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 -