Caspase activation during spontaneous and radiation‐induced apoptosis in the murine intestine

Abstract

The aim of this study was to characterize the activation of caspase-3 along the crypt/villus axis in the normal and irradiated intestine and to compare active caspase-3 expression with existing apoptosis detection techniques. Small and large intestine were removed from mice at various time points after exposure to 8 Gy gamma-radiation. Positive apoptotic cells stained with an antibody against active caspase-3, haematoxylin and eosin (H&E) or TUNEL were scored in histological sections of small and large intestinal crypts and villi. In the control intestine, active caspase-3 expression was rarely observed; however, expression was markedly increased following exposure to radiation and was predominantly confined to apoptotic bodies. Measurement of apoptosis in intestinal crypts using active caspase-3 expression gave similar results to apoptosis detected from H&E-stained sections. In the normal villus, active caspase-3 expression was observed infrequently and did not significantly increase following radiation, consistent with a lack of apoptotic body formation from H&E sections. This study indicates that caspase-3 is activated in intestinal crypts but not in villi following gamma-radiation. Active caspase-3 detection compared favourably with existing immunological techniques, suggesting that it is a suitable alternative method for apoptosis quantification.

Brca2 deficiency in the murine small intestine sensitizes to p53-dependent apoptosis and leads to the spontaneous deletion of stem cells

“…As shown in Figure 2a, mice deficient in Brca2 had a significant increase in the number of histologically identified apoptotic bodies (P ¼ 0.004, n ¼ 6; all statistics were performed using a nonparametric Mann-Whitney test with a confidence level of 95%). We also scored apoptosis by counting the number of cells staining positively for the activated form of caspase 3 (Marshman et al, 2001). The same increase was observed (see Figure 2b; P ¼ 0.04, n ¼ 3), although the level of caspase 3 positivity was higher than that scored by the histological method.…”

Heat shock protein 70 is upregulated in the intestine of intrauterine growth retardation piglets

“…Interestingly, these factors may be involved in apoptosis cascade and therefore affect the homeostasis of intestinal epithelia (Baserga et al 2004;Jones and Gores, 1997). The apoptosis rate of intestinal epithelia inversely correlates with villus height and crypt depth and is accelerated by oxidative stress (Marshman et al 2001). Many studies have shown that the expression of Hsp70 was induced to prevent apoptosis and necrosis by gastrointestinal lesion of stress (Oyake et al 2006;Wada et al 2006).…”

Increased apoptosis and accelerated epithelial migration following inhibition of hedgehog signaling in adaptive small bowel postresection

“…Identification and quantification of apoptotic bodies were performed using two techniques including staining for activated caspase 3 (Cell Signaling Technology, Beverly, MA) and routine morphological assessment following hematoxylin and eosin staining of sections. Morphological changes included the presence of nuclear condensation, perinuclear clearing, and cell shrinkage (19,37). The apoptotic index was calculated as the numbers of apoptotic bodies per 100 crypt cells.…”