Digestive enzyme expression in the large intestine of children with short bowel syndrome in a late stage of adaptation.

BACKGROUND AND AIMS: Intestinal adaptation in short bowel syndrome (SBS) includes morphologic processes and functional mechanisms. This study investigated whether digestive enzyme expression in the duodenum and colon is upregulated in SBS patients. METHOD: Sucrase-isomaltase (SI), lactase-phlorizin hydrolase (LPH), and neutral Aminopeptidase N (ApN) were analyzed in duodenal and colonic biopsies from nine SBS patients in a late stage of adaptation as well as healthy and disease controls by immunoelectron microscopy (IEM), Western blots, and enzyme activities. Furthermore, proliferation rates and intestinal microbiota were analyzed in the mucosal specimen. RESULTS: We found significantly increased amounts of SI, LPH, and ApN in colonocytes in most SBS patients with large variation and strongest effect for SI and ApN. Digestive enzyme expression was only partially elevated in duodenal enterocytes due to a low proliferation level measured by Ki-67 staining. Microbiome analysis revealed high amounts of Lactobacillus resp. low amounts of Proteobacteria in SBS patients with preservation of colon and ileocecal valve. Colonic expression was associated with a better clinical course in single cases. CONCLUSION: In SBS patients disaccharidases and peptidases can be upregulated in the colon. Stimulation of this colonic intestinalization process by drugs, nutrients, and pre- or probiotics might offer better therapeutic approaches.

Bile salt dependent lipase promotes intestinal adaptation in rats with massive small bowel resection.

Intestinal adaptation is important for the short bowel syndrome (SBS) patients. Growing evidence has suggested that bile salt dependent lipase (BSDL) not only has the lipolytic activity, but also the immune-modulating and pro-proliferative activities. The purpose of the present study was to investigate the effects of BSDL on intestinal adaptive growth and gut barrier function in a rat model of SBS. Twenty-four male Sprague-Dawley rats were randomly divided into three experimental groups: sham group (rats underwent bowel transection and re-anastomosis), SBS group (rats underwent 80% bowel resection), SBS-BSDL group (SBS rats orally administered BSDL). The animals were weighed daily. The intestinal morpho-histochemical changes and intestinal barrier function were determined 14 days after the operations. Meanwhile, the expressions of Wnt signaling molecules in enterocytes were also analyzed by immunohistochemistry and Western blot. The postoperative weight gain was faster in the SBS rats treated with BSDL than in the SBS/untreated group. The SBS rats treated with BSDL had significantly greater villus height, crypt depth, and enterocyte proliferation in their residual intestines, as compared with the SBS/untreated group. The recovery of intestinal barrier function was promoted and the expressions of tight-junction proteins were increased in the SBS rats treated with BSDL. Additionally, the data indicated that the proadaptive activities of BSDL might be mediated by Wnt signaling activation in the enterocytes. These observations suggested that enteral BSDL administration promoted intestinal adaptive growth and barrier repairing by activating Wnt signaling pathway in SBS rats.

Inhibition of ACE activity contributes to the intestinal structural compensation in a massive intestinal resection rat model.

BACKGROUND: Intestinal adaptation in short bowel syndrome (SBS) consists of increased epithelial cells (ECs) proliferation as well as apoptosis. Angiotensin-converting enzyme (ACE) has been shown to regulate ECs apoptosis. In this study, we investigated the effect of ACE inhibition on intestinal adaptation after small bowel resection (SBR) in a rat model. METHODS: Sprague-Dawley rats were used and were divided into four groups: (1) Sham group received an ileum transection (n = 6); (2) Sham + ACE-I group received an ileum transaction and lavage with ACE inhibitor (ACE-I, enalaprilat, 2 mg/kg/day) (n = 6); (3) SBS group received a 70 % mid-intestinal resection (n = 6); (4) SBS + ACE-I group received a 70 % mid-intestinal resection and lavage with enalaprilat (2 mg/kg/day) (n = 6). Sampling was done 10 days after surgery. ECs apoptosis was studied by TUNEL staining. ACE, angiotensin II (ANGII) receptor type 1 (AT1R) and receptor type 2 (AT2R) expressions were detected with RT-PCR and immunofluorescent confocal microscopy. RESULTS: SBR leads to significant intestinal hypertrophy. The addition of ACE-I to SBS rat resulted in a significant decline in ECs apoptosis. ACE mRNA expression was significantly elevated after SBS creation (0.24 ± 0.07 vs. 0.42 ± 0.11), and ACE-I administration further increased mucosal ACE mRNA expression (0.54 ± 0.12). Interestingly, AT1R mRNA expression showed a significant decline in the SBS group compared to Sham levels, and ACE-I administration increased AT1R mRNA expression to Sham levels. No significant difference in AT2R mRNA expression was found between Sham and SBS group. CONCLUSION: These results offer further insight into the role of ACE on intestinal mucosal remolding after massive bowel resection. ACE-I may be beneficial to SBS patients via a reduction of the apoptotic rate, thus facilitating the degree of adaptation.

Intestinal intraepithelial lymphocyte derived angiotensin converting enzyme modulates epithelial cell apoptosis.

BACKGROUND & AIMS: Intestinal adaptation in short bowel syndrome (SBS) consists of increased epithelial cell (EC) proliferation as well as apoptosis. Previous microarray analyses of intraepithelial lymphocytes (IEL) gene expression after SBS showed an increased expression of angiotensin converting enzyme (ACE). Because ACE has been shown to promote alveolar EC apoptosis, we examined if IEL-derived ACE plays a role in intestinal EC apoptosis. METHODS: Mice underwent either a 70% mid-intestinal resection (SBS group) or a transection (Sham group) and were studied at 7 days. ACE expression was measured, and ACE inhibition (ACE-I, enalaprilat) was used to assess ACE function. RESULTS: IEL-derived ACE was significantly elevated in SBS mice. The addition of an ACE-I to SBS mice resulted in a significant decline in EC apoptosis. To address a possible mechanism, tumor necrosis factor alpha (TNF-alpha) mRNA expression was measured. TNF-alpha was significantly increased in SBS mice, and decreased with ACE-I. Interestingly, ACE-I was not able to decrease EC apoptosis in TNF-alpha knockout mice. CONCLUSIONS: This study shows a previously undescribed expression of ACE by IEL. SBS was associated with an increase in IEL-derived ACE. ACE appears to be associated with an up-regulation of intestinal EC apoptosis. ACE-I significantly decreased EC apoptosis.

[Digestive pathology and digestive function of small intestine mucous layer]. / Pishchevaritel'naia funktsiia pristenochnogo slizistogo sloia tonkoi kishki pri patologii organov pishchevareniia.

The research of small intestine mucous layer at children and adults is carried out. It is revealed high meanings enzyme distribution in human small intestine mucous layer and their change at celiac disease, food allergy, short-bowel syndrome.

Intestinal ornithine decarboxylase in short bowel syndrome patients with oral diet.

The major consequence of extensive intestinal resection is loss of absorptive surface area, which results in malabsorption of nutrients; this condition is known as short-bowel syndrome (SBS). Patients with extensive small intestinal resection and colectomy leading to jejunostomy have the most severe SBS. Ornithine decarboxylase (ODC) plays a central role in cell proliferation and in the process of gut adaptation. Polyamine synthesis in crypt cells mediates the action of extracellular growth factors on DNA synthesis and mitotic activity. The aim of this study was to examine ODC expression and activity, diamine oxidase (DAO) activity and polyamine levels in the jejunal mucosa and red blood cells of SBS patients with a jejunostomy. The study group consisted of 6 patients (4 men and 2 women, mean age 55.8+/-9.8 years), who had undergone extensive small bowel resection and colectomy. All patients were maintained on cyclic parenteral nutrition and non-restricted oral nutrition. Two groups of patients operated on for unrelated reasons were included as the jejunum control group (n=6) and the ileum control group (n=13). Non statistical differences were observed in polyamine levels of red blood cells versus the control group (spermidine: 21.0+/-3.6 vs. 17.7+/-1.1 and spermine: 17.1+/-8.6 vs. 13.2+/-1.6 nmol/ml RBC, respectively). No significant decreases in putrescine and spermidine levels were observed between the groups, but spermine levels in SBS jejunum were significantly lower than the controls (P<0.05). In SBS patients a significant decrease in ODC and DAO activity were observed vs jejunum. A significant decrease in ODC-mRNA abundance was found for the SBS patients as compared to the two control groups (P<0.05). These results suggest that in SBS patients with jejunostomy intestinal adaptation may be impaired.

Small intestinal mucosa changes, including epithelial cell proliferative activity, of children receiving total parenteral nutrition (TPN).

We examined the small intestinal histology disaccharidase activities as well as the incorporation of [3H]thymidine into DNA of biopsies maintained in organ culture from seven children (ages 9 months to 5 years) receiving total parenteral nutrition (TPN). Three children suffered from inflammatory bowel disease and received TPN for one month (short term). Four required long-term TPN (> 9 months) for short-bowel syndrome. DNA was extracted from the samples following serial precipitation with perchloric acid. Results were compared to those from 22 age-matched children investigated for abdominal pain or chronic diarrhea. Short-term TPN resulted in slightly lower lactase, sucrase, and palatinase activities that were not statistically different from controls. Long-term TPN resulted in focal mild villus atrophy and a decrease in disaccharidase activity in two patients. Biopsies from long-term TPN patients incorporated less thymidine compared to those of controls (P < 0.001) when data was expressed per total biopsy (3.6 +/- 1.1 vs. 8.4 +/- 1.1 fmol) or per milligram of tissue (1.0 +/- 0.12 vs 2.7 +/- 0.7 fmol). The above data are in general agreement with the hypoplastic effect of TPN in animals. However, in children, much longer periods of TPN are required to realize the changes.