TY - JOUR
T1 - Salmonella Typhimurium infection in the porcine intestine
T2 - evidence for caspase-3-dependent and -independent programmed cell death
AU - Schauser, Kirsten
AU - Olsen, John Elmerdahl
AU - Larsson, Lars-Inge
PY - 2005
Y1 - 2005
N2 - The normal intestinal epithelium is renewed with a turnover rate of 3-5 days. During Salmonella infection increased cell loss is observed, possibly as a result of programmed cell death (PCD). We have, therefore, studied the effects of Salmonella Typhimurium infection on three elements involved in PCD: caspase-3 activation, c-Jun phosphorylation on serine 63 (both detected by immunocytochemistry), and DNA fragmentation (detected by TUNEL reaction), using a pig jejunal loop model. Additionally, we used nuclear staining for detecting signs of classical apoptosis. Activated caspase-3 was detected in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P<0.0001). An increase in phospho-c-Jun in epithelial cells was already detectable 5 min after infection and often occurred in cells that appeared not to be invaded by the organism. Changes in caspase-3 activation and c-Jun phosphorylation were most marked in the proximal region of the jejunum. Although rarely observed in the epithelium, proper TUNEL-positive cells were frequently found in the intestinal lumen. Some, but not all, TUNEL-positie cells were also positive for caspase-3, indicating that both caspase-3-dependent and -independent pathways of PCD increased upon infection.
AB - The normal intestinal epithelium is renewed with a turnover rate of 3-5 days. During Salmonella infection increased cell loss is observed, possibly as a result of programmed cell death (PCD). We have, therefore, studied the effects of Salmonella Typhimurium infection on three elements involved in PCD: caspase-3 activation, c-Jun phosphorylation on serine 63 (both detected by immunocytochemistry), and DNA fragmentation (detected by TUNEL reaction), using a pig jejunal loop model. Additionally, we used nuclear staining for detecting signs of classical apoptosis. Activated caspase-3 was detected in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P<0.0001). An increase in phospho-c-Jun in epithelial cells was already detectable 5 min after infection and often occurred in cells that appeared not to be invaded by the organism. Changes in caspase-3 activation and c-Jun phosphorylation were most marked in the proximal region of the jejunum. Although rarely observed in the epithelium, proper TUNEL-positive cells were frequently found in the intestinal lumen. Some, but not all, TUNEL-positie cells were also positive for caspase-3, indicating that both caspase-3-dependent and -independent pathways of PCD increased upon infection.
KW - Former LIFE faculty
KW - Caspase-3
KW - c-Jun
KW - Intestine
KW - Pig
KW - Programmed elle deatch
KW - Salmonella
U2 - 10.1007/s00418-004-0731-8
DO - 10.1007/s00418-004-0731-8
M3 - Journal article
C2 - 15609044
VL - 123
SP - 43
EP - 50
JO - Histochemical Cell Biology
JF - Histochemical Cell Biology
IS - 1
ER -