Emodin attenuates severe acute pancreatitis-associated acute lung injury by suppressing pancreatic exosome-mediated alveolar macrophage activation

Background—Interleukin 8 (IL-8) has recently been proposed to have an important role in mediating the development of the systemic sequelae associated with severe acute pancreatitis.Aims—To define the role of IL-8 in acute pancreatitis by neutralising its effects with a monoclonal anti-IL-8 antibody (WS-4), in a rabbit model of severe acute pancreatitis.Methods—Acute pancreatitis was induced by retrograde injection of 5% chenodeoxycholic acid into the pancreatic duct and duct ligation. Twenty rabbits were divided equally into two groups: acute pancreatitis controls received physiological saline and the treated group received WS-4, 30 minutes before induction of acute pancreatitis.Results—Pretreatment of animals with WS-4 resulted in significant down regulation of serum IL-8 and tumour necrosis factor α (TNF-α) from three to six hours after induction of acute pancreatitis (p=0.011 and 0.047 for IL-8 and 0.033 and 0.022 for TNF-α, respectively). In addition, a significant reduction in the CD11b and CD18 positive cells and the amount of interstitial neutrophil infiltration in the lungs from WS-4 treated animals was seen. In contrast, WS-4 did not alter the amount of pancreatic necrosis and the serum concentrations of amylase, lipase, calcium, and glucose.Conclusion—WS-4 cannot change the amount of pancreatic necrosis induced by injection of 5% bile acid, but does reduce the acute lung injury, presumably through inhibition of circulating IL-8 and TNF-α, and CD11b/CD18 in lung tissue. Therefore, a role of IL-8 in the progression of acute pancreatitis and the development of its systemic complications is suggested.

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Mesenchymal Stem Cells Attenuate Acute Lung Injury in Mice Partly by Suppressing Alveolar Macrophage Activation in a PGE2-dependent Manner

10.21203/rs.3.rs-664786/v1 ◽

2021 ◽

Author(s):

Gaojian Wang ◽

Yaping Zhang ◽

Nianqiang Hu ◽

Qinxue Liu ◽

Fengjie Ma ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Alveolar Macrophage ◽

Alveolar Macrophages ◽

Macrophage Activation ◽

Rna Seq ◽

Ep4 Receptor ◽

Pge2 Receptor ◽

Cox2 Inhibitor

Abstract Background: Mesenchymal stem cell have shown therapeutic effect on acute lung injury, MSC could be activated when added to inflammatory environment and in turn suppress inflammation, yet the mechanism is complex and not understood. Methods: To determine the effect of MSC on ALI and alveolar macrophage activation, MSCs were administered to ALI mice and co-cultured with activated MH-S cells (alveolar macrophage cell line). To find the genes critical for MSC’s immunosuppressive effects, rest and activated MSCs induced by inflammatory MH-S cells were harvested for RNA-seq. To prove that PGE2 participates in the immunosuppressive effects of MSC, COX2 inhibitor and PGE2 receptor antagonist were added to the co-culture system and administrated to ALI mice. Results: The intratracheal administration of MSCs attenuated ALI and suppressed alveolar macrophages activation in vivo, the activation of MH-S cells was also significantly reduced after co-culturing with MSCs in vitro. The RNA-seq data of rest and activated MSCs suggested that the Ptgs2 gene may play an important role in MSC exerting immunosuppressive effects. Correspondingly, we found that the COX2 protein and PGE2 released by activated MSCs were increased dramatically after co-culturing with MH-S. The use of COX2 inhibitor NS-398 restrained the secretion of PGE2 and reversed the suppressive effect on macrophages activation of MSCs in vitro. Furthermore, GW627368X, a selective antagonist of PGE2 receptor (EP4 receptor), also reversed the inhibitory effects of MSCs on alveolar macrophages and their protective effects on ALI mice.Conclusions: MSC attenuate ALI partly through suppressing alveolar macrophage activation via PGE2 binding to EP4 receptor.

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Pathophysiological aspects of severe acute pancreatitis-associated lung injury

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh0502076s ◽

2005 ◽

Vol 133 (1-2) ◽

pp. 76-81 ◽

Cited By ~ 13

Author(s):

Maja Surbatovic ◽

Krsta Jovanovic ◽

Sonja Radakovic ◽

Nikola Filipovic

Keyword(s):

Acute Pancreatitis ◽

Acute Lung Injury ◽

Mortality Rate ◽

Lung Injury ◽

Severe Acute Pancreatitis ◽

Distress Syndrome ◽

Severe Form ◽

Very High ◽

Intensive Medicine

Acute pancreatitis is an inflammatory process which occurs in severe form in 20% of all patients, out of whom 1596-25% will die. The incidence of severe acute pancreatitis-associated lung injury (APALI) varies from 15% to 55% and its severity varies from mild hypoxemia to acute respiratory distress syndrome (ARDS). Acute lung injury (ALI) and ARDS are the most significant manifestations of extra abdominal dysfunctions in severe acute pancreatitis with mortality rate as high as 60% in the first week of the onset of illness. Different pathophysiological mechanisms of severe acute pancreatitis-associated lung injury have been described. The role of enzymes, adhesion molecules, neutrophils, fibronectin and various inflammatory mediators has been emphasized. Mechanism of the acute lung injury associated with the acute pancreatitis is very complex and has not been clear yet. There is no specific therapeutic procedure and mortality rate is very high. Therefore, further studies are necessary to address this acute and growing problem in intensive medicine.

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