Effect of alcohol on the integrity of the intestinal epithelium.

Abstract

SUMMARY The absorption of macromolecules from the small intestine of rats was studied in terms of the amount of peroxidase activity that appeared in thoracic duct lymph after a 10 mg dose of horseradish peroxidase had been injected directly into the lumen of the duodenum. When the horseradish peroxidase was injected as a solution in saline no peroxidase activity was detected in the lymph. When ethyl alcohol was included in the dose at final concentrations of 12.5-16% the flow rate of the lymph increased markedly for an hour or so and during this time peroxidase activity was detected in the lymph. An electronmicroscope study of the duodenal epithelium that had been exposed to alcoholic solutions of horseradish peroxidase showed that the enzyme had penetrated between the enterocytes. It was concluded that the presence in the intestine of substantial amounts of alcohol temporarily destabilises the intercellular junctions of the epithelium and thus promotes the absorption of materials which are normally excluded.Absorption from the healthy adult gastrointestinal tract of immunologically significant amounts of macromolecular material is well documented and has been reviewed.' Recent investigations of this phenomenon have used the administration of test antigens by gavage to experimental mice2 or by normal ingestion in human volunteers.3 In such situations it is not clear at which point in the gastrointestinal tract that the absorption occurs, and the role of minor traumatic lesions in the gums, oesophagus, or stomach cannot be excluded totally. In order to lessen these problems we decided to measure the absorption of antigen in rats in terms of its appearance in thoracic duct lymph, which comes principally from the small intestine and which is an obligatory pathway for any macromolecular material which has traversed intestinal wall.5 In spite of recent claims for substantial uptakes of protein antigens by tile gut of rats6 we were unable to detect in our preliminary experiments any absorption of horseradish peroxidase after a 10 mg dose of the purified enzyme had been instilled into the lumen of the duodenum. We observed, ' On sabbatical leave from the

Prevention of Alterations in Intestinal Permeability Is Involved in Zinc Inhibition of Acute Ethanol-Induced Liver Damage in Mice

“…Second, determination of intestinal permeability in various ethanol studies ex vivo and in vivo has involved the use of macromolecules, such as horseradish peroxidase, lactulose, mannitol, or 51 Chromium-EDTA (Draper et al, 1983;Bjarnason et al, 1984;Keshavarzian et al, 1994Keshavarzian et al, , 2001. In this study, we employed intragastric administration of exogenous LPS for determination of intestinal permeability because increased permeability to molecular probes, such as horseradish peroxidase, EDTA, or sugars in the small intestine is not entirely indicative of increased permeability to endotoxins.…”

Levels of histamine and other biogenic amines in high-quality red wines

“…Although red wines contain still moderate amine levels in comparison to cheese (up to 2500 mg/kg), salami (up to 600 mg/kg) and fish products (up to 4000 mg/kg) (Diel 1997), red wine intolerance might be a typical marker symptom and thus has been proposed as a model for histamine intolerance (Wantke 1994;Wantke 1999). Possibly, the pharmacologic properties of biogenic amines in wine are potentiated by some bystander effects of ethanol such as augmented gut permeability or potential interference with amine-metabolising pathways (Draper 1983;Sessa 1984).…”

Effect of Ethanol on Opioid Drug Permeability Through Caco-2 Cell Monolayers

“…Acute and chronic ethanol exposure cause functional and morphological damage to the gastrointestinal mucosal surface through mucosal injury, epithelial membrane integrity, and disruption of the tight junction barrier (6)(7)(8). Co-ingestion of alcoholic beverages with certain extended-release drug product formulations may accelerate drug release and affect the rate of its gastrointestinal absorption (9).…”