Low-fat diet impairs postresection intestinal adaptation in a rat model of short bowel syndrome

Background: Low-fat diets (LFD) are utilized frequently in patients with short bowel syndrome (SBS). The purpose of this study was to investigate the effects of LFD on intestinal adaptation, enterocyte proliferation, and enterocyte cell death in a rat model of SBS. Methods: Adult male Sprague-Dawley rats were divided into 3 experimental groups: Sham-NC rats underwent bowel transection and reanastomosis and were fed normal chow (NC), SBS-NC rats underwent 75% small bowel resection and were fed NC, and SBS-rats were fed a low-fat diet (SBS-LFD). Parameters of intestinal adaptation, enterocyte proliferation, and enterocyte apoptosis were determined on day 14 after operation. Results: SBS-NC rats showed a significant increase (v Sham-NC) in jejunal and ileal bowel and mucosal weight, mucosal DNA and protein, villus height, and crypt depth. A significant 67% increase in crypt cell proliferation rate and 265% increase in villus enterocyte apoptosis was seen in the ileum of SBS-NC rats compared with control animals (P < .05). SBS-LFD animals showed lower ileal mucosal weight (29%; P < .05), jejunal crypt depth (20%; P < .05), and ileal villus height (21%; P < .05). A significant decrease in villus apoptosis in jejunum (74%; P < .05) and ileum (67%; P < .05) and a decrease in cell proliferation in ileum (35%; P < .05) was seen also after exposure to LFD compared with SBS-NC. Conclusions: In a rat model of SBS, early LFD appears to inhibit parameters of intestinal adaptation. A possible mechanisms for this effect may be decreased cell proliferation. Decreased enterocyte loss via apoptosis, found in this study, may reflect a reduced number of enterocyte.