Apical effect of diosmectite on damage to the intestinal barrier induced by basal tumour necrosis factor-alpha.

BACKGROUND: In many digestive diseases the intestinal barrier is weakened by the release of proinflammatory cytokines, including tumour necrosis factor-alpha (TNF alpha). AIM: To investigate the protective effect of apical diosmectite on the intestinal dysfunction induced by the proinflammatory cytokine TNF alpha. METHODS: Filter grown monolayers of the intestinal cell line HT29-19A were incubated for 48 hours in basal medium containing 10 ng/ml TNF alpha and 5 U/ml interferon-gamma (IFN gamma). Next, 1, 10, or 100 mg/ml diosmectite was placed in the apical medium for one hour. Intestinal function was then assessed in Ussing chambers by measuring ionic conductance (G) and apicobasal fluxes of 14C-mannitol (Jman), and intact horseradish peroxidase. In control intestinal monolayers, diosmectite did not significantly modify G, Jman, or intact horseradish peroxidase. RESULTS: After incubation with TNF alpha and IFN gamma, intestinal function altered, as shown by the increases compared with control values for G (22.8 (3.7) v (9.6 (0.5) mS/cm2), Jman (33.8 (7.5) v 7.56 (0.67) micrograms/h x cm2), and intact horseradish peroxidase (1.95 (1.12) v 0.14 (0.04) micrograms/h x cm2). G and Jman were closely correlated, suggesting that the increase in permeability was paracellular. Treatment with diosmectite restored al the variables to control values. CONCLUSIONS: Basal TNF alpha disrupts the intestinal barrier through the tight junctions, and apical diosmectite counteracts this disruption.

Protective action of diosmectite treatment on digestive disturbances induced by intestinal anaphylaxis in the guinea-pig.

METHODS: Colonic transit time, faecal moisture and intestinal permeability were assessed in guinea-pigs sensitized intraperitoneally with cow's milk and challenged with an oral administration of beta-lactoglobulin. One group of animals was treated for 1 week with diosmectite (500 mg.kg/day) and another with placebo. A control group was not sensitized but treated with diosmectite. RESULTS: In sensitized animals receiving placebo, challenge with beta-lactoglobulin induced a significant (P < 0.05) decrease in colonic transit time, and increases in faecal moisture and intestinal permeability. These changes were not observed in animals treated with diosmectite. CONCLUSION: Diosmectite pre-treatment protects against allergic digestive disturbances induced by antigen administration in guinea-pigs sensitized to cow's milk.

[Digestive disorders and self medication observed during a competition in endurance athletes. Prospective epidemiological study during a championship of triathlon]. / Troubles digestifs et automédication constatés en compétition chez les sportifs d'endurance. Enquête epidémiologique prospective sur une saison sportive de triathlon.

Gastro-intestinal disorders were described during long lasting exercise. However, no systematic evaluation was done before the study of the French Medical Society of Triathlon, which realized an epidemiologic analysis during the French triathlon championship in 1989. The aims of this study were to evaluate the prevalence and the nature of different gastro-intestinal symptoms, to precise the severity and the consequences of these disorders, and to evaluate the self-medication. This study concern 25,640 competitors of the 101 meetings of the French triathlon championship 1989 (75 category A, 19 category B and 7 category C). Two thousand two hundred and seventy four competitors had gastric symptoms like nausea, epigastgric pain or vomiting (8.9%); 2,046 competitors had intestinal troubles like diarrhea or abdominal pain (8%). These results confirm the suffering of the gastro-intestinal tract during a long lasting exercise like a triathlon. These disorders are well known, so self-medication was used for gastric symptoms (0.7%) or intestinal disturbances (18.2%).

Effect of diosmectite on intestinal permeability changes in acute diarrhea: a double-blind placebo-controlled trial.

The effect of diosmectite on intestinal permeability changes in acute diarrhea was measured during a double-blind placebo-controlled trial carried out in 59 Gabonese children aged 5-35 months. Intestinal permeability tests (IPTs), measuring the urinary elimination of orally administered lactulose and mannitol at a dosage of 1 g/10 kg each, were performed during the morning following admission and repeated 2 days later after treatment by diosmectite or placebo. During the first IPT, urine volume and lactulose and mannitol urinary recoveries were comparable in the diosmectite and in the placebo groups: 50 vs. 35.5 ml (median; p = 0.21), 1.01 vs. 1.27% (p = 0.35), and 2.20 vs. 2.87% (p = 0.12). As a result, the lactulose/mannitol (L/M) ratio was similar in the two groups: 44.44 vs. 35.33% (p = 0.98). During the second IPT, the urinary lactulose recovery decreased similarly in both groups (-0.18 vs. -0.29%; p = 0.76), whereas the urinary mannitol recovery exhibited opposite variations, the increase in the diosmectite group (+ 1.43%) contrasting significantly with the decrease in the placebo group (-0.47%; p = 0.01). When comparing the first and the second IPT, the decrease of the L/M ratio was significant in the diosmectite group (44.44 vs. 28.32%; p = 0.02) and not in the placebo group (35.33 vs. 48.23%; p = 0.91). During gastroenteritis, diosmectite appears to enhance absorption of mannitol, a marker of intestinal absorptive area.