The effects of increased colonic fermentation of dietary fibres (DF) on net portal flux (NPF) of carbohydrate-derived metabolites (glucose, SCFA and especially butyrate), hormones (insulin, C-peptide, GLP-1, GIP) and NEFA were studied in a healthy catheterised pig model. Six 59 ± 3.8 kg pigs were fitted with catheters in the mesenteric artery, the portal and hepatic vein, and a flowprobe around the portal vein and included in a double 3x3 crossover design with three daily feedings (at 9.00, 14.00 and 19.00 hours). Fasting and 5 hours postprandial blood samples were collected after 7 days adaptation to each diet. The pigs were fed a low DF western style control diet (WSD) and two high DF diets; an arabinoxylan (AXD) and a resistant starch (RSD) enriched diet. The NPF of insulin was lower (P = 0.04) in AXD fed pigs (4.6 nmol/h) compared to RSD fed pigs (10.5 nmol/h), despite the lowest NPF of glucose was observed in RSD fed pigs (203 mmol/h, P = 0.02). The NPF of total SCFA, acetate, propionate, and butyrate were high, intermediate, and low (P < 0.01) in AXD, RSD, and WSD fed pigs, respectively, with the largest relative increase for butyrate in response to arabinoxylan supplementation. In conclusion, RSD and AXD had different effects on net portal insulin and glucose flux, suggesting different impact of arabinoxylan and resistant starch on human health.
British Journal of Nutrition, 2014, Vol 111, Issue 9, p. 1564-76