Four-week short chain fructo-oligosaccharides ingestion leads to increasing fecal bifidobacteria and cholesterol excretion in healthy elderly volunteers

<p>Abstract</p> <p>Background</p> <p>Short-chain fructo-oligosaccharides (scFOS) are increasingly used in human diet for their prebiotic properties. We aimed at investigating the effects of scFOS ingestion on the colonic microflora and oro-fecal transit time in elderly healthy humans.</p> <p>Methods</p> <p>Stools composition, oro-fecal transit time, and clinical tolerance were evaluated in 12 healthy volunteers, aged 69 ± 2 yrs, in three consecutive periods: basal period (2 weeks), scFOS (Actilight^®) ingestion period (8 g/d for 4 weeks) and follow-up period (4 weeks). Two-way ANOVA, with time and treatment as factors, was used to compare the main outcome measures between the three periods.</p> <p>Results</p> <p>Fecal bifidobacteria counts were significantly increased during the scFOS period (9.17 ± 0.17 log cfu/g vs 8.52 ± 0.26 log cfu/g during the basal period) and returned to their initial values at the end of follow-up (8.37 ± 0.21 log cfu/g; P < 0.05). Fecal cholesterol concentration increased during the scFOS period (8.18 ± 2.37 mg/g dry matter vs 2.81 ± 0.94 mg/g dry matter during the basal period) and returned to the baseline value at the end of follow-up (2.87 ± 0.44 mg/g dry matter; P < 0.05). Fecal pH tended to decrease during scFOS ingestion and follow-up periods compared to the basal period (P = 0.06). Fecal bile acids, stool weight, water percentage, and oro-fecal transit time did not change throughout the study. Excess flatus and bloating were significantly more frequent during scFOS ingestion when compared to the basal period (P < 0.05), but the intensity of these symptoms was very mild.</p> <p>Conclusion</p> <p>Four-week 8 g/d scFOS ingestion is well tolerated and leads to a significant increase in fecal bifidobacteria in healthy elderly subjects. Whether the change in cholesterol metabolism found in our study could exert a beneficial action warrants further studies.</p

Effects of ileo-rectal anastomosis on cholesterol metabolism in pigs fed either casein or extruded soya beans

The importance of legume proteins in the cholesterol metabolism has been recognized in different animals, but the contribution of large intestine to this process is still unclear. The present study was undertaken to compare a casein based diet (C) with a diet, where 60% of the protein supplied by casein was replaced by extruded soybean (ES) on cholesterol metabolism of pigs with (I) and without ileo-rectal anastomosis (IRA). Four groups of six growing pigs (28.0 kg) were assigned to the treatments. All the animals presented a moderate hypercholesterolemia and there were no significant differences, due to the protein source or IRA, in LDL- and HDL- cholesterol plasma concentrations. ES significantly depressed (P0.01) total, free and esters of hepatic cholesterol and increased (P<0.01) hepatic total lipids concentration. There were significant (P<0.05) interactions between diet and IRA on HMG CoA reductase and cholesterol 7- hydroxylase activities, but 27–hydroxylase activity was unaffected. Feeding ES showed a tendency (P=0.056) to decrease the activity of LDL liver receptors, depressed free (P0.05), total cholesterol (P0.01) and total bile acid concentration in bile (P0,001), and increased (P0.05) neutral sterols fecal output. There were interactions effects (P0.05) between diet and IRA in the proportion of microbial sterols, bile acid fecal output and proportion of primary and secondary fecal acids. Nevertheless the effects over hepatic cholesterol and neutral sterol output promoted by ES diets, it wasn’t verified any hypocholesterolemic effect, which could be more related with soybean protein structure and LDL receptors modulation