Pancreatic Duct Ligation Research Articles

Pharmacological Inhibition of Phosphoglycerate Kinase 1 Reduces OxiDative Stress and Restores Impaired Autophagy in Experimental Acute Pancreatitis.

Damage to pancreatic acinar cells (PAC) and intracellular metabolic disturbances play crucial roles in pancreatic necrosis during acute pancreatitis (AP). Phosphoglycerate kinase 1 (PGK1) is a crucial catalytic enzyme in glycolysis. However, the impact of PGK1-involving glycolysis in regulating metabolic necrosis in AP is unclear. Transcriptome analysis of pancreatic tissues revealed significant changes in the glycolysis pathway and PGK1 which positively correlated with the inflammatory response and oxidative stress injury in AP mice. Furthermore, we observed a substantial increase in PGK1 expression in damaged PAC, positively correlating with PAC necrosis. Treatment with NG52, a specific PGK1 inhibitor, ameliorated pancreatic necrosis, inflammatory damage, and oxidative stress. Transcriptomic data before and after NG52 treatment along with the Programmed Cell Death database confirmed that NG52 protected against PAC damage by rescuing impaired autophagy in AP. Additionally, the protective effect of NG52 was validated following pancreatic duct ligation. These findings underscore the involvement of PGK1 in AP pathogenesis, highlighting that PGK1 inhibition can mitigate AP-induced pancreatic necrosis, attenuate inflammatory and oxidative stress injury, and rescue impaired autophagy. Thus, the study findings suggest a promising interventional target for pancreatic necrosis, offering novel strategies for therapeutic approaches to clinical AP.

Pancreas-directed AAV8-hSPINK1 gene therapy safely and effectively protects against pancreatitis in mice

ObjectiveCurrently, there is no cure for chronic pancreatitis (CP). Germline loss-of-function variants in SPINK1 (encoding trypsin inhibitor) are common in patients with CP and are associated with acute attacks and...

Hspb1 protects against severe acute pancreatitis by attenuating apoptosis and ferroptosis via interacting with Anxa2 to restore the antioxidative activity of Prdx1.

Acute pancreatitis (AP) is a common abdominal disease that typically resolves on its own, but the mortality rate dramatically increases when it progresses to severe acute pancreatitis (SAP). In this study, we investigated the molecular mechanism underlying the development of SAP from AP. We utilized two SAP models induced by pancreatic duct ligation and caerulein administration. Transcriptomic and proteomic analyses were subsequently performed to determine the mRNA and protein expression profiles of pancreatic samples from SAP and AP model and normal mice. To explore the role of Hspb1 in SAP, we used Hspb1 knockout (KO) mice, a genetically engineered chronic pancreatitis strain (T7D23A), Anxa2 KO mice, and acinar cell-specific Prdx1 knockout mice. Additionally, various in vivo and in vitro assays were performed to elucidate the molecular events and direct targets of Hspb1 in acinar cells. We found that Hspb1 expression was upregulated in AP samples but significantly reduced in acinar cells from SAP samples. KO or inhibition of Hspb1 worsened AP, while AAV8-Hspb1 administration mitigated the severity of SAP and reduced remote organ damage in mice. Furthermore, AAV8-Hspb1 treatment prevented the development of chronic pancreatitis. We found that KO or inhibition of Hspb1 promoted acinar cell death through apoptosis and ferroptosis but not necroptosis or autophagy by increasing reactive oxygen species (ROS) and lipid ROS levels. Mechanistically, Hspb1 directly interacted with Anxa2 to decrease its aggregation and phosphorylation, interact with the crucial antioxidant enzyme Prdx1, and maintain its antioxidative activity by decreasing Thr-90 phosphorylation. Notably, the overexpression of Hspb1 did not have a protective effect on acinar-specific Prdx1 knockout mice. In summary, our findings shed light on the role of Hspb1 in acinar cells. We showed that targeting Hspb1/Anxa2/Prdx1 could serve as a potential therapeutic strategy for SAP.

Anti-Incretin Gut Features Induced by Feed Supplementation with Alpha-Amylase: Studies on EPI Pigs.

The acini-islet-acinar (AIA) axis concept justifies the anatomical placement of the Langerhans islets within the exocrine pancreatic parenchyma and explains the existence of the pancreas as a single organ. Amylase has been suggested to play a key role as an anti-incretin factor. Oral glucose tolerance tests (OGTT) were performed on 18 piglets in both a healthy (prior to pancreatic duct ligation (PDL) surgery, study Day 10) and an exocrine pancreatic insufficient (EPI) state (30 days after PDL, study Day 48)). Amylase (4000 units/feeding) or Creon® (100,000 units/feeding) was administered to pigs with the morning and evening meals, according to study design randomization, for 37 days following the first OGTT. Blood glucose levels, as well as plasma levels of insulin, GLP-1, and GIP, were measured, and the HOMA-IR index was calculated. EPI status did not affect the area under the curve (AUC) of insulin release, fasting insulin levels, or the HOMA-IR index, while amylase supplementation led to a significant (p < 0.05) decrease in the above-mentioned parameters. At the same time, EPI led to a significant (p < 0.05) increase in GLP-1 levels, and neither amylase nor Creon® supplementation had any effects on this EPI-related increase. Fasting plasma levels of GIP were not affected by EPI; however, the GIP response in EPI and Amylase-treated EPI animals was significantly lower (p < 0.05) when compared to that of the intact, healthy pigs. Orally administered amylase induces gut anti-incretin action, normalizing glucose homeostasis and reducing HOMA-IR as a long-term outcome, thus lowering the risk of diabetes type II development. Amylase has long-lasting anti-incretin effects, and one could consider the existence of a long-lasting gut memory for amylase, which decreases hyperinsulinemia and hyperglycemia for up to 16 h after the last exposure of the gut to amylase.

Effect of main pancreatic duct suture ligation on the prevention of clinically relevant pancreatic fistula after distal pancreatectomy: analysis of 82 consecutive patients.

This study aimed to examine the factors linked to the development of clinically significant pancreatic fistulas following distal pancreatectomy (DP) and to assess the efficacy of suture ligation of the main pancreatic duct. A single-center retrospective study was performed on the medical records of 82 patients who underwent DP in our institution between January 2011 and December 2019. There were 28 males (34.1%) and 54 females (65.9%). The patients' age ranged from 18 to 86 years (median: 55.5 years). Indications for DP included primary pancreatic disease (n=63, 76.8%) and non-pancreatic disease (n=19, 23.2%). Postoperative mortality and morbidity rates were 3.7% and 48%, respectively. Pancreatic parenchymal closure was accomplished by a hand-sewn technique or mechanical stapling in 89 and 13 patients, respectively. Identification of the pancreatic duct and suture ligation was performed in 46 patients (56.1%). Pancreatic fistula was developed in 20 patients (24.4%); 12 fistulas were classified as Grade B, and 8 as Grade C. Biochemical leaks (Grade A) were identified in 8 patients (9.8%). Multivariate analysis indicated that failure to ligate the main pancreatic duct was the only variable associated with an increased risk for pancreatic leak (p=0.031; odds ratio=0.233; 95% confidence interval, 0.062-0.879). Pancreatic leak remains a common complication after DP. The incidence of leaks is reduced significantly when the main pancreatic duct is identified and directly ligated during DP.

Pancreatic Acinar Cells-Derived Sphingosine-1-Phosphate Contributes to Fibrosis of Chronic Pancreatitis via Inducing Autophagy and Activation of Pancreatic Stellate Cells

Studies have demonstrated that activated pancreatic stellate cells (PSCs) play a crucial role in pancreatic fibrogenesis in chronic pancreatitis (CP); however, the precise mechanism for PSCs activation has not been fully elucidated. We analyzed the role of injured pancreatic acinar cells (iPACs) in the activation of PSCs of CP. Sphingosine kinase 1 (SPHK1)/sphingosine-1-phosphate (S1P) signaling was evaluated in experimental CP induced by cerulein injection or pancreatic duct ligation,as well as in PACs injured by cholecystokinin. The activation of PSCs and pancreatic fibrosis in CP samples was evaluated by immunohistochemical and immunofluorescence analyses. Invitro coculture assay of iPACs and PSCs was created to evaluate the effect of the SPHK1/S1P pathway and S1P receptor 2 (SIPR2) on autophagy and activation of PSCs. The pathogenesis of CP was assessed in SPHK1-/- mice or PACs-specific SPHK1-knockdown mice with recombinant adeno-associated virus serotypes 9-SPHK1-knockdown, as well as in mice treated with inhibitor of SPHK1 and S1P receptor 2 (S1PR2). SPHK1/S1P was remarkably increased in iPACs and acinar cells in pancreatic tissues of CP mice. Meanwhile, the pathogenesis, fibrosis, and PSCs activation of CP was significantly prevented in SPHK1-/- mice and recombinant adeno-associated virus serotypes 9-SPHK1-knockdown mice. Meanwhile, iPACs obviously activated PSCs, which was prevented by SPHK1 knockdown in iPACs. Moreover, iPACs-derived S1P specifically combined to S1PR2 of PSCs, by which modulated 5' adenosine monophosphate-activated protein kinase/mechanistic target of rapamycin pathway and consequently induced autophagy and activation of PSCs.Furthermore, hypoxia-inducible factor 1-α and -2α promoted SPHK1 transcription of PACs under hypoxia conditions, which is a distinct characteristic of the CP microenvironment. Coincidently, inhibition of SPHK1 and S1PR2 activity with inhibitor PF-543 and JTE-013 obviously impeded pancreatic fibrogenesis of CP mice. The activated SPHK1/S1P pathway in iPACs induces autophagy and activation of PSCs by regulating the S1PR2/5' adenosine monophosphate-activated protein kinase/mammalian target of rapamycin pathway, which promotes fibrogenesis of CP. The hypoxia microenvironment might contribute to the cross talk between PACs and PSCs in pathogenesis of CP.

IRAK3-mediated suppression of pro-inflammatory MyD88/IRAK signaling affects disease severity in acute pancreatitis

Acute pancreatitis (AP), which is characterized by self-digestion of the pancreas by its own prematurely activated digestive proteases, is a major reason for hospitalization. The autodigestive process causes necrotic cell death of pancreatic acinar cells and the release of damage associated molecular pattern which activate macrophages and drive the secretion of pro-inflammatory cytokines. The MYD88/IRAK signaling pathway plays an important role for the induction of inflammatory responses. Interleukin-1 receptor associated kinase-3 (IRAK3) is a counter-regulator of this pathway. In this study, we investigated the role of MYD88/IRAK using Irak3−/− mice in two experimental animal models of mild and severe AP. IRAK3 is expressed in macrophages as well as pancreatic acinar cells where it restrains NFκB activation. Deletion of IRAK3 enhanced the migration of CCR2+ monocytes into the pancreas and triggered a pro-inflammatory type 1 immune response characterized by significantly increased serum levels of TNFα, IL-6, and IL-12p70. Unexpectedly, in a mild AP model this enhanced pro-inflammatory response resulted in decreased pancreatic damage, whereas in a severe AP model, induced by partial pancreatic duct ligation, the increased pro-inflammatory response drives a severe systemic inflammatory response syndrome (SIRS) and is associated with an increased local and systemic damage. Our results indicate that complex immune regulation mechanism control the course of AP, where moderate pro-inflammation not necessarily associates with increased disease severity but also drives tissue regenerative processes through a more effective clearance of necrotic acinar cells. Only when the pro-inflammation exceeds a certain systemic level, it fuels SIRS and increases disease severity.

Bone-marrow derived cells do not contribute to new beta-cells in the inflamed pancreas.

The contribution of bone-marrow derived cells (BMCs) to a newly formed beta-cell population in adults is controversial. Previous studies have only used models of bone marrow transplantation from sex-mismatched donors (or other models of genetic labeling) into recipient animals that had undergone irradiation. This approach suffers from the significant shortcoming of the off-target effects of irradiation. Partial pancreatic duct ligation (PDL) is a mouse model of acute pancreatitis with a modest increase in beta-cell number. However, the possibility that recruited BMCs in the inflamed pancreas may convert into beta-cells has not been examined. Here, we used an irradiation-free model to track the fate of the BMCs from the donor mice. A ROSA-mTmG red fluorescent mouse was surgically joined to an INS1Cre knock-in mouse by parabiosis to establish a mixed circulation. PDL was then performed in the INS1Cre mice 2 weeks after parabiosis, which was one week after establishment of the stable blood chimera. The contribution of red cells from ROSA-mTmG mice to beta-cells in INS1Cre mouse was evaluated based on red fluorescence, while cell fusion was evaluated by the presence of green fluorescence in beta-cells. We did not detect any red or green insulin+ cells in the INS1Cre mice, suggesting that there was no contribution of BMCs to the newly formed beta-cells, either by direct differentiation, or by cell fusion. Thus, the contribution of BMCs to beta-cells in the inflamed pancreas should be minimal, if any.

Use of a dual genetic system to decipher exocrine cell fate conversions in the adult pancreas

Unraveling cell fate plasticity during tissue homeostasis and repair can reveal actionable insights for stem cell biology and regenerative medicine. In the pancreas, it remains controversial whether lineage transdifferentiation among the exocrine cells occur under pathophysiological conditions. Here, to address this question, we used a dual recombinase-mediated genetic system that enables simultaneous tracing of pancreatic acinar and ductal cells using two distinct genetic reporters, avoiding the “ectopic” labeling by Cre-loxP recombination system. We found that acinar-to-ductal transdifferentiation occurs after pancreatic duct ligation or during caerulein-induced pancreatitis, but not during homeostasis or after partial pancreatectomy. On the other hand, pancreatic ductal cells contribute to new acinar cells after significant acinar cell loss. By genetic tracing of cell proliferation, we also quantify the cell proliferation dynamics and deduce the turnover rate of pancreatic exocrine lineages during homeostasis. Together, these results suggest that the lineage transdifferentiation happens between acinar cells and ductal cells in the pancreatic exocrine glands under specific conditions.

Systemic Bile Acids Affect the Severity of Acute Pancreatitis in Mice Depending on Their Hydrophobicity and the Disease Pathogenesis.

Acute pancreatitis (AP) is a major, globally increasing gastrointestinal disease and a biliary origin is the most common cause. However, the effects of bile acids (BAs), given systemically, on the pancreas and on disease severity remains elusive. In this study, we have investigated the roles of different circulating BAs in animal models for AP to elucidate their impact on disease severity and the underlying pathomechanisms. BAs were incubated on isolated acini and AP was induced through repetitive injections of caerulein or L-arginine; pancreatic duct ligation (PDL); or combined biliopancreatic duct ligation (BPDL). Disease severity was assessed using biochemical and histological parameters. Serum cholecystokinin (CCK) concentrations were determined via enzyme immunoassay. The binding of the CCK1 receptor was measured using fluorescence-labeled CCK. In isolated acini, hydrophobic BAs mitigated the damaging effects of CCK. The same BAs further enhanced pancreatitis in L-arginine- and PDL-based pancreatitis, whereas they ameliorated pancreatic damage in the caerulein and BPDL models. Mechanistically, the binding affinity of the CCK1 receptor was significantly reduced by hydrophobic BAs. The hydrophobicity of BAs and the involvement of CCK seem to be relevant in the course of AP. Systemic BAs may affect the severity of AP by interfering with the CCK1 receptor.

Influences of exocrine pancreatic insufficiency on nutrient digestibility, growth parameters as well as anatomical and histological morphology of the intestine in a juvenile pig model.

In a pig model, pancreatic duct ligation (PL) leads to a complete loss of exocrine function, causing an exocrine pancreatic insufficiency (EPI) without affecting endocrine function, allowing research of clinical effects and therapy options. This study aimed to investigate effects of experimentally induced EPI in juvenile pigs on digestion and intestinal morphology. Eight female juvenile cross-bred pigs (BW 54.8 kg at the start of the study) were included. Three animals were considered as a control (CON group), and in five animals the ductus pancreaticus accessorius was ligated (PL group). During the 10-week trial period, body weight and body measurements were recorded regularly. At the end of the trial, gastrointestinal tract (GIT) was investigated macroscopically and histologically and weight and digesta samples of individual segments were obtained. The pigs in the CON showed a significantly higher apparent total tract digestibility of crude protein and crude fat (87.8 and 79.9%, respectively) compared to PL (52.4 and 16.6%, respectively). Significant differences were noted in relative weights of duodenum, jejunum and colon (with and without digesta) and also in absolute weights of jejunum and colon. The mean number of nuclei in the transverse section in stratum circulare were significantly higher in all intestinal segments in CON compared to PL. Overall, EPI results in impaired nutrient digestibility with a greater filling of the GIT with digesta. The elongation of the small intestine does not represent “stretching” of the intestine, but rather increased synthesis of intestinal tissue.

Postoperative morbidity and mortality after pancreatoduodenectomy with pancreatic duct occlusion compared to pancreatic anastomosis: a systematic review and meta-analysis.

Pancreatoduodenectomy is burdened by elevated postoperative morbidity. Pancreatic duct ligation or occlusion have been experimented as an alternative to reduce the insurgence of postoperative pancreatic fistula. The aim of this systematic review and meta-analysis was to compare postoperative mortality and morbidity (pancreatic fistula, postoperative hemorrhage, delayed gastric emptying, pancreatic exocrine insufficiency and diabetes mellitus) between patients undergoing pancreatic anastomosis or pancreatic duct ligation/occlusion after pancreatoduodenectomy. A systematic review and meta-analysis of 13 studies was conducted following the PRISMA guidelines and the Cochrane protocol (PROSPERO ID: CRD42021249232). No difference in postoperative mortality was highlighted. Pancreatic anastomosis was found to be protective considering all-grades pancreatic fistula (RR: 2.38, p=0.0005), but pancreatic duct occlusion presented a 3-folded reduced risk to develop "grade C" pancreatic fistula (RR: 0.36, p=0.1186), although not significant. Diabetes mellitus was more often diagnosed after duct occlusion (RR: 1.61, p<0.0001); no difference was found in terms of pancreatic exocrine insufficiency (RR: 1.19, p=0.151). Postoperative mortality is not influenced by the pancreatic reconstruction technique. Pancreatic anastomosis is associated with a reduction in all-grades pancreatic fistula. More high-quality studies are needed to clarify if duct sealing could reduce the prevalence of "grade C" fistula.

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

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

IL11 Activates Pancreatic Stellate Cells and Causes Pancreatic Inflammation, Fibrosis and Atrophy in a Mouse Model of Pancreatitis.

Interleukin-11 (IL11) is important for fibrosis and inflammation, but its role in the pancreas is unclear. In pancreatitis, fibrosis, inflammation and organ dysfunction are associated with pancreatic stellate cell (PSC)-to-myofibroblast transformation. Here, we show that IL11 stimulation of PSCs, which specifically express IL11RA in the pancreas, results in transient STAT3 phosphorylation, sustained ERK activation and PSC activation. In contrast, IL6 stimulation of PSCs caused sustained STAT3 phosphorylation but did not result in ERK activation or PSC transformation. Pancreatitis factors, including TGFβ, CTGF and PDGF, induced IL11 secretion from PSCs and a neutralising IL11RA antibody prevented PSC activation by these stimuli. This revealed an important ERK-dependent role for autocrine IL11 activity in PSCs. In mice, IL11 was increased in the pancreas after pancreatic duct ligation, and in humans, IL11 and IL11RA levels were elevated in chronic pancreatitis. Following pancreatic duct ligation, administration of anti-IL11RA to mice reduced pathologic (ERK, STAT, NF-κB) signalling, pancreatic atrophy, fibrosis and pro-inflammatory cytokine (TNFα, IL6 and IL1β) levels. This is the first description of IL11-mediated activation of PSCs, and the data suggest IL11 as a stromal therapeutic target in pancreatitis.

Role of angiogenesis in beta-cell epithelial–mesenchymal transition in chronic pancreatitis-induced diabetes

AbstractClinical evidence suggests that patients with chronic pancreatitis (CP) are prone to development of diabetes (chronic pancreatitis-related diabetes; CPRD), whereas the underlying mechanisms are not fully determined. Recently, we showed that the gradual loss of functional beta-cells in a mouse model for CPRD, partial pancreatic duct ligation (PDL), results from a transforming growth factor β1 (TGFβ1)-triggered beta-cell epithelial–mesenchymal transition (EMT), rather than from apoptotic beta-cell death. Here, the role of angiogenesis in CPRD-associated beta-cell EMT was addressed. We detected enhanced angiogenesis in the inflamed pancreas from CP patients by bioinformatic analysis and from PDL-mice. Inhibition of angiogenesis by specific antisera for vascular endothelial growth factor receptor 2 (VEGFR2), DC101, did not alter the loss of beta-cells and the fibrotic process in PDL-pancreas. However, DC101-mediated inhibition of angiogenesis abolished pancreatitis-induced beta-cell EMT and rendered it to apoptotic beta-cell death. Thus, our data suggest that angiogenesis promotes beta-cell survival in the inflamed pancreas, while suppression of angiogenesis turns beta-cell EMT into apoptotic beta-cell death. This finding could be informative during development of intervention therapies for CPRD.

Therapeutic Methylprednisolone and Infimab Decrease the Severity of Organ Dysfunction in Pancreatic Duct Ligation Model of Severe Acute Pancreatitis in Wistar Rats

Introduction: There is no standardized, widely used model of severe acute pancreatitis (SAP) with organ failure. This may limit drug development in SAP. Dysregulated and hyperimmune responses are the root cause for organ failure in SAP. We established a rat model of SAP with organ failure and evaluated directly translatable, clinically relevant parameters of organ dysfunction. We also evaluated the effects of therapeutic administration of methylprednisolone (MP) and TNF-α antibody infimab (Infliximab biosimilar) on the severity of experimental SAP induced by the ligation of the main pancreatic duct in rats. Methods: SAP was induced in adult male Wistar rats (250-350 g) by ligating the main pancreatic duct proximal to the biliopancreatic junction. One-hour after the procedure, therapeutic medication was administered intraperitoneally. Experiments were done in duplicate(batches of 3 rats/group) in sham surgery, SAP, SAP+MP, and SAP+infimab groups. At 0 (pre-intervention) and 48 hours (post-intervention), invasive BP, heart rate, serum amylase, lactate, paO2, SpO2, pH, renal and liver function were measured. Rats were sacrificed at 48 hours and the harvested pancreas, kidney and lung tissues were assessed histopathologically. Results: There was a significant increase in serum amylase level (p=0.019) and histopathological scores (p=0.003) in the SAP group as compared to sham surgery with no significant effect of either MP or Infimab (amylase:p = 0.211, histopathological score:p = 0.103). Both MP and Infimab significantly prevented a fall in BP and decrease in SpO2 following induction of SAP compared to the vehicle control (Table1). Conclusions: Therapeutic administration of MP or Infimab ameliorates the systemic inflammation and organ dysfunction associated with SAP in rats.Tabled 1EP02A-024SAP (Vehicle control)SAP + IP MethylprednisoloneSAP + IP Infimabp value for between group comparison of change following intervention (vehicle control vs MP vs Infimab )Change* following Interventionp value of change*Change following Interventionp value of change*Change* following Interventionp value of change*Amylase (IU/L)2681 (1072 to 3753)0.0043260 (1490 to 9960)0.0621457.5 (370 to 2350)0.0310.211Mean BP (mmHg)-15.4 (-17 to -13.4)0.004-3.6 (-6 to 6)0.688-19.3 (-28.6 to -3.9)0.0940.023Heart Rate (beats/min)-47 (-57.1 to -36.5)0.004-6.4 (-31.3 to -2.3)0.313-15.1 (-37.3 to 1.8)0.4380.133Blood Lactate (mmol/L)2.3 (0.7 - 2.7)0.0091.8 (1.2 - 2.3)0.0312.05 (0.2 - 2.3)0.0630.845SpO2 (%)-3.5 (-9.5 to -1.9)0.008-0.5 (-5.9 to 2.9)0.688-0.4 (-0.2 to 0)0.5840.176pO2 (mmHg)-5 (-31.9 to -0.9)0.074-3.7 (-65.6 to 9.5)0.563-6.7 (-16.1 to 1.9)0.2190.786*change refers to difference between the pre - intervention and post - intervention values Open table in a new tab *change refers to difference between the pre - intervention and post - intervention values

Electroacupuncture Ameliorates Acute Pancreatitis: A Role for the Vagus Nerve-Mediated Cholinergic Anti-Inflammatory Pathway.

Organ failure resulting from excessive inflammation is the leading cause of death in the early phase of acute pancreatitis (AP). The autonomic nervous system was reported to be involved in AP, and the vagus nerve could exert anti-inflammatory effects through α7 nicotinic acetylcholine receptor (α7nAChR) signaling. Acupuncture has been widely used in traditional Asian medicine, and recent studies suggested the inflammation modulating effect of electroacupuncture (EA) might be mediated by the autonomic nervous system. In this study, we aimed to investigate the effects of EA in AP animal models. Two independent AP mouse models were used, namely, caerulein hyperstimulation and pancreatic duct ligation. We found that EA at Zusanli acupoint increased vagus nerve activity, suppressed systemic inflammation, and alleviated the histopathological manifestations and leukocyte infiltrations of the pancreas. Induction of AP resulted in a remarkable decrease in the frequency of α7nAchR+ macrophages in the pancreas, while EA counteracted this phenomenon. The anti-inflammatory, pancreatic protective and upregulation of α7nAchR effects of EA were reduced in mice with vagotomy. Moreover, the therapeutic effects of EA were attenuated in mice treated with methyllycaconitine citrate, a selective α7nAChR antagonist. Taken together, EA could modulate inflammation, thereby exerting protective effects in AP. The mechanism may include activating the vagus nerve through the cholinergic anti-inflammatory pathway.

Pre-existing beta cells but not progenitors contribute to new beta cells in the adult pancreas.

It has been suggested that new beta cells can arise from specific populations of adult pancreatic progenitors or facultative stem cells. However, their existence remains controversial, and the conditions under which they would contribute to new beta-cell formation are not clear. Here, we use a suite of mouse models enabling dual-recombinase-mediated genetic tracing to simultaneously fate map insulin-positive and insulin-negative cells in the adult pancreas. We find that the insulin-negative cells, of both endocrine and exocrine origin, do not generate new beta cells in the adult pancreas during homeostasis, pregnancy or injury, including partial pancreatectomy, pancreatic duct ligation or beta-cell ablation with streptozotocin. However, non-beta cells can give rise to insulin-positive cells after extreme genetic ablation of beta cells, consistent with transdifferentiation. Together, our data indicate that pancreatic endocrine and exocrine progenitor cells do not contribute to new beta-cell formation in the adult mouse pancreas under physiological conditions.

Protectin D1 decreases pancreatitis severity in mice by inhibiting neutrophil extracellular trap formation

BackgroundDocosahexaenoic acid-derived protectin D1 (PD1) was identified critical in the resolution of inflammation in vivo, where it modulates the innate immune response and stimulates resolution. Acute pancreatitis (AP) is characterized by local pancreatic inflammation with mild forms whereas systemic inflammation with severe forms. Herein we investigate the impact of PD1 in murine models of pancreatitis. MethodsThree independent AP models, which induced in male mice via intraperitoneal injection of caerulein, L-arginine or pancreatic duct ligation, were used to confirm the protective effect of PD1. Infiltrationsof neutrophils and macrophages in pancreas were detected by flow cytometry and immunohistochemistry. In vitro and in vivo neutrophil extracellular traps formation was detected by immunofluorescence staining. Expression of peptidylarginine deiminase 4 (PAD4) in activated neutrophils was evaluated by western blotting. ResultsSystemic treatment with PD1 reduced serum activities of amylase and lipase, blunted the concentrations of tumor necrosis factor-α and interleukin-6 in serum and protected against pancreas histologic damage in three AP models. PD1 also prolonged the survival in the pancreatic duct ligation model. Moreover, pancreatic infiltrationofneutrophils and neutrophil CitH3 expression were reduced after PD1 administration. In vitro studies revealed PD1 decreased supernatant cell-free DNA and CitH3 levels and downregulated PAD4 expression in mouse bone-marrow derived neutrophils. However, in the caerulein mice pretreated with GSK484 hydrochloride, an inhibitor of PAD4, PD1 treatment showed no more protective effect. ConclusionsPD1 ameliorates AP by decreasing early infiltration of neutrophils into the pancreas and neutrophil extracellular traps formation through PAD4. These results supply the foundation to consider PD1 as a therapy for AP.

Risk Factors for Clinically Relevant Postoperative Pancreatic Fistula (CR-POPF) after Distal Pancreatectomy: A Single Center Retrospective Study.

Objectives Clinically relevant postoperative pancreatic fistula (CR-POPF) is the considerable contributor to major complications after pancreatectomy. The purpose of this study was to evaluate the potential risk factor contributing to CR-POPF following distal pancreatectomy (DP) and discuss the risk factors of pancreatic fistula in order to interpret the clinical importance. Methods In this retrospective study, 263 patients who underwent DP at Ningbo Medical Center Li Huili Hospital between January 2011 and January 2020 were reviewed in accordance with relevant guidelines and regulations. Patients' demographics and clinical parameters were evaluated using univariate and multivariate analyses to identify the risk factors contributing to CR-POPF. P < 0.05 was considered statistically significant. Results In all of the 263 patients with DP, pancreatic fistula was the most common surgical complication (19.0%). The univariate analysis of 18 factors showed that the patients with a malignant tumor, soft pancreas, and patient without ligation of the main pancreatic duct were more likely to develop pancreatic fistula. However, on multivariate analysis, the soft texture of the pancreas (OR = 2.381, 95% CI = 1.271–4.460, P=0.001) and the ligation of the main pancreatic duct (OR = 0.388, 95% CI = 0.207–0.726, P=0.002) were only an independent influencing factor for CR-POPF. Conclusions As a conclusion, pancreatic fistula was the most common surgical complication after DP. The soft texture of the pancreas and the absence of ligation of the main pancreatic duct can increase the risk of CR-POPF.