scholarly journals Synergistic effect of the TLR5 agonist CBLB502 and its downstream effector IL-22 against liver injury

2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Nicolas Melin ◽  
Daniel Sánchez-Taltavull ◽  
René Fahrner ◽  
Adrian Keogh ◽  
Michel Dosch ◽  
...  
Keyword(s):  
Liver Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Isolated Hepatocytes ◽  
Protective Mechanism ◽  
Mesenteric Lymph Nodes ◽  
Transcriptional Signature ◽  
Stat3 Signaling ◽  
Toll Like Receptor 5

AbstractThe toll-like receptor 5 (TLR5) agonist, CBLB502/Entolimod, is a peptide derived from bacterial flagellin and has been shown to protect against radiation-induced tissue damage in animal models. Here we investigated the protective mechanism of CBLB502 in the liver using models of ischemia-reperfusion injury and concanavalin A (ConA) induced immuno-hepatitis. We report that pretreatment of mice with CBLB502 provoked a concomitant activation of NF-κB and STAT3 signaling in the liver and reduced hepatic damage in both models. To understand the underlying mechanism, we screened for cytokines in the serum of CBLB502 treated animals and detected high levels of IL-22. There was no transcriptional upregulation of IL-22 in the liver, rather it was found in extrahepatic tissues, mainly the colon, mesenteric lymph nodes (MLN), and spleen. RNA-seq analysis on isolated hepatocytes demonstrated that the concomitant activation of NF-κB signaling by CBLB502 and STAT3 signaling by IL-22 produced a synergistic cytoprotective transcriptional signature. In IL-22 knockout mice, the loss of IL-22 resulted in a decrease of hepatic STAT3 activation, a reduction in the cytoprotective signature, and a loss of hepatoprotection following ischemia-reperfusion-induced liver injury. Taken together, these findings suggest that CBLB502 protects the liver by increasing hepatocyte resistance to acute liver injury through the cooperation of TLR5-NF-κB and IL-22-STAT3 signaling pathways.

scholarly journals SS-31 Protects Liver from Ischemia-Reperfusion Injury via Modulating Macrophage Polarization

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Longcheng Shang ◽  
Haozhen Ren ◽  
Shuai Wang ◽  
Hanyi Liu ◽  
Anyin Hu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Liver Injury ◽  
Reperfusion Injury ◽  
Liver Damage ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Macrophage Polarization ◽  
Protective Effects ◽  
Inflammation Response ◽  
Stat3 Signaling

Ischemia-reperfusion injury (IRI) is a common complication in liver surgeries. It is a focus to discover effective treatments to reduce ischemia-reperfusion injury. Previous studies show that oxidative stress and inflammation response contribute to the liver damage during IRI. SS-31 is an innovated mitochondrial-targeted antioxidant peptide shown to scavenge reactive oxygen species and decrease oxidative stress, but the protective effects of SS-31 against hepatic IRI are not well understood. The aim of our study is to investigate whether SS-31 could protect the liver from damages induced by IRI and understand the protective mechanism. The results showed that SS-31 treatment can significantly attenuate liver injury during IRI, proved by HE staining, serum ALT/AST, and TUNEL staining which can assess the degree of liver damage. Meanwhile, we find that oxidative stress and inflammation were significantly suppressed after SS-31 administration. Furthermore, the mechanism revealed that SS-31 can directly decrease ROS production and regulate STAT1/STAT3 signaling in macrophages, thus inhibiting macrophage M1 polarization. The proinflammation cytokines are then significantly reduced, which suppress inflammation response in the liver. Taken together, our study discovered that SS-31 can regulate macrophage polarization through ROS scavenging and STAT1/STAT3 signaling to ameliorate liver injury; the protective effects against hepatic IRI suggest that SS-31 may be an appropriate treatment for liver IRI in the clinic.

scholarly journals Cardiotrophin-1 defends the liver against ischemia-reperfusion injury and mediates the protective effect of ischemic preconditioning

2006 ◽  
Vol 203 (13) ◽  
pp. 2809-2815 ◽  
Author(s):  
Maria Iñiguez ◽  
Carmen Berasain ◽  
Eduardo Martinez-Ansó ◽  
Matilde Bustos ◽  
Puri Fortes ◽  
...  
Keyword(s):  
Blood Flow ◽  
Liver Injury ◽  
Protective Effect ◽  
Ischemic Preconditioning ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Isolated Hepatocytes ◽  
Survival Pathways ◽  
Stat3 Phosphorylation ◽  
Deficient Mice

Ischemia-reperfusion (I/R) liver injury occurs when blood flow is restored after prolonged ischemia. A short interruption of blood flow (ischemic preconditioning [IP]) induces tolerance to subsequent prolonged ischemia through ill-defined mechanisms. Cardiotrophin (CT)-1, a cytokine of the interleukin-6 family, exerts hepatoprotective effects and activates key survival pathways like JAK/STAT3. Here we show that administration of CT-1 to rats or mice protects against I/R liver injury and that CT-1–deficient mice are exceedingly sensitive to this type of damage. IP markedly reduced transaminase levels and abrogated caspase-3 and c-Jun–NH2-terminal kinase activation after I/R in normal mice but not in CT-1–null mice. Moreover, the protective effect afforded by IP was reduced by previous administration of neutralizing anti–CT-1 antibody. Prominent STAT3 phosphorylation in liver tissue was observed after IP plus I/R in normal mice but not in CT-1–null mice. Oxidative stress, a process involved in IP-induced hepatoprotection, was found to stimulate CT-1 release from isolated hepatocytes. Interestingly, brief ischemia followed by short reperfusion caused mild serum transaminase elevation and strong STAT3 activation in normal and IL-6–deficient mice, but failed to activate STAT3 and provoked marked hypertransaminasemia in CT-1–null animals. In conclusion, CT-1 is an essential endogenous defense of the liver against I/R and is a key mediator of the protective effect induced by IP.

Abstract 423: Proteasome Priming by Protein Kinase G Protects Against Myocardial Ischemia-reperfusion Injury

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Xuejun Wang ◽  
Erin J Terpstra ◽  
Eduardo Callegari ◽  
Chengjun Hu ◽  
Hanming Zhang ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Myocardial Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
26S Proteasome ◽  
Transgenic Mouse Line ◽  
Pde5 Inhibition ◽  
Myocardial Ischemia Reperfusion

Cardiac proteasome functional insufficiency is implicated in a large subset of heart disease and has been experimentally demonstrated to play an essential role in cardiac proteotoxicity, including desmin-related cardiomyopathy and myocardial ischemia-reperfusion (I-R) injury. Pharmacological inhibition of phosphodiesterase 5 (PDE5) via sildenafil for example, which can stabilize cGMP and thereby increase cGMP-dependent protein kinase (PKG) activity, is consistently reported to protect against I-R injury; however, the underlying mechanism is not fully understood. We have recently discovered that PKG activation enhances proteasomal degradation of misfolded proteins (Ranek, et al. Circulation 2013), prompting us to hypothesize that proteasome-priming may contribute to cardioprotection-induced by PDE5 inhibition. Here we used a cardiomyocyte-restricted proteasome inhibition transgenic mouse line (Tg) and non-Tg (Ntg) littermates to interrogate the action of sildenafil on I-R injury created by left anterior descending artery (LAD) ligation (30 min) and release (24 hr). Sildenafil was administered 30 min before LAD ligation. Results showed that (1) the 26S proteasome activity of the Ntg I-R hearts was significantly elevated by sildenafil but this elevation was blocked in the Tg line; (2) the infarct size reduction by sildenafil treatment in Ntg mice was completely abolished in the Tg mice with the same treatment; and (3) systolic and diastolic function impairment after I/R was markedly attenuated in sildenafil-treated Ntg mice, but not in the sildenafil-treated Tg mice. Additionally, immunoprecipitation assays show that PKG interacted with the proteasome in cultured cardiomyocytes, and this interaction appeared to be augmented by sildenafil treatment. Moreover, in vitro incubation of active PKG with purified human 26S proteasomes increased proteasome peptidase activities and the phosphorylation at specific serine residues of a 19S proteasome subunit as revealed by “gel-free” nano-LC-MS/MS. We conclude that active PKG directly interacts with, phosphorylates, and increases the activities of, the proteasome and that proteasome priming mediates to cardioprotection of PDE5 inhibition against I-R injury.

Zingerone Alleviates Myocardial Ischemia/Reperfusion Injury

2021 ◽  
Vol 19 (4) ◽  
pp. 543-549
Author(s):  
Fanglin Luo ◽  
Shunxiang Luo ◽  
Yanqing Wu
Keyword(s):  
Myocardial Infarction ◽  
Proinflammatory Cytokine ◽  
Myocardial Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Protective Effects ◽  
Cytokine Release ◽  
Myocardial Ischemia Reperfusion Injury ◽  
Myocardial Ischemia Reperfusion

Using a rat model, we have explored the underlying mechanism of ischemia/reperfusion (I/R)-mediated myocardial infarction and assessed the protective potential of zingerone. The results show that zingerone exhibits not only the myocardial protective effect, but also antioxidative and anti-inflammatory effects by suppression of markers of oxidation and proinflammatory cytokine release. Zingerone promotes protective effects against I/R-induced myocardial infarction by regulating Nrf2/HO-1 and NF-κB signaling pathways. These findings provide novel insights into the effects of zingerone on the cardioprotective mechanism of myocardial injury after I/R and may open new avenues for myocardial infarction treatment.

Effect of soya phosphatidylcholine and possible underlying mechanism on ischemia/reperfusion injury in isolated perfused rat heart: an experimental and computational study

2022 ◽  
pp. 1-7
Author(s):  
Anita A. Mehta ◽  
Purav Patel ◽  
Vandana R. Thakur ◽  
Jayesh V. Beladiya
Keyword(s):  
Ischemia Reperfusion Injury ◽  
Computational Study ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Left Ventricular ◽  
Global Ischemia ◽  
Mechanistic Study ◽  
Cardiac Damage ◽  
Nitric Oxide Synthase Inhibitor ◽  
Triton X

This study was designed to assess the effect of soya phosphatidylcholine (SPC) against ischemia/reperfusion (I/R) injury and the possible underlying mechanism using experimental and computational studies. I/R injury was induced by global ischemia for 30 min followed by reperfusion for 120 min. The perfusion of the SPC was performed for 10 min before inducing global ischemia. In the mechanistic study, the involvement of specific cellular pathways was identified using various inhibitors such as ATP-dependent potassium channel (KATP) inhibitor (glibenclamide), protein kinase C (PKC) inhibitor (chelerythrine), non-selective nitric oxide synthase inhibitor (L-NAME), and endothelium remover (Triton X-100). The computational study of various ligands was performed on toll-like receptor 4 (TLR4) protein using AutoDock version 4.0. SPC (100 μM) significantly decreased the levels of cardiac damage markers and %infarction compared with the vehicle control (VC). Furthermore, cardiodynamics (indices of left ventricular contraction (dp/dtmax), indices of left ventricular relaxation (dp/dtmin), coronary flow, and antioxidant enzyme levels were significantly improved as compared with VC. This protective effect was attenuated by glibenclamide, chelerythrine, and Triton X-100, but it was not attenuated by L-NAME. The computational study showed a significant bonding affinity of SPC to the TLR4-MD2 complex. Thus, SPC reduced myocardial I/R injury in isolated perfused rat hearts, which might be governed by the KATP channel, PKC, endothelium response, and TLR4-MyD88 signaling pathway.

scholarly journals Late Protective Effect of Netrin-1 in the Murine Acetaminophen Hepatotoxicity Model

2020 ◽  
Vol 175 (2) ◽  
pp. 168-181 ◽  
Author(s):  
Luqi Duan ◽  
Benjamin L Woolbright ◽  
Hartmut Jaeschke ◽  
Anup Ramachandran
Keyword(s):  
Liver Injury ◽  
Alanine Aminotransferase ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Clinical Problem ◽  
The United States ◽  
Therapeutic Window ◽  
Protective Effects ◽  
Apap Overdose ◽  
Important Clinical Problem

Abstract Acetaminophen (APAP) overdose-induced acute liver failure is an important clinical problem in the United States and the current antidote N-acetylcysteine, has a short early therapeutic window. Since most patients present late to the clinic, there is need for novel late-acting therapeutic options. Though the neuronal guidance cue netrin-1, has been shown to promote hepatic repair and regeneration during liver ischemia/reperfusion injury, its effect in APAP-induced hepatotoxicity is unknown. In the quest for a late-acting therapeutic intervention in APAP-induced liver injury, we examined the role of netrin-1 in a mouse model of APAP overdose. Male C57BL/6J mice were cotreated with exogenous netrin-1 or vehicle control, along with 300 mg/kg APAP and euthanized at 6, 12, and 24 h. Significant elevations in alanine aminotransferase indicative of liver injury were seen in control mice at 6 h and this was not affected by netrin-1 administration. Also, netrin-1 treatment did not influence mitochondrial translocation of phospho-JNK, or peroxynitrite formation indicating that there was no interference with APAP-induced injury processes. Interestingly however, netrin-1 administration attenuated liver injury at 24 h, as seen by alanine aminotransferase levels and histology, at which time significant elevations in the netrin-1 receptor, adenosine A2B receptor (A2BAR) as well as macrophage infiltration was evident. Removal of resident macrophages with clodronate liposomes or treatment with the A2BAR antagonist PSB1115 blocked the protective effects of netrin-1. Thus, our data indicate a previously unrecognized role for netrin-1 in attenuation of APAP hepatotoxicity by enhancing recovery and regeneration, which is mediated through the A2BAR and involves resident liver macrophages.

scholarly journals The Protective Effect of Total Flavones from Rhododendron simsii Planch. on Myocardial Ischemia/Reperfusion Injury and Its Underlying Mechanism

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Sheng-Yong Luo ◽  
Qing-Hua Xu ◽  
Gong Peng ◽  
Zhi-Wu Chen
Keyword(s):  
Myocardial Infarction ◽  
Protective Effect ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Assay Method ◽  
Protective Effects ◽  
Rhododendron Simsii ◽  
Rhoa Activity ◽  
Protein Expressions

Objectives. Total flavones from Rhododendron simsii Planch. (TFR) are the effective part extracted from the flowers of Rhododendron simsii Planch. and have obvious protective effects against cerebral ischemic or myocardial injuries in rabbits and rats. However, their mechanism of cardioprotection is still unrevealed. Therefore, the present study was designed to investigate the effect of TFR on myocardial I/R injury and the underlying mechanism. Methods. TFR groups were treated by gavage once a day for 3 days at a dose of 20, 40, and 80 mg/kg, respectively, and then the model of myocardial I/R injury was established. Myocardial infarction, ST-segment elevation, and the expression of UTR, ROCK1, ROCK2, and p-MLC protein in rat myocardium were determined at 90 min after reperfusion. UTR siRNA in vivo transfection and competition binding assay method were used to study the relationship between the protective effect of TFR and UTR. Results. The expression of UTR protein markedly decreased in myocardium of UTR siRNA transfection group rats. TFR could significantly reduce the infarct size and inhibit the increase of RhoA activity and ROCK1, ROCK2, and p-MLC protein expressions both in WT and UTR knockdown rats. The reducing rate of TFR in myocardial infarction area, RhoA activity, and ROCK1, ROCK2, and p-MLC protein expressions in UTR knockdown rats decreased markedly compared with that in WT rats. In addition, TFR had no obvious effect on the increase of ΣST in UTR knockdown rats in comparison with that in model group. In particular, TFR could significantly inhibit the combination of [I125]-hu-II and UTR, and IC50 was 0.854 mg/l. Conclusions. The results indicate that the protective effect of TFR on I/R injury may be correlated with its blocking UTR and the subsequent inhibition of RhoA/ROCK signaling pathway.

IS HEAT SHOCK PROTEIN A POTENTIAL PROTECTIVE MECHANISM AGAINST ISCHEMIA-REPERFUSION INJURY?

1999 ◽  
Vol 103 (1) ◽  
pp. 336-337 ◽  
Author(s):  
Sean Lille ◽  
Ching-Yuan Su ◽  
Michael Neumeister ◽  
Robert C. Russell ◽  
Chen-Ching Lai
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Protein A ◽  
Protective Mechanism

scholarly journals Endothelial STAT3 Modulates Protective Mechanisms in a Mouse Ischemia-Reperfusion Model of Acute Kidney Injury

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Shataakshi Dube ◽  
Tejasvi Matam ◽  
Jessica Yen ◽  
Henry E. Mang ◽  
Pierre C. Dagher ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Ischemia Reperfusion Injury ◽  
Leukocyte Adhesion ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Organ Injury ◽  
Mrna Levels ◽  
Kidney Dysfunction ◽  
Stat3 Signaling ◽  
Proximal Tubular

STAT3 is a transcriptional regulator that plays an important role in coordinating inflammation and immunity. In addition, there is a growing appreciation of the role STAT3 signaling plays in response to organ injury following diverse insults. Acute kidney injury (AKI) from ischemia-reperfusion injury is a common clinical entity with devastating consequences, and the recognition that endothelial alterations contribute to kidney dysfunction in this setting is of growing interest. Consequently, we used a mouse with a genetic deletion of Stat3 restricted to the endothelium to examine the role of STAT3 signaling in the pathophysiology of ischemic AKI. In a mouse model of ischemic AKI, the loss of endothelial STAT3 signaling significantly exacerbated kidney dysfunction, morphologic injury, and proximal tubular oxidative stress. The increased severity of ischemic AKI was associated with more robust endothelial-leukocyte adhesion and increased tissue accumulation of F4/80+ macrophages. Moreover, important proximal tubular adaptive mechanisms to injury were diminished in association with decreased tissue mRNA levels of the epithelial cell survival cytokine IL-22. In aggregate, these findings suggest that the endothelial STAT3 signaling plays an important role in limiting kidney dysfunction in ischemic AKI and that selective pharmacologic activation of endothelial STAT3 signaling could serve as a potential therapeutic target.

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