| 11. |
- Awla, Darbaz, et al.
(författare)
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Rho-kinase signalling regulates trypsinogen activation and tissue damage in severe acute pancreatitis.
- 2011
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Ingår i: British Journal of Pharmacology. - : Wiley. - 1476-5381 .- 0007-1188. ; 162, s. 648-658
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Tidskriftsartikel (refereegranskat)abstract
- Background and purpose: Severe acute pancreatitis (SAP) is characterized by trypsinogen activation, infiltration of leucocytes and tissue necrosis but the intracellular signalling mechanisms regulating organ injury in the pancreas remain elusive. Rho-kinase is a potent regulator of specific cellular processes effecting several pro-inflammatory activities. Herein, we examined the role of Rho-kinase signalling in acute pancreatitis. Experimental approach: Pancreatitis was induced by infusion of taurocholate into the pancreatic duct in C57BL/6 mice. Animals were treated with a Rho-kinase inhibitor Y-27632 (0.5-5 mg kg(-1) ) before induction of pancreatitis. Key results: Taurocholate infusion caused a clear-cut increase in serum amylase, pancreatic neutrophil infiltration, acinar cell necrosis and oedema formation in the pancreas. Levels of pancreatic myeloperoxidase (MPO), macrophage inflammatory protein-2 (MIP-2), trypsinogen activation peptide (TAP) and lung MPO were significantly increased, indicating local and systemic disease. Inhibition of Rho-kinase activity dose-dependently protected against pancreatitis. For example, 5 mg kg(-1) Y-27632 reduced acinar cell necrosis, leucocyte infiltration and pancreatic oedema by 90%, 89% and 58% respectively as well as tissue levels of MPO by 75% and MIP-2 by 84%. Moreover, Rho-kinase inhibition decreased lung MPO by 75% and serum amylase by 83%. Pancreatitis-induced TAP levels were reduced by 61% in Y-27632-treated mice. Inhibition of Rho-kinase abolished secretagogue-induced activation of trypsinogen in pancreatic acinar cells in vitro. Conclusions and Implications: Our novel data suggest that Rho-kinase signalling plays an important role in acute pancreatitis by regulating trypsinogen activation and subsequent CXC chemokine formation, neutrophil infiltration and tissue injury. Thus, these results indicate that Rho-kinase may constitute a novel target in the management of SAP.
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| 12. |
- Awla, Darbaz, et al.
(författare)
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TLR4 but not TLR2 regulates inflammation and tissue damage in acute pancreatitis induced by retrograde infusion of taurocholate.
- 2011
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Ingår i: Inflammation Research. - : Springer Science and Business Media LLC. - 1420-908X .- 1023-3830. ; 60, s. 1093-1098
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Neutrophil infiltration is a key regulator in the pathophysiology of acute pancreatitis (AP), although the impact of Toll-like receptors (TLRs) in AP remains elusive. The aim of this study was to define the role of TLR2 and TLR4 in leukocyte recruitment and tissue damage in severe AP. EXPERIMENTAL DESIGN: AP was induced by retrograde infusion of sodium taurocholate into the pancreatic duct in wild-type, TLR2- and TLR4-deficient mice. Samples were collected 24 h after induction of AP. RESULTS: Taurocholate challenge caused a clear-cut pancreatic damage characterized by increased acinar cell necrosis, neutrophil infiltration, focal hemorrhage and edema formation, as well as increased levels of blood amylase and CXCL2 (macrophage inflammatory protein-2) in the pancreas and serum. Moreover, challenge with taurocholate increased activation of trypsinogen in the pancreas. Notably, TLR2 gene-deficient mice exhibited a similar phenotype to wild-type mice after challenge with taurocholate. In contrast, tissue damage, pancreatic and lung myeloperoxidase (MPO) activity, serum and pancreatic levels of CXCL2 as well as blood amylase were significantly reduced in TLR4-deficient mice exposed to taurocholate. However, taurocholate-induced activation of trypsinogen was intact in TLR4-deficient mice. CONCLUSION: Our data suggest a role for TLR4 but not TLR2 in the pathogenesis of severe AP in mice.
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| 13. |
- Changhui, Yu, et al.
(författare)
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Rac1 signaling regulates neutrophil-dependent tissue damage in experimental colitis.
- 2014
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Ingår i: European Journal of Pharmacology. - : Elsevier BV. - 1879-0712 .- 0014-2999. ; 741:Jul 30, s. 90-96
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Tidskriftsartikel (refereegranskat)abstract
- Excessive neutrophil recruitment in the colon is a major feature in acute colitis although the signaling mechanisms behind colonic recruitment of neutrophils remain elusive. Herein, we hypothesized that Rac1 activity might play an important role in neutrophil infiltration in the inflamed colon. Female Balb/c mice were treated with the Rac1 inhibitor NSC23766 (0.5 and 5mg/kg) before and daily after administration of 5% dextran sodium sulfate (DSS). Colonic tissue was collected for quantification of neutrophil recruitment, interleukin-6 (IL-6) and CXC chemokine formation as well as histological damage score five days after challenge with DSS. Rac1 activity was determined by western blot and Mac-1 expression by flow cytometry in neutrophils. Administration of NSC23766 decreased DSS-induced neutrophil recruitment and tissue damage in the colon. Rac1 inhibition decreased colonic formation of IL-6 and CXC chemokines in experimental colitis. Chemokine challenge increased Rac1 activity in neutrophils and NSC23766 markedly reduced this neutrophil activity of Rac1. Inhibition of Rac1 abolished CXC chemokine-induced neutrophil chemotaxis and up-regulation of Mac-1 in vitro. Taken together, Rac1 signaling plays a significant role in controlling accumulation of neutrophils and tissue injury in experimental colitis. Thus, our novel results suggest that targeting Rac1 signaling might be a useful way to protect against neutrophil-mediated tissue injury in acute colitis.
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| 14. |
- Chew, Michelle, et al.
(författare)
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Increased plasma levels of heparin-binding protein in patients with shock: a prospective, cohort study.
- 2012
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Ingår i: Inflammation Research. - : Springer Science and Business Media LLC. - 1420-908X .- 1023-3830. ; 61:4, s. 375-379
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Heparin-binding protein (HBP) is a potent inducer of increased vascular permeability. The purpose of this study was to examine plasma levels of HBP in patients with shock. DESIGN: Fifty-three consecutive patients with septic and non-septic shock at a mixed-bed intensive care unit were included, as well as 20 age-matched controls. Patients with local infections but without signs of shock served as infectious controls. Enzyme-linked immunosorbent assay was used to determine plasma levels of HBP. RESULTS: There were no differences in serum HBP levels between healthy controls and those with local infections, including urinary tract infections, pneumonia and gastroenteritis, without shock. Levels of HBP were higher in patients with non-septic shock and septic shock than healthy controls. However, there was no difference in serum HBP levels between patients with septic shock and those with non-septic shock. Moreover, HBP levels were not different between patients with low and high APACHE II scores. Plasma levels of HBP were similar in surviving and non-surviving patients with shock. CONCLUSIONS: HBP is elevated in patients with shock from septic and non-septic etiologies. Future investigations are required to define the functional role of HBP in patients with shock.
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| 15. |
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| 16. |
- Chew, Michelle, et al.
(författare)
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Soluble CD40L (CD154) is increased in patients with shock.
- 2010
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Ingår i: Inflammation Research. - : Springer Science and Business Media LLC. - 1420-908X .- 1023-3830. ; 59, s. 979-982
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Recent data suggest that soluble CD40L (sCD40L) plays an important role in murine sepsis. The aim of the present study was to determine plasma levels of CD40L in critically ill patients with systemic inflammatory response syndrome (SIRS) and shock, with and without sepsis. DESIGN: A prospective observational one-centre cohort study in a mixed-bed ICU of an university hospital. Fifty-three consecutive patients fulfilling the criteria for SIRS with shock as well as seven age-matched controls were included. ELISA was used to determine sCD40L in the plasma. RESULTS: The level of sCD40L in plasma from healthy controls was 0.18 +/- 0.03 ng/ml. It was found that sCD40L levels were significantly higher in patients with non-septic shock (0.72 +/- 0.18 ng/ml) and septic shock (0.50 +/- 0.1 ng/ml). However, the levels of sCD40L were not different between these two groups of patients, or in those with low and high APACHE scores. CONCLUSION: Our data show that sCD40L is increased in patients with shock from septic and non-septic etiologies. However, further studies are needed to delineate the functional significance of sCD40L in the clinical outcome in shock patients.
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| 17. |
- Dold, Stefan, et al.
(författare)
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P-selectin glycoprotein ligand-1-mediated leukocyte recruitment regulates hepatocellular damage in acute obstructive cholestasis in mice.
- 2010
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Ingår i: Inflammation Research. - : Springer Science and Business Media LLC. - 1420-908X .- 1023-3830. ; 59, s. 291-298
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Leukocytes mediate hepatocellular injury in obstructive cholestasis. The aim of the present study was to define the role of P-selectin glycoprotein ligand-1 (PSGL-1) in cholestasis-induced leukocyte recruitment and liver damage. METHODS: C57BL/6 mice were pre-treated with an anti-PSGL-1 antibody or a control antibody prior to bile duct ligation (BDL) for 12 h. Hepatic recruitment of leukocytes and sinusoidal perfusion were determined by means of intravital fluorescence microscopy. Liver damage was monitored by measuring serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Hepatic levels of CXC chemokines were determined by ELISA. RESULTS: BDL caused significant hepatocellular damage indicated by increased serum activities of ALT and AST as well as decreased sinusoidal perfusion and clear-cut hepatic infiltration of leukocytes. Administration of the anti-PSGL-1 antibody reduced BDL-induced levels of ALT by 78% and AST by 77%. Inhibition of PSGL-1 decreased BDL-provoked leukocyte rolling and adhesion in post-sinusoidal venules by more than 81%. Moreover, we found that immunoneutralisation of PSGL-1 restored sinusoidal perfusion and decreased hepatic formation of CXC chemokines in cholestatic mice. CONCLUSIONS: Our novel data show that PSGL-1 plays an important role in cholestatic liver damage by regulating leukocyte rolling in post-sinusoidal venules. Consequently, interference with PSGL-1 attenuates cholestasis-provoked leukocyte adhesion and extravasation in the liver. Thus, inhibition of PSGL-1 may help to protect against hepatocellular damage in cholestatic diseases.
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| 18. |
- Grape, T, et al.
(författare)
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Primary gastroduodenal amyloidosis
- 2011
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Ingår i: Endoscopy. - : Georg Thieme Verlag KG. - 1438-8812 .- 0013-726X. ; 43, s. 288-288
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 19. |
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| 20. |
- Hartman Magnusson, Hannes, et al.
(författare)
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P-selectin mediates neutrophil rolling and recruitment in acute pancreatitis
- 2012
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Ingår i: British Journal of Surgery. - : Oxford University Press (OUP). - 0007-1323 .- 1365-2168. ; 99, s. 246-255
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Tidskriftsartikel (refereegranskat)abstract
- Background: The adhesive mechanisms regulating leucocyte-endothelium interactions in the pancreas remain elusive, but selectins may play a role. This study examined the molecular mechanisms mediating leucocyte rolling along the endothelium in the pancreas and the therapeutic potential of targeting the rolling adhesive interaction in acute pancreatitis (AP). Methods: Pancreatitis was induced by retrograde infusion of 5 per cent sodium taurocholate into the pancreatic duct, repeated intraperitoneal administration of caerulein (50 μg/kg) or intraperitoneal administration of L-arginine (4 g/kg) in C57BL/6 mice. A control and a monoclonal antibody against P-selectin were administered before and after induction of AP. Serum and tissue were sampled to assess the severity of pancreatitis, and intravital microscopy was used to study leucocyte rolling. Results: Taurocholate infusion into the pancreatic duct increased the serum level of trypsinogen, trypsinogen activation, pancreatic neutrophil infiltration, macrophage inflammatory protein (MIP) 2 formation and tissue damage. Immunoneutralization of P-selectin decreased the taurocholate-induced increase in serum trypsinogen (median (range) 17·35 (12·20- 30·00) versus 1·55 (0·60-15·70) μg/l; P = 0·017), neutrophil accumulation (4·00 (0·75-4·00) versus 0·63 (0-3·25); P = 0·002) and tissue damage, but had no effect on MIP-2 production (14·08 (1·68-33·38) versus 3·70 (0·55-51·80) pg/mg; P = 0·195) or serum trypsinogen activating peptide level (1·10 (0·60-1·60) versus 0·45 (0-1·80) μg/l; P = 0·069). Intravital fluorescence microscopy revealed that anti-P-selectin antibody inhibited leucocyte rolling completely in postcapillary venules of the inflamed pancreas. Conclusion: Inhibition of P-selectin protected against pancreatic tissue injury in experimental pancreatitis. Targeting P-selectin may be an effective strategy to ameliorate inflammation in AP. © 2011 British Journal of Surgery Society Ltd.
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