Luminal fermentation and colonocyte metabolism in a rat model of enteral nutrition.

Large intestinal fermentation and nutrient metabolism in colonocytes were investigated in a rat model of enteral feeding. Male Wistar rats (240-280 g) were submitted to 7 or 14 days of treatment: intragastric feeding (elemental formula) versus oral feeding (isocaloric and isonitrogenous diet, containing 5% purified cellulose) in the control group. Fermentation products and bacterial populations were analyzed in cecal contents.

Diet, length of gestation, and fecal short chain fatty acids in healthy premature neonates.

Background: Excretion of fecal short-chain fatty acids (SCFAs) may indicate changes in colonic or colonocyte metabolism. The aim of this study was to detect the influence of gestational age and feeding practices on SCFA concentrations and profiles in healthy preterm infants.

Methods: A total of 198 fecal samples (28 infants) were collected from 8 to 21 days of age from 3 groups of preterm infants born at 33 to 37 weeks of gestation and fed either breast milk (group I) or Nutramigen, a lactose-free formula (group II), and extremely preterm infants born before 33 weeks of gestation and fed breast milk (group III).

Differential influence of butyrate concentration on proximal and distal colonic mucosa in rats born germ-free and associated with a strain of Clostridium paraputrificum.

In vivo influence of butyrate in colonic mucosa was studied using a model of gnotobiotic rats monoassociated with a Clostridium paraputrificum. Rats were fed a diet containing increasing amounts of non-digestible carbohydrates, the fermentation of which led to modulated amounts of butyrate in the large intestine. In the proximal colon, the increase in the butyrate concentration alters crypt depth and the number of mucus-containing cells; the increase in butyrate was highly correlated with the number of neutral-mucin-containing cells.

Variations in digestive physiology of rats after short duration flights aboard the US space shuttle.

The purpose of this work was to assess the influence of microgravity on several endogenous and microbial parameters of digestive physiology. On the occasion of two Spacelab Life Sciences missions, SLS-1 (a 9-day space flight) and SLS-2 (a 14-day space flight), Sprague-Dawley rats flown aboard the US space shuttle were compared to age-matched ground-based controls. In both flights, exposure to microgravity modified cecal fermentation: concentration and profile of short-chain fatty acids were altered, whereas urea and ammonia remained unchanged.

Oligofructose contributes to the protective role of bifidobacteria in experimental necrotising enterocolitis in quails.

Bifidobacteria are dominant in the gut of full-term infants, although colonisation by them is often delayed in preterm neonates. Bifidobacteria are recognised to have beneficial effects on digestive disorders and they might prevent neonatal necrotising enterocolitis (NEC), a gastrointestinal disease that predominantly affects premature infants. They have been shown to protect gnotobiotic quails against NEC-like lesions when the birds were inoculated with faecal flora from preterm infants, decreasing the clostridial population.