Chicory increases acetate turnover, but not propionate and butyrate peripheral turnovers in rats

• Published in: British journal of nutrition Vol. 99; no. 2; pp. 287 - 296
• Main Authors: Pouteau, Etienne, Rochat, Florence, Jann, Alfred, Meirim, Isabelle, Sanchez-Garcia, Jose-Luis, Ornstein, Kurt, German, Bruce, Ballèvre, Olivier
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.02.2008
• Subjects: Acetates - blood; acetic acid; animal models; Animals; blood chemistry; blood lipids; Butyrates - blood; butyric acid; Carbon Radioisotopes; cecum; Cecum - metabolism; Chicory; Cichorium intybus; colon; Colon - metabolism; experimental design; Fatty Acids, Volatile - biosynthesis; Fatty Acids, Volatile - blood; feed deprivation; Female; Food Deprivation - physiology; Half-Life; inulin; isotope labeling; Kinetics; lipid metabolism; Male; Portal Vein - metabolism; Postprandial Period - physiology; prebiotics; Propionates - blood; propionic acid; Rats; Short-chain fatty acids; tissue weight; Chicory; Rats; Short-chain fatty acids; Kinetics
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114507815790

Chicory roots are rich in inulin that is degraded into SCFA in the caecum and colon. Whole-body SCFA metabolism was investigated in rats during food deprivation and postprandial states. After 22 h of food deprivation, sixteen rats received an IV injection of radioactive 14C-labelled SCFA. The volume of distribution and the fractional clearance rate of SCFA were 0·25–0·27 litres/kg and 5·4–5·9 %/min, respectively. The half-life in the first extracellular rapidly decaying compartment was between 0·9 and 1·4 min. After 22 h of food deprivation, another seventeen rats received a primed continuous IV infusion of 13C-labelled SCFA for 2 h. Isotope enrichment (13C) of SCFA was determined in peripheral arterial blood by MS. Peripheral acetate, propionate and butyrate turnover rates were 29, 4 and 0·3 μmol/kg per min respectively. Following 4 weeks of treatment with chicory root or control diets, eighteen fed rats received a primed continuous IV infusion of 13C-labelled SCFA for 2 h. Intestinal degradation of dietary chicory lowered caecal pH, enhanced caecal and colonic weights, caecal SCFA concentrations and breath H2.The diet with chicory supplementation enhanced peripheral acetate turnover by 25 % (P = 0·017) concomitant with an increase in plasma acetate concentration. There were no changes in propionate or butyrate turnovers. In conclusion, by setting up a multi-tracer approach to simultaneously assess the turnovers of acetate, propionate and butyrate it was demonstrated that a chronic chicory-rich diet significantly increases peripheral acetate turnover but not that of propionate or butyrate in rats.