Dietary inulin intake and age can significantly affect intestinal absorption of calcium and magnesium in rats: a stable isotope approach

BACKGROUND: previous studies have shown that non-digestible inulin-type fructan intake can increase intestinal mineral absorption in both humans and animals. However, this stimulatory effect on intestinal absorption may depend on experimental conditions such as duration of fermentable fiber intake, mineral diet levels and animals' physiological status, in particular their age. OBJECTIVES: the aim of this study was to determine the effect of inulin intake on Ca and Mg absorption in rats at different age stages. METHODS: eighty male Wistar rats of four different ages (2, 5, 10 and 20 months) were randomized into either a control group or a group receiving 3.75% inulin in their diet for 4 days and then 7.5% inulin for three weeks. The animals were fed fresh food and water ad libitum for the duration of the experiment. Intestinal absorption of Ca and Mg was determined by fecal monitoring using stable isotopic tracers. Ca and Mg status was also assessed. RESULTS: absorption of Ca and Mg was significantly lower in the aged rats (10 and 20 mo) than in the young and adult rat groups. As expected, inulin intake increased Ca and Mg absorption in all four rat groups. However, inulin had a numerically greater effect on Ca absorption in aged rats than in younger rats whereas its effect on Mg absorption remained similar across all four rat age groups. CONCLUSION: the extent of the stimulatory effect of inulin on absorption of Ca may differ according to animal ages. Further studies are required to explore this effect over longer inulin intake periods, and to confirm these results in humans

Contribution à l'étude du stress oxydant dans un modèle de syndrome métabolique (le rat recevant un régime riche en fructose)

CLERMONT FD-BCIU-Santé (631132104) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Profil lipoproteique de la vache laitiere.

National audienc

Evolution des lipides et lipoproteines plasmatiques chez la vache en debut de lactation

National audienc

Dietary inulin in mice stimulates Mg2+ absorption and modulates TRPM6 and TRPM7 expression in large intestine and kidney

International audienceComplex fermentable carbohydrates, such as inulin-type fructans have been shown to improve Mg2+ absorption in the hindgut and body stores. The mechanisms for this are not well understood. The newly identified transient receptor potential melastatin 6 and 7 (TRPM6 and TRPM7) channels have been shown to function in active epithelial Mg2+ transport in the apical membrane of epithelial cells, the kidney and intestine and to be regulated by dietary intake. To determine the modulation of TRPM6 and TRPM7 expression in kidney and large intestine by long-chain inulin ingestion, C57B16J mice were fed a control or a long-chain inulin enriched diet (65 g of inulin/kg diet) for two weeks. Our results show that the inulin-enriched diet ameliorated Mg2+ absorption and Mg2+ bone stores. These features were accompanied by increased TRPM6 and TRPM7 expression in the hindgut. Downregulation of TRPM6 in the kidney of inulin fed mice could be related to reduced Mg2+ reabsorption and supports the beneficial effect of dietary fibers on Mg2+ absorption and stores. Inulin ingestion also modulates TRPM6 and TRPM7 expression in the large intestine. The origin and role of this modulation is not known. Changes in Mg2+ fluxes, lower pH of the digestive content and increased cell proliferation may be involved

Métabolisme des lipoprotéines chez la vache laitière lors de stéatose hépatique

50 ref.International audienc

Recent experimental and clinical data on magnesium and sport.

National audienc

Composition lipidique du foie chez la vache laitiere en debut de lactation en relation avec la steatose hepatique.

International audienc

Recent experimental and clinical data on magnesium and sport.

International audienc

Plasma lipoproteins in dairy cows with naturally occurring severe fatty liver : evidence of alteration in the distribution of apo AI-containing lipoproteins.

International audienc