Dataset Information

Differential Relevance of NF-?B and JNK in the Pathophysiology of Hemorrhage/Resususcitation-Induced Liver Injury after Chronic Ethanol Feeding.

ABSTRACT:

Background

Chronic ethanol (EtOH) abuse worsens pathophysiological derangements after hemorrhagic shock and resuscitation (H/R) that induce hepatic injury and strong inflammatory changes via JNK and NF-?B activation. Inhibiting JNK with a cell-penetrating, protease-resistant peptide D-JNKI-1 after H/R in mice with healthy livers ameliorated these effects. Here, we studied if JNK inhibition by D-JNKI-1 in chronically EtOH-fed mice after hemorrhagic shock prior to the onset of resuscitation also confers protection.

Methods

Male mice were fed a Lieber-DeCarli diet containing EtOH or an isocaloric control (ctrl) diet for 4 weeks. Animals were hemorrhaged for 90 min (32 ± 2 mm Hg) and randomly received either D-JNKI-1 (11 mg/kg, intraperitoneally, i. p.) or sterile saline as vehicle (veh) immediately before the onset of resuscitation. Sham animals underwent surgical procedures without H/R and were either D-JNKI-1 or veh treated. Two hours after resuscitation, blood samples and liver tissue were harvested.

Results

H/R induced hepatic injury with increased systemic interleukin (IL)-6 levels, and enhanced local gene expression of NF-?B-controlled genes such as intercellular adhesion molecule (ICAM)-1 and matrix metallopeptidase (MMP)9. c-Jun and NF-?B phosphorylation were increased after H/R. These effects were further increased in EtOH-fed mice after H/R. D-JNKI-1 application inhibited the proinflammatory changes and reduced significantly hepatic injury after H/R in ctrl-fed mice. Moreover, D-JNKI-1 reduces in ctrl-fed mice the H/R-induced c-Jun and NF-?B phosphorylation. However, in chronically EtOH-fed mice, JNK inhibition did not prevent the H/R-induced hepatic damage and proinflammatory changes nor c-Jun and NF-?B phosphorylation after H/R.

Conclusions

These results indicate, that JNK inhibition is protective only in not pre-harmed liver after H/R. In contrast, the pronounced H/R-induced liver damage in mice being chronically fed with ethanol cannot be prevented by JNK inhibition after H/R and seems to be under the control of NF-?B.

SUBMITTER: Relja B

PROVIDER: S-EPMC4569329 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Differential Relevance of NF-κB and JNK in the Pathophysiology of Hemorrhage/Resususcitation-Induced Liver Injury after Chronic Ethanol Feeding.

Relja Borna B Weber Roxane R Maraslioglu Miriam M Wagner Nils N Borsello Tiziana T Jobin Christian C Marzi Ingo I Lehnert Mark M

PloS one 20150914 9

<h4>Background</h4>Chronic ethanol (EtOH) abuse worsens pathophysiological derangements after hemorrhagic shock and resuscitation (H/R) that induce hepatic injury and strong inflammatory changes via JNK and NF-κB activation. Inhibiting JNK with a cell-penetrating, protease-resistant peptide D-JNKI-1 after H/R in mice with healthy livers ameliorated these effects. Here, we studied if JNK inhibition by D-JNKI-1 in chronically EtOH-fed mice after hemorrhagic shock prior to the onset of resuscitatio ...[more]

PMID: 26367181

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