New insights into the pathogenesis of pancreatitis

Gene Regulation of Neutrophils Mediated Liver and Lung Injury through NETosis in Acute Pancreatitis

Acute pancreatitis (AP) is one of the most common gastrointestinal emergencies, often resulting in self-digestion, edema, hemorrhage, and even necrosis of pancreatic tissue. When AP progresses to severe acute pancreatitis (SAP), it often causes multi-organ damage, leading to a high mortality rate. However, the molecular mechanisms underlying SAP-mediated organ damage remain unclear. This study aims to systematically mine SAP data from public databases and combine experimental validation to identify key molecules involved in multi-organ damage caused by SAP. Retrieve transcriptomic data of mice pancreatic tissue for AP, lung and liver tissue for SAP, and corresponding normal tissue from the Gene Expression Omnibus (GEO) database. Conduct gene differential analysis using Limma and DEseq2 methods. Perform enrichment analysis using the clusterProfiler package in R software. Score immune cells and immune status in various organs using single-sample gene set enrichment analysis (ssGSEA). Evaluate mRNA expression levels of core genes using reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Validate serum amylase, TNF-α, IL-1β, and IL-6 levels in peripheral blood using enzyme-linked immunosorbent assay (ELISA), and detect the formation of neutrophil extracellular traps (NETs) in mice pancreatic, liver, and lung tissues using immunofluorescence. Differential analysis reveals that 46 genes exhibit expression dysregulation in mice pancreatic tissue for AP, liver and lung tissue for SAP, as well as peripheral blood in humans. Functional enrichment analysis indicates that these genes are primarily associated with neutrophil-related biological processes. ROC curve analysis indicates that 12 neutrophil-related genes have diagnostic potential for SAP. Immune infiltration analysis reveals high neutrophil infiltration in various organs affected by SAP. Single-cell sequencing analysis shows that these genes are predominantly expressed in neutrophils and macrophages. FPR1, ITGAM, and C5AR1 are identified as key genes involved in the formation of NETs and activation of neutrophils. qPCR and IHC results demonstrate upregulation of FPR1, ITGAM, and C5AR1 expression in pancreatic, liver, and lung tissues of mice with SAP. Immunofluorescence staining shows increased levels of neutrophils and NETs in SAP mice. Inhibition of NETs formation can alleviate the severity of SAP as well as the levels of inflammation in the liver and lung tissues. This study identified key genes involved in the formation of NETs, namely FPR1, ITGAM, and C5AR1, which are upregulated during multi-organ damage in SAP. Inhibition of NETs release effectively reduces the systemic inflammatory response and liver-lung damage in SAP. This research provides new therapeutic targets for the multi-organ damage associated with SAP.

Trypsin in pancreatitis: The culprit, a mediator, or epiphenomenon?

Pancreatitis is a common, life-threatening inflammatory disease of the exocrine pancreas. Its pathogenesis remains obscure, and no specific or effective treatment is available. Gallstones and alcohol excess are major etiologies of pancreatitis; in a small portion of patients the disease is hereditary. Pancreatitis is believed to be initiated by injured acinar cells (the main exocrine pancreas cell type), leading to parenchymal necrosis and local and systemic inflammation. The primary function of these cells is to produce, store, and secrete a variety of enzymes that break down all categories of nutrients. Most digestive enzymes, including all proteases, are secreted by acinar cells as inactive proforms (zymogens) and in physiological conditions are only activated when reaching the intestine. The generation of trypsin from inactive trypsinogen in the intestine plays a critical role in physiological activation of other zymogens. It was proposed that pancreatitis results from proteolytic autodigestion of the gland, mediated by premature/inappropriate trypsinogen activation within acinar cells. The intra-acinar trypsinogen activation is observed in experimental models of acute and chronic pancreatitis, and in human disease. On the basis of these observations, it has been considered the central pathogenic mechanism of pancreatitis - a concept with a century-old history. This review summarizes the data on trypsinogen activation in experimental and genetic rodent models of pancreatitis, particularly the more recent genetically engineered mouse models that mimic mutations associated with hereditary pancreatitis; analyzes the mechanisms mediating trypsinogen activation and protecting the pancreas against its' damaging effects; discusses the gaps in our knowledge, potential therapeutic approaches, and directions for future research. We conclude that trypsin is not the culprit in the disease pathogenesis but, at most, a mediator of some pancreatitis responses. Therefore, the search for effective therapies should focus on approaches to prevent or normalize other intra-acinar pathologic processes, such as defective autophagy leading to parenchymal cell death and unrelenting inflammation.

Acute pancreatitis as a risk factor of chronic pancreatitis and pancreatic cancer. An overview

This is an overview of relation between acute and chronic pancreatitis and between acute pancreatitis and pancreatic cancer. Acute pancreatitis and recurrent acute pancreatitis are an etiological factor of chronic pancreatitis. Population-based studies have calculated the risk of acute recurrent pancreatitis after the first attack of acute pancreatitis to be 20% and development of chronic pancreatitis after first attack of acute pancreatitis is 10%. An important risk factor is tobacco smoking. Acute and chronic pancreatitis are risk factors for pancreatic cancer. The risk of acute pancreatitis is related to the number of recurrences of acute pancreatitis, but not the etiology of acute pancreatitis. Acute pancreatitis, as well as chronic pancreatitis, are risk factors for pancreatic cancer. After an attack of acute pancreatitis or recurrent acute pancreatitis a patient should be regarded as a high risk.

Rhizoma Alismatis Decoction improved mitochondrial dysfunction to alleviate SASP by enhancing autophagy flux and apoptosis in hyperlipidemia acute pancreatitis

BACKGROUND

Acute pancreatitis (AP) is an inflammatory disorder of the exocrine pancreas, especially hyperlipidemia acute pancreatitis (HLAP) is the third leading cause of acute pancreatitis which is more severe with a greater incidence of persistent multiorgan failure. HLAP inflicts injury upon the organelles within the acinar cell, particularly mitochondria, the endolysosomal-autophagy system, and is accompanied by senescence-associated secretory phenotype (SASP). RAD, only two consists of Rhizoma Alismatis and Atractylodes macrocephala Rhizoma, which is best known for its ability to anti-inflammatory and lipid-lowering. Nevertheless, the mechanism by which RAD alleviates HLAP remains obscure, necessitating further investigation.

PURPOSE

The study aimed to assess the effects of the RAD on HLAP and to elucidate the underlying mechanism in vivo and in vitro, offering a potential medicine for clinical treatment for HLAP.

STUDY DESIGN AND METHODS

C57BL/6 mice with hyperlipidemia acute pancreatitis were induced by HFD and CER, then administrated with RAD. AR42J were stimulated by cerulein or conditioned medium and then cultured with RAD. Serums were analyzed to evaluate potential pancreas and liver damage. Furthermore, tissue samples were obtained for histological, and protein investigations by H&E, Oil red staining, and Western blot. In addition, western blot and immunofluorescent staining were utilized to estimate the effect of RAD on mitochondrial function, autophagy flux, and SASP.

RESULTS

In vivo, RAD considerably alleviated systemic inflammation while attenuating TC, TG, AMY, LPS, inflammatory cytokines, histopathology changes, oxidative damage, mitochondrial fission, and autophagy markers in HLAP mice. Impaired autophagy flux and mitochondrial dysfunction resulted in a significant enhancement of NLRP3 and IL-1β in the pancreas. RAD could reverse these changes. In vitro, RAD significantly restored mitochondrial membrane potential and oxidative phosphorylation levels. RAD decreased Beclin-1 and LC3-II expression and increased LAMP-1 and Parkin-Pink expression, which showed that RAD significantly ameliorated HLAP-induced damage to the mitochondria function by suppressing mitochondrial oxidative damage and enhancing autophagy flux and mitophagy to remove the damaged mitochondria. In addition, we found that RAD could up-regulate the expression of BAX, and Bad and down-regulate the expression of p16, and p21, indicating that RAD could promote damaged cell apoptosis and alleviate SASP.

CONCLUSIONS

This study revealed that RAD ameliorates mitochondrial function to alleviate SASP through enhancing autophagy flux, mitophagy, and apoptosis which provided a molecular basis for the advancement and development of protection strategies against HLAP.

MZB1 regulates cellular proliferation, mitochondrial dysfunction, and inflammation and targets the PI3K-Akt signaling pathway in acute pancreatitis

BACKGROUND

Acute pancreatitis (AP) is a pathological condition characterized by the premature release and activation of trypsinogens and other enzyme precursors. In severe cases, the mortality rates are in the range of 20-30% and may even be as high as 50%. Though various prophylaxes are available for AP, the mechanism of its progression is unclear. Marginal zone B and B-1 cell-specific protein 1 (MZB1) is found in the endoplasmic reticulum (ER) where it is expressed exclusively in the B cells there. MZB1 promotes proliferation, inhibits apoptosis, invasion, and inflammation, and mitigates mitochondrial damage in cells. However, the importance of MZB1 in AP has not yet been determined.

METHODS

Differentially expressed genes (DEGs) between healthy pancreatic cells and those affected by AP were identified using datasets from Gene Expression Omnibus (GEO) datasets. Relative differences in MZB1 expression between normal and diseased tissues and cells were validated in vivo using a rat AP model induced with 4% (w/v) sodium taurocholate and in vitro using the AR42J rat pancreatic cell line exposed to caerulein (CAE). Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2`-deoxyuridine (EdU) assays were performed to detect and compare normal and pathological cell proliferation. Flow cytometry was employed to assess and compare cellular apoptosis. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) were applied to evaluate the apoptotic factors Bax and Bcl. The inflammatory factors interleukin (IL)-6 and IL-1β were quantified using Enzyme-linked immunosorbent assay (ELISA) and qRT-PCR techniques. Mitochondrial function was evaluated using assays for reactive oxygen species (ROS) and tetramethylrhodamine methyl ester (TMRM). WB and qRT-PCR were utilized to measure the expression levels of the PI3K-Akt signaling pathway, followed by a rescue experiment involving the inhibitor of wortmannin.

RESULTS

MZB1 was upregulated in the AP cases screened from the GEO datasets, the rat AP model, and the AR42J cells exposed to CAE. Overexpression of MZB1 enhanced the growth and supressed the cell death of AR42J cells while also activating the PI3K-Akt signaling pathway. MZB1 knockdown led to mitochondrial dysfunction and exacerbated inflammation. The rescue experiment demonstrated that MZB1 enhanced proliferation and inhibited apoptosis, mitochondrial dysfunction, and inflammation in pancreatic cells through the PI3K-Akt pathway.

CONCLUSIONS

AP cells and tissues exhibited markedly elevated levels of MZB1 expression compared to their healthy counterparts. MZB1 overexpression promoted proliferation and supressed apoptosis, mitochondrial dysfunction, and inflammation in pancreatic cells through the positive regulation of the PI3K-Akt signaling pathway.

Recent insights about autophagy in pancreatitis

Acute pancreatitis is a common inflammatory gastrointestinal disease without any successful treatment. Pancreatic exocrine acinar cells have high rates of protein synthesis to produce and secrete large amounts of digestive enzymes. When the regulation of organelle and protein homeostasis is disrupted, it can lead to endoplasmic reticulum (ER) stress, damage to the mitochondria and improper intracellular trypsinogen activation, ultimately resulting in acinar cell damage and the onset of pancreatitis. To balance the homeostasis of organelles and adapt to protect themselves from organelle stress, cells use protective mechanisms such as autophagy. In the mouse pancreas, defective basal autophagy disrupts ER homoeostasis, leading to ER stress and trypsinogen activation, resulting in spontaneous pancreatitis. In this review, we discuss the regulation of autophagy and its physiological role in maintaining acinar cell homeostasis and function. We also summarise the current understanding of the mechanisms and the role of defective autophagy at multiple stages in experimental pancreatitis induced by cerulein or alcohol.

Repetitive Cerulein-Induced Chronic Pancreatitis in Growing Pigs-A Pilot Study

Chronic pancreatitis (CP) is an irreversible and progressive inflammatory disease. Knowledge on the development and progression of CP is limited. The goal of the study was to define the serum profile of pro-inflammatory cytokines and the cell antioxidant defense system (superoxidase dismutase-SOD, and reduced glutathione-GSH) over time in a cerulein-induced CP model and explore the impact of these changes on selected cytokines in the intestinal mucosa and pancreatic tissue, as well as on selected serum biochemical parameters. The mRNA expression of CLDN1 and CDH1 genes, and levels of Claudin-1 and E-cadherin, proteins of gut barrier, in the intestinal mucosa were determined via western blot analysis. The study showed moderate pathomorphological changes in the pigs' pancreas 43 days after the last cerulein injection. Blood serum levels of interleukin (IL)-1-beta, IL-6, tumor necrosis factor alpha (TNF-alpha), C-reactive protein (CRP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGTP), SOD and GSH were increased following cerulein injections. IL-1-beta, IL-6, TNF-alpha and GSH were also increased in jejunal mucosa and pancreatic tissue. In duodenum, decreased mRNA expression of CDH1 and level of E-cadherin and increased D-lactate, an indicator of leaky gut, indicating an inflammatory state, were observed. Based on the current results, we can conclude that repetitive cerulein injections in growing pigs not only led to CP over time, but also induced inflammation in the intestine. As a result of the inflammation, the intestinal barrier was impaired.

Surgical management of acute pancreatitis: Historical perspectives, challenges, and current management approaches

Acute pancreatitis (AP) is a serious condition presenting catastrophic consequences. In severe AP, the mortality rate is high, and some patients initially diagnosed with mild-to-moderate AP can progress to a life-threatening severe state. Treatment of AP has evolved over the years. Drainage was the first surgical procedure performed for AP; however, later, surgical approaches were replaced by more conservative approaches due to the availability of advanced medical care and improved understanding of the course of AP. Currently, surgery is used to manage several complications of AP, such as pseudocysts, pancreatic fistulas, and biliary tract obstruction. Patients who are unresponsive to conservative treatment or have complications are typically considered for surgical intervention. This review focuses on the surgical approaches (endoscopic, percutaneous, and open) that have been established in recent studies to treat this acute condition and summarizes the common management guidelines for AP, discussing the relevant indications, significance, and complications. It is evident that despite their reduced involvement, surgeons lead the multidisciplinary care of patients with AP; however, given the gaps in existing knowledge, more research is required to standardize surgical protocols for AP.

Gene Expression Profiling: Identification of Novel Pathways and Potential Biomarkers in Severe Acute Pancreatitis

BACKGROUND

Determining the risk of developing severe acute pancreatitis (AP) on presentation to hospital is difficult but vital to enable early management decisions that reduce morbidity and mortality. The objective of this study was to determine global gene expression profiles of patients with different acute pancreatitis severity to identify genes and molecular mechanisms involved in the pathogenesis of severe AP.

STUDY DESIGN

AP patients (n = 87) were recruited within 24 hours of admission to the Emergency Department and were confirmed to exhibit at least 2 of the following features: (1) abdominal pain characteristic of AP, (2) serum amylase and/or lipase more than 3-fold the upper laboratory limit considered normal, and/or (3) radiographically demonstrated AP on CT scan. Severity was defined according to the Revised Atlanta classification. Thirty-two healthy volunteers were also recruited and peripheral venous blood was collected for performing RNA-Seq.

RESULTS

In severe AP, 422 genes (185 upregulated, 237 downregulated) were significantly differentially expressed when compared with moderately severe and mild cases. Pathway analysis revealed changes in specific innate and adaptive immune, sepsis-related, and surface modification pathways in severe AP. Data-driven approaches revealed distinct gene expression groups (endotypes), which were not entirely overlapping with the clinical Atlanta classification. Importantly, severe and moderately severe AP patients clustered away from healthy controls, whereas mild AP patients did not exhibit any clear separation, suggesting distinct underlying mechanisms that may influence severity of AP.

CONCLUSION

There were significant differences in gene expression affecting the severity of AP, revealing a central role of specific immunological pathways. Despite the existence of patient endotypes, a 4-gene transcriptomic signature (S100A8, S100A9, MMP25, and MT-ND4L) was determined that can predict severe AP with an accuracy of 64%.

Piezo1-mediated stellate cell activation causes pressure-induced pancreatic fibrosis in mice

Pancreatic fibrosis is a complication of chronic pancreatitis and is a prominent feature of pancreatic cancer. Pancreatic fibrosis is commonly observed in patients with prolonged pancreatic duct obstruction, which elevates intrapancreatic pressure. We show here that increased pancreatic duct pressure causes fibrosis and describes the mechanism by which pressure increases deposition of extracellular matrix proteins and fibrosis. We found that pancreatic stellate cells (PSCs), the source of the extracellular matrix proteins in fibrosis, express the mechanically activated ion channel Piezo1. By increasing intracellular calcium, mechanical stress or the Piezo1 agonist Yoda1-activated PSCs manifest by loss of perinuclear fat droplets and increased TGF-β1, fibronectin, and type I collagen expression. These effects were blocked by the Piezo1 inhibitor GsMTx4 and absent in PSCs from mice with conditional genetic deletion of Piezo1 in stellate cells, as was pancreatic duct ligation-induced fibrosis. Although TRPV4 has been proposed to have direct mechanosensing properties, we discovered that PSCs from Trpv4-KO mice were protected against Yoda1-triggered activation. Moreover, mice devoid of TRPV4 were protected from pancreatic duct ligation-induced fibrosis. Thus, high pressure within the pancreas stimulates Piezo1 channel opening, and subsequent activation of TRPV4 leads to stellate cell activation and pressure-induced chronic pancreatitis and fibrosis.

The unfolded protein response: An emerging therapeutic target for pancreatitis and pancreatic ductal adenocarcinoma

Pancreatitis is a debilitating disease involving inflammation and fibrosis of the exocrine pancreas. Recurrent or chronic forms of pancreatitis are a significant risk factor for pancreatic ductal adenocarcinoma. While genetic factors have been identified for both pathologies, environmental stresses play a large role in their etiology. All cells have adapted mechanisms to handle acute environmental stress that alters energy demands. A common pathway involved in the stress response involves endoplasmic reticulum stress and the unfolded protein response (UPR). While rapidly activated by many external stressors, in the pancreas the UPR plays a fundamental biological role, likely due to the high protein demands in acinar cells. Despite this, increased UPR activity is observed in response to acute injury or following exposure to risk factors associated with pancreatitis and pancreatic cancer. Studies in animal and cell cultures models show the importance of affecting the UPR in the context of both diseases, and inhibitors have been developed for several specific mediators of the UPR. Given the importance of the UPR to normal acinar cell function, efforts to affect the UPR in the context of disease must be able to specifically target pathology vs. physiology. In this review, we highlight the importance of the UPR to normal and pathological conditions of the exocrine pancreas. We discuss recent studies suggesting the UPR may be involved in the initiation and progression of pancreatitis and PDAC, as well as contributing to chemoresistance that occurs in pancreatic cancer. Finally, we discuss the potential of targeting the UPR for treatment.

The diverse roles of TMEM16A Ca2+-activated Cl- channels in inflammation

Background

Transmembrane protein 16A (TMEM16A) Ca²⁺-activated Cl^- channels have diverse physiological functions, such as epithelial secretion of Cl^- and fluid and sensation of pain. Recent studies have demonstrated that TMEM16A contributes to the pathogenesis of infectious and non-infectious inflammatory diseases. However, the role of TMEM16A in inflammation has not been clearly elucidated.

Aim of review

In this review, we aimed to provide comprehensive information regarding the roles of TMEM16A in inflammation by summarizing the mechanisms underlying TMEM16A expression and activation under inflammatory conditions, in addition to exploring the diverse inflammatory signaling pathways activated by TMEM16A. This review attempts to develop the idea that TMEM16A plays a diverse role in inflammatory processes and contributes to inflammatory diseases in a cellular environment-dependent manner.

Key scientific concepts of review

Multiple inflammatory mediators, including cytokines (e.g., interleukin (IL)-4, IL-13, IL-6), histamine, bradykinin, and ATP/UTP, as well as bacterial and viral infections, promote TMEM16A expression and/or activity under inflammatory conditions. In addition, TMEM16A activates diverse inflammatory signaling pathways, including the IP₃R-mediated Ca²⁺ signaling pathway, the NF-κB signaling pathway, and the ERK signaling pathway, and contributes to the pathogenesis of many inflammatory diseases. These diseases include airway inflammatory diseases, lipopolysaccharide-induced intestinal epithelial barrier dysfunction, acute pancreatitis, and steatohepatitis. TMEM16A also plays multiple roles in inflammatory processes by increasing vascular permeability and leukocyte adhesion, promoting inflammatory cytokine release, and sensing inflammation-induced pain. Furthermore, TMEM16A plays its diverse pathological roles in different inflammatory diseases depending on the disease severity, proliferating status of the cells, and its interacting partners. We herein propose cellular environment-dependent mechanisms that explain the diverse roles of TMEM16A in inflammation.

Targeting purinergic receptors to suppress the cytokine storm induced by SARS-CoV-2 infection in pulmonary tissue

The etiological agent of coronavirus disease (COVID-19) is the new member of the Coronaviridae family, a severe acute respiratory syndrome coronavirus 2 virus (SARS-CoV-2), responsible for the pandemic that is plaguing the world. The single-stranded RNA virus is capable of infecting the respiratory tract, by binding the spike (S) protein on its viral surface to receptors for the angiotensin II-converting enzyme (ACE2), highly expressed in the pulmonary tissue, enabling the interaction of the virus with alveolar epithelial cells promoting endocytosis and replication of viral material. The infection triggers the activation of the immune system, increased purinergic signaling, and the release of cytokines as a defense mechanism, but the response can become exaggerated and prompt the so-called “cytokine storm”, developing cases such as severe acute respiratory syndrome (SARS). This is characterized by fever, cough, and difficulty breathing, which can progress to pneumonia, failure of different organs and death. Thus, the present review aims to compile and correlate the mechanisms involved between the immune and purinergic systems with COVID-19, since the modulation of purinergic receptors, such as A2A, A2B, and P2X7 expressed by immune cells, seems to be effective as a promising therapy, to reduce the severity of the disease, as well as aid in the treatment of acute lung diseases and other cases of generalized inflammation.

Clinical feature of severe fever with thrombocytopenia syndrome (SFTS)-associated encephalitis/encephalopathy: a retrospective study

BACKGROUND/OBJECTIVE

Severe fever with thrombocytopenia syndrome (SFTS) cause encephalitis/encephalopathy, but few reports were available. We aimed to investigate the incidence of encephalitis/encephalopathy in SFTS patients and to summarize clinical characteristics, laboratory findings and imaging features.

METHODS

We conducted a retrospective review of all patients with confirmed SFTS admitted to Nanjing Drum Tower Hospital, a tertiary hospital in Nanjing City, China, between January 2016 and July 2020. The patients were divided into two groups according to whether they had encephalitis/encephalopathy: encephalitis/encephalopathy group and non- encephalitis/encephalopathy group. Clinical data, laboratory findings, imaging characteristics, treatments and outcomes of these patients were collected and analyzed.

RESULTS

A total of 109 SFTS patients with were included, of whom 30 (27.5 %) developed encephalitis/encephalopathy. In-hospital mortality (43.3 %) was higher in encephalitis/encephalopathy group than non-encephalitis/encephalopathy group (12.7 %). Univariate logistic regression showed that cough, wheezing, dyspnoea, respiratory failure, vasopressors use, bacteremia, invasive pulmonary aspergillosis (IPA) diagnoses, PCT > 0.5 ug/L, CRP > 8 mg/L, AST > 200 U/L and serum amylase level > 80 U/L were the risk factors for the development of encephalitis/encephalopathy for SFTS patients. Multivariate logistic regression analysis identified bacteremia, PCT > 0.5 mg/L and serum amylase level > 80 U/L as independent predictors of encephalitis/ encephalopathy development for SFTS patients.

CONCLUSIONS

SFTS-associated encephalitis/encephalopathy has high morbidity and mortality. it was necessary to strengthen the screening of CSF testing and brain imaging after admission for SFTS patients who had symptoms of encephalitis/encephalopathy. SFTS patients with bacteremia, PCT > 0.5 ug/L or serum amylase level > 80 U/L should be warned to progress to encephalopathy.

Epidemiological and clinical characteristics of severe fever with thrombocytopenia syndrome in southern Anhui Province, 2011-2020

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever, and the causative pathogen, the SFTS virus (SFTSV), was first discovered in China in 2010. In this study, a retrospective analysis of 86 patients that diagnosed with SFTS from two five-year periods (2011-2015 and 2016-2020) that was performed to explore the changes in epidemiology, clinical characteristics, laboratory parameters and prognosis between those two periods. The results showed that there were significant differences in age, the proportion of farmers, geographical distribution, the incidence of multiple organ dysfunction, the decrease in thrombocyte count, and the elevations of serum AST and lipase levels between the two groups (p<0.05). Additionally, the case-fatality rate in the 2016-2020 group (16.7%) was higher than that in the 2011-2015 group (6.25%), although the difference was not significant. Our study shows that SFTS is broadly distributed across Anhui Province. The mortality rate is high. May to July was the peak of the epidemic, and farmers constituted a high-risk group. In recent years, thrombocytopenia has become more serious, and multiple organ dysfunction is more common. Clinicians need to further strengthen their knowledge of the changing epidemiological and clinical characteristics of this disease.

Silencing of CREB Inhibits HDAC2/TLR4/NF-κB Cascade to Relieve Severe Acute Pancreatitis-Induced Myocardial Injury

The purpose of the present study is to investigate the role of CREB in cardiomyocytes proliferation in regulation of HDAC2-dependent TLR4/NF-κB pathway in severe acute pancreatitis (SAP)-induced myocardial injury. The SAP rat model was developed by injecting sodium touracholate into SD rats and then infected with lentivirus vectors expressing sh-CREB in the presence/absence of LPS. The pathological alterations of rat pancreatic and cardiac tissues were observed by HE staining. TUNEL assay was used to study apoptosis of cardiomyocytes. Next, the loss- and gain-function assay was conducted in LPS-induced myocardial injury cardiomyocytes to define the roles of CREB, HDAC2, and TLR4 in cardiomyocyte proliferation, apoptosis, inflammation, and myocardial injury in vitro. ChIP assay was used to study the enrichment of CREB bound to HDAC2 promoter. RT-qPCR and Western blot analysis were used to detect the expressions of related mRNA and proteins in the NF-κB pathway, respectively. CREB was found to be overexpressed in both SAP tissues and cells. CREB directly bound to the promoter of HDAC2 and activated its expression. Overexpressed CREB or HDAC2 inhibited proliferation and promoted apoptosis of cardiomyocytes. Suppression of CREB inhibited the HDAC2/TLR4/NF-κB cascade to promote proliferation and inhibit apoptosis of cardiomyocytes. The in vitro results were validated in vivo experiments. Coherently, suppression of CREB can inhibit HDAC2/TLR4/NF-κB cascade to promote cardiomyocyte proliferation, thus ameliorating SAP-induced myocardial injury.

Necroptosis protects against exacerbation of acute pancreatitis

The sensing of various extrinsic stimuli triggers the receptor-interacting protein kinase-3 (RIPK3)-mediated signaling pathway, which leads to mixed-lineage kinase-like (MLKL) phosphorylation followed by necroptosis. Although necroptosis is a form of cell death and is involved in inflammatory conditions, the roles of necroptosis in acute pancreatitis (AP) remain unclear. In the current study, we administered caerulein to Ripk3- or Mlkl-deficient mice (Ripk3^−/− or Mlkl^−/− mice, respectively) and assessed the roles of necroptosis in AP. We found that Ripk3^−/− mice had significantly more severe pancreatic edema and inflammation associated with macrophage and neutrophil infiltration than control mice. Consistently, Mlkl^−/− mice were more susceptible to caerulein-induced AP, which occurred in a time- and dose-dependent manner, than control mice. Mlkl^−/− mice exhibit weight loss, edematous pancreatitis, necrotizing pancreatitis, and acinar cell dedifferentiation in response to tissue damage. Genetic deletion of Mlkl resulted in downregulation of the antiapoptotic genes Bclxl and Cflar in association with increases in the numbers of apoptotic cells, as detected by TUNEL assay. These findings suggest that RIPK3 and MLKL-mediated necroptosis exerts protective effects in AP and caution against the use of necroptosis inhibitors for AP treatment.

The role of procalcitonin in reducing antibiotics across the surgical pathway

Procalcitonin (PCT) is widely considered as a highly sensitive biomarker of bacterial infection, offering general and emergency surgeons a key tool in the management of surgical infections. A multidisciplinary task force of experts met in Bologna, Italy, on April 4, 2019, to clarify the key issues in the use of PCT across the surgical pathway. The panelists presented the statements developed for each of the main questions regarding the use of PCT across the surgical pathway. An agreement on the statements was reached by the Delphi method, and this document reports the executive summary of the final recommendations approved by the expert panel.

ACVIM consensus statement on pancreatitis in cats

Background

Pancreatitis in cats, although commonly diagnosed, still presents many diagnostic and management challenges.

Objective

To summarize the current literature as it relates to etiology, pathogenesis, diagnosis, and management of pancreatitis in cats and to arrive at clinically relevant suggestions for veterinary clinicians that are based on evidence, and where such evidence is lacking, based on consensus of experts in the field.

Animals

None.

Methods

A panel of 8 experts in the field (5 internists, 1 radiologist, 1 clinical pathologist, and 1 anatomic pathologist), with support from a librarian, was formed to assess and summarize evidence in the peer reviewed literature and complement it with consensus clinical recommendations.

Results

There was little literature on the etiology and pathogenesis of spontaneous pancreatitis in cats, but there was much in the literature about the disease in humans, along with some experimental evidence in cats and nonfeline species. Most evidence was in the area of diagnosis of pancreatitis in cats, which was summarized carefully. In contrast, there was little evidence on the management of pancreatitis in cats.

Conclusions and Clinical Importance

Pancreatitis is amenable to antemortem diagnosis by integrating all clinical and diagnostic information available, and recognizing that acute pancreatitis is far easier to diagnose than chronic pancreatitis. Although both forms of pancreatitis can be managed successfully in many cats, management measures are far less clearly defined for chronic pancreatitis.

Preeclampsia and the Risk of Pancreatitis: A Nationwide, Population-Based Cohort Study

Background

Preeclampsia is a multiple organ dysfunction during pregnancy, including hepatic, renal, and neurological dysfunction, and is defined as hypertension and proteinuria occurring after 20 weeks of pregnancy. Clinical features seen in preeclampsia are due to relatively poorly perfused placenta and maternal endothelial dysfunction. Some studies have found that preeclampsia may cause acute pancreatitis due to microvascular abnormalities and visceral ischemia. This retrospective cohort study used the Taiwanese National Health Insurance Research Databases (NHIRD) to study the relationship between preeclampsia and the risk of pancreatitis.

Methods

In total, 606,538 pregnant women were selected from the NHIRD between January 1, 1998 and December 31, 2010. They were divided into a preeclampsia cohort (n = 485,211) and a nonpreeclampsia cohort (n = 121,327). After adjusting for comorbidities that may induce pancreatitis, we analyzed and compared the incidence of pancreatitis in the two cohorts.

Results

The overall incidence of pancreatitis in the preeclampsia cohort was significantly higher than that in the control cohort (4.29 vs. 2.33 per 10,000 person-years). The adjusted HR of developing pancreatitis increased 1.68-fold (95% CI: 1.19-2.36) in the preeclampsia cohort. In addition, pregnant women with preeclampsia without comorbidities had a significantly high risk of pancreatitis (aHR = 1.83, 95% CI 1.27-2.63). The combined effect of preeclampsia and alcohol-related diseases resulted in the highest risk of pancreatitis (aHR = 43.4, 95% CI: 6.06-311.3).

Conclusion

Compared with patients without preeclampsia, the risk of pancreatitis in patients with preeclampsia is significantly increased after adjusting for demographics and comorbidities. The risk of pancreatitis is greatly increased when preeclampsia is accompanied by alcohol-related diseases, hepatitis C, gallstones, diabetes, or age of 26–35 years. Early identification and effective control of preeclampsia and the associated comorbidities can reduce the risk of pancreatitis and the associated morbidity and mortality.

Effects of Prophylactic Antibiotics on Length of Stay and Total Costs for Pediatric Acute Pancreatitis: A Nationwide Database Study in Japan

OBJECTIVES

Acute pancreatitis (AP) guidelines for adult patients do not recommend routine prophylactic use of antibiotics because of no clinical merit on mortality, infectious complications, or length of stay. Although the mortality of pediatric AP is low, no studies have explored the rationale for antibiotic use in pediatric patients. The aim of this study was to evaluate the effects of early prophylactic antibiotics on length of stay and total costs in pediatric patients.

METHODS

Using the Japanese Diagnosis Procedure Combination database from 2010 to 2017, we used the stabilized inverse probability of treatment weighting method using propensity scores to balance the background characteristics in the antibiotics group and the control group, and compared length of stay and total costs between the groups.

RESULTS

We found significant differences between the antibiotics group (n = 652) and the control group (n = 467) in length of stay (11 days vs 9 days; percent difference, 15.4%; 95% confidence interval, 5.0%-26.8%) and total costs (US $4085 vs US $3648; percent difference, 19.8%; 95% confidence interval, 8.0%-32.9%).

CONCLUSIONS

Prophylactic antibiotics were associated with longer length of stay and higher total costs. Our results do not support routine use of prophylactic antibiotics in pediatric AP populations.

A Double Edged Sword Role of Interleukin-22 in Wound Healing and Tissue Regeneration

Wound healing and tissue regeneration is an intricate biological process that involves repair of cellular damage and maintenance of tissue integrity. Cascades involved in wound healing and tissue regeneration highly overlap with cancer causing pathways. Usually, subsequent tissue damage events include release of a number of cytokines to accomplish post-trauma restoration. IL-22 is one of the cytokines that are immediately produced to initiate immune response against several tissue impairments. IL-22 is a fundamental mediator in inflammation, mucous production, protective role against pathogens, wound healing, and tissue regeneration. However, accumulating evidence suggests pivotal role of IL-22 in instigation of various cancers due to its pro-inflammatory and tissue repairing activity. In this review, we summarize how healing effects of IL-22, when executed in an uncontrollable fashion can lead to carcinogenesis.

A novel function of IRF9 in acute pancreatitis by modulating cell apoptosis, proliferation, migration, and suppressing SIRT1-p53

Acute pancreatitis (AP) is an inflammatory disease caused by the abnormal activation of pancreatic enzymes in the pancreas, with a considerably high morbidity and mortality. However, the etiological factor and pathogenesis of AP are still unclear. This study was aimed to explore the role and mechanism of interferon regulatory factor 9 (IRF9) in the occurrence of AP and to provide experimental and theoretical foundation for AP diagnosis and treatment. AP model in vitro was established by caerulein-induced group. Small interfering RNA (siRNA) was designed and constructed to silence IRF9 gene. After siRNA transfected and caerulein treated successfully, the expression levels of IRF9, SIRT1, and acetylated p53 (Ac-p53) were determined by qRT-PCR and Western blot. The apoptosis, proliferation, and migration of AR42J cells were checked by flow cytometry, MTT, and transwell assay. Dual-luciferase reporter assay was implemented to validate the regulatory effect of IRF9 on SIRT1. Here, our study showed that the expression of IRF9 and Ac-p53 was increased, SIRT1 was decreased, and cell apoptosis, proliferation, and migration of AR42J cells were increased after caerulein induced. IRF9 gene silencing upregulated SIRT1, downregulated Ac-p53, and inhibited cell apoptosis, proliferation, and migration. Dual-Luciferase reporter assay showed that IRF9 could negatively regulate SIRT1. The potential mechanism was that IRF9 could modulate cell apoptosis, proliferation, migration, and bind the promoter of SIRT1 to repress SIRT1-p53. It hinted that IRF9 showed a novel function in AP by modulating cell apoptosis, proliferation, migration, and suppressing SIRT1-p53. IRF9 might be a good potential treatment target for AP.

ATF6 aggravates acinar cell apoptosis and injury by regulating p53/AIFM2 transcription in Severe Acute Pancreatitis

Background: There is no curative therapy for severe acute pancreatitis (SAP) due to poor understanding of its molecular mechanisms. Endoplasmic reticulum (ER) stress is involved in SAP and increased expression of ATF6 has been detected in SAP patients. Here, we aimed to investigate the role of ATF6 in a preclinical SAP mouse model and characterize its regulatory mechanism. Methods: Pancreatic tissues of healthy and SAP patients were collected during surgery. Humanized PRSS1 transgenic mice were treated with caerulein to mimic the SAP development, which was crossed to an ATF6 knockout mouse line, and pancreatic tissues from the resulting pups were screened by proteomics. Adenovirus-mediated delivery to the pancreas of SAP mice was used for shRNA-based knockdown or overexpression. The potential functions and mechanisms of ATF6 were clarified by immunofluorescence, immunoelectron microscopy, Western blotting, qRT-PCR, ChIP-qPCR and luciferase reporter assay. Results: Increased expression of ATF6 was associated with elevated apoptosis, ER and mitochondrial disorder in pancreatic tissues from SAP patients and PRSS1 mice. Knockout of ATF6 in SAP mice attenuated acinar injury, apoptosis and ER disorder. AIFM2, known as a p53 target gene, was identified as a downstream regulatory partner of ATF6, whose expression was increased in SAP. Functionally, AIFM2 could reestablish the pathological disorder in SAP tissues in the absence of ATF6. p53 expression was also increased in SAP mice, which was downregulated by ATF6 knockout. p53 knockout significantly suppressed acinar apoptosis and injury in SAP model. Mechanistically, ATF6 promoted AIFM2 transcription by binding to p53 and AIFM2 promoters. Conclusion: These results reveal that ATF6/p53/AIFM2 pathway plays a critical role in acinar apoptosis during SAP progression, highlighting novel therapeutic target molecules for SAP.

Two-layer regulation of TRAF6 mediated by both TLR4/NF-kB signaling and miR-589-5p increases proinflammatory cytokines in the pathology of severe acute pancreatitis

Inflammation is a leading cause of severe acute pancreatitis (SAP). MicroRNAs (miRNAs) are emerging as important regulators involved in the pathogenesis of many diseases including pancreatitis. To identify miRNAs that contribute to the pathology of SAP, we carried out a miRNA-specific microarray analysis using the biopsies donated by SAP patients. We totally obtained 50 differentially expressed miRNAs, including 20 upregulated and 30 downregulated miRNAs, respectively. We focused our current study on revealing the downstream target and the upstream regulatory mechanism of miR-589-5p, the most downregulated miRNA in our candidate lists. Our prediction results indicated that miR-589-5p might target TRAF6 (tumor necrosis factor receptor-associated factor 6), a critical member of the TLR4/NF-kB (Toll-like receptor 4/nuclear transcription factor-kB) pathway. Using different strategies such as in vitro overexpression or downregulation of miR-589-5p and treatment with lipopolysaccharide (LPS), we found that the expression of TRAF6 was regulated by two-layer mechanisms. On the one hand, TRAF6 was transcriptionally controlled by a DNA methylation mediated downregulation of miR-589-5p. On the other hand, the activation of TLR4/NF-kB signaling also could increase the protein level of TRAF6. The increased TRAF6 aggravated the downstream signaling and caused the translocation of NF-kB subunits from the cytoplasm to the nucleus, where NF-kB transcription factors induced the expression of proinflammatory cytokine genes. The maturation and production of proinflammatory cytokines induced inflammatory response and caused the occurrence of SAP.

Significant Remodeling Affects the Circulating Glycosaminoglycan Profile in Adult Patients with both Severe and Mild Forms of Acute Pancreatitis

Acute pancreatitis (AP) manifests itself either as a mild, self-limiting inflammation or a severe, systemic inflammatory process that is associated with various complications and a high mortality rate. It is unknown whether these two forms of the disease can differ in the profile of circulating glycosaminoglycans, which are molecules with huge biological reactivity due to a high density of negative electric charge. Plasma glycosaminoglycans were characterized/quantified in 23 healthy controls, 32 patients with mild AP, and 15 individuals with severe disease using electrophoresis with enzymatic identification (chondroitin sulfate and heparan sulfate) or an ELISA-based test (hyaluronan). Moreover, the correlations between the glycosaminoglycan levels and clinical parameters were evaluated. Both forms of AP showed similar remodeling of the plasma profile of the sulfated glycosaminoglycans. In contrast, only in the patients with mild AP was the level of circulating hyaluronan significantly decreased as compared to the healthy controls. Both forms of AP are associated with systemic changes in the metabolism of glycosaminoglycans. However, the alterations in hyaluronan metabolism may contribute to the disease evolution. The circulating hyaluronan may have some clinical value to predict the severity of AP and to evaluate the clinical status of patients with severe AP.

Ca2+ Signaling in Exocrine Cells

Calcium (Ca²⁺) and cyclic AMP (cAMP) signaling cross talk and synergize to stimulate the cardinal functions of exocrine cells, regulated exocytosis, and fluid and electrolyte secretion. This physiological process requires the organization of the two signaling pathways into complexes at defined cellular domains and close placement. Such domains are formed by membrane contact sites (MCS). This review discusses the basic properties of Ca²⁺ signaling in exocrine cells, the role of MCS in the organization of cell signaling and in cross talk and synergism between the Ca²⁺ and cAMP signaling pathways and, finally, the mechanism by which the Ca²⁺ and cAMP pathways synergize to stimulate epithelial fluid and electrolyte secretion.

Prevention of Severe Acute Pancreatitis With Cyclooxygenase-2 Inhibitors: A Randomized Controlled Clinical Trial

OBJECTIVES

Severe acute pancreatitis (SAP) is still a big challenge. Accumulated data showed that overexpression of cyclooxygenase-2 (COX-2) in acute pancreatitis and experimental pancreatitis could be attenuated with COX-2 inhibitors. This study was aimed to evaluate whether the occurrence of SAP could be prevented by selective COX-2 inhibitors.

METHODS

A total of 190 patients with predicted SAP were randomized into convention group or convention plus COX-2 inhibitors (C+COX-2-Is) group. Besides conventional treatment to all patients in 2 groups, parecoxib (40 mg/d intravenous injection for 3 days) and celecoxib (200 mg oral or tube feeding twice daily for 7 days) were sequentially administrated to the patients in the C+COX-2-Is group. The primary outcome was predefined as the occurrence of SAP. The serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) for all of the patients were measured.

RESULTS

The occurrence of SAP in the C+COX-2-Is group was decreased 47.08% compared with the convention group, 21.05% (20/95) vs 39.78% (37/93), P = 0.005. A reduction of late local complications was also shown in the C+COX-2-Is group, 18.95% (18/93) vs 34.41% (32/95), P = 0.016. The serum levels of IL-6 and TNF-α were significantly lower in the C+COX-2-Is group than those in the convention group, P < 0.05. Parecoxib relieved abdominal pain more rapidly and decreased the consumption of meperidine. An incremental reduction of cost for 1% decrease of SAP occurrence was RMB475.

DISCUSSION

Sequential administration of parecoxib and celecoxib in patients with predicted SAP obtained about half-reduction of SAP occurrence through decreasing serum levels of TNF-α and IL-6. This regimen presented good cost-effectiveness.

Current trends in pharmacological approaches for treatment and management of acute pancreatitis – a review

Objectives

Acute pancreatitis (AP) is an inimical disorder associated with overall mortality rates between 10-15%. It is a disorder of the exocrine pancreas which is characterized by local and systemic inflammatory responses primarily driven by oxidative stress and death of pancreatic acinar cells. The severity of AP ranges from mild pancreatic edema with complete recuperative possibilities to serious systemic inflammatory response resulting in peripancreatic/pancreatic necrosis, multiple organ failure, and death.

Key findings

We have retrieved the potential alternative approaches that are developed lately for efficacious treatment of AP from the currently available literature and recently reported experimental studies. This review summarizes the need for alternative approaches and combinatorial treatment strategies to deal with AP based on literature search using specific key words in PubMed and ScienceDirect databases.

Summary

Since AP results from perturbations of multiple signaling pathways, the so called “monotargeted smart drugs” of the past decade is highly unlikely to be effective. Also, the conventional treatment approaches were mainly involved in providing palliative care instead of curing the disease. Hence, many researchers are beginning to focus on developing alternate therapies to treat AP effectively. This review also summarizes the recent trends in the combinatorial approaches available for AP treatment.

Association of total cholesterol with severe acute pancreatitis: A U-shaped relationship

BACKGROUND & AIMS

There is no consensus on relationship between total cholesterol levels and incidence of severe acute pancreatitis (SAP). The aim of this study was to investigate the relation between total cholesterol (TC) and the disease severity of acute pancreatitis.

METHODS

We conducted a cross-sectional study on patients with acute pancreatitis between April 2012 and December 2015 in a university hospital. Fasting blood total cholesterol (TC) was assayed within 24 h of admission, as well as 3-5 days, 7-9 days and 13-15 days during hospitalization. Time interval before admission, age, gender, Body Mass Index, hypertension, diabetes mellitus, alcohol consumption, smoking, etiology and albumin were recorded as potential confounding factors. To assess the pattern of relationship of TC and SAP, we used restricted cubic spline analysis with multivariable logistic regression analysis. We also compared total cholesterol concentrations between patients with or without SAP at different time points.

RESULTS

648 patients (median age: 47.5 years; 62.4% man) were enrolled. The incidence of SAP was 10%. A U-shaped association of TC level within 24 h of admission with severity was observed in acute pancreatitis. Patients with low TC levels (<160 mg/dL) and high TC levels (>240 mg/dL) had a significantly higher incidence of SAP and protracted hospital stays when compared to moderate TC levels (160-240 mg/dL). Low total cholesterol levels (OR 2.72; 95 %eCI 1.27-5.83; P = 0.01) and high total cholesterol levels (OR 2.54; 95 %eCI 1.09-5.89; P = 0.03), were still independently associated with development of SAP after adjusting for potential confounding factors. Longitudinal cohort study indicated that patients with SAP had lower total cholesterol concentrations among 3-15 days after admission compared to patients without SAP (P < 0.001).

CONCLUSIONS

Both low TC level (<160 mg/dL) and high TC (>240 mg/dL) within 24 h of admission is independently associated with an increased risk of SAP.

Meta-analysis and field synopsis of genetic variants associated with the risk and severity of acute pancreatitis

Background

Genetic risk factors can provide insight into susceptibility for acute pancreatitis (AP) and disease progression towards (infected) necrotizing pancreatitis and persistent organ failure. The aim of the study was to undertake a systematic review of the genetic evidence for AP.

Methods

Online databases (MEDLINE, Embase, BIOSIS, Web of Science, Cochrane Library) were searched to 8 February 2018. Studies that reported on genetic associations with AP susceptibility, severity and/or complications were eligible for inclusion. Meta‐analyses were performed of variants that were reported by at least two data sources. Venice criteria and Bayesian false‐discovery probability were applied to assess credibility.

Results

Ninety‐six studies reporting on 181 variants in 79 genes were identified. In agreement with previous meta‐analyses, credible associations were established for SPINK1 (odds ratio (OR) 2·87, 95 per cent c.i. 1·89 to 4·34), IL1B (OR 1·23, 1·06 to 1·42) and IL6 (OR 1·64, 1·15 to 2·32) and disease risk. In addition, two novel credible single‐nucleotide polymorphisms were identified in Asian populations: ALDH2 (OR 0·48, 0·36 to 0·64) and IL18 (OR 1·47, 1·18 to 1·82). Associations of variants in TNF, GSTP1 and CXCL8 genes with disease severity were identified, but were of low credibility.

Conclusion

Genetic risk factors in genes related to trypsin activation and innate immunity appear to be associated with susceptibility to and severity of AP.

Ca2+ Influx Channel Inhibitor SARAF Protects Mice From Acute Pancreatitis

BACKGROUND & AIMS

Pancreatitis is characterized by increased influx of Ca²⁺ into acinar cells, by unknown mechanisms. Inhibitors of Ca²⁺ influx channels could be effective in treating acute pancreatitis, but these have deleterious side effects that can result in death. We investigated the expression patterns and functions of acinar cell Ca²⁺ channels and factors that regulate them during development of acute pancreatitis, along with changes in the channel inactivator store-operated calcium entry-associated regulatory factor (SARAF). We investigated whether SARAF is a target for treatment of acute pancreatitis and its status in human with pancreatitis.

METHODS

We generated mice that expressed SARAF tagged with hemagglutinin, using CRISPR/Cas9 gene editing, and isolated acinar cells. We also performed studies with Saraf^-/- mice, Saraf^zf/zf mice, mice without disruption of Saraf (control mice), and mice that overexpress fluorescently labeled SARAF in acinar cells. We analyzed interactions between stromal interaction molecule 1 (STIM1) and SARAF in HEK cells stimulated with carbachol using fluorescence resonance energy transfer microscopy and immunoprecipitation. Mice were given injections of caerulein or L-arginine to induce pancreatitis. Pancreatic tissues and blood samples were collected and levels of serum amylase, trypsin, tissue damage, inflammatory mediators, and inflammatory cells were measured. We performed quantitative polymerase chain reaction analyses of pancreatic tissues from 6 organ donors without pancreatic disease (controls) and 8 patients with alcohol-associated pancreatitis.

RESULTS

Pancreatic levels of Ca²⁺ influx channels or STIM1 did not differ significantly between acinar cells from mice with vs. without pancreatitis. By contrast, pancreatic levels of Saraf messenger RNA and SARAF protein initially markedly increased but then decreased during cell stimulation or injection of mice with caerulein, resulting in excessive Ca²⁺ influx. STIM1 interacted stably with SARAF following stimulation of HEK or mouse acinar cells with physiologic levels of carbachol, but only transiently following stimulation with pathologic levels of carbachol, leading to excessive Ca²⁺ influx. We observed reduced levels of SARAF messenger RNA in pancreatic tissues from patients with pancreatitis, compared with controls. SARAF knockout mice developed more severe pancreatitis than control mice after administration of caerulein or L-arginine, and pancreatic acinar cells from these mice had significant increases in Ca²⁺ influx. Conversely, overexpression of SARAF in acini reduced Ca²⁺ influx, eliminated inflammation, and reduced severity of acute pancreatitis.

CONCLUSIONS

In mice with pancreatitis, SARAF initially increases but is then degraded, resulting in excessive, pathological Ca²⁺ influx by acinar cells. SARAF knockout mice develop more severe pancreatitis than control mice, whereas mice that express SARAF from a transgene in acinar cells develop less-severe pancreatitis. SARAF therefore appears to prevent pancreatic damage during development of acute pancreatitis. Strategies to stabilize or restore SARAF to acinar cells might be developed for treatment of pancreatitis.

Continuous veno-venous hemofiltration for severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis is associated with high rates of mortality and life-threatening complications. Continuous veno-venous hemofiltration (CVVH) has been used in some centers to reduce mortality and avoid local or systemic complications, however its efficiency and safety is uncertain.

OBJECTIVES

To assess the benefits and harms of CVVH in patients suffering from severe acute pancreatitis; to compare the effects of different CVVH techniques; and to evaluate the optimal time for delivery of CVVH.

SEARCH METHODS

We searched the Cochrane Library (2019, Issue 8), MEDLINE (1946 to 13 September 2019), Embase (1974 to 13 September 2019), and Science Citation Index Expanded (1982 to 13 September 2019).

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) that compared CVVH versus no CVVH in participants with severe acute pancreatitis. We also included RCTs that compared different types of CVVH and different schedules for CVVH in participants with severe acute pancreatitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified the trials for inclusion, collected the data, and assessed the risk of bias. We performed the meta-analyses using Review Manager 5. We calculated the risk ratio (RR) for dichotomous outcomes, and the mean difference (MD) for continuous outcomes, with 95% confidence intervals (CIs).

MAIN RESULTS

We included two studies, involving a total of 94 participants, in the review.Continuous veno-venous hemofiltration versus no interventionWe included one study in which 64 participants with severe acute pancreatitis were randomized to undergo CVVH (32 participants) or no intervention (32 participants). There were no deaths in either group (very low-quality evidence). Adverse events, length of stay in the intensive care unit (ICU), length of hospital stay, total hospital cost, and quality of life were not reported in the study.One type of continuous veno-venous hemofiltration versus a different type of continuous veno-venous hemofiltrationWe included one study in which 30 participants with severe acute pancreatitis were randomized to undergo high-volume CVVH (15 participants) or standard CVVH (15 participants). High-volume CVVH may lead to little or no difference in in-hospital mortality rates (20.0% in the high-volume CVVH group versus 33.3% in the standard CVVH group; risk ratio (RR) 0.60, 95% confidence interval (CI) 0.17 to 2.07; 30 participants; 1 study; low-quality evidence). We are uncertain whether high-volume hemofiltration reduces rates of adverse events (13.3% in both groups; RR 1.00, 95% CI 0.16 to 6.20; 30 participants; 1 study; very low-quality evidence). Length of ICU stay, length of hospital stay, total hospital cost, and quality of life were not reported in the study.

AUTHORS' CONCLUSIONS

The quality of the current evidence is very low or low. For both comparisons addressed in this review, data are sparse. It is unclear whether CVVH has any effect on mortality or complications in patients with severe acute pancreatitis. It is also unclear whether high-volume CVVH is superior, equivalent or inferior to standard CVVH in patients with severe acute pancreatitis.

Antibiotic therapy in acute pancreatitis: From global overuse to evidence based recommendations

BACKGROUND

Unwarranted administration of antibiotics in acute pancreatitis presents a global challenge. The clinical reasoning behind the misuse is poorly understood. Our aim was to investigate current clinical practices and develop recommendations that guide clinicians in prescribing antibiotic treatment in acute pancreatitis.

METHODS

Four methods were used. 1) Systematic data collection was performed to summarize current evidence; 2) a retrospective questionnaire was developed to understand the current global clinical practice; 3) five years of prospectively collected data were analysed to identify the clinical parameters used by medical teams in the decision making process, and finally; 4) the UpToDate Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was applied to provide evidence based recommendations for healthcare professionals.

RESULTS

The systematic literature search revealed no consensus on the start of AB therapy in patients with no bacterial culture test. Retrospective data collection on 9728 patients from 22 countries indicated a wide range (31-82%) of antibiotic use frequency in AP. Analysis of 56 variables from 962 patients showed that clinicians initiate antibiotic therapy based on increased WBC and/or elevated CRP, lipase and amylase levels. The above mentioned four laboratory parameters showed no association with infection in the early phase of acute pancreatitis. Instead, procalcitonin levels proved to be a better biomarker of early infection. Patients with suspected infection because of fever had no benefit from antibiotic therapy.

CONCLUSIONS

The authors formulated four consensus statements to urge reduction of unjustified antibiotic treatment in acute pancreatitis and to use procalcitonin rather than WBC or CRP as biomarkers to guide decision-making.

Early Intra-Acinar Events in Pathogenesis of Pancreatitis

Premature activation of digestive enzymes in the pancreas has been linked to development of pancreatitis for more than a century. Recent development of novel models to study the role of pathologic enzyme activation has led to advances in our understanding of the mechanisms of pancreatic injury. Colocalization of zymogen and lysosomal fraction occurs early after pancreatitis-causing stimulus. Cathepsin B activates trypsinogen in these colocalized organelles. Active trypsin increases permeability of these organelles resulting in leakage of cathepsin B into the cytosol leading to acinar cell death. Although trypsin-mediated cell death leads to pancreatic injury in early stages of pancreatitis, multiple parallel mechanisms, including activation of inflammatory cascades, endoplasmic reticulum stress, autophagy, and mitochondrial dysfunction in the acinar cells are now recognized to be important in driving the profound systemic inflammatory response and extensive pancreatic injury seen in acute pancreatitis. Chymotrypsin, another acinar protease, has recently been shown be play critical role in clearance of pathologically activated trypsin protecting against pancreatic injury. Mutations in trypsin and other genes thought to be associated with pathologic enzyme activation (such as serine protease inhibitor 1) have been found in familial forms of pancreatitis. Sustained intra-acinar activation of nuclear factor κB pathway seems to be key pathogenic mechanism in chronic pancreatitis. Better understanding of these mechanisms will hopefully allow us to improve treatment strategies in acute and chronic pancreatitis.

Melatonin treatment of pigs with acute pancreatitis reduces inflammatory reaction of pancreatic tissue and enhances fitness score of pigs: experimental research

Background

Severe acute pancreatitis is associated with high morbidity and mortality. Melatonin is known as the activator of antioxidant enzymes. The main purpose of this study was to evaluate the clinical effect of melatonin treatment in a pig model with induced acute pancreatitis.

Methods

In this study, acute pancreatitis was induced in 38 German domestic pigs (German Hybrid). After induction of acute pancreatitis, 18 animals were treated with melatonin. Intraoperative clinical data, postoperative blood parameters, fitness, and Porcine Well-being (PWB) score, and post-mortal histopathological data were analyzed in both study groups.

Results

The matching procedure created two groups (melatonin group and control group) which were very similar. The fitness and PWB score were postoperative significantly enhanced in the melatonin group as compared to the control group (p = 0.005 and p = 0.003). Additionally, histological analysis revealed that acinar necrosis, fat tissue necrosis, and edema were significantly reduced in the melatonin group as compared to the non-melatonin group (p = 0.025, p = 0.003, and p = 0.028).

Conclusions

Pigs, which were treated with melatonin, were characterized by higher fitness and PWB scores than those of the control group. Moreover, melatonin treatment reduces the acinar necrosis, fat tissue necrosis, and edema of pancreatic tissue. Thus, melatonin might be a useful therapeutic option in severe acute pancreatitis.

UBIAD1 Plays an Essential Role in the Survival of Pancreatic Acinar Cells

UbiA prenyltransferase domain-containing protein 1 (UBIAD1) is a vitamin K₂ biosynthetic enzyme. We previously showed the lethality of this enzyme in UBIAD1 knockout mice during the embryonic stage. However, the biological effects of UBIAD1 deficiency after birth remain unclear. In the present study, we used a tamoxifen-inducible systemic UBIAD1 knockout mouse model to determine the role of UBIAD1 in adult mice. UBIAD1 knockout resulted in the death of the mice within about 60 days of administration of tamoxifen. The pancreas presented with the most prominent abnormality in the tamoxifen-induced UBIAD1 knockout mice. The pancreas was reduced remarkably in size; furthermore, the pancreatic acinar cells disappeared and were replaced by vacuoles. Further analysis revealed that the vacuoles were adipocytes. UBIAD1 deficiency in the pancreatic acinar cells caused an increase in oxidative stress and autophagy, leading to apoptotic cell death in the tamoxifen-induced UBIAD 1 knockout mice. These results indicate that UBIAD1 is essential for maintaining the survival of pancreatic acinar cells in the pancreas.

Chemerin alleviates acute pancreatitis in the rat thorough modulation of NF-κB signal

OBJECTIVE

Chemerin, an adipokine, works as the chemoattractant for the immune cells. The role of chemerin in the inflammatory reaction is controversial. Chemerin has been shown to aggravate the inflammatory response, but other studies demonstrated its anti-inflammatory influence. This study assessed the effects of chemerin on acute pancreatitis (AP) in vivo and in vitro.

METHODS

For in vivo experiments male Wistar rats were used. For in vitro study rat pancreatic AR42J cells were employed. Chemerin (1, 5 or 10 μg/kg) was given to the rats prior to the induction of AP by subcutaneous caerulein infusion (25 μg/kg). For in vitro studies cells were subjected to caerulein (10 nM) with or without chemerin (100 nM). Serum amylase activity was measured by enzymatic method, serum TNFα concentration - by ELISA kit. Western-blot was used to examine cellular proteins.

RESULTS

AP was confirmed by histological examination. Chemerin given to AP rats decreased histological manifestations of AP, reduced serum amylase activity and TNFα concentration. In AR42J cells subjected to caerulein with addition of chemerin signal for TNFα was reduced comparing to the cultures treated with caerulein alone. Analysis of the dynamics of nuclear translocation for p50, p65 and Bcl-3 points out to NF-κB attenuation as a mechanism of observed anti-inflammatory action of chemerin.

CONCLUSION

Chemerin significantly alleviated severity of AP in the rat, this is possibly due to the inhibition of pro-inflammatory signaling in the pancreatic cells.

Accelerating the Drug Delivery Pipeline for Acute and Chronic Pancreatitis: Summary of the Working Group on Drug Development and Trials in Acute Pancreatitis at the National Institute of Diabetes and Digestive and Kidney Diseases Workshop

A workshop was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases to focus on research gaps and opportunities on drug development for pancreatitis. This conference was held on July 25, 2018, and structured into 3 working groups (WG): acute pancreatitis (AP) WG, recurrent AP WG, and chronic pancreatitis WG. This article reports the outcome of the work accomplished by the AP WG to provide the natural history, epidemiology, and current management of AP; inform about the role of preclinical models in therapy selection; and discuss clinical trial designs with clinical and patient-reported outcomes to test new therapies.

PTEN suppresses the inflammation, viability, and motility of AP-AR42J cells by activating the Wnt/β-catenin pathway

Acute pancreatitis (AP), a kind of common acute abdominal disease and typical chemical inflammation, is commonly caused by pancreatin digestion of the pancreas and surrounding tissues. The gene for phosphate and tension homology deleted on chromosome ten (PTEN) is a tumor suppressor that regulates numerous cellular processes. In the present study, we have elaborately investigated the effect of PTEN on the alleviating of AP and its underlying mechanisms. Firstly, we demonstrated an up-regulation of PTEN in the pancreatic tissues from AP rats by immunochemistry, qRT-PCR and western-blot assays. Subsequently, cellular experiments exhibited that PTEN has a significant inhibition effect on the proliferation, invasion and migration of AP cells. Further underlying mechanism studies showed that the growth of AP cells was mainly restrained by PTEN in the G1 phase through activation of the Wnt/β-catenin pathway, which can be demonstrated by the down-regulation of various pro-inflammatory cytokines such as IL-6, IL-10, TNF and IL-1β. Taking these results together, we can draw the conclusion that PTEN plays a significant role in suppressing the inflammation, viability and motility of acute pancreatitis and could be a potential target for AP therapies.

Acute pancreatitis (AP), a kind of common acute abdominal disease and typical chemical inflammation, is commonly caused by pancreatin digestion of the pancreas and surrounding tissues.

β-Arrestin1 alleviates acute pancreatitis via repression of NF-κBp65 activation

BACKGROUND AND AIM

β-Arrestins (β-arrs) are regulators and mediators of G protein-coupled receptor signaling that are functionally involved in inflammation. Nuclear factor-κB p65 (NF-κBp65) activation has been observed early in the onset of pancreatitis. However, the effect of β-arrs in acute pancreatitis (AP) is unclear. The aim of this study is to investigate whether β-arrs are involved in AP through activation of NF-κBp65.

METHODS

Acute pancreatitis was induced by either caerulein injection or choline-deficient supplemented with ethionine diet (CDE). β-arr1 wild-type and β-arr1 knockout mice were used in the experiment. The survival rate was calculated in the CDE model mice. Histological and western blot analyses were performed in the caerulein model. Inflammatory mediators were detected by real-time polymerase chain reaction in the caerulein-induced AP mice. Furthermore, AR42J and PANC-1 cell lines were used to further study the effects of β-arr1 in caerulein-induced pancreatic cells.

RESULTS

β-Arr1 but not β-arr2 is significantly downregulated in caerulein-induced AP in mice. Targeted deletion of β-arr1 notably upregulated expression of the pancreatic inflammatory mediators including tumor necrosis factor α and interleukin 1β as well as interleukin 6 and aggravated AP in caerulein-induced mice. β-Arr1 deficiency increased mortality in mice with CDE-induced AP. Further, β-arr1 deficiency enhanced caerulein-induced phosphorylation of NF-κBp65 both in vivo and in vitro.

CONCLUSION

β-Arr1 alleviates AP via repression of NF-κBp65 activation, and it is a potentially therapeutic target for AP.