Intestinal enzymes during malnutrition & infection in rabbits.

BACKGROUND & OBJECTIVES: Malnutrition plays an important role in the intestinal absorption of nutrients. However, reports are not consistent whether intestinal enzymes are decreased in the presence of malnutrition. It is also not clear whether simultaneous presence of malnutrition and infection adds to the problem of malabsorption of nutrients. The aim of the present study was to determine intestinal functions in terms of concentrations of disaccharidase enzymes during diarrhoea and protein energy malnutrition. METHODS: Concentrations of three disaccharidase enzymes, namely maltase, sucrase and lactase were measured in nine energy-restricted and five control rabbits during diarrhoea induced by rabbit diarrhoeagenic Escherichia coli (RDEC-1). Malnutrition was achieved in the rabbit model by feeding the animals for 30 days with half the amount of food fed to well-nourished control rabbits. Both the energy-restricted and the control groups were challenged by RDEC-1. Diarrhoea occurred on day 1-7 after administration of the strain. After onset of diarrhoea, both groups of rabbits were sacrificed and their intestinal mucosa was examined to determine the concentration of lactase, maltase and sucrase. RESULTS: The energy-restricted animals and controls did not differ significantly for concentrations (units/mg proteins) of lactase (0.65 +/- 0.28 vs 0.56 +/- 0.17 ), maltase (6.20 +/- 2.70 vs 6.47 +/- 1.90) and sucrase (5.42 +/- 2.30 vs 5.13 +/- 1.40) measured during acute infectious diarrhoea. INTERPRETATION & CONCLUSION: The results suggested that the enzymatic functions of the intestinal brush border were not statistically different during diarrhoea among malnourished rabbits compared with their well-nourished counterparts.

Pattern of disaccharidases in chronic diarrhoea and malabsorption

Disaccharide-splitting enzymes were analyzed in the jejunal mucosae of 48 patients suffering from chronic diarrhoea and/or malabsorption, and the results were compared to those of 11 controls. Four [36.4%] of the controls were found to have partial lactase deficiency with a mean ratio of sucrase to lactase activity of 54.8 [SEM +/- 60.06] Significant reduction in the disaccharidases [lactase, sucrase, maltase, and isomaltase] were observed in patients with celiac disease and primary intestinal lymphoma; other groups exhibited variable affection in all disaccharidasas. High incidence of hypolactasia in these patients is the net results of both genetic influence on lactase activity and as a consequence to mucosal injury. It is suggested that further studies should be carried out using intestinal biopsy and direct enzyme assay in a large number of healthy adults

Antisecretory activity in a lectin fraction of plasma from patients with acute diarrhea

The present study describes the first attempt to detect antisecretory activity in a lectin fraction of plasma from patients with acute diarrhea. The plasma antisecretory protein (ASP) was purified by affinity chromatography in agarose, and its antisecretory activity in rats subjected to intestinal challenge with cholera toxin. During the first 24 h of the diarrheal episode, antisecretory activity in patients (median 0, range 0 -25 percent) was lower than that seen in the asymptomatic group (median 10, range 0 -30 percent); 3 days leter, when diarrhea ceased in most of the patients, the ASP activity increased significantly (median 30, range 0 -70 percent). However, 5 days later the activity decreased again (median 0, range 0 . 55 percent). No differences in ASP levels were found between cases associated with an enteropathogen and those whwew no pathogen was identified. These findings reveal an inverse relationship between the increase in ASP and the patient's intestinal secretion; suggesting that ASP plays a role in the compensatory mechanisms that occur in diarrhea in humans