Effect of platelet-activating factor antagonists (BN-52021, WEB-2170, and BB-882) on bacterial translocation in acute pancreatitis

Parecoxib Improves the Outcomes of Acute Mild and Moderate Pancreatitis: A 3-Year Matched Cohort Study Based on a Prospective Database

OBJECTIVES

The aim of this study was to evaluate the role of parecoxib in patients with different severities of acute pancreatitis (AP).

METHODS

A total of 772 eligible patients with AP were divided into 4 groups: mild and moderately AP (MAP) treated with parecoxib (group A, n = 236), MAP without parecoxib treatment (group B, n = 453), severe AP (SAP) treated with parecoxib (group C, n = 28), and SAP without parecoxib treatment (group D, n = 55). Patients in group A were exactly matched with patients in group B by propensity score matching, similar to the matching between group C and group D.

RESULTS

The morbidity of abdominal infection in group A was significantly lower as compared with that in group B (P < 0.050). The progression of MAP to SAP significantly decreased in group A than group B (P < 0.050). No significant differences were observed between group C and group D. The risk factors independently related to the progression of MAP included alcoholic/high-fat dietary (P = 0.028) and parecoxib administration (P = 0.011).

CONCLUSIONS

Early administration of parecoxib could reduce the morbidity of complications among patients with MAP. Parecoxib may prevent the progression of MAP to SAP and improve its outcomes.

Intestinal barrier dysfunction and increased COX-2 gene expression in the gut of elderly rats with acute pancreatitis

BACKGROUND/OBJECTIVES

The clinical course of acute pancreatitis can vary from mild to severe. In its most severe manifestation, acute pancreatitis is associated with an exacerbated systemic inflammatory response and high mortality rates. The severe form of acute pancreatitis is more frequent in elderly patients than in young patients, but the mechanisms underlying this difference are still under investigation.

METHODS

Rats were divided into two groups as follows: Group 1, young rats; and Group 2, old rats. Acute pancreatitis group was induced by a retrograde injection of a sodium taurocholate solution into the biliopancreatic duct. Using this model of acute pancreatic injury, we designed a study to investigate possible differences in microbial translocation and characteristics of the intestinal barrier between elderly and young rats.

RESULTS

There was a significantly higher number of bacterial colonies in the pancreas of elderly rats compared with young rats following pancreas injury, which was associated with a more severe local intestinal inflammatory response that included elevated gene expression of COX-2 and a decreased gene expression of tight junction proteins.

CONCLUSIONS

We conclude that intestinal damage during acute pancreatitis is exacerbated in elderly rats compared with young rats and that COX-2 inhibition could be a potential therapeutic target to offer tailored treatment for acute pancreatitis in the elderly.

Roles of BN52021 in platelet-activating factor pathway in inflammatory MS1 cells

AIM: To determine the effects of BN52021 on platelet-activating factor receptor (PAFR) signaling molecules under lipopolysaccharide (LPS)-induced inflammatory conditions in MS1 cells.

METHODS: MS1 cells (a mouse pancreatic islet endothelial cell line) were grown in Dulbecco’s modified Eagle’s medium supplemented with 10% fetal bovine serum, 2 mmol/L glutamine and 100 μg/mL penicillin/streptomycin in 5% CO₂ at 37 °C. After growth to confluency in media, the cells were processed for subsequent studies. The MS1 cells received 0, 0.1, 1 and 10 μg/mL LPS in this experiment. The viability/proliferation of the cells induced by LPS was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Apoptosis and necrosis of the cells under the inflammatory condition described previously were observed using Hoechst 33342-propidium iodide staining. Adenylate cyclase (AC), phospholipase A₂ (PLA₂), phospholipase Cβ (PLCβ), protein tyrosine kinase (PTK), G protein-coupled receptor kinases (GRK) and p38-mitogen-activated protein kinase (p38 MAPK) mRNA in the PAFR signaling pathway were measured by real-time polymerase chain reaction. The protein expression level of phosphorylated AC (p-AC), phosphorylated PLA₂ (p-PLA₂), phosphorylated PTK (p-PTK), phosphorylated p38 MAPK (p-p38 MAPK), PLCβ and GRK was measured using Western blotting analysis.

RESULTS: The activity of MS1 cells incubated with different concentrations of LPS for 6 h decreased significantly in the 1 μg/mL LPS group (0.49 ± 0.10 vs 0.67 ± 0.13, P < 0.05) and 10 μg/mL LPS group (0.44 ± 0.10 vs 0.67 ± 0.13, P < 0.001), but not in 0.1 μg/mL group. When the incubation time was extended to 12 h (0.33 ± 0.05, 0.32 ± 0.03 and 0.25 ± 0.03 vs 0.69 ± 0.01) and 24 h (0.31 ± 0.01, 0.29 ± 0.03 and 0.25 ± 0.01 vs 0.63 ± 0.01), MS1 cell activity decreased in all LPS concentration groups compared with the blank control (P < 0.001). BN52021 significantly improved the cell activity when its concentration reached 50 μmol/L compared with the group that received LPS treatment alone, which was consistent with the results obtained from fluorescence staining. The mRNAs levels of AC (4.02 ± 0.14 vs 1.00 ± 0.13), GRK (2.63 ± 0.03 vs 1.00 ± 0.12), p38 MAPK (3.87 ± 0.07 vs 1.00 ± 0.17), PLA₂ (3.31 ± 0.12 vs 1.00 ± 0.12), PLCβ (2.09 ± 0.08 vs 1.00 ± 0.06) and PTK (1.85 ± 0.07 vs 1.00 ± 0.11) were up-regulated after LPS stimulation as compared with the blank control (P < 0.05). The up-regulated mRNAs including AC (2.35 ± 0.13 vs 3.87 ± 0.08), GRK (1.17 ± 0.14 vs 2.65 ± 0.12), p38 MAPK (1.48 ± 0.18 vs 4.30 ± 0.07), PLCβ (1.69 ± 0.10 vs 2.41 ± 0.13) and PLA₂ (1.87 ± 0.11 vs 2.96 ± 0.08) were significantly suppressed by BN52021 except for that of PTK. The level of p-AC (1.11 ± 0.12 vs 0.65 ± 0.08), GRK (0.83 ± 0.07 vs 0.50 ± 0.03), PLCβ (0.83 ± 0.16 vs 0.50 ± 0.10) and p-p38 MAPK (0.74 ± 0.10 vs 0.38 ± 0.05) was up-regulated after LPS stimulation as compared with the blank control (P < 0.05). The up-regulated proteins, including p-AC (0.65 ± 0.15 vs 1.06 ± 0.14), GRK (0.47 ± 0.10 vs 0.80 ± 0.06), PLCβ (0.47 ± 0.04 vs 0.80 ± 0.19) and p-p38 MAPK (0.30 ± 0.10 vs 0.97 ± 0.05), was significantly suppressed by BN52021, but p-PLA₂ and p-PTK protein level were not suppressed.

CONCLUSION: BN52021 could effectively inhibit LPS-induced inflammation by down-regulating the mRNA and protein levels of AC, GRK, p38 MAPK, PLA₂ and PLCβ in the PAFR signaling pathway.

Reduction of intestinal mucosal immune function in heat-stressed rats and bacterial translocation

PURPOSE

The aim of this study was to further understand the effects and mechanism of heat stress on the intestinal mucosal immune system of the rat, including changes in the intestinal mucosal barrier and immune function and their effects on bacterial translocation.

MATERIALS AND METHODS

Sprague Dawley (SD) rats were randomly divided into control and heat-stress groups. Both groups were housed in a 25°C environment of 60% relative humidity. The heat-stress group was subjected to 40°C for 2 h daily over 3 days.

RESULTS

Compared with the control group villi length in the small intestines of the heat-stress group was shortened. Jejunal mucosa were seriously damaged and the number of goblet cells in the epithelia of the duodenum and jejunum was significantly reduced. Electron microscopy revealed intestinal mucosal disorder, a large number of exudates of inflammatory fibrous material, fuzzy tight junction structure between epithelial cells, and cell gap increases in the heat-stress group. Transcription of IFN-γ, IL-2, IL-4, and IL-10, was significantly reduced, as was that of the intestinal mucosal immune-related proteins TLR2, TLR4, and IgA. The number of CD3(+) T cells and CD3(+)CD4(+)CD8(-) T cells in the mesenteric lymph nodes (MLNs) was significantly lower, while the number of CD3(+)CD4(-)CD8(+) T cells was significantly increased. The bacteria isolated from the MLNs were Escherichia coli.

CONCLUSIONS

Heat stress damages rat intestinal mechanical and mucosal immune barriers, and reduces immune function of the intestinal mucosa and mesenteric lymphoid tissues, leading to bacterial translocation.

Do the effects of pentoxifylline on the inflammatory process and pancreatic infection justify its use in acute pancreatitis?

Severe acute pancreatitis is associated with high morbidity and mortality rates. At the present time, no specific therapy has been shown to be uniformly effective in reducing morbidity and mortality in this disease. The aim of this study was to determine the effects of pentoxifylline on the pancreatic and systemic inflammatory process, pancreatic infection, and mortality rate in severe acute pancreatitis in rats.

METHODS

One hundred and twenty male Wistar rats were divided into 3 groups: sham, pancreatitis, and pentoxifylline (acute pancreatitis induction plus administration of 25 mg/kg pentoxifylline). Inflammatory response was measured by histological studies, inflammatory cytokine production (IL-6, IL-10, and TNF-alpha), and mortality rate. Pancreatic infection was evaluated by bacterial cultures expressed in colony-forming units per gram.

RESULTS

Pentoxifylline-treated animals had a statistically significant reduction of inflammatory cytokine levels, pancreatic histological damage, occurrence of bacterial translocation and pancreatic infection (p < 0.05), associated with a significant reduction in mortality rate.

CONCLUSIONS

Pentoxifylline administration in this experimental model of acute pancreatitis reduces local and systemic inflammatory responses and decreases the pancreatic infection and the mortality rate.

G[alpha]i2 and G[alpha]q expression change in pancreatic tissues and BN52021 effects in rats with severe acute pancreatitis

OBJECTIVE

To investigate change of G[alpha]i2, G[alpha]q mRNA, and their proteins in severe acute pancreatitis (SAP) and BN52021 effects.

METHODS

Rats were assigned into negative-controlled group (NC), SAP-modeled group (SAP), and BN52051-remedial group (BN). Each group was assigned into 6 subgroups at different time points. G[alpha]i2, G[alpha]q mRNA, and their proteins were determined.

RESULTS

In the SAP group, G[alpha]i2 at 12 and 24 hours and G[alpha]q at 1 and 6 hours were remarkably higher than those in the NC group; in the BN Group, G[alpha]i2 is not remarkably different from that in the SAP group, but G[alpha]q at 1 and 6 hours was lower than those in the SAP group (P < 0.01), and G[alpha]i2 at 12 hours was higher than that in the NC group (P < 0.05), but G[alpha]q was not remarkably different from that in the NC group; in the SAP group, G[alpha]i2 and G[alpha]q proteins were higher than those in the NC group (P < 0.05); in the BN group, G[alpha]i2 proteins at 6, 12, and 24 hours and G[alpha]q proteins were lower than those in the SAP group (P < 0.05), and G[alpha]i2 and G[alpha]q proteins at each time phase point except 24 hours were higher than those in the NC group (P < 0.05).

CONCLUSIONS

G[alpha]i2, G[alpha]q mRNA, and their proteins in SAP increase. BN52021 decreases G[alpha]i2 and G[alpha]q.

Experimental model of severe acute pancreatitis in rabbits

PURPOSE: To develop an experimental model of severe acute pancreatitis in rabbits through a pancreatic ductal injection of sodium taurocholate. METHODS: Twenty-four albino rabbits of the New Zealand lineage were distributed into four groups of six animals (A, B, C and S). The rabbits of three experimental groups (A, B and C) were submitted to a laparatomy and received a pancreatic ductal injection of 1ml/kg sodium taurocholate 5%. Also, they were submitted to further laparatomies after 4h, 8h and 12h, respectively. The control group (S) was subdivided into two groups of three animals: in subgroup S1 only the pancreatic duct catheterization was performed whereas in subgroup S2 the pancreatic duct catheterization as well as an injection of 1ml/kg physiologic solution 0.9% were carried out. After 12 hours, the rabbits were evaluated. In the re-intervention, blood was collected to determine the amylasemia and a pancreatectomy was carried out to investigate interstitial infiltration, steatonecrosis and necrosis of the organ, using an optical microscope. RESULTS: There was an elevation of amylase in all groups thus proving the existence of acute pancreatitis. The size of the interlobular septum increased progressively with a greater variation between group S1 (0.13) and group C (0. 53) (p=0.035). While all the animals in group A exhibited focal cellular necrosis, it was more intense in the rabbits of group B and culminated with a high proportion of severe pancreatic necrosis in group C animals. The difference in the intensity of cellular necrosis showed statistic significance (p=0.001). CONCLUSION: The proposed experimental model demonstrated its reproducibility and effectiveness in producing severe acute pancreatitis in rabbits.

The use of animal models to study bacterial translocation during acute pancreatitis

Infection of pancreatic necrosis with intestinal flora is accepted to be a main predictor of outcome during severe acute pancreatitis. Bacterial translocation is the process whereby luminal bacteria migrate to extraintestinal sites. Animal models were proven indispensable in detecting three major aspects of bacterial translocation: small bowel bacterial overgrowth, mucosal barrier failure, and disturbed immune responses. Despite the progress made in the knowledge of bacterial translocation, the exact mechanism, origin and route of bacteria, and the optimal prophylactic and treatment strategies remain unclear. Methodological restrictions of animal models are likely to be the cause of this uncertainty. A literature review of animal models used to study bacterial translocation during acute pancreatitis demonstrates that many experimental techniques per se interfere with intestinal flora, mucosal barrier function, or immune response. Interference with these major aspects of bacterial translocation complicates interpretation of study results. This paper addresses these and other issues of animal models most frequently used to study bacterial translocation during acute pancreatitis.

Acute pancreatitis affects non-parenchymal liver cells by a mechanism dependent on platelet-activating factor

BACKGROUND/AIM

During acute experimental pancreatitis, inflammatory mediators/cytokines are released by the pancreas and enter the portal venous system, reaching the liver. We investigate some aspects of the liver cell function under conditions of acute pancreatitis and the effect of in vivo treatment with a selective platelet-activating factor (PAF) antagonist.

METHODS

Cells were isolated from Wistar rats 24 h after induction of acute pancreatitis by retrograde injection of sodium taurocholate into the main pancreatic duct. The non-parenchymal cell population was separated by Percoll gradient and the adherent cell population (Kupffer cells) obtained. The cells were cultured for 24 h and supernatants assayed for nitrite by Griess reaction and for tumour necrosis factor (TNF) by bioassay in L929 cells. The microbicidal activity was evaluated by killing of Candida albicans. The PAF antagonist WEB2170 (10 mg/kg i.v.) was administered 30 min before induction of pancreatitis.

RESULTS

We found that liver cells produce nitric oxide (NO) only under lipopolysaccharide stimulation and that WEB-2170 treatment reduces the NO production by liver cells in the pancreatitis group only. Cells from both groups produced TNF spontaneously, and the levels were further increased after lipopolysaccharide stimulation. WEB-2170 treatment did not affect the TNF levels. Moreover, killing of C. albicans by Kupffer cells wassignificantly increased by the PAF antagonist.

CONCLUSION

These results suggest that PAF released during acute pancreatitis upregulates the NO production by non-parenchymal liver cells and inhibits Kupffer cell microbicidal activity which could explain the increased bacterial dissemination observed in acute pancreatitis.

Effect of inhibition of prostaglandin E2 production on pancreatic infection in experimental acute pancreatitis

OBJECTIVE

Acute pancreatitis is one the important causes of systemic inflammatory response syndrome (SIRS). SIRS results in gut barrier dysfunction that allows bacterial translocation and pancreatic infection to occur. Indomethacin has been used to reduce inflammatory process and bacterial translocation in experimental models. The purpose of this study was to determine the effect of inhibition of prostaglandin E2 (PGE2) production on pancreatic infection.

MATERIALS AND METHODS

An experimental model of severe acute pancreatitis (AP) was utilized. The animals were divided into three groups: sham (surgical procedure without AP induction); pancreatitis (AP induction); and indomethacin (AP induction plus administration of 3 mg/kg of indomethacin). Serum levels of interleukin (IL)-6 and IL-10, PGE2, and tumor necrosis factor (TNF)-alpha were measured 2 h after the induction of AP. We analyzed the occurrence of pancreatic infection with bacterial cultures performed 24 h after the induction of AP. The occurrence of pancreatic infection (considered positive when the CFU/g was >105), pancreatic histologic analysis, and mortality rate were studied.

RESULTS

In spite of the reduction of IL-6, IL-10, and PGE2 levels in the indomethacin group, TNF-alpha level, bacterial translocation, and pancreatic infection were not influenced by administration of indomethacin. The inhibition of PGE2 production did not reduce pancreatic infection, histologic score, or mortality rate.

CONCLUSION

The inhibition of PGE2 production was not able to reduce the occurrence of pancreatic infection and does not have any beneficial effect in this experimental model. Further investigations will be necessary to discover a specific inhibitor that would make it possible to develop an anti-inflammatory therapy.

Inhibition of cyclooxygenase-2 in experimental severe acute pancreatitis

BACKGROUND

The standard treatment for acute pancreatitis (AP) is still based on supportive care. The search for a new drug that could change the natural history of the disease is a continuing challenge for many researchers. The aim of this study is to evaluate the effect of a cyclooxygenase-2 (COX-2) inhibitor on experimental AP in rats.

METHODS

The animals were divided into 2 groups: Group 1 (n = 30)-animals with taurocholate-induced AP treated with parecoxib (40 mg/kg). Group 2 (n = 30)-animals with taurocholate-induced AP that received saline. The COX-2 inhibitor (parecoxib) was injected immediately after AP induction, through the penis dorsal vein. The parameters evaluated were histology, serum levels of amylase, IL-6 and IL-10, and mortality rate.

RESULTS

The serum levels of IL-6 and IL-10 in the parecoxib-treated group were lower than the control group. The amylase serum levels and the mortality rate remained unchanged in the treated animals. Histologic morphology also was unaltered, except for fat necrosis, which was higher in parecoxib-treated rats.

CONCLUSION

Inhibition of Cox-2 decreases the systemic release of inflammatory cytokines, but has a poor effect on the direct pancreas injury caused by taurocholate.

Role of platelet-activating factor in pathogenesis of acute pancreatitis

Platelet-activating factor (PAF) is a potent proinflammatory phospholipid mediator that belongs to a family of biologically active, structurally related alkyl phosphoglycerides with diverse pathological and physiological effects. This bioactive phospholipid mediates processes as diverse as wound healing, physiological inflammation, angiogenesis, apoptosis, reproduction and long-term potentiation. PAF acts by binding to a specific G protein-coupled receptor to activate multiple intracellular signaling pathways. Since most cells both synthesize and release PAF and express PAF receptors, PAF has potent biological actions in a broad range of cell types and tissues. Inappropriate activation of this signaling pathway is associated with many diseases in which inflammation is thought to be one of the underlying features. Acute pancreatitis (AP) is a common inflammatory disease. The onset of AP is pancreatic autodigestion mediated by abnormal activation of pancreatic enzyme caused by multiple agents, which subsequently induce pancreatic and systemic inflammatory reactions. A number of experimental pancreatitis and clinical trials indicate that PAF does play a critical role in the pathogenesis of AP. Administration of PAF receptor antagonist can significantly reduce local and systemic events that occur in AP. This review focuses on the aspects that are more relevant to the pathogenesis of AP.

Local and systemic effects of hypertonic solution (NaCl 7.5%) in experimental acute pancreatitis

OBJECTIVES

Severe acute pancreatitis (AP) is characterized by hemodynamic alterations and a systemic inflammatory response, leading to a high mortality rate. Treatment of hemorrhagic shock with hypertonic saline solutions significantly reduces mortality through an improvement in the hemodynamic conditions and possibly by an anti-inflammatory effect. Therefore, hypertonic solutions could be effective in AP.

METHODS

Wistar rats were divided in 4 groups: group C, control, without AP; group NT, AP, without treatment; group NS, treatment with normal saline solution (NaCl 0.9%) 1 hour after AP; group HTS, treatment with hypertonic saline solution (NaCl 7.5%) 1 hour after AP. AP was induced by injection of 2.5% sodium taurocholate into the pancreatic duct. Mean arterial blood pressure (MAP) and heart rate were recorded at 0 and 2, 4, 24, and 48 hours after AP. After induction of AP, animals were killed at 2, 12, 24, and 48 hours for serum amylase, interleukin (IL)-6, and IL-10 analysis, pancreatic tissue culture and histologic analysis, oxidation and phosphorylation of liver mitochondria, pulmonary myeloperoxidase activity (MPO), and mortality study.

RESULTS

In animals of groups NS and NT, a significant decrease of MAP was observed 48 hours after AP (NS: 91 +/- 3 mm Hg; NT: 89 +/- 3 mm Hg) compared with baseline (C: 105 +/- 2 mm Hg) and to HTS group (HTS: 102 +/- 2 mm Hg; P < 0.05). In animals of group NT, NS, and HTS, serum IL-6 and IL-10 levels were significantly higher at 2 hours after AP compared with the control group. However, IL-6 levels at 12 hours after AP and IL-10 levels at 2 and 12 hours after AP were significant lower in group HTS compared with NS and NT groups (P < 0.05). In group HTS, a decrease of pulmonary MPO activity and of pancreatic infection was observed 24 hours after AP compared with NT and NS groups (P < 0.05). A significant reduction on pancreatic acinar necrosis and mitochondrial dysfunction was observed after 48 hours of AP in animals of group HTS compared with groups NT and NS (P < 0.05). A significant reduction on mortality was observed in HTS (0/14) compared with NS (6/17; 35%) and NT (7/20; 35%).

CONCLUSIONS

The administration of hypertonic saline solution in experimental AP attenuated hemodynamic alterations, decreased inflammatory cytokines, diminished systemic lesions and pancreatic acinar necrosis, prevented pancreatic infection, and reduced the mortality rate.

Effect of platelet activating factor on function of intestinal immunological barrier in young rats

AIM: To investigate the effect of platelet activating factor (PAF) on the content of secretory IgA (SIgA) in intestinal mucosa.

METHODS: The rats were intraperitoneally injected with different concentrations of PAF (50 and 65 µg/kg) at a dose of 1 µL/g. Double antibody-PEG radioimmunoassay was used to determine the amount of SIgA in the intestinal mucosa. The histological changes were detected by hematoxylin and Eosin staining under light microscope.

RESULTS: In the PAF65 group, the histological examination showed edema of the villus, capillary congestion of the lamina propria, extension of the subepithelial lymphatic channel, polymorphonuclear infiltration in enteric cavity, and shedding of the epithelial layer at 0.5, 1.5, and 3 h. Edema of the villus were still shown at 6 and 24 h. In the PAF50 group, edema of the villus, capillary congestion of the lamina propria were showed at 0.5 and 1.5 h. Edema of the villus were still shown at 3, 6 and 24 h. The content of SIgA was obviously decreased in the experimental group than that in the control group (0.31±0.03 mg/L, 0.40±0.10 mg/L, P < 0.01; 0.43±0.13 mg/L, 0.46±0.11mg/L, P < 0.05, in PAF50 group; 0.28±0.07 mg/L, 0.36±0.08 mg/L, P < 0.01, 0.40±0.11 mg/L, 0.42±0.06 mg/L, P < 0.05, in PAF65 group vs 0.66±0.10 mg/L in the control) at 0.5, 1.5, 3 and 6 h, respectively. The SIgA content decreased most at 0.5 h, but then gradually increased.

CONCLUSION: PAF can lead to damages of the intestinal immunologic barrier by decreasing the SIgA content.

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Changes of serum level of IL-15, IL-18 and sTNF-1R in patients with acute pancreatitis

AIM: To detect the serum level of IL-15, IL-18 and soluble tumor necrosis factor receptor-1 (sTNF-1R) in patients with acute pancreatitis (AP), as well as the correlation among the three factors in AP.

METHODS: According to the clinical diagnosis and criteria for acute pancreatitis, 26 patients with AP were divided into severe acute pancreatitis (SAP) group (n = 7) and mild acute pancreatitis (MAP) group (n = 19). Ten normal individuals were used as the control group (n = 10). The serum level of IL-15, IL-18 and sTNF-1R were detected by ELISA.

RESULTS: IL-15, IL-18 and STNF-1R in the SAP group was higher than that in the MAP group (IL-15, 42±19 vs 6±2 ng/L, P < 0.01; IL-18, 78±15 vs 28±13 ng/L, P < 0.01; sTNF-1R, 6 327±3 655 vs 832±329 ng/L, P < 0.01). sTNF-1R in the SAP and MAP group was higher than that in the control group (SAP vs the control group: 6 327±3 655 vs 545±123 ng/L, P < 0.01; MAP vs the control group: 832±329 vs 545±123 ng/L, P < 0.01). The results of IL-15 and IL-18 were similar to those of sTNF-1R, those in the MAP group were lower than that in the control group (MAP vs the control group, IL-18: 28±13 vs 66±10 ng/L, P < 0.01; IL-15: 6±2 vs 53±13 ng/L, P < 0.01). There was no significant difference between the SAP group and the control group (P > 0.05). In the MAP group, there was significant positive correlation between sTNF-1R and IL-18 (r = 0.98, P < 0.01), sTNF-1R and IL-15 (r = 0.823, P < 0.01), IL-18 and IL-15 (r = 0.95, P < 0.01), respectively. In the SAP group, there was significant positive correlation between IL-15 and IL-18 (r = 0.906, P < 0.01), sTNF-1R and IL-15 (r = 0.93, P < 0.01), sTNF-1R and IL-18 (r = 0.953, P < 0.01), respectively.

CONCLUSION: IL-15, IL-18 and sTNF-1R play important roles in the development of acute pancreatitis, and they may be valuable indexes to predict the severity of AP.