E. Schrumpf

Enzyme Activities in the Duodenal Mucosa in Duodenal Ulcer Patients

The mucosal enzyme activities of 11 marker enzymes from the brush border, basolateral membrane, and lysosomes of 45 patients with an active duodenal ulcer (DU) were determined by analysis of homogenized biopsy specimens obtained from the duodenal bulb and descending duodenum at endoscopy. They were compared with activities measured in 22 controls. In the duodenal bulb lactase (p less than 0.005), neutral-alpha-glucosidase (p less than 0.0005), and monoamine oxidase (p less than 0.0005) were significantly decreased in DU patients. In the descending duodenum all the brush border enzymes except sucrase were significantly decreased when compared with controls. DU patients with inflammation in the biopsy specimens from the duodenal bulb had decreased levels of lactase (p less than 0.05), sucrase (p less than 0.05), neutral-alpha-glucosidase (p less than 0.05), leucyl-beta-naphthylamidase (p less than 0.05), and acid phosphatases (p less than 0.05) when compared with DU patients with normal histology in this region. In the descending duodenum the activities of leucyl-beta-naphthylamidase (p less than 0.05) were decreased in patients with inflammation compared with those without such histologic changes. DU patients who had taken antacids before the investigation had decreased activities of lactase (p less than 0.05) in the descending duodenum when compared with those who had not taken antacids. Activities of lactase (p less than 0.005), sucrase (p less than 0.005), neutral-alpha-glucosidase (p less than 0.05), and acid beta-glucuronidase (p less than 0.0005) in the descending duodenum were significantly lower in smokers than in non-smokers with active DU.

Effects of Omeprazole and Eradication of Helicobacter pylori on Gastric and Duodenal Mucosal Enzyme Activities and DNA in Duodenal Ulcer Patients

BACKGROUND Duodenal and gastric content of mucosal enzymes in duodenal ulcer (DU) patients differs from that of controls. The purpose of this study has been to examine the effect of omeprazole and eradication of Helicobacter pylori on mucosal enzymes in DU patients. METHODS The enzyme activities of seven gastric and duodenal mucosal marker enzymes from the brush border, lysosomes, and mitochondria have been studied. In study I the measurements were made in 29 patients with an active DU before and after 14 days of omeprazole treatment. In study II 22 duodenal ulcer patients were given bismuth subnitrate, oxytetracycline, and metronidazole (triple therapy) for 2 weeks to eradicate H. pylori. Biopsy specimens were taken from the duodenum and the stomach for enzyme measurements and histologic assessment. In study II additional specimens were obtained from the prepyloric region for urease tests and culture of H. pylori. RESULTS The ulcer healing rates were more than 90% after both omeprazole and triple therapy. H. pylori was eradicated in 86% after triple therapy. The activities of the brush-border enzymes lactase, neutral-alpha-glucosidase, alkaline phosphatase, leucyl-beta-naphthylamidase, and gamma-glutamyltransferase (gamma-GT) increased significantly in the duodenal bulb and the descending duodenum during treatment with omeprazole. No changes in duodenal enzyme activity were detected after triple therapy, whereas a significant fall in gamma-GT and acid phosphatase activities was seen in the stomach. The mucosal DNA in the gastric antrum decreased both after treatment with omeprazole and after triple therapy. CONCLUSIONS A similar decrease in mucosal DNA of the gastric antrum was demonstrated after both omeprazole and triple therapy with bismuth subnitrate, oxytetracycline, and metronidazole. Omeprazole also affects the content of duodenal mucosal enzymes, whereas triple therapy particularly affects the gastric mucosal enzyme activity.

Flow Cytometric DNA Studies in Human Gastric Cancer and Polyps

Flow cytometric DNA studies were performed on cell suspensions of biopsy specimens from gastric tumors and neutral gastric mucosa in 18 patients with gastric cancer and 9 patients with gastric polyps. In cancer, aneuploidy was found in two tumors in the antral and five in the body part of the stomach (39%). The mean DNA index for aneuploid cancers was 1.57. In patients with aneuploid carcinomas three biopsy specimens from uninvolved mucosa also showed aneuploidy. In diploid carcinomas in the antral part of the stomach, the proliferative index (PI) was increased when compared with that of antral mucosa in controls (p less than 0.05). Increased PI was found in uninvolved mucosa in aneuploid carcinomas of the body part of the stomach when compared with that in diploid carcinomas (p less than 0.001). In uninvolved body mucosa in aneuploid carcinomas of the body part significantly reduced levels of acid-beta-glucuronidase (p less than 0.0001) were found when compared with diploid carcinomas. No polyps showed aneuploidy, and the PI in biopsy specimens from patients with gastric polyps did not differ from that in controls.

Enzyme Activities in the Gastric Mucosa in Duodenal Ulcer Patients

In a series of 45 consecutive duodenal ulcer patients (DU) the activities of 10 marker enzymes from the brush border, basolateral membrane, mitochondria, and lysosomes were determined by analysis of homogenized material taken with biopsy forceps through an endoscope from the antral and body part of the stomach. They were compared with the enzyme activities determined in controls with similar types of gastritis but without any evidence of peptic ulcer disease. All the DU patients had gastritis in the antral mucosa. In the body part, about 30% had gastritis. In the antral mucosa of DU patients the activities of the membrane and lysosomal enzymes were mostly increased when compared with the controls. In the gastric body mucosa of DU patients the activities of the lysosomal enzymes were mostly increased, whereas most of the membrane enzymes showed unchanged activities when compared with the corresponding controls. Monoamine oxidase activities were decreased or unaltered in both regions in these patients. The finding of enzymatic changes in the gastric mucosa of DU patients gives further support to an altered mucosal metabolism in these patients.

Enzyme Activities in Human Gastric Cancer and Polyps

Enzyme activities and the protein to DNA ratio in gastric biopsy specimens from patients with gastric cancer and polyps have been measured and compared with values from controls. In uninvolved mucosa in antral gastric cancer increased activities were found for several membrane and lysosomal enzymes, whereas the monoamine oxidase (MAO) activity was decreased (p less than 0.0005). In cancer tissue the MAO was also decreased (p less than 0.0003). In uninvolved mucosa in gastric cancer of the body, most membrane and lysosomal enzyme activities were increased. In the cancer tissue itself an increase in membrane enzyme activities was found for several enzymes, whereas the MAO activity was decreased (p less than 0.0001). Differences between activities in specimens from the gastric mucosa in patients with gastric polyps and those in controls were less pronounced than between gastric cancer and controls. A discriminant analysis, using the enzymes most sensitive to establish correct diagnosis, could identify normal gastric mucosa in 85-95%, atrophic gastritis in 56-63%, and uninvolved mucosa in gastric cancer in 66-78%.

Effect of Ranitidine on Gastric and Duodenal Mucosal Enzyme Activities in Duodenal Ulcer Patients

The activities of 11 marker enzymes from the gastric and duodenal mucosa were determined in 19 patients with active duodenal ulcer disease (DU) before therapy, after 4 weeks of therapy with ranitidine, 300 mg/day, and after another 4 weeks without treatment. The activities were measured in homogenized material obtained with forceps through an endoscope. The healing rate at 4 weeks was 68%. In the descending duodenum the activities of the membrane enzymes increased during the treatment period compared with pre-treatment activities. Although not as extensive as in the descending duodenum, an increase of membrane enzyme activities was also noted in the duodenal bulb during treatment. In the gastric mucosa only minor enzymic activity changes were seen. The altered enzyme activities in duodenum and stomach during treatment were independent of ulcer healing, smoking, antacids, and mucosal inflammation. Previously, significant differences in mucosal enzyme activities have been demonstrated between DU patients and controls. During ranitidine treatment the enzyme activities in the duodenal mucosa of the same DU patients tended to normalize, whereas they were mostly unchanged in the gastric mucosa. Four weeks after treatment the mucosal enzyme activities in the duodenum were as before treatment started, without occurrence of ulcer relapse. The altered enzymic activities of the duodenal mucosa in DU patients therefore seem to be largely independent of the presence of active ulcer.