction of mild pancreatitis at the time of admission.

Local and systemic effects of interleukin-6 (IL-6) in inflammation and cancer

Interleukin-6 (IL-6) is an inflammatory cytokine, the level of which is highly elevated in most, if not all, inflammatory states. IL-6 triggers cell type-specific responses and acts on target cells via a specific interleukin-6 receptor (IL-6R), which, together with IL-6, binds to and induces the dimerization of a second receptor subunit, gp130. IL-6 also binds to soluble IL-6R, and this complex interacts with gp130, regardless of IL-6R expression. This allows cells that do not express IL-6R and would be otherwise insensitive to IL-6 to respond to it. We have generated a constitutively active version of gp130 by forced leucine-zipper-mediated dimerization, named L-gp130. Once inserted into the Rosa26 locus of mice, L-gp130 can be activated in a cell-autonomous manner by crossing these mice with any Cre-recombinase transgenic mouse strain. Activation of gp130 in hepatocytes produced liver-specific effects such as the induction of acute-phase proteins, but it also had profound systemic effects on the immune system. Such local and systemic effects of interleukin-6 will be reviewed.

Modeling Approach to Predict the Impact of Inflammation on the Pharmacokinetics of CYP2C19 and CYP3A4 Substrates

PURPOSE

For decades, inflammation has been considered a cause of pharmacokinetic variability, mainly in relation to the inhibitory effect of pro-inflammatory cytokines on the expression level and activity of cytochrome P450 (CYP). In vitro and clinical studies have shown that two major CYPs, CYP2C19 and CYP3A4, are both impaired. The objective of the present study was to quantify the impact of the inflammatory response on the activity of both CYPs in order to predict the pharmacokinetic profile of their substrates according to systemic C-reactive protein (CRP).

METHODS

The relationships between CRP concentration and both CYPs activities were estimated and validated using clinical data first on midazolam then on voriconazole. Finally, clinical data on omeprazole were used to validate the findings. For each substrate, a physiologically based pharmacokinetics model was built using a bottom-up approach, and the relationships between CRP level and CYP activities were estimated by a top-down approach. After incorporating the respective relationships, we compared the predictions and observed drug concentrations.

RESULTS

Changes in pharmacokinetic profiles and parameters induced by inflammation seem to be captured accurately by the models.

CONCLUSIONS

These findings suggest that the pharmacokinetics of CYP2C19 and CYP3A4 substrates can be predicted depending on the CRP concentration.

Nuclear Factor Kappa B Signaling Complexes in Acute Inflammation

Significance: Nuclear factor kappa B (NF-κB) is a master regulator of the inflammatory response and represents a key regulatory node in the complex inflammatory signaling network. In addition, selective NF-κB transcriptional activity on specific target genes occurs through the control of redox-sensitive NF-κB interactions. Recent Advances: The selective NF-κB response is mediated by redox-modulated NF-κB complexes with ribosomal protein S3 (RPS3), Pirin (PIR). cAMP response element-binding (CREB)-binding protein (CBP)/p300, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), activator protein-1 (AP-1), signal transducer and activator of transcription 3 (STAT3), early growth response protein 1 (EGR-1), and SP-1. NF-κB is cooperatively coactivated with AP-1, STAT3, EGR-1, and SP-1 during the inflammatory process, whereas NF-κB complexes with CBP/p300 and PGC-1α regulate the expression of antioxidant genes. PGC-1α may act as selective repressor of phospho-p65 toward interleukin-6 (IL-6) in acute inflammation. p65 and nuclear factor erythroid 2-related factor 2 (NRF2) compete for binding to coactivator CBP/p300 playing opposite roles in the regulation of inflammatory genes. S-nitrosylation or tyrosine nitration favors the recruitment of specific NF-κB subunits to κB sites. Critical Issues: NF-κB is a redox-sensitive transcription factor that forms specific signaling complexes to regulate selectively the expression of target genes in acute inflammation. Protein-protein interactions with coregulatory proteins, other transcription factors, and chromatin-remodeling proteins provide transcriptional specificity to NF-κB. Furthermore, different NF-κB subunits may form distinct redox-sensitive homo- and heterodimers with distinct affinities for κB sites. Future Directions: Further research is required to elucidate the whole NF-κB interactome to fully characterize the complex NF-κB signaling network in redox signaling, inflammation, and cancer.

PGC-1α, Inflammation, and Oxidative Stress: An Integrative View in Metabolism

Peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α is a transcriptional coactivator described as a master regulator of mitochondrial biogenesis and function, including oxidative phosphorylation and reactive oxygen species detoxification. PGC-1α is highly expressed in tissues with high energy demands, and it is clearly associated with the pathogenesis of metabolic syndrome and its principal complications including obesity, type 2 diabetes mellitus, cardiovascular disease, and hepatic steatosis. We herein review the molecular pathways regulated by PGC-1α, which connect oxidative stress and mitochondrial metabolism with inflammatory response and metabolic syndrome. PGC-1α regulates the expression of mitochondrial antioxidant genes, including manganese superoxide dismutase, catalase, peroxiredoxin 3 and 5, uncoupling protein 2, thioredoxin 2, and thioredoxin reductase and thus prevents oxidative injury and mitochondrial dysfunction. Dysregulation of PGC-1α alters redox homeostasis in cells and exacerbates inflammatory response, which is commonly accompanied by metabolic disturbances. During inflammation, low levels of PGC-1α downregulate mitochondrial antioxidant gene expression, induce oxidative stress, and promote nuclear factor kappa B activation. In metabolic syndrome, which is characterized by a chronic low grade of inflammation, PGC-1α dysregulation modifies the metabolic properties of tissues by altering mitochondrial function and promoting reactive oxygen species accumulation. In conclusion, PGC-1α acts as an essential node connecting metabolic regulation, redox control, and inflammatory pathways, and it is an interesting therapeutic target that may have significant benefits for a number of metabolic diseases.

Serum TLR9 and NF-κB Biochemical Markers in Patients with Acute Pancreatitis on Admission

Aim

The aim of this study was to investigate the serum TLR9 and NF-κB levels in patients for the diagnosis and prognostication of AP in the emergency department.

Methods

In the current study, we looked at the TLR9 and NF-κB levels in patients for the diagnosis and prognostication of AP in the emergency department.

Results

Of the patients with acute pancreatitis, 22 (49%) were male and 23 (51%) were female. The mean age of the patient group was 62 years, with a range of 25-95 years. The control group consisted of 19 (43.1%) male and 25 (56.9%) female patients. The serum TLR9 and NF-κB levels in patients for the diagnosis and prognostication of AP in the emergency department. p < 0.001 and 8.04 ± 1.76 vs. 4.76 ± 1.13; p < 0.001 and 8.04 ± 1.76 vs. 4.76 ± 1.13; κB levels in patients for the diagnosis and prognostication of AP in the emergency department. p < 0.001 and 8.04 ± 1.76 vs. 4.76 ± 1.13; κB levels in patients for the diagnosis and prognostication of AP in the emergency department. p < 0.001 and 8.04 ± 1.76 vs. 4.76 ± 1.13.

Conclusion

We demonstrated that the TLR9 and NF-κB pathway is activated in acute pancreatitis and increases the inflammatory process. This may help to further understand the pathogenesis of disorder, diagnosis, and clinical severity. We proposed that blockage of these inflammatory pathways may play a role in the prevention of the disease progression and development of inflammatory complications.κB levels in patients for the diagnosis and prognostication of AP in the emergency department.

The role of interleukin-18 in pancreatitis and pancreatic cancer

Originally described as an interferon (IFN)-γ-inducing factor, interleukin (IL)-18 has been reported to be involved in Th1 and Th2 immune responses, as well as in activation of NK cells and macrophages. There is convincing evidence that IL-18 plays an important role in various pathologies (i.e. inflammatory diseases, cancer, chronic obstructive pulmonary disease, Crohn's disease and others). Recently, IL-18 has also been shown to execute specific effects in pancreatic diseases, including acute and chronic pancreatitis, as well as pancreatic cancer. The aim of this study was to give a profound review of recent data on the role of IL-18 and its potential as a therapeutic target in pancreatic diseases. The existing data on this topic are in part controversial and will be discussed in detail. Future studies should aim to confirm and clarify the role of IL-18 in pancreatic diseases and unravel their molecular mechanisms.

A Multicenter, International Cohort Analysis of 1435 Cases to Support Clinical Trial Design in Acute Pancreatitis

Background

C-reactive protein level (CRP) and white blood cell count (WBC) have been variably used in clinical trials on acute pancreatitis (AP). We assessed their potential role.

Methods

First, we investigated studies which have used CRP or WBC, to describe their current role in trials on AP. Second, we extracted the data of 1435 episodes of AP from our registry. CRP and WBC on admission, within 24 h from the onset of pain and their highest values were analyzed. Descriptive statistical tools as Kruskal–Wallis, Mann–Whitney U, Levene’s F tests, Receiver Operating Characteristic (ROC) curve analysis and AUC (Area Under the Curve) with 95% confidence interval (CI) were performed.

Results

Our literature review showed extreme variability of CRP used as an inclusion criterion or as a primary outcome or both in past and current trials on AP. In our cohort, CRP levels on admission poorly predicted mortality and severe cases of AP; AUC: 0.669 (CI:0.569–0.770); AUC:0.681 (CI: 0.601–0.761), respectively. CRP levels measured within 24 h from the onset of pain failed to predict mortality or severity; AUC: 0.741 (CI:0.627–0.854); AUC:0.690 (CI:0.586–0.793), respectively. The highest CRP during hospitalization had equally poor predictive accuracy for mortality and severity AUC:0.656 (CI:0.544–0.768); AUC:0.705 (CI:0.640–0.769) respectively. CRP within 24 h from the onset of pain used as an inclusion criterion markedly increased the combined event rate of mortality and severe AP (13% for CRP > 25 mg/l and 28% for CRP > 200 mg/l).

Conclusion

CRP within 24 h from the onset of pain as an inclusion criterion elevates event rates and reduces the number of patients required in trials on AP.

Protective effects of maresin 1 against inflammation in experimentally induced acute pancreatitis and related lung injury

Severe acute pancreatitis (SAP) is an inflammatory disorder that progresses with local and systemic difficulties accompanied by a relatively high mortality rate. In recent years, maresin 1 (MaR1) has been shown to be a macrophage mediator with effective proresolving and anti-inflammatory properties that prevents the occurrence of various inflammatory conditions. The purpose of this study was to investigate the role of MaR1 in SAP and related lung injury. Experimental SAP was induced in mice with a combination of cerulean and lipopolysaccharide. MaR1 was administered 30 min before the primary injection of cerulean. Biochemical markers and histological injury scores were used to evaluate the severity of acute pancreatitis. To determine the degree of inflammation, serum cytokines and myeloperoxidase activity in pancreas and lung tissues were measured. Western blot analysis detected the activation of NF-κB. After MaR1 pretreatment, the activities of amylase, lipase, TNF-α, IL-1β, and IL-6 were decreased in serum, and the myeloperoxidase activity both in pancreas and in lung tissues significantly decreased, whereas the activity of anti-inflammatory cytokine IL-10 in serum was increased. MaR1-pretreated mice reduced the activation of pancreatic NF-κB and decreased the severity of pancreatic and lung-related injuries. These results confirm that MaR1 alleviated inflammation of the pancreas and lung by inhibiting the activity of NF-κB in experimentally induced acute pancreatitis and exerted anti-inflammatory effects. These findings suggest that MaR1 could be a new and useful drug in the treatment of SAP.NEW & NOTEWORTHY These results provided us evidence to confirm that maresin 1 (MaR1) can alleviate inflammation of the pancreas and lung by inhibiting the activity of NF-κB in experimental induced acute pancreatitis and exerts certain anti-inflammatory effects. These findings suggest that MaR1 could be a new and useful drug in the treatment of severe acute pancreatitis.

Efficacy of enteral glutamine supplementation in patients with severe and predicted severe acute pancreatitis- A randomized controlled trial

BACKGROUND

In severe acute pancreatitis (AP), intravenous glutamine has been shown to reduce the rate of complications, hospital stay, and mortality. In the present randomized trial, we aimed to evaluate the effect of enteral glutamine supplementation on clinical outcomes, gut permeability, systemic inflammation, oxidative stress, and plasma glutamine levels in patients with severe and predicted severe AP.

METHODS

Patients with AP admitted within 72 h of onset of symptoms were included. The primary outcome measure was development of infected pancreatic and peri-pancreatic necrosis and in-hospital mortality. High-sensitivity C-reactive protein (HS-CRP) and interleukin-6 (IL-6) were evaluated as markers of inflammation; plasma thiobarbituric acid reactive substances (TBARS) and activities of serum superoxide dismutase and glutathione peroxidase were determined to evaluate oxidative stress; serum polyethylene glycol (PEG) was tested for intestinal permeability; subjective global assessment (SGA) was used for nutritional assessment, and an improvement in organ function was measured by the Modified Marshall score. Intention-to-treat analysis was used. A p-value of < 0.05 was considered statistically significant.

RESULTS

After power calculation, we enrolled 18 patients in the glutamine and 22 in the control arm. There was no significant improvement in the development of infected necrosis and in-hospital mortality between the groups. Improvement in Modified Marshall score was observed in a higher proportion of patients receiving glutamine (15 [83.3%] vs. 12 [54.5%]; p = 0.05). Plasma glutamine levels improved more in glutamine-treated group (432.72 ± 307.83 vs. 618.06 ± 543.29 μM/L; p = 0.004), while it was lower in controls (576.90 ± 477.97 vs. 528.20 ± 410.45 μM/L; p = 0.003). PEG level was lower after glutamine supplementation (39.91 ± 11.97 vs. 32.30 ± 7.39 ng/mL; p = 0.02). Statistically significant reduction in IL-6 concentration was observed in the glutamine group at the end of treatment (87.44 ± 7.1 vs. 63.42 ± 33.7 μM/L; p = 0.02).

CONCLUSIONS

Despite absence of improvement in infected necrosis and in-hospital mortality, enteral glutamine supplementation showed improvement in gut permeability, oxidative stress, and a trend towards improvement in organ function as depicted by improvement in the Modified Marshall score.

TRIAL REGISTRATION

NCT01503320.

Interleukin-6 is required for Neuregulin-1 induced HER2 signaling in lung epithelium

A clear understanding of the mechanisms that regulate the alveolar epithelium's barrier is critical to develop new therapeutic strategies to mitigate lung injury. The HER2/HER3 receptor tyrosine kinase complex plays a central role in maintaining the alveolar-capillary barrier. This receptor complex is activated by its ligand, neuregulin-1 (NRG-1). Interleukin-6 (IL-6) is also known to induce HER2 signaling through HER2 transphosphorylation by the IL-6 receptor (IL-6R) complex (1). Due to this interaction, we hypothesized that NRG-1 and IL-6 cooperatively interacted to activate the HER2/HER3 complex. Studies were performed in cultured pulmonary epithelial cells measuring the HER2/IL-6/IL-6R/GP130 interaction and receptor activation by western blotting and confocal microscopy, IL-6 production by ELISA, and IL-6 inhibition using specific antibodies, small molecule inhibitors and shRNA. We found that IL-6 was required for NRG-1 induced activation of HER2 in pulmonary epithelial cells. IL-6 inhibition led to a decrease in NRG-1 induced HER2 activation. The IL-6R and GP130, a subunit of the IL-6R complex, were physically associated with HER2 and were required for NRG-1 induced HER2 activation. Inhibition of GP130, the β-subunit of the IL-6 receptor decreased NRG-1 induced HER2 activation lower than control by 38% Finally, HER2 activation increased IL-6 secretion more than two-fold over resting cells (526 ± 131 vs 231 ± 39.7 pg/ml), and inhibition of HER2 gene expression decreased basal IL-6 secretion over 80% (89 + 4.6 vs 1.3 + 0.8 pg/ml). These findings identify a requirement for IL-6 and the IL-6R complex to allow NRG-1 mediated HER2 activation, and a HER2 driven IL-6 production feedback loop.

[Treatment of acute necrotizing pancreatitis]

Acute pancreatitis (AP) has an annual incidence of 30-45 per 100,000 inhabitants. In Germany approximately one third of the cases are of biliary or alcoholic origin. The diagnosis is based on the typical epigastric pain with radiation and a threefold increase of lipase or amylase in serum. Imaging procedures only rarely need to be included for the primary diagnostics. An early risk assessment is important to be able to allocate patients with severe AP to surveillance in an intensive care unit (ICU). Elevation of blood urea nitrogen, hematocrit and blood glucose are early predictors of poor outcome.The removal of impacted gall-stones by endoscopic retrograde cholangiography (ERC) is the only causal treatment of biliary AP, which must be carried out when there are signs of cholangitis and in severe biliary AP. Pain management and early fluid substitution are the most important symptomatic approaches. In the early phase of AP 150-250 ml/h of crystalloid solution should be administered to compensate for the extravasal loss of fluid. In certain cases, the initial fluid requirement might be even higher. In the ICU setting echocardiography and advanced hemodynamic monitoring are available for guidance. Prophylactic antibiotic treatment is not recommended in mild AP and it is a matter of debate even in severe AP. Early enteral nutrition has been shown to improve the outcome. Even in cases of fluid collection and necrosis a primary surgery approach should be avoided in favor of a "step-up" procedure with radiologically guided drainage as well as endoscopic and if necessary video-assisted percutaneous retroperitoneal débridement. Surgery remains an option for complications and for infected necrosis which cannot be reached by any other means.

Visnagin attenuates acute pancreatitis via Nrf2/NFκB pathway and abrogates associated multiple organ dysfunction

Acute pancreatitis (AP) is an exocrine dysfunction of the pancreas where oxidative stress and inflammatory cytokines play a key role in induction and progression of the disease. Studies have demonstrated that antioxidant phytochemicals have been effective in improving pancreatitis condition, but there are no clinically approved drugs till date. Our study aims to assess the preventive activity of visnagin, a novel phytochemical isolated from Ammi visnaga against cerulein induced AP. Male Swiss albino mice were divided into six groups (n = 6, each group) comprising of normal control, cerulein control, seven day pre-treatment with visnagin at three dose levels; visnagin low dose (10 mg/kg), visnagin mid dose (30 mg/kg), visnagin high dose (60 mg/kg) and visnagin control (60 mg/kg). AP was induced by six injections of cerulein (50 μg/kg, i.p.) on the 7^th day and the animals were sacrificed after 6 h of last cerulein dose. Various markers of pancreatic function, oxidative stress and inflammation were assessed. Visnagin was found to be effective in reducing plasma amylase and lipase levels, reduced cerulein induced oxidative stress. Visnagin dose dependently decreased the expression of IL-1β, IL-6, TNF-α and IL-17. It attenuated the levels of nuclear p65-NFκB. Visnagin improved the antioxidant defence by improving Nrf2 expression and halted pancreatic inflammation by suppressing NFκB and nitrotyrosine expression in the acinar cells. Further, it attenuated the expression of markers of multiple organ dysfunction syndrome and reduced inflammatory cytokines in lungs and intestine. Cumulatively, these findings indicate that visnagin has substantial potential to prevent cerulein induced AP.

Apigenin Decreases Acinar Cell Damage in Pancreatitis

OBJECTIVE

Chronic pancreatitis is the consequence of multiple episodes of recurrent acute pancreatitis (RAP). We hypothesized that apigenin can minimize the sequelae of RAP by limiting acinar cells' proinflammatory signaling pathways.

METHODS

AR42J acinar cells were treated in vitro with transforming growth factor β (TGF-β), apigenin, and other inhibitors. Dual luciferase reporter assay measured parathyroid hormone-related protein (PTHrP) promoter activity. MAPK/ERK pathway activity was assessed by immunoblotting and in vivo by immunohistochemistry with a cerulein-induced RAP mouse model. Nuclear factor κ B nuclear localization was analyzed in vitro in cells stimulated with tumor necrosis factor α. Primary acini were isolated and treated with cerulein; interleukin 6 messenger RNA was measured comparing PTHrP wild-type and knockout mice.

RESULTS

Apigenin and PD98059 each downregulated TGF-β stimulation of PTHrP P3 promoter activity. In a RAP mouse model, apigenin reduced pERK nuclear localization in acinar cells and preserved acinar cell architecture. Apigenin suppressed tumor necrosis factor α-mediated signaling by decreasing nuclear factor κ B nuclear localization and decreased interleukin 6 messenger RNA levels via a PTHrP-dependent mechanism.

CONCLUSIONS

Apigenin reduced inflammatory responses in experimental models of RAP. The mechanisms mediating the actions of apigenin, in part, are owing to attenuation of PTHrP and TGF-β proinflammatory signaling.

Cytokine profile in prediction of acute lung injury in patients with acute pancreatitis

OBJECTIVES

To study the role of cytokines in prediction of acute lung injury (ALI) in acute pancreatitis.

METHODS

Levels of TNFα, IL-6, IL-10, IL-8 and IL-1β were measured in 107 patients at presentation and at 72 h in patients who developed acute lung injury. A model was devised to predict development of ALI using cytokine levels and SIRS score.

RESULTS

The levels of TNF α (p < 0.0001), IL-6 (p < 0.0001), IL-8 (p < 0.0001) and IL-1β (p < 0.0001) were significantly higher in the ALI group. IL-10 levels were significantly lower in persistent ALI (p-ALI) than in transient ALI (t-ALI) patients (p < 0.038). p-ALI group had significant rise of TNFα (p = 0.019) and IL-1β (p = 0.001) while t-ALI group had significant rise of only IL-1β (p = 0.044) on day 3 vs day 1. Combined values of IL-6 and IL-8 above 251 pg/ml had sensitivity of 90.9% and a specificity of 100% to predict future development of ALI. Composite marker-I (IL6 ≥ 80 pg/ml + SIRS) yielded sensitivity and specificity of 73% and 98% whereas composite marker-II (IL8 ≥ 100 pg/ml + SIRS) yielded sensitivity and specificity of 73% and 95% to predict future ALI.

CONCLUSIONS

IL-6 and IL-8 can predict future development of ALI. When they are combined with SIRS, they can be used as comprehensive composite markers.

Biomimetic carbon monoxide delivery based on hemoglobin vesicles ameliorates acute pancreatitis in mice via the regulation of macrophage and neutrophil activity

Macrophages play a central role in various inflammatory disorders and are broadly divided into two subpopulations, M1 and M2 macrophage. In the healing process in acute inflammatory disorders, shifting the production of M1 macrophages to M2 macrophages is desirable, because M1 macrophages secrete pro-inflammatory cytokines, whilst the M2 variety secrete anti-inflammatory cytokines. Previous findings indicate that when macrophages are treated with carbon monoxide (CO), the secretion of anti-inflammatory cytokine is increased and the expression of pro-inflammatory cytokines is inhibited, indicating that CO may have a potential to modulate the production of macrophages toward the M2-like phenotype. In this study, we examined the issue of whether CO targeting macrophages using a nanotechnology-based CO donor, namely CO-bound hemoglobin vesicles (CO-HbV), modulates their polarization and show therapeutic effects against inflammatory disorders. The results showed that the CO-HbV treatment polarized a macrophage cell line toward an M2-like phenotype. Furthermore, in an in vivo study using acute pancreatitis model mice as a model of an inflammatory disease, a CO-HbV treatment also tended to polarize macrophages toward an M2-like phenotype and inhibited neutrophil infiltration in the pancreas, resulting in a significant inflammation. In addition to the suppression of acute pancreatitis, CO-HbV diminished a subsequent pancreatitis-associated acute lung injury. This could be due to the inhibition of the systemic inflammation, neutrophil infiltration in the lungs and the production of HMGB-1. These findings suggest that CO-HbV exerts superior anti-inflammatory effects against inflammatory disorders via the regulation of macrophage and neutrophil activity.

Ghrelin improves pilocarpine‑induced cerebral cortex inflammation in epileptic rats by inhibiting NF‑κB and TNF‑α

Ghrelin has a protective function in the nervous system, including anti‑inflammatory and antiapoptotic. The objective of the present study was to examine the anti‑inflammatory effects of the ghrelin on nuclear factor‑κB (NF‑κB) and tumor necrosis factor‑α (TNF‑α) gene and protein expression in an epileptic seizure model. Epileptic seizures were induced in healthy male Wistar rats (~3 weeks old) with 300 mg/kg pilocarpine, and brains from rats with Racine stage IV or V seizures were investigated further in the present study. The effect of ghrelin treatment on TNF‑α and NF‑κB protein and mRNA expression was assessed by immunohistochemistry and semi‑quantitative reverse transcription polymerase chain reaction, respectively. TNF‑α and NF‑κB protein and mRNA expression were significantly increased in the pilocarpine and the pilocarpine + saline groups compared with the control group. Ghrelin intervention significantly decreased TNF‑α and NF‑κB protein and mRNA expression compared with the pilocarpine and the pilocarpine + saline groups, although it did not reduce expression levels to those seen in the normal control group. Ghrelin reduces inflammation in cortical neurons following epileptic seizure, and therefore may reduce necrosis and the loss of nerve cells, preserving the normal function of the cortex. Ghrelin may alleviate cortex inflammation reaction by adjusting the TNF‑α and NF‑κB so as to reduce child epilepsy attack repeatedly. The findings of the present study may contribute to the clarification of the role of Ghrelin in the brain in seizure‑induced immune system physiology and may also present novel approaches to the etiology and treatment of epileptic seizures.

Penehyclidine hydrochloride preconditioning provides pulmonary and systemic protection in a rat model of lung ischaemia reperfusion injury

Penehyclidine hydrochloride (PHC) is a new anticholinergic agent that provides protective effects in experimental models of heart and brain ischaemia as well as reperfusion (I/R) injury. In this study, we tested the hypothesis that PHC can alleviate lung ischaemia-reperfusion injury and improve pulmonary and systemic function in rats. PHC was administered intravenously at various doses (d= 0.1, 0.3, 1, 3 mg/kg) to I/R rats. We used six indicators, including lung function, histologic examination, pulmonary oedema, oxidative stress, inflammatory responses, and apoptosis staining to quantify the pulmonary and systemic protective effects of PHC. Haematoxylin and eosin staining was used for pulmonary histologic examination. The expression of Toll-like receptor (TLR) 4, phospho-inhibitor of NF-κB (p-IκB) and nuclear factor-kappa B (NF-κB) was analysed using western blotting. ELISA was conducted to detect inflammatory mediators. Oxidative stress markers as well as myeloperoxidase (MPO) were determined using an assay kit. PHC preconditioning (with concentrations ranging from 0.3 mg/kg to 3 mg/kg 30 min before the onset of I/R) significantly reduced lung histopathological changes, down regulated TLR4, p-IκB and NF-κB expression, and decreased inflammatory mediators as well as the total number of leukocytes and neutrophils in bronchoalveolar lavage (BAL) fluid and plasma. The lung tissue contents of reactive oxygen species (ROS), malondialdehyde (MDA), and MPO as well as pulmonary oedema formation decreased, while SOD (superoxide dismutase) activity was significantly upregulated. PHC preconditioning (with concentrations ranging from 1 mg/kg to 3 mg/kg) significantly improved the lung function and attenuated the apoptotic rate. The probable mechanism for this finding is the inhibition of proinflammatory mediators via the suppression of reactive oxygen species production and the TLR4/NF-κB signalling pathway.

TH1 and TH2 Cytokine Profiles as Predictors of Severity in Acute Pancreatitis

OBJECTIVES

Acute pancreatitis (AP) is severe in up to 20% of patients, with a high mortality rate. Quantification of serum TH1 and TH2 cytokines may provide objective evidence to assess the severity of AP and predict its course.

METHODS

One hundred seventeen patients were studied, measuring serum concentrations of interleukin (IL)1β, IL2, IL4, IL5, IL6, IL10, IL12p70, IL13, IL18, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN) γ, and tumor necrosis factor (TNF) α.

RESULTS

Significant differences were found between patients with severe AP and those with mild or moderately severe AP in IFN-γ (P < 0.001), IL6 (P < 0.001), TNF-α (P = 0.002), GM-CSF (P < 0.001), IL4 (P = 0.002), IL1b (P = 0.017), and IL13 (P < 0.001) concentrations. Interferon-γ, IL6, and TNF-α were associated with severe AP, whereas GM-CSF, IL4, IL1b, and IL13 were associated with mild or moderately severe AP. The IL13/IFNγ ratio was significantly higher in patients with mild AP (P = 7.36 × 10).

CONCLUSIONS

A TH1 profile was associated with severe AP and a TH2 profile with mild or moderately severe AP. We report an IL13/IFNγ ratio of potential value to predict the prognosis in AP.

A Mini-Review on the Effect of Docosahexaenoic Acid (DHA) on Cerulein-Induced and Hypertriglyceridemic Acute Pancreatitis

Acute pancreatitis refers to the sudden inflammation of the pancreas. It is associated with premature activation and release of digestive enzymes into the pancreatic interstitium and systemic circulation, resulting in pancreatic tissue autodigestion and multiple organ dysfunction, as well as with increased cytokine production, ultimately leading to deleterious local and systemic effects. Although mechanisms involved in pathogenesis of acute pancreatitis have not been completely elucidated, oxidative stress is regarded as a major risk factor. In human acute pancreatitis, lipid peroxide levels in pancreatic tissues increase. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid (C22:6n-3), exerts anti-inflammatory and antioxidant effects on various cells. Previous studies have shown that DHA activates peroxisome proliferator-activated receptor-γ and induces catalase, which inhibits oxidative stress-mediated inflammatory signaling required for cytokine expression in experimental acute pancreatitis using cerulein. Cerulein, a cholecystokinin analog, induces intra-acinar activation of trypsinogen in the pancreas, which results in human acute pancreatitis-like symptoms. Therefore, DHA supplementation may be beneficial for preventing or inhibiting acute pancreatitis development. Since DHA reduces serum triglyceride levels, addition of DHA to lipid-lowering drugs like statins has been investigated to reduce hypertriglyceridemic acute pancreatitis. However, high DHA concentrations increase cytosolic Ca²⁺, which activates protein kinase C and may induce hyperlipidemic acute pancreatitis. In this review, effect of DHA on cerulein-induced and hypertriglyceridemic acute pancreatitis has been discussed. The relation of high concentration of DHA to hyperlipidemic acute pancreatitis has been included.

Docosahexaenoic Acid Inhibits Cerulein-Induced Acute Pancreatitis in Rats

Oxidative stress is an important regulator in the pathogenesis of acute pancreatitis (AP). Reactive oxygen species induce activation of inflammatory cascades, inflammatory cell recruitment, and tissue damage. NF-κB regulates inflammatory cytokine gene expression, which induces an acute, edematous form of pancreatitis. Protein kinase C δ (PKCδ) activates NF-κB as shown in a mouse model of cerulein-induced AP. Docosahexaenoic acid (DHA), an ω-3 fatty acid, exerts anti-inflammatory and antioxidant effects in various cells and tissues. This study investigated whether DHA inhibits cerulein-induced AP in rats by assessing pancreatic edema, myeloperoxidase activity, levels of lipid peroxide and IL-6, activation of NF-κB and PKCδ, and by histologic observation. AP was induced by intraperitoneal injection (i.p.) of cerulein (50 μg/kg) every hour for 7 h. DHA (13 mg/kg) was administered i.p. for three days before AP induction. Pretreatment with DHA reduced cerulein-induced activation of NF-κB, PKCδ, and IL-6 in pancreatic tissues of rats. DHA suppressed pancreatic edema and decreased the abundance of lipid peroxide, myeloperoxidase activity, and inflammatory cell infiltration into the pancreatic tissues of cerulein-stimulated rats. Therefore, DHA may help prevent the development of pancreatitis by suppressing the activation of NF-κB and PKCδ, expression of IL-6, and oxidative damage to the pancreas.

Effects of Tocilizumab on Experimental Severe Acute Pancreatitis and Associated Acute Lung Injury

OBJECTIVE

To examine the therapeutic effects of tocilizumab, an antibody against interleukin-6 receptor, on experimental severe acute pancreatitis and associated acute lung injury. The optimal dose of tocilizumab and the activation of interleukin-6 inflammatory signaling were also investigated.

DESIGN

Randomized experiment.

SETTING

Research laboratory at a university hospital.

SUBJECT

Experimental severe acute pancreatitis in rats.

INTERVENTIONS

Severe acute pancreatitis was induced by retrograde injection of sodium taurocholate (50 mg/kg) into the biliopancreatic duct. In dose-study, rats were administered with different doses of tocilizumab (1, 2, 4, 8, and 16 mg/kg) through the tail vein after severe acute pancreatitis induction. In safety-study, rats without severe acute pancreatitis induction were treated with high doses of tocilizumab (8, 16, 32, and 64 mg/kg). Serum and tissue samples of rats in time-study were collected for biomolecular and histologic evaluations at different time points (2, 6, 12, 18, and 24 hr).

MEASUREMENTS AND MAIN RESULTS

1) Under the administration of tocilizumab, histopathological scores of pancreas and lung were decreased, and severity parameters related to severe acute pancreatitis and associated lung injury, including serum amylase, C-reactive protein, lung surfactant protein level, and myeloperoxidase activity, were all significant alleviated in rat models. 2) Dose-study demonstrated that 2 mg/kg tocilizumab was the optimal treatment dose. 3) Basing on multi-organ pathologic evaluation, physiological and biochemical data, no adverse effect and toxicity of tocilizumab were observed in safety-study. 4) Pancreatic nuclear factor-κB and signal transducer and activator of transcription 3 were deactivated, and the serum chemokine (C-X-C motif) ligand 1 was down-regulated after tocilizumab administration.

CONCLUSIONS

Our study demonstrated tocilizumab, as a marketed drug commonly used for immune-mediated diseases, was safe and effective for the treatment of experimental severe acute pancreatitis and associated acute lung injury. Our findings provide experimental evidences for potential clinical application of tocilizumab in severe acute pancreatitis and associated complications.

Docosahexaenoic acid inhibits IL-6 expression via PPARγ-mediated expression of catalase in cerulein-stimulated pancreatic acinar cells

Cerulein pancreatitis mirrors human acute pancreatitis. In pancreatic acinar cells exposed to cerulein, reactive oxygen species (ROS) mediate inflammatory signaling by Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 3, and cytokine induction. Docosahexaenoic acid (DHA) acts as an agonist of peroxisome proliferator activated receptor γ (PPARγ), which mediates the expression of some antioxidant enzymes. We hypothesized that DHA may induce PPARγ-target catalase expression and reduce ROS levels, leading to the inhibition of JAK2/STAT3 activation and IL-6 expression in cerulein-stimulated acinar cells. Pancreatic acinar AR42J cells were treated with DHA in the presence or absence of the PPARγ antagonist GW9662, or treated with the PPARγ agonist troglitazone, and then stimulated with cerulein. Expression of IL-6 and catalase, ROS levels, JAK2/STAT3 activation, and nuclear translocation of PPARγ were assessed. DHA suppressed the increase in ROS, JAK2/STAT3 activation, and IL-6 expression induced nuclear translocation of PPARγ and catalase expression in cerulein-stimulated AR42J cells. Troglitazone inhibited the cerulein-induced increase in ROS and IL-6 expression, but induced catalase expression similar to DHA in AR42J cells. GW9662 abolished the inhibitory effect of DHA on cerulein-induced increase in ROS and IL-6 expression in AR42J cells. DHA-induced expression of catalase was suppressed by GW9662 in cerulein-stimulated AR42J cells. Thus, DHA induces PPARγ activation and catalase expression, which inhibits ROS-mediated activation of JAK2/STAT3 and IL-6 expression in cerulein-stimulated pancreatic acinar cells.

Deletion Of XIAP reduces the severity of acute pancreatitis via regulation of cell death and nuclear factor-κB activity

Severe acute pancreatitis (SAP) still remains a clinical challenge, not only for its high mortality but the uncontrolled inflammatory progression from acute pancreatitis (AP) to SAP. Cell death, including apoptosis and necrosis are critical pathology of AP, since the severity of pancreatitis correlates directly with necrosis and inversely with apoptosis Therefore, regulation of cell death from necrosis to apoptosis may have practicably therapeutic value. X-linked inhibitor of apoptosis protein (XIAP) is the best characterized member of the inhibitor of apoptosis proteins (IAP) family, but its function in AP remains unclear. In the present study, we investigated the potential role of XIAP in regulation of cell death and inflammation during acute pancreatitis. The in vivo pancreatitis model was induced by the administration of cerulein with or without lipopolysaccharide (LPS) or by the administration of l-arginine in wild-type or XIAP-deficient mice, and ex vivo model was induced by the administration of cerulein+LPS in AR42J cell line following XIAP inhibition. The severity of acute pancreatitis was determined by serum amylase activity and histological grading. XIAP deletion on cell apoptosis, necrosis and inflammatory response were examined. Caspases activities, nuclear factor-κB (NF-κB) activation and receptor-interacting protein kinase1 (RIP1) degradation were assessed by western blot. Deletion of XIAP resulted in the reduction of amylase activity, decrease of NF-κB activation and less release of TNF-α and IL-6, together with increased caspases activities and RIP1 degradation, leading to enhanced apoptosis and reduced necrosis in pancreatic acinar cells and ameliorated the severity of acute pancreatitis. Our results indicate that deletion of XIAP switches cell death away from necrosis to apoptosis and decreases the inflammatory response, effectively attenuating the severity of AP/SAP. The critical role of XIAP in cell death and inflammation suggests that inhibition of XIAP represents a potential therapeutic strategy for the treatment of acute pancreatitis.

Protective Effects of Emodin-Induced Neutrophil Apoptosis via the Ca2+-Caspase 12 Pathway against SIRS in Rats with Severe Acute Pancreatitis

Severe acute pancreatitis (SAP) results in high mortality. This is partly because of early multiple organ dysfunction syndromes that are usually caused by systemic inflammatory response syndrome (SIRS). Many studies have reported the beneficial effects of emodin against SAP with SIRS. However, the exact mechanism underlying the effect of emodin remains unclear. This study was designed to explore the protective effects and underlying mechanisms of emodin against SIRS in rats with SAP. In the present study, cytosolic Ca²⁺ levels, calpain 1 activity, and the expression levels of the active fragments of caspases 12 and 3 decreased in neutrophils from rats with SAP and increased after treatment with emodin. Delayed neutrophil apoptosis occurred in rats with SAP and emodin was able to reverse this delayed apoptosis and inhibit SIRS. The effect of emodin on calpain 1 activity, the expression levels of the active fragments of caspases 12 and 3, neutrophil apoptosis, and SIRS scores were attenuated by PD150606 (an inhibitor of calpain). These results suggest that emodin inhibits SIRS in rats with SAP by inducing circulating neutrophil apoptosis via the Ca²⁺-calpain 1-caspase 12-caspase 3 signaling pathway.

Role of Daphnetin in Rat Severe Acute Pancreatitis Through the Regulation of TLR4/NF-[Formula: see text]B Signaling Pathway Activation

Severe acute pancreatitis (SAP) often results in multiple-organ dysfunction syndrome with high mortality. There is no effective clinical therapy for SAP, yet daphnetin, a coumarin extracted from Dracaena marginata, has analgesic and anti-inflammatory effects, and has been used clinically in several diseases. The objective of this study was to investigate the role and underlying mechanisms of daphnetin in a rat SAP model. Male Wistar rats were pretreated with daphnetin via intraperitoneal injection, 30[Formula: see text]min before retrograde infusion of 5% sodium taurocholate into the biliopancreatic duct. Twelve hours after sodium taurocholate administration, rats were sacrificed and tissues and blood were harvested. Then, histological, chemical, and molecular analyses were performed. Daphnetin treatment reduced the levels of serum alanine transaminase and creatinine (CR), increased superoxide dismutase(SOD) activity, and decreased neutrophil infiltration and cell apoptosis of the pancreatic tissues in rat SAP. Daphnetin treatment significantly decreased expression of pro-inflammatory cytokines and increased expression of anti-inflammatory cytokines in rat SAP. Molecular analyses revealed that daphnetin reduced TLR4 expression and inhibited NF-[Formula: see text]B signaling pathway activation. These findings demonstrate that daphnetin attenuates acute pancreatic injury by regulating the TLR4/NF-[Formula: see text]B signaling pathway and inflammation in rat SAP model. Daphnetin may be a potential therapeutic agent for SAP.

Effects of Cytokines and Other Inflammatory Mediators on Human Acute Pancreatitis

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

IL-6, IL-10 and TNFα do not improve early detection of post-endoscopic retrograde cholangiopancreatography acute pancreatitis: a prospective cohort study

The most reliable indicators for post-ERCP acute pancreatitis are elevated amylase levels and abdominal pain 24 hours after ERCP. As ERCP is often performed on an outpatient basis, earlier diagnosis is important. We aimed to identify early predictors of post-ERCP pancreatitis. We prospectively analyzed IL-6, IL-10, TNFα, CRP, amylase and lipase before and 4 hours after ERCP, and studied their association with abdominal pain. We included 510 patients. Post-ERCP pancreatitis occurred in 36 patients (7.1%). IL-6, IL-10, TNFα and CRP were not associated with post-ERCP pancreatitis. Levels of amylase and lipase were higher in patients with pancreatitis (522 U/L and 1808 U/L vs. 78 U/L and 61 U/L, respectively; p < 0.001). A cut-off of 218 U/L for amylase (x2.2 ULN) and 355 U/L for lipase (x6 ULN) had a negative predictive value of 99.2% and 99.5%, respectively. Amylase and lipase present a good correlation (Pearson coefficient 0.912). Among 342 (67.1%) patients without abdominal pain at 4 hours, post-ERCP pancreatitis was diagnosed in 8 (2.3%). Only 4 of these patients presented amylase or lipase > 3 ULN. Amylase and lipase were the only markers of post-ERCP pancreatitis 4 hours after the procedure.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Resolvin D1 protects against inflammation in experimental acute pancreatitis and associated lung injury

Acute pancreatitis is an inflammatory condition that may lead to multisystemic organ failure with considerable mortality. Recently, resolvin D1 (RvD1) as an endogenous anti-inflammatory lipid mediator has been confirmed to protect against many inflammatory diseases. This study was designed to investigate the effects of RvD1 in acute pancreatitis and associated lung injury. Acute pancreatitis varying from mild to severe was induced by cerulein or cerulein combined with LPS, respectively. Mice were pretreated with RvD1 at a dose of 300 ng/mouse 30 min before the first injection of cerulein. Severity of AP was assessed by biochemical markers and histology. Serum cytokines and myeloperoxidase (MPO) levels in pancreas and lung were determined for assessing the extent of inflammatory response. NF-κB activation was determined by Western blotting. The injection of cerulein or cerulein combined with LPS resulted in local injury in the pancreas and corresponding systemic inflammatory changes with pronounced severity in the cerulein and LPS group. Pretreated RvD1 significantly reduced the degree of amylase, lipase, TNF-α, and IL-6 serum levels; the MPO activities in the pancreas and the lungs; the pancreatic NF-κB activation; and the severity of pancreatic injury and associated lung injury, especially in the severe acute pancreatitis model. These results suggest that RvD1 is capable of improving injury of pancreas and lung and exerting anti-inflammatory effects through the inhibition of NF-κB activation in experimental acute pancreatitis, with more notable protective effect in severe acute pancreatitis. These findings indicate that RvD1 may constitute a novel therapeutic strategy in the management of severe acute pancreatitis.

Protective effects of patchouli alcohol isolated from Pogostemon cablin on lipopolysaccharide-induced acute lung injury in mice

Patchouli alcohol (PA) is a tricyclic sesquiterpene isolated from Pogostemon cablin, which exerts anti-inflammatory, anti-influenza and cognitive-enhancing bioactivities. The present study aimed to investigate the protective effects of PA on acute lung injury (ALI) induced by intratracheal instillation of lipopolysaccharide (LPS) in mice. Dexamethasone was used as a positive drug for protection against LPS-induced ALI. The results of the present study demonstrated that pretreatment with PA significantly increased survival rate, attenuated histopathologic damage and lung edema, and decreased the protein content in the bronchoalveolar lavage fluid (BALF) of mice with ALI. Furthermore, PA significantly inhibited the expression levels of proinflammatory cytokines, including tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the BALF, downregulated the levels of myeloperoxidase and malondialdehyde, and upregulated the activity levels of superoxide dismutase and glutathione peroxidase in lung tissue. These results indicated that PA may exert potent protective effects against LPS-induced ALI in mice, the mechanisms of which are possibly associated with the anti-inflammatory and antioxidative activities of PA.

Metaflammatory responses during obesity: Pathomechanism and treatment

Obesity induced inflammation acts as a reflex produced due to altered metabolic homeostasis in accordance to the nutrient overload on the metabolic cells. It involves up-regulation of the genes encoding for cytokines, chemokines and other inflammatory mediators through activated transcription factors - nuclear factor-kB, activator protein-1, nuclear factor of activated T cells and signal transducer and activator of transcription 3. These execute macromolecular innate immune cell sensor - inflammasome to activate caspase-1 pathway resulting in proteolytic maturation. Secretion of pro-inflammatory cytokines including TNF-α, IL-6, CRP, IL-1β, etc. from the M1 macrophages of white adipose tissue is increased, whereas there occurs a steep decline in the production of anti-inflammatory cytokines like IL-10, IL-Ra, adiponectin. Not only the adipose tissue, but also the immune cells, liver, brain, muscles and pancreas suffers from the inflammatory insult during obese condition and are exaggeratedly affected. The inflammatory kinases like JNK and IKK apart from inhibiting insulin action and glucose uptake, down-regulate transcriptional process resulting in increased expression of pro-inflammatory cytokines. Macrophage-like Kupffer cells initiate the inflammatory process in the liver preceding the inflammatory signals produced by the white adipose tissue which may further lead to hepatic-necro-inflammation. The muscle-fibre is affected by the cytokines and therefore results in decreased glycogen synthesis. The triggered hypothalamic-pituitary-adrenal axis further affects the expression of inflammatory cytokines thus altering insulin homeostasis and initiating glucose intolerance. Anti-inflammatory treatment so as to curb the severity of inflammatory responses includes administration of synthetic drugs to target the actual inflammatory molecules and various therapeutic interventions.

Cystathionine-gamma-lyase gene silencing with siRNA in monocytes/macrophages protects mice against acute pancreatitis

Hydrogen sulphide (H2S) is an endogenous inflammatory mediator produced by cystathionine-γ-lyase (CSE) in monocytes/macrophages. To determine the role of H2S and macrophages in inflammation, we used small interference RNA (siRNA) to target the CSE gene and investigated its effect in a mouse model of acute pancreatitis. Acute pancreatitis is characterised by increased levels of plasma amylase, myeloperoxidase (MPO) activity and pro-inflammatory cytokines and chemokines in the pancreas and lung. SiRNA treatment attenuated inflammation in the pancreas and lungs of mice following caerulein-induced acute pancreatitis. MPO activity increased in caerulein-induced acute pancreatitis (16.21 ± 3.571 SD fold increase over control) and treatment with siRNA significantly reduced this (mean 3.555 ± 2.522 SD fold increase over control) (p < 0.0001). Similarly, lung MPO activity increased following treatment with caerulein (3.56 ± 0.941 SD fold increase over control) while siRNA treatment significantly reduced MPO activity (0.8243 ± 0.4353 SD fold increase over control) (p < 0.0001). Caerulein treatment increased plasma amylase activity (7094 ± 207 U/l) and this significantly decreased following siRNA administration (5895 ± 115 U/l) (p < 0.0001). Cytokine and chemokine levels in caerulein-induced acute pancreatitis reduced following treatment with siRNA. For example, siRNA treatment significantly decreased pancreatic and lung monocyte chemoattractant protein (MCP)-1 (169.8 ± 59.75 SD; 90.01 ± 46.97 SD pg/ml, respectively) compared to caerulein-treated mice (324.7 ± 103.9 SD; 222.8 ± 85.37 SD pg/ml, pancreas and lun,g respectively) (p < 0.0001). These findings show a crucial pro-inflammatory role for H2S synthesised by CSE in macrophages in acute pancreatitis and suggest CSE gene silencing with siRNA as a potential therapeutic approach for this condition.

Redox signaling in acute pancreatitis

Acute pancreatitis is an inflammatory process of the pancreatic gland that eventually may lead to a severe systemic inflammatory response. A key event in pancreatic damage is the intracellular activation of NF-κB and zymogens, involving also calcium, cathepsins, pH disorders, autophagy, and cell death, particularly necrosis. This review focuses on the new role of redox signaling in acute pancreatitis. Oxidative stress and redox status are involved in the onset of acute pancreatitis and also in the development of the systemic inflammatory response, being glutathione depletion, xanthine oxidase activation, and thiol oxidation in proteins critical features of the disease in the pancreas. On the other hand, the release of extracellular hemoglobin into the circulation from the ascitic fluid in severe necrotizing pancreatitis enhances lipid peroxidation in plasma and the inflammatory infiltrate into the lung and up-regulates the HIF-VEGF pathway, contributing to the systemic inflammatory response. Therefore, redox signaling and oxidative stress contribute to the local and systemic inflammatory response during acute pancreatitis.

Interleukin-6 is associated with obesity, central fat distribution, and disease severity in patients with acute pancreatitis

BACKGROUND/OBJECTIVE

Acute pancreatitis (AP) is a systemic inflammatory disease, and cytokines are suggested to be related to the course of AP. Obesity and central fat distribution are considered to have been associated with severe AP. This study investigated the profile of inflammatory cytokines in AP to determine how they are related to obesity, central fat distribution, and AP severity.

METHODS

Fifty-nine patients with AP were prospectively enrolled in the study. Body mass index and waist circumference were obtained at admission. Serum levels of inflammatory cytokines, IL-Iβ, IL-1ra, IL-6, TNF-α, sTNFR-I, and sTNFR-II, were measured on day 1 and 2 of AP.

RESULTS

Of the patients included in the study, 19 (32%) were overweight, 23 (39%) had central fat distribution, and 23 (39%) had moderate AP. IL-1ra and IL-6 were significantly higher in overweight patients compared with non-overweight patients. IL-1ra, IL-6, TNF-α, and sTNFR-I were significantly higher in patients with central fat distribution compared with patients with non-central fat distribution. IL-6, sTNFR-I, and sTNFR-II were significantly higher in patients with moderate pancreatitis compared to those with mild pancreatitis. Among the six cytokines, IL-6 was commonly elevated in patients with central fat distribution, overweight, and moderate AP. The areas under the receiver operating characteristic curves of IL-6 for predicting the association with overweight, central fat distribution, and AP severity were 0.678, 0.716, and 0.801, respectively (P < 0.05).

CONCLUSIONS

IL-6 is a good marker for AP severity and is associated with obesity and central fat distribution in AP patients.

Effects of soluble epoxide hydrolase deficiency on acute pancreatitis in mice

Background

Acute pancreatitis (AP) is a frequent gastrointestinal disorder that causes significant morbidity, and its incidence has been progressively increasing. AP starts as a local inflammation in the pancreas that often leads to systemic inflammatory response and complications. Soluble epoxide hydrolase (sEH) is a cytosolic enzyme whose inhibition in murine models has beneficial effects in inflammatory diseases, but its significance in AP remains unexplored.

Methodology/Principal Findings

To investigate whether sEH may have a causal role in AP we utilized Ephx2 knockout (KO) mice to determine the effects of sEH deficiency on cerulein- and arginine-induced AP. sEH expression increased at the protein and messenger RNA levels, as well as enzymatic activity in the early phase of cerulein- and arginine-induced AP in mice. In addition, amylase and lipase levels were lower in cerulein-treated Ephx2 KO mice compared with controls. Moreover, pancreatic mRNA and serum concentrations of the inflammatory cytokines IL-1B and IL-6 were lower in cerulein-treated Ephx2 KO mice compared with controls. Further, Ephx2 KO mice exhibited decreased cerulein- and arginine-induced NF-κB inflammatory response, MAPKs activation and decreased cell death. Conclusions -These findings demonstrate a novel role for sEH in the progression of cerulein- and arginine-induced AP.

Circulating cytokines in predicting development of severe acute pancreatitis

Acute pancreatitis is an inflammatory disease process which may present with clinical manifestations ranging from benign self-limited disease to overwhelming sepsis. The ability to predict outcome would be helpful in developing treatment plans, and possibly in stratifying patients for clinical trials.

Effects of hydroxyethyl starch and cell-free hemoglobin on microcirculation, tissue oxygenation, and survival in severe acute porcine pancreatitis: results of a randomized experimental trial

OBJECTIVE

Severe acute pancreatitis is a life-threatening disease with a high mortality; so far, no causal treatment is known. The aim of this study was to evaluate the therapeutic potential of hydroxyethyl starch (HES) and cell-free hemoglobin in an experimental model.

METHODS

Thirty-nine pigs were randomly assigned into 3 groups. Severe acute pancreatitis was induced by intraductal injection of glycodeoxycholic acid in combination with intravenous administration of cerulein. All animals were kept in isovolemic conditions by application of Ringer solution, 10% HES, or cell-free hemoglobin. The pancreatic microcirculation was evaluated over 8 hours. Thereafter, the animals were observed for 6 days followed by killing of the animals and histopathologic examination.

RESULTS

The administration of HES and cell-free hemoglobin led to improved microcirculation and tissue oxygenation compared with the Ringer's group. Consequently, the histopathologic damage was reduced (5.5 [3-8.5] vs 9.5 [7.5-11]; P < 0.001). In addition, the mean survival was significantly longer at 121 hours (95% confidence interval, 102-139) versus the Ringer group's 57 hours (95% confidence interval, 32-82; P < 0.001).

CONCLUSIONS

The administration of HES and cell-free hemoglobin can improve microcirculation in severe acute porcine pancreatitis, with consequent reduction in histopathologic damage and mortality. Therefore, this might represent an interesting therapeutic option in the treatment of severe acute pancreatitis.

The role of organ failure and infection in necrotizing pancreatitis: a prospective study

OBJECTIVE

To clarify the roles of organ failure and infection in the outcome of necrotizing pancreatitis.

BACKGROUND

Results of previous cohort studies that focused on the roles of infection and organ failure in acute pancreatitis are controversial.

METHODS

In this study, we collected the medical records of 447 patients with necrotizing pancreatitis from January 2009 to June 2012. Data associated with organ failure and infection were analyzed.

RESULTS

The overall mortality rate was 13% (58/447). Intervention was performed in 223 of 447 patients. Among these 223 patients, 134 were confirmed to be with infected necrosis by a positive culture. The mortality rate was 15% (13/89) in the sterile necrosis group and 18% (24/134) in the infected necrosis group (P = 0.52). A multivariate analysis of death predictors indicated that bacteremia (odds ratio [OR] = 2.76, 95% confidence interval [CI], 1.23-5.46, P < 0.001), age (OR = 1.07, 95% CI, 1.03-1.11, P < 0.001), American Society of Anesthesiologists class (OR = 3.56, 95% CI, 1.65-7.18, P = 0.001), persistent organ failure in the first week (OR = 16.72, 95% CI, 7.04-32.56, P < 0.001), and pancreatic necrosis (OR = 1.73, 95% CI, 1.14-2.98, P = 0.008) were significant factors.

CONCLUSIONS

Among patients with necrotizing pancreatitis, the effects of organ failure on mortality are more critical than those of infection. Bacteremia, age, American Society of Anesthesiologists class, persistent organ failure in the first week, and pancreatic necrosis were identified as the predictors of mortality.

Circulating cytokines in predicting development of severe acute pancreatitis

Introduction

Severe acute pancreatitis (AP) is associated with high morbidity and mortality. Early prediction of severe AP is needed to improve patient outcomes. The aim of the present study was to find novel cytokines or combinations of cytokines that can be used for the early identification of patients with AP at risk for severe disease.

Methods

We performed a prospective study of 163 nonconsecutive patients with AP, of whom 25 had severe AP according to the revised Atlanta criteria. Admission serum levels of 48 cytokines and growth factors were determined using Bio-Plex Pro Human Cytokine Assay 21-plex and 27-plex magnetic bead suspension panels. Admission plasma levels of C-reactive protein (CRP), creatinine and calcium were measured for comparison. In subgroup analyses, we assessed the cytokine profiles of patients with severe AP (n = 14) who did not have organ dysfunction (OD) upon admission (modified Marshall score <2).

Results

Of 14 cytokines elevated in the severe AP group, interleukin 6 (IL-6) and hepatocyte growth factor (HGF) levels were independent prognostic markers of severe AP. IL-6, HGF and a combination of them predicted severe AP with sensitivities of 56.0%, 60.0% and 72.0%, respectively, and specificities of 90.6%, 92.8% and 89.9%, respectively. The corresponding positive likelihood ratio (LR+) values were 5.9, 8.3 and 7.1, respectively. The predictive values of CRP, creatinine and calcium were comparable to those of the cytokines. In subgroup analyses of patients with severe AP and without OD upon admission, we found that IL-8, HGF and granulocyte colony-stimulating factor (G-CSF) levels predicted the development of severe AP, with G-CSF being the most accurate cytokine at a sensitivity of 35.7%, a specificity of 96.1% and a LR+ of 9.1.

Conclusions

IL-6 and HGF levels upon admission have prognostic value for severe AP which is similar to levels of CRP, creatinine and calcium. Although IL-6 and HGF, as either single or combined markers, were not perfect in identifying patients at risk for severe AP, the possibility that combining them with novel prognostic markers other than cytokines might improve prognostic accuracy needs to be studied. The accuracy of IL-8, HGF and G-CSF levels in predicting severe AP in patients without clinical signs of OD upon admission warrants larger studies.

FK866, a visfatin inhibitor, protects against acute lung injury after intestinal ischemia-reperfusion in mice via NF-κB pathway

OBJECTIVE

To determine whether administration of FK866, a competitive inhibitor of visfatin, attenuates acute lung injury induced by intestinal ischemia-reperfusion (I/R).

BACKGROUND

Acute lung injury, a frequent complication of intestinal I/R, is an inflammatory disorder of the lung, which is characterized by an overproduction of proinflammatory cytokines and increased permeability of the alveolar-capillary barrier, resulting in multiple organ dysfunction. Therefore, the development of novel and effective therapies for intestinal I/R is critical for the improvement of patient outcome. Visfatin, a 54-kDa secretory protein, is known as a proinflammatory cytokine and plays a deleterious role in inflammatory diseases.

METHODS

Male C57BL/6J mice were subjected to intestinal I/R induced by occlusion of the superior mesenteric artery for 90 minutes, followed by reperfusion. During reperfusion period, mice were treated with vehicle or FK866 (10 mg/kg of body weight) by an intraperitoneal injection. The levels of visfatin, proinflammatory mediators, and other markers were assessed 4 hours after reperfusion. In addition, survival study was conducted in intestinal I/R mice with or without FK866 treatment.

RESULTS

Plasma and lung visfatin protein levels were significantly increased after intestinal I/R. FK866 treatment significantly attenuated intestinal and lung injury by inhibiting proinflammatory cytokine production, cellular apoptosis, and NF-κB activation, hence improving survival rate. In vitro studies showed that macrophages treated with lipopolysaccharides upregulated visfatin expression, whereas FK866 inhibited proinflammatory cytokine production via modulation of the NF-κB pathway.

CONCLUSIONS

Collectively, these findings implicate FK866 as a novel therapeutic compound for intestinal I/R-induced attenuates acute lung injury via modulation of innate immune functions.