Effect of polydextrose on intestinal microbes and immune functions in pigs

• Published in: British journal of nutrition 2007-07, Vol.98 (1), p.123-133
• Main Authors: Fava, Francesca, Mäkivuokko, Harri, Siljander-Rasi, Hilkka, Putaala, Heli, Tiihonen, Kirsti, Stowell, Julian, Tuohy, Kieran, Gibson, Glenn, Rautonen, Nina
• Format: Article
• Language: English
• Subjects: animal models; Animals; Biological and medical sciences; Biomarkers - analysis; Cecum - immunology; Cecum - microbiology; Colon - immunology; Colon - microbiology; colorectal neoplasms; Cyclooxygenase 1 - genetics; Cyclooxygenase 2 - genetics; dietary fiber; Dietary Fiber - administration & dosage; Dietary Fiber - analysis; Dietary Supplements; dry matter content; Energy Intake - immunology; experimental diets; Fatty Acids, Volatile - analysis; Feeding. Feeding behavior; Female; fermentation; Food Additives - administration & dosage; Food Additives - analysis; Fundamental and applied biological sciences. Psychology; gene expression; Gene Expression - genetics; Glucans - administration & dosage; Glucans - analysis; high energy diet; human nutrition; immune response; Immune responses; Immunoglobulin A - analysis; immunologic factors; Intestinal bacteria; intestinal microorganisms; intestinal mucosa; Intestinal Mucosa - immunology; Intestine, Small - immunology; Intestine, Small - microbiology; Intestines - immunology; Intestines - microbiology; Male; metabolites; microbial activity; microbial ecology; nutrition research; oligosaccharides; Polydextrose; prostaglandin synthase; short chain fatty acids; Swine; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114507691818

Dietary fibre has been proposed to decrease risk for colon cancer by altering the composition of intestinal microbes or their activity. In the present study, the changes in intestinal microbiota and its activity, and immunological characteristics, such as cyclo-oxygenase (COX)-2 gene expression in mucosa, in pigs fed with a high-energy-density diet, with and without supplementation of a soluble fibre (polydextrose; PDX) (30 g/d) were assessed in different intestinal compartments. PDX was gradually fermented throughout the intestine, and was still present in the distal colon. Irrespective of the diet throughout the intestine, of the four microbial groups determined by fluorescent in situ hybridisation, lactobacilli were found to be dominating, followed by clostridia and Bacteroides. Bifidobacteria represented a minority of the total intestinal microbiota. The numbers of bacteria increased approximately ten-fold from the distal small intestine to the distal colon. Concomitantly, also concentrations of SCFA and biogenic amines increased in the large intestine. In contrast, concentrations of luminal IgA decreased distally but the expression of mucosal COX-2 had a tendency to increase in the mucosa towards the distal colon. Addition of PDX to the diet significantly changed the fermentation endproducts, especially in the distal colon, whereas effects on bacterial composition were rather minor. There was a reduction in concentrations of SCFA and tryptamine, and an increase in concentrations of spermidine in the colon upon PDX supplementation. Furthermore, PDX tended to decrease the expression of mucosal COX-2, therefore possibly reducing the risk of developing colon cancer-promoting conditions in the distal intestine.