Activation of PI3-kinase/Akt induced small bowel cell apoptosis during laparoscopic ischaemia-reperfusion of swine jejunum.

Abstract

INTRODUCTION: This study aimed to detect small bowel cell apoptosis by evaluating the nuclear activation of transcription factors, nuclear factor-kappaB (NF-kappaB) and Akt pathways as well as detecting apoptotic cells by TUNEL assay, during ischaemia-reperfusion (I/R) injury by Arterio-Venous Occlusion (AVO) of ajejunal loop in swine, using a laparoscopic procedure. MATERIALS AND METHODS: A jejunal loop was isolated and a biopsy sample (T0) obtained. Biopsies were obtained at 30 minutes (T30I) and 60 minutes (T60I) after clamping and again during reperfusion (R), T30R and T60R. Standard H&E stains and immunohistochemical study for infiltrating polymorphonuclear leukocytes and TUNEL assays were performed. The activation of Akt and NF-kappaB in the animal model was evaluated by indirect immunofluorescence and confocal microscopy. CONCLUSIONS: Our results confirmed that I/R injury of the jejunum did not only cause epithelial damage, but also activated the molecular pathways triggering an apoptotic reaction (by pro-inflammatory cytokines) and an anti-apoptotic mechanism that can lead to the regeneration of injured tissue.