Intestinal ischemic preconditioning after ischemia/reperfusion injury in rat intestine: profiling global gene expression patterns.
OBJECTIVE
Intestinal ischemia/reperfusion (IR) injury involves activation of inflammatory mediators, mucosal necrosis, ileus, and alteration in a variety of gene products. Ischemic preconditioning (IPC) reduced all the effects of intestinal injury seen in IR. In an effort to investigate the molecular mechanisms responsible for the protective effects afforded by IPC, we sought to characterize the global gene expression pattern in rats subjected to IPC in the setting of IR injury.


METHODS
Rats were randomized into five groups: (1) Sham, (2) IPC only (3) IR, (4) Early IPC + IR (IPC --> IR), and (5) Late IPC + IR (IPC --> 24 h --> IR). At 6 h after reperfusion, ileum was harvested for total RNA isolation, pooled, and analyzed on complementary DNA (cDNA) microarrays with validation using real-time polymerase chain reaction (PCR). Significance Analysis of Microarray (SAM) software was used to determine statistically significant changes in gene expression.


RESULTS
Early IPC + IR had 5,167 induced and 4 repressed genes compared with the other groups. SAM analysis revealed 474 out of 10,000 genes differentially expressed among the groups. Early and Late IPC + IR had more genes involved in redox hemostasis, the immune/inflammatory response, and apoptosis than either the IPC only or IR alone groups.


CONCLUSIONS
The transcriptional profile suggests that IPC exerts its protective effects by regulating the gene response to injury in the intestine.
Moore-Olufemi
Stacey D
SD
Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, TX 77030, USA. stacey.d.moore-olufemi@uth.tmc.edu
Olufemi
Shodimu-Emmanuel
SE
Lott
Steve
S
Sato
Norio
N
Kozar
Rosemary A
RA
Moore
Frederick A
FA
Radhakrishnan
Ravi S
RS
Shah
Shinil
S
Jimenez
Fernando
F
Kone
Bruce C
BC
Cox
Charles S
CS
D000704:Analysis of Variance; D000818:Animals; D016000:Cluster Analysis; D004195:Disease Models, Animal; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007082:Ileum / Q000098:blood supply* / Q000473:pathology; D007413:Intestinal Mucosa / Q000473:pathology; D019194:Ischemic Preconditioning / Q000379:methods*; D008297:Male; D046228:Microarray Analysis; D020411:Oligonucleotide Array Sequence Analysis; D011336:Probability; D012313:RNA / Q000235:genetics; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D015427:Reperfusion Injury / Q000235:genetics* / Q000517:prevention & control; D020133:Reverse Transcriptase Polymerase Chain Reaction
D012313:RNA