Effect of dietary bulk on small intestinal morphology and cell renewal in the rat

Isotonic Tube Feeding Formula Induces Liquid Stool in Normal Subjects: Reversal by Pectina

“…There was no significant difference between subjects in groups 1 and 2 during dietary period 2 for any of the variables measured. § § In dietary period 2, the mean ± SEM for caloric intake = 27.6 ± 1.4 kcal/kg/day, 28.0 ± 1.2 kcal/kg/day for groups 1 and 2, respectively; for Na+ = 9.8 ± 2.3 mEq/liter, 11.5 ± 3.6 mEq f liter, for K+ = 75.4 ± 16.8 mEq/liter, 78.7 ± 10.2 mF.c~Jliter; for total SCFAs = 103.2 ± 9.3 mmol/liter, 75.6 ± 13.8 mmolflitej for acetic acid = 65.5 ± 6.1 mmol j liter, 46.7 ± 10.0 mmoljIiter; for propionic = 27.5 ± 3.4 mmol/liter, 20.1 ± 3.0 mmol/liten for n-butyric = 10.2 ± 1.7 mmol/liter, 8 There was no significant difference in dietary intake between groups 1 and 2 in dietary period 3 (mean ± SEM for group 1 = 26.7 ± 1.6 kcal/kg/day and for group 2 = 27.3 ± 0.9 kcal/kg/day). Stool consistency.…”

Short-Chain Fatty Acids

“…It is well known that animals maintained on a fiber-free diet develop intestinal mucosal atrophy that is most pronounced in the distal small intestine and colon (Ryan et at., 1979;Morin et al, 1980, Ecknauer et at., 1981 and is reversible by the addition of fiber to the diet (Ecknauer et at., 1981;Gordon et at., 1983;Jacobs and Schneeman, 1981;Jacobs and White, 1983;Jacobs and Lupton, 1984). Although most types of fiber exert a strong trophic effect on distal intestinal mucosa, only the most fermentable types of dietary fiber produce any trophic effect on the proximal jejunal mucosa (Vahouny and Cassidy, 1986;Koruda et al, 1987).…”

“…Most enteral feeding formulas contain readily digestible polysaccharides and lack fiber. Fiber-free enteral diets induce atrophy in the colon and distal small bowel (Janne et al, 1977;Ryan et al, 1979;Morin et at., 1980;Ecknauer et at., 1981;Sircar et al, 1983), and total parenteral nutrition (TPN) induces atrophy throughout the intestinal tract (Levine et al, 1974;Johnson et al, 1975;Hughes and Dowling, 1980;Goldstein et al, 1985. As a therapeutic modality, bowel rest, either intravenously (TPN) or enterally (fiber-free elemental diet), is commonly prescribed for patients with disease, injury, or loss of intestine. Although the efficacy of bowel rest cannot be questioned in specific disease entities, one effect of bowel rest is to deprive the intestinal mucosa of its preferred oxidative fuels.…”

Nutrition, operations, and intestinal adaptation

“…In man, gut hormone levels in both fasting and postprandial states are not altered by T P N with the exception of postprandial levels of enteroglucagon and insulin, which are higher after TPN, perhaps secondary to intestinal On their own, elemental diets have been reported either not to affect proximal enteric structure and f u n~t i o n~~, '~ or to produce modest reductions in villus size and cell renewal. 96 By contrast the colon is highly susceptible, becoming lighter and exhibiting depressed levels of DNA synthesis.97~gR Ryan et algR suggested that the colon was 'beyond the reach of luminal nutrition' and reported that the addition of nonabsorbable bulk to an elemental diet increases colonic mucosal DNA synthesis. This bulk was suggested as the factor required for maintenance of a normal colonic muco~a.~* Twelve yrs earlier, however, Dowling and colleaguesg9 showed that dietary bulk as kaolin caused colonic muscle hypertrophy but no detectable mucosal change.…”