The protective effect of ischemic preconditioning associated with altered gene expression profiles in intestinal...

Ischemia-reperfusion injury after small bowel transplantation (SBT) has been considered as a trigger for early graft rejection. Ischemic preconditioning (IPC) may improve the tolerance of the small intestine to ischemic insults; however, the mechanism of IPC is still not completely elucidated. Accordingly, the aim of the present research is to investigate the molecular mechanism of IPC through a large-scale expression measurement of intragraft gene profiles by complementary DNA microarrays in SBT.

Three groups of rats were studied: S group (sham group), SBT group, and ISBT group (IPC plus SBT), in which IPC was carried out before the graft was harvested. Samples were collected from the different groups 1 h after reperfusion. Gene expression profiles of intestinal graft from the SBT group or ISBT group relative to gene expression profiles of normal intestine from the S group were analyzed respectively using 4096 gene chips.

Microarray analysis showed that 14 genes were up-regulated more than 2-fold after reperfusion compared with normal intestine, and 17 genes were down-regulated in the SBT group. In the ISBT group, 84 genes with differential expression were detected after reperfusion compared with normal intestine. It was found that 16 genes had differential expression in both the SBT and ISBT groups. These differentially expressed genes were primarily associated with cellular adhesion, energetic and substrate metabolism, and intracellular signal transduction. In addition, a number of novel genes were found.

The protective effect of IPC was correlated with regulation of cellular adhesion, improvement on energetic and substrate metabolism, and activation of intracellular signal transduction.