Remnant Intestinal Length Defines Intestinal Adaptation and Hepatic Steatosis: Two Zebrafish Models

Background Short bowel syndrome (SBS) is a condition that results from inadequate intestinal absorptive capacity, usually after the loss of functional intestine. We have previously developed a severe model of SBS in zebrafish that demonstrated increased intestinal adaptation (IA) and epithelial proliferation in SBS zebrafish. However, many children with SBS do not have this extreme intestinal loss. Therefore, in this study, we developed a variation of this model to evaluate the effects of increasing intestinal length on IA and the complications of SBS. Materials and methods After Institutional Animal Care and Use Committee approval, adult male zebrafish were assigned to three groups: sham (n = 30), S1-SBS (n = 30), and S3-SBS (n = 30). Sham surgery included ventral laparotomy alone. S1-SBS surgery consisted of laparotomy with creation of a proximal stoma at S1 (jejunostomy equivalent) and ligation at S4. S3-SBS surgery had stoma creation at S3 (ileostomy equivalent) and the same ligation. Fish were harvested at 14 d. Markers of IA were measured from proximal intestinal segments, and the liver was analyzed for development of hepatic steatosis. Results At 14 d, S3-SBS fish lost less weight than S1-SBS and had increased markers of IA compared with sham fish, which were decreased compared with S1-SBS fish. S3-SBS fish had decreased proximal intestinal inflammation compared with S1-SBS fish. S1-SBS fish developed extensive hepatic steatosis. Although S3-SBS fish have increased hepatic steatosis compared with sham fish, it is decreased compared with S1-SBS. Conclusions Longer remnant intestine decreases the extent of IA, inflammation, and hepatic steatosis in a zebrafish model of SBS.