Background: Sulfhydryl (SH) compounds are essential in maintaining mucosal integrity in the gastrointestinal tract. A decrease in colonic mucosal SH compounds affects the redox status of the mucosa, resulting in vulnerability to further attacks. Therefore, there is a strong need for in vivo evaluation of SH compounds in the colonic mucosa. Aims: The aim of the current study was to establish a m...

In patients with ulcerative colitis (UC) the cumulative risk of colon cancer is lower than the actual rate of dysplasia suggesting an efficient immune surveillance mechanism. Since the co-stimulatory molecule CD80 is overexpressed in dysplastic colonic mucosa of UC patients and T-cell activation entails effective costimulation, we aimed to evaluate the functional implication of CD80 signaling i...

A primary metabolic disorder may be present in the colonic mucosa of patients with ulcerative colitis. Preserving the epithelium in situ, we evaluated the metabolism of the colonic mucosa of control patients and patients with ulcerative colitis and Crohn's disease. Colonic mucosal strips (approximately 500 mg) were incubated with partially 14C-labeled acetate (C2), butyrate (C4), hexanoate (C6)...

Recent studies have suggested that nitric oxide (NO.), the product of nitric oxide synthase in inflammatory cells, may play a part in tissue injury and inflammation through its oxidative metabolism. In this study the colonic generation of oxides of nitrogen (NOx) and nitric oxide synthase activity was determined in ulcerative colitis and Crohn's disease. Colonic biopsy specimens were obtained f...

Serum anticolon antibody and in vitro anti-colon antibody production by peripheral blood and mucosal lymphocytes was investigated in patients with ulcerative colitis. The frequency of serum anticolon antibody was 71% in 41 patients with ulcerative colitis, estimated by enzyme linked immunosorbent assay (ELISA) using isolated rat colon epithelial cells. This finding confirms our previous report ...

Long-term exposure of colonic mucosa to urinary content and its association with increased risk of infection, mechanical and biochemical irritation, and malignancy have been described in the literature. Existing case reports and studies depict the low but distinct risk of malignancy in gastrointestinal segments which come in contact with urinary content as a result of surgical correction of uri...

We aimed to investigate the effects of brain-derived neurotrophic factor (BDNF) on apoptosis of intestinal epithelial cells (IECs) and alterations of intestinal barrier integrity using BDNF knock-out mice model. Colonic tissues from BDNF(+/+) mice and BDNF(+/-) mice were prepared for this study. The integrity of colonic mucosa was evaluated by measuring trans-mucosa electrical resistance and ti...

Protein kinase C (PK-C) seems to be involved in the regulation of growth and differentiation of normal epithelial cells. Colonic adenomas and carcinomas show increased proliferation and decreased differentiation. We investigated the activity and subcellular distribution of PK-C in biopsies of normal, neoplastic, and malignant colonic epithelium to evaluate alterations in enzyme activity. In the...

BACKGROUND/AIMS Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, which catalyzes the formation of reactive oxygen species (ROS) in phagocytic cells, has five subunits: p67phox ("phox"refers to "phagocyte oxidase"), p47phox, p40phox, p22phox, and gp91phox (catalytic subunit). Oxidative stress resulting from the accumulation of ROS and/or defective removal of ROS by antioxidants has d...

AIM To measure the intracolonic release of nitric oxide end products (nitrates plus nitrites) and eicosanoids in response to intraluminal irritation with deoxycholic acid (DCA). PATIENTS Seven patients with irritable bowel syndrome. METHODS The left colon was perfused with a solution with or without 3 mM deoxycholic acid. Aspirates were assayed for eicosanoids by specific radioimmuno-assay,...