Severity Of Pancreatic Injury Research Articles

Pancreatic injury due to blunt trauma on CT: does retropancreatic fat tissue reduce the severity of pancreatic injury?

Pancreatic injuries from blunt abdominal trauma have a high mortality rate, often accompanied by injuries to adjacent organs. This study aims to investigate the relationship between the size of retropancreatic adipose tissue and the severity of pancreatic and adjacent organ injuries in patients with pancreatic trauma. We retrospectively screened computed tomography (CT) images of 34 patients (25 males, nine females, aged 13-69 years) and 34 controls (28 males, six females, aged 15-66 years) who suffered blunt abdominal trauma. The area of adipose tissue located posterior to the pancreatic body was measured in the axial plane for all subjects. The severity of pancreatic injury was assessed in terms of the injury site, the retropancreatic adipose tissue area, and the degree of other organ injuries. Pancreatic injuries were located in the head for 16 patients (23.5%), in the body for four patients (5.9%), and in the tail for 14 patients (20.6%). The retropancreatic fat area was found to be significantly smaller in patients with pancreatic trauma compared to controls (p<0.0001). Furthermore, the ratio of the retropancreatic fat area to the vertebral corpus area differed significantly between patients with and without pancreatic injuries (p=0.014). Retropancreatic adipose tissue protects the pancreatic body from the impacts of blunt abdominal trauma. An increased amount of retropancreatic adipose tissue is associated with a reduced rate of pancreatic injury.

Sphingosine 1-phosphate receptor 2 mediated early stages of pancreatic and systemic inflammatory responses via NF-kappa B activation in acute pancreatitis

In acute pancreatitis, activation of inflammatory signaling, including the nuclear factor-kappa B (NF-κB) pathway, within acinar cells is known to be an early intracellular event occurring in parallel with pathologic trypsinogen activation. Sphingosine 1-phosphate receptor 2 (S1PR2) plays a critical role in endothelial inflammation, and our previous studies reported that S1PR2 deficiency significantly reduced the inflammatory response in liver injury under cholestasis conditions. However, the role of S1PR2 in inflammatory signaling activation within acinar cells and inflammatory responses during acute pancreatitis has not been elucidated. Here we report that S1PR2 was upregulated in the whole pancreas during acute pancreatitis. Blockade of S1PR2 by pharmacologic inhibition of S1PR2 by JTE-013 or AAV-mediated knockdown of S1PR2 improved the severity of pancreatic injury, as indicated by a significant reduction in inflammation and acinar cells death in acute pancreatitis mice. Moreover, S1PR2 is the predominant S1PRs expressed in pancreatic acinar cells and mediates NF-κB activation and the early inflammatory response within acinar cells under acute pancreatitis conditions via ROCK signaling pathways, not extracellular signal-regulated kinase pathways or p38 mitogen-activated protein kinase pathways. In addition, S1PR2 mediated macrophage NF-κB activation, migration and polarization toward the M1 phenotype. Therefore, these results demonstrated that the S1PR2-mediated early inflammatory response in acinar cells promotes the progression of acute pancreatitis, successfully linking local events to the systematic inflammatory response and leading to a novel therapeutic target for acute pancreatitis aimed at halting the progression of the inflammatory response.4Upw5czRUXogyYiQEsPybuVideo

Adenosine Kinase Inhibition Prevents Severe Acute Pancreatitis via Suppressing Inflammation and Acinar Cell Necroptosis.

Background: Inflammatory disorder and acinar cell death contribute to the initiation and progression of severe acute pancreatitis (SAP). Adenosine kinase (ADK) has potential effects on both inflammation and cell death. However, the role of ADK in SAP remains to be explored. Methods: To establish an experimental SAP model, male C57BL/6 mice were intraperitoneally injected with cerulein (50 μg/kg, seven doses at hourly intervals) and LPS (10 mg/kg, at the last cerulein injection). For ADK inhibition, ABT702 (1.5 mg/kg) was intraperitoneally injected 1 h before cerulein treatment. The pancreas and serum were collected and analyzed to determine the severity of pancreatic injury and explore the potential pathophysiological mechanisms. Pancreatic acinar cells (AR42J) were used to explore the in vitro effects of ADK inhibition on cerulein–induced inflammation and necroptotic cell death. Results: ADK inhibition notably attenuated the severity of SAP, as indicated by the decreased serum amylase (7,416.76 ± 1,457.76 vs. 4,581.89 ± 1,175.04 U/L) and lipase (46.51 ± 11.50 vs. 32.94 ± 11.46 U/L) levels and fewer pancreatic histopathological alterations (histological scores: 6.433 ± 0.60 vs. 3.77 ± 0.70). MOMA-2 and CD11b staining confirmed that ADK inhibition prevented the infiltration of neutrophils and macrophages. The phosphorylation of nuclear factor-κB (NF-κB) was also reduced by ADK inhibition. ADK inhibition markedly limited the necrotic area of the pancreas and prevented the activation of the necroptotic signaling pathway. Endoplasmic reticulum (ER) stress was activated in the pancreas using the SAP model and cerulein–treated AR42J cells whereas ADK inhibition reversed the activation of ER stress both in vivo and in vitro. Moreover, the alleviating effects of ADK inhibition on ER stress, inflammation, and cell necroptosis were eliminated by the adenosine A2A receptor antagonist. Conclusion: ADK inhibition reduced inflammation and necroptotic acinar cell death in SAP via the adenosine A2A receptor/ER stress pathway, suggesting that ADK might be a potential therapeutic target for SAP.

Outcomes after resection versus non-resection management of penetrating grade III and IV pancreatic injury: A trauma quality improvement (TQIP) databank analysis

BackgroundHigh-grade traumatic pancreatic injuries are associated with significant morbidity and mortality. Non-resection management is associated with fewer complications in pediatric patients. The present study evaluates outcomes following resection versus non-resection management of severe pancreatic injury caused by penetrating trauma. MethodsA retrospective study of the Trauma Quality Improvement Program (TQIP) database was performed from 1/2010 to 12/2014. Patients with AAST Organ Injury Scale pancreatic grade III and IV injuries caused by penetrating trauma were included in the study. Demographics, vital signs on admission, Abbreviated Injury Scale per body region, Injury Severity Score, transfusion and therapeutic modality were obtained. Mortality, length of stay (LOS), pseudocyst, pancreatitis, sepsis, thromboembolism, renal failure, ARDS and unplanned ICU admission or re-operation were stratified according to injury grade and treatment modality. Patients were stratified into those who did/did not undergo pancreatic resection. ResultsA total of 4,098 patients had a pancreatic injury of which 15.9% (n=653) had a grade III and 6.7% (n=274) a grade IV pancreatic injury. There were no differences in patient demographics or overall injury severity between the resected and non-resected cohorts within each pancreatic injury grade. Forty-two percent of grade III and 38.0% of grade IV injuries underwent pancreatic resection. The total LOS was longer in the resection arm irrespective of pancreatic injury severity. There was no significant difference in morbidity between cohorts. Similarly, mortality was not significantly different between the two management approaches for grade III: 15.1% (95% CI 11.0–19.9) vs. 18.4% (95% CI 14.6–22.6), p=0.32 and grade IV: 24.0% (95% CI: 16.2–33.4) vs. 27.1% (95% CI: 20.5–34.4), p=0.68. ConclusionResection for treatment of grade III and IV pancreatic injury is not associated with a significant decrease in mortality but is associated with an increase in hospital LOS.

Isolated blunt pancreatic trauma

Blunt pancreatic trauma is rare, and the reported mortality is high. The true outcomes in isolated pancreas trauma are not known, and the optimal management according to injury severity is controversial. The present study evaluated the incidence, outcomes, and optimal management of isolated blunt pancreatic injuries. National Trauma Data Bank study, including patients with blunt pancreatic trauma. Patients with major associated injuries or other severe intra-abdominal injuries were excluded. Patients' demographics, vital signs on admission, Abbreviated Injury Scale for each body area, Injury Severity Score (ISS), and therapeutic modality were extracted. Mortality and hospital length of stay were stratified according to the severity of pancreatic injury and therapeutic modality. There were 388,137 patients with blunt abdominal trauma. Overall, 12,112 patients (3.1%) sustained pancreatic injury. Isolated pancreatic injury occurred in 2,528 (0.7%) of all abdominal injuries or 20.9% of pancreatic injuries. Most injuries were low-grade Organ Injury Scale ((OIS) score of 2, 82.7%) with only a small percentage of higher-grade injuries (OIS score of 3, 7.9%; OIS score of 4, 3.9%; and OIS score of 5, 5.5%). Overall, most patients (74.1%) were managed nonoperatively. Nonoperative management was selected in 80.5% of pancreas OIS score of 2, 48.5% of OIS score of 3, and 40.9% of OIS scores of 4 to 5. The overall mortality rate was 2.4%, while in severe pancreatic trauma it was 3.0%. In minor pancreatic trauma, nonoperative management was associated with lower mortality and shorter hospital length of stay than operative management. However, in the group of patients with severe pancreatic trauma (OIS scores, 4-5) nonoperative management was associated with higher mortality and longer hospital stay than definitive operative management of the pancreas. The mortality in isolated pancreatic trauma is low, even in severe injuries. Nonoperative management of minor pancreatic injuries is associated with lower mortality and shorter hospital stay than operative management. However, in severe trauma, nonoperative management is associated with higher mortality and longer hospital stay than operative management. Prognostic study, level III; therapeutic study, level IV.

Management of splenic and pancreatic trauma

The spleen and pancreas are at risk for injury during abdominal trauma. The spleen is more commonly injured because of its fragile structure and its position immediately beneath the ribs. Injury to the more deeply placed pancreas is classically characterized by discordance between the severity of pancreatic injury and its initial clinical expression. For the patient who presents with hemorrhagic shock and ultrasound evidence of major hemoperitoneum, urgent "damage control" laparotomy is essential; if splenic injury is the cause, prompt "hemostatic" splenectomy should be performed. Direct pancreatic injury is rarely the cause of major hemorrhage unless a major neighboring vessel is injured, but if there is destruction of the pancreatic head, a two-stage pancreatoduodenectomy (PD) may be indicated. At open laparotomy when the patient's hemodynamic status can be stabilized, it may be possible to control splenic bleeding without splenectomy; it is always essential to search for injury to the pancreatic duct and/or the adjacent duodenum. Pancreatic contusion without ductal rupture is usually treated by drain placement adjacent to the injury; ductal injuries of the pancreatic body or tail are treated by resection (distal pancreatectomy with or without splenectomy), with generally benign consequences. For injuries of the pancreatic head with pancreatic duct disruption, wide drainage is usually performed because emergency PD is a complex gesture prone to poor results. Postoperatively, the placement of a ductal stent by endoscopic retrograde catheterization may be decided, while management of an isolated pancreatic fistula is often straightforward. Non-operative management is the rule for the trauma victim who is hemodynamically stable. In addition to the clinical examination and conventional laboratory tests, investigations should include an abdominothoracic CT scan with contrast injection, allowing identification of all traumatized organs and assessment of the severity of injury. In this context, non-operative management (NOM) has gradually become the standard as long as the patient remains hemodynamically stable and there is no suspicion of injury to hollow viscera, with the patient being carefully monitored on a surgical service. The development of arteriography with splenic artery embolization has increased the rate of splenic salvage; this can be performed electively based on specific indications (blush on CT, pseudoaneurysm, arteriovenous fistula), and may also be considered for severe splenic injury, abundant hemoperitoneum, or severe polytrauma. For pancreatic injury, in addition to CT scan, magnetic resonance pancreatography (MRCP) or even endoscopic retrograde cholangiopancreatography (ERCP) may be necessary to identify a ductal rupture. If the pancreatic duct is intact, laboratory and CT imaging surveillance is performed just as for splenic injury. In case of pancreatic ductal injury, ERCP stenting can be considered. However, if this is unsuccessful, the therapeutic decision can be difficult: while NOM can still be successful, complications may arise that are difficult to treat while distal pancreatectomy, although initially more agressive may avoid these complications if performed early.

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

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

Diagnosis and Management of High-Grade Pancreatic Trauma: Report of 14 Cases.

The aim of this study was to review the diagnosis and operative management of cases of high-grade pancreatic trauma. A retrospective analysis was performed on 14 patients treated for high-grade pancreatic trauma at our institution between December 2008 and November 2013. The patients were treated for injuries resulting from blunt abdominal trauma. The main clinical data of the patients was analyzed, including time to diagnosis, initial serum amylase level, ultrasonography and abdominal computed tomography (CT) findings, pancreatic injury severity as scored according to the American Association for the Surgery of Trauma Organ Injury Scale, injury to other organs, operative treatment method, postoperative complications, and patient outcome. All 14 patients were diagnosed with severe (≥ grade III) pancreatic trauma. Diagnosis was confirmed in all seven hemodynamically stable patients that underwent CT and in 9/13 patients receiving ultrasound examination. All patients underwent surgical operations, including emergency pancreaticoduodenectomy (n = 8), splenectomy with distal pancreatectomy (n = 3), spleen-preserving distal pancreatectomy (n = 1), medial pancreatectomy with Roux-en-Y pancreaticojejunostomy (n = 1), and peripancreatic debridement and drainage (n = 1). Diagnosis was delayed beyond 24h in two patients, both of whom underwent reoperative peripancreatic debridement and drainage, with one death. The complications included pancreatic fistula (n = 8), peripancreatic abscess (n = 2), hepatic artery hemorrhage (n = 1), gastrointestinal bleeding (n = 1), and intra-abdominal abscess (n = 1). CT is the most reliable method for diagnosing high-grade pancreatic trauma. Aggressive surgical therapy including pancreaticoduodenectomy is acceptable in hemodynamically stable patients.

Trauma Pancreático Penetrante Severo-Revisión Retrospectiva de Una Serie de Casos Manejados Con Una Estrategia Simplificada en un Centro de Trauma Nivel 1.

Pancreatic trauma has a low incidence in both closed and penetrating injuries. The risk for morbidity and mortality is associated with injury severity of multiple organ injuries. To describe the characteristics of patients with penetrating pancreatic trauma treated at Foundation Valle del Lili (FVL), analyze the treatment performed and possible variables associated with the occurrence of complications related to injury to the pancreas and its treatment. A retrospective review was made. The medical records of patients with abdominal trauma penetrating with pancreatic injury seen in FVL between 2000 and 2013, and who survived more than 48 hours. We analyzed demographic variables, severity of trauma and management related to the development of pancreatic fistula. Twenty-eight patients were identified with median age 30 years (21-38). Eight (28%) were admitted in shock (SBP <90 mm Hg). The anatomical severity measured by the PATI had median 50 (34.5-67.5). The number of organs injured: a median of 5 (5-6). Twenty-one patients (75%) had major vascular injuries, 19 (68%) gastric injury, 14 (50%) colon, 12 (43%) liver, small intestine 12 and 11 (39%) duodenal. The severity of pancreatic injury was a median of 3 (2-4). Treatment of pancreatic lesion consisted of suture in 12 cases (42.8%), distal resection in 8 (28.6%) and packing in 8. Local complications occurred in 23 patients (83%), abdominal sepsis in 19 (68%), pancreatic fistula in eight (29%) and intestinal fistula in six (21%). Four patients (14%) died, two from sepsis and two from multiorgan failure. No association was found between severity of trauma or damaged organs and the risk of fistula. Only pancreatic suture was associated with lower risk of complication. We present a series of patients with penetrating pancreatic trauma with a high prevalence of serious injuries and associated morbidity, despite which mortality was reduced. Simple suture of the pancreatic injury was associated with lower risk of fistula.

Downregulation of HMGB1 protects against the development of acute lung injury after severe acute pancreatitis

ObjectiveTo examine the effect of downregulation of high mobility group box 1 (HMGB1) on severe acute pancreatitis (SAP) associated with acute lung injury (ALI), and its subsequent effect on disease severity. MethodsWistar rats were given an IV injection of pRNA-U6.1/Neo-HMGB1, pRNA-U6.1/Neo-vector or saline before induction of SAP. Then, SAP was induced in rats by the retrograde injection of 5% sodium taurocholate into the pancreatic duct. The control group received only a sham operation. Lung and pancreas samples were harvested after induction of SAP. The protein levels of HMGB1, matrix metalloproteinase-9 (MMP-9) and intercellular adhesion molecule-1 (ICAM-1) in lung tissue were investigated. The severity of pancreatic injury was determined by a histological score of pancreatic injury, serum amylase, and pancreatic water content. The lung injury was evaluated by measurement of pulmonary microvascular permeability, lung myeloperoxidase activity and malondialdehyde levels. ResultsThe results found that in pRNA-U6.1/Neo-HMGB1 treated rats, serum tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels were decreased and the severity of pancreatic tissue injury was less compared with either untreated SAP or pRNA-U6.1/Neo-vector treated rats (P<0.05). The administration of pRNA-U6.1/Neo-HMGB1 in SAP-induced rats downregulated the DNA binding activity of the nuclear factor-kappa B (NF-κB) and the expressions of MMP-9 and ICAM-1 in lung. Thus, compared with the untreated SAP rats, the inflammatory response and the severity of ALI decreased (P<0.05). ConclusionsThese results demonstrate that HMGB1 could augment Inflammation by inducing nuclear translocation of NF-κB, thus aggratating the severity of SAP associated with ALI.

Correlation of fibrinogen-like protein 2 with progression of acute pancreatitis in rats

To examine fibrinogen-like protein 2 (fgl2) expression during taurocholate-induced acute pancreatitis progression in rats and its correlation with pancreatic injury severity. Forty-eight male Sprague-Dawley rats were randomly divided into the severe acute pancreatitis (SAP) group (n = 24) and the sham operation (SO) group (n = 24). Sodium taurocholate (4% at doses of 1 mL/kg body weight) was retrogradely injected into the biliopancreatic ducts of the rats to induce SAP. Pancreatic tissues were prepared immediately after sacrifice. At the time of sacrifice, blood was obtained for determination of serum amylase activity and isolation of peripheral blood mononuclear cells (PBMCs). Pancreatic tissue specimens were obtained for routine light microscopy including hematoxylin and eosin staining, and the severity of pancreatic injury was evaluated 1, 4 and 8 h after induction. Expression of fgl2 mRNA was measured in the pancreas and PBMCs using reverse transcription polymerase chain reaction. Expression of fgl2 protein was evaluated in pancreatic tissues using Western blotting and immunohistochemical staining. Masson staining was also performed to observe microthrombosis. At each time point, levels of fgl2 mRNAs in pancreatic tissues and PBMCs were higher (P < 0.05) in the SAP group than in the SO group. For pancreatic tissue in SAP vs SO, the levels were: after 1 h, 3.911 ± 1.277 vs 1.000 ± 0.673; after 4 h, 9.850 ± 3.095 vs 1.136 ± 0.609; and after 8 h, 12.870 ± 3.046 vs 1.177 ± 0.458. For PBMCs in SAP vs SO, the levels were: after 1 h, 2.678 ± 1.509 vs 1.000 ± 0.965; after 4 h, 6.922 ± 1.984 vs 1.051 ± 0.781; and after 8 h, 13.533 ± 6.575 vs 1.306 ± 1.179. Levels of fgl2 protein expression as determined by Western blotting and immunohistochemical staining were markedly up-regulated (P < 0.001) in the SAP group compared with those in the SO group. For Western blotting in SAP vs SO, the results were: after 1 h, 2.183 ± 0.115 vs 1.110 ± 0.158; after 4 h, 2.697 ± 0.090 vs 0.947 ± 0.361; and after 8 h, 3.258 ± 0.094 vs 1.208 ± 0.082. For immunohistochemical staining in SAP vs SO, the results were: after 1 h, 1.793 ± 0.463 vs 0.808 ± 0.252; after 4 h, 4.535 ± 0.550 vs 0.871 ± 0.318; and after 8 h, 6.071 ± 0.941 vs 1.020 ± 0.406. Moreover, we observed a positive correlation in the pancreas (r = 0.852, P < 0.001) and PBMCs (r = 0.735, P < 0.001) between fgl2 expression and the severity of pancreatic injury. Masson staining showed that microthrombosis (%) in rats with SAP was increased (P < 0.001) compared with that in the SO group and it was closely correlated with fgl2 expression in the pancreas (r = 0.842, P < 0.001). For Masson staining in SAP vs SO, the results were: after 1 h, 26.880 ± 9.031 vs 8.630 ± 3.739; after 4 h, 53.750 ± 19.039 vs 8.500 ± 4.472; and after 8 h, 80.250 ± 12.915 vs 10.630 ± 7.003. Microthrombosis due to fgl2 overexpression contributes to pancreatic impairment in rats with SAP, and fgl2 level may serve as a biomarker during early stages of disease.

Clinico-Pathological Particularities of the Shock-Related Pancreatitis

Acute pancreatitis can develop in patients with shock due to the underlying diseases, surgical interventions or because of severe hypoperfusion. The aim of our work was to study the histological alterations of the pancreas in patients dying after cardiogenic, hypovolemic or septic shock, to demonstrate the presence and severity of pancreatic injury. We performed a retrospective study which included patients who died and who were autopsied after different types of shock, hospitalized between 2007-2009 in general and cardiac intensive care units. We excluded the patients with known pancreatic diseases. From 223 patients included in our study 39 presented necrotising hemorrhagic alteration of the pancreatic tissue. There were no differences in histological and immunohistochemical findings between the different etiopathogenetic types of shock. None of the patients had characteristic clinical signs for acute pancreatitis. The digestive symptoms, they presented, could be related to the underlying disease or to postoperative state. The common findings in these patients were prolonged and severe hypotension, associated renal dysfunction, leucocytosis, hyperglycemia and hypocalcemia. Pancreatitis can occur in patients with shock, due to prolonged hypoperfusion of the pancreas. It is difficult to diagnose it because clinical signs are altered due to severity of underlying disease or analgo-sedation commonly used in intensive care. We therefore recommend in patients with shock to consider the possible development of ischemic pancreatitis for prompt and efficient treatment.

Upregulation of PIAS1 protects against sodium taurocholate-induced severe acute pancreatitis associated with acute lung injury

The regulator of cytokine signaling known as protein inhibitor of activated STAT-1 (PIAS1) is increasingly understood to have diverse regulatory functions for inflammation, but its effect in inflammatory conditions such as severe acute pancreatitis (SAP) has not previously been reported. The aim of this study was to investigate the effect of upregulation of PIAS1 on SAP associated with acute lung injury (ALI), and its subsequent effect on disease severity. Sprague–Dawley rats were given an IV injection of adenovirus serotype 5 (Ad5)/F35-PIAS1, Ad5/F35-vector or saline before induction of SAP. The control group received only a sham operation. Lung and pancreas samples were harvested 16 h after induction. The protein levels of PIAS1 in tissue were investigated. The severity of pancreatic injury was determined by a histological score of pancreatic injury, serum amylase, and pancreatic water content. The lung injury was evaluated by measurement of pulmonary microvascular permeability, lung myeloperoxidase activity and malondialdehyde levels. The survival rates of rats were also analyzed. The results found that in Ad5/F35-PIAS1 treated rats, serum tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 levels were decreased but showed no influence on the levels of IL-10, and the severity of pancreatic tissue injury was less compared with either untreated SAP or Ad5/F35-vector treated rats ( P < 0.01). The administration of Ad5/F35-PIAS1 in SAP-induced rats downregulated the activity of the signal transducer and activator of transcription-1 (STAT1) pathway and the expressions of matrix metalloproteinase-9 (MMP-9) and intercellular adhesion molecule (ICAM)-1 protein in lung. Thus, compared with the untreated SAP rats, the inflammatory response and the severity of ALI decreased, and the survival rates increased ( P < 0.01). These findings suggest that PIAS1 could augment anti-inflammatory activity by inhibiting STAT1, thus attenuating the severity of SAP associated with ALI.

Probiotics enhance pancreatic glutathione biosynthesis and reduce oxidative stress in experimental acute pancreatitis

Factors determining severity of acute pancreatitis (AP) are poorly understood. Oxidative stress causes acinar cell injury and contributes to the severity, whereas prophylactic probiotics ameliorate experimental pancreatitis. Our objective was to study how probiotics affect oxidative stress, inflammation, and acinar cell injury during the early phase of AP. Fifty-three male Sprague-Dawley rats were randomly allocated into groups: 1) control, 2) sham procedure, 3) AP with no treatment, 4) AP with probiotics, and 5) AP with placebo. AP was induced under general anesthesia by intraductal glycodeoxycholate infusion (15 mM) and intravenous cerulein (5 microg.kg(-1).h(-1), for 6 h). Daily probiotics or placebo were administered intragastrically, starting 5 days prior to AP. After cerulein infusion, pancreas samples were collected for analysis including lipid peroxidation, glutathione, glutamate-cysteine-ligase activity, histological grading of pancreatic injury, and NF-kappaB activation. The severity of pancreatic injury correlated to oxidative damage (r = 0.9) and was ameliorated by probiotics (1.5 vs. placebo 5.5; P = 0.014). AP-induced NF-kappaB activation was reduced by probiotics (0.20 vs. placebo 0.53 OD(450nm)/mg nuclear protein; P < 0.001). Probiotics attenuated AP-induced lipid peroxidation (0.25 vs. placebo 0.51 pmol malondialdehyde/mg protein; P < 0.001). Not only was AP-induced glutathione depletion prevented (8.81 vs. placebo 4.1 micromol/mg protein, P < 0.001), probiotic pretreatment even increased glutathione compared with sham rats (8.81 vs. sham 6.18 miccromol/mg protein, P < 0.001). Biosynthesis of glutathione (glutamate-cysteine-ligase activity) was enhanced in probiotic-pretreated animals. Probiotics enhanced the biosynthesis of glutathione, which may have reduced activation of inflammation and acinar cell injury and ameliorated experimental AP, via a reduction in oxidative stress.

Protease-activated Receptor-2 Exerts Contrasting Model-specific Effects on Acute Experimental Pancreatitis

Protease-activated receptor-2 (PAR2) is a 7-transmembrane G-protein-coupled tethered ligand receptor that is expressed by pancreatic acinar and ductal cells. It can be physiologically activated by trypsin. Previously reported studies (Namkung, W., Han, W., Luo, X., Muallem, S., Cho, K. H., Kim, K. H., and Lee, M. G. (2004) Gastroenterology 126, 1844-1859; Sharma, A., Tao, X., Gopal, A., Ligon, B., Andrade-Gordon, P., Steer, M. L., and Perides, G. (2005) Am. J. Physiol. 288, G388-G395) have shown that PAR2 activation exerts a protective effect on the experimental model of pancreatitis induced by supramaximal secretagogue (caerulein) stimulation. We now show that PAR2 exerts a worsening effect on a different model of experimental pancreatitis, i.e. one induced by retrograde pancreatic ductal infusion of bile salts. In vitro studies using freshly prepared pancreatic acini show that genetic deletion of PAR2 reduces bile salt-induced pathological calcium transients, acinar cell injury, and activation of c-Jun N-terminal kinase, whereas genetic deletion of PAR2 has the opposite or no effect on these pancreatitis-related events when they are elicited, in vitro, by caerulein stimulation. Studies employing a combination of trypsin inhibition and activation of PAR2 with the activating peptide SLIGRL show that all these differences indeed depend on the activation of PAR2. These studies are the first to report that a single perturbation can have model-specific and opposite effects on pancreatitis, and they underscore the importance of performing mechanistic pancreatitis studies using two dissimilar models of the disease to detect idiosyncratic, model-specific events. We suggest PAR2 activation exerts a worsening effect on the severity of clinical pancreatitis and that interventions interfering with PAR2 activation may be of benefit in the treatment of patients with severe pancreatitis.

Severity of post-ERCP pancreatitis directly proportional to the invasiveness of endoscopic intervention: a pilot study in a canine model

Pancreatitis complicates 1% - 22% of endoscopic retrograde cholangiopancreatography procedures. The study aims were to develop a reproducible animal model of post-ERCP pancreatitis (PEP), and investigate the impact of endoscopic technique on severity of PEP. ERCP was carried out in six male hound dogs. Pancreatitis was induced by one of three escalating methods: 1) pancreatic acinarization with 20 - 30 mL of contrast; 2) acinarization + ductal balloon occlusion + sphincterotomy; 3) acinarization + intraductal synthetic bile injection + ductal balloon occlusion + sphincterotomy. Dogs 5 and 6 received a pancreatic stent. Necropsy was performed on postoperative day 5. All pancreatic specimens were graded by two blinded pathologists according to a validated scoring system. All dogs were compared with three control dogs. Dogs 1 - 4 developed clinical pancreatitis and hyperamylasemia (11 736 vs. 722 U/L, P = 0.02). Total injury scores were significantly elevated compared with controls (6.85 vs. 1.06, P = 0.004). There was significant increase in acinar cell necrosis (0.86 vs. 0.06, P = < 0.001), and all other categories (except fibrosis) demonstrated elevated injury scores . Dogs 5 and 6 developed clinical pancreatitis without significant hyperamylasemia; total injury scores were elevated compared with controls (4.83 vs. 1.06, P = 0.01), but lower than in Dogs 1 - 4 (4.83 vs. 6.85, P = 0.25). There was escalating severity of pancreatic injury from Dogs 1 to 4 correlating with the method of endoscopic injury used. Severity of PEP is directly proportional to invasiveness of endoscopic intervention. Pancreatic acinarization, even without balloon occlusion and sphincterotomy, can be used as a reliable animal model for future studies investigating therapy and prevention of disease.

Effects of N-acetylcysteine on mRNA expression of monocyte chemotactic protein and macrophage inflammatory protein 2 in acute necrotizing pancreatitis: experiment with rats

To explore the potential role of monocyte chemotactic protein 1 (MCP-1) and macrophage inflammatory protein 2 (MIP-2) in the pathogenesis of acute necrotizing pancreatitis (ANP), and to study the effect of N-acetylcysteine (NAC) on the mRNA expression of MCP-1 and MIP-2. Thirty-five SD rats were randomly divided into 3 groups: sham-operation (SO) group (n = 5), acute necrotizing pancreatitis (ANP) group (n = 15), and NAC-pretreated group (n = 15), ANP were induced by retrograde injection of 4% sodium taurocholate into the biliopancreatic duct. The NAC- groups underwent intraperitoneal injection of NAC 500 mg/kg 30 minutes before the induction of sodium taurocholate. The ANP and NAC groups were re-divided into 3 equal subgroups respectively: 3 h, 6 h, and 12 h subgroups. 3, 6, and 12 hours after the establishment of models heart blood samples were collected from 5 rats from each model group to detect the serum amylase. Then the rats were killed by blood letting with their pancreases taken out. HE staining and microscopy were used to observe the pathological changes of the pancreas. The wet/dry ratio of pancreas was determined. Enzyme histochemical method was used to detect the activity of myeloperoxidase (MPO) in the pancreas. RT-PCR was used to examine the mRNA expression of MCP-1 and MIP-2. The levels of serum amylase, wet/dry ratio of pancreas, pancreatic MPO activity, and histological score of pancreas of the ANP group increased time-dependently, all the levels at different time-points were significantly higher than those of the SO group (all P < 0.01). The expression levels of MCP-1 mRNA at the time points 3, 6, and 12 h of the ANP group were 0.3653 +/- 0.0213, 0.5890 +/- 0.0225, and 0.7164 +/- 0.0275 respectively, all significantly higher than that of the SO group (0.1492 +/- 0.0036, all P < 0.01). The expression levels of MIP-2 mRNA at different time points of the ANP group were 0.3871 +/- 0.0286, 0.6040 +/- 0.0448, and 0.7692 +/- 0.0620 respectively, all significantly higher than that of the SO group (0.1593 +/- 0.0117, all P < 0.01). The intrapancreatic MPO levels at the time points 3 h, 6 h, and 12 h of the NAC group were 0.63 +/- 0.03, 0.88 +/- 0.05, and 1.31 +/- 0.09 respectively, all significantly lower than those of the ANP groups (0.89 +/- 0.03, 1.42 +/- 0.14, and 1.94 +/- 0.07, all P < 0.05). The MCP-1 mRNA expression levels at different time points the NAC group were 0.2497 +/- 0.0168, 0.4457 +/- 0.0097, and 0.6306 +/- 0.0423 respectively, and the MIP-2 mRNA expression levels at the time points 3 h, 6 h, and 12 h of the NAC group were 0.2436 +/- 0.0099, 0.4312 +/- 0.0221, and 0.6302 +/- 0.0288 respectively, all significantly lower than those of the ANP group (all P < 0.05). The pancreatic histological scores at different time points of the NAC group were 3.50 +/- 0.61, 5.60 +/- 0.65, and 7.50 +/- 0.79, all significantly lower than those of the ANP group (5.10 +/- 0.42, 7.50 +/- 0.50, and 9.90 +/- 0.96, all P < 0.05). The MCP-1 mRNA expression and MIP-2 mRNA expression were both correlated with the severity of pancreatic injury (r = 0.76 and 0.82, both P < 0.05). The chemokines of MCP-1 and MIP-2 are overexpressed at the early stage of acute pancreatitis. Both of them may play an important role in the pathogenesis of AP. NAC may have beneficial effects on AP through downregulation of the expression of MCP-1 and MIP-2.

Prognostic Determinants in Patients with Traumatic Pancreatic Injuries

The aim of this study was to identify factors that predict morbidity and mortality in patients with traumatic pancreatic injuries. A retrospective review was performed on 75 consecutive patients with traumatic pancreatic injuries admitted to the Emergency Medical Center at Masan Samsung Hospital and subsequently underwent laparotomy during the period January 2000 to December 2005. Overall mortality and morbidity rates were 13.3% and 49.3%, respectively. A multivariate regression analysis revealed that greater than 12 blood transfusions and an initial base deficit of less than -11 mM/L were the most important predictors of mortality (p<0.05). On the other hand, the most important predictors of morbidity were surgical complexity and an initial base deficit of less than -5.8 mM/L (p<0.01). These data suggests that early efforts to prevent shock and rapidly control of bleeding are most likely to improve the outcome in patients with traumatic pancreatic injuries. The severity of pancreatic injury per se influenced only morbidity.

The Therapeutic Effect of Oxidized 1-Palmitoyl-2-Arachidonoyl-sn-Glycero-3-Phosphorylcholine in Rodents With Acute Necrotizing Pancreatitis and Its Mechanism

This study aims to investigate the therapeutic effect of oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (OXPAPC) in rodents with acute necrotizing pancreatitis (ANP) and its mechanism. The ANP model was induced by cerulein challenged by lipopolysaccharide in mice and taurocholic acid in Sprague-Dawley rats. Both ANP models were treated with OXPAPC. Twenty animals of each group were separated to investigate mortality. Detection included serum levels of amylase and lactate dehydrogenase, histological changes of pancreas, activity of myeloperoxidase in pancreas, mRNA expression of inflammatory factors, expression of signal transduction factor proteins, and binding activity of transcriptional factors. After treatment with OXPAPC, survival rate was improved in the rat model. In both models, OXPAPC significantly decreased serum amylase and lactate dehydrogenase levels. Histologically, OXPAPC reduced the severity of pancreatic injury. There was a significant decline of myeloperoxidase activity. The mRNA levels of intrapancreatic inflammatory factors were depressed. Activated p38, C-jun N-terminal kinase 1, and inhibitor of kappa-B kinase beta proteins were down-regulated. Electrophoretic mobility shift assay showed that the binding activity of nuclear factor-kappaB and activator protein 1 to DNA was inhibited. The OXPAPC decreased the severity of experimental ANP in rodents. The protective effect of OXPAPC was mediated, at least in part, through blocking the lipopolysaccharide signal pathway.

Enterokinase induces severe necrosis and rapid mortality in cerulein pancreatitis: Characterization of a novel noninvasive rat model of necro-hemorrhagic pancreatitis

Unlike edematous pancreatitis, induction of severe necrotizing pancreatitis in rats generally requires an invasive laparotomy with infusion and/or ligation of the pancreatic duct or duodenal or arterial occlusion. The aim of this study was to establish and characterize a noninvasive model of severe acute pancreatitis in rats. Wistar rats were infused intravenously with cerulein or a combination of cerulein and enterokinase. Saline (154-mmol/L NaCl) or enterokinase only was infused in controls. In a first set of experiments, intrapancreatic protease activation and the release of cytokines were correlated with the severity of organ injury. Pancreatic and pulmonary injuries were determined at 6 h. In a second set of experiments, we assessed 24-h survival, serum parameters possibly reflecting the course of the disease, and morphologic changes later in the course of the disease. The severity of pancreatic injury and survival were correlated strongly with the amount of enterokinase infused simultaneously with cerulein. Trypsin as well as elastase and cathepsin B activity in pancreatic tissue samples were increased markedly in these animals. Marked pancreatic hemorrhage, necrosis, and leukocyte infiltration were present in animals with the greatest amounts of enterokinase infused. IL-6 and LDH, but not IL-1beta, CRP, and amylase, in serum correlated with the severity of pancreatitis. This noninvasive rat model of acute pancreatitis is characterized by major pancreatic necrosis, hemorrhage, and fatality. The simple and noninvasive induction technique may have advantages for future studies on inflammatory changes and sepsis in necrotizing pancreatitis compared with other currently available invasive models.