ceruletide has been researched along with Pancreatitis--Chronic* in 83 studies
83 other study(ies) available for ceruletide and Pancreatitis--Chronic
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Development and Characterization of Novel Chronic Eosinophilic Inflammation- Mediated Murine Model of Malignant Pancreatitis.
Develop a novel murine models of malignant pancreatitis.. Although patients with chronic pancreatitis are at a greater risk of developing pancreatic cancer, there is no definitive mouse model that currently develops chronic pancreatitis-induced pancreatic cancer.. Characterization of eosinophilic inflammation-mediated malignant pancreatitis in novel murine model.. We developed a murine model of chronic eosinophilic inflammation associated with pancreatitis that also shows characteristic features of pancreatic malignancy. The mouse received cerulein and azoxymethane via intraperitoneal administration developed pathological malignant phenotype, as well as concomitant lung inflammation.. We discovered pathological alterations in the pancreas that were associated with chronic pancreatitis, including a buildup of eosinophilic inflammation. Eosinophil degranulation was reported nearby in the pancreas tissue sections that show acinar-to-ductal metaplasia and acinar cell atrophy, both of which are characteristic of pancreatic malignancies. Additionally, we also observed the formation of PanIN lesions after three initial doses of AOM and eight weeks of cerulein with the AOM treatment regimen. We discovered that persistent pancreatic eosinophilic inflammation linked with a pancreatic malignant phenotype contributes to pulmonary damage. The RNA seq analysis also confirmed the induction of fibro-inflammatory and oncogenic proteins in pancreas and lung tissues. Further, in the current manuscript, we now report the stepwise kinetically time-dependent cellular inflammation, genes and proteins involved in the development of pancreatitis malignancy and associated acute lung injury by analyzing the mice of 3 AOM with 3, 8, and 12 weeks of the cerulein challenged protocol regime.. We first show that sustained long-term eosinophilic inflammation induces time-dependent proinflammatory, profibrotic and malignancy-associated genes that promote pancreatic malignancy and acute lung injury in mice. Topics: Animals; Ceruletide; Disease Models, Animal; Inflammation; Mice; Pancreatic Neoplasms; Pancreatitis, Chronic | 2023 |
XCHT alleviates the pancreatic fibrosis via VDR/NLRP3 signaling pathway in a mouse model of CP.
Xiao Chai Hu Tang (XCHT) derived from the classic medical book Shang Han Lun (Treatise on Febrile Diseases) in the Eastern Han Dynasty, which has been widely used in China and other Asian countries for the treatment of inflammation and fibrosis of chronic pancreatitis (CP), but the therapeutic mechanism of XCHT in pancreatic fibrosis remains unclear.. This study aimed to evaluate the intervention effects and explore pharmacological mechanism of XCHT on inflammation and fibrosis in cerulein-induced CP model.. Fifty male C57BL/6 mice were randomly divided into five main groups, 10 animals in each: Control, CP model (50 μg/kg cerulein), high dose XCHT-treated CP group (60 g/kg XCHT), medium dose XCHT-treated CP group (30 g/kg XCHT) and low dose XCHT-treated CP group (15 g/kg XCHT). Different doses of XCHT were given to mice by gavage twice a day for 2 weeks after the CP model induction. Pancreatic tissues were harvested and the pancreatic inflammation and fibrosis were evaluated by histological score, Sirius red staining, and alpha-smooth muscle actin (α-SMA) immunohistochemical staining. ELISA, IHC and RT-qPCR were performed to detect the expression of Vitamin D. The pathohistological results demonstrated that XCHT markedly inhibited the fibrosis and chronic inflammation of cerulein-induced CP, indicated by reduction of collagen I, collagen III, α-SMA, and NLRP3 expressions. XCHT significantly increased VD Topics: Actins; Animals; Ceruletide; Collagen; Disease Models, Animal; Fibrosis; Inflammasomes; Inflammation; Interleukin-6; Male; Mice; Mice, Inbred C57BL; NLR Family, Pyrin Domain-Containing 3 Protein; Pancreatitis, Chronic; Receptors, Calcitriol; Signal Transduction; Tumor Necrosis Factor-alpha; Vitamin D | 2023 |
The Kruppel-like factor 4-signal transducer and activator of transcription 5A axis promotes pancreatic fibrosis in mice with caerulein-induced chronic pancreatitis.
Pancreatic fibrosis (PF) is a hallmark of chronic pancreatitis (CP), but its molecular mechanism remains unclear. This study was conducted to explore the role of Kruppel-like factor 4 (KLF4) in PF in CP mice. The CP mouse model was established using caerulein. After KLF4 interference, pathological changes in pancreatic tissues and fibrosis degree were observed by hematoxylin-eosin staining and Masson staining, and levels of Collagen I, Collagen III, and alpha-smooth muscle actin, inflammatory cytokines, KLF4, signal transducer and activator of transcription 5A (STAT5) in pancreatic tissues were measured by enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, Western blot assay, and immunofluorescence. The enrichment of KLF4 on the STAT5 promoter and the binding of KLF4 to the STAT5 promoter were analyzed. The rescue experiments were performed by co-injection of sh-STAT5 and sh-KLF4 to confirm the regulatory mechanism of KLF4. KLF4 was upregulated in CP mice. Inhibition of KLF4 effectively attenuated pancreatic inflammation and PF in mice. KLF4 was enriched on the STAT5 promoter and enhanced the transcriptional and protein levels of STAT5. Overexpression of STAT5 reversed the inhibitory role of silencing KLF4 in PF. In summary, KLF4 promoted the transcription and expression of STAT5, which further facilitated PF in CP mice. Topics: Animals; Ceruletide; Fibrosis; Kruppel-Like Factor 4; Kruppel-Like Transcription Factors; Mice; Pancreatitis, Chronic; STAT5 Transcription Factor | 2023 |
Repetitive Cerulein-Induced Chronic Pancreatitis in Growing Pigs-A Pilot Study.
Chronic pancreatitis (CP) is an irreversible and progressive inflammatory disease. Knowledge on the development and progression of CP is limited. The goal of the study was to define the serum profile of pro-inflammatory cytokines and the cell antioxidant defense system (superoxidase dismutase-SOD, and reduced glutathione-GSH) over time in a cerulein-induced CP model and explore the impact of these changes on selected cytokines in the intestinal mucosa and pancreatic tissue, as well as on selected serum biochemical parameters. The mRNA expression of Topics: Animals; Ceruletide; Cytokines; Disease Models, Animal; Inflammation; Interleukin-6; Pancreas; Pancreatitis, Chronic; Pilot Projects; RNA, Messenger; Superoxide Dismutase; Swine; Tumor Necrosis Factor-alpha | 2023 |
Nintedanib Alleviates Chronic Pancreatitis by Inhibiting the Activation of Pancreatic Stellate Cells via the JAK/STAT3 and ERK1/2 Pathways.
Nintedanib (Ninte) has been approved for the treatment of pulmonary fibrosis, and whether it can ameliorate chronic pancreatitis (CP) is unknown.. This study was conducted to investigate the effect and molecular mechanism of Ninte on pancreatic fibrosis and inflammation in vivo and in vitro.. The caerulein-induced CP model of murine was applied, and Ninte was orally administered. Pathological changes in pancreas were evaluated using hematoxylin & eosin, Sirius Red, Masson's trichrome, and anti-Ki-67 staining. For in vitro studies, the effects of Ninte on cell viability, apoptosis, and migration of pancreatic stellate cells (PSCs) were determined by CCK-8, flow cytometry, and wound healing assays, respectively. The potential molecular mechanisms of the effects of Ninte on PSCs were analyzed by RNA-Seq and verified at the gene expression and protein activity levels by qRT-PCR and Western Blot.. Ninte significantly alleviated the weight loss in mice with caerulein-induced CP and simultaneously attenuated the pancreatic damage, as evidenced by reduced acinar atrophy, collagen deposition, infiltration of inflammatory cells, and inhibited cell proliferation/regeneration. Besides, Ninte markedly suppressed the transcription of fibrogenic and proinflammatory genes in pancreatic tissues. Further in vitro studies showed that Ninte significantly inhibited the transcription and protein expression of genes corresponding to fibrogenesis and proliferation in PSCs. The results of RNA-Seq analysis and subsequent verification assays indicated that Ninte inhibited the activation and proliferation of PSCs via the JAK/STAT3 and ERK1/2 pathways.. These findings indicate that Ninte may be a potential anti-inflammatory and anti-fibrotic therapeutic agent for CP. Topics: Animals; Ceruletide; Fibrosis; MAP Kinase Signaling System; Mice; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic | 2023 |
Kidney morphology and renal expression of aquaporins 2, 3 and 4 during cerulein - Induced chronic pancreatitis in pigs.
Chronic pancreatitis (CP) is associated with serious complications and reduced quality of life. Kidney failure is a frequent complication of acute pancreatitis (AP), however limited information is available regarding the impact of CP on this condition. In the kidney, 9 aquaporins (AQPs) are expressed to maintain body water homeostasis and concentrate urine. The purpose of this study was to morphologically assess and analyze the location and expression of AQP2, AQP3 and AQP4 and determine whether CP affects renal structure and expression of AQPs in collecting duct (CD) principal cells.. CP was induced in domestic pigs through intramuscular injections of cerulein (1 μg/kg bw/day for 6 days; n = 5); pigs without CP (n = 5) were used as a control group. Kidney samples were collected 6 weeks after the last injection and subjected to histological examination. Expression of AQPs was determined by immunohistochemistry and Western blot.. The kidneys of animals with CP exhibited moderate changes, including glomerular enlargement, increased collagen percentage, numerous stromal erythrorrhages and inflammatory infiltrations compared to control group. Although the total abundance of AQP2 in the CD decreased in pigs after cerulein administration, the difference was not statistically significant. Expression of AQP3 and AQP4 was limited to the basolateral membrane of the CD cells. AQP4 abundance remained relatively stable in both groups, while AQP3 expression increased nearly three-fold in pigs with CP.. This study identified morphological alterations and a statistically significant increase in the expression of renal AQP3 when pigs developed CP. Topics: Acute Disease; Animals; Aquaporin 2; Aquaporin 3; Ceruletide; Kidney; Pancreatitis, Chronic; Quality of Life; Swine | 2023 |
Catechin hydrate ameliorates cerulein‑induced chronic pancreatitis via the inactivation of TGF‑β/Smad2 signaling.
Chronic pancreatitis (CP) is a pancreatic inflammatory disease associated with histological changes, including fibrosis, acinar cell loss and immune cell infiltration, and leads to damage of the pancreas, which results in pain, weight loss and loss of pancreas function. Catechin or catechin hydrate (CH) has antioxidant, anticancer and immune‑regulatory effects. However, unlike other catechins, the antifibrotic effects of (+)‑CH have not been widely studied in many diseases, including CP. Therefore, the anti‑fibrotic effects of (+)‑CH against CP were evaluated in the present study. To assess the prophylactic effects of CH, (+)‑CH (1, 5 or 10 mg/kg) or ethanol was administered 1 h before first cerulein (50 µg/kg) injection. To assess the therapeutic effects, (+)‑CH (5 mg/kg) or ethanol was administered after cerulein injection for one or two weeks. In both methods, cerulein was injected intraperitoneally into mice once every hour, six times a day, four times a week, for a total of three weeks, to induce CP. The data showed that (+)‑CH markedly inhibited glandular destruction and inflammation during CP. Moreover, (+)‑CH prevented pancreatic stellate cell (PSC) activation and the production of extracellular matrix components, such as fibronectin 1 and collagens, which suggested that it may act as a novel therapeutic agent. Furthermore, the mechanism and effectiveness of (+)‑CH on pancreatic fibrosis were investigated in isolated PSCs. (+)‑CH suppressed the activation of Smad2 and fibrosis factors that act through transforming growth factor‑β (TGF‑β) or platelet‑derived growth factor. These findings suggest that (+)‑CH exhibits antifibrotic effects in cerulein‑induced CP by inactivating TGF‑β/Smad2 signaling. Topics: Animals; Catechin; Ceruletide; Ethanol; Mice; Pancreas; Pancreatic Diseases; Pancreatitis, Chronic | 2023 |
Chronic pancreatitis in a caerulein-induced mouse model is associated with an altered gut microbiome.
Chronic pancreatitis (CP) is an inflammatory disease of the pancreas with loss of exocrine/endocrine functions as well as development of fibrosis. Dysbiosis of gut microbiome has been shown to be involved in the pathogenesis of many disease processes. Therefore, we aim to investigate the alteration in gut microbiome associated with CP in caerulein-induced mouse model.. CP was induced in C57Bl/6 by using caerulein injections (50 μg/kg/h, i.p., x7, twice weekly for 10 weeks). Stool samples were collected either one week after end of injection (10-week CP) or 6 weeks (16-week CP). DNA was extracted from stool samples and V4 region of 16S rDNA was sequenced for microbiome analysis.. CP was strongly associated with the alteration in the composition of the gut microbiome, evidenced by differences in α and β diversity. When β diversity was measured using both weighted and unweighted UniFrac distances, stool from control mice is significantly different from mice on 10-week or 16-week CP (q < 0.01). The α-diversity measured by Faith's phylogenetic diversity was lowest in stool from healthy control and highest in stool from mice with 16-week CP (p < 0.001). Bacteria taxa differentially enriched in CP samples were detected using linear discriminant analysis. Bacteria from genera Bifidobacterium, Akkermansia, and Desulfovibrio were enriched in samples from 10-week CP mice. Bacteria from genera Allobaculum, Prevotella, and Bacteroides were enriched in samples from 16-week CP mice.. Together, these analyses reveal pronounced alteration in the gut microbiome composition, diversity, and function when mice develop CP. Topics: Animals; Bacteria; Ceruletide; Disease Models, Animal; Feces; Gastrointestinal Microbiome; Mice; Microbiota; Pancreatitis, Chronic; Phylogeny | 2022 |
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Topics: Animals; Ceruletide; Collagen; Fibrosis; Fraxinus; Humans; Mice; Pancreas; Pancreatitis, Chronic; Plant Bark; Signal Transduction; Transforming Growth Factor beta | 2022 |
The CEL-HYB1 Hybrid Allele Promotes Digestive Enzyme Misfolding and Pancreatitis in Mice.
A hybrid allele that originated from homologous recombination between CEL and its pseudogene (CELP), CEL-HYB1 increases the risk of chronic pancreatitis (CP). Although suggested to cause digestive enzyme misfolding, definitive in vivo evidence for this postulate has been lacking.. CRISPR-Cas9 was used to generate humanized mice harboring the CEL-HYB1 allele on a C57BL/6J background. Humanized CEL mice and C57BL/6J mice were used as controls. Pancreata were collected and analyzed by histology, immunohistochemistry, immunoblotting, and transcriptomics. Isolated pancreatic acini were cultured in vitro to measure the secretion and aggregation of CEL-HYB1 protein. Mice were given caerulein injections to induce acute pancreatitis (AP) and CP.. Pancreata from mice expressing CEL-HYB1 developed pathological features characteristic of focal pancreatitis that included acinar atrophy and vacuolization, inflammatory infiltrates, and fibrosis in a time-dependent manner. CEL-HYB1 expression in pancreatic acini led to decreased secretion and increased intracellular aggregation and triggered endoplasmic reticulum stress compared with CEL. The autophagy levels of pancreata from mice expressing CEL-HYB1 changed at different developmental stages; some aged CEL-HYB1 mice exhibited an accumulation of large autophagic vesicles and impaired autophagy in acinar cells. Administration of caerulein increased the severity of AP/CP in mice expressing CEL-HYB1 compared with control mice, accompanied by higher levels of endoplasmic reticulum stress.. Expression of a humanized form of CEL-HYB1 in mice promotes endoplasmic reticulum stress and pancreatitis through a misfolding-dependent pathway. Impaired autophagy appears to be involved in the pancreatic injury in aged CEL-HYB1 mice. These mice have the potential to be used as a model to identify therapeutic targets for CP. Topics: Acute Disease; Alleles; Animals; Ceruletide; Mice; Mice, Inbred C57BL; Pancreatitis, Chronic | 2022 |
A Mouse Model of Acute and Chronic Pancreatitis.
Pancreatitis occurs in two forms defined by its chronicity. Acute pancreatitis (AP) occurs suddenly and only lasts for several days. Consequently, most patients with AP recover without permanent damage to the pancreas, and about 20% of patients with AP have severe disease. In contrast, chronic pancreatitis (CP) is a long-lasting inflammation that causes permanent damage to pancreatic tissue; consequently, this form is marked by the emergence of persistent endocrine and exocrine pancreatic insufficiency. Despite these differences, AP and CP share central mechanisms of disease: in both forms, inflammation is initiated and/or sustained by the intrapancreatic activation of pancreatic digestive enzymes followed by the autodigestion of pancreatic tissues. In addition, in both forms enzymatic damage is accompanied by changes in intestinal permeability and entry of commensal organisms into the pancreas where they elicit innate immune responses that ultimately dominate and define pancreatic inflammation. In the murine models of AP and CP described here, both of these elements of pancreatitis pathogenesis are taken into account. Thus, in one approach mice are administered high doses of cerulein, a cholecystokinin analog with the ability at this dose to induce excessive activation of the cholecystokinin receptor expressed in pancreatic acinar cells and the release of active trypsin that causes both direct and indirect acinar damages due to entry of commensal organisms and stimulation of innate immune responses. In a second approach mice are administered low doses of cerulein, which causes little or no damage to the pancreas unless given along with nucleotide-binding oligomerization domain 1 (NOD1) ligand, which in the presence of low-dose cerulein administration induces a pathologic innate immune response mediated by NOD1. These approaches are adopted to produce AP when cerulein or cerulein plus NOD1 ligand is applied only once or to produce CP when a similar regimen is applied multiple times. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Cerulein-induced acute pancreatitis Alternate Protocol 1: Acute pancreatitis induced by cerulein and NOD1 ligand Basic Protocol 2: Cerulein-induced chronic pancreatitis Alternate Protocol 2: Chronic pancreatitis induced by cerulein and NOD1 ligand Support Protocol: Isolation of pancreatic mononuclear cells. Topics: Acute Disease; Animals; Ceruletide; Disease Models, Animal; Humans; Inflammation; Ligands; Mice; Pancreatitis, Chronic | 2022 |
Trimetazidine has Promising Preventive Effects on Experimental Chronic Pancreatitis Rat Model.
It was aimed to evaluate the preventive efficacy of trimetazidine in an experimental chronic pancreatitis rat model.. Chronic pancreatitis model was accomplished with caerulein and alcohol administration. In the study, 40 female Sprague Dawley rats were randomized into 5 groups containing 8 animals in each. Group 1 (chronic pancreatitis); group 2 (chronic pancreati- tis+low-dose trimetazidine group); group 3 (chronic pancreatitis+high-dose trimetazidine group); group 4 (placebo group (chronic pancreatitis + saline)); group 5 (sham group). 24 hours after the last injection, all animals were sacrificed. Tumor necrosis factor-alpha, transforming growth factor-β, malondialdehyde, and glutathione peroxidase levels were tested in blood samples. Histopathologic exam- inations were conducted by a senior pathologist who was unaware of the group allocations.. Results of biochemical parameters of the trimetazidine groups (groups 2 and 3) were significantly favorable compared with the chronic pancreatitis group (group 1) (P < .05). The difference between the low-dose- and the high-dose trimetazidine group (group 3) was significant in terms of blood tests (P < .05). The difference between the low-dose trimetazidine group and the chronic pancreatitis group was not significant in terms of histopathologic scores (P > .05); however, the difference was significant between the high-dose trimetazidine group and the chronic pancreatitis group (P < .05).. To the best of our knowledge, this current research is the first study that evaluates trimetazidine's efficacy in the chronic pancreatitis rat model. Trimetazidine has affirmative preventive properties in the chronic pancreatitis course. Topics: Animals; Ceruletide; Female; Humans; Malondialdehyde; Pancreatitis, Chronic; Rats; Rats, Sprague-Dawley; Trimetazidine | 2022 |
Pirfenidone ameliorates chronic pancreatitis in mouse models through immune and cytokine modulation.
Chronic pancreatitis (CP) is an irreversible fibro-inflammatory disease of the pancreas with no current targeted therapy. Pirfenidone, an anti-fibrotic and anti-inflammatory drug, is FDA approved for treatment of Idiopathic Pulmonary Fibrosis (IPF). Its efficacy in ameliorating CP has never been evaluated before. We recently reported that pirfenidone improves acute pancreatitis in mouse models. The aim of the current study was to evaluate the therapeutic efficacy of pirfenidone in mouse models of CP. We used caerulein and L-arginine models of CP and administered pirfenidone with ongoing injury, or in well-established disease. We evaluated for fibrosis by Sirius-red staining for collagen, immunohistochemistry, western blotting, and qPCR for fibrosis markers to show the salutary effects of pirfenidone in CP. Our results suggest that treatment with pirfenidone ameliorated CP related changes in the pancreas (i.e., atrophy, acinar cell loss, fibrosis, and inflammation) not only when administered with ongoing injury, but also in well-established models of caerulein as well as L-arginine induced CP. It reduces the pro-fibrotic phenotype of macrophages (in-vivo and in-vitro), reduces macrophage infiltration into the pancreas and alters the intra-pancreatic cytokine milieu preceding changes in histology. The therapeutic effect of pirfenidone is abrogated in absence of macrophages. Furthermore, it reduces collagen secretion, cytokine levels and fibrosis markers in pancreatic stellate cells in-vitro. As it is FDA approved, our findings in mouse models simulating clinical presentation of patients to the clinic, can be used as the basis of a clinical trial evaluating the efficacy of this drug as a therapeutic agent for CP. Topics: Acute Disease; Animals; Arginine; Ceruletide; Collagen; Cytokines; Disease Models, Animal; Fibrosis; Humans; Mice; Pancreatitis, Chronic; Pyridones | 2022 |
The development of cigarette smoke induced chronic pancreatitis in mice is associated with increased expression of K-Ras and NF-κB.
Epidemiological studies have demonstrated a strong association between cigarette smoking (CS) and chronic pancreatitis (CP); however, the exact mechanisms of this phenomenon remains unknown. The authors have previously shown that increased Ras expression activates the NF-κB mediated pathway and promotes development of CP. However, it is unclear whether a similar phenomenon occurs in CS-induced CP. Therefore, the aim of the study was to determine whether CS increases the expression of K-Ras, and promotes the development of CP in mice exposed to repeated episodes of acute pancreatitis (AP).. C57BL6/cmdb mice were exposed to CS or a sham treatment for 12 weeks. After one week of exposure, half of the animals from both groups were additionally subjected to repeated cerulein treatment (once a week, for 10 consecutive weeks) to mimic recurrent episodes of AP. Extension of pancreatic damage was determined histologically by H&E and Trichrome staining. The expression of K-Ras protein and downstream components (NF-κB, Cox-2, TGF-β) was evaluated by immunohistochemistry.. C57BL6/cmdb mice exposed to CS or cerulein alone did not develop any chronic pancreatic damage. However, concomitant treatment with both of these agents caused focal acinar atrophy, with slight intralobular and perivascular areas of fibrosis, and inflammatory cells infiltration resembling mild CP. Moreover, immunohistochemistry examinations revealed increased pancreatic expression of K-Ras and NF-κB only in mice treated both with CS and cerulein.. CS promotes development of CP in mice exposed to repeated episodes of AP. This process may be, at least partially, related to increased expression of K-Ras and NF-κB protein. Topics: Acute Disease; Animals; Ceruletide; Cigarette Smoking; Disease Models, Animal; Mice; Mice, Inbred C57BL; NF-kappa B; Pancreatitis, Chronic; Proto-Oncogene Proteins p21(ras) | 2022 |
Malondialdehyde-Acetaldehyde Extracellular Matrix Protein Adducts Attenuate Unfolded Protein Response During Alcohol and Smoking-Induced Pancreatitis.
Epidemiological studies have established alcohol and smoking as independent risk factors for recurrent acute pancreatitis and chronic pancreatitis. However, the molecular players responsible for the progressive loss of pancreatic parenchyma and fibroinflammatory response are poorly characterized.. Tandem mass tag-based proteomic and bioinformatics analyses were performed on the pancreata of mice exposed to alcohol, cigarette smoke, or a combination of alcohol and cigarette smoke. Biochemical, immunohistochemistry, and transcriptome analyses were performed on the pancreatic tissues and primary acinar cells treated with cerulein in combination with ethanol (50 mmol/L) and cigarette smoke extract (40 μg/mL) for the mechanistic studies.. A unique alteration in the pancreatic proteome was observed in mice exposed chronically to the combination of alcohol and cigarette smoke (56.5%) compared with cigarette smoke (21%) or alcohol (17%) alone. The formation of toxic metabolites (P < .001) and attenuated unfolded protein response (P < .04) were the significantly altered pathways on combined exposure. The extracellular matrix (ECM) proteins showed stable malondialdehyde-acetaldehyde (MAA) adducts in the pancreata of the combination group and chronic pancreatitis patients with a history of smoking and alcohol consumption. Interestingly, MAA-ECM adducts significantly suppressed expression of X-box-binding protein-1, leading to acinar cell death in the presence of alcohol and smoking. The stable MAA-ECM adducts persist even after alcohol and smoking cessation, and significantly delay pancreatic regeneration by abrogating the expression of cyclin-dependent kinases (CDK7 and CDK5) and regeneration markers.. The combined alcohol and smoking generate stable MAA-ECM adducts that increase endoplasmic reticulum stress and acinar cell death due to attenuated unfolded protein response and suppress expression of cell cycle regulators. Targeting aldehyde adducts might provide a novel therapeutic strategy for the management of recurrent acute pancreatitis and chronic pancreatitis. Topics: Acetaldehyde; Acute Disease; Aldehydes; Animals; Ceruletide; Cyclin-Dependent Kinases; Ethanol; Extracellular Matrix Proteins; Malondialdehyde; Mice; Pancreatitis, Chronic; Proteome; Proteomics; Smoking; Unfolded Protein Response | 2022 |
Intraductal pressure in experimental models of acute and chronic pancreatitis in mice.
Pancreatic intraductal pressure is related to the development of pancreatitis, including post-ERCP (endoscopic retrograde cholangiopancreatography) pancreatitis. In this study, we investigate pancreatic intraductal pressure in various mouse models of acute and chronic pancreatitis.. Post-ERCP pancreatitis was induced by retrograde infusion of normal saline or radiocontrast at the constant rate of 10 or 20 μL/min. Obstructive pancreatitis was induced by ligation of the pancreatic duct followed by a single injection of caerulein and the changes of intraductal pressure were recorded in day 3 for obstructive acute pancreatitis and day 14 for obstructive chronic pancreatitis. Non-obstructive pancreatitis was induced by repetitive intraperitoneal injections of caerulein. The changes of intraductal pressure were recorded right after the last caerulein injection for non-obstructive acute pancreatitis and after the completion of 4-week caerulein injections for non-obstructive chronic pancreatitis.. Elevated pancreatic intraductal pressure was observed in both normal saline and radiocontrast infusion groups and was furtherly indicated that was positively correlated with the viscosity of solution but not genders. In the models of obstructive pancreatitis, a rise in intraductal pressure was observed in both acute and chronic pancreatitis; whereas in the models of non-obstructive pancreatitis, a rise in intraductal pressure was only observed in chronic, but not acute pancreatitis.. During ERCP, the elevations in pancreatic intraductal pressure are induced by increasing rate or viscous solution of infusion. During different forms of experimental acute and chronic pancreatitis, obstructive or non-obstructive etiologies of pancreatitis also induces the elevations in pancreatic intraductal pressure. Topics: Animals; Ceruletide; Cholangiopancreatography, Endoscopic Retrograde; Disease Models, Animal; Mice; Pancreatitis, Chronic; Saline Solution | 2022 |
Acinar ATP8b1/LPC pathway promotes macrophage efferocytosis and clearance of inflammation during chronic pancreatitis development.
Topics: Acinar Cells; Adenosine Triphosphatases; Animals; Ceruletide; Histones; Inflammation; Lysophosphatidylcholines; Macrophages; Mice; Pancreatitis, Chronic; Phospholipid Transfer Proteins; Transcription Factors | 2022 |
Poly(ADP-Ribose) Polymerase 1 Promotes Inflammation and Fibrosis in a Mouse Model of Chronic Pancreatitis.
Chronic pancreatitis (CP) is an inflammatory disease of the pancreas characterized by ductal obstructions, tissue fibrosis, atrophy and exocrine and endocrine pancreatic insufficiency. However, our understanding is very limited concerning the disease's progression from a single acute inflammation, via recurrent acute pancreatitis (AP) and early CP, to the late stage CP. Poly(ADP-ribose) polymerase 1 (PARP1) is a DNA damage sensor enzyme activated mostly by oxidative DNA damage. As a co-activator of inflammatory transcription factors, PARP1 is a central mediator of the inflammatory response and it has also been implicated in acute pancreatitis. Here, we set out to investigate whether PARP1 contributed to the pathogenesis of CP. We found that the clinically used PARP inhibitor olaparib (OLA) had protective effects in a murine model of CP induced by multiple cerulein injections. OLA reduced pancreas atrophy and expression of the inflammatory mediators TNFα and interleukin-6 (IL-6), both in the pancreas and in the lungs. Moreover, there was significantly less fibrosis (Masson's trichrome staining) in the pancreatic sections of OLA-treated mice compared to the cerulein-only group. mRNA expression of the fibrosis markers TGFβ, smooth muscle actin (SMA), and collagen-1 were markedly reduced by OLA. CP was also induced in PARP1 knockout (KO) mice and their wild-type (WT) counterparts. Inflammation and fibrosis markers showed lower expression in the KO compared to the WT mice. Moreover, reduced granulocyte infiltration (tissue myeloperoxidase activity) and a lower elevation of serum amylase and lipase activity could also be detected in the KO mice. Furthermore, primary acinar cells isolated from KO mice were also protected from cerulein-induced toxicity compared to WT cells. In summary, our data suggest that PARP inhibitors may be promising candidates for repurposing to treat not only acute but chronic pancreatitis as well. Topics: Acinar Cells; Acute Disease; Animals; Ceruletide; Disease Models, Animal; Fibrosis; Inflammation; Interleukin-6; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Pancreas; Pancreatitis; Pancreatitis, Chronic; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha | 2021 |
Dysregulation of PI3K and Hippo signaling pathways synergistically induces chronic pancreatitis via CTGF upregulation.
The role of PI3K and Hippo signaling in chronic pancreatitis (CP) pathogenesis is unclear. Therefore, we assessed the involvement of these pathways in CP by examining the PI3K and Hippo signaling components PTEN and SAV1, respectively. We observed significant decreases in pancreatic PTEN and SAV1 levels in 2 murine CP models: repeated cerulein injection and pancreatic ductal ligation. Additionally, pancreas-specific deletion of Pten and Sav1 (DKO) induced CP in mice. Pancreatic connective tissue growth factor (CTGF) was markedly upregulated in both CP models and DKO mice, and pancreatic CCAAT/enhancer-binding protein-α (CEBPA) expression was downregulated in the CP models. Interestingly, in pancreatic acinar cells (PACs), CEBPA knockdown reduced PTEN and SAV1 and increased CTGF levels in vitro. Furthermore, CEBPA knockdown in PACs induced acinar-to-ductal metaplasia and activation of cocultured macrophages and pancreatic stellate cells. These results were mitigated by CTGF inhibition. CP in DKO mice was also ameliorated by Ctgf gene deletion, and cerulein-induced CP was alleviated by antibody-mediated CTGF neutralization. Finally, we observed significantly decreased PTEN, SAV1, and CEBPA and increased CTGF levels in human CP tissues compared with nonpancreatitis tissues. Taken together, our results indicate that dysregulation of PI3K and Hippo signaling induces CP via CTGF upregulation. Topics: Animals; CCAAT-Enhancer-Binding Proteins; Cell Cycle Proteins; Ceruletide; Coculture Techniques; Connective Tissue Growth Factor; Disease Models, Animal; Down-Regulation; Hippo Signaling Pathway; Humans; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Pancreatic Stellate Cells; Pancreatitis, Chronic; Phosphatidylinositol 3-Kinases; Protein Serine-Threonine Kinases; PTEN Phosphohydrolase; Signal Transduction; Up-Regulation | 2021 |
Distinct Murine Pancreatic Transcriptomic Signatures during Chronic Pancreatitis Recovery.
We have previously demonstrated that the pancreas can recover from chronic pancreatitis (CP) lesions in the cerulein-induced mouse model. To explore how pancreatic recovery is achieved at the molecular level, we used RNA-sequencing (seq) and profiled transcriptomes during CP transition to recovery. CP was induced by intraperitoneally injecting cerulein in C57BL/6 mice. Time-matched controls (CON) were given normal saline. Pancreata were harvested from mice 4 days after the final injections (designated as CP and CON) or 4 weeks after the final injections (designated as CP recovery (CPR) and control recovery (CONR)). Pancreatic RNAs were extracted for RNA-seq and quantitative (q) PCR validation. Using RNA-seq, we identified a total of 3,600 differentially expressed genes (DEGs) in CP versus CON and 166 DEGs in CPR versus CONR. There are 132 DEGs overlapped between CP and CPR and 34 DEGs unique to CPR. A number of selected pancreatic fibrosis-relevant DEGs were validated by qPCR. The top 20 gene sets enriched from DEGs shared between CP and CPR are relevant to extracellular matrix and cancer biology, whereas the top 10 gene sets enriched from DEGs specific to CPR are pertinent to DNA methylation and specific signaling pathways. In conclusion, we identified a distinct set of DEGs in association with extracellular matrix and cancer cell activities to contrast CP and CPR. Once during ongoing CP recovery, DEGs relevant to DNA methylation and specific signaling pathways were induced to express. The DEGs shared between CP and CPR and the DEGs specific to CPR may serve as the unique transcriptomic signatures and biomarkers for determining CP recovery and monitoring potential therapeutic responses at the molecular level to reflect pancreatic histological resolution. Topics: Animals; Ceruletide; Cholecystokinin; Disease Models, Animal; Extracellular Matrix; Female; Gene Expression Profiling; Gene Expression Regulation; Male; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; RNA-Seq; Signal Transduction; Transcriptome | 2021 |
Identification of Novel Ligands for Targeted Antifibrotic Therapy of Chronic Pancreatitis.
Chronic pancreatitis (CP) is an inflammatory disorder of the pancreas that leads to impaired pancreatic function. The limited therapeutic options and the lack of molecular targeting ligands or non-serum-based biomarkers hinder the development of target-specific drugs. Thus, there is a need for an unbiased, comprehensive discovery and evaluation of pancreatitis-specific ligands.. This study utilized a computational-guided in vivo phage display approach to select peptide ligands selective for cellular components in the caerulein-induced mouse model of CP. The identified peptides were conjugated to pegylated DOPC liposomes via the reverse-phase evaporation method, and the in vivo specificity and pharmacokinetics were determined. As proof of concept, CP-targeted liposomes were used to deliver an antifibrotic small molecular drug, apigenin. Antifibrotic effects determined by pancreatic histology, fibronectin expression, and collagen deposition were evaluated.. We have identified five peptides specific for chronic pancreatitis and demonstrated selectivity to activated pancreatic stellate cells, acinar cells, macrophages, and extracellular matrix, respectively. MDLSLKP-conjugated liposomes demonstrated an increased particle accumulation by 1.3-fold in the inflamed pancreas compared to the control liposomes. We also observed that targeted delivery of apigenin resulted in improved acini preservation, a 37.2% and 33.1% respective reduction in collagen and fibronectin expression compared to mice receiving the free drug, and reduced oxidative stress in the liver.. In summary, we have developed a systematic approach to profile peptide ligands selective for cellular components of complex disease models and demonstrated the biomedical applications of the identified peptides to improve tissue remodeling in the inflamed pancreas. Topics: Animals; Ceruletide; Ligands; Mice; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic | 2021 |
Cholecystokinin Receptor Antagonist Therapy Decreases Inflammation and Fibrosis in Chronic Pancreatitis.
Chronic pancreatitis is associated with recurrent inflammation, pain, fibrosis, and loss of exocrine and endocrine pancreatic function and risk of cancer. We hypothesized that activation of the CCK receptor contributes to pancreatitis and blockade of this pathway would improve chronic pancreatitis.. Two murine models were used to determine whether CCK receptor blockade with proglumide could prevent and reverse histologic and biochemical features of chronic pancreatitis: the 6-week repetitive chronic cerulein injection model and the modified 75% choline-deficient ethionine (CDE) diet. In the CDE-fed model, half the mice received water supplemented with proglumide, for 18 weeks. After chronic pancreatitis was established in the cerulein model, half the mice were treated with proglumide and half with water. Histology was scored in a blinded fashion for inflammation, fibrosis and acinar ductal metaplasia (ADM) and serum lipase levels were measured. RNA was extracted and examined for differentially expressed fibrosis genes.. Proglumide therapy decreased pancreatic weight in the CDE diet study and the cerulein-induced chronic pancreatitis model. Fibrosis, inflammation, and ADM scores were significantly reduced in both models. Lipase values improved with proglumide but not in controls in both models. Proglumide decreased pancreas mRNA expression of amylase, collagen-4, and TGFβR2 gene expression by 44, 38, and 25%, respectively, compared to control mice.. New strategies are needed to decreased inflammation and reduce fibrosis in chronic pancreatitis. CCK receptor antagonist therapy may improve chronic pancreatitis by reversing fibrosis and inflammation. The decrease in ADM may reduce the risk of the development of pancreatic cancer. Topics: Animals; Ceruletide; Chronic Disease; Disease Models, Animal; Fibrosis; Inflammation; Lipase; Mice; Pancreas; Pancreatitis, Chronic; Proglumide; Receptors, Cholecystokinin | 2020 |
Hic-5 deficiency protects cerulein-induced chronic pancreatitis via down-regulation of the NF-κB (p65)/IL-6 signalling pathway.
Chronic pancreatitis (CP), characterized by pancreatic fibrosis, is a recurrent, progressive and irreversible disease. Activation of the pancreatic stellate cells (PSCs) is considered a core event in pancreatic fibrosis. In this study, we investigated the role of hydrogen peroxide-inducible clone-5 (Hic-5) in CP. Analysis of the human pancreatic tissue samples revealed that Hic-5 was overexpressed in patients with CP and was extremely low in healthy pancreas. Hic-5 was significant up-regulated in the activated primary PSCs independently from transforming growth factor beta stimulation. CP induced by cerulein injection was ameliorated in Hic-5 knockout (KO) mice, as shown by staining of tissue level. Simultaneously, the activation ability of the primary PSCs from Hic-5 KO mice was significantly attenuated. We also found that the Hic-5 up-regulation by cerulein activated the NF-κB (p65)/IL-6 signalling pathway and regulated the downstream extracellular matrix (ECM) genes such as α-SMA and Col1a1. Therefore, we determined whether suppressing NF-κB/p65 alleviated CP by treating mice with the NF-κB/p65 inhibitor triptolide in the cerulein-induced CP model and found that pancreatic fibrosis was alleviated by NF-κB/p65 inhibition. These findings provide evidence for Hic-5 as a therapeutic target that plays a crucial role in regulating PSCs activation and pancreatic fibrosis. Topics: Animals; Cells, Cultured; Ceruletide; Cytoskeletal Proteins; Disease Models, Animal; Diterpenes; DNA-Binding Proteins; Down-Regulation; Epoxy Compounds; Fibrosis; Interleukin-6; LIM Domain Proteins; Mice, Knockout; NF-kappa B; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Phenanthrenes; Signal Transduction; Transcription Factor RelA; Transforming Growth Factor beta | 2020 |
NADPH oxidase 1 mediates caerulein-induced pancreatic fibrosis in chronic pancreatitis.
Inflammatory disorders of the pancreas are divided into acute (AP) and chronic (CP) forms. Both states of pancreatitis are a result of pro-inflammatory mediators, including reactive oxygen species (ROS). One of the sources of ROS is NADPH oxidase (Nox). The rodent genome encodes Nox1-4, Duox1 and Duox2. Our purpose was to assess the extent to which Nox enzymes contribute to the pathogenesis of both AP and CP using Nox-deficient mice. Using RT-PCR, Nox1 was found in both isolated mouse pancreatic acini and pancreatic stellate cells (PaSCs). Subsequently, mice with genetically deleted Nox1 were further studied and showed that the histo-morphologic characteristics of caerulein-induced CP, but not caerulein-induced AP, was ameliorated in Nox1 KO mice. We also found that the lack of Nox1 impaired caerulein-induced ROS generation in PaSCs. Using Western blotting, we found that AKT mediates the fibrotic effect of Nox1 in a mouse model of CP. We also found a decrease in phospho-ERK and p38MAPK levels in Nox1 KO mice with CP, but not with AP. Both CP-induced TGF-β up-regulation and NF-ĸB activation were impaired in pancreas from Nox1 KO mice. Western blotting indicated increases in proteins involved in fibrosis and acinar-to-ductal metaplasia in WT mice with CP. No change in those proteins were observed in Nox1 KO mice. The lack of Nox1 lowered mRNA levels of CP-induced matrix metalloproteinase MMP-9 and E-cadherin repressor Twist in PaSCs. CONCLUSION: Nox1-derived ROS in PaSCs mediate the fibrotic process of CP by activating the downstream redox-sensitive signaling pathways AKT and NF-ĸB, up-regulating MMP-9 and Twist, and producing α-smooth muscle actin and collagen I and III. Topics: Animals; Ceruletide; Fibrosis; Mice; Mice, Knockout; NADH, NADPH Oxidoreductases; NADPH Oxidase 1; NADPH Oxidase 4; NADPH Oxidases; Pancreatitis, Chronic; Reactive Oxygen Species | 2020 |
Serotonin-RhoA/ROCK axis promotes acinar-to-ductal metaplasia in caerulein-induced chronic pancreatitis.
The underlying molecular mechanisms of chronic pancreatitis (CP) developing into pancreatic ductal adenocarcinoma (PDAC) remain largely unknown. Here we show that the level of serotonin in mouse pancreatic tissues is upregulated in caerulein-induced CP mice. In vitro study demonstrates that serotonin promotes the formation of acinar-to-ductal metaplasia (ADM) and the activation of pancreatic stellate cells (PSCs), which results from the activation of RhoA/ROCK signaling cascade. Activation of this signaling cascade increases NF-κB nuclear translocation and α-SMA expression, which further enhance the inflammatory responses and fibrosis in pancreatic tissues. Intriguingly, quercetin inhibits both ADM lesion and PSCs activation in vitro and in vivo via its inhibitory effect on serotonin release. Our findings underscore the instrumental role of serotonin-mediated activation of RhoA/ROCK signaling pathway in development of PDAC from CP and highlight a potential to impede PDAC development by disrupting tumor-promoting functions of serotonin. Topics: Acinar Cells; Animals; Biomarkers; Carcinoma, Pancreatic Ductal; Cell Transformation, Neoplastic; Ceruletide; Disease Models, Animal; Gene Expression Regulation; Immunohistochemistry; Metaplasia; Mice; Pancreatitis, Chronic; rho-Associated Kinases; rhoA GTP-Binding Protein; Serotonin; Signal Transduction | 2020 |
Nimbolide abrogates cerulein-induced chronic pancreatitis by modulating β-catenin/Smad in a sirtuin-dependent way.
Chronic pancreatitis (CP) is one of the leading causes of mortality worldwide with no clinically approved therapeutic interventions. The present study was designed to investigate the protective effect of nimbolide (NB), an active constituent of neem tree (Azadirachta indica), by targeting β-catenin/Smad/SIRT1 in cerulein-induced CP model. The effects of NB was investigated on cerulein (50 μg/kg/hr*6 exposures /day, 3 days a week for 3 weeks) induced CP in mice. Amylase and lipase activity were measured and histopathological evaluation was performed. Collagen deposition in the pancreatic tissue was estimated by hydroxyproline assay, and collagen specific staining picrosirius red and Masson's trichrome. Cerulein-induced CP was significantly controlled by NB treatment, as shown by the downregulation of β-catenin/Smad signaling in a SIRT1 dependent manner. NB treatment significantly decreased α-SMA, MMP-2, collagen1a, fibronectin, TGF-β1, p-Smad-2/3 expression and extracellular matrix (ECM) deposition in pancreatic tissue. However, the protective effects of NB on cerulein-induced CP were undermined by nicotinamide (NMD) or splitomicin, sirtuin 1 (SIRT1) inhibitors treatment. NB treatment modulated protein expression by activating SIRT1 and decreasing the expression of β-catenin/Smad proteins in CP mice. However, the expression of SIRT1 in pancreatic tissue was elevated by NB treatment and it was decreased by NMD or splitomicin treatment. In summary, our results strongly suggest that NB exerted promising protective effects in cerulein-induced CP model by inhibiting β-catenin/Smad in a sirtuin-dependent manner, which could be attributed to its anti-inflammatory and antifibrotic effects. Our study suggests that NB could be an effective therapeutic intervention for the treatment of CP. Topics: Animals; Anti-Inflammatory Agents; beta Catenin; Ceruletide; Cytokines; Disease Models, Animal; Extracellular Matrix; Fibrosis; Inflammation Mediators; Limonins; Male; Mice; Oxidative Stress; Pancreas; Pancreatitis, Chronic; Phosphorylation; Signal Transduction; Sirtuin 1; Smad2 Protein; Smad3 Protein | 2020 |
Isoliquiritigenin ameliorates caerulein-induced chronic pancreatitis by inhibiting the activation of PSCs and pancreatic infiltration of macrophages.
Chronic pancreatitis (CP) is characterized by persistent inflammation of the pancreas that results in progressive loss of the endocrine and exocrine compartment owing to atrophy and/or replacement with fibrotic tissue. Currently, the clinical therapeutic scheme of CP is mainly symptomatic treatment including pancreatic enzyme replacement, glycaemic control and nutritional support therapy, lacking of specific therapeutic drugs for prevention and suppression of inflammation and fibrosis aggravating in CP. Here, we investigated the effect of isoliquiritigenin (ILG), a chalcone-type dietary compound derived from licorice, on pancreatic fibrosis and inflammation in a model of caerulein-induced murine CP, and the results indicated that ILG notably alleviated pancreatic fibrosis and infiltration of macrophages. Further in vitro studies in human pancreatic stellate cells (hPSCs) showed that ILG exerted significant inhibition on the proliferation and activation of hPSCs, which may be due to negative regulation of the ERK1/2 and JNK1/2 activities. Moreover, ILG significantly restrained the M1 polarization of macrophages (RAW 264.7) via attenuation of the NF-κB signalling pathway, whereas the M2 polarization was hardly affected. These findings indicated that ILG might be a potential anti-inflammatory and anti-fibrotic therapeutic agent for CP. Topics: Animals; Cell Line; Cell Proliferation; Ceruletide; Chalcones; Fibrosis; Humans; Macrophages; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; NF-kappa B; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; RAW 264.7 Cells; Signal Transduction | 2020 |
Berberine attenuates severity of chronic pancreatitis and fibrosis via AMPK-mediated inhibition of TGF-β1/Smad signaling and M2 polarization.
Berberine (BR) acts as an AMP-activated protein kinase (AMPK) activator which possesses antioxidant and anti-inflammatory properties. In this study, we have investigated the effects of BR against cerulein-induced chronic pancreatitis (CP) via inhibition of TGF-β/Smad signaling and M2 macrophages polarization in AMPK dependent manner. Cerulein-induced CP mice were treated with BR (3 and 10 mg/kg), intraperitoneally every day for 21 days. Our results indicated that, BR treatment (10 mg/kg) significantly reduced oxidative-nitrosative stress, histological alterations, inflammatory cells infiltration and collagen deposition in pancreatic tissue. BR treatment also prevented cerulein-induced pancreatic stellate cells (PSCs) activation and extracellular matrix (ECM) deposition via downregulation of α-SMA, collagen1a, collagen3a and fibronectin expression. Mechanistically, treatment with BR significantly activated AMPK signaling as compared to cerulein-challenged mice. Further, administration of BR also inhibited TGF-β/Smad signaling and macrophages polarization in cerulein-induced CP in-vivo models and TGF-β1 stimulated RAW 264.7 macrophages in-vitro. Together, our results strongly suggest that BR treatment protected against cerulein-induced CP and associated fibrosis progression by inhibiting TGF-β1/Smad signaling and M2 macrophages polarization in an AMPK dependent manner. Topics: Actins; AMP-Activated Protein Kinase Kinases; Animals; Berberine; Ceruletide; Collagen Type I; Extracellular Matrix; Fibrosis; Gene Expression Regulation; Lectins, C-Type; Macrophages; Male; Mannose Receptor; Mannose-Binding Lectins; Mice; Nitrosative Stress; Oxidative Stress; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Protein Kinases; Random Allocation; RAW 264.7 Cells; Receptors, Cell Surface; Smad Proteins; Transforming Growth Factor beta1 | 2020 |
Impaired autophagy increases susceptibility to endotoxin-induced chronic pancreatitis.
Chronic pancreatitis (CP) is associated with elevated plasma levels of bacterial lipopolysaccharide (LPS) and we have demonstrated reduced acinar cell autophagy in human CP tissue. Therefore, we investigated the role of autophagy in experimental endotoxin-induced pancreatic injury and aimed to identify LPS in human CP tissue. Pancreatic Atg7-deficient mice were injected with a single sub-lethal dose of LPS. Expression of autophagy, apoptosis, necroptosis, and inflammatory markers was determined 3 and 24 h later utilizing immunoblotting and immunofluorescence. The presence of LPS in pancreatic tissue from mice and from patients and healthy controls was determined using immunohistochemistry, immunoblots, and chromogenic assay. Mice lacking pancreatic autophagy exhibited local signs of inflammation and were particularly sensitive to the toxic effect of LPS injection as compared to control mice. In response to LPS, Atg7 Topics: Acinar Cells; Animals; Autophagy; Ceruletide; Endotoxins; Humans; Inflammation; Lipopolysaccharides; Mice, Transgenic; Pancreatitis, Chronic | 2020 |
SPOP inhibits mice pancreatic stellate cell activation by promoting FADD degradation in cerulein-induced chronic pancreatitis.
Pancreatic stellate cells (PSCs) have been recognized as key mediators of pancreatic fibrosis, a characteristic feature of chronic pancreatitis (CP). As a cullin-based E3 ubiquitin ligase, speckle-type POZ protein (SPOP) has been identified to participate in tumorigenesis and organ development. However, its biological role in CP remains unknown. Therefore, this study sought to investigate the changed expression of SPOP in CP and to examine the effect on mice PSCs activation of SPOP. We found that SPOP was downregulated in the pancreatic tissues of cerulein-induced CP mice. siRNA-mediated knockdown of SPOP led to significant promotion in primary PSCs activity by activating the nuclear factor-kappaB (NF-κB)/interleukin-6 (IL-6) signaling pathway. In addition, we examined the effects of Fas-associated death domain (FADD), a proven SPOP substrate that activates NF-κB, on the regulation of PSCs activation. We found that FADD was downregulated by SPOP via interaction-mediated degradation, and was upregulated during PSCs activation. The promotion of PSCs activation in knocking down SPOP with siSPOP-1 were counteracted by knocking down FADD. The results suggest that the SPOP-induced inhibition of PSCs activation partially depended on FADD. These results highlight the importance of SPOP in CP and provide a potential target for therapeutic intervention. Topics: Animals; Cells, Cultured; Ceruletide; Death Domain; Down-Regulation; Fas-Associated Death Domain Protein; Fibrosis; Interleukin-6; Mice; NF-kappa B; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Signal Transduction; Up-Regulation | 2019 |
Dasatinib ameliorates chronic pancreatitis induced by caerulein via anti-fibrotic and anti-inflammatory mechanism.
Chronic pancreatitis (CP) is characterized by persistent inflammation and fibrosis of the pancreas. To date, no clinical therapy is available to reverse the inflammatory damage or pancreatic fibrosis associated with CP. This study systematically investigated the effect of Dasatinib, a multiple tyrosine kinases (TKs) inhibitor, on pancreatic fibrosis and inflammation in vivo and in vitro. We found that Dasatinib notably ameliorated pancreatic fibrosis and infiltration of macrophages in a model of caerulein-induced murine CP. Further RNA-seq and phosphoproteomic analysis and in vitro validation assays indicated that Dasatinib exerted a marked inhibition on the proliferation and activation of PSCs, which may be resulted from increased GSK3β-mediated β-catenin cytosol retention by inhibiting upstream multiple TKs (such as PDGFR and Src) and MAPK cascades (including ERK1/2 and p38 MAPK). In addition, Dasatinib significantly restrained both the M1 and M2 polarization of macrophages, and impeded its recruitment and crosstalk with PSCs. Our findings indicated that Dasatinib is a potential anti-inflammatory and anti-fibrotic therapeutic strategy for CP. Topics: Animals; Anti-Inflammatory Agents; Cell Movement; Ceruletide; Dasatinib; Fibrosis; Male; Mice; Mice, Inbred C57BL; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; RAW 264.7 Cells; Wound Healing | 2019 |
Tamoxifen affects chronic pancreatitis-related fibrogenesis in an experimental mouse model: an effect beyond Cre recombination.
Topics: Administration, Oral; Animals; Ceruletide; Disease Models, Animal; Female; Fibrosis; Male; Mice; Mice, Inbred C57BL; Pancreatitis, Chronic; Tamoxifen | 2019 |
Role of eosinophils in the initiation and progression of pancreatitis pathogenesis.
Eosinophilic pancreatitis (EP) is reported in humans; however, the etiology and role of eosinophils in EP pathogenesis are poorly understood and not well explored. Therefore, it is interesting to examine the role of eosinophils in the initiation and progression of pancreatitis pathogenesis. Accordingly, we performed anti-major basic protein immunostaining, chloroacetate esterase, and Masson's trichrome analyses to detect eosinophils, mast cells, and collagen in the tissue sections of mouse and human pancreas. Induced eosinophils accumulation and degranulation were observed in the tissue sections of human pancreatitis, compared with no eosinophils in the normal pancreatic tissue sections. Similarly, we observed induced tissue eosinophilia along with mast cells and acinar cells atrophy in cerulein-induced mouse model of chronic pancreatitis. Additionally, qPCR and ELISA analyses detected induced transcript and protein levels of proinflammatory and profibrotic cytokines, chemokines like IL 5, IL-18, eotaxin-1, eotaxin-2, TGF-β1, collagen-1, collagen-3, fibronectin, and α-SMA in experimental pancreatitis. Mechanistically, we show that eosinophil-deficient GATA1 and endogenous IL-5-deficient mice were protected from the induction of proinflammatory and profibrotic cytokines, chemokines, tissue eosinophilia, and mast cells in a cerulein-induced murine model of pancreatitis. These human and experimental data indicate that eosinophil accumulation and degranulation may have a critical role in promoting pancreatitis pathogenesis including fibrosis. Taken together, eosinophil tissue accumulation needs appropriate attention to understand and restrict the progression of pancreatitis pathogenesis in humans. NEW & NOTEWORTHY The present study for the first time shows that eosinophils accumulate in the pancreas and promote disease pathogenesis, including fibrosis in earlier reported cerulein-induced experimental models of pancreatitis. Importantly, we show that GATA-1 and IL-5 deficiency protects mice form the induction of eosinophil active chemokines, and profibrotic cytokines, including accumulation of tissue collagen in an experimental model of pancreatitis. Additionally, we state that cerulein-induced chronic pancreatitis is independent of blood eosinophilia. Topics: Animals; Cell Degranulation; Ceruletide; Collagen; Cytokines; Disease Models, Animal; Disease Progression; Eosinophils; Fibrosis; GATA1 Transcription Factor; Humans; Interleukin-5; Mast Cells; Mice, Inbred BALB C; Mice, Knockout; Pancreas; Pancreatitis, Chronic; Signal Transduction; Time Factors | 2018 |
Neuronal Transforming Growth Factor beta Signaling via SMAD3 Contributes to Pain in Animal Models of Chronic Pancreatitis.
Chronic pancreatitis (CP) is characterized by pancreatic inflammation and fibrosis, associated with increased pancreatic expression of transforming growth factor beta (TGFB). It is not clear how these might contribute to pain. We investigated whether TGFB signaling via SMAD induces sensitization of pancreatic sensory neurons to increase nociception.. CP was induced in Sprague-Dawley rats by infusion of trinitrobenzene sulfonic acid; some rats were given intrathecal infusions of TGFB1. CP was induced in control mice by administration of cerulein; we also studied β1glo/Ptf1acre-ER mice, which on induction overexpress TGFB1 in pancreatic acinar cells, and TGFBr1. Overexpression of TGFB in pancreatic acinar cells of mice and infusion of TGFB1 into rats resulted in sensory neuron hyperexcitability, SMAD3 activation, and increased nociception. This was accompanied by a reduction in the transient A-type current in pancreas-specific sensory neurons in rats, a characteristic of nociceptive sensitization in animal models of CP. Conversely, pancreata from TGFBr1. In pancreata of mice and rats, TGFB promotes peripheral nociceptive sensitization via a direct effect on primary sensory neurons mediated by intra-neuronal SMAD3. This is distinct from the central nervous system, where TGFB reduces nociception. These results provide an explanation for the link between fibrosis and pain in patients with CP. This signaling pathway might be targeted therapeutically to reduce pain in patients with CP. Topics: Animals; Ceruletide; Disease Models, Animal; Fibrosis; Humans; Hyperalgesia; Male; Mice; Mice, Transgenic; Nociceptors; Pain; Pancreas; Pancreatitis, Chronic; Patch-Clamp Techniques; Protein Serine-Threonine Kinases; Rats; Rats, Sprague-Dawley; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Recombinant Proteins; Signal Transduction; Smad3 Protein; Synaptic Potentials; Transforming Growth Factor beta; Trinitrobenzenesulfonic Acid | 2018 |
Inhibition of Jak/STAT signaling reduces the activation of pancreatic stellate cells in vitro and limits caerulein-induced chronic pancreatitis in vivo.
Chronic pancreatitis (CP) is a fibro-inflammatory disease leading to pain, maldigestion, and pancreatic insufficiency. No therapeutic options exist due to a limited understanding of the biology of CP pathology. Recent findings implicate pancreatic stellate cells (PSC) as prominent mediators of inflammatory and fibrotic processes during CP. Here, we utilized primary and immortalized PSC obtained from mice and patients with CP or pancreatic cancer to examine the effect of Jak/STAT and MAPK pathway inhibition in vitro. The well-characterized caerulein model of CP was used to assess the therapeutic efficacy of Jak1/2 inhibition in vivo. Treatment of cultured PSC with the Jak1/2 inhibitor ruxolitinib reduced STAT3 phosphorylation, cell proliferation, and expression of alpha-smooth muscle actin (α-SMA), a marker of PSC activation. Treatment with the MAPK inhibitor, MEK162, had less consistent effects on PSC proliferation and no impact on activation. In the caerulein-induced murine model of CP, administration of ruxolitinib for one week significantly reduced biomarkers of inflammation and fibrosis. These data suggest that the Jak/STAT pathway plays a prominent role in PSC proliferation and activation. In vivo treatment with the Jak1/2 inhibitor ruxolitinib reduced the severity of experimental CP, suggesting that targeting Jak/STAT signaling may represent a promising therapeutic strategy for CP. Topics: Animals; Cell Line; Cell Proliferation; Ceruletide; Cytokines; Disease Models, Animal; Humans; Inflammation Mediators; Janus Kinases; Mice; Pancreatic Stellate Cells; Pancreatitis, Chronic; Protein Kinase Inhibitors; Signal Transduction; STAT Transcription Factors | 2017 |
Adipose Stem Cell Therapy Mitigates Chronic Pancreatitis via Differentiation into Acinar-like Cells in Mice.
The objective of this study was to assess the capacity of adipose-derived mesenchymal stem cells (ASCs) to mitigate disease progression in an experimental chronic pancreatitis mouse model. Chronic pancreatitis (CP) was induced in C57BL/6 mice by repeated ethanol and cerulein injection, and mice were then infused with 4 × 10 Topics: Acinar Cells; Adipose Tissue; Amylases; Animals; Cell Differentiation; Cell Movement; Cell- and Tissue-Based Therapy; Ceruletide; Coculture Techniques; Culture Media, Conditioned; Ethanol; Gene Expression; Genes, Reporter; Green Fluorescent Proteins; Humans; Interleukin-6; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; Tumor Necrosis Factor-alpha | 2017 |
Apelin Regulates Nuclear Factor-κB's Involvement in the Inflammatory Response of Pancreatitis.
Inflammation plays a key role in pancreatitis. Earlier studies from our laboratory showed that experimental pancreatitis activated the pancreatic apelin-APJ axis robustly in mice. Apelin signaling reduced neutrophil invasion and the activation of pancreatic nuclear factor (NF)-κB in mice with experimental pancreatitis.. The aim of this study was to assess whether apelin-induced inhibition of pancreatic NF-κB activation was linked mechanistically to apelin's inhibition of pancreatic inflammatory mediator up-regulation in mice with cerulein-induced chronic pancreatitis (CP). Whether apelin's inhibitory effects were associated with the inhibition of NF-κB binding to the promoter region of IL-1β was examined. The effects of apelin exposure on pancreatic IκB degradation/replenishment and membrane levels of phosphorylated protein kinase C were measured.. Results demonstrated that apelin inhibited the up-regulation of pancreatic tumor necrosis factor α, macrophage inflammatory protein-1 α/β, and IL-1β expression significantly in mice with CP. Chromatin immunoprecipitation assay findings showed that apelin inhibited NF-κB binding to a putative NF-κB binding site in the IL-1β promoter. Apelin exposure reduced the pancreatic membrane levels of phosphorylated protein kinase C-δ and enhanced the replenishment of pancreatic IκB proteins.. Together, these findings indicated that the inhibition of NF-κB activation by apelin was a mechanism behind the reduced pancreatic levels of inflammatory mediators in CP mice exposed to apelin. Topics: Animals; Apelin; Ceruletide; Cytokines; Gene Expression Regulation; Inflammation Mediators; Interleukin-1beta; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Knockout; NF-kappa B; Pancreatitis, Chronic; Promoter Regions, Genetic; Protein Binding; Tumor Necrosis Factor-alpha | 2017 |
Context-Dependent Epigenetic Regulation of Nuclear Factor of Activated T Cells 1 in Pancreatic Plasticity.
The ability of exocrine pancreatic cells to change the cellular phenotype is required for tissue regeneration upon injury, but also contributes to their malignant transformation and tumor progression. We investigated context-dependent signaling and transcription mechanisms that determine pancreatic cell fate decisions toward regeneration and malignancy. In particular, we studied the function and regulation of the inflammatory transcription factor nuclear factor of activated T cells 1 (NFATC1) in pancreatic cell plasticity and tissue adaptation.. We analyzed cell plasticity during pancreatic regeneration and transformation in mice with pancreas-specific expression of a constitutively active form of NFATC1, or depletion of enhancer of zeste 2 homologue 2 (EZH2), in the context of wild-type or constitutively activate Kras, respectively. Acute and chronic pancreatitis were induced by intraperitoneal injection of caerulein. EZH2-dependent regulation of NFATC1 expression was studied in mouse in human pancreatic tissue and cells by immunohistochemistry, immunoblotting, and quantitative reverse transcription polymerase chain reaction. We used genetic and pharmacologic approaches of EZH2 and NFATC1 inhibition to study the consequences of pathway disruption on pancreatic morphology and function. Epigenetic modifications on the NFATC1 gene were investigated by chromatin immunoprecipitation assays.. NFATC1 was rapidly and transiently induced in early adaptation to acinar cell injury in human samples and in mice, where it promoted acinar cell transdifferentiation and blocked proliferation of metaplastic pancreatic cells. However, in late stages of regeneration, Nfatc1 was epigenetically silenced by EZH2-dependent histone methylation, to enable acinar cell redifferentiation and prevent organ atrophy and exocrine insufficiency. In contrast, oncogenic activation of KRAS signaling in pancreatic ductal adenocarcinoma cells reversed the EZH2-dependent effects on the NFATC1 gene and was required for EZH2-mediated transcriptional activation of NFATC1.. In studies of human and mouse pancreatic cells and tissue, we identified context-specific epigenetic regulation of NFATc1 activity as an important mechanism of pancreatic cell plasticity. Inhibitors of EZH2 might therefore interfere with oncogenic activity of NFATC1 and be used in treatment of pancreatic ductal adenocarcinoma. Topics: Acinar Cells; Animals; Carcinoma, Pancreatic Ductal; Cell Plasticity; Cell Proliferation; Cell Transdifferentiation; Cell Transformation, Neoplastic; Ceruletide; Cyclin-Dependent Kinase Inhibitor p16; Enhancer of Zeste Homolog 2 Protein; Gene Expression Regulation; Gene Silencing; Histones; Humans; Methylation; Mice; NFATC Transcription Factors; Pancreas; Pancreatic Neoplasms; Pancreatitis, Chronic; Promoter Regions, Genetic; Proto-Oncogene Proteins p21(ras); Regeneration; Signal Transduction; Transcription, Genetic | 2017 |
Inhibition of Chronic Pancreatitis and Murine Pancreatic Intraepithelial Neoplasia by a Dual Inhibitor of c-RAF and Soluble Epoxide Hydrolase in LSL-KrasG¹²D/Pdx-1-Cre Mice.
Mutation of Kirsten rat sarcoma viral oncogene homolog (KRAS) and chronic pancreatitis are the most common pathogenic events involved in human pancreatic carcinogenesis. In the process of long-standing chronic inflammation, aberrant metabolites of arachidonic acid play a crucial role in promoting carcinogenesis, in which the soluble epoxide hydrolase (sEH), as a pro-inflammatory enzyme, generally inactivates anti-inflammatory epoxyeicosatrienoic acids (EETs). Herein, we determined the effect of our newly-synthesized novel compound trans-4-{4-[3-(4-chloro-3-trifluoromethyl-phenyl)-ureido]-cyclohexyloxy}-pyridine-2-carboxylic acid methylamide (t-CUPM), a dual inhibitor of sEH and RAF1 proto-oncogene serine/threonine kinase (c-RAF), on inhibiting the development of pancreatitis and pancreatic intraepithelial neoplasia (mPanIN) in LSL-Kras(G12D)/Pdx1-Cre mice. The results showed that t-CUPM significantly reduced the severity of chronic pancreatitis, as measured by the extent of acini loss, inflammatory cell infiltration and stromal fibrosis. The progression of low-grade mPanIN I to high-grade mPanIN II/III was significantly suppressed. Inhibition of mutant Kras-transmitted phosphorylation of mitogen-activated protein kinase's kinase/extracellular signal-regulated kinases was demonstrated in pancreatic tissues by western blots. Quantitative real-time polymerase chain reaction analysis revealed that t-CUPM treatment significantly reduced the levels of inflammatory cytokines including tumor necrosis facor-α, monocyte chemoattractant protein-1, as well as vascular adhesion molecule-1, and the levels of Sonic hedgehog and Gli transcription factor (Hedgehog pathway). Analysis of the eicosanoid profile revealed a significant increase of the EETs/dihydroxyeicosatrienoic acids ratio, which further confirmed sEH inhibition by t-CUPM. These results indicate that simultaneous inhibition of sEH and c-RAF by t-CUPM is important in preventing chronic pancreatitis and carcinogenesis. Topics: Animals; Anti-Inflammatory Agents; Anticarcinogenic Agents; Carcinoma in Situ; Ceruletide; Chromatography, Liquid; Disease Models, Animal; Eicosanoids; Enzyme Inhibitors; Epoxide Hydrolases; Genetic Predisposition to Disease; Homeodomain Proteins; Immunohistochemistry; Inflammation Mediators; Integrases; Mice, Transgenic; Mutation; Neoplasm Grading; Niacinamide; Pancreas; Pancreatic Neoplasms; Pancreatitis, Chronic; Phenotype; Phenylurea Compounds; Proto-Oncogene Mas; Proto-Oncogene Proteins p21(ras); Severity of Illness Index; Signal Transduction; Tandem Mass Spectrometry; Trans-Activators | 2016 |
Nucleotide-binding oligomerization domain 1 acts in concert with the cholecystokinin receptor agonist, cerulein, to induce IL-33-dependent chronic pancreatitis.
Nucleotide-binding oligomerization domain 1 (NOD1) fulfills important host-defense functions via its responses to a variety of gut pathogens. Recently, however, we showed that in acute pancreatitis caused by administration of cholecystokinin receptor (CCKR) agonist (cerulein) NOD1 also has a role in inflammation via its responses to gut commensal organisms. In the present study, we explored the long-term outcome of such NOD1 responsiveness in a new model of chronic pancreatitis induced by repeated administration of low doses of cerulein in combination with NOD1 ligand. We found that the development of chronic pancreatitis in this model requires intact NOD1 and type I IFN signaling and that such signaling mediates a macrophage-mediated inflammatory response that supports interleukin (IL)-33 production by acinar cells. The IL-33, in turn, has a necessary role in the induction of IL-13 and TGF-β1, factors causing the fibrotic reaction characteristic of chronic pancreatitis. Interestingly, the Th2 effects of IL-33 were attenuated by the concomitant type I IFN response since the inflammation was marked by clear increases in IFN-γ and TNF-α production but only marginal increases in IL-4 production. These studies establish chronic pancreatitis as an IL-33-dependent inflammation resulting from synergistic interactions between the NOD1 and CCKR signaling pathways. Topics: Acinar Cells; Animals; Ceruletide; Diaminopimelic Acid; Disease Models, Animal; Gene Expression Regulation; Interferon-gamma; Interleukin-13; Interleukin-33; Interleukin-4; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Nod1 Signaling Adaptor Protein; Pancreatitis, Chronic; Receptors, Cholecystokinin; Signal Transduction; Th2 Cells; Transforming Growth Factor beta1; Tumor Necrosis Factor-alpha | 2016 |
The Analgesic Effect of the Mitochondria-Targeted Antioxidant SkQ1 in Pancreatic Inflammation.
Background. Chronic pancreatitis is one of the main risk factors for pancreatic cancer. In acute and chronic pancreatitis, oxidative stress is thought to play a key role. In this respect, the recently described mitochondria-targeted antioxidant SkQ1 effectively scavenges reactive oxygen species at nanomolar concentrations. Therefore, we aimed to characterize the influence of SkQ1 on tissue injury and pain in acute and chronic pancreatitis. Methods. Both acute and chronic pancreatitis were induced in C57BL/6 mice by intraperitoneal cerulein injections and treatment with SkQ1 was carried out by peroral applications. Hyperalgesia was assessed by behavioral observation and measurement of abdominal mechanical sensitivity. Blood serum and pancreatic tissue were harvested for analysis of lipase and histology. Results. SkQ1 did not influence pain, serological, or histological parameters of tissue injury in acute pancreatitis. In chronic pancreatitis, a highly significant reduction of pain-related behavior (p < 0.0001) was evident, but histological grading revealed increased tissue injury in SkQ1-treated animals (p = 0.03). Conclusion. After SkQ1 treatment, tissue injury is not ameliorated in acute pancreatitis and increased in chronic pancreatitis. However, we show an analgesic effect in chronic pancreatitis. Further studies will need to elucidate the risks and benefits of mitochondria-targeted antioxidants as an analgesic. Topics: Acute Disease; Analgesics; Animals; Antioxidants; Behavior, Animal; Biomarkers; Ceruletide; Disease Models, Animal; Female; Hyperalgesia; Lipase; Mice, Inbred C57BL; Mitochondria; Motor Activity; Pain Perception; Pancreas; Pancreatitis; Pancreatitis, Chronic; Plastoquinone; Risk Factors | 2016 |
Cerulein-induced pancreatic fibrosis is modulated by Smad7, the major negative regulator of transforming growth factor-β signaling.
Chronic pancreatitis is the most common disease of the exocrine pancreas, characterized by progressive inflammation, acinar atrophy and fibrosis. Transforming growth factor-β signaling (TGFβ) is the most potent fibrogenic cytokine known, and its increased expression is a common denominator for fibrosis in chronic pancreatitis. Smad7 is induced by the TGFβ superfamily members as an intracellular inhibitory feedback antagonizing TGFβ signaling. To investigate the functional role of Smad7 in vivo, we induced chronic pancreatitis by repeated administration of cerulein in mice that are deficient in exon-I of Smad7. The response to chronic pancreatitis induction was significantly more severe in Smad7 mutant mice as indicated by a stronger accumulation of extracellular matrix, increased levels of inflammatory cells and an elevated number of mesenchymal cells/myofibroblasts in Smad7 mutant pancreata. Taken together, we conclude that lack of a functional Smad7 gene results in more severe damage in chronic pancreatitis. Therefore, Smad7 could be envisaged as a promising target in antifibrotic therapy of the pancreas. Topics: Animals; Ceruletide; Exons; Extracellular Matrix; Female; Fibrosis; Male; Mice; Mice, Knockout; Mice, Mutant Strains; Myofibroblasts; Pancreas; Pancreatitis, Chronic; Signal Transduction; Smad7 Protein; Transforming Growth Factor beta | 2016 |
Aryl Hydrocarbon Receptor Ligands in Cigarette Smoke Induce Production of Interleukin-22 to Promote Pancreatic Fibrosis in Models of Chronic Pancreatitis.
Cigarette smoke has been identified as an independent risk factor for chronic pancreatitis (CP). Little is known about the mechanisms by which smoking promotes development of CP. We assessed the effects of aryl hydrocarbon receptor (AhR) ligands found in cigarette smoke on immune cell activation in humans and pancreatic fibrosis in animal models of CP.. Mice given AhR agonists developed more severe pancreatic fibrosis (based on decreased pancreas size, histology, and increased expression of fibrosis-associated genes) than mice not given agonists after caerulein injection. In mice given saline instead of caerulein, AhR ligands did not induce fibrosis. Pancreatic T cells from mice given AhR agonists and caerulein were activated and expressed IL22, but not IL17 or interferon gamma. Human T cells exposed to AhR agonists up-regulated expression of IL22. In mice given anti-IL22, pancreatic fibrosis did not progress, whereas mice given recombinant IL22 had a smaller pancreas and increased fibrosis. Pancreatic stellate cells isolated from mouse and human pancreata expressed the IL22 receptor IL22RA1. Incubation of the pancreatic stellate cells with IL22 induced their expression of the extracellular matrix genes fibronectin 1 and collagen type I α1 chain, but not α2 smooth muscle actin or transforming growth factor-β. Serum samples from smokers had significantly higher levels of IL22 than those from nonsmokers.. AhR ligands found in cigarette smoke increase the severity of pancreatic fibrosis in mouse models of pancreatitis via up-regulation of IL22. This pathway might be targeted for treatment of CP and serve as a biomarker of disease. Topics: Actins; Animals; Antibodies; Benzo(a)pyrene; CD4-Positive T-Lymphocytes; Cells, Cultured; Ceruletide; Collagen Type I; Collagen Type I, alpha 1 Chain; Disease Models, Animal; Fibronectins; Fibrosis; Gene Expression; Humans; Interferon-gamma; Interleukin-17; Interleukin-22; Interleukins; Ligands; Lymphocyte Activation; Mice; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Polychlorinated Dibenzodioxins; Receptors, Aryl Hydrocarbon; Receptors, Interleukin; Smoke; Smoking; Tobacco Products; Transforming Growth Factor beta | 2016 |
The MET Receptor Tyrosine Kinase Confers Repair of Murine Pancreatic Acinar Cells following Acute and Chronic Injury.
Acinar cells represent the primary target in necroinflammatory diseases of the pancreas, including pancreatitis. The signaling pathways guiding acinar cell repair and regeneration following injury remain poorly understood. The purpose of this study was to determine the importance of Hepatocyte Growth Factor Receptor/MET signaling as an intrinsic repair mechanism for acinar cells following acute damage and chronic alcohol-associated injury. Here, we generated mice with targeted deletion of MET in adult acinar cells (MET-/-). Acute and repetitive pancreatic injury was induced in MET-/- and control mice with cerulein, and chronic injury by feeding mice Lieber-DeCarli diets containing alcohol with or without enhancement of repetitive pancreatic injury. We examined the exocrine pancreas of these mice histologically for acinar death, edema, inflammation and collagen deposition and changes in the transcriptional program. We show that MET expression is relatively low in normal adult pancreas. However, MET levels were elevated in ductal and acinar cells in human pancreatitis specimens, consistent with a role for MET in an adaptive repair mechanism. We report that genetic deletion of MET in adult murine acinar cells was linked to increased acinar cell death, chronic inflammation and delayed recovery (regeneration) of pancreatic exocrine tissue. Notably, increased pancreatic collagen deposition was detected in MET knockout mice following repetitive injury as well alcohol-associated injury. Finally, we identified specific alterations of the pancreatic transcriptome associated with MET signaling during injury, involved in tissue repair, inflammation and endoplasmic reticulum stress. Together, these data demonstrate the importance of MET signaling for acinar repair and regeneration, a novel finding that could attenuate the symptomology of pancreatic injury. Topics: Acinar Cells; Acute Disease; Alcohol Drinking; Animals; Ceruletide; Chronic Disease; Collagen; Disease Models, Animal; Gene Deletion; Humans; Inflammation; Macrophages; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; Proto-Oncogene Proteins c-met; Regeneration; Wound Healing | 2016 |
CXCR2 inhibition suppresses acute and chronic pancreatic inflammation.
Pancreatitis is a significant clinical problem and the lack of effective therapeutic options means that treatment is often palliative rather than curative. A deeper understanding of the pathogenesis of both acute and chronic pancreatitis is necessary to develop new therapies. Pathological changes in pancreatitis are dependent on innate immune cell recruitment to the site of initial tissue damage, and on the coordination of downstream inflammatory pathways. The chemokine receptor CXCR2 drives neutrophil recruitment during inflammation, and to investigate its role in pancreatic inflammation, we induced acute and chronic pancreatitis in wild-type and Cxcr2(-/-) mice. Strikingly, Cxcr2(-/-) mice were strongly protected from tissue damage in models of acute pancreatitis, and this could be recapitulated by neutrophil depletion or by the specific deletion of Cxcr2 from myeloid cells. The pancreata of Cxcr2(-/-) mice were also substantially protected from damage during chronic pancreatitis. Neutrophil depletion was less effective in this model, suggesting that CXCR2 on non-neutrophils contributes to the development of chronic pancreatitis. Importantly, pharmacological inhibition of CXCR2 in wild-type mice replicated the protection seen in Cxcr2(-/-) mice in acute and chronic models of pancreatitis. Moreover, acute pancreatic inflammation was reversible by inhibition of CXCR2. Thus, CXCR2 is critically involved in the development of acute and chronic pancreatitis in mice, and its inhibition or loss protects against pancreatic damage. CXCR2 may therefore be a viable therapeutic target in the treatment of pancreatitis. Topics: Acute Disease; Animals; Anti-Inflammatory Agents; Ceruletide; Cytoprotection; Disease Models, Animal; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Neutrophils; Pancreas; Pancreatitis; Pancreatitis, Chronic; Peptides; Receptors, Interleukin-8B; Signal Transduction; Time Factors | 2015 |
Complement Component 5 Mediates Development of Fibrosis, via Activation of Stellate Cells, in 2 Mouse Models of Chronic Pancreatitis.
Little is known about the pathogenic mechanisms of chronic pancreatitis. We investigated the roles of complement component 5 (C5) in pancreatic fibrogenesis in mice and patients.. Chronic pancreatitis was induced by ligation of the midpancreatic duct, followed by a single supramaximal intraperitoneal injection of cerulein, in C57Bl6 (control) and C5-deficient mice. Some mice were given injections of 2 different antagonists of the receptor for C5a over 21 days. In a separate model, mice were given injections of cerulein for 10 weeks to induce chronic pancreatitis. Direct effects of C5 were studied in cultured primary cells. We performed genotype analysis for the single-nucleotide polymorphisms rs 17611 and rs 2300929 in C5 in patients with pancreatitis and healthy individuals (controls). Blood cells from 976 subjects were analyzed by transcriptional profiling.. During the initial phase of pancreatitis, levels of pancreatic damage were similar between C5-deficient and control mice. During later stages of pancreatitis, C5-deficient mice and mice given injections of C5a-receptor antagonists developed significantly less pancreatic fibrosis than control mice. Primary pancreatic stellate cells were activated in vitro by C5a. There were no differences in the rs 2300929 SNP between subjects with or without pancreatitis, but the minor allele rs17611 was associated with a significant increase in levels of C5 in whole blood.. In mice, loss of C5 or injection of a C5a-receptor antagonist significantly reduced the level of fibrosis of chronic pancreatitis, but this was not a consequence of milder disease in early stages of pancreatitis. C5 might be a therapeutic target for chronic pancreatitis. Topics: Aniline Compounds; Animals; Case-Control Studies; Ceruletide; Complement C5; Disease Models, Animal; Fibrosis; Genetic Predisposition to Disease; Ligation; Mice, Inbred C57BL; Mice, Knockout; Pancreatic Ducts; Pancreatic Stellate Cells; Pancreatitis, Chronic; Phenotype; Polymorphism, Single Nucleotide; Receptor, Anaphylatoxin C5a; Tetrahydronaphthalenes; Time Factors | 2015 |
Gremlin is a key pro-fibrogenic factor in chronic pancreatitis.
The current study aims to identify the pro-fibrogenic role of Gremlin, an endogenous antagonist of bone morphogenetic proteins (BMPs) in chronic pancreatitis (CP). CP is a highly debilitating disease characterized by progressive pancreatic inflammation and fibrosis that ultimately leads to exocrine and endocrine dysfunction. While transforming growth factor (TGF)-β is a known key pro-fibrogenic factor in CP, the TGF-β superfamily member BMPs exert an anti-fibrogenic function in CP as reported by our group recently. To investigate how BMP signaling is regulated in CP by BMP antagonists, the mouse CP model induced by cerulein was used. During CP induction, TGF-β1 messenger RNA (mRNA) increased 156-fold in 2 weeks, a BMP antagonist Gremlin 1 (Grem1) mRNA levels increased 145-fold at 3 weeks, and increases in Grem1 protein levels correlated with increases in collagen deposition. Increased Grem1 was also observed in human CP pancreata compared to normal. Grem1 knockout in Grem1 (+/-) mice revealed a 33.2 % reduction in pancreatic fibrosis in CP compared to wild-type littermates. In vitro in isolated pancreatic stellate cells, TGF-β induced Grem1 expression. Addition of the recombinant mouse Grem1 protein blocked BMP2-induced Smad1/5 phosphorylation and abolished BMP2's suppression effects on TGF-β-induced collagen expression. Evidences presented herein demonstrate that Grem1, induced by TGF-β, is pro-fibrogenic by antagonizing BMP activity in CP.. • Gremlin is upregulated in human chronic pancreatitis and a mouse CP model in vivo. • Deficiency of Grem1 in mice attenuates pancreatic fibrosis under CP induction in vivo. • TGF-β induces Gremlin mRNA and protein expression in pancreatic stellate cells in vitro. • Gremlin blocks BMP2 signaling and function in pancreatic stellate cells in vitro. • This study discloses a pro-fibrogenic role of Gremlin by antagonizing BMP activity in chronic pancreatitis. Topics: Animals; Bone Morphogenetic Protein 2; Cells, Cultured; Ceruletide; Collagen; Female; Fibrosis; Humans; Intercellular Signaling Peptides and Proteins; Male; Mice, Transgenic; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; RNA, Messenger; Transforming Growth Factor beta1 | 2015 |
Characterization of Mouse Models of Early Pancreatic Lesions Induced by Alcohol and Chronic Pancreatitis.
We describe the first mouse model of pancreatic intraepithelial neoplasia (PanIN) lesions induced by alcohol in the presence and absence of chronic pancreatitis.. Pdx1-Cre;LSL-K-ras mice were exposed to Lieber-DeCarli alcohol diet for 6 weeks with cerulein injections. The PanIN lesions and markers of fibrosis, inflammation, histone deacetylation, epithelial-to-mesenchymal transition (EMT), and cancer stemness were measured by immunohistochemistry and Western.. Exposure of Pdx1-Cre;LSL-K-ras mice to an alcohol diet significantly stimulated fibrosis and slightly but not significantly increased the level of PanIN lesions associated with an increase in tumor-promoting M2 macrophages. Importantly, the alcohol diet did not increase activation of stellate cells. Alcohol diet and cerulein injections resulted in synergistic and additive effects on PanIN lesion and M2 macrophage phenotype induction, respectively. Cerulein pancreatitis caused stellate cell activation, EMT, and cancer stemness in the pancreas. Pancreatitis caused histone deacetylation, which was promoted by the alcohol diet. Pancreatitis increased EMT and cancer stemness markers, which were not further affected by the alcohol diet.. The results suggest that alcohol has independent effects on promotion of PDAC associated with fibrosis formed through a stellate cell-independent mechanism and that it further promotes early PDAC and M2 macrophage induction in the context of chronic pancreatitis. Topics: Acetylation; Acute Disease; Animals; Carcinoma in Situ; Cell Transformation, Neoplastic; Ceruletide; Disease Models, Animal; Epithelial-Mesenchymal Transition; Ethanol; Fibrosis; Histones; Macrophages; Mice, Transgenic; Neoplastic Stem Cells; Pancreas; Pancreatic Neoplasms; Pancreatic Stellate Cells; Pancreatitis; Pancreatitis, Alcoholic; Pancreatitis, Chronic; Time Factors | 2015 |
Induction of chronic pancreatitis by pancreatic duct ligation activates BMP2, apelin, and PTHrP expression in mice.
Chronic pancreatitis (CP) is a devastating disease with no treatments. Experimental models have been developed to reproduce the parenchyma and inflammatory responses typical of human CP. For the present study, one objective was to assess and compare the effects of pancreatic duct ligation (PDL) to those of repetitive cerulein (Cer)-induced CP in mice on pancreatic production of bone morphogenetic protein-2 (BMP2), apelin, and parathyroid hormone-related protein (PTHrP). A second objective was to determine the extent of cross talk among pancreatic BMP2, apelin, and PTHrP signaling systems. We focused on BMP2, apelin, and PTHrP since these factors regulate the inflammation-fibrosis cascade during pancreatitis. Findings showed that PDL- and Cer-induced CP resulted in significant elevations in expression and peptide/protein levels of pancreatic BMP2, apelin, and PTHrP. In vivo mouse and in vitro pancreatic cell culture experiments demonstrated that BMP2 stimulated pancreatic apelin expression whereas apelin expression was inhibited by PTHrP exposure. Apelin or BMP2 exposure inhibited PTHrP expression, and PTHrP stimulated upregulation of gremlin, an endogenous inhibitor of BMP2 activity. Transforming growth factor-β (TGF-β) stimulated PTHrP expression. Together, findings demonstrated that PDL- and Cer-induced CP resulted in increased production of the pancreatic BMP2, apelin, and PTHrP signaling systems and that significant cross talk occurred among pancreatic BMP2, apelin, and PTHrP. These results together with previous findings imply that these factors interact via a pancreatic network to regulate the inflammation-fibrosis cascade during CP. More importantly, this network communicated with TGF-β, a key effector of pancreatic pathophysiology. This novel network may be amenable to pharmacologic manipulations during CP in humans. Topics: Adipokines; Animals; Apelin; Blotting, Western; Bone Morphogenetic Protein 2; Cell Culture Techniques; Ceruletide; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Humans; Intercellular Signaling Peptides and Proteins; Ligation; Male; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Pancreatic Ducts; Pancreatitis, Chronic; Parathyroid Hormone-Related Protein; Real-Time Polymerase Chain Reaction; Signal Transduction | 2015 |
Retinoic Acid Ameliorates Pancreatic Fibrosis and Inhibits the Activation of Pancreatic Stellate Cells in Mice with Experimental Chronic Pancreatitis via Suppressing the Wnt/β-Catenin Signaling Pathway.
Pancreatic fibrosis, a prominent feature of chronic pancreatitis (CP), induces persistent and permanent damage in the pancreas. Pancreatic stellate cells (PSCs) provide a major source of extracellular matrix (ECM) deposition during pancreatic injury, and persistent activation of PSCs plays a vital role in the progression of pancreatic fibrosis. Retinoic acid (RA), a retinoid, has a broad range of biological functions, including regulation of cell differentiation and proliferation, attenuating progressive fibrosis of multiple organs. In the present study, we investigated the effects of RA on fibrosis in experimental CP and cultured PSCs. CP was induced in mice by repetitive cerulein injection in vivo, and mouse PSCs were isolated and activated in vitro. Suppression of pancreatic fibrosis upon administration of RA was confirmed based on reduction of histological damage, α-smooth muscle actin (α-SMA) expression and mRNA levels of β-catenin, platelet-derived growth factor (PDGF)-Rβ transforming growth factor (TGF)-βRII and collagen 1α1 in vivo. Wnt 2 and β-catenin protein levels were markedly down-regulated, while Axin 2 expression level was up-regulated in the presence of RA, both in vivo and in vitro. Nuclear translation of β-catenin was significantly decreased following RA treatment, compared with cerulein-induced CP in mice and activated PSCs. Furthermore, RA induced significant PSC apoptosis, inhibited proliferation, suppressed TCF/LEF-dependent transcriptional activity and ECM production of PSC via down-regulation of TGFβRII, PDGFRβ and collagen 1α1 in vitro. These results indicate a critical role of the Wnt/β-catenin signaling pathway in RA-induced effects on CP and PSC regulation and support the potential of RA as a suppressor of pancreatic fibrosis in mice. Topics: Actins; Active Transport, Cell Nucleus; Animals; Apoptosis; Axin Protein; Cells, Cultured; Ceruletide; Collagen Type I; Disease Progression; Drug Evaluation, Preclinical; Fibrosis; Gene Expression Regulation; Lipase; Male; Mice; Mice, Inbred BALB C; Organ Size; Pancreas; Pancreatic alpha-Amylases; Pancreatic Stellate Cells; Pancreatitis, Chronic; Proteoglycans; Random Allocation; Receptor, Platelet-Derived Growth Factor beta; Receptors, Transforming Growth Factor beta; RNA, Messenger; Tretinoin; Wnt Signaling Pathway | 2015 |
Regulation of pancreatic inflammation by connective tissue growth factor (CTGF/CCN2).
Pancreatitis is caused by long-term heavy alcohol consumption, which results in injury and death of pancreatic acinar cells (PAC). The PAC play a pivotal role in mediating early inflammatory responses but the underlying mechanisms remain poorly understood. Treatment of C57BL/6 mice with ethanol and cerulein resulted in increased staining for acinar interleukin- 1b (IL-1b), chemokine (C-C motif) ligand 3 (CCL3), or connective tissue growth factor (CTGF/CCN2) by Day 16 and this was associated with increased infiltration of F4/80-positive macrophages and increased expression of pancreatic CTGF/CCN2 mRNA. Compared with wild-type Swiss Webster mice, ethanol treatment of pan-green fluorescent protein (GFP)-CTGF/CCN2 transgenic mice caused enhanced acinar staining for GFP or CTGF/CCN2 and a significant increase in pancreatic infiltration of F4/80-positive macrophages or NIMP-R14-positive neutrophils. Treatment of primary mouse PAC or the rat AR42J PAC line with ethanol or CTGF/CCN2 resulted in enhanced expression of IL-1b or CCL3. Conditioned medium from CTGF/CCN2-treated AR42J cells induced chemotaxis in NR8383 macrophages and this response was abrogated in a dose dependent manner by addition of BX471, an inhibitor of chemokine (C-C motif) receptor 1. These results reveal that acinar CTGF/CCN2 plays a novel role in alcohol-induced inflammatory processes in the pancreas by increasing infiltration of macrophages and neutrophils and increasing acinar production of inflammatory mediators such as IL-1b or CCL3. The early production of CTGF/CCN2 by PAC to drive inflammation is distinct from its previously reported production by pancreatic stellate cells to drive fibrosis at later stages of pancreatic injury. Topics: Acinar Cells; Animals; Antigens, Differentiation; Biomarkers; Cell Line; Ceruletide; Chemokine CCL3; Chemotaxis; Connective Tissue Growth Factor; Culture Media, Conditioned; Disease Models, Animal; Ethanol; Green Fluorescent Proteins; Inflammation Mediators; Interleukin-1beta; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neutrophils; Pancreas, Exocrine; Pancreatitis, Alcoholic; Pancreatitis, Chronic; Primary Cell Culture; Rats; Receptors, CCR1; RNA Interference; RNA, Messenger; Signal Transduction; Time Factors; Transfection; Up-Regulation | 2014 |
Spatiotemporal proteomic analyses during pancreas cancer progression identifies serine/threonine stress kinase 4 (STK4) as a novel candidate biomarker for early stage disease.
Pancreas cancer, or pancreatic ductal adenocarcinoma, is the deadliest of solid tumors, with a five-year survival rate of <5%. Detection of resectable disease improves survival rates, but access to tissue and other biospecimens that could be used to develop early detection markers is confounded by the insidious nature of pancreas cancer. Mouse models that accurately recapitulate the human condition allow disease tracking from inception to invasion and can therefore be useful for studying early disease stages in which surgical resection is possible. Using a highly faithful mouse model of pancreas cancer in conjunction with a high-density antibody microarray containing ∼2500 antibodies, we interrogated the pancreatic tissue proteome at preinvasive and invasive stages of disease. The goal was to discover early stage tissue markers of pancreas cancer and follow them through histologically defined stages of disease using cohorts of mice lacking overt clinical signs and symptoms and those with end-stage metastatic disease, respectively. A panel of seven up-regulated proteins distinguishing pancreas cancer from normal pancreas was validated, and their levels were assessed in tissues collected at preinvasive, early invasive, and moribund stages of disease. Six of the seven markers also differentiated pancreas cancer from an experimental model of chronic pancreatitis. The levels of serine/threonine stress kinase 4 (STK4) increased between preinvasive and invasive stages, suggesting its potential as a tissue biomarker, and perhaps its involvement in progression from precursor pancreatic intraepithelial neoplasia to pancreatic ductal adenocarcinoma. Immunohistochemistry of STK4 at different stages of disease revealed a dynamic expression pattern further implicating it in early tumorigenic events. Immunohistochemistry of a panel of human pancreas cancers confirmed that STK4 levels were increased in tumor epithelia relative to normal tissue. Overall, this integrated approach yielded several tissue markers that could serve as signatures of disease stage, including early (resectable), and therefore clinically meaningful, stages. Topics: Animals; Antibodies; Biomarkers, Tumor; Carcinoma, Pancreatic Ductal; Ceruletide; Diagnosis, Differential; Disease Models, Animal; Disease Progression; Early Diagnosis; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Mice; Molecular Sequence Annotation; Neoplasm Proteins; Pancreatic Neoplasms; Pancreatitis, Chronic; Protein Array Analysis; Protein Serine-Threonine Kinases; Proteome; Signal Transduction; Time Factors | 2014 |
BMP2 inhibits TGF-β-induced pancreatic stellate cell activation and extracellular matrix formation.
Activation of pancreatic stellate cells (PSCs) by transforming growth factor (TGF)-β is the key step in the development of pancreatic fibrosis, a common pathological feature of chronic pancreatitis (CP). Bone morphogenetic proteins (BMPs), members of the TGF-β superfamily, have anti-fibrogenic functions, in contrast to TGF-β, in the kidney, lung, and liver. However, it is not known whether BMPs have an anti-fibrogenic role in the pancreas. The current study was designed to investigate the potential anti-fibrogenic role of BMPs in the pancreas using an in vivo CP model and an in vitro PSC model. CP was induced by repetitive intraperitoneal injections of cerulein in adult Swiss Webster mice. The control mice received saline injections. Compared with the control, cerulein injections induced a time-dependent increase in acinar injury and progression of fibrosis and a steady increase in inflammation. Cerulein injections also induced increases of the extracellular matrix (ECM) protein fibronectin and of α-smooth muscle actin (α-SMA)-positive stellate cells (PSCs). The mice receiving cerulein injections showed increased BMP2 protein levels and phosphorylated Smad1 levels up to 4 wk and then declined at 8 wk to similar levels as the control. In vitro, the isolated mouse and human PSCs were cultured and pretreated with BMP2 followed by TGF-β treatment. BMP2 pretreatment inhibited TGF-β-induced α-SMA, fibronectin, and collagen type Ia expression. Knocking down Smad1 with small-interfering RNA reversed the inhibitory effect of BMP2 on TGF-β-induced α-SMA and fibronectin expression. Thus, BMP2 opposes the fibrogenic function of TGF-β in PSCs through the Smad1 signaling pathway. Topics: Actins; Animals; Bone Morphogenetic Protein 2; Ceruletide; Extracellular Matrix; Female; Fibronectins; Fibrosis; Humans; Mice; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Signal Transduction; Smad1 Protein; Transforming Growth Factor beta | 2013 |
Risk factors for pancreatic ductal adenocarcinoma specifically stimulate pancreatic duct glands in mice.
Diabetes mellitus type 2 and chronic pancreatitis are regarded as risk factors for pancreatic cancer. Pancreatic duct glands (PDGs) were recently described as a new compartment of the major duct in humans and mice. To evaluate the influence of diabetes and chronic pancreatitis on PDGs, cerulein was injected i.p., repetitively over 10 weeks, in mice exhibiting obesity and a type 2 diabetes-like syndrome (B6.V-Lep(ob/ob)) and in lean littermates. By using 5-bromo-2'-deoxyuridine (BrdU), a label-retaining cell population was characterized in PDGs. Cerulein administration led to more BrdU(+) cells in PDGs of obese mice compared with lean mice. The observed increase was specific to PDGs, because BrdU incorporation in cells of the pancreatic duct was not increased. In addition, the expression of distinct tumor markers in PDGs was characterized by Muc5ac, S100P, regenerating islet-derived 3β, 14-3-3 σ, and prostate stem cell antigen immunochemistry. Type 2 diabetes-like syndrome, accompanied by chronic pancreatitis, enhanced nuclear localization of S100P. Both risk factors for pancreatic cancer also induced the production of Muc5ac and the nuclear localization of S100P [corrected]. These results demonstrate that diabetes and chronic pancreatitis jointly enhance BrdU incorporation and production of pancreatic cancer-specific proteins in PDGs. The observed alterations suggest that pancreatic tumors might originate from the newly discovered histomorphological structures, called PDGs, which could represent a target for future anticancer therapies. Topics: Animals; Bromodeoxyuridine; Carcinoma, Pancreatic Ductal; Ceruletide; Diabetes Mellitus, Type 2; Humans; Male; Metaplasia; Mice; Mice, Obese; Mucins; Neoplasm Proteins; Pancreatic Ducts; Pancreatic Neoplasms; Pancreatitis, Chronic; Risk Factors | 2013 |
CCR2 knockout exacerbates cerulein-induced chronic pancreatitis with hyperglycemia via decreased GLP-1 receptor expression and insulin secretion.
Glucagon-like peptide-1 (GLP-1) promotes insulin release; however, the relationship between the GLP-1 signal and chronic pancreatitis is not well understood. Here we focus on chemokine (C-C motif) ligand 2 (CCL2) and its receptor (CCR2) axis, which regulates various immune cells, including macrophages, to clarify the mechanism of GLP-1-mediated insulin secretion in chronic pancreatitis in mice. One and multiple series of repetitive cerulein administrations were used to induce acute and chronic cerulein pancreatitis, respectively. Acute cerulein-administered CCR2-knockout (KO) mice showed suppressed infiltration of CD11b(+)Gr-1(low) macrophages and pancreatic inflammation and significantly upregulated insulin secretion compared with paired wild-type (WT) mice. However, chronic cerulein-administered CCR2-KO mice showed significantly increased infiltration of CD11b(+)/Gr-1(-) and CD11b(+)/Gr-1(high) cells, but not CD11b(+)/Gr-1(low) cells, in pancreas with severe inflammation and significantly decreased insulin secretion compared with their WT counterparts. Furthermore, although serum GLP-1 levels in chronic cerulein-administered WT and CCR2-KO mice were comparably upregulated after cerulein administrations, GLP-1 receptor levels in pancreases of chronic cerulein-administered CCR2-KO mice were significantly lower than in paired WT mice. Nevertheless, a significantly higher hyperglycemia level in chronic cerulein-administered CCR2-KO mice was markedly restored by treatment with a GLP-1 analog to a level comparable to the paired WT mice. Collectively, the CCR2/CCL2 axis-mediated CD11b(+)-cell migration to the pancreas is critically involved in chronic pancreatitis-mediated hyperglycemia through the modulation of GLP-1 receptor expression and insulin secretion. Topics: Acute Disease; Animals; CD11b Antigen; Ceruletide; Chronic Disease; Disease Models, Animal; Female; Glucagon-Like Peptide-1 Receptor; Glucose Intolerance; Hyperglycemia; Insulin; Insulin Secretion; Islets of Langerhans; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Pancreatitis, Chronic; Receptors, CCR2; Receptors, Glucagon | 2013 |
TRPV1 and TRPA1 antagonists prevent the transition of acute to chronic inflammation and pain in chronic pancreatitis.
Visceral afferents expressing transient receptor potential (TRP) channels TRPV1 and TRPA1 are thought to be required for neurogenic inflammation and development of inflammatory hyperalgesia. Using a mouse model of chronic pancreatitis (CP) produced by repeated episodes (twice weekly) of caerulein-induced AP (AP), we studied the involvement of these TRP channels in pancreatic inflammation and pain-related behaviors. Antagonists of the two TRP channels were administered at different times to block the neurogenic component of AP. Six bouts of AP (over 3 wks) increased pancreatic inflammation and pain-related behaviors, produced fibrosis and sprouting of pancreatic nerve fibers, and increased TRPV1 and TRPA1 gene transcripts and a nociceptive marker, pERK, in pancreas afferent somata. Treatment with TRP antagonists, when initiated before week 3, decreased pancreatic inflammation and pain-related behaviors and also blocked the development of histopathological changes in the pancreas and upregulation of TRPV1, TRPA1, and pERK in pancreatic afferents. Continued treatment with TRP antagonists blocked the development of CP and pain behaviors even when mice were challenged with seven more weeks of twice weekly caerulein. When started after week 3, however, treatment with TRP antagonists was ineffective in blocking the transition from AP to CP and the emergence of pain behaviors. These results suggest: (1) an important role for neurogenic inflammation in pancreatitis and pain-related behaviors, (2) that there is a transition from AP to CP, after which TRP channel antagonism is ineffective, and thus (3) that early intervention with TRP channel antagonists may attenuate the transition to and development of CP effectively. Topics: Amidines; Analgesics, Opioid; Analysis of Variance; Animals; Antigens, Differentiation; Calcitonin Gene-Related Peptide; Calcium; Ceruletide; Disease Models, Animal; Disease Progression; Exploratory Behavior; Extracellular Signal-Regulated MAP Kinases; Ganglia, Spinal; Gene Expression Regulation; Injections, Intraperitoneal; Male; Mice; Mice, Inbred C57BL; Monocytes; Morphine; Neutrophil Infiltration; Nodose Ganglion; Oximes; Pain; Pain Measurement; Pancreas; Pancreatitis, Chronic; Peroxidase; Pyridines; RNA, Messenger; Sensory Receptor Cells; Time Factors; Transient Receptor Potential Channels; TRPA1 Cation Channel; TRPV Cation Channels | 2013 |
Snail cooperates with KrasG12D to promote pancreatic fibrosis.
Patients with pancreatic cancer, which is characterized by an extensive collagen-rich fibrotic reaction, often present with metastases. A critical step in cancer metastasis is epithelial-to-mesenchymal transition (EMT), which can be orchestrated by the Snail family of transcription factors. To understand the role of Snail (SNAI1) in pancreatic cancer development, we generated transgenic mice expressing Snail in the pancreas. Because chronic pancreatitis can contribute to pancreatic cancer development, Snail-expressing mice were treated with cerulein to induce pancreatitis. Although significant tissue injury was observed, a minimal difference in pancreatitis was seen between control and Snail-expressing mice. However, because Kras mutation is necessary for tumor development in mouse models of pancreatic cancer, we generated mice expressing both mutant Kras(G12D) and Snail (Kras(+)/Snail(+)). Compared with control mice (Kras(+)/Snai(-)), Kras(+)/Snail(+) mice developed acinar ectasia and more advanced acinar-to-ductal metaplasia. The Kras(+)/Snail(+) mice exhibited increased fibrosis, increased phosphorylated Smad2, increased TGF-β2 expression, and activation of pancreatic stellate cells. To further understand the mechanism by which Snail promoted fibrosis, we established an in vitro model to examine the effect of Snail expression in pancreatic cancer cells on stellate cell collagen production. Snail expression in pancreatic cancer cells increased TGF-β2 levels, and conditioned media from Snail-expressing pancreatic cancer cells increased collagen production by stellate cells. Additionally, inhibiting TGF-β signaling in stellate cells attenuated the conditioned media-induced collagen production by stellate cells. Together, these results suggest that Snail contributes to pancreatic tumor development by promoting fibrotic reaction through increased TGF-β signaling.. Expression of the EMT regulator Snail in the context of mutant Kras provides new insight into pancreatic cancer progression. Topics: Animals; Cell Proliferation; Ceruletide; Collagen; Epithelial-Mesenchymal Transition; Fibrosis; Mice; Mice, Transgenic; Pancreas; Pancreatic Neoplasms; Pancreatic Stellate Cells; Pancreatitis, Chronic; Proto-Oncogene Proteins p21(ras); Signal Transduction; Smad2 Protein; Snail Family Transcription Factors; Transcription Factors; Transforming Growth Factor beta2; Tumor Cells, Cultured | 2013 |
Differences in the degree of cerulein-induced chronic pancreatitis in C57BL/6 mouse substrains lead to new insights in identification of potential risk factors in the development of chronic pancreatitis.
A frequently used experimental model of chronic pancreatitis (CP) recapitulating human disease is repeated injection of cerulein into mice. C57BL/6 is the most commonly used inbred mouse strain for biomedical research, but widespread demand has led to generation of several substrains with subtly different phenotypes. In this study, two common substrains, C57BL/6J and C57BL/6NHsd, exhibited different degrees of CP, with C57BL/6J being more susceptible to repetitive cerulein-induced CP as assessed by pancreatic atrophy, pancreatic morphological changes, and fibrosis. We hypothesized that the deficiency of nicotinamide nucleotide transhydrogenase (NNT) protein in C57BL/6J is responsible for the more severe C57BL/6J phenotype but the parameters of CP in NNT-expressing transgenic mice generated on a C57BL6/J background do not differ with those of wild-type C57BL/6J. The highly similar genetic backgrounds but different CP phenotypes of these two substrains presents a unique opportunity to discover genes important in pathogenesis of CP. We therefore performed whole mouse genome Affymetrix microarray analysis of pancreatic gene expression of C57BL/6J and C57BL/6NHsd before and after induction of CP. Genes with differentially regulated expression between the two substrains that might be candidates in CP progression included Mmp7, Pcolce2, Itih4, Wdfy1, and Vtn. We also identified several genes associated with development of CP in both substrains, including RIKEN cDNA 1810009J06 gene (trypsinogen 5), Ccl8, and Ccl6. Topics: Animals; Cell Separation; Ceruletide; Chemokine CCL8; Chemokines, CC; Collagen; Disease Progression; Fibrosis; Gene Expression Profiling; Gene Expression Regulation; Genetic Association Studies; Humans; Mice; Mice, Inbred C57BL; NADP Transhydrogenases; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Risk Factors; RNA, Messenger; Trypsinogen | 2013 |
Treatment of pancreatic fibrosis with siRNA against a collagen-specific chaperone in vitamin A-coupled liposomes.
Fibrosis associated with chronic pancreatitis is an irreversible lesion that can disrupt pancreatic exocrine and endocrine function. Currently, there are no approved treatments for this disease. We previously showed that siRNA against collagen-specific chaperone protein gp46, encapsulated in vitamin A-coupled liposomes (VA-lip-siRNAgp46), resolved fibrosis in a model of liver cirrhosis. This treatment was investigated for pancreatic fibrosis induced by dibutyltin dichloride (DBTC) and cerulein in rats.. Specific uptake of VA-lip-siRNAgp46, conjugated with 6'-carboxyfluorescein (FAM) by activated pancreatic stellate cells (aPSCs), was analysed by fluorescence activated cell sorting (FACS). Intracellular distribution of VA-lip-siRNAgp46-FAM was examined by fluorescent microscopy. Suppression of gp46 expression by VA-lip-siRNAgp46 was assessed by immunoblotting. Collagen synthesis in aPSCs was assayed by dye-binding. Specific delivery of VA-lip-siRNAgp46 to aPSCs in DBTC rats was verified following intravenous VA-lip-siRNA-FAM and (3)H-VA-lip-siRNAgp46. The effect of VA-lip-siRNA on pancreatic histology in DBTC- and cerulein-treated rats was determined by Azan-Mallory staining and hydroxyproline content.. FACS analysis revealed specific uptake of VA-lip-siRNAgp46-FAM through the retinol binding protein receptor by aPSCs in vitro. Immunoblotting and collagen assay verified knockdown of gp46 and suppression of collagen secretion, respectively, by aPSCs after transduction of VA-lip-siRNAgp46. Specific delivery of VA-lip-siRNAgp46 to aPSCs in fibrotic areas in DBTC rats was confirmed by fluorescence and radioactivity 24 h after the final injection. 10 systemic VA-lip-siRNAgp46 treatments resolved pancreatic fibrosis, and suppressed tissue hydroxyproline levels in DBTC- and cerulein-treated rats.. These data suggest the therapeutic potential of the present approach for reversing pancreatic fibrosis. Topics: Animals; Ceruletide; Collagen; Fibrosis; Gastrointestinal Agents; HSP47 Heat-Shock Proteins; Humans; Immunosuppressive Agents; Liposomes; Male; Models, Animal; Organotin Compounds; Pancreas; Pancreatitis, Chronic; Rats; Rats, Inbred Lew; Rats, Wistar; RNA, Small Interfering; Treatment Outcome; Vitamin A; Vitamins | 2013 |
Cerulein-induced chronic pancreatitis does not require intra-acinar activation of trypsinogen in mice.
Premature activation of trypsinogen activation can cause pancreatic injury and has been associated with chronic pancreatitis (CP). Mice that lack intra-acinar activation of trypsinogen, such as trypsinogen-7-null (T(-/-)) and cathepsin B-null (CB(-/-)) mice, have been used to study trypsin-independent processes of CP development. We compared histologic features and inflammatory responses of pancreatic tissues from these mice with those from wild-type mice after the development of CP.. CP was induced in wild-type, T(-/-), and CB(-/-) mice by twice-weekly induction of acute pancreatitis for 10 weeks; acute pancreatitis was induced by hourly intraperitoneal injections of cerulein (50 μg/kg × 6). Pancreatic samples were collected and evaluated by histologic and immunohistochemical analyses. Normal human pancreas samples, obtained from the islet transplant program at the University of Minnesota, were used as controls and CP samples were obtained from surgical resections.. Compared with pancreatic tissues from wild-type mice, those from T(-/-) and CB(-/-) mice had similar levels of atrophy, histomorphologic features of CP, and chronic inflammation. All samples had comparable intra-acinar activation of nuclear factor (NF)-κB, a transcription factor that regulates the inflammatory response, immediately after injection of cerulein. Pancreatic tissue samples from patients with CP had increased activation of NF-κB (based on nuclear translocation of p65 in acinar cells) compared with controls.. Induction of CP in mice by cerulein injection does not require intra-acinar activation of trypsinogen. Pancreatic acinar cells of patients with CP have increased levels of NF-κB activation compared with controls; regulation of the inflammatory response by this transcription factor might be involved in the pathogenesis of CP. Topics: Acinar Cells; Animals; Cells, Cultured; Ceruletide; Immunohistochemistry; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; Trypsinogen | 2013 |
Analysis of transplanted bone marrow-derived cells in chronic pancreatitis.
Pancreatic cancer is a uniformly lethal disease characterized by a strong stromal reaction called desmoplasia. Organ fibrosis is also a feature of chronic pancreatitis a known risk factor for pancreatic cancer. Here we describe a transplantation approach to investigate bone marrow-derived cells in murine models of chronic pancreatitis and pancreatic cancer. Topics: Animals; Bone Marrow Cells; Bone Marrow Transplantation; Cell Separation; Cell Tracking; Ceruletide; Disease Models, Animal; Humans; Mice; Pancreatic Neoplasms; Pancreatitis, Chronic; Whole-Body Irradiation | 2013 |
Recombinant human interleukin-1 receptor antagonist (rhIL-1Ra) attenuates caerulein-induced chronic pancreatitis in mice.
Chronic pancreatitis is a progressive inflammatory disease featuring irreversible irregular scarring of the exocrine parenchyma characterized by acinar destruction and fibrosis subsequent to inflammation in the pancreas. Despite decades of research, the knowledge is limited to the treatment of this disease. After finding a connection between interleukin-1β (IL-1β) and interleukin-1 receptor antagonist (IL-1Ra) in caerulein-induced chronic pancreatitis, we assumed that recombinant human IL-1Ra (rhIL-1Ra), the natural antagonist of IL-1β, might have a protective role in chronic pancreatitis in mice. Chronic pancreatitis was induced by repetitive intraperitoneal injections of caerulein in C57/BL mice followed by a consecutive administration of rhIL-1Ra (10mg/kg). Collagen content and histological changes in the pancreas as well as serum amylase and lipase were measured. We found that rhIL-1Ra significantly decreased the hydroxyproline and the fibrotic area in the pancreas after the caerulein challenge. Caerulein-induced serum amylase elevation and tissue damage were also attenuated in rhIL-1Ra treated mice. Our results reveal a potential role of rhIL-1Ra in protecting mice against caerulein-induced chronic pancreatitis and lead to a conclusion that this protein may be a potential candidate agent for the treatment of chronic pancreatitis in humans. Topics: Amylases; Animals; Ceruletide; Collagen; Disease Models, Animal; Fibrosis; Humans; Hydroxyproline; Injections, Intraperitoneal; Interleukin 1 Receptor Antagonist Protein; Interleukin-1beta; Lipase; Male; Mice; Mice, Inbred C57BL; Pancreatitis, Chronic | 2012 |
An NF-κB pathway-mediated positive feedback loop amplifies Ras activity to pathological levels in mice.
Genetic mutations that give rise to active mutant forms of Ras are oncogenic and found in several types of tumor. However, such mutations are not clear biomarkers for disease, since they are frequently detected in healthy individuals. Instead, it has become clear that elevated levels of Ras activity are critical for Ras-induced tumorigenesis. However, the mechanisms underlying the production of pathological levels of Ras activity are unclear. Here, we show that in the presence of oncogenic Ras, inflammatory stimuli initiate a positive feedback loop involving NF-κB that further amplifies Ras activity to pathological levels. Stimulation of Ras signaling by typical inflammatory stimuli was transient and had no long-term sequelae in wild-type mice. In contrast, these stimuli generated prolonged Ras signaling and led to chronic inflammation and precancerous pancreatic lesions (PanINs) in mice expressing physiological levels of oncogenic K-Ras. These effects of inflammatory stimuli were disrupted by deletion of inhibitor of NF-κB kinase 2 (IKK2) or inhibition of Cox-2. Likewise, expression of active IKK2 or Cox-2 or treatment with LPS generated chronic inflammation and PanINs only in mice expressing oncogenic K-Ras. The data support the hypothesis that in the presence of oncogenic Ras, inflammatory stimuli trigger an NF-κB-mediated positive feedback mechanism involving Cox-2 that amplifies Ras activity to pathological levels. Because a large proportion of the adult human population possesses Ras mutations in tissues including colon, pancreas, and lung, disruption of this positive feedback loop may be an important strategy for cancer prevention. Topics: Animals; Carcinoma, Pancreatic Ductal; Cell Transformation, Neoplastic; Ceruletide; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Enzyme Induction; Esters; Feedback, Physiological; Gabexate; Gene Expression Regulation, Neoplastic; Gene Knock-In Techniques; Genes, ras; Guanidines; Humans; I-kappa B Kinase; Inflammation; Inflammation Mediators; Lipopolysaccharides; Mice; Mice, Transgenic; Neoplasm Proteins; NF-kappa B; Pancreas; Pancreatic Neoplasms; Pancreatitis, Chronic; Precancerous Conditions; Proto-Oncogene Proteins p21(ras); Sincalide | 2012 |
The effect of sulindac, a non-steroidal anti-inflammatory drug, attenuates inflammation and fibrosis in a mouse model of chronic pancreatitis.
Chronic pancreatitis is characterized by progressive fibrosis, pain and loss of exocrine and endocrine functions. The long-standing chronic pancreatitis and its associated pancreatic fibrosis are the most common pathogenic events involved in human pancreatic carcinogenesis, but the therapeutic strategies to chronic pancreatitis and the chemoprevention of pancreatic carcinogenesis are very limited.. We investigated the effect of sulindac, a non-steroidal anti-inflammatory drug (NSAID), on inhibition of chronic pancreatitis in a caerulein induced chronic pancreatitis mouse model.. Sulindac significantly reduced the severity of chronic pancreatitis including the extent of acini loss, inflammatory cell infiltration and stromal fibrosis. The protein expression of phosphorylation of MEK/ERK was inhibited in the chronic pancreatic tissues by sulindac treatment as measured by Western blot assay. The levels of inflammatory cytokines including TNF-α and MCP-1 were also significantly decreased with sulindac treatment, as well as the expression of TGF-β, PDGF-β, SHH and Gli in the chronic pancreatic tissue detected by qPCR assay and confirmed by western blot assay. The activation of pancreatic satellet cells was also inhibited by sulindac as measured by the activity of α-smooth muscle actin (α-SMA) in the pancreatic tissue of chronic pancreatitis.. Sulindac is a promising reagent for the treatment of chronic pancreatitis via inhibition of inflammatory cell infiltration and stromal fibrosis, the inhibitory effect of sulindac on chronic pancreatitis may through targeting the activation ERK/MAPK signaling pathway. Topics: Acinar Cells; Actins; Animals; Anti-Inflammatory Agents, Non-Steroidal; Ceruletide; Cytokines; Disease Models, Animal; Female; Fibrosis; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; Phosphorylation; Severity of Illness Index; Sulindac; Treatment Outcome | 2012 |
Adult pancreatic acinar cells dedifferentiate to an embryonic progenitor phenotype with concomitant activation of a senescence programme that is present in chronic pancreatitis.
Acinar cells display plasticity in vitro and in vivo and can activate a variety of differentiation programmes that may contribute to pancreatic diseases. The aims were to determine: (1) the differentiation potential of acinar cells under conditions which favour stem cell survival, and (2) its relationship to the phenotypes acquired by pancreatic epithelial cells in chronic pancreatitis.. Murine acinar cells were cultured in suspension and their molecular phenotype was characterised by qRT-PCR, chromatin immunoprecipitation, immunocytochemistry and global transcriptome analysis. These findings were compared to the changes occurring in experimental chronic pancreatitis induced by pancreatic duct ligation and chronic caerulein administration.. Acinar cells in suspension culture acquired a dedifferentiated phenotype characteristic of pancreatic embryonic progenitors, consisting of the co-expression of Ptf1a and Pdx1, presence of an embryonic-type PTF1 transcriptional complex, activation of the Notch pathway, and expression of additional pancreatic progenitor cell markers such as CpA1, Sox9 and Hnf1b. A senescence programme, associated with activation of Ras and ERK signalling, limited the proliferative capacity of the cells. A similar progenitor-like phenotype with activation of a senescence programme was observed in experimental chronic pancreatitis induced by pancreatic duct ligation or repeated caerulein administration, with the concomitant and differential activation of proliferation and senescence in distinct cell populations.. Acinar cells dedifferentiate into an embryonic progenitor-like phenotype upon suspension culture. This is associated with the activation of a senescence programme. Both processes take place in experimental chronic pancreatitis where senescence may contribute to limit tumour progression. Topics: Animals; Cell Dedifferentiation; Cells, Cultured; Cellular Senescence; Ceruletide; Disease Models, Animal; Embryonic Stem Cells; Gene Expression Profiling; Mice; Mice, Inbred C57BL; Pancreas, Exocrine; Pancreatitis, Chronic; Phenotype; Reverse Transcriptase Polymerase Chain Reaction; Up-Regulation | 2011 |
COX-2 is not required for the development of murine chronic pancreatitis.
Chronic pancreatitis is a severe inflammation of the pancreas associated with destruction of the parenchyma, fibrosis, and persistent abdominal pain. Cyclooxygenase-2 (COX-2) and COX-2-derived prostaglandins, key mediators of the inflammatory response, are elevated in patients with chronic pancreatitis. Previous studies investigated COX-2 as a therapeutic target. These reports showed a reduced pathology in COX-2-deficient mice with a better outcome. Here we compared the role of COX-2 in acute and chronic pancreatic inflammation using the same COX-2(-/-) mouse model of cerulein-induced pancreatitis. In a setting of acute pancreatitis, juvenile COX-2(-/-) mice exhibited a reduced histopathological score compared with wild-type littermates; on the contrary, adult mice did not show any difference in the development of the disease. Similarly, in a setting of chronic pancreatitis induced over a period of 4 wk, adult mice of the two strains showed comparable histological score and collagen deposition. However, the abundance of mRNAs coding for profibrotic genes, such as collagen, α-smooth muscle actin, and transforming growth factor-β was consistently lower in COX-2(-/-) mice. In addition, comparable histological scores and collagen deposition were observed in wild-type mice treated with a COX-2 inhibitor. We conclude that, in contrast to what was observed in the rat pancreatitis models, COX-2 has a limited and age-dependent effect on inflammatory processes in the mouse pancreas. These results suggest that COX-2 modulates the inflammatory process during the development of pancreatitis in a species-specific manner. Thus the pathophysiological roles of COX-2 and its therapeutic implications in patients with pancreatitis should be reexamined. Topics: Actins; Age Factors; Animals; Ceruletide; Collagen; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Disease Models, Animal; Gene Expression Regulation; Lactones; Mice; Mice, Knockout; Pancreas; Pancreatitis, Chronic; Species Specificity; Sulfones; Time Factors; Transforming Growth Factor beta | 2011 |
Myeloid, but not pancreatic, RelA/p65 is required for fibrosis in a mouse model of chronic pancreatitis.
Little is known about how transcription factors might regulate pathogenesis of chronic pancreatitis (CP). We analyzed the in vivo role of RelA/p65, a component of the transcription factor nuclear factor (NF)-κB, in different cell types during development of CP in mice.. RelA/p65 was functionally inactivated in the pancreas (relaΔpanc), in myeloid cells (relaΔmye), or both (relaΔpanc,Δmye) compartments using the Cre-loxP strategy. Experimental CP was induced with repetitive injections of cerulein over 6 weeks. Pancreata were investigated histologically and biochemically. We created an in vitro coculture assay of pancreatic stellate cells (PSC) and macrophages and performed gene arrays from pancreata and macrophages with functionally inactivated RelA/p65. Tissue samples from patients with CP were analyzed for matrix metalloproteinase (MMP) 10 expression.. In contrast to their relaF/F littermates, relaΔpanc displayed typical signs of CP after long-term stimulation with cerulein. Numerous macrophages and activated α-smooth muscle actin (SMA)-positive PSCs were detected. Additional inactivation of RelA/p65 in myeloid cells (relaΔpanc,Δmye) attenuated fibrosis. In vitro, RelA/p65-deficient, lipopolysaccharide (LPS)-stimulated macrophages degraded fibronectin in cocultured PSCs. Using gene expression analysis, MMP-10 was identified as a candidate for this process. Recombinant MMP-10 degraded fibronectin in LPS-stimulated PSCs. In tissue samples from patients with CP, MMP-10 was up-regulated in myeloid cells.. RelA/p65 functions in myeloid cells to promote pathogenesis of CP. In acinar cells, RelA/p65 protects against chronic inflammation, whereas myeloid RelA/p65 promotes fibrogenesis. In macrophage, MMP-10 functions as a RelA/p65-dependent, potentially antifibrogenic factor during progression of CP. Topics: Actins; Animals; Case-Control Studies; Cells, Cultured; Ceruletide; Coculture Techniques; Disease Models, Animal; Fibronectins; Fibrosis; Humans; Lipopolysaccharides; Macrophages; Matrix Metalloproteinase 10; Mice; Mice, Knockout; Myeloid Cells; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Time Factors; Transcription Factor RelA | 2011 |
Inhibition of chronic pancreatitis and pancreatic intraepithelial neoplasia (PanIN) by capsaicin in LSL-KrasG12D/Pdx1-Cre mice.
Capsaicin is a major biologically active ingredient of chili peppers. Extensive studies indicate that capsaicin is a cancer-suppressing agent via blocking the activities of several signal transduction pathways including nuclear factor-kappaB, activator protein-1 and signal transducer and activator of transcription 3. However, there is little study on the effect of capsaicin on pancreatic carcinogenesis. In the present study, the effect of capsaicin on pancreatitis and pancreatic intraepithelial neoplasia (PanIN) was determined in a mutant Kras-driven and caerulein-induced pancreatitis-associated carcinogenesis in LSL-Kras(G12D)/Pdx1-Cre mice. Forty-five LSL-Kras(G12D)/Pdx1-Cre mice and 10 wild-type mice were subjected to one dose of caerulein (250 μg/kg body wt, intraperitoneally) at age 4 weeks to induce and synchronize the development of chronic pancreatitis and PanIN lesions. One week after caerulein induction, animals were randomly distributed into three groups and fed with either AIN-76A diet, AIN-76A diet containing 10 p.p.m. capsaicin or 20 p.p.m. capsaicin for a total of 8 weeks. The results showed that capsaicin significantly reduced the severity of chronic pancreatitis, as determined by evaluating the loss of acini, inflammatory cell infiltration and stromal fibrosis. PanIN formation was frequently observed in the LSL-Kras(G12D)/Pdx1-Cre mice. The progression of PanIN-1 to high-grade PanIN-2 and -3 were significantly inhibited by capsaicin. Further immunochemical studies revealed that treatment with 10 and 20 p.p.m. capsaicin significantly reduced proliferating cell nuclear antigen-labeled cell proliferation and suppressed phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun as well blocked Hedgehog/GLI pathway activation. These results indicate that capsaicin could be a promising agent for the chemoprevention of pancreatic carcinogenesis, possibly via inhibiting pancreatitis and mutant Kras-led ERK activation. Topics: Animals; Blotting, Western; Capsaicin; Capsicum; Carcinoma in Situ; Cell Transformation, Neoplastic; Ceruletide; Extracellular Signal-Regulated MAP Kinases; Female; Homeodomain Proteins; Immunoenzyme Techniques; Integrases; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Pancreatic Neoplasms; Pancreatitis, Chronic; Proto-Oncogene Proteins p21(ras); Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sensory System Agents; Trans-Activators; Transcription Factor AP-1 | 2011 |
Overexpression of Smad6 exacerbates pancreatic fibrosis in murine caerulein-induced chronic pancreatic injuries.
We examined the effect of the overexpression of Smad6 on pancreatic fibrosis after chronic pancreatic injury.. Chronic pancreatic injury was induced in transgenic mice overexpressing Smad6 (Tg mice) in acini and wild-type (Wt) mice by 3 episodes of acute pancreatitis per week for 1 to 4 consecutive weeks. Acute pancreatitis was elicited by 6 intraperitoneal injections of caerulein (Cn) at 50 microg/kg of body weight at hourly intervals. Pancreatic fibrosis was evaluated by histological examination and hydroxyproline content before and 1, 2, 3, and 4 weeks of repetitive episodes of Cn-induced acute pancreatitis. We further determined transforming growth factor beta1 (TGF-beta1) messenger RNA expression and trypsin activity in the pancreas.. After repetitive episodes of acute pancreatitis, pancreatic fibrosis in Tg mice was significantly severer than that in Wt mice at all time points (weeks 1-4). The expression of TGF-beta1 messenger RNA and the activity of trypsin in the pancreas in the Tg mice were significantly high compared with those in the Wt mice at all corresponding time points after repetitive episodes of acute pancreatitis.. These results demonstrated that overexpression of Smad6 in acini enhanced the development of pancreatic fibrosis after chronic pancreatic injury. Topics: Animals; Ceruletide; Disease Progression; Fibrosis; Male; Mice; Mice, Transgenic; Pancreatitis, Chronic; Smad6 Protein; Transforming Growth Factor beta; Trypsin | 2010 |
Protection against chronic pancreatitis and pancreatic fibrosis in mice overexpressing pancreatic secretory trypsin inhibitor.
Mutations in the gene encoding for pancreatic secretory trypsin inhibitor (PSTI) can contribute to chronic pancreatitis. In the current study, we tested whether overexpression of PSTI-I in mice protects against chronic pancreatitis and pancreatic fibrosis.. Rat PSTI-I expression was targeted to pancreatic acinar cells in transgenic mice. Chronic pancreatitis was achieved by intraperitoneal injection of cerulein for 10 weeks. Pancreatitis severity was assessed by histological grading of inflammatory infiltrate, atrophy, and fibrosis; quantitation of myeloperoxidase (MPO) activity; quantitative morphometric analysis of collagen content; and measurements of type I collagen, fibronectin, and transforming growth factor beta mRNA expression.. Cerulein administration to nontransgenic mice produced histological evidence of inflammatory infiltrate, glandular atrophy, and parenchymal fibrosis and increased collagen production, MPO activity, and collagen I and fibronectin mRNA levels. In cerulein-treated PSTI transgenic mice, there were significant reductions in inflammatory infiltrate, MPO activity, fibrosis, and collagen I and fibronectin mRNA levels. Transgenic mice treated with cerulein had significantly less collagen than nontransgenic mice.. The severity of chronic pancreatitis and pancreatic fibrosis is significantly reduced in mice expressing rat PSTI-I. We propose that pancreatic trypsin inhibitors play a protective role in the pancreatic response to repeated injurious events. Topics: Animals; Ceruletide; Collagen; Collagen Type I; Fibronectins; Fibrosis; Gene Expression Profiling; Intercellular Signaling Peptides and Proteins; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Pancreas; Pancreatitis, Chronic; Peroxidase; Rats; Severity of Illness Index; Transforming Growth Factor beta; Trypsin Inhibitor, Kazal Pancreatic | 2010 |
Pancreatic duct glands are distinct ductal compartments that react to chronic injury and mediate Shh-induced metaplasia.
Pancreatic intraepithelial neoplasia (PanIN) are pancreatic cancer precursor lesions of unclear origin and significance. PanIN aberrantly express sonic hedgehog (Shh), an initiator of pancreatic cancer, and gastrointestinal mucins. A majority of PanIN are thought to arise from ducts. We identified a novel ductal compartment that is gathered in gland-like outpouches (pancreatic duct glands [PDG]) of major ducts and characterized its role in injury and metaplasia.. The ductal system was analyzed in normal pancreata and chronic pancreatitis in humans and mice. Anatomy was assessed by serial hematoxylin and eosin sections and scanning electron microscopy of corrosion casts. Expression of mucins and developmental genes and proliferation were assessed by immunohistochemistry or real-time quantitative polymerase chain reaction. Effects of Shh on ductal cells were investigated by exposure to Shh in vitro and transgenic misexpression in vivo.. Three-dimensional analysis revealed blind-ending outpouches of ducts in murine and human pancreata. These PDG are morphologically and molecularly distinct from normal ducts; even in normal pancreata they display PanIN and metaplastic features, such as expression of Shh and gastric mucins. They express other developmental genes, such as Pdx-1 and Hes-1. In injury, Shh is up-regulated along with gastric mucins. Expansion of the PDG compartment results in a mucinous metaplasia. Shh promotes this transformation in vitro and in vivo.. PDG are distinct gland-like mucinous compartments with a distinct molecular signature. In response to injury, PDG undergo an Shh-mediated mucinous gastrointestinal metaplasia with PanIN-like features. PDG may provide a link between Shh, mucinous metaplasia, and neoplasia. Topics: Animals; Carcinoma in Situ; Cells, Cultured; Ceruletide; Corrosion Casting; Disease Models, Animal; Epithelial Cells; Gastric Mucins; Gene Expression Regulation, Developmental; Hedgehog Proteins; Humans; Immunohistochemistry; Metaplasia; Mice; Mice, Transgenic; Pancreatic Ducts; Pancreatic Neoplasms; Pancreatitis, Chronic; Precancerous Conditions; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Time Factors | 2010 |
Adiponectin deficiency enhanced the severity of cerulein-induced chronic pancreatitis in mice.
Adiponectin is recognized as an antiinflammatory and antifibrotic protein derived from adipocytes, and low serum adiponectin levels are present in obesity. Recent studies have highlighted the relationship between obesity and pancreatic diseases. However, the role of adiponectin in chronic pancreatitis remains uncertain. The aim of this study was to determine the effects of adiponectin in chronic pancreatitis.. We investigated the effects of adiponectin in experimental chronic pancreatitis by using adiponectin-knockout (APN-KO) mice. Chronic pancreatitis was induced by repeated hourly (6 times) intraperitoneal injections of 50 microg/kg cerulein three times per week for 4 weeks in wild-type (WT) and APN-KO mice. We evaluated the severity of chronic pancreatitis biochemically and morphologically.. In cerulein-treated mice, macroscopically and histologically, severe pancreatic damage was observed in APN-KO mice compared with findings in WT mice. The histological scores for chronic pancreatitis, including glandular atrophy, pseudotubular complex, fibrosis, and total scores, were significantly higher in APN-KO mice than in WT mice. Activated pancreatic stellate cells and F4/80-positive pancreatic macrophages accumulated in the pancreas of APN-KO mice but not in WT mice. Overexpression of the mRNAs of transforming growth factor-beta1, CD68, and monocyte chemoattractant protein-1 was noted in APN-KO mice but not in WT mice. The gene expression level of collagen1 (alpha1) tended to be higher in APN-KO mice than in WT mice, albeit insignificantly.. Adiponectin deficiency enhanced the severity of cerulein-induced chronic pancreatitis in mice. Hypoadiponectinemia could enhance the severity of chronic pancreatitis. Topics: Adiponectin; Animals; Ceruletide; Disease Models, Animal; Gene Expression Regulation; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Pancreas; Pancreatitis, Chronic; Severity of Illness Index | 2010 |
Connective tissue growth factor production by activated pancreatic stellate cells in mouse alcoholic chronic pancreatitis.
Alcoholic chronic pancreatitis (ACP) is characterized by pancreatic necrosis, inflammation, and scarring, the latter of which is due to excessive collagen deposition by activated pancreatic stellate cells (PSC). The aim of this study was to establish a model of ACP in mice, a species that is usually resistant to the toxic effects of alcohol, and to identify the cell type(s) responsible for production of connective tissue growth factor (CTGF), a pro-fibrotic molecule. C57Bl/6 male mice received intraperitoneal ethanol injections for 3 weeks against a background of cerulein-induced acute pancreatitis. Peak blood alcohol levels remained consistently high in ethanol-treated mice as compared with control mice. In mice receiving ethanol plus cerulein, there was increased collagen deposition as compared with other treatment groups as well as increased frequency of alpha-smooth muscle actin and desmin-positive PSC, which also showed significantly enhanced CTGF protein production. Expression of mRNA for collagen alpha1(I), alpha-smooth muscle actin or CTGF were all increased and co-localized exclusively to activated PSC in ACP. Pancreatic expression of mRNA for key profibrotic markers were all increased in ACP. In conclusion, a mouse model of ACP has been developed that mimics key pathophysiological features of the disease in humans and which shows that activated PSC are the principal producers of collagen and CTGF. PSC-derived CTGF is thus a candidate therapeutic target in anti-fibrotic strategies for ACP. Topics: Alcoholics; Alcoholism; Animals; Ceruletide; Collagen; Connective Tissue Growth Factor; Ethanol; Extracellular Matrix; Fibrosis; Male; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis; Pancreatitis, Alcoholic; Pancreatitis, Chronic; RNA, Messenger | 2010 |
Angiotensin II signaling through the AT1a and AT1b receptors does not have a role in the development of cerulein-induced chronic pancreatitis in the mouse.
The intraorgan renin-angiotensin system (RAS) plays an important role in the pathophysiology of a variety of diseases and has been implicated in fibrogenesis. The role of RAS in the development of chronic pancreatitis is not well established. The blockade of RAS in rat models with angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor 1 (AT1) blockers (ARBs) mostly have reduced pancreatic inflammation and fibrosis with a few exceptions. At the same time, the use of ACEi and ARBs in humans is associated with a modest risk of acute pancreatitis. The aim of this study was to elucidate the effect of the AT1 signaling pathway in the development of pancreatitis using AT1a- and AT1b-deficient mice as well as the ARB losartan. Chronic pancreatitis was induced by repetitive cerulein administration in C57BL/6J wild-type (WT) and AT1a- and AT1b-deficient mice (AT1a-/- and AT1b-/-), and pancreatic injury was assessed at day 10. Pancreatic weight of cerulein treated groups was significantly reduced. There was severe parenchymal atrophy and fibrosis assessed by histological examination. Fibrosis was accompanied by activation of pancreatic stellate cells (PSC) evaluated by Western blot analysis for alpha-smooth muscle actin. No differences were seen between cerulein-treated WT, AT1a-/- , AT1b-/- mice, or losartan treated-WT mice with regards to morphological or molecular alterations induced by cerulein. Our results demonstrate that AT1a and AT1b receptor pathways do not seem to be essential for the development of pancreatitis in the mouse model of pancreatitis induced by repetitive cerulein injury. Topics: Actins; Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Animals; Atrophy; Ceruletide; Collagen; Disease Models, Animal; Fibrosis; Losartan; Mice; Mice, Inbred C57BL; Mice, Knockout; Pancreas; Pancreatitis, Chronic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; RNA, Messenger; Severity of Illness Index; Signal Transduction | 2010 |
Protection of cerulein-induced pancreatic fibrosis by pancreas-specific expression of Smad7.
Pancreatic fibrosis is the hallmark of chronic pancreatitis, currently an incurable disease. Pancreatitis fibrosis is caused by deposition of extracellular matrix (ECM) and the underlying pathological mechanism remains unclear. In addition to its broad biological activities, TGF-beta is a potent pro-fibrotic factor and many in vitro studies using cell systems have implicated a functional role of TGF-beta in the pathogenesis of pancreatic fibrosis. We analyzed the in vivo role of TGF-beta pathway in pancreatic fibrosis in this study. Smad7, an intracellular inhibitory protein that antagonizes TGF-beta signaling, was specifically expressed in the pancreas using a transgenic mouse model. Chronic pancreatitis was induced in the mouse with repeated administration of cerulein. Smad7 expression in the pancreas was able to significantly inhibit cerulein-induced pancreatic fibrosis. Consistently, the protein levels of collagen I and fibronectin were decreased in the Smad7 transgenic mice. In addition, alpha-smooth muscle actin, a marker of activated pancreas stellate cells, was reduced in the transgenic mice. Taken together, these data indicate that inhibition of TGF-beta signaling by Smad7 is able to protect cerulein-induced pancreatic fibrosis in vivo. Topics: Actins; Animals; Base Sequence; Ceruletide; Collagen Type I; DNA Primers; Female; Fibronectins; Fibrosis; Gene Expression; Male; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Organ Specificity; Pancreas; Pancreatitis, Chronic; Recombinant Proteins; Signal Transduction; Smad7 Protein; Transforming Growth Factor beta | 2009 |
Bone marrow contributes to the population of pancreatic stellate cells in mice.
Activated pancreatic stellate cells (PSCs) play a pivotal role in the development of pancreatic fibrosis. The origin of activated PSCs has been thought to be transformation of quiescent PSCs residing locally in the pancreas. Recent studies have suggested that bone marrow (BM)-derived cells participate in regeneration processes in various organs. This study aimed to clarify the contribution of BM-derived cells to the population of PSCs in mice. We transplanted BM cells from male enhanced green fluorescent protein transgenic mice into female C57BL/6 mice after lethal irradiation. Eight weeks after BM transplantation, chronic pancreatitis was induced by administration of six intra-abdominal injections of cerulein (50 microg/kg body wt) at 1-h intervals, 3 days per week, for the total of 6 wk. BM-derived cells were tracked by green fluorescent protein expression and in situ hybridization for the Y-chromosome. Eight weeks after BM transplantation, BM-derived cells accounted for 8.7% of the desmin (a marker of PSCs)-positive cells in the pancreas. We could isolate BM-derived cells, which contained lipid droplets and expressed desmin. They could be transformed to myofibroblast-like cells by culture in vitro, further supporting that BM contributed to the population of quiescent PSCs. After induction of pancreatic fibrosis, BM-derived cells accounted for 20.2% of alpha-smooth muscle actin-positive activated PSCs. The contribution of BM-derived cells to pancreatic ductal cells (positive for cytokeratin-19) was rare and less than 1%. In conclusion, our results suggested that BM-derived cells contributed to the population of PSCs in mice. Topics: Actins; Animals; Bone Marrow Cells; Bone Marrow Transplantation; Cell Differentiation; Cell Movement; Ceruletide; Desmin; Disease Models, Animal; Female; Fibrosis; Green Fluorescent Proteins; Lipid Metabolism; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Pancreas; Pancreatic Ducts; Pancreatitis, Chronic; Time Factors; Y Chromosome | 2009 |
Role of bone marrow-derived cells in experimental chronic pancreatitis.
Chronic pancreatitis is a known risk factor for pancreatic adenocarcinoma. Recent work has pointed to a role for bone marrow-derived progenitor cells (BMDCs) in chronic inflammation-based carcinogenesis. Consequently, the role of BMDCs in chronic pancreatitis was investigated.. The fate of BMDCs was followed using green fluorescent protein and the Y chromosome as bone marrow markers in gender-mismatched transplanted mice treated with repeated injections of cerulein for up to 45 weeks. The phenotype of engrafted BMDCs was assessed based on the co-expression of bone marrow and pancreatic markers.. After 45 weeks of cerulein treatment, mice developed severe chronic pancreatitis but no preneoplastic lesions. BMDCs did engraft in the pancreas. Most of the BMDCs were desmin positive and contributed to 5.12% (1.12%) (mean (SEM)) of the pancreatic stellate cell population. Pancreatic stellate cells derived from the bone marrow could be activated, as demonstrated by alpha-smooth muscle actin expression, suggesting a role in tissue repair. BMDCs could also be found in pancreatic ducts, based on dolichos biflorus agglutinin and cytokeratin 19 stainings, but at a much lower frequency (0.62% (0.11%)).. BMDCs contribute to the pancreatic stellate cell population, suggesting a role in pancreatic tissue repair. In the absence of preneoplastic lesions, BMDCs contribute at a very low level to the ductal epithelium of the chronically inflamed pancreas. The role of BMDCs in pancreatic carcinogenesis remains to be defined. Topics: Animals; Bone Marrow Cells; Bone Marrow Transplantation; Ceruletide; Disease Models, Animal; Green Fluorescent Proteins; Immunoenzyme Techniques; In Situ Hybridization; Male; Mice; Mice, Inbred C57BL; Microscopy, Confocal; Pancreatitis, Chronic; Stem Cells; Y Chromosome | 2008 |
A case of mistaken identity? Nonductal origins of pancreatic "ductal" cancers.
In this issue of Cancer Cell, Guerra and colleagues provide important new insights regarding the ability of specific pancreatic cell types to generate invasive pancreatic cancer. First, they demonstrate that classical pancreatic "ductal" neoplasia can be induced by activation of oncogenic Kras in nonductal exocrine cells. Second, they show that, while Kras activation in immature acinar and centroacinar cells is readily able to induce ductal neoplasia, Kras-mediated tumorigenesis in mature exocrine pancreas requires the induction of chronic epithelial injury. The results shed new light on the "cell of origin" of pancreatic ductal cancer and demonstrate that chronic pancreatitis provides a permissive environment for Kras-induced pancreatic neoplasia. Topics: Animals; Carcinoma in Situ; Carcinoma, Pancreatic Ductal; Cell Lineage; Cell Transformation, Neoplastic; Ceruletide; Genes, ras; Humans; Mice; Mutation; Neoplasm Invasiveness; Pancreatic Neoplasms; Pancreatitis, Chronic | 2007 |
Chronic pancreatitis is essential for induction of pancreatic ductal adenocarcinoma by K-Ras oncogenes in adult mice.
Pancreatic ductal adenocarcinoma (PDA), one of the deadliest human cancers, often involves somatic activation of K-Ras oncogenes. We report that selective expression of an endogenous K-Ras(G12V) oncogene in embryonic cells of acinar/centroacinar lineage results in pancreatic intraepithelial neoplasias (PanINs) and invasive PDA, suggesting that PDA originates by differentiation of acinar/centroacinar cells or their precursors into ductal-like cells. Surprisingly, adult mice become refractory to K-Ras(G12V)-induced PanINs and PDA. However, if these mice are challenged with a mild form of chronic pancreatitis, they develop the full spectrum of PanINs and invasive PDA. These observations suggest that, during adulthood, PDA stems from a combination of genetic (e.g., somatic K-Ras mutations) and nongenetic (e.g., tissue damage) events. Topics: Animals; Carcinoma in Situ; Carcinoma, Pancreatic Ductal; Cell Lineage; Cell Transformation, Neoplastic; Ceruletide; Doxycycline; Genes, ras; Liver Neoplasms; Lung Neoplasms; Mice; Mice, Mutant Strains; Mutation; Neoplasm Invasiveness; Pancreas; Pancreatic Neoplasms; Pancreatitis, Chronic; Signal Transduction | 2007 |
Induced thrombospondin expression in the mouse pancreas during pancreatic injury.
Chronic pancreatitis is a disease characterized by pancreatic fibrogenesis in response to sustained or repetitive injury. Pancreatic stellate cells (PSC) are interstitial cells that produce excessive extracellular matrix components during the process of fibrogenesis and therefore play a central role in the pathogenesis of chronic pancreatitis. Because the matricellular proteins thrombospondin-1 (TSP-1) and TSP-2 have a role in regulating fibrogenesis in other tissues, the expression of these major TSP isoforms in the whole pancreas was measured in a mouse model of repetitive pancreatic injury. Specifically, mice were treated with cerulein, 50 microg/kg/h x 6h with treatments repeated once or twice every 48 h. Expression was also evaluated in cultured PSC. PSC were isolated by outgrowth from normal mouse pancreas and expression of TSP-1 and TSP-2 was evaluated after serum-activation. The mRNA transcripts for TSP-1 and TSP-2 were increased, 16-fold and 87-fold respectively, in the pancreas in response to repetitive injury. In cultured PSC, these transcripts were also increased in response to serum and increases in mRNA were reflected by the secretion of TSP-1 and TSP-2 proteins by PSC into culture media. In summary, PSC may be an important source of both TSP-1 and TSP-2 in the pancreas in response to injury. These modulators of fibrogenesis could play a role in the development of pancreatic fibrosis that characterizes chronic pancreatitis. Topics: Animals; Cells, Cultured; Ceruletide; Female; Fibrosis; Gene Expression Regulation; Mice; Pancreas; Pancreatitis, Chronic; Thrombospondin 1; Thrombospondins | 2006 |
Establishment of animal models for three types of pancreatitis and analyses of regeneration mechanisms.
To investigate the mechanisms underlying the onset and progress of pancreatitis, 3 animal models (chronic, acute, and severe pancreatitis) were established by double ligature of the pancreatic duct, injection with cerulein, or injection with cerulein + double ligature of the pancreatic duct.. We prepared a control and 3 experimental groups: group 1 (untreated control), group 2 (a chronic pancreatitis model; the pancreatic tail was exposed through a midline incision, and the pancreatic duct from this part was double-ligated), group 3 (an acute pancreatitis model; cerulein was intraperitoneally injected 7 times on day 0), and group 4 (a severe pancreatitis model; the double ligature of the pancreatic duct plus injection of cerulein).. Kinetic observations of survival rate, relative pancreatic weight, and the macroscopical and microscopical diagnoses and observations of the changes in endocrine function clearly show that these 3 murine models of pancreatitis can serve as human models for chronic, acute, and severe pancreatitis. Furthermore, pancreas duodenum homeobox 1, cytokeratin 19, and Ki67 are expressed at the site of injury in the pancreas, resulting from the injection with cerulein and/or double ligature of the pancreatic ducts and indicating that there remains a tissue-regenerative capacity.. These 3 mouse models could serve as human models for chronic, acute, and severe pancreatitis. Furthermore, cells of the epithelial lineage might participate in tissue regeneration in chronic, acute, and severe pancreatitis. Topics: Amylases; Animals; Apoptosis; Biomarkers; Blood Glucose; Cell Proliferation; Ceruletide; Disease Models, Animal; Female; Fibrosis; Homeodomain Proteins; Insulin; Keratin-19; Ligation; Mice; Mice, Inbred C57BL; Organ Size; Pancreas; Pancreatic Ducts; Pancreatitis, Acute Necrotizing; Pancreatitis, Chronic; Regeneration; Severity of Illness Index; Time Factors; Trans-Activators | 2006 |
A mouse model of hereditary pancreatitis generated by transgenic expression of R122H trypsinogen.
Missense mutations in human cationic trypsinogen PRSS1 are frequently detected in patients with hereditary pancreatitis, a rare genetic disease of the pancreas characterized by autodigestive necrosis, chronic inflammation, and fibrosis. To examine the link between PRSS1 mutations and the initiation and progression of hereditary pancreatitis, we have sought to generate a transgenic mouse that carries a missense mutation in the PRSS1 that is most frequently observed in patients.. A transgenic mouse was generated in which the expression of the mouse PRSS1 mutant R122H (R122H_mPRSS1) is targeted to pancreatic acinar cells by fusion to the elastase promoter. The expression of the mutant trypsinogen was assessed by immunohistochemical staining and real-time reverse transcription polymerase chain reaction analysis. The relationship between transgene expression and inflammation was analyzed by morphologic assessment of H&E-stained tissue sections, responsiveness to cerulein-induced pancreatitis, and immunohistochemical identification of cellular and biochemical components of the inflammatory response.. Pancreata from transgenic mice display early-onset acinar cell injury and inflammatory cell infiltration. With progressing age, the transgenic mice develop pancreatic fibrosis and display acinar cell dedifferentiation. Moreover, the expression of R122H_mPRSS1 transgene is associated with enhanced response to cerulein-induced pancreatitis. Finally, cell-specific activation of the inflammation-associated signaling pathways, c-jun-N-terminal kinase and extracellular signal-regulated kinase, was observed in response to expression of R122H_mPRSS1.. These results underscore the importance of PRSS1 mutations as pathogenic mediators of hereditary pancreatitis and indicate that persistent pancreatic injury might be causally linked to chronic pancreatitis. Topics: Animals; Ceruletide; Disease Models, Animal; Disease Progression; DNA; Gene Expression Regulation; Inflammation; Mice; Mice, Inbred C57BL; Mice, Transgenic; Mutation, Missense; Pancreas; Pancreatitis, Chronic; Phenotype; Trypsinogen | 2006 |
Amelioration of pancreatic fibrosis in mice with defective TGF-beta signaling.
Pancreatic fibrosis is a characteristic feature of chronic pancreatic injury, which is a result of the imbalance between synthesis and degradation of extracellular matrix (ECM) proteins. Transforming growth factor-beta (TGF-beta) plays a central role in biosynthesis and turnover of the ECM. In this study, we evaluated the role of TGF-beta signaling in pancreatic fibrosis induced by repetitive acute pancreatic injuries with mice of dominant-negative mutant of TGF-beta receptor II selectively in pancreas.. TGF-beta signaling was inactivated by overexpressing a dominant-negative mutant form of TGF-beta type II receptor (pS2-dnR II) only in the pancreas under control of pS2/TFF1 promoter. Pancreatic fibrosis was induced by repeated intraperitoneal injections of 40 microg/kg cerulein for 5 or 10 weeks.. Repeated administration of cerulein induced significant pancreatic fibrosis, but of which fibrosis was remarkably attenuated in pS2-dnR II mice compared with wild-type littermates (P < 0.01). The ameliorated fibrosis was due to the reduction of synthesis of ECM proteins such as collagen type I, fibronectin, and ICAM-1. DNA binding activity of transcriptional factors including nuclear factor (NF)-kappaB and AP-1, responsible for the induction of immediate early genes of inflammatory responses, were significantly decreased in pS2-dnR II mice. While TGF-beta1 treatment in isolated pancreatic stellate cells (PSCs) stimulated the expression of alpha-SMA and fibronectin, PSCs transfected with TGF-beta dnRII showed attenuation of the ECM components.. Conditional loss of TGF-beta signaling selectively in the pancreas led to a failure in fibrogenic responses of repeated injections of cerulein, signifying that the modulation of TGF-beta signaling could be the therapeutic target for the prevention of chronic fibrosing pancreatitis. Topics: Animals; Cells, Cultured; Ceruletide; Extracellular Matrix Proteins; Fibrosis; Male; Mice; Mice, Inbred Strains; Mice, Transgenic; NF-kappa B; Pancreas; Pancreatitis, Chronic; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Signal Transduction; Transcription Factor AP-1; Transcription, Genetic; Transfection; Transforming Growth Factor beta; Transforming Growth Factor beta1 | 2005 |