GI09 - Localization of Glucose Transporter 2 RNA in Small Intestine of Dogs with Chronic Inflammatory Enteropathy

Abstract: Background – Soluble carbohydrates provide nutritional value and are digested and absorbed mainly in the small intestine. Previous studies showed increased fecal concentrations of glucose and other carbohydrates in a subset of dogs with chronic inflammatory enteropathy (CIE) compared to healthy controls (HC). Therefore, malabsorption was suspected with dysregulation of the intestinal carbohydrate transporter possibly playing a role. However, the localization of carbohydrate transporters has not been described in dogs. Objective – Describe intestinal RNA localization of SLC2A2 (gene encoding the glucose transporter 2) in dogs with CIE and HC. Animals – Duodenum biopsies from 8 HC and 23 dogs with CIE; ileum biopsies from 9 HC and 19 dogs with CIE. Methods – Retrospective cross-sectional study. RNA expression of SLC2A2 in duodenum and ileum was assessed by in situ hybridization and quantified by QuPath as dots per 2.37 mm2. Results – SLC2A2 RNA expression was identified only in the duodenum of both HC and CIE dogs. The nucleus and cytoplasm of epithelial cells in villi and crypts were positive. No expression was identified in the lamina propria, submucosa, and muscularis. The RNA expression of SLC2A2 in villi and crypts did not differ between HC and CIE (Mann-Whitney U tests, P=0.34 and P=0.67, respectively). Conclusions and clinical importance – RNA expression of SLC2A2 is distributed in duodenal epithelial cells but absent in ileum of dogs. As expression did not differ between HC and dogs with CIE, the cause of increased fecal glucose concentrations in the latter remains to be determined.