Cathepsin B inhibition prevents trypsinogen activation and reduces pancreatitis severity

2002 ◽  
Vol 283 (3) ◽  
pp. G794-G800 ◽  
Author(s):  
Gijs J. D. van Acker ◽  
Ashok K. Saluja ◽  
Lakshmi Bhagat ◽  
Vijay P. Singh ◽  
Albert M. Song ◽  
...  
Keyword(s):  
Acute Pancreatitis ◽  
Acinar Cell ◽  
Cathepsin B ◽  
Cell Activation ◽  
Cell Injury ◽  
Critical Role ◽  
Trypsinogen Activation ◽  
Soluble Cell

Intrapancreatic activation of trypsinogen is believed to play a critical role in the initiation of acute pancreatitis, but mechanisms responsible for intrapancreatic trypsinogen activation during pancreatitis have not been clearly defined. In previous in vitro studies, we have shown that intra-acinar cell activation of trypsinogen and acinar cell injury in response to supramaximal secretagogue stimulation could be prevented by the cell permeant cathepsin B inhibitor E64d (Saluja A, Donovan EA, Yamanaka K, Yamaguchi Y, Hofbauer B, and Steer ML. Gastroenterology 113: 304–310, 1997). The present studies evaluated the role of intrapancreatic trypsinogen activation, this time under in vivo conditions, in two models of pancreatitis by using another highly soluble cell permeant cathepsin B inhibitor,l-3-trans-(propylcarbamoyl)oxirane-2-carbonyl-l-isoleucyl-l-proline methyl ester (CA-074me). Intravenous administration of CA-074me (10 mg/kg) before induction of either secretagogue-elicited pancreatitis in mice or duct infusion-elicited pancreatitis in rats markedly reduced the extent of intrapancreatic trypsinogen activation and substantially reduced the severity of both pancreatitis models. These observations support the hypothesis that, during the early stages of pancreatitis, trypsinogen activation in the pancreas is mediated by the lysosomal enzyme cathepsin B. Our findings also suggest that pharmacological interventions that inhibit cathepsin B may prove useful in preventing acute pancreatitis or reducing its severity.

Secretagogue-induced digestive enzyme activation and cell injury in rat pancreatic acini

1999 ◽  
Vol 276 (4) ◽  
pp. G835-G842 ◽  
Author(s):  
A. K. Saluja ◽  
L. Bhagat ◽  
H. S. Lee ◽  
M. Bhatia ◽  
J. L. Frossard ◽  
...  
Keyword(s):  
Acinar Cell ◽  
Cell Activation ◽  
Cell Injury ◽  
Digestive Enzyme ◽  
Enzyme Activation ◽  
Critical Event ◽  
Pancreatic Acini ◽  
Trypsinogen Activation ◽  
Intracellular Ca

The mechanisms responsible for intrapancreatic digestive enzyme activation as well as the relationship between that activation and cell injury during pancreatitis are not understood. We have employed an in vitro system in which freshly prepared pancreatic acini are exposed to a supramaximally stimulating concentration of the CCK analog caerulein to explore these issues. We find that in vitro trypsinogen activation depends on the continued presence of Ca2+in the suspending medium and that it is half-maximal in the presence of 0.3 mM Ca2+. Caerulein-induced trypsinogen activation can be halted by removal of Ca2+from the suspending medium or by chelation of intracellular Ca2+. Increasing intracellular Ca2+with either ionomycin or thapsigargin does not induce trypsinogen activation. We have monitored cell injury by measuring the leakage of lactate dehydrogenase (LDH) from acini and by quantitating intercalation of propidium iodide (PI) into DNA. Leakage of LDH and intercalation of PI in response to supramaximal stimulation with caerulein can be detected only after caerulein-induced trypsinogen activation has already occurred, and these indications of cell injury can be prevented by addition of a cell-permeant protease inhibitor. Our findings indicate that caerulein-induced intra-acinar cell activation of trypsinogen depends on a rise in intracellular Ca2+, which reflects entry of Ca2+from the suspending medium. Intra-acinar cell activation of trypsinogen is an early as well as a critical event in pancreatitis. The subsequent cell injury in this model is mediated by activated proteases.

scholarly journals Zymogen activation in a reconstituted pancreatic acinar cell system

2006 ◽  
Vol 290 (5) ◽  
pp. G894-G902 ◽  
Author(s):  
Edwin C. Thrower ◽  
Alexander P. E. Diaz de Villalvilla ◽  
Thomas R. Kolodecik ◽  
Fred S. Gorelick
Keyword(s):  
Acute Pancreatitis ◽  
Acinar Cell ◽  
Cathepsin B ◽  
Cell System ◽  
Pancreatic Acinar Cell ◽  
In Vivo Model ◽  
Zymogen Granule ◽  
Zymogen Activation

Pathological activation of digestive zymogens within the pancreatic acinar cell initiates acute pancreatitis. Cytosolic events regulate this activation within intracellular compartments of unclear identity. In an in vivo model of acute pancreatitis, zymogen activation was detected in both zymogen granule-enriched and microsomal cellular fractions. To examine the mechanism of this activation in vitro, a reconstituted system was developed using pancreatic cytosol, a zymogen granule-enriched fraction, and a microsomal fraction. Addition of cytosol to either particulate fraction resulted in a prominent increase in both trypsin and chymotrypsin activities. The percentage of the pool of trypsinogen and chymotrypsinogen activated was about twofold and sixfold greater, respectively, in the microsomal than in the zymogen granule-enriched fraction. Activation of chymotrypsinogen but not trypsinogen was significantly enhanced by ATP (5 mM) but not by the inactive ATP analog AMP-PNP. The processing of procarboxypeptidase B to its mature form also demonstrated a requirement for ATP and cytosol. E64d, an inhibitor of cathepsin B, a thiol protease that can activate trypsin, completely inhibited trypsin activity but did not affect chymotrypsin activity or carboxypeptidase B generation. These studies demonstrate that both zymogen granule-enriched and microsomal fractions from the pancreas can support cytosol-dependent zymogen activation. A component of the activation of some zymogens, such as chymotrypsinogen and procarboxypeptidase, may depend on ATP but not on trypsin or cathepsin B.

Cause-effect relationships between zymogen activation and other early events in secretagogue-induced acute pancreatitis

2007 ◽  
Vol 292 (6) ◽  
pp. G1738-G1746 ◽  
Author(s):  
Gijs J. D. Van Acker ◽  
Eric Weiss ◽  
Michael L. Steer ◽  
George Perides
Keyword(s):  
Acute Pancreatitis ◽  
Transcription Factors ◽  
Acinar Cell ◽  
Cathepsin B ◽  
Cell Injury ◽  
Experimental Pancreatitis ◽  
Causal Relationships ◽  
Zymogen Activation ◽  
Lysosomal Hydrolases ◽  
Early Stages

We have hypothesized that the colocalization of digestive zymogens with lysosomal hydrolases, which occurs during the early stages of every experimental pancreatitis model, facilitates activation of those zymogens by lysosomal hydrolases such as cathepsin B and that this activation triggers acute pancreatitis by leading to acinar cell injury. Some, however, have argued that the colocalization phenomenon may be the result, rather than the cause, of zymogen activation during pancreatitis. To resolve this controversy and explore the causal relationships between zymogen activation and other early pancreatitis events, we induced pancreatitis in mice by repeated supramaximal secretagogue stimulation with caerulein. Some animals were pretreated with the cathepsin B inhibitor CA-074me to inhibit cathepsin B, prevent intrapancreatic activation of digestive zymogens, and reduce the severity of pancreatitis. We show that inhibition of cathepsin B by pretreatment with CA-074me prevents intrapancreatic zymogen activation and reduces organellar fragility, but it does not alter the caerulein-induced colocalization phenomenon or subcellular F-actin redistribution or prevent caerulein-induced activation of NF-κB, ERK1/2, and JNK or upregulated expression of cytochemokines. We conclude 1) that the colocalization phenomenon, F-actin redistribution, activation of proinflammatory transcription factors, and upregulated expression of cytochemokines are not the results of zymogen activation, and 2) that these early events in pancreatitis are not dependent on cathepsin B activity. In contrast, zymogen activation and increased subcellular organellar fragility during caerulein-induced pancreatitis are dependent on cathepsin B activity.

Dopamine D2 receptor activator quinpirole protects against trypsinogen activation during acute pancreatitis via upregulating HSP70

2020 ◽  
Vol 318 (6) ◽  
pp. G1000-G1012
Author(s):  
Xin Ye ◽  
Xiao Han ◽  
Bin Li ◽  
Juanjuan Dai ◽  
Zengkai Wu ◽  
...  
Keyword(s):  
Acute Pancreatitis ◽  
Dopamine D2 Receptor ◽  
D2 Receptor ◽  
Pancreatic Injury ◽  
Dependent Manner ◽  
Trypsinogen Activation ◽  
Mechanistic Insight ◽  
Receptor Activator

The current study demonstrated that activation of DRD2 by quinpirole protects against trypsinogen activation in the in vitro and in vivo setting of acute pancreatitis by upregulating HSP70 and restoring lysosomal degradation via a PP2A-dependent manner, therefore leading to reduced pancreatic injury. These findings provide a new mechanistic insight on the protective effect of DRD2 activation in acute pancreatitis.

scholarly journals Inflammatory Response on the Pancreatic Acinar Cell Injury

2005 ◽  
Vol 94 (2) ◽  
pp. 97-102 ◽  
Author(s):  
M. Bhatia
Keyword(s):  
Acute Pancreatitis ◽  
Inflammatory Response ◽  
Acinar Cell ◽  
Cell Injury ◽  
Critical Role ◽  
Organ Damage ◽  
Multiple Organ ◽  
Pancreatic Acinar Cell ◽  
Inflammatory Disorder ◽  
Distant Organ

Acute pancreatitis is an inflammatory disorder, and inflammation not only affects the pathogenesis but also the course of the disease. Acinar cell injury early in acute pancreatitis leads to a local inflammatory reaction; if marked this leads to a systemic inflammatory response syndrome (SIRS). An excessive SIRS leads to distant organ damage and multiple organ dysfunction syndrome (MODS). MODS associated with acute pancreatitis is the primary cause of morbidity and mortality in this condition. Recent studies by us and other investigators have established the critical role played by inflammatory mediators such as TNF-α, IL-1β, IL-6, IL-8, CINC/GRO-α, MCP-1, PAF, IL-10, CD40L, C5a, ICAM-1, MIP1-α, RANTES, substance P, and hydrogen sulfide in acute pancreatitis and the resultant MODS. This review intends to present an overview of the inflammatory response that takes place following pancreatic acinar cell injury.

scholarly journals Activation of MAIT cells plays a critical role in viral vector vaccine immunogenicity

2019 ◽  
Author(s):  
Nicholas M. Provine ◽  
Ali Amini ◽  
Lucy C. Garner ◽  
Christina Dold ◽  
Claire Hutchings ◽  
...  
Keyword(s):  
Cell Activation ◽  
Viral Vector ◽  
Critical Role ◽  
Vector Vaccine ◽  
Future Design ◽  
Mait Cells ◽  
Lethal Infection ◽  
Mait Cell

AbstractMucosal-associated invariant T (MAIT) cells can be activated by viruses through a cytokine-dependent mechanism, and thereby protect from lethal infection. Given this, we reasoned MAIT cells may have a critical role in the immunogenicity of replication-incompetent adenovirus vectors, which are novel and highly potent vaccine platforms. In vitro, ChAdOx1 (Chimpanzee Adenovirus Ox1) induced potent activation of MAIT cells. Activation required transduction of monocytes and plasmacytoid dendritic cells to produce IL-18 and IFN-α, respectively. IFN-α-induced monocyte-derived TNF-α was identified as a novel intermediate in this activation pathway, and activation required combinatorial signaling of all three cytokines. Furthermore, ChAdOx1-induced in vivo MAIT cell activation in both mice and human volunteers. Strikingly, MAIT cell activation was necessary in vivo for development of ChAdOx1-induced HCV-specific CD8 T cell responses. These findings define a novel role for MAIT cells in the immunogenicity of viral vector vaccines, with potential implications for future design.One sentence summaryRobust immunogenicity of candidate adenovirus vaccine vectors requires the activation of unconventional T cells.

Treatment with bindarit, a blocker of MCP-1 synthesis, protects mice against acute pancreatitis

2005 ◽  
Vol 288 (6) ◽  
pp. G1259-G1265 ◽  
Author(s):  
Madhav Bhatia ◽  
Raina Devi Ramnath ◽  
Lakshmi Chevali ◽  
Angelo Guglielmotti
Keyword(s):  
Acute Pancreatitis ◽  
Cell Injury ◽  
Inflammatory Diseases ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Pharmacological Intervention ◽  
Chemokine Production ◽  
Neutrophil Sequestration

Chemokines are believed to play a key role in the pathogenesis of acute pancreatitis. We have earlier shown that pancreatic acinar cells produce the chemokine monocyte chemotactic protein (MCP)-1 in response to caerulein hyperstimulation, demonstrating that acinar-derived MCP-1 is an early mediator of inflammation in acute pancreatitis. Blocking chemokine production or action is a major target for pharmacological intervention in a variety of inflammatory diseases, such as acute pancreatitis. 2-Methyl-2-[[1-(phenylmethyl)-1H-indazol-3yl]methoxy]propanoic acid (bindarit) has been shown to preferentially inhibit MCP-1 production in vitro in monocytes and in vivo without affecting the production of the cytokines IL-1, IL-6, or the chemokines IL-8, protein macrophage inflammatory-1α, and RANTES. The present study aimed to define the role of MCP-1 in acute pancreatitis with the use of bindarit. In a model of acute pancreatitis induced by caerulein hyperstimulation, prophylactic as well as therapeutic treatment with bindarit significantly reduced MCP-1 levels in the pancreas. Also, this treatment significantly protected mice against acute pancreatitis as evident by attenuated hyperamylasemia neutrophil sequestration in the pancreas (pancreatic MPO activity), and pancreatic acinar cell injury/necrosis on histological examination of pancreas sections.

Magnoliae Flos Essential Oil as an Immunosuppressant in Dendritic Cell Activation and Contact Hypersensitivity Responses

2020 ◽  
Vol 48 (03) ◽  
pp. 597-613 ◽  
Author(s):  
Chun-Hsien Chen ◽  
Hsin-Chun Chen ◽  
Wen-Te Chang ◽  
Meng-Shiou Lee ◽  
Yi-Chen Liu ◽  
...  
Keyword(s):  
Essential Oil ◽  
Cell Activation ◽  
Nasal Congestion ◽  
Critical Role ◽  
Adaptive Immune Response ◽  
Contact Hypersensitivity ◽  
Dendritic Cell Activation ◽  
Chinese Texts

Magnoliae Flos is a commonly used traditional medicinal material in Asia. It is used to treat sinusitis, nasal congestion, and hypersensitive skin. Because Magonlia Flos was described as an aromatic material in ancient Chinese texts, we hypothesized that its essential oil may be used to treat immune disorders. Dendritic cells (DCs), regarded as a major target of immunomodulators to control immune responses, play a critical role in the adaptive immune response. In this study, Magnoliae Flos essential oil (MFEO) decreased the production of the cytokines TNF-[Formula: see text], IL-6, and IL-12p70 in lipopolysaccharide (LPS)-stimulated DCs. It also suppressed the surface markers MHC II, CD80, and CD86 in LPS-stimulated DCs. Animal models demonstrated that the 2,4-Dinitro-1-fluorobenzene (DNFB) inducing a contact hypersensitivity response was inhibited following treatment with MFEO. In addition, MFEO inhibited the infiltration of T cells in the ears of DNFB-induced mice. To explore its bioactive compounds, the components of MFEO were analyzed using gas chromatography (GC) and GC-mass spectrometry. The results revealed that the major compounds in MFEO are camphor and 1,8-cineole. Additional DC bioassays confirmed that these compounds substantially suppressed cytokine production in LPS-induced DCs. Therefore, we demonstrated that MFEO exhibits an immunosuppressive effect both in vivo and in vitro, and camphor and 1,8-cineole may be the major components responsible for its immunosuppressive ability. The findings indicate that MFEO has the potential to be developed as a new immunosuppressant for excessive diseases.

A New Synthetic Protease Inhibitor, E-3123, Prevents Lysosomal and Mitochondrial Fragility in Rat Caerulein-Induced Pancreatitis

1992 ◽  
Vol 20 (3) ◽  
pp. 211-217
Author(s):  
T Hirano ◽  
T Manabe
Keyword(s):  
Molecular Weight ◽  
Acute Pancreatitis ◽  
Protease Inhibitor ◽  
Protective Effect ◽  
Malate Dehydrogenase ◽  
Cathepsin B ◽  
Exocrine Pancreas ◽  
Low Molecular Weight

The study investigated the protective effect of a new synthetic protease inhibitor, E-3123, a 4-guanidinobenzoate methanesulphonate, on the exocrine pancreas in caerulein-induced pancreatitis of rats both in vivo and in vitro. Hyperamylasaemia, pancreatic oedema and congestion of amylase, as well as cathepsin B leakage from lysosomes and malate dehydrogenase leakage from mitochondria, were prevented by infusion of 5 mg/kg.h E-3123 particularly when infused for 2 h before and during 5 μg/kg.h caerulein infusion for 3.5 h. The results indicate that E-3123 plays its protective roles against pancreatitis in the subcellular compartments such as lysosomes and mitochondria, and that such a low molecular weight protease inhibitor as E-3123 may be clinically useful in the treatment of acute pancreatitis.

Poly I:C-based rHBVvac therapeutic vaccine eliminates HBV via generation of HBV-specific CD8+ effector memory T cells

Gut ◽  
2019 ◽  
Vol 68 (11) ◽  
pp. 2032-2043 ◽  
Author(s):  
Hua-Jun Zhao ◽  
Qiu-Ju Han ◽  
Guan Wang ◽  
Ang Lin ◽  
Dong-Qing Xu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell Activation ◽  
Cell Activation ◽  
Critical Role ◽  
Therapeutic Vaccine ◽  
Poly I:C ◽  
Effector Memory ◽  
Potential Candidate

ObjectiveChronic hepatitis B (CHB) virus infection is a global health problem. Finding a cure for CHB remains a challenging task.DesignIn this study, poly I:C was employed as an adjuvant for HBV therapeutic vaccine (referred to as pHBV-vaccine) and the feasibility and efficiency of pHBV-vaccine in CHB treatment were evaluated in HBV-carrier mice.ResultsWe found that pHBV-vaccine decreased HBsAg and HBV DNA efficiently and safely in HBV-carrier mice. Further investigation showed that pHBV-vaccine promoted maturation and antigen presentation ability of dendritic cells in vivo and in vitro. This vaccine successfully restored the exhaustion of antigen-specific CD8+ T cells and partly broke the immune tolerance established in HBV-carrier mice. pHBV-vaccine also enhanced the proliferation and polyfunctionality of HBV-specific CD11ahi CD8αlo cells. Importantly, we observed that T cell activation molecule KLRG1 was only expressed on HBV specific CD11ahi CD8αlo cells. Furthermore, pHBV-vaccine reduced the expression of Eomes and increased the serum IL-12 levels, which in turn promoted the generation of effector memory short-lived effector cells (SLECs) to exhibit a critical role in HBV clearance. SLECs induced by pHBV-vaccine might play a crucial role in protecting from HBV reinfection.ConclusionsFindings from this study provide a new basis for the development of therapeutic pHBV-vaccine, which might be a potential candidate for clinical CHB therapy.

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