| 1. |
- Linders, Johan, et al.
(författare)
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Complement Component 3 Is Required for Tissue Damage, Neutrophil Infiltration, and Ensuring NET Formation in Acute Pancreatitis
- 2020
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 61:6, s. 163-176
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Neutrophil extracellular traps (NETs) are known to play an important role in the pathophysiology of acute pancreatitis (AP). Activation of the complement cascade has been shown to occur in AP. The aim of this study was to examine whether complement component 3 is involved in the generation of NETs in AP.METHODS: AP was induced in wild-type and C3-deficient mice by retrograde infusion of taurocholate into the pancreatic duct. Blood, lung, and pancreas tissue were collected and MPO activity was determined in lung and pancreas tissue. Histological examination of the inflamed pancreas was performed. Plasma levels of CXCL2, MMP-9, IL-6, and DNA-histone complexes as well as pancreatic levels of CXCL1 and CXCL2 were determined by use of enzyme-linked immunosorbent assay. NETs were detected in the pancreas by electron microscopy. The amount of MPO and citrullinated histone 3 in neutrophils isolated from bone marrow was examined using flow cytometry.RESULTS: In C3-deficient mice, challenge with taurocholate yielded much fewer NETs in the pancreatic tissue compared with wild-type controls. Taurocholate-induced blood levels of amylase, tissue injury, and neutrophil recruitment in the pancreas were markedly reduced in the mice lacking C3. Furthermore, MPO levels in the lung, and plasma levels of IL-6, MMP-9, and CXCL2 were significantly lower in the C3-deficient mice compared to wild-type mice after the induction of AP. In vitro studies revealed that neutrophils from C3-deficient mice had normal NET-forming ability and recombinant C3a was not capable of directly inducing NETs formation in the wild-type neutrophils.CONCLUSION: C3 plays an important role in the pathophysiology of AP as it is necessary for the recruitment of neutrophils into the pancreas and ensuring NETs formation. Targeting C3 could hence be a potential strategy to ameliorate local damage as well as remote organ dysfunction in AP.
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| 2. |
- Linders, Johan, et al.
(författare)
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Extracellular cold-inducible RNA-binding protein regulates neutrophil extracellular trap formation and tissue damage in acute pancreatitis
- 2020
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Ingår i: Laboratory Investigation. - : Elsevier BV. - 0023-6837. ; 100:12, s. 1618-1630
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Tidskriftsartikel (refereegranskat)abstract
- Neutrophil extracellular traps (NETs) play a key role in the development of acute pancreatitis (AP). In the present study, we studied the role of extracellular cold-inducible RNA-binding protein (eCIRP), a novel damage-associated-molecular-pattern molecule, in severe AP. C57BL/6 mice underwent retrograde infusion of taurocholate into the pancreatic duct. C23, an eCIRP inhibitor, was given 1 h prior to induction of AP. Pancreatic, lung, and blood samples were collected and levels of citrullinated histone 3, DNA-histone complexes, eCIRP, myeloperoxidase (MPO), amylase, cytokines, matrix metalloproteinase-9 (MMP-9), and CXC chemokines were quantified after 24 h. NETs were detected by electron microscopy in the pancreas and bone marrow-derived neutrophils. Amylase secretion was analyzed in isolated acinar cells. Plasma was obtained from healthy individuals and patients with mild and moderate severe or severe AP. Taurocholate infusion induced NET formation, inflammation, and tissue injury in the pancreas. Pretreatment with C23 decreased taurocholate-induced pancreatic and plasma levels of eCIRP and tissue damage in the pancreas. Blocking eCIRP reduced levels of citrullinated histone 3 and NET formation in the pancreas as well as DNA-histone complexes in the plasma. In addition, administration of C23 attenuated MPO levels in the pancreas and lung of mice exposed to taurocholate. Inhibition of eCIRP reduced pancreatic levels of CXC chemokines and plasma levels of IL-6, HMGB-1, and MMP-9 in mice with severe AP. Moreover, eCIRP was found to be bound to NETs. Coincubation with C23 reduced NET-induced amylase secretion in isolated acinar cells. Patients with severe AP had elevated plasma levels of eCIRP compared with controls. Our novel findings suggest that eCIRP is a potent regulator of NET formation in the inflamed pancreas. Moreover, these results show that targeting eCIRP with C23 inhibits inflammation and tissue damage in AP. Thus, eCIRP could serve as an effective target to attenuate pancreatic damage in patients with AP.
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| 3. |
- Madhi, Raed, et al.
(författare)
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c-Abl kinase regulates neutrophil extracellular trap formation, inflammation, and tissue damage in severe acute pancreatitis
- 2019
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Ingår i: Journal of Leukocyte Biology. - 0741-5400. ; 106:2, s. 455-466
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Tidskriftsartikel (refereegranskat)abstract
- Neutrophil extracellular traps (NETs) are involved in acute pancreatitis (AP) but mechanisms controlling NET expulsion in AP are incompletely understood. Herein, we examined the role of c-Abelson (c-Abl) kinase in NET formation and tissue damage in severe AP. AP was induced by taurocholate infusion into pancreatic duct or intraperitoneal administration of l-arginine in mice. Pancreatic, lung, and blood samples were collected and levels of phosphorylated c-Abl kinase, citrullinated histone 3, DNA-histone complexes, myeloperoxidase, amylase, cytokines, and CXC chemokines were quantified. Citrullinated histone 3, reactive oxygen species (ROS), and NET formation were determined in bone marrow neutrophils. Taurocholate challenge increased phosphorylation of c-Abl kinase and levels of citrullinated histone 3 in the pancreas as well as DNA-histone complexes in the plasma. Administration of the c-Abl kinase inhibitor GZD824 not only abolished activation of c-Abl kinase but also decreased levels of citrullinated histone 3 in the pancreas and DNA-histone complexes in the plasma of animals with AP. Moreover, GZD824 decreased plasma levels of amylase, IL-6, and MMP-9 as well as edema, acinar cell necrosis, hemorrhage, CXC chemokine formation, and neutrophil infiltration in the inflamed pancreas. A beneficial effect of c-Abl kinase inhibition was confirmed in l-arginine-induced pancreatitis. In vitro, inhibition of c-Abl kinase reduced TNF-α-induced formation of ROS, histone 3 citrullination, and NETs in isolated bone marrow neutrophils. Our findings demonstrate that c-Abl kinase regulates NET formation in the inflamed pancreas. In addition, inhibition of c-Abl kinase reduced pancreatic tissue inflammation, and damage in AP. Thus, targeting c-Abl kinase might be a useful way to protect the pancreas in severe AP.
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| 4. |
- Madhi, Raed, et al.
(författare)
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Targeting peptidylarginine deiminase reduces neutrophil extracellular trap formation and tissue injury in severe acute pancreatitis
- 2019
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Ingår i: Journal of Cellular Physiology. - : Wiley. - 0021-9541 .- 1097-4652. ; 234:7, s. 11850-11860
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Tidskriftsartikel (refereegranskat)abstract
- Recent evidence suggests that neutrophil extracellular traps (NETs) play an important role in the development of acute pancreatitis (AP). Herein, we examined the role of peptidylarginine deiminase (PAD), which has been shown to regulate NET formation, in severe AP. AP was induced by retrograde of taurocholate infusion into pancreatic duct in C57BL/6 mice. PAD was pharmacologically inhibited using Cl-amidine, a pan-PAD inhibitor. Pancreata were collected, and histones, citrullinated histone 3, chemokines, myeloperoxidase, and NETs were quantified. Chemokines, matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and DNA-histone complexes were determined in plasma samples. Infusion of taurocholate induced formation of NETs in pancreatic tissues of mice. Pretreatment with Cl-amidine markedly reduced the NET formation in the inflamed pancreas. Moreover, inhibition of PAD decreased the levels of blood amylase as well as edema, acinar cell necrosis, hemorrhage, and neutrophil infiltration in the pancreas of animals with AP. Administration of Cl-amidine attenuated the myeloperoxidase levels in the pancreas and lung of mice exposed to taurocholate. In addition, Cl-amidine decreased pancreatic levels of CXC chemokines, plasma levels of IL-6, and MMP-9 in mice with severe AP. This study shows that Cl-amidine is a potent inhibitor of NET formation in severe AP. Also, our results suggest that PAD regulates pathological inflammation and tissue damage in the inflamed pancreas. Thus, targeting PAD might be a useful strategy to treat patients with severe AP.
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| 5. |
- Merza, Mohammed, et al.
(författare)
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Neutrophil Extracellular Traps Induce Trypsin Activation, Inflammation, and Tissue Damage in Mice with Severe Acute Pancreatitis.
- 2015
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Ingår i: Gastroenterology. - : Elsevier BV. - 1528-0012 .- 0016-5085. ; 149:7, s. 1920-1920
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Tidskriftsartikel (refereegranskat)abstract
- Neutrophils are involved in development of acute pancreatitis (AP), but it is not clear how neutrophil-induced tissue damage is regulated. In addition to secreting antimicrobial compounds, activated neutrophils eliminate invading microorganisms by expelling nuclear DNA and histones to form extracellular web-like structures called neutrophil extracellular traps (NETs). However, NETs have been reported contribute to organ dysfunction in patients with infectious diseases. We investigated whether NETs contribute to development of AP in mice.
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