Dataset Information

Inhibition of IKKβ in enterocytes exacerbates sepsis-induced intestinal injury and worsens mortality.

ABSTRACT:

Objectives

Nuclear factor-κB is a critical regulator of cell-survival genes and the host inflammatory response. The purpose of this study was to investigate the role of enterocyte-specific NF-kB in sepsis through selective ablation of IkB kinase.

Design

Prospective, randomized controlled study.

Setting

Animal laboratories in university medical centers.

Subjects and interventions

Mice lacking functional NF-kB in their intestinal epithelium (Vil-Cre/Ikkβ) and wild-type mice were subjected to sham laparotomy or cecal ligation and puncture. Animals were killed at 24 hours or followed 7 days for survival.

Measurements and main results

Septic wild-type mice had decreased villus length compared with sham mice, whereas villus atrophy was further exacerbated in septic Vil-Cre/Ikkβ mice. Sepsis induced an increase in intestinal epithelial apoptosis compared with sham mice, which was further exacerbated in Vil-Cre/Ikkβ mice. Sepsis induced intestinal hyperpermeability in wild-type mice compared with sham mice, which was further exacerbated in septic Vil-Cre/Ikkβ mice. This was associated with increased intestinal expression of claudin-2 in septic wild-type mice, which was further increased in septic Vil-Cre/Ikkβ mice. Both, pro-inflammatory and anti-inflammatory cytokines were increased in serum following cecal ligation and puncture, and interleukin 10 and monocyte chemoattractant protein-1 levels were higher in septic Vil-Cre/Ikkβ mice than in septic wild-type mice. All septic mice were bacteremic, but no differences in bacterial load were identified between wild-type and Vil-Cre/Ikkβ mice. To determine the functional significance of these results, animals were followed for survival. Septic wild-type mice had lower mortality than septic Vil-Cre/Ikkβ mice (47% vs 80%, p<0.05). Antitumor necrosis factor administration decreased intestinal apoptosis, permeability, and mortality in wild-type septic mice, and a similar improvement in intestinal integrity and survival were seen when antitumor necrosis factor was given to Vil-Cre/Ikkβ mice.

Conclusions

Enterocyte-specific NF-kB has a beneficial role in sepsis by partially preventing sepsis-induced increases in apoptosis and permeability, which are associated with worsening mortality.

SUBMITTER: Dominguez JA

PROVIDER: S-EPMC3823541 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Publications

Inhibition of IKKβ in enterocytes exacerbates sepsis-induced intestinal injury and worsens mortality.

Dominguez Jessica A JA Samocha Alexandr J AJ Liang Zhe Z Burd Eileen M EM Farris Alton B AB Coopersmith Craig M CM

Critical care medicine 20131001 10

<h4>Objectives</h4>Nuclear factor-κB is a critical regulator of cell-survival genes and the host inflammatory response. The purpose of this study was to investigate the role of enterocyte-specific NF-kB in sepsis through selective ablation of IkB kinase.<h4>Design</h4>Prospective, randomized controlled study.<h4>Setting</h4>Animal laboratories in university medical centers.<h4>Subjects and interventions</h4>Mice lacking functional NF-kB in their intestinal epithelium (Vil-Cre/Ikkβ) and wild-type ...[more]

PMID: 23939348

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Dataset Information

Inhibition of IKKβ in enterocytes exacerbates sepsis-induced intestinal injury and worsens mortality.

Objectives

Design

Setting

Subjects and interventions

Measurements and main results

Conclusions

Publications

Inhibition of IKKβ in enterocytes exacerbates sepsis-induced intestinal injury and worsens mortality.

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