Different profile of cytokine synthesis according to the severity of acute pancreatitis

Fire in the belly: A scoping review of the immunopathological mechanisms of acute pancreatitis

Introduction

Acute pancreatitis (AP) is characterised by an inflammatory response that in its most severe form can cause a systemic dysregulated immune response and progression to acute multi-organ dysfunction. The pathobiology of the disease is unclear and as a result no targeted, disease-modifying therapies exist. We performed a scoping review of data pertaining to the human immunology of AP to summarise the current field and to identify future research opportunities.

Methods

A scoping review of all clinical studies of AP immunology was performed across multiple databases. Studies were included if they were human studies of AP with an immunological outcome or intervention.

Results

205 studies met the inclusion criteria for the review. Severe AP is characterised by significant immune dysregulation compared to the milder form of the disease. Broadly, this immune dysfunction was categorised into: innate immune responses (including profound release of damage-associated molecular patterns and heightened activity of pattern recognition receptors), cytokine profile dysregulation (particularly IL-1, 6, 10 and TNF-α), lymphocyte abnormalities, paradoxical immunosuppression (including HLA-DR suppression and increased co-inhibitory molecule expression), and failure of the intestinal barrier function. Studies including interventions were also included. Several limitations in the existing literature have been identified; consolidation and consistency across studies is required if progress is to be made in our understanding of this disease.

Conclusions

AP, particularly the more severe spectrum of the disease, is characterised by a multifaceted immune response that drives tissue injury and contributes to the associated morbidity and mortality. Significant work is required to develop our understanding of the immunopathology of this disease if disease-modifying therapies are to be established.

Epigallocatechin-3-gallate reduces neutrophil extracellular trap formation and tissue injury in severe acute pancreatitis

Neutrophil extracellular traps (NETs) promote intra-acinar trypsin activation and tissue damage. Therefore, reducing NET formation can reduce tissue damage in severe acute pancreatitis (SAP). However, NET formation pathways may differ among disease models. In this study, we evaluated the role of the myeloperoxidase-neutrophil elastase (NE) pathway in NET formation in SAP. SAP was induced by intraperitoneal injection of cerulein and LPSs in mice, and NE activity was inhibited by GW311616. Pancreatic tissues were collected for multiplex immunofluorescence, scanning electron microscopy, and western blotting to detect NET formation and the effect of NE on citrullinated histone H3, followed by analyses of serum amylase and cytokine levels. Pretreatment with GW311616 significantly reduced NET formation, pancreatic tissue damage, and systemic inflammatory responses in SAP. Network pharmacology analyses using NE as the target revealed the monomeric compound epigallocatechin-3-gallate (EGCG). Binding between EGCG and NE was validated using molecular docking, and the ability of EGCG to inhibit NE activity was verified experimentally. NET formation by PMA-stimulated neutrophils was significantly reduced in vitro when the cells were pretreated with 40 μM EGCG. Pretreatment with EGCG significantly reduced NET formation, pancreatic tissue damage, and systemic inflammatory responses in vivo. These results reveal that NET formation requires the myeloperoxidase-NE pathway, and citrullination of histone H3 is affected by NE activity in SAP. EGCG shows therapeutic potential for affecting NE activity, NET formation, and systemic inflammation in SAP.

Favorable efficacy of adalimumab treatment in experimental acute pancreatitis model

BACKGROUND

Acute pancreatitis is a clinical picture with a wide range of symptoms from mild inflammation to multiorgan failure and death. The aim of this study is to investigate the effects of Adalimumab (ADA) on inflammation and apoptosis in a cerulein-induced acute pancreatitis model in rats.

METHODS

Experimental cerulein-induced acute pancreatitis model was created by applying 4 intraperitoneal cerulein injections at 1-h intervals. A total of 40 rats, 8 in each group, were randomly distributed into five groups. In the groups that ADA treatment was given, two different doses of ADA were administered 5 mg/kg and 20 mg/kg as low and high doses, respectively. The rats were sacrificed 12 h after the last intraperitoneal administration of ADA. Blood samples were obtained from each rat for amylase, IL-6, and IL-1β measurements. Hematoxylin and Eosin (H&E) stains were used to undertake the histopathological analysis of the pancreas. The terminal deoxynucleotidyl transferase-mediated nick-end-labeling (TUNEL) method was used to evaluate apoptosis.

RESULTS

: Plasma amylase, IL-6, and IL-1β levels were significantly elevated in acute pancreatitis groups (p < 0.05). It was determined that both low (5 mg/kg) and high doses (20 mg/kg) of ADA ameliorated the parameters (plasma amylase, IL-6, and IL-1β) (p < 0.05). Although significant improvements were detected in the Schoenberg scoring system and the apoptotic index from the TUNEL method after highdose ADA treatment, no significant amelioration was observed in the histopathological examinations in the low-dose ADA group.

DISCUSSION

: It has been determined that the administration of high-dose ADA effectively alleviated the symptoms of acute pancreatitis and reduced the level of apoptosis. In line with the findings of our study, we have predicted that high-dose (20 mg/kg) ADA can be used as an effective and safe drug in the treatment of patients with acute pancreatitis.

Protective Effects of Sodium Para-aminosalicylic Acid on Manganese-Induced Damage in Rat Pancreas

Sodium p-aminosalicylic acid (PAS-Na) has been previously shown to protect the brain from manganese (Mn)-induced toxicity. However, the efficacy of PAS-Na in protecting other organs from Mn toxicity and the mechanisms associated with this protection have yet to be addressed. Therefore, here, we assessed pancreatic damage in response to Mn treatment and the efficacy of PAS-Na in limiting this effect, along with specific mechanisms that mediate PAS-Na's protection. Mn exposure led to increased blood Mn content in dose- and time-dependent manner. Furthermore, subchronic Mn exposure (20 mg/kg for 8 weeks) led to pancreatic damage in a dose-dependent manner. In addition, the elevated Mn levels increased iron and decreased zinc and magnesium content in the pancreas. These effects were noted even 8 weeks after Mn exposure cessation. Mn exposure also affected the levels of amylase, lipase, and inflammatory factors such as tumor necrosis factor (TNF-α) and interleukin-1 β (IL-1β). PAS-Na significantly inhibited the increase in Mn concentration in both blood and pancreas, restored Mn-induced pancreatic damage, reversed the Mn-induced alterations in metal levels, and restored amylase and lipase concentrations. Taken together, we conclude that in rats, PAS-Na shows pharmacological efficacy in protecting the pancreas from Mn-induced damage.

Hydrogen: A Potential New Adjuvant Therapy for COVID-19 Patients

Hydrogen has been shown to have antioxidant, anti-inflammatory, hormone-regulating, and apoptosis-resistance properties, among others. Based on a review of the research, the use of hydrogen might reduce the destructive cytokine storm and lung injury caused by SARS-CoV-2 during COVID-19 (Corona Virus Disease 2019) in the early stage, stimulating ropy sputum drainage, and ultimately reducing the incidence of severe disease. Molecular hydrogen treatment has the potential to become a new adjuvant therapy for COVID-19, but its efficacy and safety require large clinical trials and further confirmation.

SRT1720 ameliorates sodium taurocholate-induced severe acute pancreatitis in rats by suppressing NF-κB signalling

Severe acute pancreatitis (SAP) is a medical emergency that is often associated with multiple organ failure and high mortality. Although an SAP diagnosis requires prompt treatment, therapeutic options remain limited. SRT1720 is a newly formulatedSIRT1 activator that exerts multiple pharmacological activities with beneficial health effects. However, its potential as an SAP treatment has not been explored. The current study assessed the effect of SRT1720 on a rat model of sodium taurocholate-induced SAP and explored the underlying mechanism. SAP was induced in rats by retrograde injection of a 3.5% sodium taurocholate solution (1 ml/kg) in the biliopancreatic duct. SRT1720 (5 mg/kg) was administered intraperitoneally after sodium taurocholate exposure. Serum samples were analysed for inflammatory cytokine levels and select enzymatic activities using the enzyme-linked immunosorbent assay and commercial enzyme activity assay kits, respectively; protein expression levels were evaluated by western blotting; mRNA levels of biomarkers were determined by quantitative real-time PCR; histopathological changes were analysed by haematoxylin and eosin staining and immunohistochemistry.SRT1720 treatment significantly reduced serum amylase, lipase, pancreatic histological scores, proinflammatory cytokine (TNF-α and IL-6) levels, and expression of NF-κB and p65 in sodium taurocholate-induced SAP rats. Importantly, the treatment stimulated SIRT1 and IκBα levels in pancreatic tissue. Our data suggest that SRT1720 protects rats from sodium taurocholate-induced SAP by suppressing the NF-κB signalling pathway.

Pharmacokinetics and pharmacodynamics of Shengjiang decoction in rats with acute pancreatitis for protecting against multiple organ injury

AIM

To explore the pharmacokinetics and pharmacodynamics of Shengjiang decoction (SJD) in rats with acute pancreatitis (AP) for protecting against multiple organ injury.

METHODS

An AP model was established by retrograde perfusion of 3.5% sodium taurocholate into the biliopancreatic duct, and a control group (CG) received 0.9% sodium chloride instead. Twelve male Sprague-Dawley rats were randomly divided into a CG treated with SJD (CG + SJD) and a model group treated with SJD (MG + SJD), both of which were orally administered with SJD (5 g/kg) 2 h after surgery. Blood samples were collected via the tail vein at 10, 20, and 40 min and 1, 2, 3, 4, 6, 8, and 12 h after a single dose of SJD to detect its main components using high-performance liquid chromatography-tandem mass spectrometry. The pharmacokinetic parameters were compared. In the pharmacodynamic experiment, 18 male Sprague-Dawley rats were randomly divided into a CG, an AP model group (MG), and an SJD treated AP group (SJDG). Serum amylase, lipase, and inflammatory cytokines were measured, and heart, lung, liver, spleen, pancreas, kidney, and intestine tissues were collected for pathological examination.

RESULTS

The MG + SJD displayed significantly shorter mean residence time (MRT) and higher clearance (CL) for emodin and aloe-emodin; significantly shorter time of maximum concentration and T_1/2 and a lower area under curve (AUC) for aloe-emodin; a significantly higher AUC and lower CL for rhein; and longer MRT and lower CL for chrysophanol than the CG + SJD. In the pharmacodynamic experiment, the amylase, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α levels in the MG were higher than those in the CG (P < 0.05). After the herbal decoction treatment, the SJDG had higher IL-10 and lower TNF-α levels than the MG (P < 0.05). The MG had the highest pathological scores, and the pathological scores of the lung, pancreas, kidney, and intestine in the SJDG were significantly lower than those in the MG (P < 0.05).

CONCLUSION

AP may have varying effects on the pharmacokinetics of the major SJD components in rats. SJD might alleviate pathological injuries of the lung, pancreas, kidney, and intestine in rats with AP via regulating pro- and anti- inflammatory responses, which might guide the clinical application of SJD for AP treatment.

Acinar injury and early cytokine response in human acute biliary pancreatitis

Clinical acute pancreatitis (AP) is marked by an early phase of systemic inflammatory response syndrome (SIRS) with multiorgan dysfunction (MODS), and a late phase characterized by sepsis with MODS. However, the mechanisms of acinar injury in human AP and the associated systemic inflammation are not clearly understood. This study, for the first time, evaluated the early interactions of bile acid induced human pancreatic acinar injury and the resulting cytokine response. We exposed freshly procured resected human pancreata to taurolithocolic acid (TLCS) and evaluated for acinar injury, cytokine release and interaction with peripheral blood mononuclear cells (PBMCs). We observed autophagy in acinar cells in response to TLCS exposure. There was also time-dependent release of IL-6, IL-8 and TNF-α from the injured acini that resulted in activation of PBMCs. We also observed that cytokines secreted by activated PBMCs resulted in acinar cell apoptosis and further cytokine release from them. Our data suggests that the earliest immune response in human AP originates within the acinar cell itself, which subsequently activates circulating PBMCs leading to SIRS. These findings need further detailed evaluation so that specific therapeutic targets to curb SIRS and resulting early adverse outcomes could be identified and tested.

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.

Glycyrrhizin suppresses the expressions of HMGB1 and relieves the severity of traumatic pancreatitis in rats

Background

High mobility group box 1 (HMGB1) plays important roles in a large variety of diseases; glycyrrhizin (GL) is recognized as an HMGB1 inhibitor. However, few studies have focused on whether glycyrrhizin can potentially improve the outcome of traumatic pancreatitis (TP) by inhibiting HMGB1.

Methods

A total of 60 male Wistar rats were randomly divided into three groups (n = 20 in each): Control group, TP group and TP-GL group. Pancreatic trauma was established with a custom-made biological impact machine-III, and GL was administered at 15 minutes after the accomplishment of operation. To determine survival rates during the first 7 days after injury, another 60 rats (n = 20 in each) were grouped and treated as mentioned above. At 24 hours of induction of TP, the histopathological changes in pancreas were evaluated and serum amylase levels were tested. Serum tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and HMGB1 were measured using enzyme linked immunosorbent assay. HMGB1 expressions in pancreas were measured using immunohistochemical staining, Western blot and Real-Time PCR analysis.

Results

Serum levels of HMGB1, TNF-α and IL-6 were increased dramatically in TP group at 24 hours after induction of TP. However, these indicators were reduced significantly by GL administration in TP-GL group comparing with TP group (P<0.05). Meanwhile, survival analysis showed that the seven-day survival rate in TP-GL group was significantly higher than that in TP group (85% versus 65%, P<0.05). GL treatment significantly decreased the pancreatic protein and mRNA expressions of HMGB1 and ameliorated the pancreatic injury in rats with TP.

Conclusions

Glycyrrhizin might play an important role in improving survival rates and ameliorating pancreatic injury of TP by suppression of the expressions of HMGB1 and other proinflammatory cytokine.

Early prediction of severe acute pancreatitis by urinary β-2 microglobulin/saposin B peak ratios on MALDI-TOF

The current methods for predicting severe acute pancreatitis (severe AP) are either complicated or lack efficient sensitivity and specificity. In this study, a simple and practical approach was developed to predict severe AP by using peak intensity ratio of urinary β-2 microglobulin (B2M) to saposin B (SB) on MALDI-TOF MS. Patients with B2M/SB ratio higher than 1.127 present severe AP symptom with a higher Ranson score, computed tomography (CT) grade and longer hospitalization with a sensitivity of 83.7% and specificity of 74.3%. Label-free quantitative proteomics by nanoLC-MS/MS was applied to urine of severe AP patients and found that severe AP is accompanied with kidney injury and inflammation. The measurement of B2M/SB ratios by MALDI-TOF MS could be a simple, accurate and rapid method to diagnose severe AP as well as to monitor AP progression.

High plasma levels of the pro-inflammatory cytokine IL-22 and the anti-inflammatory cytokines IL-10 and IL-1ra in acute pancreatitis

BACKGROUND/OBJECTIVES

Pancreatic acinar cells are major targets of IL-22. Our aim is to study early plasma levels of IL-22, of pro- and anti-inflammatory cytokines in acute pancreatitis, and their association with severity or necrosis infection.

METHODS

Consecutive patients admitted to the Department of Hepato-Gastroenterology at Poitiers University of Medicine Hospital (France) with a diagnosis of AP were prospectively enrolled. Plasma concentrations of IL-22, IL-6, IL-8, IL-1 α, IL-1β, TNF- α, IFN-γ, IL-17A, IL-10, IL-1ra and IL-4 were assessed by multiple immunoassay at the admission time. A thoracoabdominal contrast-enhanced CT scan was performed at day 2.

RESULTS

Sixty-two patients were included; 13 patients (21%) had a severe acute pancreatitis, 5 patients (8%) developed necrosis infection and 29 patients (47%) had pleural effusion. Plasma levels of IL-22 were high in AP (135 ± 31 vs 4.2 ± 1.8 pg/ml for controls, p < 0.05), but did not correlate with the severity of the disease, whereas IL-6, IL-10 and IL-1ra where enhanced in patients with severe acute pancreatitis and with pleural effusion. Patients who further developed necrosis infection had higher levels of IL-1ra at admission (p = 0.0004).

CONCLUSION

In acute pancreatitis, high plasma levels of IL-22 are observed, regardless the severity of the disease. In contrast, severe forms were associated with increased levels of IL-6, IL-10 and IL-1ra. The beneficial or deleterious role of IL-22 in AP remains to be further studied.

Rosiglitazone attenuates the severity of hyperlipidemic severe acute pancreatitis in rats

Peroxisome proliferator-activated receptor-γ (PPAR-γ) ligand regulates adipocyte differentiation and insulin sensitivity, and exerts antihyperlipidemic and anti-inflammatory effects. However, the mechanisms by which PPAR-γ ligands affect hyperlipidemia with severe acute pancreatitis (SAP) have not been fully elucidated. The present study investigated the effects of rosiglitazone, a PPAR-γ ligand, on hyperlipidemia with SAP in a rat model. The hyperlipidemia was induced with a high-fat diet and SAP was induced by the administration of sodium taurocholate (TCA). The hyperlipidemia was shown to aggravate the severity of the sodium taurocholate-induced SAP. However, rosiglitazone demonstrated significant antihyperlipidemic and anti-inflammatory effects in the rats with high-lipid diet-induced hyperlipidemia and SAP.

The natural flavonoid quercetin ameliorates cerulein-induced acute pancreatitis in mice

Many plant-derived flavonoids including quercetin exhibit antioxidant and antiinflammatory properties. Proinflammatory cytokines and oxidative stress play an important role in acute pancreatitis. This study aimed to evaluate the effect of quercetin on cerulein-induced acute pancreatitis in mice. Animal groups were pretreated with quercetin (25, 50, 100 mg/kg, per os (p.o.)), thalidomide (200 mg/kg, p.o.) or vehicle (2% dimethyl sulfoxide (DMSO)) 1 h before hourly (x5) intraperitoneal injections of cerulein. A saline (0.9%, NaCl)-treated control group was included for comparison. Cerulein significantly enhanced the serum levels of amylase and lipase, and pancreatic myeloperoxidase activities, malondialdehyde and the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6, as well as the pancreatic wet weight/body weight ratio. Cerulein significantly reduced the serum levels of IL-10. Histological assessment of the pancreas showed tissue edema, neutrophil infiltration, acinar vacuolization, and cell necrosis and a marked increase in the immunoreactivity staining for TNF-alpha. Pretreatment with quercetin or thalidomide significantly attenuated the severity of cerulein-induced acute pancreatitis as evidenced by effective reductions in the pancreatic wet weight/body weight ratio, biochemical indices, proinflammatory cytokines, myeloperoxidase activity, malondialdehyde formation, and an increase in antiinflammatory cytokine IL-10. Quercetin treatment also markedly suppressed the histological changes such as pancreatic edema, inflammatory cell infiltration, acinar cell necrosis, and the expression of TNF-alpha. Taken together, these results indicate that quercetin ameliorates the severity of cerulein-induced acute pancreatitis by acting as an antiinflammatory and antioxidant agent.

Summary of integrative medicine for severe acute pancreatitis: 26-year clinical experiences and a report of 1 561 cases

OBJECTIVE

To investigate the changing trends of clinical management for severe acute pancreatitis (SAP) with integrative medicine.

METHODS

Clinical data of 1 561 patients with SAP from 1980 to 2005 was retrospectively analyzed. The mortality and morbidity of complications were compared.

RESULTS

Of the 1 561 patients, 400 patients accepted surgical operation, while the rest were treated conservatively with integrative medicine. There was a change toward conservative management together with Chinese purgative herbal medication use after 1990 (22.4% from 1980-1990 compared with 45.5% from 1991-1993) because of high postoperative mortality. From 1994-2005, the treatment integrating Western medicine with Chinese herbal medications came to be preferred over the classic Western operation-based method. This change was associated with decreased morbidity (35.4% in 1980-1990 compared with 24.7% in 1991-1993 and 11.0% in 1994-2005, P<0.05) and lower mortality (40.52% of 1980-1990 compared with 17.17% of 1991-1993 and <10.25% of 1994-2005, P<0.05).

CONCLUSION

The combination of conservative management with Chinese herbal medicines is preferable to classic Western medicine treatment to reduce morbidity and mortality of SAP, while surgery becomes a supplemental option.

Pioglitazone: a promising therapeutic tool in sodium taurocholate-induced severe acute pancreatitis

BACKGROUND

Studies suggest that peroxisome proliferator-activated receptor γ(PPARγ) ligands may represent a therapeutic option in acute pancreatitis, yet most of them have been prophylactic administrated.

AIMS

To evaluate the therapeutic effect of pioglitazone in rats with severe acute pancreatitis induced by sodium taurocholate.

METHODS

Severe acute pancreatitis (SAP) was induced in male Sprague-Dawley rats by the retrograde injection of 5% sodium taurocholate into the pancreatic duct. After SAP was induced, pioglitazone was injected intraperitoneally and its role on the severity of inflammatory response and pancreatic injury was investigated. Amylase activity, inflammatory cytokines production, pathological changes of pancreas, PPARγ mRNA expression, and the survival rate were examined.

RESULTS

Treatment with pioglitazone decreased the level of amylase activity, proinflammatory factors IL-6 and TNF-α, ameliorated pancreatic histological score, and upregulated the expression of PPARγ mRNA. The survival rate in the early stage of severe acute pancreatitis was also improved.

CONCLUSIONS

Pioglitazone can be used as a therapeutic drug and relieve the damages caused by SAP, which suggests PPARγ ligand-pioglitazone offers a potent approach for the treatment of severe acute pancreatitis.

Human bone marrow-derived clonal mesenchymal stem cells inhibit inflammation and reduce acute pancreatitis in rats

BACKGROUND & AIMS

Acute pancreatitis (AP) has a high mortality rate; repetitive AP induces chronic AP and pancreatic adenocarcinoma. Mesenchymal stem cells (MSCs) have immunoregulatory effects and reduce inflammation. We developed a protocol to isolate human bone marrow-derived clonal MSCs (hcMSCs) from bone marrow aspirate and investigated the effects of these cells in rat models of mild and severe AP.

METHODS

Mild AP was induced in Sprague-Dawley rats by 3 intraperitoneal injections of cerulein (100 μg/kg), given at 2-hour intervals; severe AP was induced by intraparenchymal injection of 3% sodium taurocholate solution. hcMSCs were labeled with CM-1,1'-dioctadecyl-3,3,3'-tetramethylindo-carbocyanine perchloride and administered to rats through the tail vein.

RESULTS

hcMSCs underwent self-renewal and had multipotent differentiation capacities and immunoregulatory functions. Greater numbers of infused hcMSCs were detected in pancreas of rats with mild and severe AP than of control rats. Infused hcMSCs reduced acinar-cell degeneration, pancreatic edema, and inflammatory cell infiltration in each model of pancreatitis. The hcMSCs reduced expression of inflammation mediators and cytokines in rats with mild and severe AP. hcMSCs suppressed the mixed lymphocyte reaction and increased expression of Foxp3(+) (a marker of regulatory T cells) in cultured rat lymph node cells. Rats with mild or severe AP that were given infusions of hcMSCs had reduced numbers of CD3(+) T cells and increased expression of Foxp3(+) in pancreas tissues.

CONCLUSIONS

hcMSCs reduced inflammation and damage to pancreatic tissue in a rat model of AP; they reduced levels of cytokines and induced numbers of Foxp3(+) regulatory T cells. hcMSCs might be developed as a cell therapy for pancreatitis.

Flavocoxid, a dual inhibitor of cyclooxygenase-2 and 5-lipoxygenase, reduces pancreatic damage in an experimental model of acute pancreatitis

BACKGROUND AND PURPOSE

Acute pancreatitis is an autodigestive process resulting in acute inflammation of the pancreas. Accumulating evidence indicates the essential contribution of cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LOX) to acute pancreatitis. We studied the effects of flavocoxid, a plant-derived dual inhibitor of COX-2 and 5-LOX, in a model of caerulein (CER)-induced acute pancreatitis.

EXPERIMENTAL APPROACH

Rats were given CER (80 µg·kg⁻¹ for each of four injections at hourly intervals) or vehicle (Sham-CER). Animals were then randomized to receive flavocoxid (20 mg·kg⁻¹ i.p.) or vehicle, 30 min after the first CER injection. Two hours after the last CER injection, we evaluated damage to the pancreas by histological methods; serum levels of amylase, lipase, leukotriene (LT)B₄ and prostaglandin (PG)E₂ ; pancreatic expression of COX-2 and 5-LOX and tumour necrosis factor-α (TNF-α) gene expression by real-time polymerase chain reaction.

KEY RESULTS

Caerulein induced inflammatory changes in the pancreas and raised values of the other variables measured. In CER-treated animals, but not in those given saline, flavocoxid inhibited COX-2 and 5-LOX expression, reduced serum levels of lipase and amylase and the degree of pancreatic oedema. Treatment with flavocoxid blunted the increased pancreatic TNF-α mRNA expression, serum leukotriene B₄ and prostaglandin E₂ levels, and protected against histological damage in terms of vacuolization and leukocyte infiltration.

CONCLUSIONS AND IMPLICATIONS

Our results confirm the key role of both COX-2 and 5-LOX in the inflammatory response to acute pancreatitis. Flavocoxid may provide a potential therapeutic approach to the treatment of patients at high risk of developing this life-threatening condition.

Ameliorative effect of adalimumab on experimentally induced acute pancreatitis in rats

OBJECTIVES

In this study, the effects of adalimumab (ADA), a fully humanized IgG1 monoclonal antibody to tumor necrosis factor α, on experimentally acute pancreatitis (AP) were examined.

METHODS

Healthy Wistar rats (n = 32) were randomly divided into 4 groups: group 1, AP; group 2, AP + ADA; group 3, control (physiologic saline), and group 4, physiologic saline + ADA (n = 8/group). Acute pancreatitis was induced with a retrograde injection of 3% sodium (Na)-taurocholate into the common biliopancreatic duct. Adalimumab was simultaneously administered at 50 mg/kg intraperitoneally for groups 2 and 4. Physiologic saline was administered instead of Na-taurocholate for non-AP groups. After 24 hours, serum amylase, lactate dehydrogenase, pancreatic myeloperoxidase, and malondialdehyde activities, along with pancreatic histopathology, were examined.

RESULTS

Adalimumab treatment significantly decreased serum amylase activity (AP, 2778.25 ± 298.80; AP + ADA, 2143.13 ± 221.69; control, 1541.00 ± 148.39; ADA, 1143.00 ± 256.30 U/L; P < 0.001), lactate dehydrogenase activity (AP, 2978.37 ± 364.65; AP + ADA, 2582.75 ± 164.23; control 931.25 ± 135.93; ADA, 582.62 ± 99.37 U/L; P < 0.001), myeloperoxidase activity (AP, 1.44 ± 0.20; AP + ADA, 0.86 ± 0.01; control, 0.60 ± 0.17; ADA, 0.41 ± 0.00 U/g of wet tissue; P < 0.001), malondialdehyde activity (AP, 16.94 ± 3.98; AP + ADA, 7.66 ± 2.27; control, 9.07 ± 1.00; ADA, 3.58 ± 0.30 nmol/g; P < 0.01), and total histopathologic scores (AP, 2.75 ± 0.16; AP + ADA, 1.50 ± 0.19; control, 0.00 ± 0.00; ADA, 0.00 ± 0.00; P < 0.001).

CONCLUSIONS

These results support the idea that adalimumab might be beneficial for severity of AP.

Antioxidant inhibits HMGB1 expression and reduces pancreas injury in rats with severe acute pancreatitis

BACKGROUND

Pathogenesis of severe acute pancreatitis is still unclear, which leads to a lack of proper treatment in severe acute pancreatitis therapeutic strategy.

OBJECTIVE

To investigate the effect of treatment with antioxidant pyrrolidine dithiocarbamate on pancreas injury in rats with severe acute pancreatitis and its possible mechanism.

METHODS

A total of 144 male Sprague-Dawley rats were randomly allocated into a sham operation group (n=48), a severe acute pancreatitis group (n=48), and a pyrrolidine dithiocarbamate-treated group (n=48). All the rats were killed at 1, 3, 6, 12, 24, and 48 h after operation. The pancreas histopathologies were observed and serum amylase levels were tested. Meanwhile, the nuclear factor-kappaB activation, tumor necrosis factor-alpha levels and high-mobility group box protein-1 expression levels in pancreatic tissue were studied.

RESULTS

Animals receiving pyrrolidine dithiocarbamate had significantly improved pancreas histopathology and lower serum amylase levels (p<0.05). In the severe acute pancreatitis group, pancreas tumor necrosis factor-alpha levels reached a peak at 6 h after operation and afterwards rapidly declined to normal levels. However, high-mobility group box protein-1 levels in pancreatic tissue increased remarkably at the 12th hour, reached a peak at 24 h, and maintained up to 48 h post-severe acute pancreatitis. Compared to the severe acute pancreatitis group, the pancreas nuclear factor-kappaB activity, tumor necrosis factor-alpha, high-mobility group box protein-1 levels in the pyrrolidine dithiocarbamate-treated group all remarkably decreased (p<0.05).

CONCLUSIONS

High-mobility group box protein-1 seems to act as a late cytokine mediator in the pathogenesis of severe acute pancreatitis. Pyrrolidine dithiocarbamate might inhibit the activation of nuclear factor-kappaB to blockade tumor necrosis factor-alpha, thereby indirectly suppressing the high-mobility group box protein-1 and reducing pancreatic tissue damage in rats with severe acute pancreatitis.

Diagnostic accuracy of interleukin-6 and interleukin-8 in predicting severe acute pancreatitis: a meta-analysis

OBJECTIVES

The early identification of patients at risk for severe acute pancreatitis (SAP) is crucial. Serum markers of disease severity have been assessed including interleukin (IL)-6 and IL-8; however, their predictive accuracy has varied significantly across studies. We conducted a meta-analysis to assess the accuracy of IL-6 and IL-8 at predicting SAP.

METHODS

We identified relevant published articles and calculated pooled sensitivities, specificities and likelihood ratios using the random-effect model. We included values for days 1, 2 and 3 of presentation for IL-6 and for days 1 and 2 for IL-8. We also constructed summary receiver-operating curves and assessed the area under the curve (AUC) and the diagnostic odds ratios (DORs) as measures of diagnostic accuracy.

RESULTS

For IL-6, we included 7 reports for day 1 and 4 reports for days 2 and 3. For IL-8, we analyzed 5 studies for day 1 and 4 for day 2. The pooled IL-6 sensitivities ranged between 81.0 and 83.6% and specificities between 75.6 and 85.3% with positive likelihood ratios of 3.43, 4.90 and 4.40 for days 1, 2 and 3, respectively. The IL-8 pooled sensitivities were 65.8 and 70.9% with specificities of 66.5 and 91.3% for days 1 and 2 with positive likelihood ratios of 1.96 and 8.15. The IL-6 AUCs were 0.75, 0.88 and 0.85 for days 1, 2 and 3. The IL-8 AUCs were 0.73 and 0.91 for days 1 and 2. The DOR for IL-6 was higher than that of IL-8 on day 1.

CONCLUSION

IL-6 and IL-8 seem to perform at an acceptable level in predicting SAP. Larger confirmatory studies formally comparing this performance with that of more commonly used markers are needed.

Involvement of sensory nerves in the protective effect of growth hormone on acute pancreatitis

Growth hormone (GH) has been shown to protect the intestinal barrier integrity and to stimulate the production of insulin-like growth factor 1 (IGF-1), which inhibits the development of acute pancreatitis. Sensory nerves are implicated in the protection of pancreatic tissue against acute inflammation. The aim of this study was to investigate the influence of exogenous GH on acute pancreatitis (AP) and to assess the involvement of sensory nerves and IGF-1 in above effect. Studies were performed on Wistar rats. AP was induced by subcutaneous administration of caerulein (25mug/kg) to the conscious animals. GH (1 or 2mg/kg) was administered to the rats as an intraperitoneal injection 30min prior to the start of AP. To deactivate sensory nerves capsaicin was given at total dose of 100mg/kg 10days before the experiments. AP was confirmed by histological examination and manifested by the significant rises of pancreatic weight, and serum activities of lipase, TNFalpha and IL-10 (by 550%, 300% and 50%, respectively), whereas IGF-1 blood concentration was markedly reduced. Administration of GH prior to the caerulein infusion significantly increased GH, IGF-1 and IL-10 blood levels, attenuated harmful effects of AP and reduced histological manifestations of pancreatitis in the rats with intact sensory nerves. This was accompanied by the reduction of serum lipase, and TNFalpha activities. In the AP rats with capsaicin-deactivated sensory nerves GH failed to protect the pancreas against acute damage and, as a consequence of above deactivation, IGF-1 was low.

CONCLUSION

GH modulates the development of acute pancreatitis in the presence of active sensory nerves probably via stimulation of IGF-1 release.

Effects of etanercept on sodium taurocholate-induced acute pancreatitis in rats

In this study, we examined the effects of etanercept (ETA) on experimentally induced pancreatitis. Acute pancreatitis was induced with Na taurocholate. ETA was simultaneously administered to treatment groups. Serum amylase and lipase activity, pancreatic histopathology, apoptosis, malondialdehyde (MDA), and myeloperoxidase enzyme activity (MPO) were assessed. Although rats in the groups 1, 2, and 3 were sacrificed 24h later, groups 4, 5, and 6 were sacrificed 5 days later. ETA treatment significantly decreased serum amylase activity (nontreated, 2636.16+/-191.94; treated, 1898.71+/-262.53; control, 506.28+/-17.31 U/L, P<0.001), lipase activity (nontreated, 3049.67+/-972.65; treated, 2538.85+/-660.45; control, 88.57+/-7.54 U/L, P<0.001), histopathologic score (nontreated, 5.43+/-0.43; treated, 2.57+/-0.20; control, 0.71+/-0.18, P<0.001), MDA (nontreated, 105.77+/-13.29; treated, 92.89+/-10.39; control, 41.26+/-2.54 nmol/g, P<0.001), and MPO (nontreated, 0.64+/-1.15; treated, 0.59+/-0.13; control, 0.17+/-0.02 units/g/wet weight, P<0.001) activity in 24-h groups. In 5-day groups, ETA treatment decreased amylase activity (nontreated, 738.67+/-48.60; treated, 497.14+/-47.25; control, 389.00+/-9.17 U/L, P<0.001), lipase activity (nontreated, 101.33+/-39.32; treated, 34.57+/-7.29; control, 23.42+/-2.12 U/L, P<0.001), histopathologic score (nontreated, 5.43+/-0.43; treated, 3.71+/-0.68; control, 0.00+/-0.00, P<0.001), MDA (nontreated, 67.91+/-4.28; treated, 60.91+/-3.57; control, 14.85+/-1.16 nmol/g, P<0.001), and MPO (nontreated, 0.36+/-0.04; treated, 0.27+/-0.02; control, 0.14+/-0.02 units/g/wet weight, P<0.001) activity. Caspase-positive cells numbers around the necrosis significantly decreased by ETA treatment in both 24-h groups (nontreated, 74.28+/-3.26; treated, 67.00+/-1.15; control, 3.85+/-0.63, P<0.001) and 5-day groups (nontreated, 79.85+/-3.01; treated, 47.85+/-5.76; control, 2.22+/-0.63, P<0.001). These results showed that ETA has an ameliorating effect on sodium taurocholate-induced acute necrotic pancreatitis.

Cytokine genotypes in acute pancreatitis: association with etiology, severity, and cytokine levels in blood

The circumstances that determine how acute pancreatitis (AP) becomes severe are unknown. Differences in cytokine genetic encoding may determine the severity or influence the etiology of AP. This article investigates the relationship between different polymorphisms of tumor necrosis factor alpha (TNF-alpha), interleukin 1 (IL-1), IL-1 receptor antagonist, IL-6, and IL-10 with the severity and etiology of AP and the serum levels of the cytokine encoded.

METHODS

Patients with AP were included prospectively. Severity of the disease was determined according to Atlanta classification. Serum levels of these cytokines were determined within the first 72 hours after the onset of symptoms. The following polymorphisms were determined by polymerase chain reaction: IL-1a -889, IL-1b +3954, IL-1b -511, variable number tandem repeats, IL-6 -174, IL-6 -597, IL-10 -592, TNF-alpha 308, TNF-alpha 238, and TNF-B250.

RESULTS

Eighty-four patients were included. The GA genotype of the TNF-alpha 238 polymorphism was associated with more frequent respiratory failure and shock than the GG genotype. Gallstone pancreatitis was associated with the CC genotype of the IL-6 -174 CC polymorphism.

CONCLUSIONS

AG genotype of the TNF-alpha 238 polymorphism is associated with organic failure in patients with AP. The CC genotype of the IL-6 174 polymorphism is associated with biliary etiology of acute pancreatitis.

Obesity and fat distribution imply a greater systemic inflammatory response and a worse prognosis in acute pancreatitis

BACKGROUND AND AIMS

Acute pancreatitis (AP) is a systemic inflammatory disease. It is already known that obesity and central fat distribution are related to the severity of AP, but the intimate mechanism of this relationship remains unknown. Obesity and central fat distribution are associated with an inflammatory state that could amplify the systemic inflammatory response (SIR) in AP. The aim of this study was to investigate how obesity and body fat distribution correlate with the SIR and severity of AP.

METHODS

85 consecutive patients with AP were studied. Body mass index, body fat distribution and previous comorbidity were obtained at admission. The SIR was assessed by the serum levels of interleukin (IL)-1beta, IL-1ra, IL-6, IL-8, IL-10, IL-12p70, tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein. Serum concentrations of the previously mentioned cytokines were also determined in a control group of 40 healthy volunteers.

RESULTS

63 patients (74%) had mild AP and 22 patients (26%) had severe AP. All the cytokines except IL-12p70 and TNF-alpha were increased in the AP group in comparison with the control group. The SIR was significantly increased in patients with severe AP. Obese patients and patients with central fat distribution had significantly more comorbidity, a higher proportion of severe AP and more intense SIR. Patients with comorbidity had a significantly higher proportion of severe AP and more SIR.

CONCLUSION

The severity of AP in obese patients and in patients with central fat distribution seems to be related to the comorbidity and the amplification of SIR. and IAP.

Role of tumor necrosis factor-alpha in acute pancreatitis: from biological basis to clinical evidence

Tumor necrosis factor (TNF)-alpha is a pleiotropic cytokine that exerts host-damaging effects in different autoimmune and inflammatory diseases. It is a key regulator of other proinflammatory cytokines and of leukocyte adhesion molecules, and it is a priming activator of immune cells. In recent years, several research lines-mostly derived from animal models and in vitro studies-suggested that TNF-alpha plays a pivotal role in the pathogenesis of acute pancreatitis. In particular, it contributes to the systemic progression of the inflammatory response and to the end-organ dysfunction often observed in severe disease. Current clinical applications of TNF-alpha in acute pancreatitis include the assessment of blood concentrations to predict disease severity and to identify individuals prone to develop complications such as multiple organ failure and septic shock. However, TNF-alpha is rapidly cleared from the bloodstream, and sensitivity and overall accuracy of its measurement seem strictly time dependent, thereby being of potential prognostic value only in the first days after the onset of the disease. In parallel, TNF-alpha has been evaluated as a novel pharmacologic target for treating pancreatitis. Although promising results have been observed in the laboratory, transition to clinical practice seems problematic, in particular, in the light of divergent results obtained in sepsis trials. Therefore, in future clinical trials pertaining to TNF-alpha neutralization in acute pancreatitis, timing of intervention should be related to changes in TNF-alpha serum levels, and inclusion and exclusion criteria should be accurately selected to better define the population most likely to benefit.

Adjusting effects of baicalin for nuclear factor-kappaB and tumor necrosis factor-alpha on rats with caerulein-induced acute pancreatitis

Forty Wistar rats were divided into 5 groups, including the control group, the acute pancreatitis group (AP group, induced by intraperitoneal injections of caerulein), and the AP group treated with baicalin, the AP group treated with LPS, and the AP group treated with LPS and baicalin. Pathological damage of pancreatic tissue was scored with hematoxylin and eosin (HE) staining. The mRNA expression of TNF-α was measured with semiquantitative RT-PCR, and activation of NF-κB was detected with flow cytometry assay. It was shown in the results that the expression of TNF-α mRNA, activation of NF-κB, and pathological score of AP group were all obviously higher than those of control group (P < .01). In AP group treated with LPS, further rise of these values were observed (P < .01). In the AP group treated with baicalin, activation of NF-κB decreased (P < .05), and expression of TNF-α mRNA also obviously decreased (P < .01), while pancreatic pathological damage was alleviated at the same time (P < .01); similar results were observed in AP group treated with LPS and baicalin (P < .01), which indicated that baicalin might be applied to inhibit NF-κB activating and TNF-α expressing so as to treat AP.

Therapeutic effects of Caspase-1 inhibitors on acute lung injury in experimental severe acute pancreatitis

AIM: To assess the therapeutic effect of Caspase-1 inhibitors (ICE-I) on acute lung injury (ALI) in experimental severe acute pancreatitis (SAP).

METHODS: Forty-two SD rats were randomly divided into 3 groups: healthy controls (HC, n = 6); SAP-S group (n = 18); SAP-ICE-I group (n = 18). SAP was induced by retrograde infusion of 5% sodium taurocholate into the bile-pancreatic duct. HC rats underwent the same surgical procedures and duct cannulation without sodium taurocholate infusion. In SAP-S group, rats received the first intraperitoneal injection of isotonic saline 2 h after induction of acute pancreatitis and a repeated injection after 12 h. In SAP-ICE-I group, the rats were firstly given ICE inhibitors intraperitoneally 2 h after induction of pancreatitis. As in SAP-S group, the injection was repeated at 12 h. Serum IL-1β was measured by ELISA. Intrapulmonary expression of Caspase-1, IL-1β and IL-18 mRNA were detected by semi-quantitative RT-PCR. The wet/dry weight ratios and histopathological changes of the lungs were also evaluated.

RESULTS: Serum IL-1β levels in SAP-S group were 276.77 ± 44.92 pg/mL at 6 h, 308.99 ± 34.95 pg/mL at 12 h, and 311.60 ± 46.51 pg/mL at 18 h, which were increased significantly (P < 0.01, vs HC). In SAP-ICE-I group, those values were decreased significantly (P < 0.01, vs SAP-S). Intrapulmonary expression of Caspase-1, IL-1β and IL-18 mRNA were observed in the HC group, while they were increased significantly in the SAP-S group (P < 0.01, vs HC). The expression of IL-1β and IL-18 mRNA were decreased significantly in the SAP-ICE-I group (P < 0.01, vs SAP-S), whereas Caspase-1 mRNA expression had no significant difference (P > 0.05). The wet/dry weight ratios of the lungs in the SAP-S group were increased significantly (P < 0.05 at 6 h, P < 0.01 at 12 h and 18 h, vs HC) and they were decreased significantly in the SAP-ICE-I group (P < 0.05, vs SAP-S). Caspase-1 inhibitors ameliorated the severity of ALI in SAP.

CONCLUSION: Caspase-1 activation, and overproduction of IL-1β and IL-18 play an important role in the course of ALI, and Caspase-1 inhibition is effective for the treatment of ALI in experimental SAP.

Dexamethasone mediates protection against acute pancreatitis via upregulation of pancreatitis-associated proteins

AIM

To examine the influence of dexamethasone on pancreatitis-associated protein (PAP) gene expression using both in vitro and in vivo models of acute pancreatitis and to study how PAP gene expression correlates with severity of pancreatitis.

METHODS

In vitro, IL-6 stimulated pancreas acinar AR42J cells were cultured with increasing concentrations of dexamethasone and assayed for PAP expression (RT-PCR). In vivo, pancreatitis was induced in rats by retrograde injection of 40 g/L taurocholate into the pancreatic duct. Animals were pretreated with dexamethasone (2 mg/kg) daily or saline for 4 d. Pancreata and serum were harvested after 24 h and gene expression levels of PAP I, II and III were measured by RT-PCR. Severity of pancreatitis was based on serum amylase, pancreatic wet weight, and histopathological score.

RESULTS

In vitro, dexamethasone and IL-6 induced a marked transcription of PAP I, II and III genes in AR42J cells at 24 h (P < 0.05 for all comparisons). In vivo, pancreas mRNA levels of PAP I, II or III increased by 2.6-fold, 1.9-fold, and 1.3-fold respectively after dexamethasone treatment, compared with saline treated animals. Serum amylase levels and edema were significantly lower in the dexamethasone group compared with the saline group. Histopathologic evaluation revealed less inflammation and necrosis in pancreata obtained from dexamethasone treated animals (P < 0.05).

CONCLUSION

Dexamethasone significantly decreases the severity of pancreatitis. The protective mechanism of dexamethasone may be via upregulating PAP gene expression during injury.