Objective Patients with non-erosive reflux disease (NERD) exhibit impaired esophageal mucosal integrity, which may underlie reflux perception. In vitro topical application of an alginate solution can protect mucosal biopsies against acid-induced changes in transepithelial electrical resistance (TER). We aimed to confirm this finding in a second model using 3D cell cultures, and to assess prolonged protection in a biopsy model. Design 3D cell cultures were grown using an air liquid interface, and studied in Ussing chambers. The apical surface was "protected" with 200 µl of either alginate, viscous control, or was unprotected. The tissue was exposed to pH 3 + bile acid solution for 30 minutes and TER change was calculated. Distal esophageal mucosal biopsies were taken from 12 patients and studied in Ussing chambers. The biopsies were coated with either alginate or viscous control solution. The biopsies were then bathed in pH 7.4 solution for 1 hour. The luminal chamber solution was replaced with pH2 solution for 30 min. Percentage changes in TER were recorded. Results In the cell culture model, alginate solution protected tissue against acid-induced change in TER. In biopsies, 60 minutes after protection with alginate solution, the acidic exposure caused a -8.3 ± 2.2% change in TER compared to -25.1 ± 4.5% change after protection with the viscous control (p<0.05). Conclusions In vitro, alginate solutions can adhere to the esophageal mucosa for up to 1 hour and exert a topical protectant effect. Durable topical protectants can be further explored as add-on therapies for GERD.
- Gastroesophageal reflux disease
- Mucosal integrity
- Copyright © 2014, American Journal of Physiology- Gastrointestinal and Liver Physiology