Induction of cell death in rat small intestine by ischemia reperfusion: differential roles of Fas/Fas ligand and Bcl-2/Bax systems depending upon cell types.
Although ischemia reperfusion (I/R) induces apoptotic damage of mammalian small intestine, the molecular mechanism is largely unknown. We investigated the appearance of apoptosis at various time-points (0-24 h) of reperfusion after 1-h ischemia and the expression of various apoptosis-related proteins, such as Bcl-2, Bax, Fas, Fas ligand (FasL), activated caspase-3, and cytochrome c, immunohistochemically in rat small intestine. As assessed by TUNEL and electron microscopy, apoptotic cells were increased at 3 h of reperfusion in all intestinal parts (villous epithelium, crypt epithelium, and stroma of intestine). Moreover, the TUNEL-positive cells in the stroma were later identified as T cells. The expression of Fas and FasL as well as activated caspase-3 was markedly increased at 3 h of reperfusion in the stroma. In the villous epithelium, a transient decrease in Bcl-2 expression was found while in the crypt epithelium, Fas expression was induced. Finally, intraperitoneal injection of leupeptin (an SH-protease inhibitor) after I/R resulted in a significant inhibition of the induction of apoptosis in the stroma and crypt epithelium. Our results indicate that the triggering molecules of apoptosis in the I/R rat small intestine may vary depending on cell type and that the use of a broad-spectrum protease inhibitor may reduce intestinal damage.
An
Shucai
S
Division of Histology and Cell Biology, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4, Sakamoto, Nagasaki 8528523, Japan.
Hishikawa
Yoshitaka
Y
Koji
Takehiko
T
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3; D061945:Caspase Inhibitors; D020169:Caspases / Q000032:analysis; D045304:Cytochromes c / Q000032:analysis; D053222:Fas Ligand Protein; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007421:Intestine, Small / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D007976:Leupeptins / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000032:analysis; D008854:Microscopy, Electron; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology*; D051028:bcl-2-Associated X Protein
C494828:Bax protein, rat; D061945:Caspase Inhibitors; D053222:Fas Ligand Protein; C505662:Faslg protein, rat; D007976:Leupeptins; D008562:Membrane Glycoproteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases; C032854:leupeptin